KR20110106796A - Resin laminated product for bonding a flat board, and laminated flat board - Google Patents

Abstract

As for the resin laminated body 1 for flat plate joining of this invention, in the resin laminated body for joining the joining surfaces of two hard flat plates, one flat board 4 is high on the joining surface 4a side. Resin layer A (2) and the other flat plate 6 which have a step 5 of 3-50 micrometers, and are affixed to the joining surface 4a side of the said one flat plate 4 which has the step 5 It has a resin layer C (3) adhering to the bonding surface 6a side of the said resin layer, The storage elastic modulus in 23 degreeC is higher than the said resin layer A (2), It is characterized by the above-mentioned. According to the present invention, there is provided a resin laminate for flat plate joining and a laminated flat plate which can remove bubbles generated at the time of joining bonding surfaces of a flat plate having a step and suppress generation of bubbles over time. Can provide.

Description

RESIN LAMINATED PRODUCT FOR BONDING A FLAT BOARD, AND LAMINATED FLAT BOARD

The present invention relates to a resin laminate and a laminated flat plate for joining flat plates together. More specifically, in a portable information terminal device such as a cellular phone or a mobile device, the present invention relates to a flat plate bonding laminate and a laminated flat plate that can be used for the inner member of the screen display.

The surface of the information display part of the conventional portable information terminal device has covered the periphery with a bezel cover or the like to conceal the electric circuit inside the device. Recently, in order to reduce the thickness and flat surface design, an additional decorative printing layer is applied to a flat plate serving as a display panel instead of a bezel cover in a frame.

Additive printing is generally printing performed to impart concealment or design. However, a minute step of about 3 to 50 µm provided by performing additional decorative printing causes bubbles to mix when joining the flat panel of the display panel to another flat panel. Therefore, usually, the problem of the bubble at the time of bonding is often solved by using a film which can be bent, rather than flat plates.

On the other hand, there are many commercially available touch panels equipped with resistive film type, capacitive type, electromagnetic induction type or infrared type. Among them, the capacitive type touch panel has two-point detection (multi-touch). ), And is valid for the latest mobile applications. Since the capacitive touch panel detects a change in capacitance of the surface, a uniform electric field is required. Usually, the film method is effective as a countermeasure against thinning, weight reduction, and bubble mixing at the time of bonding, and in order to form a uniform electric field, smooth surfaces such as glass become effective. Therefore, in the capacitive touch panel, the joining of the flat plates is required.

As a method of joining the internal members of a conventional portable information terminal device, Patent Document 1 proposes a double-sided adhesive tape using an adhesive on both sides of a core material made of a polyurethane film.

However, in the double-sided adhesive tape of patent document 1, when joining a flat plate and a film which can be deformable, even if there exists some steps, it can adhere without leaving a bubble. However, in the case of attaching flat plates, that is, in the case of joining of non-deformable surfaces, it is impossible to join while driving out bubbles. Therefore, bubbles were mixed on the attachment surface, and it was difficult to completely follow the step.

In contrast, Patent Document 2 proposes a double-sided adhesive sheet having a pressure-sensitive adhesive layer having a loss tangent of 0.6 to 1.5 in the dynamic viscoelastic spectrum and a storage modulus at 80 ° C. of 1.0 × 10 ⁵ Pa or more.

The double-sided adhesive sheet of patent document 2 can remove the bubble mixed when an surface protection panel is affixed on an image display panel by an oatclave process. Moreover, even if it heat-promotes after that, the said bubble does not revive and a new bubble does not generate | occur | produce.

In addition, Patent Document 3 proposes a shock-resistant film for display comprising a first layer having a tan δ of 0.5 or more at 25 ° C., a second layer having a tan δ of less than 0.5 at 25 ° C., and a third layer having a tan δ of 0.5 or more at 25 ° C. .

Also in the impact-resistant film for display of patent document 3, the bubble which generate | occur | produced at the time of bonding can be removed by a heat press process, and a bubble does not recur over time.

[Prior Art Literature]

[Patent Documents]

[Patent Document 1] Japanese Patent Application Laid-Open No. 06-346032

[Patent Document 2] Japanese Patent Application Laid-Open No. 2008-231358

[Patent Document 1] Japanese Patent Laid-Open No. 2009-300506

However, when the double-sided adhesive sheet of Patent Document 2 or the impact-resistant film for display of Patent Document 3 is attached to a surface having a step instead of a glass panel, it is confirmed by the present inventors that bubbles are generated over time after the oatclave treatment. have.

This invention is made | formed in view of the above, The resin laminated body for flat plate bonding which can remove the bubble which arises at the time of the bonding of the joining surfaces of the flat plate which has a level | step difference, and can suppress generation | occurrence | production of a bubble with time. And it aims at providing the laminated flat plate.

MEANS TO SOLVE THE PROBLEM As a result of earnestly researching in order to solve the said subject, it discovered that the subject can be solved by controlling the storage elastic modulus of the resin laminated body for flat plate joining. That is, this invention provides following (1)-(7).

(1) As for the resin laminated body for flat plate joining in the 1st aspect of this invention, in the resin laminated body for joining the joining surfaces of two hard flat plates, one flat plate has a height of 3-the joining surface side. It has a step of 50 μm, has a resin layer A attached to the bonding surface side of the one flat plate having a step and a resin layer C attached to the bonding surface side of the other flat plate, and the storage modulus at 23 ° C. is The resin layer C is higher than the layer A. It is characterized by the above-mentioned.

