JP2014117831A - Method for producing laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a laminate that does not generate foams during sealing.SOLUTION: The laminate is produced by sequentially carrying out the following steps (1) to (3). (1) a step to produce a laminate X having an adhesive layer Bon a sheet A; (2) a step to slit both ends in a width direction of the laminate X to form a laminate X'; (3) a step to laminate a sheet C having a width Wwider than a width Wof the laminate X', on the adhesive layer Bsuch that both ends of the sheet C are projecting from both ends of the adhesive layer B.

Description

  The present invention relates to a method for manufacturing a laminate.

  In recent years, solar cells that directly convert sunlight into electric energy have attracted attention and are being developed from the viewpoint of effective use of resources and prevention of environmental pollution. A solar cell usually has an ethylene-vinyl acetate copolymer or polyethylene between a front protective sheet (hereinafter sometimes referred to as a front sheet) and a back protective sheet (hereinafter sometimes referred to as a back sheet) from the light receiving surface side. The solar cell is sealed with a sealing film such as a polypropylene film.

  Such a solar cell is usually manufactured by laminating a front protective sheet, a sealing material, a power generation element, a sealing material, and a back protective sheet in this order, and bonding and integrating them by heating and melting. As a solar cell protective material that is a front surface protection sheet or a back surface protection sheet of a solar cell, it is required to have excellent durability against ultraviolet rays. In addition, rusting of internal conductors and electrodes due to permeation of moisture and the like is required. In order to prevent this, it is extremely important to have excellent moisture resistance. Furthermore, it is desired to develop an excellent protective material that causes little deterioration in moisture resistance under long-term use or high-temperature conditions.

For example, in Patent Document 1, a polyester adhesive is used for a moisture-proof sheet having a water vapor transmission rate of 0.22 [g / m ² / day] using a biaxially stretched polyester film as a base material, and weather resistance is provided on the inorganic vapor deposition surface side. A protective film for solar cells was prepared by laminating a polyester film and a polypropylene film on the back, and the moisture resistance after a 1000 hour test was evaluated at 85 ° C. and 85% humidity, and a proposal for preventing moisture degradation was made. Yes.
Moreover, in the Example of patent document 2, a polyurethane adhesive layer is provided on both sides of a moisture-proof sheet having a water vapor transmission rate of 1 to 2 [g / m ² / day] based on a biaxially stretched polyester film, Laminated weather-resistant polyester films on both sides to produce solar cell protective materials, evaluated barrier performance and interlayer strength after 1000 hours accelerated test at 85 ° C and 85% humidity, and proposed to prevent deterioration of both properties. ing.
In Patent Document 3, a PVF film is bonded to a moisture-proof film having a water vapor transmission rate of 0.5 [g / m ² / day], which is also based on a biaxially stretched polyester film, using a two-component curable polyurethane adhesive. After the combination, the moisture resistance and interlayer strength before and after the pressure cooker test (PCT) (severe environment test by high temperature and pressure, 105 ° C., 92 hours) are evaluated, and the proposal for preventing the deterioration of the characteristics is made.

However, each of the techniques disclosed in Patent Documents 1 to 3 relates to a laminate having a moisture-proof film having a water vapor transmission rate of 0.1 [g / m ² / day] or higher, and has higher moisture resistance. When applied to protective materials for solar cells such as compound power generation element solar cell modules that require high performance, in severe environments that are replaced by accelerated durability tests such as the pressure cooker test (PCT), long-term It was not possible to sufficiently maintain moisture resistance and prevent delamination (delamination) at the edge of the protective material.
The solar cell protective material is excellent in moisture resistance and prevention of delamination, and further desired to maintain the moisture resistance and prevention of delamination over a long period of time. When a film having a high moisture-proof property with a rate of less than 0.1 [g / m ² / day] is used, no specific proposal has been made to enable long-term prevention of moisture-proof and delamination. It was a fact.

JP 2007-150084 A JP 2009-188072 A JP 2009-49252 A

  In order to solve the above-mentioned problems, the applicant of the present application, in Japanese Patent Application No. 2011-290036, in a laminate formed by laminating a fluororesin sheet and a moisture-proof sheet, the width A of the fluororesin sheet and the width B of the moisture-proof sheet We have proposed a wider protection material for solar cells.

The protective material for solar cells of Japanese Patent Application No. 2011-290036 is excellent in moisture resistance and can prevent the occurrence of delamination.
However, like the solar cell protective material of Japanese Patent Application No. 2011-290036, a laminated body in which the width of an arbitrary sheet in the laminated body is wider than the width of other sheets (hereinafter referred to as “laminated body having protrusions”). ) Has a problem that foaming occurs and wrinkles occur when the laminate is sealed in a solar cell or the like using a sealing material.

  The subject of this invention is providing the manufacturing method of the laminated body which has a protrusion part which does not produce foaming in the case of sealing.

  As a result of diligent research conducted by the present inventors to solve the above problems, foaming is caused by a narrow recess formed on the side surface of the laminate due to the difference in width between the adhesive layer of the laminate and the base material of the adhesive layer. I found out that it was caused by the cause and came to solve it.

The present invention relates to the following method for producing a laminate.
[1] A method for producing a laminate, wherein the following steps (1) to (3) are sequentially performed.
(1) Step of producing laminate X having adhesive layer B ₁ on sheet A (2) Step of slitting both ends of laminate X in the width direction to make laminate X ′ (3) Adhesive layer B _{1. A process} of laminating a sheet C having a width W _C wider than the width W _{X ′} of the laminated body X ′ so that both ends of the sheet C protrude from both ends of the adhesive layer B ₁

[2] The method for producing a laminate according to [1], wherein [W _{X ′} ] / [W _C ] is 0.7 to 0.98.
[3] In the step (1), a laminate X having a release sheet ₁ on the adhesive layer B ₁ is prepared, and the sheet C is bonded after the step (2). The manufacturing method of the laminated body as described in [1] or [2] which passes through the process of peeling the release sheet ₁ before.
[4] In the step (1), an adhesive layer B ₁ composition coated on the release sheet ₁ and dried to after formation of the adhesive layer B _1, attaching the sheet A to the adhesive layer B ₁ The manufacturing method of the laminated body as described in [3] which produces the laminated body X by this.
[5] The method for manufacturing a laminate according to any one of [1] to [4], wherein the step (3) is performed using an edge position control device.

