JP6259586B2 - Adhesive sheet for glass protection - Google Patents

Description

  The present invention relates to an adhesive sheet for protecting glass. In detail, it is related with the adhesive sheet for glass protection for affixing on the outer surface of the window glass for motor vehicles, and protecting this window glass.

  In order to protect an exterior coating film from damage, adhesion of dust, and the like during storage and distribution of automobiles, a technique for protecting the coating film by attaching a coating film protection sheet to the coating film is known. The coating film protective sheet used for this purpose generally has a non-porous plastic film (base material) and a pressure-sensitive adhesive layer provided on one side of the non-porous plastic film. It is configured to be able to achieve the protection purpose by being adhered to the surface.

  The window glass of the automobile is exposed to the outside of the automobile like the coating film, and may be damaged during storage and distribution. For example, a part of the window glass may be scratched or cracked when a pebble on the road jumps and hits the window glass during transportation of the automobile (stepping stone). When a window glass of an automobile is damaged or cracked, a large burden may be generated in terms of work and cost, such as requiring replacement of the entire window glass. For this reason, in recent years, a protective material for protecting the window glass of the automobile during the storage and distribution process of the automobile has been demanded. Patent documents 1-3 are mentioned as technical literature about an adhesive sheet for affixing on the outer surface of the window glass of a car, and protecting this window glass.

JP 2007-84795 A JP 2007-246589 A JP 2010-121044 A

  However, in spite of such demand, the use of the pressure-sensitive adhesive sheet for protecting the glass in the storage and distribution process of automobiles has not yet spread. One reason for this is that automobile windshields and rear window glasses generally have a complicated three-dimensional shape, so that the adhesive sheet is properly aligned with the shape of its outer surface (typically a convex curved surface). It may be difficult to attach or it may take time and effort to appropriately apply. If the pressure-sensitive adhesive sheet for glass protection is not properly applied, the pressure-sensitive adhesive sheet will be blown by the wind while it is being stored or transported, and the original protective purpose will not be achieved. Intrusion of rainwater may cause inconveniences such as a mark on the window glass and a reduction in commercial value.

  In general, if the flexibility of the pressure-sensitive adhesive sheet is increased, the curved surface followability of the pressure-sensitive adhesive sheet is improved, and it becomes easy to deform along the surface shape of the adherend. However, since a highly flexible pressure-sensitive adhesive sheet has low shape stability before being attached to an adherend, its handling tends to be difficult. In particular, in a pressure-sensitive adhesive sheet having a relatively large area, which is used for protecting automobile window glass, when the pressure-sensitive adhesive sheet is highly flexible, the work load during carrying and pasting is likely to increase. When the work load increases, it becomes difficult to properly attach the adhesive sheet to the window glass, so the work time becomes longer. If the working time is forcibly shortened, the desired protective performance cannot be achieved due to the deterioration of the pasting quality, such as the possibility of generating large wrinkles.

  In addition, since a flexible adhesive sheet having a high curved surface followability generally has a large expansion and contraction due to a temperature change, it tends to be lifted from the surface of the adherend due to a temperature change after application. The floating of the pressure-sensitive adhesive sheet from the adherend can cause problems such as peeling off of the pressure-sensitive adhesive sheet and intrusion of rainwater. The adhesive sheet for protecting glass attached to the window glass of an automobile can be exposed to a wide range of temperature changes when the automobile is stored outdoors for a long period of time. is important.

  The present invention has been made in view of such circumstances, and the main purpose thereof is a glass that is easily attached along the outer surface of a window glass of an automobile and that is less likely to float due to a temperature change after application. It is to provide a protective adhesive sheet.

According to this specification, the adhesive sheet for glass protection for affixing on the outer surface of the window glass for motor vehicles and protecting this window glass is provided. The pressure-sensitive adhesive sheet for glass protection includes a plastic film as a base material and a pressure-sensitive adhesive layer provided on one surface of the base material. The glass protective pressure-sensitive adhesive sheet satisfies the following conditions (A) to (C).
(A) The haze value is 10% or less.
(B) The heating change rate (HE (60-10)) between 60 ° C. and 10 ° C. is 2.0% or less.
(C) The stress at 5% elongation at 23 ° C. is 7 to 30 N / 20 mm.

  Since the pressure-sensitive adhesive sheet for glass protection that satisfies both the above conditions (B) and (C) has a good balance between curved surface followability and handleability, it is easy to apply appropriately along the outer surface of the window glass, and after application It is possible to effectively suppress the occurrence of wrinkles and wrinkles. As a result, it is possible to continuously exhibit good protection performance by preventing peeling and intrusion of rainwater. Moreover, by satisfying the condition (A), a good field of view can be ensured in the window glass to which the pressure-sensitive adhesive sheet is attached. Therefore, the said adhesive sheet can respond suitably also to the situation which drives and moves the motor vehicle in the state in which this adhesive sheet was affixed on the window glass.

The glass protective adhesive sheet preferably has a tensile modulus at 23 ° C. in the range of 400 to 1800 N / mm ² . By setting the tensile modulus to be in the above range, a glass protective pressure-sensitive adhesive sheet that simultaneously satisfies the above conditions (B) and (C) can be easily obtained.

  As for the adhesive sheet for glass protection disclosed here, it is preferable that the thickness of an adhesive layer is 10 micrometers or less. The glass protective pressure-sensitive adhesive sheet having such a structure is easy to push out water between the pressure-sensitive adhesive layer and the adherend to the outside of the pressure-sensitive adhesive sheet sticking range. Therefore, as will be described later, it can be preferably pasted by a pasting method using pasting water.

  In a preferred embodiment of the glass protective pressure-sensitive adhesive sheet disclosed herein, the glass protective pressure-sensitive adhesive sheet constitutes a pressure-sensitive adhesive sheet with a release liner. The pressure-sensitive adhesive sheet with a release liner includes the above-mentioned pressure-sensitive adhesive sheet for glass protection and a release liner that is detachably laminated on the adherend-adhered surface of the pressure-sensitive adhesive layer. A glass protective pressure-sensitive adhesive sheet having such a form (a glass protective pressure-sensitive adhesive sheet with a release liner) is preferable because an operation of cutting (for example, punching out) the original pressure-sensitive adhesive sheet into a desired outer shape can be performed efficiently. Moreover, it is preferable also from a viewpoint that the adhesive sheet for glass protection prepared by the desired external shape can be stored compactly until use.

  In another preferred embodiment of the pressure-sensitive adhesive sheet for glass protection disclosed herein, the pressure-sensitive adhesive sheet for glass protection constitutes a pressure-sensitive adhesive sheet with an auxiliary sheet. The pressure-sensitive adhesive sheet with an auxiliary sheet comprises a glass protective pressure-sensitive adhesive sheet and an auxiliary sheet (application sheet) laminated on the other surface of the substrate, that is, the surface opposite to the surface on which the pressure-sensitive adhesive layer is provided (back surface). ). The auxiliary sheet includes an auxiliary base material and an auxiliary pressure-sensitive adhesive layer provided on one surface thereof. The auxiliary pressure-sensitive adhesive layer is detachably attached to the other surface (back surface) of the base material constituting the glass protective pressure-sensitive adhesive sheet. The glass protective pressure-sensitive adhesive sheet (pressure-sensitive adhesive sheet with an auxiliary sheet) having such a form has good handleability since the shape stability of the glass protective pressure-sensitive adhesive sheet is enhanced by the auxiliary sheet. Further, since the auxiliary sheet is detachably attached to the back surface of the glass protective pressure-sensitive adhesive sheet (that is, the back surface of the substrate), the glass protective pressure-sensitive adhesive sheet is attached in the form of the pressure-sensitive adhesive sheet with the auxiliary sheet ( After being attached to the window glass, the auxiliary sheet can be peeled leaving the glass protective adhesive sheet on the adherend surface. The remaining glass protective pressure-sensitive adhesive sheet can exhibit good curved surface followability and anti-floating property with respect to the adherend surface. Therefore, the handleability of the pressure-sensitive adhesive sheet for protecting glass, the curved surface followability and the anti-floating property can be made highly compatible.

  In a preferred embodiment of the glass protective pressure-sensitive adhesive sheet disclosed herein, the glass protective pressure-sensitive adhesive sheet is processed into an outer shape that fits inside the outer edge of the outer surface of the automotive window glass (for example, punching). Has been. The pressure-sensitive adhesive sheet for protecting a glass processed into such a shape can be efficiently attached to the outer surface on the inner side from the outer edge of the window glass without taking the trouble of removing the portion protruding from the outer edge of the window glass. it can.

  The pressure-sensitive adhesive sheet for protecting a glass processed into the outer shape may be a center sheet that covers a central portion of the window glass for an automobile. By covering the center portion of the window glass with such a center sheet, the pasting range including the center portion can be suitably protected from damage due to stepping stones or the like. Although not particularly limited, the area of the center sheet can be, for example, 50% to 95% of the area of the outer surface of the window glass.

In a preferred embodiment, a protruding portion is provided on one side of the glass protective pressure-sensitive adhesive sheet so that the outline of the glass protective pressure-sensitive adhesive sheet partially protrudes outward. Such a protrusion is easily attached along the curvature of the window glass. Generally, the peripheral part of the window glass for automobiles is often strongly curved as compared with the center part of the window glass. The protrusion part of the said adhesive sheet for glass protection can be appropriately affixed also to such a peripheral part. In the case where the glass protective pressure-sensitive adhesive sheet is a center sheet that covers the central part of the window glass for automobiles, it is particularly meaningful that the protrusions are provided.
It is preferable that two or more of the protruding portions are provided on one side of the glass protective pressure-sensitive adhesive sheet at intervals. In the glass protective pressure-sensitive adhesive sheet having such a shape, the contour line of the glass protective pressure-sensitive adhesive sheet is recessed inward of the pressure-sensitive adhesive sheet between two adjacent protrusions of the two or more protrusions. Is formed. By utilizing this valley portion, it is possible to escape (absorb) distortion that may occur because the pressure-sensitive adhesive sheet for protecting glass follows the surface shape of the window glass. Thereby, generation | occurrence | production of a wrinkle can be suppressed and it can become easy to affix the said adhesive sheet for glass protection appropriately. Although it does not specifically limit, the depth of the said trough part can be 20 mm or more and 200 mm or less, for example.

  According to this specification, the adhesive sheet set for glass protection for affixing on the outer surface of the window glass for motor vehicles, and protecting this window glass is also provided. The said adhesive sheet set for glass protection contains the said center sheet | seat and the edge sheet | seat processed into the external shape which can be affixed on the peripheral part along the outer end of the at least one side of the said window glass for motor vehicles. The adhesive sheet set for protecting glass having such a configuration can appropriately and efficiently affix the center sheet and the edge sheet included in the set to the outer surface of the window glass for automobiles. In addition, the center sheet and the edge sheet can be prevented from floating or peeling off, and good protection performance can be exhibited.

It is typical sectional drawing which shows the example of 1 structure of the adhesive sheet for glass protection. It is typical sectional drawing which shows one structural example of the adhesive sheet for glass protection with an auxiliary sheet. It is typical sectional drawing which shows one structural example of the adhesive sheet for glass protection with a release liner. It is a typical top view which shows the principal part of the motor vehicle by which the adhesive sheet for glass protection of 1st Embodiment was affixed on the front window glass. It is a typical top view explaining the sticking method of the adhesive sheet for glass protection of 1st Embodiment. It is a typical top view explaining the sticking method of the adhesive sheet for glass protection of 1st Embodiment. It is typical sectional drawing in the VII-VII line of FIG. It is a typical top view which shows the positional relationship of the adhesive sheet for glass protection of 1st Embodiment, and the braid | blade member in the nearest position WR1. It is a typical top view which shows the front window glass on which the adhesive sheet for glass protection of 2nd Embodiment was affixed. It is a typical top view which shows the rear window glass on which the adhesive sheet for glass protection of 3rd Embodiment was affixed.

Hereinafter, preferred embodiments of the present invention will be described. Note that matters other than matters specifically mentioned in the present specification and necessary for the implementation of the present invention can be grasped as design matters of those skilled in the art based on the prior art in this field. The present invention can be carried out based on the contents disclosed in this specification and common technical knowledge in the field.
In addition, in the following drawings, the same code | symbol is attached | subjected and demonstrated to the member and site | part which have the same effect | action, and the overlapping description may be abbreviate | omitted or simplified. In addition, the embodiment described in the drawings is modeled as necessary to clearly explain the present invention, and is not necessarily an accurate representation of the size and scale of the glass protective adhesive sheet that is actually used. is not.

  The glass protective pressure-sensitive adhesive sheet disclosed herein is used by being attached to an automobile window glass. The window glass for automobiles herein may be in a state assembled to the body of the automobile, or may be in a state before being assembled. That is, the pressure-sensitive adhesive sheet for protecting glass disclosed herein may be affixed to a finished product or a window glass assembled in an automobile in production, or may be affixed to an automobile window glass before being assembled in an automobile. .

  The pressure-sensitive adhesive sheet for protecting glass disclosed herein is applied to various window glasses (for example, front window glass) provided in an automobile, and is used in a mode in which a part or all of the outer surface is protected. Can be done. The range (region) of the window glass for automobiles protected by the glass protective adhesive sheet is not particularly limited. For example, the above-mentioned pressure-sensitive adhesive sheet for protecting a glass may be used in such a manner that one sheet covers almost the entire range of the outer surface of an automotive window glass (typically, more than 95% of the area of the outer surface). You may use as a center sheet | seat which covers the area | region containing a center part among window glass, and may be used as an edge sheet | seat which covers the area | region containing at least one part of a peripheral part among the said window glasses. In addition, the number of the glass protective adhesive sheets used for protecting one window glass is not particularly limited, and may be one sheet or a plurality of sheets (for example, 2 to 5 sheets).

  In the present specification, the central portion of the window glass for an automobile refers to the length of the center line in the width direction and the height from the intersection of the center line in the width direction of the window glass and the center line in the height direction. A region inside a circle having a diameter corresponding to 30% of the shorter length of the direction center line. Here, the width direction and the height direction of the window glass refer to directions based on the attitude (orientation) of the window glass in a state where the window glass is assembled in an automobile. Further, the length of the center line in the width direction of the window glass refers to the length of a line segment obtained by dividing the center line in the width direction at the outer end of the window glass. Similarly, the length of the center line in the height direction of the window glass refers to the length of a line segment obtained by dividing the center line in the height direction at the outer end of the window glass. Further, in the following, when the window glass is assembled to an automobile, the upper side (roof side) side is referred to as the upper side, and the lower side (ground side) side is referred to as the lower side, and the right side when viewed from the outer surface side of the window glass. The side may be called the right side and the left side may be called the left side.

  In this specification, the peripheral part of the window glass for automobiles is a frame-like (annular) region along the outer edge of the window glass for automobiles, and the width of the frame in the frame shape is the width direction of the window glass. A region having a width corresponding to 10% of the shorter one of the length of the center line and the length of the center line in the height direction.

  In this specification, the outer edge of the window glass for an automobile is a region where the outer surface of the window glass is exposed to the outside in a state where the window glass is attached to the automobile and a protective sheet is not attached. The end in the surface direction. Therefore, for example, in a window glass attached to an automobile with a window molding attached to the outer periphery, the boundary line between the area sandwiched between the window molding and the area exposed from the window molding on the outer surface of the window glass is the window glass. It becomes the outer end.

  Moreover, in this specification, the area of the outer surface of the window glass for automobiles refers to the area where the outer surface is exposed when the window glass is attached to the automobile and the protective sheet is not attached. . That is, it refers to the area of the inner region surrounded by the outer edge of the outer surface of the window glass. Hereinafter, the area of the outer surface of the window glass may be simply referred to as “the area of the window glass”.

  In the present specification, appropriately attaching an adhesive sheet to a window glass for an automobile means realizing a state of application suitable for exhibiting the protective performance of the window glass. For example, reducing the number and extent (length, etc.) of wrinkles that may occur when the pressure-sensitive adhesive sheet is applied is effective for realizing the application state.

  As shown in FIG. 1, for example, as shown in FIG. 1, the glass protective pressure-sensitive adhesive sheet disclosed herein is provided on a plastic film (hereinafter also referred to as a film substrate) as a substrate 62 and one surface of the substrate 62. Adhesive layer 64. Here, the plastic film typically refers to a non-porous plastic film and is a concept distinguished from a woven fabric and a non-woven fabric. This pressure-sensitive adhesive sheet for glass protection is characterized by satisfying the above conditions (A) to (C). Hereinafter, each condition will be described in more detail.