(2) The resin laminated body for flat plate bonding as described in said (1) further has a resin layer B between the said resin layer A and the said resin layer C in the said resin laminated body, and it stores at 23 degreeC of each resin layer. It is preferable that the relationship of elasticity modulus is resin layer A <= resin layer B <resin layer C. FIG.

(3) The resin laminate for joining the flat plate according to (1) or (2), wherein the storage modulus at 23 ° C of the resin layer A is 0.0001 MPa or more but less than 0.1 MPa, and at 23 ° C of the resin layer C. The storage modulus of is preferably at least 0.1 MPa but less than 0.3 MPa.

(4) It is preferable that the resin laminated body for flat plate joining in any one of said (1)-(3) is a said board | substrate with the said flat plate and the printed layer provided on it.

(5) The laminated flat plate in the second aspect of the present invention is a laminated flat plate in which two hard flat plates are bonded to each other by using the resin laminated body for flat plate bonding according to any one of the above (1) to (4). WHEREIN: One flat plate has a level | step difference of 3-50 micrometers in height on a joining surface side, The said resin layer A adheres to the joining surface side of the said one flat plate which has a level | step difference, and the said resin layer C of the said other flat plate is It is attached to the joining surface side, It is characterized by the above-mentioned.

(6) It is preferable that the laminated flat plate of (5) be used as a screen display member of a portable information terminal device.

(7) It is preferable that the laminated flat plate as described in said (6) is used as an inner member of a capacitive touch panel.

According to the resin laminated body for flat plate joining in the 1st aspect of this invention, the bubble which arises at the time of the joining of the flat plate which has a level | step difference can be removed, and generation | occurrence | production of a bubble with time can be suppressed.

According to the laminated flat plate in the second aspect of the present invention, since it does not have bubbles, it is suitably used as a screen display member of a portable information terminal device without damaging its appearance, and without affecting the formation of an electric field. It is suitably used as an inner member of the touch panel.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic sectional drawing which shows 1st Example of the resin laminated body for flat plate bonding in 1st aspect of this invention.
Fig. 2 is a schematic sectional view showing a first embodiment of a laminated flat plate in a second aspect of the present invention.
Fig. 3 is a schematic sectional view showing a second embodiment of the resin laminate for joining a flat plate in the first aspect of the present invention.
4 is a schematic sectional view showing a second embodiment of a laminated flat plate in a second aspect of the present invention.

The resin laminated body for joining a flat plate in the 1st aspect of this invention is a resin laminated body for joining the joining surfaces of two hard flat plates together, and one flat board has a height of 3-50 micrometers at the joining surface side. It has a resin layer A attached to the bonding surface side of the said one flat board which has a level | step difference, and a resin layer C attached to the bonding surface side of another flat plate, and the storage elastic modulus at 23 degreeC is resin layer C rather than resin layer A The side is characterized by high.

The resin laminated body for planar plate joining in a 1st aspect of this invention will not have a restriction | limiting in particular if it is for bonding the joining surfaces of two hard planar plates. The resin laminated body for joining the flat plate consists of at least two layers of the resin layer A and the resin layer C having different storage modulus. The storage modulus at 23 ° C. is higher in the resin layer C than in the resin layer A.

Of the two flat plates used for joining, one flat plate has a step of 3 to 50 µm in height on the joining surface side. The other flat plate has substantially no step on the joining surface side.

Since the resin layer A adheres to the joining surface side of the said one flat plate which has a level | step difference among both joining surfaces, and the resin layer C adheres to the joining surface side of the other flat plate, step | step followability is ensured and a bubble does not become a problem.

The resin laminated body for flat plate bonding in 1st aspect of this invention may have resin layer B between two layers of resin layer A and resin layer C from which a storage elastic modulus differs. The resin laminated body for flat plate bonding in the 1st aspect of this invention has a resin layer B between resin layer A and resin layer C in the said resin laminated body, and the relationship of the storage elastic modulus in 23 degreeC of each resin layer It is preferable that it is resin layer A <= resin layer B <resin layer C.

It is preferable that the relationship of the storage elastic modulus of each resin layer exists in inclination relationship. When the resin laminated body for flat plate joining which consists of such a resin layer is used for the joining of the flat plate which has a level | step difference as mentioned above, generation | occurrence | production of a bubble can be suppressed.

Next, the Example of the resin laminated body for flat plate bonding in a 1st aspect of this invention, and the laminated flat plate in a 2nd aspect is demonstrated.

In addition, this form is concretely explained in order to understand the meaning of invention better, and it does not limit this invention unless there is particular specification.

(1) First embodiment

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic sectional drawing which shows 1st Example of the resin laminated body for flat plate bonding in 1st aspect of this invention.

The resin laminated body 1 for planar plate joining of this Example is for joining the joining surface 4a and joining surface 6a of the two hard planar plates 4 and the planar plate 6 together. The resin laminated body 1 for joining the flat plate has a resin layer 2 (resin layer A) and a resin layer 3 (resin layer C), and the resin layer 2 (resin layer A) has a thickness of 3 In the flat plate 4 having the additionally decorated printing layer 5 of ˜50 μm, the resin layer 3 (resin layer C) is attached to the side of the bonding surface 4a having the additionally decorated printing layer 5. Is attached to the bonding surface 6a side of the other flat plate 6. In addition, the storage modulus at 23 ° C. is higher in the resin layer 3 (resin layer C) than in the resin layer 2 (resin layer A).

In Fig. 1, a flat plate having the additionally decorated printed layer 5 as a step is taken as an example, but the flat plate having the step is not limited to this, for example, a resin plane that is formed during molding a three-dimensional design having a step. It may be a flat plate having a plate or an electric circuit pattern on its surface.