[6] In the step (1), as the laminate X, _one having the adhesive layer B ₂ on the surface opposite to the adhesive layer B ₁ of the sheet A is produced. [1] to [5] The manufacturing method of the laminated body in any one.
[7] Between the steps (2) and (3) or after the step (3), on the adhesive layer B ₂ , the width is wider than the width W _{X ′} of the laminate X ′, and a sheet the sheet D having a width W _D than the width W _C and C, both ends of the sheet D undergoes a step of bonding so as to protrude from both ends of the adhesive layer B _2, the laminate according to [6] Production method.
[8] In the step (1), a laminate X having a release sheet ₂ on the adhesive layer B ₂ is prepared, and the sheet D is bonded after the step (2). The manufacturing method of the laminated body as described in [7] which passes through the process of peeling the release sheet ₂ before.
[9] In the step (1), a laminate X, the adhesive layer B ₂ composition onto a release sheet ₂ coated, dried after forming the adhesive layer B _2, the adhesive layer B ₂ The method for producing a laminate according to [8], wherein the laminate A is produced by bonding the sheets A together.

[10] The method for manufacturing a laminate according to any one of [7] to [9], wherein the thickness of the sheet D is 60 μm or more.
[11] The method for producing a laminate according to any one of [1] to [10], wherein the sheet C is a weather-resistant sheet.
[12] The method for manufacturing a laminate according to any one of [1] to [11], wherein the sheet A is a moisture-proof sheet.
[13] The method for manufacturing a laminate according to any one of [1] to [12], wherein the laminate is a laminate for protecting an electronic device.
[14] The method for manufacturing a laminate according to [13], wherein the electronic device is a solar battery.

  According to the method for manufacturing a laminate of the present invention, it is possible to easily manufacture a laminate in which a narrow recess is not formed on the side surface of the laminate having a protruding portion and foaming does not occur during sealing.

The figure which shows one Embodiment of each process of the manufacturing method of the laminated body of this invention. The figure which shows other embodiment of each process of the manufacturing method of the laminated body of this invention. The figure which shows one Embodiment of the process (1) of the manufacturing method of the laminated body of this invention. Sectional drawing which shows an example of the laminated body obtained by the manufacturing method of the conventional laminated body The figure which shows one usage example of the laminated body obtained by the manufacturing method of this invention

The manufacturing method of the laminated body of this invention is related with the manufacturing method of a laminated body which performs the process of the following (1)-(3) in order.
(1) Step of producing laminate X having adhesive layer B ₁ on sheet A (2) Step of slitting both ends of laminate X in the width direction to make laminate X ′ (3) Adhesive layer B _{1. A process} of laminating a sheet C having a width W _C wider than the width W _{X ′} of the laminated body X ′ so that both ends of the sheet C protrude from both ends of the adhesive layer B ₁

<Step (1)>
In step (1), a laminate X having an adhesive layer B ₁ on the sheet A is produced.
As shown in FIG. 1, the laminate X only needs to have an adhesive layer B ₁ (21) on the sheet A (1), and further, on the opposite side of the sheet A (1) as shown in FIG. Another adhesive layer B ₂ (22) may be provided on this surface, or another functional layer (not shown) may be provided.
The slit workability and in step (2), in order to improve the handling property, on the adhesive layer B ₁ and the adhesive layer B ₂ preferably has a release sheet (not shown).
Hereinafter, the adhesive layer B ₁ and the adhesive layer B ₂ may be simply referred to as “adhesive layer”.

The laminate X can be produced by applying an adhesive layer composition on the sheet A and drying it to form an adhesive layer. In addition, when the adhesive layer composition is ionizing radiation curable, it is preferable to irradiate ionizing radiation after drying.
Moreover, an adhesive bond layer can also be formed by transferring the adhesive bond layer formed on another base material to the sheet | seat A. FIG.

Moreover, when the laminated body X has a release sheet, the laminated body X can also be produced by bonding the release sheet after forming the adhesive layer on the sheet A, but on the release sheet. It is preferable that the adhesive layer composition is applied and dried, and if necessary, the adhesive layer is formed by irradiation with ionizing radiation, and then the sheet A is bonded to the adhesive layer.
According to the latter method, when the sheet A is a material having poor heat resistance, a laminate X having an adhesive layer on the sheet A can be easily produced by using a material having excellent heat resistance as the release sheet. This is preferable in terms of points.
In the case where the laminate X is configured to have an adhesive layer (21, 22) on both sides of the sheet A (1), as shown in FIG. 3, two release sheets (51, 52) are prepared, A method of forming the laminate X by forming the adhesive layers (21, 22) on the individual release sheets (51, 52) and bonding them so as to sandwich the sheet A (1) is preferable.

  When the adhesive layer composition is applied on the sheet A or the release sheet and dried to form the adhesive layer, the conveying speed of the sheet A or the release sheet is preferably 5 to 15 m / min. By setting it to 5 m / min or more, production efficiency can be raised, and by setting it to 15 m / min or less, foaming due to residual solvent due to insufficient drying can be prevented.

  Although the thickness of the sheet A varies depending on the use of the laminate, it cannot be generally specified, but is usually about 5 to 300 μm.