The adhesive sheet for glass protection disclosed here has a haze value of 10% or less (condition (A)). The haze value (%) of the pressure-sensitive adhesive sheet for glass protection is measured by the method described in Examples described later.
The pressure-sensitive adhesive sheet for glass protection that satisfies the above haze value is excellent in transparency. Therefore, according to the adhesive sheet for protecting a glass, it is possible to secure a field of view that can appropriately cope with a situation of driving and moving an automobile with the adhesive sheet attached to the window glass. From the viewpoint of obtaining a better field of view, the haze value of the glass protective pressure-sensitive adhesive sheet is preferably 7% or less, more preferably 5% or less, and even more preferably 3% or less. The haze value can be adjusted by selecting the composition, thickness, surface state, and the like of the base material and the pressure-sensitive adhesive layer that constitute the glass protective pressure-sensitive adhesive sheet.
In addition, the color in particular of the adhesive sheet for glass protection is not restrict | limited. For example, a colored and transparent sheet satisfying a haze value of 10% or less or a colorless and transparent sheet may be used.

Here, the “haze value” refers to a ratio of diffuse transmitted light to total transmitted light when the target film or sheet is irradiated with visible light. Also called cloudy price. The haze value can be expressed by the following formula. Here, Th is the haze value (%), Td is the scattered light transmittance, and Tt is the total light transmittance.
Th (%) = Td / Tt × 100

The pressure-sensitive adhesive sheet for glass protection disclosed herein has a heating change rate (HE (60-10)) between 60 ° C. and 10 ° C. of 2.0% or less (condition (B)). The heating change rate (HE (60-10)) of the pressure-sensitive adhesive sheet for glass protection is a method described in Examples described later, using a measurement sample in which the flow direction (MD) of the pressure-sensitive adhesive sheet for glass protection is the vertical direction. Measured by Here, the flow direction (MD) of the pressure-sensitive adhesive sheet for glass protection refers to the direction corresponding to the MD of the base material (film base material) constituting the pressure-sensitive adhesive sheet for glass protection.
A glass protective adhesive sheet with a small rate of change in heating (HE (60-10)) has little expansion and contraction due to temperature change. For example, an automobile to which a glass protective adhesive sheet is attached is stored outdoors for a long period of time. Even if exposed to a wide range of temperature changes, it is possible to suppress the occurrence of floats and wrinkles and maintain a good pasting state. From this viewpoint, the heating change rate (HE (60-10)) of the pressure-sensitive adhesive sheet for glass protection is more preferably 1.7% or less, and 1.5% or less (for example, 1.3% or less). More preferably. Although the lower limit of the heating change rate (HE (60-10)) is not particularly limited, from the viewpoint of facilitating coexistence with the condition (C), the heating change rate (HE (60-10)) is usually 0.5. % Is more preferable, and 0.7% or more is more preferable. The rate of change in heating (HE (60-10)) can be adjusted by selecting the composition, thickness, etc. of the substrate constituting the glass protective adhesive sheet.

When it is difficult to determine the MD of the pressure-sensitive adhesive sheet for glass protection, the direction (MD ′) specified by the following method can be used as the MD in each measurement or test disclosed herein for convenience.
That is, after the glass protective pressure-sensitive adhesive sheet is left in an environment of 23 ° C. and 50% RH for 1 hour or longer, an arbitrary direction of the pressure-sensitive adhesive sheet is defined as a first direction, and a direction orthogonal to the first direction is a second direction. As above, a square-shaped measurement sample having a length of 200 mm and a width of 200 mm with the first direction as the vertical direction and the second direction as the horizontal direction is cut out. A pair of marked lines is put in the measurement sample with an interval of about 150 mm in the first direction, and a pair of marked lines is put in the second direction with an interval of about 150 mm. The operation of putting these marked lines is completed within 5 minutes after cutting out the measurement sample.
Further, from the glass protective pressure-sensitive adhesive sheet after being left in the environment of 23 ° C. and 50% RH for 1 hour or more, a third direction and a second direction that are at an angle of 45 degrees with the first direction and the second direction are perpendicular to each other. A square measurement sample having a length of 200 mm and a width of 200 mm with the four directions as the vertical direction and the horizontal direction, respectively, is cut out. A pair of marked lines is put on the measurement sample with an interval of about 150 mm in the third direction, and a pair of marked lines is put with an interval of about 150 mm in the fourth direction. The operation of putting these marked lines is completed within 5 minutes after cutting out the measurement sample.
After holding the measurement sample with the marked line in the drying oven at 80 ° C. for 1 hour, the length between each marked line is measured to the first decimal place with calipers in an environment at 80 ° C. To do. Next, after holding the measurement sample in a 23 ° C. environment for 1 hour, the length between each marked line is measured to the first decimal place with a caliper in the 23 ° C. environment.
The length between each marked line measured in an environment of 80 ° C. is L _80, and the length between each marked line measured in an environment of 23 ° C. is L ₂₃ . For each of the two directions, the third direction, and the fourth direction, the rate of change in heating (HE (80-23)) between 80 ° C. and 23 ° C. is calculated by the following formula, and the direction with the largest value is the MD. 'And.
Rate of change in heating (HE (80-23)) (%) = | (L ₈₀ -L ₂₃ ) / L ₈₀ | × 100

  A value obtained by measurement of the rate of change in heating (HE (60-10)) performed between 60 ° C. and 10 ° C., as will be described later, using a measurement sample having the MD ′ thus specified in the vertical direction. Can be employed as an approximate value of the rate of change in heating (HE (60-10)) for the measurement sample with MD in the vertical direction. A glass protective pressure-sensitive adhesive sheet having an approximate value of 2.0% or less (more preferably 1.7% or less, still more preferably 1.5% or less, for example 1.3% or less) is preferable. Moreover, the adhesive sheet for glass protection whose said approximate value is more than 0.5% (more preferably 0.7% or more) is preferable.

The adhesive sheet for protecting glass disclosed herein has a stress at 5% elongation at 23 ° C. (hereinafter, the stress at 5% elongation in this specification may be expressed as “ 5% modulus ” ) of 7 to 7%. It is in the range of 30 N / 20 mm (condition (C)). The 5% modulus of the pressure-sensitive adhesive sheet for glass protection is measured by a method described in Examples described later, using a measurement sample whose length direction is the flow direction (MD) of the pressure-sensitive adhesive sheet for glass protection.
The glass protective adhesive sheet having a 5% modulus in the above range has a good balance between curved surface followability and handleability, and is easily attached appropriately along the surface shape of the window glass. From this viewpoint, the 5% modulus of the pressure-sensitive adhesive sheet for glass protection is preferably in the range of 7 to 25 N / 20 mm, and more preferably in the range of 8 to 20 N / 20 mm (for example, 9 to 15 N / 20 mm). The 5% modulus can be adjusted by selecting the composition and thickness of the base material constituting the glass protective pressure-sensitive adhesive sheet.
When it is difficult to determine the MD of the glass protective pressure-sensitive adhesive sheet, a 5% modulus measurement is performed by the method described later using a measurement sample having the MD ′ specified by the above method in the length direction. Can be used as an approximate value of 5% modulus for MD of the pressure-sensitive adhesive sheet for glass protection. A glass protective pressure-sensitive adhesive sheet satisfying the preferable value of 5% modulus described above is preferable. The same applies to the tensile modulus and other characteristics described later.

  The glass protective adhesive sheet that satisfies both the above heating rate of change (HE (60-10)) and 5% modulus has a good balance between curved surface followability and handleability. It is easy to affix and can effectively suppress the occurrence of floats and wrinkles after affixing. Therefore, it can be efficiently affixed to the window glass for automobiles and can exhibit high protection performance.

It is preferable that the adhesive sheet for glass protection disclosed here has a tensile elastic modulus at 23 ° C. (hereinafter sometimes simply referred to as tensile elastic modulus) in the range of 400 to 1800 N / mm ² . In addition, the tensile elasticity modulus of the adhesive layer which comprises the adhesive sheet for glass protection disclosed here is very small compared with the tensile elasticity modulus of the base material which comprises this adhesive sheet. For this reason, the value converted into the value per cross-sectional area of a base material shall be used as a tensile elasticity modulus here. Specifically, the tensile elastic modulus can be obtained by a method described in the examples described later, using a measurement sample whose length direction is the flow direction (MD) of the pressure-sensitive adhesive sheet for glass protection.

When the tensile elastic modulus is low, the glass protective adhesive sheet tends to be deformed along the curved surface (curved surface followability is improved). By this, it can become easy to attach the adhesive sheet for glass protection appropriately along the surface shape of a window glass. From this viewpoint, the tensile modulus is more preferably 1500 N / mm ² or less, and more preferably 1300 N / mm ² or less. Although the lower limit of the tensile modulus is not particularly limited, 400 N / mm ² or more is usually appropriate from the viewpoint of facilitating coexistence with the preferable heating change rate (HE (60-10)) described above, and 500 N / mm. ² or more is preferable, and 600 N / mm ² or more is more preferable. When the tensile elastic modulus is high, it tends to be easy to prevent the occurrence of floating and wrinkling after pasting. A tensile elasticity modulus can be adjusted with the composition of the base material which comprises the adhesive sheet for glass protection, for example.

The composition and structure of the film substrate used for the glass protective pressure-sensitive adhesive sheet disclosed herein are not particularly limited, and are selected so that a glass protective pressure-sensitive adhesive sheet satisfying the above conditions (A) to (C) is realized. be able to. For example, the structure of the film substrate may be a single layer structure or a multilayer structure of two layers or three or more layers. From the viewpoint of transparency and the like, a plastic film having a single layer structure can be preferably adopted as the film base material.
The resin material constituting the film substrate can be, for example, a polyolefin resin, a polyester resin such as polyethylene terephthalate (PET), a polyamide resin, a polycarbonate resin, a polyurethane resin, an acrylic resin, or the like. These can be used alone or in combination of two or more. When two or more kinds of resins are used in combination, these resins may be used in a blend, or may be used separately (for example, as materials constituting different layers in a plastic film having a multilayer structure).

  From the viewpoint of easily realizing a glass protective pressure-sensitive adhesive sheet satisfying the above-mentioned haze value, rate of change in heating (HE (60-10)) and 5% modulus, a film substrate whose main component of the resin material is a polyolefin resin is provided. It can be preferably used. Such a film substrate is also preferable from the viewpoint of the weather resistance of the pressure-sensitive adhesive sheet for protecting glass. Here, that the main component of the resin material is a polyolefin resin means that more than 50% by mass of the resin material is a polyolefin resin. 70 mass% or more is preferable, as for the ratio of polyolefin resin among the said resin materials, 90 mass% or more is more preferable, and 95 mass% or more is further more preferable. In a preferred embodiment, the resin material substantially consists of a polyolefin resin.

  Preferable examples of the polyolefin resin include polyethylene resin (PE) and polypropylene resin (PP). A film substrate containing one or both of PE and PP as the resin material is preferred. In a preferred embodiment, 75% by mass or more of the resin material contained in the film substrate is PP. PP may be substantially 100% by mass of the resin material contained in the film substrate. When the resin material includes other resin in addition to PP, the other resin may be a polyolefin other than PP, for example, PE.

The PP can be various polymers (propylene-based polymers) containing propylene as a component. The concept of the propylene-based polymer here includes, for example, the following.
Propylene homopolymer (homopolypropylene). For example, isotactic polypropylene, syndiotactic polypropylene, atactic polypropylene.
Random copolymers of propylene and other α-olefins (random polypropylene). Typically, a random copolymer of propylene and one or more selected from ethylene and an α-olefin having 4 to 10 carbon atoms. Preferably, a random copolymer containing propylene as a main monomer (main constituent monomer, that is, a component occupying 50% by mass or more of the whole monomer; the same shall apply hereinafter). For example, a random copolymer of 96 to 99.9 mol% of propylene and 0.1 to 4 mol% of another α-olefin (preferably ethylene and / or butene).
A copolymer obtained by block copolymerization of propylene with other α-olefin (block polypropylene). Typically, a copolymer obtained by block copolymerizing propylene with one or more selected from ethylene and an α-olefin having 4 to 10 carbon atoms. Block polypropylene containing propylene as a main monomer is preferable, and typically further includes a rubber component containing at least one of propylene and the above-mentioned other α-olefins as a by-product. For example, a polymer obtained by block copolymerization of 90 to 99.9 mol% of propylene with 0.1 to 10 mol% of other α-olefin (preferably ethylene and / or butene) and propylene and other α- A block polypropylene further comprising a rubber component containing at least one of olefins as a component.
Reactor blend type thermoplastic olefin resin (TPO) or thermoplastic elastomer (TPE) obtained by copolymerizing a large amount of rubber components with the propylene-based polymer as described above. Alternatively, dry blend type TPO or TPE obtained by mechanically dispersing the rubber component.
A copolymer of a monomer having another functional group in addition to a polymerizable functional group (functional group-containing monomer) and propylene, and a copolymer obtained by copolymerizing such a functional group-containing monomer with a propylene-based polymer.

  The resin material which comprises a film base material may contain 1 type, or 2 or more types of such PP. When two or more types of PP are included, these PPs may be used in a blend or may be used separately. There is no restriction | limiting in particular in the usage-amount ratio (blend ratio) of those PP.

  The PE may be various polymers (ethylene-based polymer) containing ethylene as a component. The ethylene polymer may be a homopolymer of ethylene or may be a copolymer obtained by copolymerizing ethylene as the main monomer with another α-olefin. Preferred examples of the other α-olefins include 3 carbon atoms such as propylene, 1-butene (may be branched 1-butene), 1-hexene, 4-methyl-1-pentene, 1-octene and the like. To 10 alpha-olefins. Further, it may be a copolymer of a monomer having another functional group in addition to the polymerizable functional group (functional group-containing monomer) and ethylene, or a copolymer obtained by copolymerizing such a functional group-containing monomer with an ethylene polymer. . Examples of the copolymer of ethylene and a functional group-containing monomer include, for example, ethylene-vinyl acetate copolymer (EVA), ethylene-acrylic acid copolymer (EAA), ethylene-methacrylic acid copolymer (EMAA), and ethylene-acrylic. Methyl acid copolymer (EMA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl methacrylate copolymer (EMMA), ethylene and (meth) acrylic acid (ie, acrylic acid and / or methacrylic acid) ) And the like are cross-linked with metal ions. Examples of the PE include high density polyethylene (HDPE), medium density polyethylene (MDPE), low density polyethylene (LDPE), and linear low density polyethylene (LLDPE).

  The resin material which comprises a film base material may contain 1 type, or 2 or more types of such PE. When two or more types of PE are included, these PEs may be used by blending or may be used separately. There is no restriction | limiting in particular in the usage-amount ratio (blend ratio) of those PE.

  Preferable examples of the resin material constituting the film substrate include random polypropylene containing propylene as a main monomer and ethylene as a copolymerization component. You may use combining this random polypropylene and other resin (for example, PE). By using such random polypropylene, a pressure-sensitive adhesive sheet for glass protection that satisfies the above-mentioned preferable haze value, rate of change in heating (HE (60-10)) and 5% modulus can be suitably realized. As the film substrate in the technology disclosed herein, a plastic film having a single layer structure made of a resin material in which the content of the random polypropylene is 70% by mass or more can be preferably used. As for the content rate of the said random polypropylene in the said resin material, 85 mass% or more is more preferable, 95 mass% or more is further more preferable, 98 mass% or more is especially preferable. For example, a single-layer plastic film made of the above random polypropylene can be preferably used as the film substrate.

  For the above film substrate, if necessary, light stabilizers such as radical scavengers and ultraviolet absorbers, antioxidants, antistatic agents, colorants (dyes, pigments, etc.), fillers, slip agents, anti-blocking agents. A known additive that can be used for a plastic film (typically, a film base of a protective sheet) used as a base in a general pressure-sensitive adhesive sheet, such as an agent, can be appropriately blended. Examples of light stabilizers include those containing benzotriazoles, hindered amines, benzoates and the like as active ingredients. Examples of the antioxidant include those containing alkylphenols, alkylene bisphenols, thiopropylene acid esters, organic phosphite esters, amines, hydroquinones, hydroxylamines and the like as active ingredients. Such additives can be used singly or in combination of two or more. The compounding quantity of an additive can be made into the same grade as the normal compounding quantity of the plastic film used as a base material in a general adhesive sheet.