This resin laminated body 1 for flat plate joining is particularly suitable for joining members used for screen display of portable information terminal devices such as mobile phones and mobile devices.

The resin laminated body 1 for planar plate joining of this Example uses the resin layer 2 (resin layer A) as a component. Although the material of the said resin layer 2 (resin layer A) is not specifically limited, For example, acrylic resin, rubber resin, silicone resin, fluorine resin, etc. are mentioned. Especially, acrylic resin which is easy to control storage modulus and adhesive force with respect to the flat plate 4 is especially preferable.

Although there is no restriction | limiting in particular as acrylic resin, The (meth) acrylic-acid alkylester of C1-C18 of an acryl group is used as an acryl-type monomer which comprises an acryl-type copolymer. As (meth) acrylic-acid alkylester, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, isopropyl acrylate, isopropyl methacrylate, n-butyl acrylate, n-methacrylate Butyl, isobutyl acrylate, isobutyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, cyclohexyl acrylate, lauryl methacrylate, dimethyl acrylamide, and the like. .

Moreover, you may copolymerize the functional group containing monomer copolymerizable with the acryl-type monomer mentioned above. As a copolymerizable functional group containing monomer, it is a monomer which has functional groups, such as a hydroxyl group, a carboxyl group, an amino group, a substituted amino group, and an epoxy group, in a molecule | numerator, Preferably a hydroxyl group containing unsaturated compound and a carboxyl group containing unsaturated compound are used. More specific examples of such functional group-containing monomers include 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl acrylate, Carboxyl group containing compounds, such as hydroxy group containing acrylates, such as 2-hydroxybutyl methacrylate, acrylic acid, methacrylic acid, and itaconic acid, are mentioned. You may use the said functional group containing monomer individually by 1 type or in combination of 2 or more type.

Moreover, you may copolymerize the vinylic monomer copolymerizable with the acryl-type monomer mentioned above. Styrene, (alpha) -methylstyrene, vinyltoluene, vinyl formate, vinyl acetate, an acrylonitrile, glycidyl acrylate, glycidyl methacrylate etc. are mentioned as a vinylic copolymerizable copolymer.

Moreover, you may mix | blend a suitable additive with an adhesive as needed. As an additive, a crosslinking agent, an tackifier, a pigment, dye, a filler, etc. are mentioned, for example, It is good also as an adhesive composition only with the said polymer, without mixing these.

The storage modulus at 23 ° C. of the resin layer 2 (resin layer A) is preferably 0.0001 or more but less than 0.1 MPa, more preferably 0.001 or more but less than 0.09 MPa. When the storage modulus at 23 ° C. of the resin layer A is 0.0001 MPa or more, there is no fear that the yield may decrease due to the exudation of the pool, and when the storage modulus at 23 ° C. of the resin layer A is less than 0.1 MPa, step difference tracking or flat plate Bonding suitability is good.

The thickness of the resin layer A is preferably selected appropriately with respect to the thickness of the step (additional printing layer 5 described later in the first embodiment), preferably 5 to 200 µm, more preferably 10 to 150 µm. , 15-100 micrometers is especially preferable. When the thickness of the resin layer A is 5 micrometers or more, step | step tracking followability and flat plate | board joining fitness are favorable, and when the thickness of the resin layer A is 200 micrometers or less, there is no possibility that a yield may fall by the exudation of a paste.

The resin laminated body 1 for planar plate joining of this Example uses the resin layer 3 (resin layer C) as a component. Although the material of the said resin layer 3 (resin layer C) is not specifically limited, Acrylic resin, rubber resin, silicone resin, fluorine resin, etc. are mentioned similarly to resin layer 2 (resin layer A), and storage elastic modulus is mentioned. Particularly preferred are acryl-based resins that can easily control the adhesion to the flat plate 6.

Although there is no restriction | limiting in particular as an acryl resin, The acrylic resin etc. which the acryl-type copolymer and additives which were used for A-layer, etc. are mentioned.

The storage modulus at 23 ° C. of the resin layer 3 (resin layer C) is preferably 0.1 MPa or more but less than 0.3 MPa, more preferably 0.15 MPa or more but less than 0.2 MPa. When the storage modulus at 23 ° C. of the resin layer C is 0.1 MPa or more, there is no fear that the yield will decrease due to the exudation of the pool, and when the storage modulus at 23 ° C. of the resin layer C is less than 0.3 MPa, step difference tracking or flat plate Bonding suitability is good.

As for the thickness of the resin layer 3 (resin layer C), 5-200 micrometers is preferable like resin layer 2 (resin layer A), 10-150 micrometers is more preferable, 15-100 micrometers is especially preferable. . In the case where the thickness of the resin layer C is 5 µm or more, step tracking or flat plate bonding suitability is good, and in the case where the thickness of the resin layer C is 200 µm or less, there is no fear that the yield may decrease due to the exudation of the pool.

As described above, the storage modulus of the resin layer 3 (resin layer C) is higher than the storage modulus of the resin layer 2 (resin layer A). By controlling the resin layer 2 (resin layer A) at the storage modulus described above, the generation of bubbles is suppressed by following the bonding surface 4a of the flat plate 4 having the additionally decorated printed layer 5. In addition, by controlling the resin layer 3 (resin layer C) at the above-described storage modulus, bubbles are suppressed from being generated by the stress after joining the bonding surface 6a of the flat plate 6.

Moreover, the resin layer can be provided between the resin layer 2 (resin layer A) and the resin layer 3 (resin layer C) within the range which does not impair the objective of this invention.

