JP2019077733A - Resin sheet, laminated glass, and solar cell module - Google Patents

Abstract

To provide a resin sheet which is excellent in transparency and bubble prevention properties, suppresses generation of gel, and comprises an ethylene-vinyl acetate copolymer.SOLUTION: A resin sheet to be used as an intermediate film 101 for laminated glass or a solar cell sealing material contains an ethylene-vinyl acetate copolymer, a carbonate-based organic peroxide as a crosslinking agent, and a cyanurate compound as a crosslinking aid. The content of the carbonate-based organic peroxide in the resin sheet is 1.0-1.5 pts.mass based on 100 pts.mass of the ethylene-vinyl acetate copolymer. The content of the cyanurate compound is 1.2-1.5 pts.mass based on 100 pts.mass of the ethylene-vinyl acetate copolymer.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a resin sheet, a laminated glass and a solar cell module.

  Ethylene / vinyl acetate copolymers are widely used in intermediate films for laminated glass, solar cell sealants, construction materials and the like because they are excellent in insulation and have high transparency.

  As a technique regarding the resin sheet using such an ethylene vinyl acetate copolymer, the thing as described in patent document 1 (WO 2005/090504 pamphlet) is mentioned, for example.

  Patent Document 1 discloses a sheet-like adhesive comprising an ethylene / vinyl acetate copolymer and an organic peroxide.

WO 2005/090504 pamphlet

The state of the art required for various properties of resin sheets using ethylene-vinyl acetate copolymer is becoming higher and higher. The present inventors have found the following problems regarding a resin sheet using a conventional ethylene-vinyl acetate copolymer.
First, in the case of producing a laminated glass or a solar cell module using an ethylene / vinyl acetate copolymer sheet, the ethylene / vinyl acetate copolymer sheet containing a crosslinking agent and a transparent substrate are laminated, and heated and pressed. Each layer is bonded and integrated by curing the ethylene-vinyl acetate copolymer sheet. An organic peroxide is used as the crosslinking agent, and a cyanurate or acrylate compound is generally used as the crosslinking aid.
According to the investigations of the present inventors, the laminated glass and the solar cell module using the resin sheet using the conventional ethylene-vinyl acetate copolymer are inferior in transparency (haze), and generate a bubble, a resin sheet It became clear that it had problems such as gelation occurring during molding.
As described above, the present inventors have found that the resin sheet using the conventional ethylene-vinyl acetate copolymer still has room for improvement in terms of achieving both transparency, bubble prevention and gel suppression. The

  The present invention has been made in view of the above circumstances, and provides a resin sheet made of an ethylene / vinyl acetate copolymer which is excellent in transparency and air bubble preventing property and in which the generation of gel is suppressed.

  The inventors of the present invention conducted intensive studies to achieve the above-mentioned problems. As a result, by using a carbonate-based organic peroxide and a cyanurate compound as the constituent components of the resin sheet, and controlling the blending ratio of these highly, the transparency, the bubble prevention property and the gel suppression are well-balanced. It has been found that it can be improved, and the present invention has been made.

  According to the present invention, the following resin sheet, laminated glass and solar cell module are provided.

[1]
A resin sheet used for an interlayer for laminated glass or a solar cell encapsulant,
Ethylene-vinyl acetate copolymer,
Carbonate organic peroxide which is a crosslinking agent,
A cyanurate compound which is a crosslinking assistant,
Including
The content of the carbonate-based organic peroxide in the resin sheet is 1.0 parts by mass or more and 1.5 parts by mass or less with respect to 100 parts by mass of the ethylene / vinyl acetate copolymer,
The resin sheet whose content of the said cyanurate compound in the said resin sheet is 1.2 mass parts or more and 1.5 mass parts or less with respect to 100 mass parts of said ethylene / vinyl acetate copolymers.
[2]
In the resin sheet as described in the above [1],
The resin sheet in which the said carbonate type organic peroxide contains t-butylperoxy 2-ethylhexyl carbonate.
[3]
In the resin sheet according to the above [1] or [2],
The resin sheet in which the said cyanurate compound contains triallyl cyanurate or triallyl isocyanurate.
[4]
In the resin sheet according to any one of the above [1] to [3],
A resin sheet having an MFR of 10 g / 10 minutes or more and 50 g / 10 minutes or less according to ASTM D1238 and measured under the conditions of 190 ° C. and a 2.16 kg load.
[5]
In the resin sheet according to any one of the above [1] to [4],
The resin sheet whose content of the vinyl acetate unit in the said ethylene * vinyl acetate copolymer is 25 mass% or more and 35 mass% or less.
[6]
In the resin sheet according to any one of the above [1] to [5],
The resin sheet whose mass ratio of content of the said cyanurate compound with respect to content of the said carbonate type organic peroxide in the said resin sheet is 0.9 or more and 1.5 or less.
[7]
In the resin sheet according to any one of the above [1] to [6],
The total content of the carbonate organic peroxide and the cyanurate compound in the resin sheet is 2.3 parts by mass or more and 2.8 parts by mass or less with respect to 100 parts by mass of the ethylene / vinyl acetate copolymer There is a resin sheet.
[8]
In the resin sheet according to any one of the above [1] to [7],
The resin sheet whose content of the said ethylene / vinyl acetate copolymer is 80 mass% or more, when the whole of the resin component contained in the said resin sheet is 100 mass%.
[9]
An intermediate film for glass comprising the resin sheet according to any one of the above [1] to [8],
Transparent substrates provided on both sides of the interlayer film for laminated glass;
Laminated glass.
[10]
In the laminated glass described in [9] above,
Laminated glass used in buildings.
[11]
Front side transparent protective member,
Back side protection member,
Solar cell element,
A sealed body of the resin sheet according to any one of the above [1] to [8], and sealing the solar cell element between the front side transparent protective member and the back side protective member With the tuyere,
Solar cell module equipped with