  The thickness of the said film base material is not specifically limited, For example, it can be set as about 20 micrometers-200 micrometers. Usually, from the viewpoint of being easily deformed along the surface shape of the adherend, the thickness of the substrate is suitably 150 μm or less, preferably less than 120 μm, more preferably less than 100 μm, and even more preferably less than 80 μm. Reducing the thickness of the base material can be advantageous from the viewpoint that the blade member of the wiper described later is not easily caught by the adhesive sheet. On the other hand, the thickness of the base material is suitably 25 μm or more, preferably 30 μm or more, more preferably 40 μm or more from the viewpoints of performance to prevent damage to the window glass due to physical impact such as stepping stones and handling properties of the adhesive sheet. preferable.

  Such a film substrate can be manufactured by appropriately adopting a conventionally known general film forming method (extrusion molding, inflation molding, etc.). The surface of the film base on which the pressure-sensitive adhesive layer is provided (the pressure-sensitive adhesive layer-side surface) is treated to improve adhesion with the pressure-sensitive adhesive layer, such as corona discharge treatment, acid treatment, and ultraviolet irradiation treatment. Surface treatments such as plasma treatment and primer (primer) coating may be applied. The surface of the film base opposite to the surface on which the pressure-sensitive adhesive layer is provided (back surface) is subjected to surface treatment such as antistatic treatment, peeling treatment, water repellency treatment as necessary. Also good.

  In addition, on the film base, information on the use of the pressure-sensitive adhesive sheet for glass protection using the film base (vehicle type, type of window glass, etc.) and a mark for alignment of the pressure-sensitive adhesive sheet for glass protection are displayed. May be. The above-mentioned mark is used for, for example, alignment between a glass protective adhesive sheet and a window glass, or between glass protective adhesive sheets when a plurality of glass protective adhesive sheets are attached to one window glass. It can be a useful landmark. Such information and marks can be provided by a known method such as printing.

  The type of the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer is not particularly limited. For example, an acrylic pressure-sensitive adhesive, a rubber-based pressure-sensitive adhesive (natural rubber-based, synthetic rubber-based, mixed system thereof, etc.), a silicone-based pressure-sensitive adhesive, or a polyester-based pressure-sensitive adhesive Adhesive layer comprising one or more adhesives selected from various known adhesives such as adhesives, urethane adhesives, polyether adhesives, polyamide adhesives, and fluorine adhesives It can be. Here, the acrylic pressure-sensitive adhesive refers to a pressure-sensitive adhesive having an acrylic polymer as a base polymer (a main component of polymer components, that is, a component contained in excess of 50% by mass). This also applies to rubber-based and other adhesives. A preferable pressure-sensitive adhesive layer from the viewpoint of weather resistance, transparency, and the like includes a pressure-sensitive adhesive layer having an acrylic pressure-sensitive adhesive content of 50% by mass or more, more preferably 70% by mass or more, and still more preferably 90% by mass or more. It is done. The content of the acrylic pressure-sensitive adhesive may be more than 98% by mass, or may be a pressure-sensitive adhesive layer substantially made of an acrylic pressure-sensitive adhesive.

Such an acrylic pressure-sensitive adhesive (layer) can be formed using a pressure-sensitive adhesive composition having an acrylic polymer as a base polymer. The acrylic polymer typically includes an alkyl (meth) acrylate as a main monomer (a component occupying 50% by mass or more of the entire monomer), and further includes a submonomer that is copolymerizable with the main monomer. It is a copolymer of a monomer mixture. The monomer mixture may optionally contain other copolymerization components in addition to these main monomers and submonomers.
In the present specification, “(meth) acrylate” means acrylate and methacrylate comprehensively. Similarly, “(meth) acryloyl” refers to acryloyl and methacryloyl, and “(meth) acryl” refers to acryl and methacryl generically.

As the alkyl (meth) acrylate, for example, a compound represented by the following formula (1) can be preferably used.
CH ₂ = C (R ¹ ) COOR ² (1)
Here, R ¹ in the above formula (1) is a hydrogen atom or a methyl group. R ² is a chain alkyl group having 1 to 20 carbon atoms (hereinafter, such a range of the number of carbon atoms may be represented as “C _1-20 ”). From the viewpoint of the storage elastic modulus and the like of the pressure-sensitive adhesive, an alkyl (meth) acrylate in which R ² is a C _1-14 chain alkyl group is preferable, and R ² is an alkyl (meta) that is a C _1-10 chain alkyl group. ) Acrylate is more preferable, and alkyl (meth) acrylate in which R ² is a butyl group or a 2-ethylhexyl group is particularly preferable.

Examples of the alkyl (meth) acrylate having a C _1-20 chain alkyl group include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, and n-butyl (meth) ) Acrylate, isobutyl (meth) acrylate, s-butyl (meth) acrylate, pentyl (meth) acrylate, isopentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (Meth) acrylate, isooctyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, undecyl (meth) a Acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, octadecyl (meth) acrylate, nonadecyl (meth) acrylate, And eicosyl (meth) acrylate. These alkyl (meth) acrylates can be used alone or in combination of two or more. Particularly preferred alkyl (meth) acrylates include n-butyl acrylate (BA) and 2-ethylhexyl acrylate (2EHA).

  Typically, the pressure-sensitive adhesive sheet for protecting glass in the technology disclosed herein serves to protect the window glass of the automobile during storage and distribution of the automobile, and then the automobile is used for general consumers. It is used in such a manner that it is peeled off from the window glass before being used. For this reason, it is preferable that the said adhesive sheet for glass protection shows favorable removability with respect to the window glass for motor vehicles. This good re-peelability can be grasped as, for example, a performance that makes it difficult for an adhesive or the like to remain on the surface of the window glass when the pressure-sensitive adhesive sheet is peeled from the window glass.

A submonomer having copolymerizability with the main monomer, alkyl (meth) acrylate, can be useful for introducing a crosslinking point into the acrylic polymer or increasing the cohesive strength of the acrylic polymer. Increasing the cohesive strength of the acrylic polymer can advantageously contribute to improving the removability of the pressure-sensitive adhesive. As the submonomer, for example, the following functional group-containing monomer components can be used alone or in combination of two or more.
Carboxyl group-containing monomers: ethylenically unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid and crotonic acid; ethylenically unsaturated dicarboxylic acids such as maleic acid, itaconic acid and citraconic acid and anhydrides thereof (maleic anhydride, anhydrous) Itaconic acid).
Hydroxyl group-containing monomer: For example, hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate; Unsaturated alcohols such as vinyl alcohol and allyl alcohol.
Amide group-containing monomer: For example, (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N-butyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methylolpropane (meth) acrylamide, N-methoxymethyl (Meth) acrylamide, N-butoxymethyl (meth) acrylamide.
Amino group-containing monomer: for example, aminoethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, t-butylaminoethyl (meth) acrylate.
Monomers having an epoxy group: for example, glycidyl (meth) acrylate, methyl glycidyl (meth) acrylate, allyl glycidyl ether.
Cyano group-containing monomer: for example, acrylonitrile, methacrylonitrile.
Keto group-containing monomers: for example, diacetone (meth) acrylamide, diacetone (meth) acrylate, vinyl methyl ketone, vinyl ethyl ketone, allyl acetoacetate, vinyl acetoacetate.
Monomers having a nitrogen atom-containing ring: for example, N-vinyl-2-pyrrolidone, N-methylvinylpyrrolidone, N-vinylpyridine, N-vinylpiperidone, N-vinylpyrimidine, N-vinylpiperazine, N-vinylpyrazine, N-vinyl Pyrrole, N-vinylimidazole, N-vinyloxazole, N-vinylmorpholine, N-vinylcaprolactam, N- (meth) acryloylmorpholine.
Alkoxysilyl group-containing monomer: For example, 3- (meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropyltriethoxysilane, 3- (meth) acryloxypropylmethyldimethoxysilane, 3- (meth) acryloxy Propylmethyldiethoxysilane.

  The amount of the submonomer may be appropriately selected so as to achieve a desired cohesive force, and is not particularly limited. Usually, from the viewpoint of achieving a good balance between cohesive force and adhesiveness, the amount of the submonomer is suitably 20 parts by mass or less based on 100 parts by mass of the alkyl (meth) acrylate, and 15 parts by mass. The content is preferably as follows, and more preferably 10 parts by mass or less.

  For the purpose of increasing the cohesive strength of the acrylic polymer, other copolymer components other than the above-mentioned secondary monomer can be used. Examples of such copolymer components include vinyl ester monomers such as vinyl acetate and vinyl propionate; aromatic vinyl compounds such as styrene, substituted styrene (α-methylstyrene, etc.), vinyltoluene; cycloalkyl (meth) acrylate (cyclohexyl). (Meth) acrylate, cyclopentyl di (meth) acrylate, etc.), non-aromatic ring-containing (meth) acrylate such as isobornyl (meth) acrylate; aryl (meth) acrylate (for example, phenyl (meth) acrylate), aryloxyalkyl ( Aromatic ring-containing (meth) acrylates such as (meth) acrylate (eg phenoxyethyl (meth) acrylate), arylalkyl (meth) acrylate (eg benzyl (meth) acrylate); ethylene, propylene, isop Olefin monomers such as ethylene, butadiene and isobutylene; chlorine-containing monomers such as vinyl chloride and vinylidene chloride; isocyanate group-containing monomers such as 2- (meth) acryloyloxyethyl isocyanate; methoxyethyl (meth) acrylate and ethoxyethyl (meth) And alkoxy group-containing monomers such as acrylate; vinyl ether monomers such as methyl vinyl ether and ethyl vinyl ether; The amount of such other copolymerization component is not particularly limited as long as it is appropriately selected depending on the purpose and application, but is preferably about 10 parts by mass or less with respect to 100 parts by mass of alkyl (meth) acrylate, for example.

  The method for obtaining the acrylic polymer is not particularly limited, and various polymerization methods generally used as synthetic methods for acrylic polymers such as solution polymerization method, emulsion polymerization method, bulk polymerization method, suspension polymerization method and the like are applied. Thus, the polymer can be obtained. The acrylic polymer may be a random copolymer, a block copolymer, a graft copolymer, or the like. From the viewpoint of productivity and the like, a random copolymer is usually preferable.

The weight average molecular weight (Mw) of the acrylic polymer (regardless of the polymerization method) in the technique disclosed herein is preferably in the range of 10 × 10 ⁴ or more and 500 × 10 ⁴ or less, and 15 × 10 ⁴ or more. More preferably, it is in the range of 200 × 10 ⁴ or less, and more preferably in the range of 20 × 10 ⁴ or more and 150 × 10 ⁴ or less. An acrylic pressure-sensitive adhesive having such an acrylic polymer as a base polymer is preferable because it easily balances the adhesive force and the cohesive force. In the acrylic polymer obtained by the solution polymerization method, the Mw is more preferably in the range of 20 × 10 ⁴ or more and 100 × 10 ⁴ or less, and in the range of 30 × 10 ⁴ or more and 70 × 10 ⁴ or less. Particularly preferred. Here, Mw refers to a standard polystyrene equivalent value obtained by GPC (gel permeation chromatography).

  The acrylic pressure-sensitive adhesive composition may further contain a crosslinking agent in addition to the acrylic polymer as a base polymer. The kind of the crosslinking agent is not particularly limited, and can be appropriately selected from various crosslinking agents usually used in the pressure-sensitive adhesive field, for example, depending on the kind of the crosslinking functional group of the submonomer. Specific examples include isocyanate crosslinking agents, silane crosslinking agents, epoxy crosslinking agents, oxazoline crosslinking agents, aziridine crosslinking agents, metal chelate crosslinking agents, and the like. Since it is easy to form an adhesive layer having a good balance between adhesiveness and cohesive force, an isocyanate-based crosslinking agent can be preferably used. The amount of the crosslinking agent contained in the pressure-sensitive adhesive composition is not particularly limited, and can be set so as to obtain a desired cohesive force. Usually, it is appropriate to set it as 1-10 mass parts (preferably 1.5-6 mass parts, more preferably 2-5 mass parts) with respect to 100 mass parts of said acrylic polymers.

The above-mentioned pressure-sensitive adhesive composition includes, as optional components, an antistatic agent, a slip agent, an antiblocking agent, a leveling agent, a plasticizer, a filler, a colorant (pigment, dye, etc.), a dispersant, a stabilizer, a preservative, and aging. Various additives generally used in the pressure-sensitive adhesive field such as an inhibitor, a crosslinking accelerator, and a pH adjuster (typically an acid or a base) can be contained. The blending amount of such an additive can be approximately the same as the blending amount in a general pressure-sensitive adhesive sheet.
In addition, it is preferable not to mix | blend a tackifier with the said adhesive composition in consideration of transparency of a pressure-sensitive adhesive sheet for glass protection, weather resistance, non-fouling property (removability) of a glass surface, and the like.

  As a method of providing the pressure-sensitive adhesive layer on the substrate, a method of directly applying (typically applying) the pressure-sensitive adhesive composition to the substrate and curing it (direct method); ) Is applied with a pressure-sensitive adhesive composition and cured to form a pressure-sensitive adhesive layer on the surface, and the pressure-sensitive adhesive layer is bonded to a substrate and transferred to the substrate (transfer) Method) or the like. The curing treatment may be one or more treatments selected from drying (heating), cooling, crosslinking, additional copolymerization reaction, aging and the like. For example, the treatment of simply drying the pressure-sensitive adhesive composition containing a solvent (heating treatment, etc.), or the treatment of simply cooling (solidifying) the pressure-sensitive adhesive composition in a heated and melted state is also referred to herein as a curing treatment. Can be included. When the said hardening process contains two or more processes (for example, drying and bridge | crosslinking), these processes may be performed simultaneously and may be performed over multiple steps.

Application of the pressure-sensitive adhesive composition can be carried out using a conventional coater such as a gravure roll coater, reverse roll coater, kiss roll coater, dip roll coater, bar coater, knife coater, spray coater. From the viewpoint of promoting the crosslinking reaction and improving the production efficiency, the pressure-sensitive adhesive composition is preferably dried under heating. Depending on the type of support to which the composition is applied, for example, a drying temperature of about 40 to 150 ° C. can be employed. After drying, an aging treatment may be performed by holding at about 40 to 60 ° C. so that the crosslinking reaction further proceeds. The aging time may be appropriately selected according to the desired degree of crosslinking and the progress rate of the crosslinking reaction, and can be, for example, about 12 hours to 120 hours.
The thickness of the pressure-sensitive adhesive layer is not particularly limited, and can be, for example, about 0.5 μm to 20 μm, preferably about 0.5 μm to 15 μm, more preferably about 0.5 μm to 10 μm from the viewpoint of transparency. In addition, in this specification, the thickness of an adhesive layer means the average thickness measured by the method as described in the Example mentioned later.

  The pressure-sensitive adhesive layer is typically formed continuously over the entire surface of one surface of the substrate, but depending on the purpose and application, it may be formed in a regular or random pattern such as a dot or stripe. Good. In the glass protective adhesive sheet processed into an outer shape that fits inside the outer edge of the window glass for automobiles, an adhesive layer is continuously provided at least at the periphery of the outer shape from the viewpoint of preventing the intrusion of rainwater. It is preferable that From the viewpoint of exhibiting higher protection performance, it is more preferable that the pressure-sensitive adhesive layer is continuously formed over the entire range of one surface of the substrate in the outer shape.

  The pressure-sensitive adhesive sheet for protecting glass disclosed herein has water (sticking water) interposed between the pressure-sensitive adhesive layer and the adherend, and pushes the sticking water out of the sticking range of the pressure-sensitive adhesive sheet. It can be preferably affixed by a technique of pressure-bonding the pressure-sensitive adhesive sheet. By using the above-mentioned sticking water, the slipping property of the pressure-sensitive adhesive layer with respect to the adherend surface can be improved in the sticking process. By this, the wrinkle which arises at the time of sticking of an adhesive sheet can be prevented or reduced. There is no restriction | limiting in particular in the water used as said sticking water, For example, arbitrary waters, such as a tap water and ion-exchange water, can be used. A sticking water containing an appropriate amount of a surfactant in such water may be used.