15-600 micrometers is preferable and, as for the thickness of the resin laminated body for flat plate bonding in 1st aspect of this invention, 30-250 micrometers is more preferable. When the thickness of the resin laminated body for flat plate joining is 15 micrometers or more, step | step followability and flat plate joining suitability are favorable, and when the thickness of the resin laminated body for flat plate joining is 600 micrometers or less, processability, such as blanking, and resin layer are reduced. Deterioration of the surface state at the time of film formation can be suppressed.

Although the thickness of the resin laminated body for flat plate bonding in a 1st aspect of this invention suits the numerical range mentioned above, it is suitable for the thickness of the step (additional printing layer 5 mentioned later in 1st Example) suitably. It is desirable to choose. It is preferable that it is 5-20 times with respect to the thickness of a level | step, and, as for the thickness of the resin laminated body for flat plate joining, 7-15 times are more preferable. In the case of 5 times or more, the step tracking or flat plate bonding suitability is good, and in the case of 20 times or less, it is possible to suppress the deterioration of workability such as blanking or the deterioration of the surface state during film formation of the resin layer.

The following method is mentioned as a manufacturing method of the resin laminated body 1 for flat plate bonding.

The resin solution such as the acrylic resin described above is applied to the heavy peeling sheet and heated / dried to form the resin layer 2 (resin layer A) on the heavy peeling sheet, and further, the resin layer 2 (resin layer A). ), The peeling surface of a light peeling sheet is laminated, and the adhesive resin sheet without the base material clamped by two peeling sheets is produced. In addition, the resin solution is applied to the light peeling sheet separately, and heated / dried to form the resin layer 3 (resin layer C) on the light peeling sheet. In addition, the planar surface which consists of two resin layers by bonding the resin layer 2 (resin layer A) and the resin layer 3 (resin layer C) exposed by peeling the light peeling sheet of the adhesive resin sheet which does not have the above-mentioned base material The resin laminated body 1 for board joining is obtained.

Examples of the method for applying the resin solution include conventionally known methods such as a bar coating method, a knife coating method, a roll coating method, a blade coating method, a die coating method, a gravure coating method, and a caten coating method.

According to the resin laminated body 1 for flat plate bonding, the resin laminated body 1 for flat plate bonding has a resin layer 2 (resin layer A) and a resin layer 3 (resin layer C) having different storage modulus. Since it is made of, it is possible to remove bubbles generated at the joining surface 4a of the flat plate 4 and the joint surface 6a of the flat plate 6 having the additional decorative printing layer 5, which is a step, It is also possible to suppress the generation of bubbles over time.

Fig. 2 is a schematic sectional view showing a first embodiment of a laminated flat plate in a second aspect of the present invention. In FIG. 2, the same components as those used in the description of FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

In the laminated flat plate 7 of this embodiment, the joining surface 4a of the rigid flat plate 4 and the joining surface 6a of the flat plate 6 are joined, and the flat plate 4 is a joining surface ( Although the additional decorative printing layer 5 is provided as a step on the side of 4a), the resin laminated body 1 which consists of the resin layer 2 (resin layer A) and the resin layer 3 (resin layer C) for joining is used. Therefore, bubbles are not generated and the visibility is good.

This laminated flat plate 7 is particularly suitable for joining members used for screen display of portable information terminal devices such as mobile phones and mobile devices.

The flat plate 4 constituting the laminated flat plate 7 is not particularly limited as long as it is a hard material used in a cellular phone or a mobile device, and may include a glass plate and various plastic plates.

As an example of a plastic board, an acryl board, a polycarbonate board, etc. are mentioned.

The flat plate 4 is preferably used as a surface protection panel.

80-5000 micrometers is preferable, as for the thickness of the flat plate 4, 200-4000 micrometers is more preferable, 400-3000 micrometers is especially preferable.

The flat plate 4 has an additional decorative printed layer 5 on the bonding surface 4a side. There is no particular limitation as a printing method for constituting the additional decorative printing layer 5, and gravure printing, screen printing and the like can be used.

It does not specifically limit as a printing pattern, You may perform the printing of a frame-shaped electrode repellent printing and the design which provided designability.

There is no restriction | limiting in particular as a coating material which comprises the additional decorative printing layer 5, A well-known coating material can be used, For example, an ultraviolet curing ink, an oxidative polymerization ink, etc. can be used.

The thickness of the additional decorative printing layer 5 is 3-50 micrometers, 4-30 micrometers is more preferable, 5-20 micrometers is especially preferable. When the thickness of the additionally printed layer 5 is 3 µm or more, sufficient concealability is obtained. When the thickness of the additionally printed layer 5 is 50 µm or less, the resin laminate of the present invention does not have to be thickened, and the total thickness does not become thick.

The flat plate 6 constituting the laminated flat plate 7 is not particularly limited as long as it is a hard material used in a cellular phone, a mobile device, or the like, and examples thereof include glass plates and various plastic plates.

As an example of a plastic board, an acryl board and a polycarbonate board are mentioned.

Further, the flat plate 6 may be a laminated plate made of a TCA (triacetyl cellulose) film or the like.

The flat plate 6 is not particularly limited in thickness as long as the flat plate 6 has a hard plane, and may be formed by laminating members made of a plurality of flat plates, such as an LCD plate (liquid crystal display plate). In this case, flat plates 4 such as acrylic plates and glass plates protect the LCD plates from impact.

The flat plate 6 is preferably used as a display screen panel.

According to the laminated flat plate 7, when applied to a member constituting the screen display of a portable information terminal device such as a cellular phone or a mobile device, bubbles are not generated after bonding, so that visibility is improved. In addition, when applied to the internal member of the capacitive touch panel, bubbles do not affect the electric field, thereby forming a uniform electric field.