  According to the present invention, it is possible to provide a resin sheet made of an ethylene / vinyl acetate copolymer which is excellent in transparency and air bubble preventing property and in which the generation of gel is suppressed.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows typically one Embodiment of the laminated glass of this invention. It is sectional drawing which shows typically one Embodiment of the solar cell module of this invention.

  Hereinafter, embodiments of the present invention will be described using the drawings. In all the drawings, the same components are denoted by the same reference numerals, and the description thereof is appropriately omitted. Also, the figure is a schematic view and does not match the actual dimensional ratio. Unless otherwise noted, “A to B” in the numerical range represents A or more and B or less.

1. Resin Sheet The resin sheet according to the present embodiment is a resin sheet used for an interlayer for laminated glass or a solar cell sealing material, and is an ethylene / vinyl acetate copolymer and a carbonate-based organic peroxide which is a crosslinking agent. And a cyanurate compound which is a coagent.
And content of the said carbonate type organic peroxide in the said resin sheet is 1.0 mass part or more and 1.5 mass parts or less with respect to 100 mass parts of said ethylene / vinyl acetate copolymers, The content of the cyanurate compound in the resin sheet is 1.2 parts by mass or more and 1.5 parts by mass or less with respect to 100 parts by mass of the ethylene / vinyl acetate copolymer.

The inventors of the present invention conducted intensive studies to provide a resin sheet composed of an ethylene / vinyl acetate copolymer which is excellent in transparency and air bubble preventing property and in which the generation of gel is suppressed. As a result, by using a carbonate-based organic peroxide and a cyanurate compound as the constituent components of the resin sheet, and by setting the mixing ratio thereof to the above range, the transparency, the bubble prevention property and the gel suppression are well-balanced. I found that I could improve.
That is, the resin sheet according to the present embodiment is excellent in transparency and air bubble preventing property, and can suppress the generation of gel.

  Further, the mass ratio of the content of the cyanurate compound to the content of the carbonate-based organic peroxide in the resin sheet according to the present embodiment is preferably 0.9 or more and 1.5 or less.

  In addition, the total content of the carbonate organic peroxide and the cyanurate compound in the resin sheet according to the present embodiment is preferably 2.3 parts by mass or more with respect to 100 parts by mass of the ethylene / vinyl acetate copolymer. It is 2.8 parts by mass or less.

  The average film thickness of the resin sheet according to the present embodiment is not particularly limited, but is preferably 0.2 mm or more and 2.0 mm or less. The mechanical strength of a resin sheet can be made more favorable as the average film thickness of a resin sheet is more than the said lower limit, and the thermal contraction of a resin sheet can be suppressed. In addition, when the average film thickness of the resin sheet is equal to or less than the upper limit, breakage of other members such as a transparent substrate can be suppressed in the laminating step, and lamination to a transparent substrate can be performed even at a relatively low temperature. Moreover, sufficient light transmittance can be ensured as the average film thickness of a resin sheet is below the said upper limit, and the solar cell module using it has high photovoltaic power generation.