  In such an affixing method, if the adhesive sheet is affixed while a large amount of the affixing water remains within the affixing range, the remaining affixed water evaporates to cause the adhesive sheet to float, thereby causing peeling or rainwater. There is a concern of intrusion. Further, the sticking water remaining in the adhesive sheet application range can cause distortion and glare in the visual field looking through the window glass in a state where the adhesive sheet is applied. A pressure-sensitive adhesive sheet that easily pushes water out of the pressure-sensitive adhesive sheet (that is, a glass protective pressure-sensitive adhesive sheet with good drainage) is preferable because it is suitable for application by a technique using the above-mentioned application water.

  The pressure-sensitive adhesive sheet for protecting glass disclosed herein can be preferably implemented in a mode in which the thickness (average thickness) of the pressure-sensitive adhesive layer is 10 μm or less from the viewpoint of drainage. According to this configuration, when the surface of the pressure-sensitive adhesive layer (smoothness of the adherend surface) is not provided with intentional irregularities such as grooves, and the surface of the pressure-sensitive adhesive layer has high surface smoothness (for example, pressure-sensitive adhesive) Even when the arithmetic average roughness (Ra) on the surface of the agent layer is 1.0 μm or less), good water drainage can be realized. From the viewpoint of obtaining better drainage, the thickness of the pressure-sensitive adhesive layer is preferably less than 10 μm, more preferably 7 μm or less, and particularly preferably 5 μm or less, and even more preferably less than 5 μm. In a preferred embodiment, the thickness of the pressure-sensitive adhesive layer can be 4 μm or less, for example, 3.5 μm or less.

  The shape of the surface of the pressure-sensitive adhesive layer (adherent adherend surface) is not particularly limited as long as the preferable haze value described above can be realized. From the viewpoint of obtaining a good field of view in an automobile in which an adhesive sheet for protecting glass is adhered to a window glass, it is advantageous that the surface of the adhesive layer is not provided with intentional irregularities and has high surface smoothness. It is. From this viewpoint, the arithmetic average roughness (Ra) of the surface of the pressure-sensitive adhesive layer (adhered surface) is preferably 1.0 μm or less, preferably 0.7 μm or less, and 0.5 μm or less. It is more preferable that The lower limit of the arithmetic average roughness (Ra) of the surface of the pressure-sensitive adhesive layer is not particularly limited, but it is usually suitably 0.05 μm or more from the viewpoint of ease of production and the like. The arithmetic average roughness (Ra) of the pressure-sensitive adhesive layer is measured by the method described in Examples described later. The arithmetic average roughness (Ra) of the pressure-sensitive adhesive layer is adjusted by, for example, the coating conditions, viscosity, drying conditions of the pressure-sensitive adhesive composition, the surface condition of the release liner described later (for example, arithmetic average roughness (Ra)), and the like. be able to.

  The pressure-sensitive adhesive sheet for protecting glass disclosed herein may be processed into an outer shape that fits inside the outer edge of the outer surface of the window glass for automobiles. For such a glass protective pressure-sensitive adhesive sheet having an outer shape, for example, a predetermined general-purpose pressure-sensitive adhesive sheet (hereinafter also referred to as a pressure-sensitive adhesive sheet raw material) is prepared, and the pressure-sensitive adhesive sheet raw material is cut into a desired outer shape. Can be prepared. The original pressure-sensitive adhesive sheet is typically a long and wide sheet, and can be prepared, for example, in the form of a roll. By unwinding the pressure-sensitive adhesive sheet from the roll and punching or cutting it into a desired shape, it is possible to easily prepare the pressure-sensitive adhesive sheet for glass protection having the outer shape. After the said adhesive sheet original fabric is once cut | disconnected by affordable size, you may cut out the glass sheet adhesive sheet of the said external shape from there. The affordable size is, for example, cutting out a pair of adhesive sheets (for example, one center sheet and three edge sheets used in the first embodiment described later) used to protect one window glass. It can be a possible size.

  The pressure-sensitive adhesive sheet for protecting glass disclosed here is, for example, as shown in FIG. 2, a pressure-sensitive adhesive sheet with an auxiliary sheet in which another pressure-sensitive adhesive sheet (auxiliary sheet) 7 is attached to the back surface 6B of the pressure-sensitive adhesive sheet 6 shown in FIG. 100 may be configured. The auxiliary sheet 7 includes an auxiliary base material 72 and an auxiliary pressure-sensitive adhesive layer 74 provided on one surface thereof. The surface of the auxiliary pressure-sensitive adhesive layer 74 is attached to the back surface 6B of the pressure-sensitive adhesive sheet 6 so as to be removable from the back surface 6B. The auxiliary sheet 7 is typically laminated over the entire range of the back surface 6B of the adhesive sheet 6.

Such an adhesive sheet with an auxiliary sheet 100 is easy to handle because the auxiliary sheet 7 enhances the shape stability of the glass protective adhesive sheet 6. In addition, by sticking the glass protective adhesive sheet 6 to the adherend in the form of the adhesive sheet with an auxiliary sheet 100, the back surface of the auxiliary sheet 7 is prevented while preventing the adhesive sheet 6 from being locally stretched or scratched. Can be firmly stressed. By this, it can become easy to affix the adhesive sheet 6 appropriately to a to-be-adhered body.
Since the auxiliary sheet 7 is detachably attached to the back surface 6B of the pressure-sensitive adhesive sheet 6, after the pressure-sensitive adhesive sheet with auxiliary sheet 100 is attached to the adherend, the glass protective pressure-sensitive adhesive sheet 6 is left on the surface of the adherend. Thus, the auxiliary sheet 7 can be peeled (removed). The remaining glass protective pressure-sensitive adhesive sheet 6 can exhibit excellent transparency, curved surface followability and anti-floating property. Therefore, according to the pressure-sensitive adhesive sheet with an auxiliary sheet 100, the handleability, the curved surface followability, and the anti-floating property of the glass protective pressure-sensitive adhesive sheet 6 can be achieved at a higher level. Moreover, the transparency of the window glass on which the adhesive sheet 6 is affixed can be improved by peeling the auxiliary sheet 7.

  Before the glass protective adhesive sheet disclosed herein is attached to the adherend, for example, as shown in FIG. 3, the glass protective adhesive sheet 6 has an adhesive adherent surface (adhesive face) 6 </ b> A on the adherend adherent surface (adhesive face). You may comprise the adhesive sheet 200 with a release liner with which the release liner 8 was laminated | stacked. According to such a pressure-sensitive adhesive sheet 200 with a release liner, an operation of cutting the pressure-sensitive adhesive sheet original fabric into a desired outer shape can be performed efficiently. Moreover, it is preferable also from a viewpoint that the adhesive sheet 6 for glass protection cut off can be stored compactly until use. Also, the glass protective pressure-sensitive adhesive sheet 6 in the form of the pressure-sensitive adhesive sheet 200 with a release liner is easy to handle because the shape stability of the glass protective pressure-sensitive adhesive sheet 6 is assisted by the release liner 8. Easy to carry to place. The glass protective pressure-sensitive adhesive sheet 6 constituting such a pressure-sensitive adhesive sheet with release liner 200 is then peeled off the release liner 8 to expose the adherend pasting surface 6A, and the adherend pasting surface 6A is used as the adherend. Used by crimping.

  As the release liner, various types of paper (which may be paper having a resin laminated on the surface), a plastic film, and the like can be used without particular limitation. When a plastic film is used as the release liner, preferred examples of the resin component constituting the plastic film include polyolefin resin, polyester resin (PET, etc.), polyamide resin, polycarbonate resin, polyurethane resin and the like. It may be a plastic film made of a resin material containing one kind of such resin alone, or may be a plastic film made of a resin material in which two or more kinds of resins (for example, PE and PP) are blended. The structure of the plastic film may be a single layer or a multilayer structure of two or more layers. Such a plastic film for a release liner can be produced by appropriately adopting a general film forming method, similarly to the plastic film for a substrate.

  The thickness of the release liner is not particularly limited, and may be, for example, about 5 μm to 500 μm (preferably about 10 μm to 200 μm, for example, about 30 μm to 200 μm). On the release surface of the release liner (the surface disposed in contact with the surface of the pressure-sensitive adhesive layer), a conventionally known release agent (for example, a general silicone-based, long-chain alkyl-based, fluorine-based release agent, etc.) is used as necessary. A peeling treatment with an agent) may be performed. The back surface of the release surface may or may not be subjected to a release treatment, and may be subjected to a surface treatment other than the release treatment.

Although not particularly limited, the arithmetic average roughness (Ra) of the surface of the release liner (the surface on the side of the pressure-sensitive adhesive layer) is suitably 2.0 μm or less, and 1.5 μm or less. Is preferable, 1.0 micrometer or less is more preferable, and 0.7 micrometer or less (for example, 0.5 micrometer or less) is further more preferable. The lower limit of the arithmetic average roughness (Ra) of the surface of the release liner is not particularly limited, but it is usually suitably 0.05 μm or more from the viewpoint of manufacturability and the like.
The arithmetic average roughness (Ra) of the surface of the release liner can be measured as follows. That is, the pressure-sensitive adhesive layer (fixing pressure-sensitive adhesive layer) for fixing the measurement sample is formed on the surface of the slide glass (manufactured by Matsunami Glass Industry Co., Ltd., trade name “White edge polishing No. 2, S-1112”). To do. A release liner to be measured is disposed on the fixing pressure-sensitive adhesive layer so that the measurement target surface is on the upper side. Further, a non-contact three-dimensional surface shape measuring device manufactured by Veeco, model “Wyko NT-3300” (VSI method. Objective lens 2.5 times, internal lens 0.55 times, Backscan: 10 μm, Length: 15 μm, threshold: Arithmetic mean roughness (Ra) (average value of MD and TD) is measured within a range of 5 mm × 5 mm using 1%, Window Filtering: None. The measurement is carried out with n = 5, and the average value of three data excluding the upper limit value and the lower limit value is obtained.

  The pressure-sensitive adhesive sheet for protecting glass disclosed herein satisfies both of the above conditions (B) and (C), so that it can be easily attached along the outer surface of the window glass for automobiles, and the temperature after application. Floating due to change is less likely to occur. Therefore, it is preferably used in a mode in which it is attached to an automotive window glass in a flat shape (two-dimensional shape), and good protective performance can be exhibited. In other words, a flat (two-dimensional) pressure-sensitive adhesive sheet is used as it is without being molded into a three-dimensional shape in advance (for example, by heat molding) in order to approximate the shape of the outer surface of the window glass. Can do. According to this use mode, the cost required for attaching the pressure-sensitive adhesive sheet for glass protection can be effectively reduced by eliminating the need for prior thermoforming or the like. The ability to use planar adhesive sheets as they are for pasting is also preferable from the viewpoints of storage stability and portability of these sheets. However, considering the efficiency of pasting work and the protection performance after pasting, etc., pasting a part or all of the glass protective adhesive sheet disclosed here into a three-dimensional shape beforehand Uninhibited and use in such aspects may also be included within the scope of the technical ideas disclosed herein.

  The pressure-sensitive adhesive sheet for protecting glass disclosed herein can be used for protecting window glass of each part of an automobile. For example, it may be preferably applied to a front window glass and a rear window glass as in first to third embodiments described later, and may be applied to a side window glass, a quarter window glass, a stationary window glass, and the like. Among them, a preferred application object is a front window glass. Because the front window glass has a large area among the window glass of automobiles, it has a high probability of hitting pebbles, etc., and it is required to have durability that does not drown or twist even if the wiper is moved. This is because it is easy to enter and has a large impact on the product value. In general, passenger cars tend to have a larger window glass curvature due to their higher design than buses and trucks. Therefore, the pressure-sensitive adhesive sheet for protecting glass disclosed herein can be particularly preferably applied to the protection of passenger car window glass.

  By sticking the adhesive sheet for glass protection disclosed here to the window glass for automobiles, the window glass with the adhesive sheet for glass protection is obtained. When the window glass is a window glass of an automobile that has already been completed, an automobile having a window glass with an adhesive sheet for protecting glass can be obtained by attaching the adhesive sheet for protecting glass. In addition, when the window glass is not yet assembled to an automobile or is assembled to an incomplete automobile, the automobile is completed after the glass protective adhesive sheet is attached. An automobile having a window glass with a sheet is obtained. Therefore, as another aspect of the pressure-sensitive adhesive sheet for glass protection disclosed herein, a method for attaching a pressure-sensitive adhesive sheet for glass protection, a window glass with a pressure-sensitive adhesive sheet for glass protection and a method for producing the same, and a window glass with a pressure-sensitive adhesive sheet for glass protection, An automobile having the same and a method for manufacturing the same are provided.

  The pressure-sensitive adhesive sheet for protecting glass disclosed herein can be preferably used as a center sheet that covers the central part of the window glass for automobiles. The shape and size of the center sheet are not particularly limited, and may be any shape and size that can be accommodated inside the outer edge of the window glass in relation to the window glass to which the center sheet is attached. The said center sheet | seat has the external shape which can cover the whole at least said center part of the window glass for motor vehicles. The external shape which can further cover the area | region outside the said center part may be sufficient. For example, the outer shape which a part of said center sheet covers a part of peripheral part of a window glass may be sufficient. By covering the center portion of the window glass with such a center sheet, the pasting range including the center portion can be suitably protected from damage due to stepping stones or the like.

  The pressure-sensitive adhesive sheet for protecting glass disclosed herein may be in a form processed (for example, punched) into the outer shape of the center sheet as described above. Since such a center sheet has a low haze value, a good field of view can be secured in the window glass to which the center sheet is attached. Moreover, since the balance between the curved surface followability and the handleability is good, it is easy to attach appropriately along the outer surface of the window glass, and it is possible to effectively suppress the occurrence of floating and wrinkles after application. Therefore, it is possible to continuously exhibit good protection performance by preventing peeling and intrusion of rainwater.

The area of the center sheet is not particularly limited as long as it is less than 100% of the area of the outer surface of the window glass to be pasted by the center sheet. The ratio of the area of the center sheet to the area of the outer surface of the window glass (hereinafter referred to as the window glass coverage R _C by the center sheet) is, for example, 95% or less (typically less than 95%). It is possible to make it 90% or less. When the coverage _RC is small, it tends to be easier to appropriately attach the center sheet to the window glass. From this point of view, the coverage _RC is more preferably 85% or less. The lower limit of the coverage ratio _RC is not particularly limited as long as the center sheet is an area that can cover the entire center portion of the window glass. Usually, the coverage _RC is preferably 50% or more, more preferably 60% or more, and further preferably 70% or more.

  It is preferable that the one side of the center sheet is provided with a protruding portion in which the contour line of the center sheet partially protrudes outward. The protrusion is preferably formed so as to protrude toward the right side or the left side of the window glass when the center sheet is attached to the window glass for an automobile. Moreover, it is preferable to affix a center sheet in such an orientation. In general, the peripheral edge (side edge) along the right side and the left side of the window glass often has a strongly curved shape (a shape with a large curvature) as compared with the central part of the window glass. The protruding portion of the center sheet can be appropriately attached to such a side portion. Therefore, by providing such a protruding portion, a part (protruding portion) of the center sheet is attached to a position closer to one side without greatly impairing the ease of attaching the center sheet. Can do. This is particularly significant when the window glass to which the wiper is applied is to be protected (applied object) as will be described later.

  In a preferred embodiment, one side of the center sheet has protrusions that project the outline of the center sheet partially outward (preferably toward the right or left side of the window glass). Two or more are provided at intervals. In the center sheet having such a shape, a contour line of the center sheet is a valley part that is partially recessed inward of the center sheet between two adjacent protrusions of the protrusions. By utilizing this valley portion, it is possible to escape (absorb) the strain that occurs because the center sheet conforms to the surface shape of the side portion of the window glass. Thereby, generation | occurrence | production of a wrinkle can be prevented and it can become easy to paste the said center sheet | seat appropriately.

The center sheet preferably includes a trough having a depth of 50 mm or more between two adjacent protrusions of the two or more protrusions. Here, the depth of the valley means a straight line connecting the tips of the two projections on either side of the valley portion, the distance L _D between the parallel straight lines and street the straight line bottom of the valley. According to the center sheet having the valley portion having such a depth, the effect of releasing the strain can be better exhibited. When the wiper of the applicable joining target window glass is to be described later, it is particularly meaningful to the depth L _D of the valley or more 50 mm.