(2) Second Embodiment

Fig. 3 is a schematic sectional view showing a second embodiment of the resin laminate for joining a flat plate in the first aspect of the present invention.

In FIG. 3, the same components as those used in the description of FIGS. 1 and 2 are denoted by the same reference numerals, and description thereof will be omitted.

The resin laminated body 9 for flat plate bonding is applied to the joining of members used for screen display of portable information terminal devices, such as a mobile telephone and a mobile device, similarly to the resin laminated body 1 for flat plate bonding.

The resin laminated body 9 for flat plate bonding of this embodiment is added between the resin layer 2 (resin layer A) and the resin layer 3 (resin layer C) in addition to the structure of the resin laminated body 1 for flat plate bonding. Also has the resin layer 8 (resin layer B). Similar to the resin laminate 1 for flat plate bonding, the storage modulus at 23 ° C. is higher than that of the resin layer 2 (resin layer A), and the resin layer 3 (resin layer C) is higher than 23. The relationship between the storage modulus at ° C is the resin layer 2 (resin layer A) ≤ resin layer 8 (resin layer B) ≤ resin layer 3 (resin layer C).

The resin laminated body 9 for flat plate joining of this Example uses the resin layer 8 (resin layer B) as a component. The material of the resin layer 8 (resin layer B) is not particularly limited, but acrylic resins, rubber resins, and silicone resins are similar to resin layers 2 (resin layer A) and resin layers 3 (resin layer C). And fluorine-based resins, and the like, and acrylic resins with easy control of storage modulus are particularly preferable.

As for the thickness of the resin layer 8 (resin layer B), 5-200 micrometers is preferable like resin layer 2 (resin layer A) and resin layer 3 (resin layer C), and 10-150 micrometers is more preferable. It is preferable and 15-100 micrometers is especially preferable. When the thickness of the resin layer B is 5 micrometers or more, step | step traceability and flat plate joining aptitude are favorable, and when the thickness of the resin layer B is 200 micrometers or less, there is no possibility that a yield may fall by exudation of a paste.

As for the thickness of the resin laminated body in 2nd Example of this invention, 15-600 micrometers is preferable and 30-250 micrometers is more preferable like the resin laminated body 1 for flat plate bonding. When the thickness of the resin laminated body is 15 µm or more, step tracking or flat plate bonding aptitude is good. When the thickness of the resin laminated body is 600 µm or less, the workability such as blanking or the surface state during film formation of the resin layer is good. Deterioration can be suppressed.

The storage modulus at 23 ° C of the resin layer 8 (resin layer B) is not particularly limited as long as it is 0.0001 to 0.3 MPa, but is not less than the storage modulus of the resin layer 2 (resin layer A) and is greater than or equal to the resin layer 3 ( The storage modulus of the resin layer C) should be less than or equal to.

If the storage modulus at 23 ° C. of the resin layer B is 0.0001 MPa or more, there is no fear that the yield will decrease due to the exudation of the pool, and if the storage elastic modulus at 23 ° C. of the resin layer B is 0.3 MPa or less, step difference tracking or flat plate Bonding suitability is good.

Moreover, since the storage elastic modulus of each resin layer is in the said inclination relationship, the bubble which arises when it uses for the joining of the flat plate which has a level | step difference like the resin laminated body 1 for flat plate joining can be removed, and also the bubble with time Can be suppressed.

The following method is mentioned as a manufacturing method of the resin laminated body 9 for flat plate bonding.

The resin solution was applied to the heavy peeling sheet and heated / dried to form a resin layer 2 (resin layer A) on the heavy peeling sheet, and further to the resin layer 2 (resin layer A). A peeling surface is laminated and the adhesive resin sheet without the base material clamped by two peeling sheets is produced. In addition, the resin solution was applied to the light peeling sheet separately, and the resin layer 3 (resin layer C) and the resin layer 8 (resin layer B) were formed on the light peeling sheet by heating / drying. Similarly, it forms in the form of an adhesive resin sheet without a base material. Next, the resin layer 2 (resin layer A) and the resin layer 8 (resin layer B) exposed by peeling the light peeling sheet of the adhesive resin sheet without the base material of the resin layer A were bonded together, and the two-layer resin layer The resin laminated body for joining flat plates which consists of these is obtained. Furthermore, the resin layer 8 (resin layer B) and the resin layer 3 (resin layer C) which were exposed by peeling the light peeling sheet of the resin laminated body for flat plate bonding which consist of said two layers of resin layers, are bonded together, The resin laminated body for flat plate joining which consists of three resin layers is obtained.

According to the resin laminated body 9 for flat plate bonding, in addition to the resin laminated body 1 for flat plate bonding, a resin layer is provided between the resin layer 2 (resin layer A) and the resin layer 3 (resin layer C). By stacking (8) (resin layer B), it has the outstanding impact resistance in addition to the effect of the resin laminated body 1 for flat plate bonding. The impact resistance is obtained by absorbing the stress applied to the flat plate 4 by the resin laminate 9 for flat plate bonding.

4 is a schematic sectional view showing a second embodiment of a laminated flat plate in a second aspect of the present invention. In Fig. 4, the same components as those used for the description of Figs. 1 to 3 are assigned the same reference numerals and the description thereof will be omitted.

In the laminated flat plate 10 of this embodiment, the joining surface 4a of the rigid flat plate 4 and the joining surface 6a of the flat plate 6 are joined, and the flat plate 4 is a joining surface ( Although it has the step-added decorative printing layer 5 at the side of 4a), the resin layer 2 (resin layer A), the resin layer 8 (resin layer B), and the resin layer 3 (resin layer C) are joined to a junction. Since the resin laminated body 9 which consists of these is used, foam | bubble does not produce and visibility is favorable.