<Step (2)>
In the step (2), both ends in the width direction of the stacked body X are slit to form a stacked body X ′.
As shown in FIGS. 1 to 3, at the stage where the step (1) is completed, the adhesive layer is narrower than the width of the sheet A and the release sheet, and a step is generated on the side surface of the laminate X. Yes. This is because when the adhesive layer composition is applied so that the width of the adhesive layer matches the width of the base material, the adhesive layer composition wraps around the back side of the base material, resulting in a manufacturing failure. This is unavoidable for manufacturing reasons.
And if the sheet | seat C is bonded together with a level | step difference in the side surface of a laminated body, as shown in FIG. 4, a narrow recessed part will be formed in the side surface of the laminated body which has a protrusion part. And when this laminated body is vacuum-laminated using a sealing material, air tends to remain in this narrow concave portion, which tends to cause foaming.
On the other hand, by passing through the slit process of step (2) as in the present invention, the side surface of the laminated body X ′ has no step, and even when the sheets C and D are bonded together, the side surface of the laminated body having the protruding portion is narrow. Formation of a recess can be prevented, and foaming during vacuum lamination using a sealing material can be prevented.
In addition, the width | variety in this invention means the TD direction (Transverse Direction).

The position of the slit is preferably a position where all of the materials constituting the laminate X (sheet A, adhesive layer, release sheet) can be slit.
The slit method is not particularly limited and can be performed using a known slitter.

  When the laminated body X has a release sheet, it is preferable to go through a step of peeling the release sheet after the step (2) and before the sheets C and D are bonded together.

<Step (3)>
In step (3), on the adhesive layer B ₁ , the sheet C having a width W _C wider than the width W _{X ′} of the laminated body X ′ is protruded from both ends of the adhesive layer B _1. Paste together.
In the laminate obtained in the step (3), as shown in FIGS. 1 and 2, the sheet C (3) projects from both ends of the adhesive layer B ₁ (21) in the width direction, and has a projecting portion 11. It is a laminate.

  The protrusion is formed for various purposes. For example, as shown in FIG. 5, when the laminated body 10 having the protruding portion is vacuum-laminated on the electronic device 30 using the sealing material 20, the sealing material 20 easily wraps around the end portion and prevents delamination. Easy to do. Examples of the electronic device include display elements such as EL elements and liquid crystal display elements, solar cells, touch panels, and the like.

And 'width W _X of _the' stack X, the ratio of the width W _C of the sheet _{C ([W X '] /} [W C]) is not be generalized because it varies depending on the use of the laminate, the laminate Is used as a laminate for protecting an electronic device such as a solar battery, it is preferable that [W _{X ′} ] / [W _C ] is 0.7 to 0.98.
By making [W _{X ′} ] / [W _C ] 0.98 or less, the above-described delamination can be easily prevented.
[W _{X ′} ] / [W _C ] is more preferably 0.75 to 0.95, and further preferably 0.8 to 0.92.
W _{X ′} is usually about 190 to 1170 mm, and W _C is usually about 200 to 1200 mm.
In addition, it is preferable that the width | variety of the sheet | seat C is equally long in the left-right direction of TD direction with respect to the width | variety of laminated body X '.

  The laminate X ′ and the sheet C can be bonded using a known laminating apparatus or the like. In addition, when laminating, in order to make the width of the sheet C equal to the left and right in the TD direction with respect to the width of the laminate X ′, an EPC (edge position control) device is used to laminate the laminate X ′ during lamination. It is preferable to adjust the position of the width between the sheet C and the sheet C.

  In the step (3), it is preferable that the conveyance speed of the laminate X ′ and the sheet C is 20 to 30 m / min. By setting it to 20 m / min or more, production efficiency can be increased, and by setting it to 30 m / min or less, it is easy to perform width adjustment by an EPC apparatus.

  Although the thickness of the sheet C differs depending on the use of the laminate, it cannot be generally specified, but is usually about 5 to 200 μm.

<Sheet D bonding process>
When the laminate X has the adhesive layer B ₂ , the width W _X of the laminate X ′ is placed on the adhesive layer B ₂ between the steps (2) and (3) or after the step (3). a wider than _', the sheet D having a width W _D than the width W _C of the sheet C, both ends of the sheet D to undergo step of bonding in such a manner as to protrude outside from both ends of the adhesive layer B ₂ Is preferred.
On the adhesive layer B _2, a width wider than the 'width W _X of _the' stack X, by providing a sheet D having a width W _D than the width W _C of the sheet C, the curl of the laminate Can be easily prevented.
In addition, W _D is usually about 195~1195mm.

The thickness of the sheet D is preferably 60 μm or more. By setting the thickness of the sheet D to 60 μm or more, curling of the laminate can be easily prevented. The thickness of the sheet D is more preferably 60 to 300 μm, further preferably 75 to 250 μm, and still more preferably 100 to 200 μm.
The ratio (T _C / T _D ) between the thickness T _C of the sheet _C and the thickness T _D of the sheet D is preferably 0.20 to 0.75 from the viewpoint of easily preventing curling of the laminate.

And 'width W _X of _the' stack X, the ratio of the width W _D of the sheet _{D (W X '/ W D} ) , from the viewpoint of easily preventing curling of the laminate, with from 0.71 to 0.99 Preferably there is.
The ratio (W _D / W _C ) between the width W _D of the sheet _D and the width W _{C of the} sheet C may be 0.7 or more and less than 1.0 from the viewpoint of easily preventing curling of the laminate. preferable.
In addition, it is preferable that the width | variety of the sheet | seat D is equally long right and left of TD direction with respect to the width | variety of laminated body X '.

  Although it does not specifically limit as thickness of the whole laminated body, Preferably it is 60-600 micrometers, More preferably, it is 75-350 micrometers, More preferably, it is 90-300 micrometers.

  The laminate X ′ and the sheet D can be bonded using a known laminating apparatus or the like. In addition, when laminating, in order to make the width of the sheet D equal to the left and right in the TD direction with respect to the width of the laminate X ′, an EPC (edge position control) apparatus is used to laminate the laminate X ′ during lamination. It is preferable to adjust the position of the width between the sheet D and the sheet D.