  The pressure-sensitive adhesive sheet for protecting glass disclosed herein can also be preferably used as an edge sheet that is attached to the peripheral edge of an automobile window glass and covers at least a part of the peripheral edge. The edge sheet may be affixed to the window glass so that a part of the edge sheet covers an area on the inner side (center side) than the peripheral edge. However, the edge sheet is preferably attached so as not to cover the central portion. In other words, the edge sheet is preferably affixed to the window glass so that the inner end thereof (the end on the center part side of the window glass) is located outside the center part.

  The pressure-sensitive adhesive sheet for protecting glass disclosed herein may be in a form processed (such as punching or cutting) into the outer shape of such an edge sheet. Such an edge sheet has a good balance between curved surface followability and handleability, so that it is easy to apply appropriately along the surface shape of the peripheral edge of the window glass, and effectively suppresses the occurrence of float and wrinkles after application. be able to. Therefore, it is possible to continuously exhibit good protection performance by preventing peeling and intrusion of rainwater. Moreover, since a haze value is low, a favorable visual field can be ensured at the peripheral portion of the window glass to which the edge sheet is attached.

  The edge sheet preferably has a width of 300 mm or less. By reducing the width of the edge sheet, it becomes easy to appropriately apply the edge sheet to the peripheral edge portion that is generally more curved than the center portion. By this, the working time for sticking the adhesive sheet for glass protection appropriately can be shortened effectively. From this viewpoint, the width of the edge sheet is more preferably 250 mm or less, and further preferably 200 mm or less.

  The pressure-sensitive adhesive sheet for protecting glass disclosed herein can be preferably used in a mode in which the center sheet and the edge sheet as described above are combined and attached to the outer surface of the window glass. Thus, by sticking the adhesive sheet for glass protection into the center sheet and the edge sheet, it can be easy to attach each sheet appropriately along the shape of the outer surface of the window glass. If sticking of the adhesive sheet for glass protection becomes easy, the work time required for the sticking can be shortened. Therefore, the adhesive sheet for glass protection can be appropriately affixed in a shorter working time.

  Of the pressure-sensitive adhesive sheets for protecting glass used for protecting one window glass, the center sheet is preferably composed of one pressure-sensitive adhesive sheet. Covering the central part of the window glass with a single (single) center sheet reliably prevents rainwater from entering the central part, and highly prevents the center from causing water marks. can do. Since the central portion of the window glass easily enters the field of view of the person using the automobile and greatly affects the commercial value, it is particularly meaningful that the generation of water marks in the central portion can be effectively prevented.

  Further, as the edge sheet, only one adhesive sheet may be used, or two or more adhesive sheets may be used in combination. When two or more adhesive sheets are used as the edge sheet, each adhesive sheet may have a shape along one side of the outer edge of the window glass, or may have a shape along two or more adjacent sides. For example, an aspect in which one edge sheet having a shape along one of the outer edges of the window glass is used, or two, three, or four edges having a shape along each one of the outer edges of the window glass. An embodiment using a combination of sheets can be preferably adopted.

  These center sheets and edge sheets can be appropriately affixed along the shape of the outer surface of the window glass without taking the effort of forming them into a three-dimensional shape in advance. However, it is not hindered that the edge sheet or the center sheet is partly or wholly formed into a three-dimensional shape in advance in consideration of the efficiency of the pasting work and the protection performance after the pasting.

  The center sheet and the edge sheet are preferably attached to the window glass so that the inner edge of the edge sheet and the peripheral edge of the center sheet overlap. By this, rain water infiltration from the inner edge part of an edge sheet | seat or the peripheral part of a center sheet | seat can be suppressed effectively. This is because the interface where the center sheet and the edge sheet overlap is a gap between the base material of the sheet located below (window glass side) and the adhesive layer of the sheet located above, that is, a gap between the resin and the resin. Because. In general, the gap between the resin and the resin tends to be less likely to allow water to enter than the gap between the resin and the glass. Therefore, by overlapping the inner edge portion of the edge sheet and the peripheral edge portion of the center sheet, the rainwater intrusion can be suppressed as compared with the case where the inner edge portion or the peripheral edge portion is directly attached to the window glass.

  The order of pasting the center sheet and the edge sheet (sheet stacking order) is not particularly limited. For example, the center sheet may be pasted after the edge sheet is pasted, or the edge sheet may be pasted after the center sheet is pasted. When a plurality of edge sheets are used, a center sheet may be pasted after a part of the edge sheets are pasted, and then the remaining edge sheets may be pasted. It is particularly preferable that after the edge sheet is pasted, the peripheral edge of the center sheet is laminated and pasted on the inner edge of the edge sheet.

Although it does not specifically limit, the adhesive force of the center sheet with respect to the back surface of an edge sheet | seat can be 0.05 N / 20mm or more, for example, and it is preferable that it is 0.1 N / 20mm or more. This makes it possible to prevent rainwater from entering and peeling off at a higher level at the place where the layers are stacked and pasted as described above. The upper limit value of the adhesive strength of the center sheet to the back surface of the edge sheet is not particularly limited. From the viewpoints of handling at the time of pasting, workability when peeling and removing from the window glass after finishing the protective purpose, prevention of adhesive residue, etc., it is usually appropriate that the adhesive strength is 5.0 N / 20 mm or less. It is preferable to be 3.0 N / 20 mm or less.
The adhesive force of the center sheet to the back surface of the edge sheet can be measured as follows. That is, the edge sheet is fixed to the SUS304 stainless steel plate with the double-sided pressure-sensitive adhesive sheet so that the back surface of the edge sheet is outside. A center sheet is cut into a width of 20 mm to prepare a test piece. In a standard environment of 23 ° C. and 50% RH, the test piece is attached to the back surface of the edge sheet by reciprocating a 2 kg roller. After holding this in the standard environment for 30 minutes, using a universal tensile compression tester (device name “Tension compression tester, TG-1kN” manufactured by Minebea Co., Ltd.), according to JIS Z0237 (2004), 180 degree peeling adhesive strength (N / 20 mm) is measured under the condition of a pulling speed of 300 mm / min.

  By the way, in general, an automobile includes a wiper for wiping off deposits (water, dirt, etc.) on the surface of the window glass. The wiper includes a blade member that reciprocates in a predetermined wiping area along the surface of the window glass. A typical automobile includes a wiper for wiping at least the surface of a windshield (hereinafter sometimes abbreviated as “windshield”). In addition to the wiper applied to the windshield as described above, there is also an automobile including a wiper applied to another window glass such as a rear window glass (hereinafter sometimes abbreviated as “rear glass”). The pressure-sensitive adhesive sheet for protecting glass disclosed herein is a mode in which the peripheral edge of the center sheet is laminated and pasted on the inner edge of the edge sheet as described above, and thus for protecting the glass for window glass to which the wiper is applied. It can be preferably used as an adhesive sheet. Thus, by laminating the peripheral edge of the center sheet on the inner edge of the edge sheet, the blade member is not easily caught on the inner edge of the edge sheet even if the wiper is operated after application. Therefore, even if the wiper is operated, the glass protective adhesive sheet is hardly peeled off or twisted, and good protection performance can be maintained.

  Thus, what has the said protrusion part can be employ | adopted preferably as a center sheet affixed on the window glass to which a wiper is applied. In this case, it is preferable that the center sheet is attached so that the blade member is positioned across the projecting portion at a position where the blade member is closest to one side of the window glass (closest position). The closest position can generally be a turn-back position in the reciprocating movement of the blade member. For this reason, the load which the blade member gives to the pressure-sensitive adhesive sheet for glass protection tends to be high at the closest position. By supporting the blade member on the protruding portion of the center sheet at the closest position, the load applied to the edge sheet by the blade member can be reduced. Accordingly, it is possible to prevent peeling and twisting of the edge sheet and maintain good protection performance.

  From the viewpoint of further reducing the load applied to the edge sheet by the blade member, a center sheet in which two or more protrusions are provided at an interval is used, and the blade member has the two or more protrusions at the closest position. The center sheet may be pasted so as to be located across the valley (across the valley). According to such an aspect, the blade member at the closest position can be more stably supported by the two or more protrusions. Therefore, the load that the blade member imposes on the edge sheet can be more effectively reduced.

  The center sheet is preferably attached so that at least a part of the blade member is always positioned on the center sheet in the wiping region. By this, the load which the said blade member gives to the adhesive sheet for glass protection can be reduced, and peeling and twist of this adhesive sheet can be prevented, and favorable protective performance can be maintained.

  Hereinafter, the preferable usage form of the adhesive sheet for glass protection disclosed here is demonstrated, referring drawings.

(First embodiment)
FIG. 4 is a plan view showing a main part of an automobile (passenger car) 10 including a windshield 20 to which the glass protective adhesive sheet 1 disclosed herein is attached. FIG. 5 and FIG. 6 are explanatory diagrams showing a procedure for attaching the glass protective adhesive sheet 1 to the windshield 20.

The windshield 20 is attached to the opening of the body of the automobile 10 via the window molding 12 mounted on the outer periphery thereof. The glass protective adhesive sheet 1 may be attached before the window molding 12 is attached to the windshield 20, and after the window molding 12 is attached to the windshield 20 and before the windshield 20 is attached to the automobile 10. Or after the windshield 20 is attached to the automobile 10. For example, from the viewpoint of ease of alignment with the outer end 26 of the windshield 20 and ease of pasting work, after the window molding 12 is mounted on the windshield 20, the glass is protected before the windshield 20 is attached to the automobile 10. A mode in which the pressure-sensitive adhesive sheet 1 is attached can be preferably adopted.
For convenience of explanation, FIGS. 5 and 6 show only the portion inside the outer end 26 of the windshield 20 in FIG. 4. Similarly in FIGS. 9 and 10 showing second and third embodiments to be described later, only the portions inside the outer ends 26 and 326 of the window glasses 20 and 320 are displayed.

  The glass protective pressure-sensitive adhesive sheet 1 is composed of an edge sheet 2 that is attached to the peripheral edge portion 22 of the windshield 20 and a center sheet 4 that is attached from above the edge sheet 2 and covers the central portion 24 of the windshield 20. ing. The edge sheet 2 is composed of three adhesive sheets. That is, the right edge sheet 2A attached to the peripheral edge portion 22 along the right side 26A of the outer edge 26 of the windshield 20, the left edge sheet 2B attached to the peripheral edge portion 22 along the left side 26B, and the peripheral edge along the upper edge 26C. The upper edge sheet 2 </ b> C is attached to the portion 22. On the other hand, the center sheet 4 consists of one adhesive sheet. In the present embodiment, edge sheets 2A, 2B, 2C and a center sheet 4 each prepared in a predetermined shape are prepared, and these sheets are attached to the windshield 20 for use.

  Specifically, as shown in FIG. 5, first, the right edge sheet 2 </ b> A and the left edge sheet 2 </ b> B are respectively attached to the peripheral edge portions 22 along the right side 26 </ b> A and the left side 26 </ b> B of the windshield 20. The order of attaching the right edge sheet 2A and the left edge sheet 2B is not particularly limited, and either may be attached first. Alternatively, the right edge sheet 2A and the left edge sheet 2B may be attached in parallel.

  In FIG. 5, the range of the peripheral portion 22 and the range of the central portion 24 in the windshield 20 are shown together. That is, the peripheral edge portion 22 is a frame-shaped region along the outer end 26 of the windshield 20, and the shorter length (the center line L 1 in the width direction and the center line L 2 in the height direction of the windshield 20 ( Here, it is a region having a width corresponding to 10% of the length of the center line L1. The center portion 24 is centered on the intersection of the center line L1 in the width direction of the windshield 20 and the center line L2 in the height direction, and has a shorter length (that is, the center line) of the center line L1 and the center line L2. This is a region inside a circle having a diameter corresponding to 30% of the length of L1.

  The right edge sheet 2A is formed in a band shape and has a length slightly shorter than the right side 26A of the windshield 20. The length of the right edge sheet 2A can be, for example, 0.5-30% (preferably 5-20%) shorter than the length of the right side 26A. The right side and the lower side of the right edge sheet 2A have shapes that are generally adapted to the outer ends 26 (the right side 26A and the lower side 26D) of the corresponding windshield 20. The left side (inner end) of the right edge sheet 2A is generally linear. The upper edge of the right edge sheet 2A is inclined with respect to the width direction of the right edge sheet 2A so that the length of the right edge sheet 2A decreases from the left side to the right side. That is, the length of the portion of the right edge sheet 2A that is attached to the outer end side of the windshield 20 is smaller than the length of the portion that is attached to the center side. By making the right edge sheet 2A into such a shape, it is easier to appropriately paste the right edge sheet 2A. When it is attached to the windshield 20 having a shape in which the curvature increases as it approaches the outer end, it is particularly significant that the right edge sheet 2A has the above shape.

  The width of the right edge sheet 2A is preferably 300 mm or less, more preferably 250 mm or less, and even more preferably 200 mm or less. By reducing the width of the right edge sheet 2A, it is possible to more easily attach the right edge sheet 2A appropriately. Further, the width of the right edge sheet 2A is preferably 50 mm or more, and more preferably 70 mm or more from the viewpoint of handleability. Increasing the width of the right edge sheet 2A is also preferable from the viewpoint of better exhibiting the effect of using the right edge sheet 2A and the center sheet 4 in combination. The ratio (length / width) between the length and width of the right edge sheet 2A is not particularly limited. From the viewpoint of handleability and the like, the length / width ratio of the right edge sheet 2A can be set to, for example, about 2 to 30, and normally about 3 to 20 is appropriate.

  Here, the length of the right edge sheet 2A refers to the maximum length from one end to the other end in the longitudinal direction. Further, the width of the right edge sheet 2A refers to a width of a portion formed to have a substantially constant width except for a portion where the width fluctuates greatly near the upper side and the lower side. In the example shown in FIGS. 4 to 6, the length of the right edge sheet 2A on the left side (inner end) is referred to as the length of the right edge sheet 2A, and the width of the right edge sheet 2A near the center in the longitudinal direction is the right edge sheet. The width is 2A.

  The attachment of the right edge sheet 2A is such that the distance from the right side to the outer end 26 of the windshield 20 is 0 mm or more and 30 mm or less (preferably more than 0 mm but 20 mm or less, more preferably more than 0 mm and 15 mm or less). It is preferable to carry out. It is preferable to process the right edge sheet 2A so that it can be attached in this manner. The distance from the lower side of the right edge sheet 2A to the outer end 26 of the windshield 20 is also preferably in the above range. It is particularly preferable to prepare and paste the right edge sheet 2A so that the distances from the right side and the lower side of the right edge sheet 2A to the outer end 26 of the windshield 20 are all in the above range.

  By shortening the distance from the right edge sheet 2 </ b> A to the outer end 26 of the windshield 20, the area where the outer surface 20 </ b> A of the windshield 20 is exposed at this portion can be reduced, and higher protection performance can be exhibited. For example, damage to a portion where the windshield 20 is exposed between the right edge sheet 2A and the outer end 26 of the windshield 20 and intrusion of rainwater from the right side of the right edge sheet 2A can be better prevented. .

  In this embodiment, the glass protective adhesive sheet 1 is divided into the center sheet 4 and the edge sheet 2 and attached, so that each sheet is compared with the conventional glass protective adhesive sheet configured as a single adhesive sheet as a whole. Is easy to handle. This can advantageously contribute to sticking each sheet easily and with high positional accuracy. In particular, the right edge sheet 2A used in the present embodiment is formed in a strip shape corresponding to one side (here, the right side 26A) of the outer edge 26 of the front window 20, so that two adjacent sides (for example, the upper side and the right side) Compared with one L-shaped edge sheet corresponding to (side), alignment with the outer end 26 is easy. Therefore, the edge sheet 2A can be accurately attached to a desired position within a practical work time. The same can be said for the left edge sheet 2B and the upper edge sheet 2C.

  The left edge sheet 2B may have the same shape as the right edge sheet 2A, except that the left side and the lower side thereof have a shape that is generally compatible with the left side 26B and the lower side 26D of the windshield 20. The left edge sheet 2B is preferably pasted so that the distance from the left side (more preferably the left side and the lower side) to the outer end 26 of the windshield 20 is within the preferred range of the right edge sheet 2A described above. It is preferable to prepare the shape of the left edge sheet 2B so that it can be attached in this way. When the shape of the windshield 20 is bilaterally symmetric, the outer shape of the left edge sheet 2B may be a shape in which the right edge sheet 2A is turned over.