The laminated flat plate 10 is particularly suitable for joining members used for screen display of portable information terminal devices such as mobile phones and mobile devices.

According to the laminated flat plate 10, in addition to the effect of the laminated flat plate 7, when applied to the screen display of a portable information terminal device such as a mobile phone or a mobile device, it is possible to prevent cracking of the screen display when impacted. In addition, the shock absorbency is obtained by absorbing the stress applied to the flat plate 4 at the time of impact by the flat laminated plate-bonded resin laminate 9.

As described above, the laminated flat plate in the second aspect of the present invention is preferably used as a member of the screen display of the portable information terminal device.

In recent years, from the viewpoint of thinning the screen display unit of the portable information terminal device and blocking extra light from the end face of the information display unit, an additional decorative printed layer has been implemented in a frame shape on a flat plate serving as a display panel. The minute step provided by the additional decoration printing causes bubbles to mix when the flat plate of the display panel and the other flat plate are joined. Such bubbles are a problem that hurts the beauty.

In the second aspect of the present invention, the laminated flat plate is excellent in step tracking performance. Since the resin laminated body for joining the flat plate of the present invention is used, there is no fear of bubbles occurring in the ‚′ part. Therefore, the defect can be eliminated by using the laminated flat plate for screen display of the portable information terminal device.

Further, the laminated flat plate in the second aspect of the present invention is more preferably used as an inner member of the capacitive touch panel.

Many portable information terminal devices are equipped with touch panels such as resistive film, capacitive, electromagnetic induction, or infrared light, but capacitive touch panels detect a change in capacitance on the surface. Because of this, a uniform electric field is required. In order to form a uniform electric field, smooth surfaces such as glass become effective. Therefore, in a capacitive touch panel, joining of flat plates is calculated | required.

The resin laminated body for joining flat plates in the 2nd aspect of this invention is excellent also in step adhesion property also in joining hard flat plates. Therefore, the laminated flat plate in the 2nd aspect of this invention using the said resin laminated body for flat plate joining can maintain a uniform electric field without affecting an electric field by a bubble.

Therefore, the laminated flat plate can be suitably used for the inner member of the capacitive touch panel.

Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not limited to a following example.

[Example]

(Preparation of Resin Melt 1)

100 parts by mass of an acrylic copolymer (BA / MA / 4HBA = 79/20/1, weight average molecular weight 900,000) consisting of butyl acrylate (BA), methyl acrylate (MA), and 4 hydroxybutyl acrylate (4 HBA) 0.05 parts by mass of an isocyanate-based crosslinking agent (manufactured by Soken Chemical Co., Ltd., product name "TD-75", concentration 75%) was mixed, diluted with methyl ethyl ketone to prepare a resin solution 1 having a non-volatile content concentration of 30%.

(Preparation of Resin Melt 2)

An aluminate crosslinking agent in 100 parts by mass of an acrylic copolymer (BA / EA / AAc = 77: 20: 3, weight average molecular weight 900,000) consisting of butyl acrylate (BA), ethyl acrylate (EA) and acrylic acid (AAc) (Made by Soken Chemical, product name "M-5A", concentration 4.95%) 4 parts by mass were mixed, diluted with methyl ethyl ketone to prepare a resin solution 2 having a nonvolatile content of 30%.

(Preparation of Resin Melt 3)

Isocyanate crosslinking agent (100 parts by mass of an acrylic copolymer (BA / MA / AAc = 77: 20: 3, weight average molecular weight 900,000)) consisting of butyl acrylate (BA), methyl acrylate (MA) and acrylic acid (AAc) 1.75 parts by mass of a Dongyang Ink company, product name "BHS-8515", concentration 37.5%) and 1.75 parts by mass of an aluminate-based crosslinking agent (manufactured by Soken Chemical Co., Ltd., product name "M-5A", concentration 4.95%) Dilution with ketone gave a resin solution 3 having a nonvolatile content of 28%.

(Preparation of Resin Melt 4)

The methyl ethyl ketone dilution liquid of the acrylic adhesive (The product made by Lintec Co., Ltd., product name "PM") was used as the resin solution 4.

(Preparation of Resin Melt 5)

Acrylic copolymer consisting of 2-ethylhexyl acrylate (2EHA), cyclohexyl acrylate (CHA) and 2-hydroxyethyl acrylate (HEA) (2EHA / CHA / HEA = 59.7: 40: 0.3, weight average molecular weight 80 0.5 parts by mass of isocyanate-based crosslinking agent (product of Dongyang Ink, product name "BHS-8515", concentration 37.5%) was mixed with 100 parts by mass, diluted with methyl ethyl ketone to prepare a resin solution 5 having a nonvolatile content of 30%. It was.

(Example 1)

The resin solution 1 was applied to a heavy peeling sheet (manufactured by Lintec, product name "SP-PET3811"), and heated at 120 ° C for 2 minutes to form an A layer having a thickness of 100 µm on the heavy peeling sheet. In addition, a layer of light peeling sheet (manufactured by Lintec Co., Ltd., product name "SP-PET3801") was laminated on the A layer, and a base material-less adhesive resin sheet was prepared in which two sheets were peeled off. In addition, the resin solution 2 was separately applied to the light peeling sheet (manufactured by Lintec, product name "SP-PET3801"), and heated at 120 ° C for 2 minutes to form a C layer having a thickness of 50 µm on the light peeling sheet. Furthermore, the light-peel sheet of the adhesive resin sheet without the above-mentioned base material was peeled off, and the exposed A layer and C layer were bonded together, and the resin laminated body for flat plate bonding of Example 1 which consists of two resin layers was obtained.