  The content of the ethylene / vinyl acetate copolymer is preferably 80% by mass or more, more preferably 90% by mass or more, still more preferably 95% by mass, based on 100% by mass of the entire resin component contained in the resin sheet. % By weight or more, and particularly preferably 100% by weight. Thereby, the resin sheet excellent in the balance of various characteristics, such as transparency, adhesiveness, heat resistance, a softness | flexibility, an external appearance, a crosslinking characteristic, an electrical property, and extrusion moldability, can be obtained.

  The content of the resin component is preferably 50% by mass or more, more preferably 70% by mass or more, still more preferably 80% by mass or more, particularly preferably 90% by mass, based on 100% by mass of the entire resin sheet. It is above. Thereby, the resin sheet excellent in the balance of various characteristics, such as transparency, adhesiveness, heat resistance, a softness | flexibility, an external appearance, a crosslinking characteristic, an electrical property, and extrusion moldability, can be obtained.

<Ethylene-vinyl acetate copolymer>
The resin sheet according to the present embodiment contains an ethylene-vinyl acetate copolymer as a main component.
The ethylene-vinyl acetate copolymer is a copolymer of ethylene and vinyl acetate, and is usually a random copolymer.

  The melt flow rate (MFR) of the above ethylene-vinyl acetate copolymer measured according to ASTM D 1238 and at a load of 190 ° C. under a load of 2.16 kg is preferably 10 to 50 g / 10 min, more preferably Is 10 to 40 g / 10 min, more preferably 10 to 30 g / 10 min. The MFR of the ethylene / vinyl acetate copolymer can be adjusted by adjusting the polymerization temperature, the polymerization pressure, and the molar ratio of the monomer concentration to the hydrogen concentration of the copolymerization monomer in the polymerization system, etc. it can.

The fluidity of the ethylene-based resin composition containing the ethylene / vinyl acetate copolymer is improved as the MFR is at least the above lower limit value, and the moldability of the resin sheet becomes better.
On the other hand, since molecular weight becomes it large that MFR is below the above-mentioned upper limit, adhesion to a roll surface, such as a chill roll, can be suppressed, peeling becomes unnecessary, and it can be fabricated into a resin sheet of more uniform thickness. Furthermore, since it becomes a resin composition with "stiffness", a thick resin sheet of 0.1 mm or more can be easily molded. In addition, since the crosslinking property is improved, the crosslinking can be sufficiently carried out to suppress the decrease in heat resistance.

The content of the vinyl acetate unit in the ethylene / vinyl acetate copolymer is preferably 25% by mass to 35% by mass, more preferably 28% by mass to 35% by mass, and still more preferably 28% by mass to 33% by mass. % Or less. When the content of the vinyl acetate unit is in this range, the balance among the crosslinkability, the flexibility, the weather resistance and the transparency is further excellent.
The vinyl acetate content can be measured in accordance with JIS K6730.

  When the resin sheet according to the present embodiment is used as a solar cell sealing material, when the content of vinyl acetate is in the above range, crosslinkability, flexibility, adhesion of the solar cell sealing sheet, weatherability Better balance of transparency and mechanical properties. In addition, when forming a solar cell sealing sheet, the film forming property is good.

  The ethylene-vinyl acetate copolymer is preferably a binary copolymer consisting only of ethylene and vinyl acetate, but in addition to ethylene and vinyl acetate, for example, vinyl formate, vinyl glycolate, vinyl propionate, vinyl benzoate and the like Etc .; acrylic monomers such as acrylic acid, methacrylic acid, ethacrylic acid, or acrylic monomers such as salts or alkyl esters thereof; Good. When the copolymer component other than ethylene and vinyl acetate is contained, the amount of the copolymer component other than ethylene and vinyl acetate in the ethylene / vinyl acetate copolymer may be 0.5% by mass or more and 5% by mass or less preferable.

  Two or more ethylene / vinyl acetate copolymers different in vinyl acetate content, MFR, etc. may be used in combination. When two or more ethylene / vinyl acetate copolymers are used, the total amount of these is preferably in the above range.

  The manufacturing method of the said ethylene vinyl acetate copolymer is not specifically limited, It can manufacture by a well-known method. For example, in the presence of a radical generator, at 500 to 4000 atm at 100 to 300 ° C. in the presence or absence of a solvent or a chain transfer agent, ethylene, vinyl acetate, and, if necessary, copolymerization of other copolymer components It can be manufactured by

<Crosslinking agent>
The resin sheet according to the present embodiment contains a carbonate-based organic peroxide which is a crosslinking agent.
In the resin sheet according to the present embodiment, the inclusion of the carbonate-based organic peroxide improves the crosslinking speed of the ethylene / vinyl acetate copolymer.