  Next, as illustrated in FIG. 6, the upper edge sheet 2 </ b> C is attached to the peripheral edge portion 22 along the upper side of the windshield 20. The upper side of the upper edge sheet 2 </ b> C has a shape that roughly matches the upper side 26 </ b> C of the outer end 26 of the windshield 20. The upper edge sheet 2C is formed in a strip shape in which the upper side and the lower side are substantially parallel.

  The width of the upper edge sheet 2C is preferably 300 mm or less, more preferably 250 mm or less, and even more preferably 200 mm or less. By reducing the width of the upper edge sheet 2C, it is possible to more easily attach the upper edge sheet 2C appropriately. In addition, from the viewpoint of better exhibiting the effect of using the upper edge sheet 2C and the center sheet 4 in combination and from the viewpoint of handleability of the upper edge sheet 2C, the width of the upper edge sheet 2C is preferably 50 mm or more, 70 mm or more is more preferable, and 100 mm or more is more preferable. Although not particularly limited, from the viewpoint of handleability of the upper edge sheet 2C, the ratio of the length and width of the upper edge sheet 2C (length / width) can be, for example, about 3 to 30, Usually, about 5-30 is appropriate.

  In the present embodiment, the upper side of the upper edge sheet 2C is directly attached to the outer surface 20A of the windshield 20 over its entire length. Further, both ends of the upper edge sheet 2C in the longitudinal direction are at the upper ends of the right edge sheet 2A and the left edge sheet 2B that are already attached to the windshield 20, from the back surfaces (outer side surfaces) of the edge sheets 2A and 2B. It is stuck so as to straddle the outer surface 20A of the windshield 20. In view of the shape of the windshield 20, each edge sheet 2 (edge sheets 2 </ b> A, 2 </ b> B, 2 </ b> C) may be prepared so that it can be attached in this manner. By directly attaching the upper edge sheet 2C to the windshield 20 on the upper side 26C side of the windshield 20 from the upper edges of the right edge sheet 2A and the left edge sheet 2B, the upper edges and edge sheets of the right edge sheet 2A and the left edge sheet 2B An event that rainwater enters from the joint of 2A, 2B, and 2C can be effectively prevented. Thereby, the improvement of workability | operativity by dividing | segmenting the edge sheet | seat 2 into several sheets, the improvement of a positional accuracy, and ensuring of the protection performance of the windshield 20 are simultaneously realizable at a high level. The upper edge sheet 2C is positioned below the upper edge sheet 2C until the upper end of the right edge sheet 2A extends from the left side to the right side, and the upper end of the left edge sheet 2B extends upward from the right side to the left side. It is preferable to affix so that it may be located under the edge sheet 2C. This can better prevent rainwater from entering.

  The upper edge sheet 2C is attached so that the distance from the upper side to the upper side 26C of the windshield 20 is 0 mm or more and 30 mm or less (preferably more than 0 mm but 20 mm or less, more preferably more than 0 mm and 15 mm or less). It is preferable. It is preferable to prepare the upper edge sheet 2C so that it can be attached in this manner. By shortening the distance from the outer edge of the upper edge sheet 2C to the upper side 26C of the windshield 20, the area where the outer surface 20A of the windshield 20 is exposed at this portion can be reduced, and higher protection performance can be exhibited. . It is more preferable that the distances from the right side and the left side of the upper edge sheet 2C (that is, both ends in the longitudinal direction) to the outer end 26 (right side 26A, left side 26B) of the windshield 20 are also in the above range.

  The right edge sheet 2A, the left edge sheet 2B and the upper edge sheet 2C constituting the edge sheet 2 have a distance from the outer edge of the edge sheet 2 to the outer edge of the windshield of 0 mm or more and 30 mm or less (preferably more than 0 mm and 20 mm). In the following, it is preferably pasted so as to be more than 0 mm and 15 mm or less. It is preferable to produce (process) the edge sheets 2A, 2B, and 2C so that they can be attached in this manner. By shortening the distance from the outer edge of the edge sheet 2 to the outer edge 26 of the windshield 20, the area where the outer surface 20A of the windshield 20 is exposed at this portion can be reduced, and higher protection performance can be exhibited. .

  The edge sheets 2A, 2B, and 2C are pasted so that the distance from the inner end of each sheet to the outer end 26 of the windshield 20 is 50 mm to 300 mm (more preferably 70 mm to 250 mm, more preferably 100 mm to 200 mm). It is preferable. Thereby, the protection performance of the peripheral part 22 of the windshield 20, the pasting ease of edge sheet 2A, 2B, 2C, and the pasting ease of the center sheet | seat 4 are realizable with sufficient balance. In addition, it is preferable to attach in this way from the viewpoint that the edge sheets 2A, 2B, and 2C are less likely to obstruct the field of view.

  Next, as shown in FIG. 4, the center sheet 4 is attached from above the edge sheet 2 to cover the region including the central portion 24 of the windshield 20. At this time, the peripheral edge portion of the center sheet 4 is overlapped and attached to the inner edge portion of the edge sheet 2. That is, in this overlapping portion, the peripheral edge portion of the center sheet 4 is attached to the back surface of the inner edge portion of the edge sheet 2. Preparation (processing) and pasting of the center sheet 4 are performed so that the overlapping portion of the center sheet 4 and the edge sheet 2 is continuously formed from the right edge sheet 2A through the upper edge sheet 2C to the left edge sheet 2B. Preferably it is done. Thus, it is possible to effectively prevent rainwater from entering from the joint between the edge sheet 2 and the center sheet 4. Therefore, the improvement of workability | operativity by dividing | segmenting the adhesive sheet 1 for glass protection into several sheets, and ensuring of the protection performance of the windshield 20 can be made to make compatible highly.

  Moreover, it can become easy to affix the center sheet | seat 4 appropriately by affixing on the inner edge part of the edge sheet | seat 2, and affixing the peripheral part of the center sheet | seat 4 in this way. This will be described with reference to FIG. FIG. 7 is a cross-sectional view schematically showing a main part of a cross section taken along line VII-VII in FIG. In general, the outer surface 20A of the windshield 20 is a convex curved surface, and the center sheet 4 is placed on the back surfaces of the edge sheets 2A and 2B attached to the peripheral edge 22 along the right side 26A and the left side 26B of the outer end 26, respectively. The center sheet 4 is bent by the thickness of the edge sheets 2A and 2B, compared to the case where the peripheral edge of the center sheet 4 is directly attached to the outer surface 20A of the windshield 20, by overlapping and attaching the peripheral edges of the center sheet 4. can do. That is, the degree to which the shape of the center sheet 4 is deformed from the planar shape can be reduced. Thereby, it may be easy to attach the center sheet 4 appropriately (for example, by reducing the number and degree of wrinkles).

  As shown in FIG. 4, in the portion of the center sheet 4 that is pasted on the right edge sheet 2 </ b> A, there is a protruding portion in which the contour line of the center sheet 4 partially protrudes toward the right side 26 </ b> A of the windshield 20. Is provided. Specifically, the first protrusion 4A1, the second protrusion 4A2, and the third protrusion 4A3 are provided in order from the roof side of the automobile 10 at intervals. Between the first protrusion 4A1 and the second protrusion 4A2 is a first valley 4A6, and between the second protrusion 4A2 and the third protrusion 4A3 is a second valley 4A7. These valley portions 4A6 and 4A7 are portions where the contour line of the center sheet 4 is partially away from the right side 26A of the windshield 20. Providing such troughs 4A6 and 4A7 is effective for facilitating the proper attachment of the center sheet 4 by escaping distortion that may be caused by deforming the center sheet 4 from its planar shape.

  Valley portions 4B6 and 4C6 are also provided in the center portion in the longitudinal direction in the portion of the center sheet 4 that is pasted on the left edge sheet 2B and the portion that is pasted on the upper edge sheet 2C. On both sides of the valley portions 4B6 and 4C6, the contour line of the center sheet 4 is a protruding portion that protrudes toward the outer end 26 of the windshield 20. Furthermore, a trough 4D6 is also provided near the right end of the portion of the center sheet 4 that is pasted along the lower side 26D of the windshield 20. These valleys 4B6, 4C6, 4D6 can also help to escape the distortion of the center sheet 4.

The automobile 10 includes two wipers 80 and 90 configured to be able to wipe the surface of the windshield 20. A wiper (right wiper) 80 for wiping off the right region when the windshield 20 is viewed from the outer surface 20A side is a wiper arm 82 and a blade holding part attached to one end of the wiper arm 82 in the same manner as a known general automobile wiper. 84 and a blade member 86 held by the blade holding portion 84. Similarly, a wiper (left wiper) 90 for wiping the left region when the windshield 20 is viewed from the outer surface 20A side is similarly provided with a wiper arm 92, a blade holding part 94 attached to one end thereof, and a blade holding part 94. And a held blade member 96. The wipers 80 and 90 are driven by a wiper motor (not shown) so as to reciprocate the blade member 86 in the right wiping area WR of the windshield 20 and the blade member 96 in the left wiping area WL. It is configured.
The wipers 80 and 90 move the blade members 86 and 96 along the outer surface of the pressure-sensitive adhesive sheet 1 when the glass-protective pressure-sensitive adhesive sheet 1 is attached to the windshield 20 as shown in FIG. By wiping off deposits (water, dirt, etc.) on the outer surface of the pressure-sensitive adhesive sheet 1, the blade members 86 and 96 are moved along the outer surface 20A of the windshield 20 after the pressure-sensitive adhesive sheet 1 has been removed. It is comprised so that the deposit | attachment of 20A of outer surfaces 20A can be wiped off.

  As shown well in FIG. 8, the center sheet 4 has a blade member 86 at the first protrusion 4A1 at a position WR1 where the blade member 86 of the right wiper 80 is closest to the right side 26A of the windshield 20 (closest position) WR1. And it is affixed so that it may straddle over 2nd protrusion part 4A2. As a result, the blade member 86 at the closest position WR1 is supported on the protrusions 4A1 and 4A2 across the first valley 4A6. Thus, by supporting the blade member 86 on the protrusions 4A1 and 4A2 at the closest position WR1, it is possible to reduce the load that the blade member 86 gives to the right edge seat 2A. By supporting the blade member 86 with the two protrusions 4A1 and 4A2, it is possible to support the blade member 86 more stably than when the blade member 86 is supported by one protrusion (for example, the protrusion 4A2). Moreover, it is preferable also in the point that the force with which the blade member 86 pushes the windshield 20 is disperse | distributed to protrusion part 4A1, 4A2.

In order to make it easy to paste the center sheet 4 so as to have the above positional relationship, a straight line connecting the tips of the first protrusion 4A1 and the second protrusion 4A2 and a parallel line passing through the bottom of the valley 4A6 distance (i.e., the depth of the valley 4A6) _{L D} is suitable to be 20mm or more, preferably to 50mm or more, further preferable to be 70mm or more. By increasing the depth L _D of the valley 4A6, blade member 86 at the closest position WR1 alignment of the center sheet 4 for realizing a state of being supported is facilitated on the protruding portion 4A1, 4A2. Thereby, the work time concerning sticking of the center sheet | seat 4 can be shortened. Increasing the depth L _D of the valley 4A6 is also advantageous from the viewpoint of suppressing wrinkles of the center sheet 4.

On the other hand, when the depth L _D valley 4A6 is too large, the width of the right edge sheet 2A necessary to paste the entire protrusion 4A1,4A2 on the right edge the sheet 2A is increased, the right edge sheet 2A There is a possibility that the ease of sticking tends to decrease. From this point of view, the depth _{L D} of the valley 4A6 is suitable to be less 200 mm, it is preferable to 150mm or less.

Further, from the viewpoint that facilitates performing overall alignment of the center sheet 4 to be affixed on the right edge sheet 2A of the protrusion 4A1, 4A2, depth L _D of the valley 4A6, the protruding portions 4A1 , 4A2 is suitably set to 10% to 90% of the width of the right edge sheet 2A, preferably 20% to 80%, and more preferably 30% to 70%.

  As shown in FIG. 4, the center sheet 4 is such that at least a part of the blade members 86, 96 is always positioned on the center sheet 4 while the blade members 86, 96 reciprocate in the wiping areas WR, WL. Is pasted. As a result, it is possible to prevent an event that the blade members 86 and 96 that have moved to a position disengaged from the center sheet 4 are caught on the outer edge of the center sheet 4 when returning (climbing) onto the center sheet 4 again. Thereby, durability (performance which maintains a favorable affixed state) of pressure-sensitive adhesive sheet 1 for protecting glass against the operation of wipers 80 and 90 can be improved. More preferably, at least 50% or more of the length of the blade members 86 and 96 is always located on the center sheet 4.

  In order to increase the durability of the glass protective pressure-sensitive adhesive sheet 1 with respect to the operation of the wipers 80 and 90, it is also advantageous that the peripheral edge of the center sheet 4 is laminated and adhered to the inner edge of the edge sheet 2. Accordingly, it is possible to prevent the blade members 86 and 96 from being caught on the inner end of the edge sheet 2 when the wipers 80 and 90 are operated.

The valley 4D6 is provided outside the range of the wiping area WR. Thereby, the ease of sticking of the center sheet | seat 4 can be improved, preventing the blade member 86 from contacting the outer surface 20A of the windshield 20 directly.
The adhesive sheet 1 for glass protection of this embodiment is affixed so that the whole range of wiping area | regions WR and WL may be covered. That is, there is no portion where the outer surface 20A of the windshield 20 is exposed in the wiping regions WR and WL. Thereby, it is possible to reliably prevent the blade member 86 from coming into direct contact with the outer surface 20A of the windshield 20, and to exhibit high protection performance.

  In the upper left part of the center sheet 4, there is provided a part (projecting part) 4 </ b> E where the center sheet 4 projects greatly outside the range of the wiping area WL of the blade member 96. By providing such an overhanging portion 4E, if wrinkles are likely to occur when the center sheet 4 is pasted due to immaturity or inadequateness of the operator, the wrinkles are overhanged if the extent is slight. By forming it close to the portion 4E, it is possible to avoid the occurrence of wrinkles in other places. Since the overhang | projection part 4E has remove | deviated from the wiping area | regions WR and WL, even if a wrinkle exists in this location, the blade members 86 and 96 are not caught. Therefore, if wrinkles are likely to occur, by forming wrinkles in the overhanging portion 4E instead of in the wiping areas WR and WL, the work time can be shortened by avoiding reattachment of the center sheet 4, And the influence on the durability of the adhesive sheet 1 for glass protection with respect to operation | movement of the wipers 80 and 90 can be suppressed.

  As a modification of the present embodiment, the upper edge sheet 2C may be attached first, and then the right edge sheet 2A and the left edge sheet 2B may be attached. At this time, the upper ends of the right edge sheet 2A and the left edge sheet 2B may be attached to the back surfaces of both ends of the upper edge sheet 2C so as to overlap. Alternatively, the right edge sheet 2A, the upper edge sheet 2C, and the left edge sheet 2B may be attached in this order, or the left edge sheet 2B, the upper edge sheet 2C, and the right edge sheet 2A may be attached in this order.

  As a modification of the present embodiment, when the edge sheet 2 and the center sheet 4 are each attached in the form of an adhesive sheet with an auxiliary sheet, the auxiliary sheet is peeled off from the back surface of the edge sheet 2 after the edge sheet 2 is attached. After that, the center sheet 4 is preferably pasted on the back surface.

(Second Embodiment)
FIG. 9 is a plan view showing the windshield 20 to which the glass protective adhesive sheet 30 disclosed herein is attached. The windshield 20 is a windshield for an automobile provided with a wiper having a different operation mode from the first embodiment. Specifically, in the wipers 80 and 90 of the first embodiment shown in FIG. 4, the blade members 86 and 96 move in the same direction (here, the right direction) from the lower ends WR0 and WL0 of the wiping areas WR and WL. In the wiper applied to the windshield 20 of the second embodiment shown in FIG. 9, the two blade members are directed from the lower ends WR0, WR0 of the wiping areas WR, WL toward the right side 26A and the left side 26B of the windshield 20, respectively. The two blade members open to the left and right.