(Example 2)

A resin laminate for joining a flat plate of Example 2 was obtained in the same manner as in Example 1 except that the A layer was made of a resin solution 1 having a thickness of 100 μm, and the C layer was made of a resin solution 3 having a thickness of 50 μm. .

(Example 3)

The resin solution 4 was applied to a heavy peeling sheet (manufactured by Lintec, product name "SP-PET3811"), and heated at 120 ° C for 2 minutes to form an A layer having a thickness of 50 µm on the heavy peeling sheet.

Moreover, the peeling surface of the light peeling sheet (The product made by Lintec, a product name "SP-PET3801") was laminated on A-layer, and the adhesive resin sheet without the base material clamped by two peeling sheets was produced.

In addition, the resin solution 1 was separately applied to the light peeling sheet (manufactured by Lintec, product name "SP-PET3801"), and heated at 120 ° C for 2 minutes to form a B layer having a thickness of 50 µm on the light peeling sheet. Subsequently, the light peeling sheet of the adhesive resin sheet without the above-mentioned base material was peeled off, and the exposed A layer and B layer were bonded together, and the resin laminated body for flat plate bonding which consists of two resin layers was obtained.

In addition, the resin solution 2 was separately applied to the light peeling sheet (manufactured by Lintec, product name "SP-PET3801"), and heated at 120 ° C for 2 minutes to form a C layer having a thickness of 50 µm on the light peeling sheet. Subsequently, the light-peel sheet of the resin laminate for joining the flat plate composed of the two-layered resin layer described above is peeled off to bond the exposed B layer and the C layer, and the flat plate joining example of Example 3 includes three resin layers. A resin laminate was obtained.

(Example 4)

The resin laminate for joining the flat plate of Example 4 was obtained in the same manner as in Example 1 except that the A layer was made of a resin solution 1 having a thickness of 100 μm, and the C layer was made of a resin solution 5 having a thickness of 50 μm. .

(Comparative Example 1)

Same as Example 3 except that the A layer consists of a resin solution 1 having a thickness of 50 μm, the B layer consists of a resin solution 2 having a thickness of 50 μm, and the C layer consists of a resin solution 1 having a thickness of 50 μm. The resin laminated body for joining the flat plate of the comparative example 1 was obtained by the method.

(Comparative Example 2)

A resin laminate for joining a flat plate of Comparative Example 2 was obtained in the same manner as in Example 1 except that the A layer was made of a resin solution 2 having a thickness of 50 μm, and the C layer was made of a resin solution 1 having a thickness of 50 μm. .

(Comparative Example 3)

Same as Example 3 except that the A layer consists of a resin solution 2 having a thickness of 50 μm, the B layer consists of a resin solution 2 having a thickness of 50 μm, and the C layer consists of a resin solution 2 having a thickness of 50 μm. The resin laminated body for joining the flat plate of the comparative example 3 was obtained by the method. The resin laminated body for joining the plane plates of the comparative example 3 consists of resin 2 with all three layers substantially the same.

(Comparative Example 4)

A layer is made of a resin solution 4 having a thickness of 50 μm, B layer is made of a resin solution 4 having a thickness of 50 μm, and a layer C is made of a resin solution 4 having a thickness of 50 μm. The resin laminated body for joining the flat plate of the comparative example 4 was obtained by the method. The resin laminated body for joining the plane plates of the comparative example 4 consists of substantially the same resin 4 for all three layers.

The properties of the resin laminates for flat plate bonding of the examples and the comparative examples were measured by the following test methods, and the results are shown in Table 1 below.

(1) thickness measurement

The peeling sheet of the adhesive resin sheet without a base material obtained by the Example and the comparative example was removed, and it measured by the static pressure thickness meter (the product made by Techrox, product name; PG-02) according to JISK7130. In addition, the thickness of each resin layer was measured in the state of the single resin layer before lamination, respectively.

(2) storage modulus

The peeling sheet of the adhesive resin sheet without the base material obtained by the Example and the comparative example was removed, and it superposed | polymerized in multiple sheets, and formed the sheet sample of thickness 2.0mm. The formed sheet sample was cut out into a cylindrical shape having a diameter of 8.0 mm ⅹ 2.0 mm, and a viscoelasticity measuring device (Leo-Matric Scientific Co., Ltd. product, trade name "RDAⅠ") was used, and the measurement frequency was 1 Hz by torsional shearing. The storage modulus at 23 ° C. was measured.

(3) Step adhesion (with or without foaming)

Acrylic resin board (Mitsubishi Rayon Co., Ltd., product name "Acrylic L1 01", length 70mm ⅹ 40mm ⅹ thickness 1.5mm) with UV curable ink (Imperial Ink, product name `` POS-911 墨 '') 70 mm width 40 mm width 5 mm) printing was performed so that application thickness might be set to 10 micrometers and 20 micrometers, UV curing was performed, and the acrylic plate which has the step by printing was produced.

A laminator (Fujipura Co., product name "LPD3214") was used for the resin layer surface obtained by cutting the adhesive resin sheet without the base material obtained in Examples and Comparative Examples into a shape of 40 mm by 70 mm width and by removing the light peeling sheet. The laminate was laminated so as to cover the entire surface of the frame-type printing on the printing surface of the acrylic plate.