The content of the carbonate-based organic peroxide in the resin sheet according to the present embodiment is 1.0 parts by mass or more and 1.5 parts by mass or less, preferably 100 parts by mass of the ethylene / vinyl acetate copolymer. 1.1 parts by mass or more and 1.3 parts by mass or less.
The crosslinking characteristic of a resin sheet becomes favorable for content of a carbonate system organic peroxide to be more than the said lower limit, and the heat resistance of a resin sheet improves. In addition, the grafting reaction of the silane coupling agent to the main chain of the ethylene / vinyl acetate copolymer is improved to improve heat resistance and adhesion. Furthermore, the transparency of the resin sheet is improved.
In addition, when the content of the carbonate-based organic peroxide is less than or equal to the above upper limit, the above-mentioned crosslinking properties, heat resistance and adhesiveness are good, and gelation at the time of sheet formation can be suppressed, and the sheet appearance is good. Resin sheet can be obtained. Furthermore, the generation amount of decomposition products of the carbonate-based organic peroxide and the like can be reduced, and the generation of air bubbles in the resin sheet can be suppressed. Furthermore, the scorch resistance of a resin sheet can be made favorable as content of a carbonate system organic peroxide is below the said upper limit.

Examples of carbonate organic peroxides include t-butylperoxyisopropyl carbonate, t-butylperoxy-2-ethylhexyl carbonate, t-amylperoxyisopropyl carbonate, and t-amylperoxy-2-ethylhexyl carbonate. It can be mentioned. Among these, t-butylperoxy-2-ethylhexyl carbonate is preferable.
The carbonate organic peroxides may be used singly or in combination of two or more.

<Crosslinking Aid>
The resin sheet according to the present embodiment contains a cyanurate compound which is a crosslinking assistant, from the viewpoint of improving the crosslinkability.
As a cyanurate compound, 1 type, or 2 or more types selected from triallyl cyanurate, triallyl isocyanurate etc. can be used, for example. Among these, the cyanurate compound preferably contains triallyl isocyanurate.

  The content of the cyanurate compound in the resin sheet according to the present embodiment is 1.2 parts by mass or more and 1.5 parts by mass or less, preferably 1.2 parts by mass with respect to 100 parts by mass of the ethylene / vinyl acetate copolymer. More than mass part and 1.4 mass parts or less.

The crosslinking characteristic of a resin sheet becomes favorable for content of a cyanurate compound to be more than the said lower limit, and the heat resistance of a resin sheet improves. In addition, the grafting reaction of the silane coupling agent to the main chain of the ethylene / vinyl acetate copolymer is improved to improve the heat resistance and the adhesion. Furthermore, the transparency of the resin sheet is improved.
Further, when the content of the cyanurate compound is not more than the above upper limit, in addition to the above-mentioned cross-linking characteristics, heat resistance and adhesiveness being good, gelation at the time of sheet formation can be suppressed and a resin sheet having a good sheet appearance is obtained. You can get it. Furthermore, the scorch resistance of a resin sheet can be made favorable as content of a cyanurate compound is below the said upper limit.

<Silane coupling agent>
The resin sheet according to the present embodiment may further contain a silane coupling agent.
The content of the silane coupling agent in the resin sheet according to the present embodiment is preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the ethylene / vinyl acetate copolymer, and 0.1 to 4 It is more preferable that it is a mass part, and it is especially preferable that it is 0.1-3 mass parts.

Adhesiveness improves that content of a silane coupling agent is more than the said lower limit.
On the other hand, when the content of the silane coupling agent is less than or equal to the above upper limit value, the cost and the performance are well balanced, and the decrease in moisture permeability can be prevented. Moreover, when it uses as a solar cell sealing material, adhesiveness with a surface side transparent protective member, a cell, an electrode, and a back surface side protective member becomes favorable, and adhesiveness also improves. In addition, the silane coupling agent itself causes a condensation reaction to be present in the solar cell sealing material as white streaks, which can suppress deterioration of the product appearance.

  As the silane coupling agent, those known in the art can be used without particular limitation. Specifically, vinyltriethoxysilane, vinyltrimethoxysilane, vinyltris (β-methoxyethoxysilane), γ-glycidoxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane Etc. can be used. Preferably, γ-glycidoxypropylmethoxysilane, γ-aminopropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltriethoxysilane and the like, which have good adhesion, can be mentioned.