  The glass protective adhesive sheet 30 that is attached to the windshield 20 to which such a wiper is applied includes an edge sheet 32 that is attached to the peripheral edge 22 of the windshield 20 and an edge sheet 32 that is attached to the front glass 20 from the front. It is composed of a single center sheet 34 that covers the central portion 24 of the glass 20. The edge sheet 32 includes three adhesive sheets, a right edge sheet 32A, a left edge sheet 32B, and an upper edge sheet 32C, similarly to the edge sheet 2 of the first embodiment. The shape and the pasting position of each edge sheet 32A, 32B, 32C are respectively the same as the edge sheets 2A, 2B, 2C in the first embodiment.

  As in the corresponding portion of the center sheet 4 of the first embodiment, the first projecting portion 34A1, the second projecting portion 34A2, and the third projecting portion 34A3 are attached to the portion of the center sheet 34 that is pasted on the right edge sheet 32A. Are spaced apart from each other. A first valley 34A6 is formed between the first protrusion 34A1 and the second protrusion 34A2, and a second valley 34A7 is formed between the second protrusion 34A2 and the third protrusion 34A3. The relationship between the blade member and the protrusions 34A1 and 34A2 at the position (closest position) WR1 at which the blade member of the right wiper is closest to the right side 26A of the windshield 20 is the same as in the first embodiment.

  In the center sheet 34 of the present embodiment, the portion that is pasted on the left edge sheet 32B is symmetrical to the portion that is pasted on the right edge sheet 32A. In other words, the first protrusion 34B1, the second protrusion 34B2, and the third protrusion 34B3 are spaced apart from each other on the portion of the center sheet 34 that is pasted on the left edge sheet 32B in order from the roof side of the automobile. Is provided. A first valley 34B6 is formed between the first protrusion 34B1 and the second protrusion 34B2, and a second valley 34B7 is formed between the second protrusion 34B2 and the third protrusion 34B3. The center sheet 34 supports the blade member of the left wiper on the protrusions 34B1 and 34B2 across the first valley 34B6 at a position WL1 where the blade member of the left wiper is closest to the left side 26B of the windshield 20 (closest position) WL1. To be pasted. In the center sheet 34, the closest position WR1 of the blade member and the protrusions 34A1 and 34A2 satisfy the above-described positional relationship, and the closest position WL1 of the blade member and the protrusions 34B1 and 34B2 can satisfy the above-described positional relationship. It is formed into a shape.

  By sticking the glass protective pressure-sensitive adhesive sheet 30 having such a shape so as to satisfy the above positional relationship, the blade member of the right wiper is stably supported on the protrusions 34A1, 34A2 at the closest position WR1, In addition, the blade member of the left wiper can be stably supported on the protrusions 34B1 and 34B2 at the closest position WL1. Thereby, the load which these two blade members give to the adhesive sheet 30 for glass protection can be reduced.

  As with the center sheet 4 of the first embodiment, the center sheet 34 is affixed so that at least a part of each blade member is always located on the center sheet 34 in the wiping areas WR and WL. Thereby, durability of the adhesive sheet 30 for glass protection with respect to operation of a wiper can be improved.

  A trough 34C6 is provided at the center in the longitudinal direction of the portion of the center sheet 34 that is pasted on the upper edge sheet 32C, as with the center sheet 4 of the first embodiment. Further, a portion of the center sheet 34 that is pasted along the lower side 26D of the windshield 20 is provided with a trough 34D6 similar to the center sheet 4 of the first embodiment near the right end thereof, and also in the vicinity of the left end. A trough 34D7 having a position and shape symmetrical to the trough 34D6 is provided. These troughs 34C6, 34D6, and 34D7 can be useful for preventing distortion of the center sheet 34 and suppressing the occurrence of wrinkles.

(Third embodiment)
FIG. 10 is a plan view showing a rear glass 320 to which the glass protective adhesive sheet 40 disclosed herein is attached. The rear glass 320 is a rear glass for automobiles to which one wiper (rear wiper) is applied. The wiper is configured to reciprocate the blade member within a semicircular wiping area WC.

  The glass protective adhesive sheet 40 includes an edge sheet 42 attached to the peripheral edge 322 of the rear glass 320, and a single center sheet 44 that is attached from above the edge sheet 42 and covers the central part 324 of the rear glass 320. Has been. The edge sheet 42 is composed of three adhesive sheets, a right edge sheet 42A, a left edge sheet 42B, and an upper edge sheet 42C, as in the edge sheet 2 of the first embodiment. The shape and the pasting position of each edge sheet 42A, 42B, 42C can be the same as the edge sheets 2A, 2B, 2C in the first embodiment except that the pasting target is rear glass.

  A portion of the center sheet 44 that is to be affixed on the left edge sheet 42B and a portion that is to be affixed on the upper edge sheet 42C are respectively provided in the central portion in the longitudinal direction and corresponding portions of the center sheet 4 of the first embodiment. Similar troughs 44B6 and 44C6 are provided. Both sides of the valley portion 44B6 and the valley portion 44C6 are protruding portions in which the contour lines of the center sheet 44 protrude toward the left side 326B and the upper side 326C of the rear glass 320, respectively.

  And in this embodiment, the part affixed on the right edge sheet | seat 42A among the center sheets 44 has a symmetrical shape with the part affixed on the left edge sheet | seat 42B. That is, in the portion of the center sheet 44 that is pasted on the right edge sheet 42A, a trough 44A6 is provided at the center in the longitudinal direction. Both sides of the valley portion 44A6 are protruding portions in which the contour line of the center sheet 44 protrudes toward the right side 326A of the rear glass 320. Providing such troughs 44A6, troughs 44B6, and troughs 44C6 makes it easier to attach the center sheet properly by escaping distortion that may be caused by deforming the center sheet 44 from a planar shape. It is effective for. In the present embodiment, a valley portion is not provided in a portion of the center sheet 44 that is pasted along the lower side 326D of the rear glass 320, but, for example, a valley portion is provided in the central portion in the longitudinal direction of the lower side 326D. Also good.

As with the center sheet 4 of the first embodiment, the center sheet 44 is affixed so that at least a part of the blade member is always positioned on the center sheet 44 in the wiping area WC. Thereby, durability of the adhesive sheet 40 for glass protection with respect to operation of a wiper can be improved.
In addition, the adhesive sheet 40 for glass protection of this embodiment can be preferably applied also to the rear glass of the motor vehicle which does not have a wiper (rear wiper).

  In any of the first to third embodiments described above, the edge sheet is attached to the peripheral portion along the right side, the left side, and the upper side of the window glass, while the edge sheet is not attached to the peripheral portion along the lower side. The peripheral edge of the lower side is configured to be protected by attaching a center sheet, but the usage mode of the glass protective adhesive sheet disclosed herein is in this way along the right side, left side, and upper side of the window glass. It is not limited to the mode of attaching the edge sheet. For example, from the viewpoint of placing more emphasis on protection performance, in addition to attaching an edge sheet to the peripheral portion along the right side, left side, and upper side of the window glass, the edge sheet may also be applied to the peripheral portion along the lower side. Good. Also, from the viewpoint of placing more emphasis on shortening the work time, the edge sheet is pasted only on the peripheral edge along the right side and the left side of the window glass, and the center sheet is pasted on the peripheral edge along the upper side and the lower side of the window glass. It is good also as a structure to protect.

  As a preferred embodiment, as in the first to third embodiments, the edge sheet is affixed to the peripheral portion along the right side, the left side, and the upper side of the window glass, and the edge sheet to be attached to the peripheral portion along the lower side is omitted. The mode to do is mentioned. Of the outer edge of the center sheet, the side facing the lower side of the window glass is less likely to allow rainwater to enter than the side facing the other side (right side, left side and upper side). For this reason, by omitting the edge sheet that is attached to the peripheral edge along the lower side of the window glass, it is possible to effectively shorten the work time related to the application of the adhesive sheet for glass protection while suppressing the deterioration of the protective performance. . Thereby, good protection performance and shortening of working time can be realized at a high level and in a well-balanced manner.

  Moreover, in the said 1st-3rd embodiment, although the adhesive sheet for glass protection in which the trough part was provided in the center sheet was used, the adhesive sheet for glass protection in which the trough part was provided also in the edge sheet was used. Also good. By providing the valley portion in the edge sheet, it is possible to escape distortion that may be caused by causing the edge sheet to conform to the shape of the outer surface of the window glass, and to easily attach the edge sheet appropriately. The location where the valleys are provided in the edge sheet is not particularly limited. For example, a trough can be provided at the inner edge of the edge sheet. In this case, the edge sheet and the center sheet are preferably attached so that the bottom of the valley portion of the edge sheet is covered with the center sheet (that is, the outer surface of the window glass is not exposed).

  The glass protective adhesive sheet (one or both of the edge sheet and the center sheet) disclosed herein may be provided with slits (cuts) directed inward from the outer end of the adhesive sheet. Such slits can help to escape distortion that can be caused by having the adhesive sheet (particularly the center sheet) conform to the shape of the outer surface of the window glass. In addition, from the viewpoint of ease of manufacture of the pressure-sensitive adhesive sheet (such as punchability), it is advantageous not to increase the number of slits excessively. From such a viewpoint, in addition to providing the valleys as described above, it is preferable to provide slits as an auxiliary if necessary. The method for sticking a pressure-sensitive adhesive sheet for protecting glass disclosed herein can be preferably carried out even when a pressure-sensitive adhesive sheet having no slit is used, and the pressure-sensitive adhesive sheet can be appropriately and efficiently applied to the outer surface of an automobile window glass. Can be pasted.

When the pressure-sensitive adhesive sheet for protecting glass disclosed herein is used as the center sheet, the center sheet preferably does not have a portion that bends at an angle of 90 degrees or less on the contour line.
According to the center sheet that does not have a portion (inward corner portion) where the contour line bends inward from the inward at an angle of 90 degrees or less, stress is concentrated on the inward corner portion when the center sheet is handled. It is possible to prevent damages such as general elongation. From such a viewpoint, a center sheet in which the valley is formed by a curve is preferable.
Further, according to the center sheet that does not have a portion (outward corner portion) where the contour line bends inwardly from the outside at an angle of 90 degrees or less, an external force (winder blade member catching, wind pressure) is applied to the outward corner portion. Etc.) can be prevented from being peeled off. From this viewpoint, a center sheet in which the protruding portion is formed by a curve is preferable.

Although not particularly limited, when the glass protective adhesive sheet disclosed herein is used as the edge sheet, the edge sheet has a ratio of the area covered with the edge sheet of the outer surface of the window glass of 10%. It can be preferably used in an embodiment exceeding%. That is, it is preferable that the coverage R _E of the window glass by the edge sheet 10 percent. By increasing the coverage R _E, also to reduce the coverage ratio R _C by the center sheet, it is possible to increase the coverage R _T of the window glass as a whole pressure-sensitive adhesive sheet for glass protection, a sufficient protection performance It can be demonstrated. By reducing the coverage _RC by the center sheet, it can be easy to attach the center sheet appropriately. From this point of view, the coverage R _E of the window glass by the edge sheet is preferably 15% or more, more preferably 20% or more, more preferably 25% or more. On the other hand, from the viewpoint of facilitating the pasting edge sheet suitably is it is advantageous coverage R _E is not too high. For example, it is appropriate to the coverage R _E 60% or less, preferably 50% or less, and more preferably 45% or less.

Here, the covering rate R _E of the window glass by the edge sheet when the edge sheet consists of a plurality of pressure-sensitive adhesive sheet, coverage of the entire their edges sheet refers to a percentage of the area of the window glass . In the first to third embodiments described above, both ends of the upper edge sheet are attached to the right edge sheet and the left edge sheet so that the area of the outer surface of the window glass covered with the edge sheet is the right edge. It becomes smaller than the total value of the individual areas of the sheet, the left edge sheet, and the upper edge sheet. Moreover, in the adhesive sheet sticking method for glass protection disclosed here, since the peripheral part of a center sheet | seat is accumulated and stuck on the inner edge part of an edge sheet, the coverage ratio _RT of the window glass as the whole adhesive sheet for glass protection is set. It is smaller than the sum of the coverage R _C by coverage R _E and center seat according to the edge sheet.

The coverage ratio _RT of the window glass as the entire glass protective adhesive sheet may be 100% or less, and is not particularly limited. From the viewpoint of realizing a good balance between protection performance and ease of application, it is usually preferable that the coverage _RT be 90% or more, and more preferably 95% or more (typically more than 95%). According to the technology disclosed herein, by using a combination of an edge sheet and a center sheet, it is possible to efficiently attach a glass protective adhesive sheet to an automotive window glass with such a high coverage ratio _RT. Can be done well. In addition, it is preferable that the adhesive sheet for glass protection is affixed so that there may be no part which protrudes outside from the outer edge of a window glass from a viewpoint of preventing peeling by wind and invasion of rainwater. That is, it is preferable that it is affixed inside the outer end of the window glass.

  When the edge sheet and the center sheet are used in combination as the glass protective pressure-sensitive adhesive sheet disclosed herein, they can be the same pressure-sensitive adhesive sheet except for the outer shape. According to this aspect, an edge sheet and a center sheet can be prepared by punching out one type of pressure-sensitive adhesive sheet formed in a general-purpose shape as described above. Or you may use the adhesive sheet from which a structure and a structural material mutually differ as an edge sheet | seat and a center sheet | seat. The difference between the edge sheet and the center sheet in this case can be, for example, the composition and thickness of the base material, the composition and thickness of the pressure-sensitive adhesive layer, the formation range of the pressure-sensitive adhesive layer, and the like.

  The matters disclosed by this specification include a glass protective pressure-sensitive adhesive sheet set including any one of the glass protective pressure-sensitive adhesive sheets disclosed herein as a constituent element. As a preferred example of the glass protective pressure-sensitive adhesive sheet, a glass protective pressure-sensitive adhesive sheet, which is a group of a plurality of glass protective pressure-sensitive adhesive sheets used to protect the window glass by being attached to the outer surface of one automotive window glass. Set. Such a glass protective adhesive sheet set is, as the plurality of glass protective adhesive sheets, for example, as in the first to third embodiments described above, one or a plurality of sheets attached to the peripheral edge of the window glass. An edge sheet | seat and one center sheet | seat which covers the center part of the said window glass may be included. According to such a glass protective pressure-sensitive adhesive sheet set, the glass protective pressure-sensitive adhesive sheet contained in the set can be efficiently attached to the outer surface of the automobile window glass to appropriately protect the window glass.

  Several examples relating to the present invention will be described below, but the present invention is not intended to be limited to those shown in the specific examples. In the following description, “parts” and “%” are based on mass unless otherwise specified. Each characteristic in the following description was measured or evaluated as follows.

[Haze measurement]
After peeling off the release liner from the pressure-sensitive adhesive sheet according to each example, using a haze / transmittance meter manufactured by Murakami Color Research Laboratory Co., Ltd., a trade name “HAZEMETER HM-150”, the haze value (in accordance with JIS K7136) %).

[Measurement of heating change rate (HE (60-10))]
The adhesive sheet according to each example was cut into a square shape having a length of 200 mm and a width of 200 mm along with the release liner with the MD direction of the substrate as the vertical direction, and then the release liner was peeled to prepare a measurement sample. The measurement sample was allowed to stand in an environment of 23 ° C. and 50% RH for 1 hour, and then marked lines were formed with an interval of about 150 mm in the MD direction.
After holding the measurement sample in a drying oven at 60 ° C. for 1 hour, the length between the marked lines was measured to the first decimal place with a caliper in an environment at 60 ° C.
Next, after holding the sample in an environment of 10 ° C. for 1 hour, the length between the marked lines was measured to the first decimal place with a caliper in an environment of 10 ° C.
When the length between the marked lines measured in an environment of 60 ° C. is L ₆₀ and the length between the marked lines measured in an environment of 10 ° C. is L ₁₀ , the heating change rate ( HE (60-10)) was calculated.
Rate of change in heating (HE (60-10)) (%) = | (L ₆₀ −L ₁₀ ) / L ₆₀ | × 100

[5% modulus measurement]
The adhesive sheet according to each example was cut into a strip shape having a width of 20 mm and a length of 130 mm together with the release liner with the MD direction of the substrate as the length direction, and then the release liner was removed to prepare a measurement sample. This measurement sample was set on a precision universal testing machine Autograph AG-IS (manufactured by Shimadzu Corporation), and subjected to a tensile test at room temperature (23 ° C.) under conditions of a tensile speed of 300 mm / min and a distance between chucks of 50 mm. -A strain curve was determined. The stress value at the time of 5% elongation of the measurement sample having a width of 20 mm was set to 5% modulus at 23 ° C.