<Sheets A, C, D>
The sheets A, C, and D can be appropriately selected depending on the use of the laminate. Sheets A, C, and D may be made of the same material, or may be different.

Sheets A, C, and D are preferably resin sheets from the viewpoint of handleability.
Examples of the resin constituting the resin sheet include polyolefins such as homopolymers or copolymers such as ethylene, propylene, and butene; amorphous polyolefins such as cyclic polyolefins; polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and the like. Polyester; Polyamide such as nylon 6, nylon 66, nylon 12, copolymer nylon; ethylene-vinyl acetate copolymer partial hydrolyzate (EVOH), polyimide, polyetherimide, polysulfone, polyethersulfone, polyetheretherketone , Polycarbonate, polyvinyl butyral, polyarylate, fluorine resin, acrylic resin, biodegradable resin, and the like.

The sheets A, C, and D may have arbitrary functions. For example, a weather resistant sheet, a moisture proof sheet, an abrasion resistant sheet, an antiglare sheet, an antistatic sheet, a flame retardant sheet, a light diffusing sheet, a self-cleaning sheet, and the like can be given.
When the laminate is used as a member for protecting an electronic device such as a solar battery, it is preferable to use a weather-resistant sheet and a moisture-proof sheet as the sheet A and the sheet C. In particular, a sheet A is used as the sheet C. It is preferable to use a moisture-proof sheet.

As a weather-resistant sheet | seat, the sheet | seat containing resin excellent in weather resistance, such as a fluorine resin and an acrylic resin, is mentioned. Among these, a sheet containing a fluororesin particularly excellent in weather resistance is preferable.
The thickness of the weather-resistant sheet is usually about 20 to 200 μm.

Examples of the fluororesin include polytetrafluoroethylene (PTFE), 4-fluoroethylene-perchloroalkoxy copolymer (PFA), 4-fluoroethylene-6-fluoropropylene copolymer (FEP), 2-ethylene. Examples include -4-fluoroethylene copolymer (ETFE), poly-3-fluoroethylene chloride (PCTFE), polyvinylidene fluoride (PVDF), and polyvinyl fluoride (PVF). Among these, ETFE and FEP are preferable from the viewpoint of easy long-term durability.
When making it a weather-resistant sheet, it is preferable to contain 80% by mass or more, and more preferably 90% by mass or more, of the resin having excellent weather resistance such as fluorine-based resin in the total resin constituting the sheet.

Examples of the moisture-proof sheet include a sheet formed from a resin having excellent moisture resistance such as vinylidene chloride resin, and a sheet formed with an inorganic layer on a general-purpose plastic film such as a polyester film.
The thickness of the moisture-proof sheet is usually about 5 to 300 μm.

Examples of the inorganic substance constituting the inorganic layer include silicon, aluminum, magnesium, zinc, tin, nickel, titanium, and the like, or oxides, carbides, nitrides, oxycarbides, oxynitrides, oxycarbonitrides, diamond-like substances thereof. Carbon or a mixture thereof may be mentioned, in particular, silicon oxide, silicon nitride, silicon oxycarbide, silicon oxynitride, silicon oxycarbonitride, aluminum oxide, aluminum nitride, aluminum oxycarbide, aluminum oxynitride and mixtures thereof High moisture resistance is preferred in that it can be stably maintained.
The inorganic layer can be formed by coating or vapor deposition, but vapor deposition is preferred because a uniform thin film having high gas barrier properties can be obtained. This vapor deposition method includes methods such as physical vapor deposition (PVD) and chemical vapor deposition (CVD). Examples of physical vapor deposition include vacuum deposition, ion plating, and sputtering. Examples of chemical vapor deposition include plasma CVD using plasma, and a catalyst that thermally decomposes a material gas using a heated catalyst body. Examples include chemical vapor deposition (Cat-CVD).

The inorganic layer may be a single layer or a multilayer. In the case of multiple layers, the same film formation method may be used, or a different film formation method may be used for each layer. From the viewpoint of sex.
In particular, the multilayer structure includes an inorganic layer formed by a vacuum deposition method, an inorganic layer formed by a chemical vapor deposition method, and an inorganic layer formed by a vacuum deposition method in this order. Is preferred.
In addition, when an inorganic layer is a multilayer, each layer may consist of the same inorganic substance, or may consist of a different inorganic substance.

The thickness of the inorganic layer is preferably 10 to 1000 nm, more preferably 40 to 800 nm, and still more preferably 50 to 600 nm, from the viewpoint of stable moisture-proof performance and transparency.
The water vapor transmission rate at 90 ° C. of the moisture-proof sheet is preferably less than 0.1 [g / m ² / day], more preferably 0.05 [g / m ² / day] or less, More preferably, it is 0.03 [g / m ² / day] or less.
The water vapor transmission rate is measured in accordance with various conditions of JIS Z 0222 “moisture-proof packaging container moisture permeability test method” and JIS Z 0208 “moisture-proof packaging material moisture permeability test method (cup method)”.

As described above, the sheet D preferably has a thickness of 60 μm or more.
Moreover, as for the sheet | seat D, the thing whose tensile elasticity modulus measured by the method as described in an Example according to JISK7127 is 2.0 GPa or more is more suitable. The tensile elastic modulus is more preferably 2.0 to 10.0 GPa, and further preferably 2.0 to 8.0 GPa.
By having a tensile elastic modulus in the above range, it is possible to exhibit deformation resistance against deformation of external force, and it is easy to prevent curling of the laminate.

  The sheet D may be added with an inorganic material such as talc or an organic or inorganic material such as a filler to improve the reinforcing effect of the tensile elastic modulus in the material exemplified above as the resin sheet.