<UV absorber, light stabilizer, heat stabilizer>
The resin sheet according to the present embodiment may further contain at least one additive selected from an ultraviolet light absorber, a light stabilizer, and a heat resistant stabilizer. It is preferable that the compounding quantity of these additives is 0.005-5 mass parts with respect to 100 mass parts of ethylene vinyl acetate copolymers. Furthermore, it is preferable to contain at least two types of additives selected from the above three types, and in particular, it is preferable that all the above three types be contained. When the compounding amount of the above-mentioned additive is within the above range, the effect of improving the weathering stability and the heat resistance stability can be sufficiently ensured, and the lowering of the transparency and the adhesion to the glass plate can be prevented. So preferred.

  Specific examples of UV absorbers include 2-hydroxy-4-normal-octyloxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2,2-dihydroxy-4-methoxybenzophenone and 2-hydroxy-4-methoxy Benzophenone UV absorbers such as -4-carboxybenzophenone and 2-hydroxy-4-N-octoxybenzophenone; 2- (2-hydroxy-3,5-di-t-butylphenyl) benzotriazole, 2- (2) Benzotriarisole ultraviolet absorbers such as -hydroxy-5-methylphenyl) benzotriazole; salicylic acid ester ultraviolet absorbers such as phenyl salicylate, p-octylphenyl salicylate, etc. are used.

  As a light stabilizer, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, poly [{6- (1,1,3,3-tetramethylbutyl) amino-1,3,6 5-triazine-2,4-diyl} {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino} Hindered amine light stabilizers such as H], hindered piperidine light stabilizers and the like are preferably used.

  Specific examples of the heat resistant stabilizer include tris (2,4-di-tert-butylphenyl) phosphite and bis [2,4-bis (1,1-dimethylethyl) -6-methylphenyl] ethyl ester Phosphorous acid, tetrakis (2,4-di-tert-butylphenyl) [1,1-biphenyl] -4,4′-diylbisphosphonite, and bis (2,4-di-tert-butylphenyl) Phosphite type heat resistant stabilizers such as pentaerythritol diphosphite; Lactone heat resistant stabilizers such as reaction product of 3-hydroxy-5,7-di-tert-butyl-furan-2-one with o-xylene; 3,3 ', 3 ", 5, 5', 5" -hexa-tert-butyl-a, a ', a "-(methylene-2,4,6-triyl) tri-p-cresol, 1,3 5-trimethyl- 2,4,6-Tris (3,5-di-tert-butyl-4-hydroxyphenyl) benzylbenzene, pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] , Octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, thiodiethylene bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], etc. These heat resistant stabilizers include sulfur based heat resistant stabilizers, amine based heat resistant stabilizers etc. These may be used singly or in combination of two or more. Stabilizers and hindered phenolic heat stabilizers are preferred.

<Other additives>
The resin sheet which concerns on this embodiment can be suitably included in the range which does not impair the objective of this invention except various components detailed above. For example, various polyolefins other than the above-mentioned ethylene / vinyl acetate copolymer, a styrene system, an ethylene system block copolymer, a propylene polymer etc. are mentioned. These may be contained in an amount of preferably 0.0001 to 50 parts by mass, more preferably 0.001 to 40 parts by mass, with respect to 100 parts by mass of the ethylene / vinyl acetate copolymer. In addition, it is a kind of resin selected from various resins other than polyolefin, and / or various rubbers, plasticizers, fillers, pigments, dyes, antistatic agents, antibacterial agents, fungicides, flame retardants, cross-linking aids, dispersing agents, etc. The above additives can be suitably contained.

2. Method of Manufacturing Resin Sheet Hereinafter, an example of a method of manufacturing a resin sheet according to the present embodiment will be described.
First, ethylene / vinyl acetate copolymer, carbonate organic peroxide, cyanurate compound and, if necessary, silane coupling agent, ultraviolet absorber, light stabilizer, heat stabilizer, Furthermore, if necessary, it is blended with other additives using, for example, manual blending in a bag such as a plastic bag or using a stirring mixer such as a Henschel mixer, tumbler, super mixer, or the like. Next, the obtained resin composition is introduced into, for example, a hopper of an extrusion sheet molding machine, and the resin composition is extruded into a sheet form from a T-die of the extrusion sheet molding machine while melt kneading is performed to obtain a resin sheet.

  As an extrusion temperature range, extrusion temperature is 100-250 degreeC, for example. If the extrusion temperature is in the above range, a better sheet can be obtained.

3. Although the use of the resin sheet which concerns on this embodiment is not specifically limited, It is preferable to use as an intermediate film for laminated glasses.
The laminated glass of the present embodiment may use the resin sheet according to the present embodiment as an intermediate film for laminated glass. The laminated glass which concerns on this embodiment is laminated glass which an appearance defect does not produce easily.

