JP2016152389A - Method of manufacturing solar battery module - Google Patents

Abstract

SOLUTION: A method of manufacturing a solar battery module by sealing a solar battery element matrix with resin, the solar battery element matrix being configured so that plural solar battery elements interposed between a transparent panel and a panel or between a transparent panel or a back sheet are connected to one another, comprises: (1) a step of disposing an unvulcanized silicon rubber sheet on one surface of the transparent panel under reduced pressure to prepare a first laminate body; (2) a step of disposing the silicon rubber sheet on one surface of the panel or the back sheet under reduced pressure to prepare a second laminate body; (3) a step of arranging the first laminate body and the second laminate body so that the silicon rubber sheet surfaces thereof confront each other, disposing the solar battery matrix between the silicon rubber sheets, reducing the pressure under the above state and pressing the first and second laminate bodies to seal the solar battery matrix; and (4) a step of heating the sealed laminate bodies to cure the silicon rubber sheets.EFFECT: A solar battery module which can suppress intake of bubbles and is excellent in durability can be manufactured.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a method for manufacturing a solar cell module in which a solar cell element matrix is resin-sealed.

  As measures for ensuring high efficiency of solar cell modules and long-term reliability over 20 to 30 years, reports and proposals focusing on sealing materials have been made. In terms of high efficiency, the silicone material has a light transmittance characteristic in the vicinity of a wavelength of 300 to 400 nm as compared with an ethylene-vinyl acetate copolymer (hereinafter abbreviated as EVA), which is the mainstream sealing material. The superiority of the internal quantum efficiency based on this is reported (for example, see Non-Patent Document 1), and a comparison experiment of output power when actually using EVA and a silicone material as a sealing material is also reported (for example, non-patent document 1). Patent Document 2). Furthermore, in terms of long-term reliability, the module using silicone as the sealing material may have a maximum output deterioration rate of only -0.22% / year even after 29 years of outdoor exposure. Have been reported (for example, see Non-Patent Document 3).

  The use of silicone material as a sealing material has already been achieved in the production of solar cells for space use in the early 1970s. Since there was a problem of workability at the time of sealing, it was replaced with EVA that was low-cost at that time and could be supplied by film.

  However, in recent years, the high efficiency and long-term reliability of solar cells have been renewed, and at the same time, the performance as a sealing material for silicone materials, such as low modulus, high transparency, and high weather resistance, has been reviewed, Various new sealing methods using silicone materials have also been proposed.

  For example, as a method using a silicone sheet, JP 2009-515365 A (Patent Document 1) proposes sealing with a hot-melt type sheet mainly composed of organic polysiloxane. However, it is difficult to process into a sheet shape while maintaining high transparency. For example, in order to process to a thickness of about 1 mm, due to its “brittleness”, it is limited to a processing method such as a casting method or a press method, Not suitable for mass production. In Japanese translation of PCT publication No. 2010-505670 (Patent Document 2), a polysiloxane-urea copolymer is proposed as a thermoplastic silicone sheet. However, the transparency on the low wavelength side may be inferior to that of polysiloxane, and the cost for producing the copolymer may increase.

  On the other hand, as a method of using a liquid silicone composition (liquid silicone material), Japanese Patent Application Publication No. 2007-527109 (Patent Document 3) discloses that a liquid silicone composition is connected on or in a liquid silicone material coated on a substrate. It has been proposed to arrange a solar cell by a multi-axis robot and then encapsulate the liquid silicone material without taking in bubbles by curing the liquid silicone material. Moreover, in Japanese translations of PCT publication No. 2011-514680 (patent document 4), it is proposed to use a cell press having a movable plate, and to enclose without taking in bubbles by arranging solar cells under vacuum. Has been. However, any of these methods is significantly different from the conventional solar cell sealing method, and there is a possibility that the current mass production apparatus cannot cope.

  On the other hand, as a method of using an adhesive material such as silicone rubber as a sealing material, Japanese Patent Laid-Open No. 10-275828 (Patent Document 5) uses a sealing material in which a plurality of “ana” is formed. A method of using it has been proposed. Furthermore, as a method of using a millable uncured silicone rubber material as a sealing material, Japanese Patent Application Laid-Open No. 10-321888 (Patent Document 6) discloses a method for improving the adhesiveness of an uncured silicone rubber surface. A method of applying organic fine powder to one or both sides of a rubber sheet has been proposed. Japanese Patent Application Laid-Open No. 2010-158897 (Patent Document 7) also contains an adhesion promoter on one of the silicone layers obtained by curing an addition-curable silicone composition containing an adhesion promoter. A method of applying an addition-curable silicone composition and curing the composition has been proposed. In general, in the process of laminating a sheet to a base material without any gap, for example, a roll laminator used in the process of laminating a semiconductor dry film resist to a base material, or a special used for laminating a liquid crystal film to a substrate A sheet laminating apparatus has been proposed. However, in any of these methods, in particular, in order to use a sticky sheet as a sealing material for a solar cell module, it is necessary to introduce new processing and new equipment after molding as a sheet, resulting in a low manufacturing cost. May be high.