After lamination, the heavy peeling sheet was peeled off, and a glass plate (NSG Precision Co., Ltd. product name "Corning Garas Eagle XG", thickness of 1.5mmⅹ 70mmⅹ 70mm) was laminated with the laminator on the surface of the exposed resin layer to prepare a sample for step adhesion evaluation. Produced.

Thereafter, autoclave treatment (50 ° C., 0.5 MPa, 20 minutes) was performed to confirm the presence or absence of bubbles. The presence or absence of bubbles was determined in three steps according to the following criteria.

○: no bubbles at all

(Triangle | delta): One or two bubbles are mixed.

X: Three or more bubbles are mixed.

In addition, it was left to stand in 23 degreeC 50% Rh environment for 7 days, and the presence or absence of the bubble was similarly confirmed.

(4) drawing processability

The adhesive resin sheet without the base material obtained in Examples and Comparative Examples was extracted and processed by a extraction processing apparatus (manufactured by Lintec Co., Ltd., name: LPM300) to a length of 70 mm by 70 mm in width to prevent shape deformation of the resin laminate and leaching of the resin layer. Confirmed. When there was no shape deformation and the leaching of the resin layer, it was determined as x when there was no shape deformation or the leaching of the resin layer.

The test results in each Example and Comparative Example are collectively shown in Table 1.

Resin layer
(Thickness μm) 23 ℃ storage modulus
(MPa) Step adhesion
(With or without foaming) Eruption
Machinability Printing step
10 μm Printing step
20 ㎛ A floor B floor C floor A floor B floor C floor A / C treatment
Immediately after A / C treatment
7 days later Immediately after A / C processing A / C treatment
7 days later Example 1 Resin 1 (100) - Resin 2 (50) 0.079 - 0.170 ○ ○ ○ ○ ○ Example 2 Resin 1 (100) - Resin 3 (50) 0.079 - 0.187 ○ ○ ○ ○ ○ Example 3 Resin 4 (50) Resin 1 (50) Resin 2 (50) 0.034 0.079 0.170 ○ ○ ○ ○ ○ Example 4 Resin 1 (100) - Resin 5 (50) 0.079 - 0.107 ○ ○ ○ ○ ○ Comparative Example 1 Resin 1 (50) Resin 2 (50) Resin 1 (50) 0.079 0.170 0.079 ○ × × × ○ Comparative Example 2 Resin 2 (50) - Resin 1 (100) 0.170 - 0.079 △ × × × ○ Comparative Example 3 Resin 2 (150) - 0.170 - - △ × × × ○ Comparative Example 4 Resin 4 (150) - 0.034 - - ○ ○ ○ △ ×

※ A / C: Autoclave

As shown in Table 1, the resin laminate for joining the flat plate of the present invention obtained in Examples showed good step adhesion property with respect to an acrylic plate having a printing step of 10 μm and 20 μm. On the other hand, in the resin laminated body for flat plate bonding obtained by the comparative example 1 and the storage elastic modulus of A-layer which are not inclined relationship between each layer and the comparative example 2 whose storage elastic modulus is 0.1 MPa or more, step adhesion property was bad. Moreover, in the resin laminated body for flat plate bonding obtained by the comparative example 3 and the comparative example which consists of only one layer, it was inferior in step adhesion property or outgoing processability.

1, 9: Resin laminated body for joining flat plate 2: Resin layer A
3: resin layer C 8: resin layer B
4, 6: flat plate 4a, 6a: joining surface
5: additional decoration printing layer 7, 10: laminated flat plate

Claims (11)

In the resin laminated body for joining the joining surfaces of two hard plane plates,
One flat plate has a step of 3 to 50 µm in height on the joining surface side,
It has a resin layer A adhered to the bonding surface side of the said one flat plate which has a level | step difference, and the resin layer C adhered to the bonding surface side of the other flat plate,
The resin laminated body for flat plate bonding characterized by the above-mentioned resin layer C being higher in storage elastic modulus at 23 degreeC than the said resin layer A. 2. The resin laminate according to claim 1, wherein the resin laminate further has a resin layer B between the resin layer A and the resin layer C, and the relationship of the storage modulus at 23 deg. Resin layer C is a resin laminated body for flat plate bonding. The storage modulus at 23 ° C. of the resin layer A is 0.0001 MPa or more but less than 0.1 MPa, and the storage modulus at 23 ° C. of the resin layer C is 0.1 MPa or more but less than 0.3 MPa. Resin laminate for flat plate bonding. The storage modulus at 23 ° C. of the resin layer A is 0.0001 MPa or more but less than 0.1 MPa, and the storage modulus at 23 ° C. of the resin layer C is 0.1 MPa or more but less than 0.3 MPa. Resin laminate for flat plate bonding. The resin laminate for flat plate bonding according to claim 1, wherein the step is a step by a flat plate and a printed layer provided thereon. The resin laminate for flat plate bonding according to claim 2, wherein the step is a step by a flat plate and a printed layer provided thereon. The resin laminated body for joining to a flat plate according to claim 3, wherein said step is a step by a flat plate and a printed layer provided thereon. The resin laminate for flat plate bonding according to claim 4, wherein the step is a step by a flat plate and a printed layer provided thereon. In the laminated flat plate in which two hard flat plates were bonded using the resin laminated body for flat plate joining in any one of Claims 1-8,
One flat plate has a step of 3 to 50 µm in height on the bonding surface side, and the resin layer A is attached to the bonding surface side of the one flat plate having a step, and the resin layer C is bonded to the bonding surface side of the other flat plate. A laminated flat plate, which is attached. A laminated flat plate according to claim 9, which is used as a screen display of a portable information terminal device. The laminated flat plate according to claim 10, which is used as an inner member of a capacitive touch panel.

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