FIG. 1 is a cross-sectional view schematically showing an embodiment of the laminated glass 100 of the present invention.
The laminated glass 100 is provided with the intermediate film 101 for laminated glass containing the resin sheet concerning this embodiment, and the transparent substrate 103 provided in the both surfaces of the intermediate film 101 for laminated glass.
In order to produce the laminated glass 100, for example, as shown in FIG. 1, the resin sheet according to the present embodiment is used as the interlayer for laminated glass 101, and the interlayer for laminated glass 101 is between two transparent substrates 103. After holding, the method of heating and pressurizing etc. is used.
These steps are performed using, for example, a vacuum bag method, a nip roll method, or the like. Thereby, the intermediate film 101 for laminated glass is cured, and the intermediate film 101 for laminated glass and the two transparent substrates 103 can be bonded and integrated. As the manufacturing conditions, for example, the ethylene-vinyl acetate copolymer is crosslinked by preliminarily pressure-bonding the above-mentioned laminate at a temperature of 80 to 120 ° C. and heat treatment at 100 to 150 ° C. for 10 minutes to 1 hour. Further, the heat treatment may be performed under pressure.

The transparent substrate 103 is, for example, a glass plate such as a green glass plate, a silicate glass plate, an inorganic glass plate, an uncolored transparent glass plate, etc .; polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethylene butyrate, polymethyl methacrylate A substrate or film made of plastic such as (PMMA) can be used. Glass plates are preferred in view of weatherability, impact resistance, and the like.
The thickness of the transparent substrate 103 is generally about 1 to 20 mm. The transparent substrates 103 disposed on both sides of the laminated glass 100 may be the same, or different substrates may be used in combination. The combination is determined in consideration of the strength of the substrate and the application of the laminated glass.

  Laminated glass 100 is a material for buildings and vehicles (cars, railway vehicles, ships); electronic devices such as plasma displays; doors and walls of various devices such as refrigerators and heat retaining devices; used in various applications can do. Among these, it can be particularly suitably used for buildings.

4. Solar cell module The application of the resin sheet according to the present embodiment is not particularly limited, but it is preferable to use as a solar cell sealing material.
The solar cell sealing material (it also calls a solar cell sealing material sheet | seat) comprised by the resin sheet which concerns on this embodiment is used in order to seal a solar cell element in a solar cell module.
The solar cell module is, for example, a crystalline solar cell in which a solar cell sealing material sheet, which is usually formed of single crystal silicon, polycrystalline silicon or the like, is sandwiched between solar cell sealing material sheets, and both surfaces are covered with protective sheets. There is a module. That is, a typical solar cell module includes a protective sheet for a solar cell module (surface-side transparent protective member) / a light-receiving surface-side sealing layer / a solar cell element / a back surface-side sealing layer / a protective sheet for a solar cell module It is configured as a protection member). Here, the solar cell sealing material of the present embodiment is used to form either or both of the light receiving surface side sealing layer and the back surface side sealing layer, and these sealing layers are resin sheets. It can be formed by crosslinking.
However, the solar cell module, which is one of the preferred embodiments of the present invention, is not limited to the above configuration, and some of the above layers may be omitted as appropriate, as long as the object of the present invention is not impaired. Other layers can be provided as appropriate. Examples of the layer other than the above include an adhesive layer, an impact absorbing layer, a coating layer, an antireflective layer, a back surface rereflection layer, a light diffusion layer and the like. These layers are not particularly limited, but can be provided at appropriate positions in consideration of the purpose and characteristics of providing each layer.

In FIG. 2, an example of sectional drawing of the solar cell module of this embodiment is shown.
The solar cell module 10 includes a plurality of solar cell elements 13, a pair of light receiving surface side solar cell sealing material sheets 11 and a back surface side solar cell sealing material sheet 12 which seal the solar cell elements 13 with sandwiching the solar cell elements 13. A transparent protection member 14 and a back surface protection member (back sheet) 15 are provided.

(Solar cell element)
Examples of the solar cell element 13 include single crystal silicon, silicon such as polycrystalline silicon and amorphous silicon, III-V and II-VI compound semiconductors such as gallium-arsenic, copper-indium-selenium, and cadmium-tellurium. Various solar cell elements can be used.
In the solar cell module 10, the plurality of solar cell elements 13 are electrically connected in series via an interconnector 16 provided with a lead and a solder joint.