When the laminate is used as a laminate for protecting an electronic device such as a solar battery, the use environment may become high. For example, when using a laminated body for the protection sheet for solar cells, a solar cell module raises the use temperature to about 85-90 degreeC by the heat_generation | fever at the time of electric power generation, the radiant heat of sunlight, etc. Since the sheet D is located on the solar cell side, the melting point is preferably 90 ° C. or higher.
Accordingly, as the sheet D, polyethylene naphthalate, polyethylene terephthalate, or the like, or polypropylene (PP), polylactic acid (PLA), polyvinyl fluoride (PVF), polyvinylidene fluoride (PVDF), cellulose butyrate (CAB), etc. What consists of any 1 type or several resin of resin is preferable, and it is preferable that these resins contain 50 mass% or more.

<Adhesive layer>
An adhesive bond layer is used in order to adhere | attach the sheet | seat (sheet | seat A, C, D) which comprises a laminated body.
The material constituting the adhesive layer includes acrylic adhesive, rubber adhesive, polyester adhesive, etc., solution adhesive, hot melt adhesive, thermosetting adhesive, ionizing radiation curable adhesive In addition to adhesives such as adhesives, thermoplastic resin films (so-called sealant films) that can be thermocompression-bonded can be used. Among these, an adhesive is preferable. The thickness of the adhesive layer is about 2 to 25 μm.

Adhesives adhere at the same time by applying a slight pressure at room temperature for a short time, and have both the properties of a liquid (fluidity) for getting wet with the adherend and the property of a solid (cohesive force) that resists peeling. It is also called a pressure sensitive adhesive and is distinguished from a normal adhesive. In addition, normal adhesives such as solution-type adhesives, thermosetting adhesives, and hot-melt adhesives solidify due to chemical reaction, solvent volatilization, temperature changes, etc., whereas adhesives are semi-solid and solidify This process is not necessary, and the state does not change even after the bonding is formed.
The tensile storage modulus of the adhesive layer at 100 ° C., frequency 10 Hz, and strain 0.1% is preferably 5.0 × 10 ^{4 to} 5.0 × 10 ⁵ Pa.
By setting the tensile storage modulus to 5.0 × 10 ⁴ or more, it is possible to prevent the adhesive layer from flowing out during the laminating process and to prevent lamination by setting the tensile storage modulus to 5.0 × 10 ⁵ Pa or less. Stress generated by shrinkage of layers other than the adhesive layer constituting the body can be absorbed by the adhesive layer.

In order to set the tensile storage modulus at 100 ° C., frequency 10 Hz, and strain 0.1% of the adhesive layer in the range of 5.0 × 10 ⁴ to 5.0 × 10 ⁵ Pa, the pressure-sensitive adhesive is an acrylic pressure-sensitive adhesive. It is preferable to include. The acrylic pressure-sensitive adhesive is preferably contained in an amount of 50% by mass or more, more preferably 65% by mass or more, and further preferably 80% by mass or more in the total solid content of the adhesive layer.

As the acrylic pressure-sensitive adhesive, a polymer or copolymer (hereinafter referred to as a main monomer component having a low glass transition point (low Tg), a comonomer component having a high glass transition point (high Tg), and a functional group-containing monomer component) , "Acrylic (co) polymer") is preferred.
Examples of the main monomer component of low Tg include acrylic acid alkyl esters such as ethyl acrylate, butyl acrylate, amyl acrylate, 2-ethylhexyl acrylate, octyl acrylate, cyclohexyl acrylate, and benzyl acrylate, and methacrylic acid. Examples thereof include methacrylic acid alkyl esters such as butyl, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, and benzyl methacrylate. These may be used alone or in combination of two or more.
Examples of the high Tg comonomer component include methyl acrylate, methyl methacrylate, ethyl methacrylate, vinyl acetate, styrene, acrylonitrile and the like. These may be used alone or in combination of two or more.
Examples of the functional group-containing monomer component include carboxyl group-containing monomers such as acrylic acid, methacrylic acid, maleic acid, and itaconic acid, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and N-methylol. Examples include hydroxyl group-containing monomers such as acrylamide, acrylamide, methacrylamide, glycidyl methacrylate, and the like. These may be used alone or in combination of two or more.

Examples of the initiator used for polymerization of the monomer component of the acrylic pressure-sensitive adhesive include azobisisobutylnitrile, benzoyl peroxide, di-t-butyl peroxide, cumene hydroperoxide, and the like. Moreover, there is no restriction | limiting in particular about the copolymerization form of the acrylic (co) polymer used as the main component of an acrylic adhesive, Any of a random, block, and graft copolymer may be sufficient.
Moreover, as a molecular weight in case an acrylic adhesive is the above-mentioned acrylic (co) polymer, what is 300,000-1,500,000 is preferable at a weight average molecular weight, and it is still more preferable that it is 400,000-1 million. . By adjusting the weight average molecular weight within the above range, adhesion to the adherend and adhesion durability can be ensured, so that delamination of the laminate can be further prevented.

In the acrylic (co) polymer, the content of the functional group-containing monomer component unit is preferably in the range of 1 to 25% by mass. By setting the content of the functional group-containing monomer component within the range, adhesion to the adherend and the degree of crosslinking are ensured, and the tensile storage modulus of the adhesive layer is 100 ° C., frequency 10 Hz, strain 0. A value of 5.0 × 10 ^{4 to} 5.0 × 10 ⁵ Pa can be obtained at 1%.

<Release sheet>
As the release sheet, a resin sheet having releasability with respect to the adhesive layer is preferably used.
Examples of the release sheet include those obtained by subjecting the surface of the resin sheet to a release treatment with a silicone release agent or the like, and olefin-based resin sheets, and those having a melting point of 90 ° C. or higher are preferable.
Even if the sheet A is inferior in heat resistance by using a release sheet having a melting point of 90 ° C. or higher, the adhesive layer composition is applied to the release sheet and dried to form an adhesive layer. The laminated body X can be produced by bonding with A.
Examples of the release sheet having a melting point of 90 ° C. or higher include those obtained by subjecting the surface of the resin sheet exemplified as the sheet D to a release treatment with a silicone release agent or the like.