[Tensile modulus measurement]
The adhesive sheet according to each example was cut into a rectangular shape having a width of 25 mm and a length of 50 mm together with the release liner with the MD direction of the substrate as the length direction, and then the release liner was removed to prepare a measurement sample. Based on JIS K7127, the measurement sample was stretched at room temperature (23 ° C.) with a precision universal testing machine Autograph AG-IS (manufactured by Shimadzu Corporation) at a tensile speed of 300 mm / min, and the maximum inclination was measured. . The measured value was obtained by converting into a value per cross-sectional area of the base material based on the thickness value obtained by subtracting the thickness of the pressure-sensitive adhesive from the actual measurement value of the thickness of the pressure-sensitive adhesive sheet. The measurement was performed twice, and the average value was taken as the value of the tensile modulus.

[Measurement of adhesive layer thickness]
The release liner is peeled off from the pressure-sensitive adhesive sheet according to each example, and the total thickness of the pressure-sensitive adhesive sheet (total thickness of the pressure-sensitive adhesive layer and the base material) is measured using a 1/10000 dial gauge, and the arithmetic average thereof is measured. The value was determined. Next, the surface of the base material was exposed by swelling the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet with toluene and scraping it off the base material. The thickness of the exposed base material was measured at 5 points using a 1/10000 dial gauge, and the arithmetic average value thereof was obtained. The difference between the average value of the total thickness of the pressure-sensitive adhesive sheet and the average value of the thickness of the base material was defined as the thickness (average thickness) of the pressure-sensitive adhesive layer.

[Arithmetic mean roughness (Ra) measurement]
The surface roughness (arithmetic average roughness (Ra)) of the adherend pasting surface of the pressure-sensitive adhesive layer was measured as follows. That is, the pressure-sensitive adhesive layer (fixing pressure-sensitive adhesive layer) for fixing the measurement sample is formed on the surface of the slide glass (manufactured by Matsunami Glass Industry Co., Ltd., trade name “White edge polishing No. 2, S-1112”). did. The thickness of this fixing pressure-sensitive adhesive layer was 25 ± 3 μm. Next, the back surface of the base material of the pressure-sensitive adhesive sheet to be measured (including a release liner disposed on the adherend-adhered surface) is bonded to the fixing pressure-sensitive adhesive layer, the release liner is removed, and the measurement target surface ( The adherend pasting surface) was exposed. Further, a non-contact three-dimensional surface shape measuring device manufactured by Veeco, model “Wyko NT-3300” (VSI method. Objective lens 2.5 times, internal lens 0.55 times, Backscan: 10 μm, Length: 15 μm, threshold: The arithmetic average roughness (Ra) (average value of MD and TD) was measured within a range of 5 mm × 5 mm using 1%, Window Filtering: None. The measurement was performed at n = 5, and an average value of three data excluding the upper limit value and the lower limit value was obtained.

[Attachability test]
The pressure-sensitive adhesive sheet according to each example was cut into a strip having a width of 300 mm together with the release liner, with the MD direction of the substrate as the length direction. The belt-like pressure-sensitive adhesive sheet was affixed to a windshield of a model name “Leaf” (2010 model) manufactured by Nissan Motor Co., Ltd. The length of the pressure-sensitive adhesive sheet and the attachment position are such that the top side of the pressure-sensitive adhesive sheet is parallel to the center line at a distance of 10 mm below the center line in the height direction of the windshield, and both ends in the longitudinal direction of the pressure-sensitive adhesive sheet are Each of the windshields was adjusted to have a distance of 10 mm inward from the right side and the left side.
As a specific pasting operation, ion exchange water is applied to the surface of the windshield in advance, the release liner is peeled off from the pressure-sensitive adhesive sheet to expose the pressure-sensitive adhesive layer, and one end in the longitudinal direction of the pressure-sensitive adhesive sheet is It was bonded and positioned in the vicinity of the left side of the windshield in a state wetted with replacement water. Next, a squeegee is applied to the back of the adhesive sheet, and while sliding the squeegee, the adhesive sheet is pressed against the glass while following the surface shape of the windshield, and the entire adhesive sheet is pushed out by extruding air and water. Affixed to the glass surface. At this time, the work time from the positioning to the completion of the adhesive sheet sticking was limited to 10 minutes. Then, the presence or absence and the degree (number and length) of wrinkles in the attached pressure-sensitive adhesive sheet were visually observed, and the pastability was evaluated in the following two stages.
○ (Good): No wrinkles, or wrinkles are 3 or less, and the length of each wrinkle is less than 50 mm.
X (Bad): Four or more wrinkles with a length of less than 50 mm occurred, or one or more wrinkles with a length of 50 mm or more occurred.

[Drainage test]
The adhesive sheet according to each example was cut into a strip shape having a width of 25 mm together with the release liner with the MD direction of the base material as the length direction, and then the release liner was peeled off to prepare a measurement sample. Ion exchange water was dropped on the surface of a glass plate having a length of 120 mm, a width of 70 mm, and a thickness of 5 mm, with a dropper at intervals of 10 mm at five locations on the horizontal center line of the glass plate. The measurement sample was stuck on the ion-exchanged water droplets by reciprocating a 2 kg roller once. Turn over the glass plate to which the measurement sample has been attached, visually observe the adhesive surface of the measurement sample through the glass plate, and (a) the adhesive layer is in close contact with the glass plate, the adhesive layer, From the viewpoint of whether a boundary with the portion where water remains between the glass plate and (b) distortion due to water remaining between the adhesive layer and the glass plate is recognized. The degree of omission was observed. From the results, water drainage was evaluated in the following three stages.
○ (good): Neither of the above (a) and (b) is clearly recognized.
Δ (possible): The above (a) is clearly recognized, and the above (b) is slightly recognized.
X (Bad): Both (a) and (b) are clearly recognized.

[Heating float test]
The adhesive sheet according to each example was cut into a rectangular shape having a length of 100 mm and a width of 50 mm along with the release liner, with the MD direction of the substrate as the vertical direction, and then the release liner was removed to prepare a measurement sample. The measurement sample was bonded to a glass plate having a length of 120 mm, a width of 70 mm, and a thickness of 5 mm with a hand roller in an environment of 23 ° C. and 50% RH. The measurement sample bonded to the glass plate was allowed to stand in an environment of 50 ° C. for 24 hours and then returned again to an environment of 23 ° C. and 50% RH to examine the degree of heating floating. Specifically, whether or not the measurement sample was lifted from the glass plate was visually observed, and when the lift was recognized, the length was measured. When multiple floats were observed, the longest float length among them was measured. From the results, the degree of heating floating was evaluated in the following two stages.
○ (Good): No floating is observed or floating is observed, but the length of the floating is less than 10 mm.
X (defect): The float is recognized and the length of the float is 10 mm or more.

[Weight average molecular weight (Mw)]
The weight average molecular weight Mw was measured under the following conditions using a GPC measuring device manufactured by Tosoh Corporation and a trade name “HLC-8120GPC”, and calculated as a standard polystyrene equivalent value.
[GPC measurement conditions]
Sample concentration: about 2.0 g / L (tetrahydrofuran solution)
Sample injection volume: 20 μL
Column: Trade name “TSKgel, SuperAWM-H + superAW4000 + superAW2500” (manufactured by Tosoh Corporation)
Column size: 6.0 mmI. D. × 150mm
・ Eluent: Tetrahydrofuran (THF)
・ Flow rate: 0.4mL / min
・ Detector: Differential refractometer (RI)
Column temperature (measurement temperature): 40 ° C

<Example 1>
60 parts of 2-ethylhexyl acrylate (2EHA), 40 parts of ethyl acrylate (EA), 10 parts of methyl methacrylate (MMA) and 5 parts of hydroxyethyl acrylate (HEA) were mixed with 2,2′-azobisiso as a polymerization initiator. Polymerization was performed by a solution polymerization method using butyronitrile (product of Kishida Chemical Co., Ltd.) and toluene as a polymerization solvent to obtain a toluene solution of an acrylic polymer having a weight average molecular weight (Mw) of 40 × 10 ⁴ .
In a toluene solution of the acrylic polymer, 3 parts of an isocyanate crosslinking agent (trade name “Coronate L” manufactured by Nippon Polyurethane Industry Co., Ltd.) with respect to 100 parts of the acrylic polymer, and a final solid content of 20% A pressure sensitive adhesive composition was prepared by adding a sufficient amount of toluene and stirring well.
Random polypropylene (manufactured by Nippon Polypro Co., Ltd., trade name “Wintech WFW4”) was melt kneaded with a film molding machine and extruded from a T die of the molding machine to form a film having a thickness of 50 μm. One surface of this film (base material) was subjected to corona treatment. The pressure-sensitive adhesive composition was directly applied to the corona-treated surface and dried to form a pressure-sensitive adhesive layer having an average thickness of 3 μm. In this way, an adhesive sheet according to this example was obtained.

<Example 2>
Random polypropylene (manufactured by Nippon Polypro Co., Ltd., trade name “Wintech WFA4”) was melt-kneaded with a film molding machine and extruded from a T-die of the molding machine to form a film having a thickness of 60 μm. One surface of this film (base material) was subjected to corona treatment. The same pressure-sensitive adhesive composition as in Example 1 was directly applied to the corona-treated surface and dried to form a pressure-sensitive adhesive layer having an average thickness of 3 μm. In this way, an adhesive sheet according to this example was obtained.

<Example 3>
Low density polyethylene (manufactured by Sumitomo Chemical Co., Ltd., trade name “Sumikasen 235P”) was formed into a film having a thickness of 60 μm by inflation-type extrusion film formation. One surface of this film (base material) was subjected to corona treatment. The same pressure-sensitive adhesive composition as in Example 1 was directly applied to the corona-treated surface and dried to form a pressure-sensitive adhesive layer having an average thickness of 7 μm. In this way, an adhesive sheet according to this example was obtained.

<Example 4>
In this example, a PET film having a thickness of 50 μm (manufactured by Mitsubishi Chemical Co., Ltd., trade name “Diafoil S100”) was used as the substrate. The same pressure-sensitive adhesive composition as in Example 1 was directly applied to one surface of this substrate and dried to form a pressure-sensitive adhesive layer having an average thickness of 3 μm. In this way, an adhesive sheet according to this example was obtained.

<Example 5>
Random polypropylene (manufactured by Nippon Polypro Co., Ltd., trade name “Wintech WFW4”) was melt-kneaded with a film molding machine and extruded from a T-die of the molding machine to form a 120 μm thick film. One surface of this film (base material) was subjected to corona treatment. The same pressure-sensitive adhesive composition as in Example 1 was directly applied to the corona-treated surface and dried to form a pressure-sensitive adhesive layer having an average thickness of 12 μm. In this way, an adhesive sheet according to this example was obtained.

  The pressure-sensitive adhesive sheets obtained in Examples 1 to 5 are each formed in the form of a pressure-sensitive adhesive sheet with a release liner by sticking the release surface of the release liner to the adherend application surface. After aging for 1 hour, it was used for various measurements or evaluations. As the release liner, a 50 μm thick PET film having one surface (release surface) subjected to a release treatment was used.

  As shown in Table 1, the pressure-sensitive adhesive sheets of Examples 1 and 2 satisfying a heating change rate (HE (60-10)) of 2.0% or less and a 5% modulus of 7 to 30 N / 20 mm are within the above working time. It was possible to apply wrinkles while suppressing the generation of wrinkles, and the result of the heating float test was also good. In addition, the pressure-sensitive adhesive sheets of Examples 1 and 2 were excellent in water drainage. Furthermore, since the haze value was low, a good field of view could be secured through the window glass to which the adhesive sheet was attached.

  On the other hand, in the pressure-sensitive adhesive sheet of Example 3 in which the rate of change in heating (HE (60-10)) was too large, lifting with a length of 10 mm or more occurred in the heating floating test. Although not shown in Table 1, the pressure-sensitive adhesive sheet of Example 3 was somewhat difficult in terms of handleability because it was too flexible. Further, the pressure-sensitive adhesive sheets of Examples 4 and 5 having an excessively large 5% modulus were difficult to be applied while suppressing the generation of wrinkles, and could not be appropriately applied within the working time set above. The pressure-sensitive adhesive sheet of Example 5 in which the thickness of the pressure-sensitive adhesive layer exceeds 10 μm has low water drainage properties, and the pressure-sensitive adhesive sheet in Example 3 in which the thickness of the pressure-sensitive adhesive layer exceeds 5 μm also has low water drainage properties.

1,30,40 Glass protective adhesive sheet 2,32,42 Edge sheet 2A Right edge sheet 2B Left edge sheet 2C Upper edge sheet 4,34,44 Center sheet 4A1 1st protrusion 4A2 2nd protrusion 4A3 3rd protrusion 4A6 1st trough 4A7 2nd trough 4B6, 4C6, 4D6 trough 4E overhang 10 automobile 12 window molding 20 windshield (window glass for automobile)
20A outer surface 22 peripheral edge portion 24 central portion 26 outer edge 26A right side 26B left side 26C upper side 26D lower side 6 adhesive sheet 6A adherend pasting surface 6B back surface 62 base material 64 adhesive layer 7 auxiliary sheet 72 auxiliary base material 74 auxiliary adhesive Agent layer 100 Adhesive sheet with auxiliary sheet 200 Adhesive sheet with release liner 8 Release liner 80 Wiper (right wiper)
86 Blade member 90 Wiper (left wiper)
96 Blade member 320 Rear glass (car window glass)

Claims (9)

A glass protective pressure-sensitive adhesive sheet for protecting the window glass by being attached to the outer surface of an automotive window glass,
Including a plastic film as a substrate, and an adhesive layer provided on one surface of the substrate,
The glass protective pressure-sensitive adhesive sheet has the following conditions:
A haze value of 10% or less ;
The pressure-sensitive adhesive layer has a thickness of less than 5 μm;
The rate of change in heating between 60 ° C. and 10 ° C. (HE (60-10)) is 2.0% or less; and the stress at 5% elongation at 23 ° C. is 7-30 N / 20 mm;
Satisfies a protective sheet for protecting glass. The adhesive sheet for glass protection of Claim 1 whose tensile elasticity modulus in 23 degreeC is 400-1800 N / mm < ² >. The pressure-sensitive adhesive sheet for glass protection according to claim 1 or 2, wherein the stress at 5% elongation at 23 ° C is 7 to 15 N / 20 mm .   The adhesive sheet for glass protection as described in any one of Claim 1 to 3 which comprises the adhesive sheet with a release liner which has the release liner laminated | stacked on the adherend adhesion surface of the said adhesive layer so that peeling was possible. . It constitutes an adhesive sheet with an auxiliary sheet having an auxiliary sheet laminated on the other surface of the substrate,
The auxiliary sheet includes an auxiliary base material and an auxiliary pressure-sensitive adhesive layer provided on one surface of the auxiliary base material, and the auxiliary pressure-sensitive adhesive layer is detachably attached to the other surface of the base material. The adhesive sheet for glass protection as described in any one of Claim 1 to 4.   The pressure-sensitive adhesive sheet for glass protection according to any one of claims 1 to 5, wherein the pressure-sensitive adhesive sheet for glass protection is processed into an outer shape that fits inside an outer edge of the outer surface of the automotive window glass.   From one side of the said adhesive sheet for glass protection, two or more protrusion parts from which the outline of this adhesive sheet for glass protection partially protrudes outward are provided at intervals. The adhesive sheet for glass protection as described in any one of 6.   The said adhesive sheet for glass protection is a adhesive sheet for glass protection as described in any one of Claim 1 to 7 which is a center sheet which covers the center part of the said window glass for motor vehicles. A pressure-sensitive adhesive sheet set for protecting glass that is attached to the outer surface of a window glass for automobiles to protect the window glass,
The center sheet according to claim 8,
An adhesive sheet set for protecting glass, comprising an edge sheet processed into an outer shape that can be attached to a peripheral edge along an outer edge of at least one side of the window glass for an automobile.

Images