(Front side transparent protective member)
Examples of the surface-side transparent protective member 14 include transparent substrates such as glass plates; resin plates formed of acrylic resin, polycarbonate, polyester, fluorine-containing resin, and the like.
The solar cell encapsulant sheet of the present embodiment exhibits good adhesion to the front transparent protective member 14.

(Back side protection member)
As the back surface side protection member (back sheet) 15, single sheets or multilayer sheets, such as metal and various thermoplastic resin films, are mentioned. Examples thereof include metals such as tin, aluminum and stainless steel; inorganic materials such as glass; polyesters, inorganic evaporated polyesters, fluorine-containing resins, various thermoplastic resin films formed of polyolefins and the like, and the like.
The back surface side protection member 15 may be a single layer or a multilayer.
The solar cell encapsulant sheet of the present embodiment exhibits good adhesion to the back surface side protective member 15.

<Method of manufacturing solar cell module>
Although the manufacturing method of the solar cell module in this embodiment is not specifically limited, For example, the following method is mentioned.
First, the plurality of solar cell elements 13 electrically connected using the interconnector 16 are sandwiched between the pair of light receiving surface side solar cell sealing material sheets 11 and the back surface side solar cell sealing material sheet 12, and these light receiving surface sides A laminate is manufactured by sandwiching the solar cell sealing material sheet 11 and the back surface side solar battery sealing material sheet 12 between the front surface side transparent protective member 14 and the rear surface side protective member 15. Then, the laminate is heated, and the light receiving surface side solar cell sealing material sheet 11 and the back surface side solar battery sealing material sheet 12 and the light receiving surface side solar cell sealing material sheet 11 and the front surface transparent protective member 14 The solar cell sealing material sheet 12 and the back surface side protection member 15 are bonded.
In the production of a solar cell module, a resin sheet is prepared in advance, and pressure is applied at a temperature at which the resin sheet melts, for example, at a lamination temperature of 145 to 170 ° C. and a vacuum pressure of 10 Torr or less. Heat under vacuum for 5-10 minutes. Then, pressurization by atmospheric pressure may be performed for about 2 to 30 minutes to form a module configured as described above. In this case, the resin sheet has excellent cross-linking properties by containing a specific cross-linking agent, and there is no need to go through a two-step adhesion process in forming a module and it can be completed in a short time at high temperature And the productivity of the module can be significantly improved. Moreover, it is also possible to go through a two-step bonding process using an oven etc. When going through a two-step bonding process, for example, heating is performed in the range of 120 to 170 ° C. for 1 to 120 minutes to produce a module It is also possible.

  As mentioned above, although embodiment of this invention was described, these are the illustrations of this invention, and various structures other than the above can also be employ | adopted.

  EXAMPLES Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited to these examples.

Example 1
1. Production of Resin Sheet A resin composition was produced as follows for Examples 1 to 6 and Comparative Examples 1 to 6. First, a resin composition was obtained by blending ethylene / vinyl acetate copolymer (EVA), a crosslinking agent, a crosslinking aid, a silane coupling agent, a light stabilizer, and a heat stabilizer with the formulation shown in Table 1 .

In addition, the unit of the compounding ratio of each component in Table 1 is a mass part. Moreover, the detail of each component in Table 1 is as follows.
・ EVA1: ethylene-vinyl acetate copolymer (vinyl acetate content 28 mass%, MFR: 15 g / 10 minutes)
-EVA2: ethylene-vinyl acetate copolymer (vinyl acetate content 28 mass%, MFR: 30 g / 10 minutes)
Cross-linking agent: t-butylperoxy-2-ethylhexyl carbonate Cross-linking aid: triallyl isocyanurate silane coupling agent: γ-methacryloxypropyltrimethoxysilane Light stabilizer: bis (2,2, 6 2,6-Tetramethyl-4-piperidyl) sebacate UV absorber: 2-hydroxy-4-normo-octyloxybenzophenone Heat-resistant stabilizer: octadecyl-3- (3,5-di-tert-butyl-4-hydroxy) Phenyl) propionate

<Evaluation of scorch resistance>
The above resin composition was melt extruded in the form of a sheet by a single-screw extruder (screw diameter: 30 mmφ) under the condition of a die temperature of 105 ° C. The sheet thickness at this time was 0.45 mm. The extruded sheet surface was visually confirmed, and the evaluation results were classified as follows.
No gel: ○
With gel: x