<Others>
In the present invention, when the laminate is a laminate for protecting an electronic device such as a solar cell protective material, after the laminate is produced, the sheet A side or the sheet C side (in the case of having the sheet D, the sheet D) is further provided. The sealing material-integrated protective material can be produced by laminating the sealing material layer on the side) via an adhesive layer as necessary. By using a sealing material integrated protective material in which a sealing material layer is laminated in advance, for example, in the manufacture of solar cell modules, each of the front sheet, sealing material, power generation element, sealing material, and backsheet in the vacuum lamination process is used. The operation | work which laminates | stacks individually can be reduced and efficiency improvement of a solar cell module manufacture can be aimed at.

In the sealing material-integrated protective material, examples of the sealing material constituting the sealing material layer include a silicone resin-based sealing material, an ethylene-vinyl acetate copolymer, and a random copolymer of ethylene and α-olefin. Examples include coalescence. Examples of the α-olefin include propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 3-methyl-butene-1, and 4-methyl. -Pentene-1 etc. are mentioned.
In the sealing material-integrated protective material, the width of the sealing material layer is preferably smaller than the width of the sheet C and larger than the maximum width of the laminate constituting layer other than the sheet C. Thereby, at the time of vacuum lamination, the end surface of the laminated body constituting layer other than the sheet C can be sealed with the sealing material, and the moisture resistance of the laminated body can be prevented from being lowered and delamination can be prevented.

When the laminated body is a laminated body for protecting an electronic device such as a solar cell protective material, the thickness of the laminated sealing material layer is preferably 200 to 750 μm, more preferably from the viewpoint of protecting the solar cell element and the like. Is 300-600 μm.
As the adhesive layer, the same adhesive as the pressure-sensitive adhesive or adhesive constituting the above-mentioned adhesive layer can be used. Especially as this adhesive agent, the thing containing a polyurethane-type adhesive agent is preferable, and the thing which has a polyurethane-type adhesive agent as a main component is more preferable.

  EXAMPLES The present invention will be described more specifically with reference to examples. However, the present invention is not limited by these examples and comparative examples. In addition, the measurement and evaluation of the physical property of a laminated body were performed as follows.

[Foaming]
Laminate glass, encapsulant and each laminate (laminate for solar cell protective material) E-1 to E-7 in order so that sheet A (weather-resistant layer, fluororesin film) is on the exposed side. Using a vacuum laminator (trade name: LM30 × 30, manufactured by NPC Corporation), vacuum at a temperature of 150 ° C., a degassing time of 5 minutes, a press pressure of 0.1 MPa, and a press time of 10 minutes. Lamination was performed, the state was observed, and the following criteria were evaluated.
(○): No bubbles at all (×): One or more bubbles are confirmed

[End face sealed state]
Vacuum lamination was performed under the same conditions as the foaming evaluation, the state was observed, and the following criteria were evaluated.
(◯): The sealing material reaches the end face of the fluororesin film width, and no extreme thinning occurs.
(X): The sealing material does not extend to the end face of the fluororesin film width, or the thickness of the reaching sealing material is small, and the end portion is thinned.

[Delamination test]
Each laminated body (laminated body for solar cell protective material) E-1 to E-7 was vacuum-laminated by the above method, and then, using a pressure cooker test LSK-500 manufactured by Tommy Seiko Co., Ltd., 105 ° C., humidity 100 %, The test time until the occurrence of delamination could be visually confirmed at the end face portion of the solar cell protective material was measured. Those in which the occurrence of delamination could not be confirmed in 90 hours were over 90 hours (> 90).

[Tensile storage modulus of adhesive layer]
On the silicone release PET film, 25 g / m ^{2 of} an adhesive described later was applied. This was cured at 40 ° C. for 4 days, and then maintained at 150 ° C. for 30 minutes to form an adhesive layer. Thereafter, only the adhesive layer is taken out, a predetermined number of sheets are stacked so that the thickness becomes 200 μm, a sample (4 mm long, 60 mm wide, 200 μm thick) is prepared, and the obtained sample is manufactured by IT Measurement Co., Ltd. Using a viscoelasticity measuring device, trade name “Viscoelasticity Spectrometer DVA-200”, vibration frequency 10 Hz, strain 0.1%, heating rate 3 ° C./min, 25 mm between chucks in the lateral direction, from −100 ° C. The stress against strain applied to the sample up to 180 ° C. was measured. From the obtained data, the tensile storage elastic modulus (MPa) at 100 ° C., frequency 10 Hz, and strain 0.1% was determined.

<Constituent materials>
(Sheet A: Moisture-proof sheet)
As a base material, a biaxially stretched polyethylene naphthalate film (made by Teijin DuPont, “Q51C12”) having a thickness of 12 μm is used, and the following coating solution is applied to the corona-treated surface and dried to form an anchor coat having a thickness of 0.1 μm. A layer was formed.
Next, SiO was heated and evaporated under a vacuum of 1.33 × 10 ⁻³ Pa (1 × 10 ⁻⁵ Torr) using a vacuum deposition apparatus, and a 50 nm thick SiO _x (x = 1) was formed on the anchor coat layer. .5) A moisture-proof film having a thin film was obtained and cut into a width of 200 mm for use. The produced moisture-proof film had a water vapor transmission rate of 0.01 [g / m ² / day].