<Haze evaluation>
A laminate of the resin sheet and the glass plate obtained by the scorch resistance evaluation was produced according to the following method.
Between two 3.2 mm thick blue plate float glass made by Asahi Glass Fabritech cut into 120 mm wide × 75 mm long size, four 0.45 mm thick resin sheets cut into 120 mm wide × 75 mm long Stacked. Using a vacuum laminator (manufactured by NPC: LM-110 × 160-S), lamination was carried out at a heating plate temperature of 130 ° C., with a vacuum time of 3 minutes and a pressure time of 30 minutes.
The obtained laminated body was thrown into the oven (The Tabai Espec Corporation make: PHH-401) set to 100 degreeC. After 15 minutes, the oven was turned off and left overnight to cool.
The haze of the gradually cooled laminate was measured using NDH5000 manufactured by Nippon Denshoku Kogyo Co., Ltd., and the evaluation results were classified as follows.
≦ 0.8%: ○
0.8% <: x

<Air bubble generation confirmation evaluation>
A laminate of the resin sheet and the glass plate obtained by the scorch resistance evaluation was produced according to the following method.
One 0.45 mm-thick resin sheet cut into 120 mm wide × 75 mm long between two 3.2 mm thick blue float glass made by Asahi Glass Fabritech cut into 120 mm wide × 75 mm long size Stacked. Using a vacuum laminator (manufactured by NPC: LM-110 × 160-S), lamination was carried out at a heating plate temperature of 150 ° C., for a vacuum time of 3 minutes and a pressure time of 10 minutes.
The obtained laminate was visually confirmed, and the evaluation results were classified as follows.
No bubble generation: ○
Bubble generation: ×

  The resin sheets of Examples 1 to 6 were excellent in transparency and air bubble-preventing property, and the generation of gel was also suppressed.

DESCRIPTION OF SYMBOLS 100 Laminated glass 101 Intermediate film for laminated glass 103 Transparent substrate 10 Solar cell module 11 Light receiving surface side solar cell sealing material sheet 12 Back surface side solar cell sealing material sheet 13 Solar cell element 14 Surface side transparent protective member 15 Back surface side protective member 16 interconnectors

Claims (11)

A resin sheet used for an interlayer for laminated glass or a solar cell encapsulant,
Ethylene-vinyl acetate copolymer,
Carbonate organic peroxide which is a crosslinking agent,
A cyanurate compound which is a crosslinking assistant,
Including
The content of the carbonate-based organic peroxide in the resin sheet is 1.0 parts by mass or more and 1.5 parts by mass or less with respect to 100 parts by mass of the ethylene / vinyl acetate copolymer,
The resin sheet whose content of the said cyanurate compound in the said resin sheet is 1.2 mass parts or more and 1.5 mass parts or less with respect to 100 mass parts of said ethylene / vinyl acetate copolymers. In the resin sheet according to claim 1,
The resin sheet in which the said carbonate type organic peroxide contains t-butylperoxy 2-ethylhexyl carbonate. In the resin sheet according to claim 1 or 2,
The resin sheet in which the said cyanurate compound contains triallyl cyanurate or triallyl isocyanurate. The resin sheet according to any one of claims 1 to 3.
A resin sheet having an MFR of 10 g / 10 minutes or more and 50 g / 10 minutes or less according to ASTM D1238 and measured under the conditions of 190 ° C. and 2.16 kg load. The resin sheet according to any one of claims 1 to 4.
The resin sheet wherein the content of vinyl acetate units in the ethylene / vinyl acetate copolymer is 25% by mass or more and 35% by mass or less. The resin sheet according to any one of claims 1 to 5,
The resin sheet whose mass ratio of content of the said cyanurate compound with respect to content of the said carbonate type organic peroxide in the said resin sheet is 0.9 or more and 1.5 or less. The resin sheet according to any one of claims 1 to 6,
The total content of the carbonate organic peroxide and the cyanurate compound in the resin sheet is 2.3 parts by mass or more and 2.8 parts by mass or less with respect to 100 parts by mass of the ethylene / vinyl acetate copolymer There is a resin sheet. In the resin sheet according to any one of claims 1 to 7,
The resin sheet whose content of the said ethylene / vinyl acetate copolymer is 80 mass% or more, when the whole of the resin component contained in the said resin sheet is 100 mass%. An intermediate film for glass comprising the resin sheet according to any one of claims 1 to 8.
Transparent substrates provided on both sides of the interlayer film for laminated glass;
Laminated glass. In the laminated glass according to claim 9,
Laminated glass used in buildings. Front side transparent protective member,
Back side protection member,
Solar cell element,
A sealing layer which is a crosslinked body of the resin sheet according to any one of claims 1 to 8, and which seals the solar cell element between the front side transparent protective member and the back side protective member ,
Solar cell module equipped with

Images