Coating solution 20 g of polyvinyl alcohol resin of the trade name Gohsenol (degree of saponification: 97.0 to 98.8 mol%, degree of polymerization: 2400) manufactured by Nippon Synthetic Chemical Co., Ltd. was added to 2810 g of ion-exchanged water, 645 g of 35 mol% hydrochloric acid was added with stirring at ° C. Subsequently, 3.6 g of butyraldehyde was added with stirring at 10 ° C., and after 5 minutes, 143 g of acetaldehyde was added dropwise with stirring to precipitate resin fine particles. Subsequently, after hold | maintaining at 60 degreeC for 2 hours, the liquid was cooled, neutralized with sodium hydrogencarbonate, washed with water, and dried, and the polyvinyl acetoacetal resin powder (acetalization degree 75 mol%) was obtained.
Further, an isocyanate resin (“Sumidule N-3200” manufactured by Sumitomo Bayer Urethane Co., Ltd.) was used as a cross-linking agent and mixed so that the equivalent ratio of isocyanate groups to hydroxyl groups was 1: 2.

(Sheet C: Weatherproof Sheet (Fluorine Resin Sheet))
As the sheet C, a tetrafluoroethylene / ethylene copolymer (ETFE) film (manufactured by Asahi Glass Co., Ltd., Aflex 50 MW1250 DCS, thickness 50 μm) was used, and a sheet having the following width W _c was prepared.
C-1: W _C 200 mm, C-2: W _C 230 mm, C-3: W _C 190 mm, c-4: W _C 210 mm

(Sheet D)
As the sheet D, a biaxially stretched polyethylene terephthalate sheet (manufactured by Mitsubishi Plastics, T100, width 195 mm, thickness 125 μm, melting point 265 ° C.) was prepared.

(Sheet D)
As the sheet D, a biaxially stretched polyethylene terephthalate sheet (manufactured by Mitsubishi Plastics, T100, width 195 mm, thickness 125 μm, melting point 265 ° C.) was prepared.
The tensile modulus of sheet D measured by the following method was 2.5 GPa.
Tensile modulus of sheet According to JIS K 7127, a sample with a width of 10 mm, a distance between marked lines of 50 mm, and a chuck distance of 25 mm was left in a standard state (23 ° C. × 50 RH%) for 12 hours, and then at a test speed of 50 mm / min. A tensile test was performed to determine the tensile modulus.

(Adhesive)
Using a reactor equipped with a thermometer, a stirrer, a reflux condenser, and a nitrogen gas inlet tube, a mixed solution of 90 parts by mass of butyl acrylate, 10 parts by mass of acrylic acid, 75 parts by mass of ethyl acetate, and 75 parts by mass of toluene, 0.3 parts by mass of azobisisobutyronitrile was added, and polymerization was performed at 80 ° C. for 8 hours in a nitrogen gas atmosphere. After completion of the reaction, the solid content was adjusted to 30% by mass with toluene to obtain a resin having a mass average molecular weight of 500,000. To 100 parts by mass of the obtained resin, 1 part by mass of a product name Coronate L (solid content: 75% by mass) manufactured by Nippon Polyurethane Industry Co., Ltd. was added as an isocyanate-based crosslinking agent to prepare an adhesive. The tensile storage elastic modulus of the adhesive layer (adhesive layer) at 100 ° C., frequency 10 Hz, and strain 0.1% was 3 × 10 ⁵ Pa.

(Adhesive and adhesive coating solution)
HD1013 manufactured by Rock Paint Co., Ltd. is used as the main component containing the polyurethane polyol component, and H62 manufactured by Rock Paint Co., Ltd. is used as the curing agent containing the aliphatic hexamethylene diisocyanate component, resulting in a weight ratio of 10: 1. Were mixed with each other and diluted with ethyl acetate so that the solid content concentration was 30% by mass to prepare an adhesive coating solution.

(Encapsulant)
Brand name: EVASKY S11 (thickness 500 μm, melting point 69.6 ° C.) manufactured by Bridgestone Corporation, ethylene-vinyl acetate sealing material was used.

(Glass)
A cover glass TCB09331 (3.2 mm thickness) manufactured by AGC Fabritech Co., Ltd. was used and cut into glass of the same size as the fluororesin film used in each of the examples and comparative examples.

Example 1
A pressure-sensitive adhesive was applied to a thickness of 20 μm on a 38 μm-thick silicone release PET film (manufactured by Nakamoto Pax, NS-38 + A, melting point 262 ° C., width 200 mm), and dried to form a pressure-sensitive adhesive layer. A sheet was produced. A pressure-sensitive adhesive sheet was bonded to one surface of the moisture-proof film to obtain a laminate X.
Subsequently, both ends in the width direction of the laminate X were slit by 5 mm to obtain a laminate X ′ (width W _{X ′} : 190 mm).
Next, the release sheet of the laminate X ′ is peeled off, and the fluororesin sheet C-1 is bonded and cured at 40 ° C. for 4 days. The fluororesin sheet (C-1) -adhesive layer (adhesive) Layer) —a laminate (protective material for solar cell) E-1 having a structure of a moisture-proof sheet (sheet A) was obtained.

Example 2
A pressure-sensitive adhesive was applied to a thickness of 20 μm on a 38 μm-thick silicone release PET film (manufactured by Nakamoto Pax, NS-38 + A, melting point 262 ° C., width 200 mm), and dried to form a pressure-sensitive adhesive layer. A sheet was produced. An adhesive sheet was bonded to both surfaces of the moisture-proof film to obtain a laminate X.
Subsequently, both ends in the width direction of the laminate X were slit by 5 mm to obtain a laminate X ′ (width W _{X ′} : 190 mm).
Next, the release sheet of the laminate X ′ is peeled off, the fluororesin sheet C-1 is bonded to one pressure-sensitive adhesive layer, the sheet D is bonded to the other pressure-sensitive adhesive layer, and cured at 40 ° C. for 4 days. And a laminated body (for solar cell) having a configuration of a fluorine-based resin sheet (C-1) -adhesive layer (adhesive layer) layer-moisture-proof sheet (sheet A) -adhesive layer (adhesive layer) -sheet D Protective material) E-2 was obtained.

Example 3
A laminate of Example 3 was obtained in the same manner as in Example 1 except that the pressure-sensitive adhesive layer was changed to an adhesive layer (thickness 7 μm) formed from the above-described adhesive coating solution. In addition, the laminated body (protective material for solar cells) of Example 3 is set to E-3.

Example 4
A laminate of Example 4 was obtained in the same manner as Example 2 except that the pressure-sensitive adhesive layer was changed to an adhesive layer (thickness 7 μm) formed from the above-mentioned adhesive coating solution. In addition, the laminated body (protective material for solar cells) of Example 4 is set to E-4.

Example 5
A laminate of Example 4 was obtained in the same manner as Example 1 except that the fluorine resin sheet C-1 was changed to the fluorine resin sheet C-2. In addition, let the laminated body (protective material for solar cells) of Example 5 be E-5.

Comparative Example 1
A pressure-sensitive adhesive was applied to a thickness of 20 μm on a 38 μm-thick silicone release PET film (manufactured by Nakamoto Pax, NS-38 + A, melting point 262 ° C., width 200 mm), and dried to form a pressure-sensitive adhesive layer. A sheet was produced. A pressure-sensitive adhesive sheet was bonded to one surface of the moisture-proof film to obtain a laminate X.
Next, the release sheet of the laminate X is peeled off, and a fluorine-based resin film C-4 is bonded to each other, and the structure is composed of a fluorine-based resin sheet (C-4) -adhesive layer (adhesive layer) -a moisture-proof film. A laminate (protective material for solar cell) E-6 was obtained.

Comparative Example 2
The laminated body of the comparative example 2 was obtained like Example 1 except having changed the fluorine resin sheet C-1 into the fluorine resin sheet C-3. In addition, the laminated body (protective material for solar cells) of the comparative example 2 is set to E-7.

As is clear from the results in Table 1, the laminates of Examples 1 to 5 were slit in the production process, so the resulting laminate did not have a narrow recess on the side, and sealed It was possible to prevent foaming during vacuum lamination using the material.
Moreover, since the resulting laminate by the method for producing a laminate of Example _{1~5, [W X '] /} [W C] is in the range of 0.7 to 0.98, the sealing material The sealing state of the cross section during the vacuum lamination using was good, and delamination did not occur.

On the other hand, since the manufacturing method of the laminated body of Comparative Example 1 does not slit in the manufacturing process, the obtained laminated body has a narrow concave portion on the side surface, and foamed during vacuum lamination using a sealing material. Was produced.
Moreover, since the laminated body obtained by the method for producing the laminated body of Comparative Example 2 has [W _{X ′} ] / [W _C ] of 1.00, the cross section during the vacuum lamination using the sealing material The sealing state was poor, resulting in delamination.

  According to the method for manufacturing a laminate of the present invention, it is possible to manufacture a laminate that does not have a narrow recess on the side surface. Such a laminate can prevent foaming during vacuum lamination using a sealing material, and can be suitably used as a laminate for protecting electronic devices (particularly, a laminate for protecting solar cells).

1: Sheet A
21, 22: Adhesive layer 3: Sheet C
4: Sheet D
51, 52: Release sheet 6: Slitter 10: Laminate 11: Protruding part 20: Sealing material 30: Electronic device

Claims (14)

The manufacturing method of a laminated body which performs the process of the following (1)-(3) in order.
(1) Step of producing laminate X having adhesive layer B ₁ on sheet A (2) Step of slitting both ends of laminate X in the width direction to make laminate X ′ (3) Adhesive layer B _{1. A process} of laminating a sheet C having a width W _C wider than the width W _{X ′} of the laminated body X ′ so that both ends of the sheet C protrude from both ends of the adhesive layer B _{1 [W X '] / [W} C] is 0.7 to 0.98, method for producing a laminate according to claim 1. In the step (1), a laminate X having a release sheet ₁ on the adhesive layer B ₁ is prepared. After the step (2) and before the sheet C is bonded, through the step of peeling the release sheet _1, method for producing a laminate according to claim 1 or 2. In the step (1), the adhesive layer B ₁ composition is applied on the release sheet ₁ and dried to form the adhesive layer B ₁ , and then laminated by bonding the sheet A to the adhesive layer B _1. The manufacturing method of the laminated body of Claim 3 which produces the body X.   The manufacturing method of the laminated body in any one of Claims 1-4 which performs the said process (3) using an edge position control apparatus. In the step (1), as a laminate X, the adhesive layer B ₁ sheet A to produce those having the adhesive layer B ₂ on the opposite side, according to any one of claims 1 to 5 A manufacturing method of a layered product. Between the steps (2) and (3) or after the step (3), the width of the sheet C is wider on the adhesive layer B ₂ than the width W _{X ′} of the laminate X ′. the sheet D having a width W _D than W _C, both ends of the sheet D undergoes a step of bonding so as to protrude from both ends of the adhesive layer B _2, the method for manufacturing a laminate according to claim 6. In the step (1), a laminate X having a release sheet ₂ on the adhesive layer B ₂ is prepared. After the step (2) and before the sheet D is bonded, through the step of peeling the release sheet _2, the manufacturing method of the laminate according to claim 7. In the step (1), after the laminate X is coated with the adhesive layer B ₂ composition on the release sheet ₂ and dried to form the adhesive layer B ₂ , the sheet A is applied to the adhesive layer B _2. The manufacturing method of the laminated body of Claim 8 produced by bonding.   The manufacturing method of the laminated body in any one of Claims 7-9 whose thickness of the said sheet | seat D is 60 micrometers or more.   The manufacturing method of the laminated body in any one of Claims 1-10 whose said sheet | seat C is a weatherproof sheet.   The manufacturing method of the laminated body in any one of Claims 1-11 whose said sheet | seat A is a moisture-proof sheet.   The manufacturing method of the laminated body in any one of Claims 1-12 whose said laminated body is a laminated body for electronic device protection.   The manufacturing method of the laminated body of Claim 13 whose said electronic device is a solar cell.