Special table 2009-515365 Special table 2010-505670 Special table 2007-527109 gazette Special table 2011-514680 gazette Japanese Patent Laid-Open No. 10-275828 JP-A-10-321888 JP 2010-158897 A

S. Ohl, G .; Hahn, “Increased internal quantum efficiency of encapsulated solar cell by using two-component silicon as Encapsulant material”, Proc. 23rd, EU PVSEC, Valencia (2008), pp. 2693-2697 Barry Ketola, Chris Shirk, Philip Griffith, Gabriela Bunea, “DEMONSTRATION OF THE BENEFITS OF SILICONE ENCAPSULATION OF PV MODULE Atsuo Ito, Hiroto Owada, Satoshi Furugo, Kazuaki Kinjo, Naoki Yamakawa, Atsushi Yanaginuma, Tomio Imabata, Momoki Watanabe, Sadao Sakamoto: Proceedings of the 9th Next Generation Solar Power System Symposium, 2012, p. 54

  The present invention has been made in view of the above circumstances. When sealing a solar cell element matrix using an unvulcanized silicone rubber sheet made of a millable type silicone rubber composition as a sealing material, Incorporation of voids can be controlled without damaging the solar cell elements using conventional solar cell module manufacturing equipment, and it can be operated at room temperature until the unvulcanized silicone rubber sheet is cured. Furthermore, it aims at providing the manufacturing method of the solar cell module which can manufacture the solar cell module excellent in durability further.

In order to achieve the above object, the present invention provides the following method for manufacturing a solar cell module.
[1] The sun for manufacturing a solar cell module by resin-sealing a solar cell element matrix formed by connecting a plurality of solar cell elements interposed between transparent panels or between a transparent panel and a back sheet In the battery module manufacturing method,
(1) A step of preparing a first laminate in which an unvulcanized silicone rubber sheet made of a millable type silicone rubber composition is bonded to one surface of a transparent panel at a temperature between 10 ° C. and 50 ° C. under reduced pressure;
(2) A step of preparing a second laminate in which an unvulcanized silicone rubber sheet made of a millable type silicone rubber composition is attached to one surface of a panel or a back sheet at 10 ° C. to 50 ° C. under reduced pressure; ,
(3) The first laminated body and the second laminated body are arranged with their silicone rubber sheet surfaces facing each other, and a solar cell matrix is arranged therebetween, and the pressure is reduced between 10 ° C. and 50 ° C. in that state. And pressing the first laminate and the second laminate to seal the solar cell matrix;
(4) A step of heating the sealed laminated body between 70 ° C. and 150 ° C. for 20 to 50 minutes to cure the silicone rubber sheet;
The manufacturing method of the solar cell module characterized by having.
[2] The step (2) is a step of preparing a backsheet-silicone rubber composite in which an unvulcanized silicone rubber made of a millable type silicone rubber composition is topped on one side of the backsheet by a calendar method. [1] The method for manufacturing a solar cell module according to [1].
[3] The silicone rubber composition is
(A) The following average composition formula (I)
R ¹ _a SiO _{(4-a) / 2} (I)
(In the formula, R ¹ represents the same or different unsubstituted or substituted monovalent hydrocarbon group, and a is a positive number of 1.95 to 2.05.)
100 parts by mass of an organopolysiloxane having at least two alkenyl groups in one molecule represented by
(B) 10 to 150 parts by mass of reinforcing silica having a specific surface area of 50 m ² / g or more,
(C) Hardener (A) The manufacturing method of the solar cell module of [1] or [2] characterized by including the effective amount which hardens | cures a component.
[4] The method for producing a solar cell module according to [3], wherein the component (C) is a combination of an organohydrogenpolysiloxane and a hydrosilylation reaction catalyst, or an organic peroxide.

  According to the method for manufacturing a solar cell module of the present invention, the transparent panel and the panel or the backsheet are pressed under reduced pressure, for example, using an existing vacuum laminator device without newly introducing a pasting device. This makes it possible to paste an unvulcanized silicone rubber sheet without any gaps, greatly increasing the intake of air bubbles (voids) between the transparent panel and the panel or back sheet and the unvulcanized silicone rubber sheet. Can be suppressed.

  In addition, the solar cell element matrix is sandwiched between a transparent panel pasted with an unvulcanized silicone rubber sheet, and a panel or backsheet pasted with an unvulcanized silicone rubber sheet, and the above process is performed under reduced pressure (vacuum). Subsequently, pressing can be performed near room temperature (10 ° C. to 50 ° C.). That is, since the heating plate in the apparatus such as a vacuum laminator can be used without heating, the deterioration of the apparatus and apparatus parts due to heating can be suppressed, the running cost of the apparatus can be reduced, and further the working environment can be reduced. Improvement or worker safety can also be improved.

  In addition, by preparing a backsheet-silicone rubber composite in which unvulcanized silicone rubber is topped by a calendar method on one side of a panel or a backsheet, a step of attaching using a vacuum laminator is omitted. Therefore, the work efficiency can be improved.

It is an example of the process which prepares the 1st laminated body of the manufacturing method of the solar cell module which concerns on this invention, and is sectional drawing of the process using a vacuum laminator, (1) is an unvulcanized | cured material with a protective sheet on one side. A state in which a silicone rubber sheet is placed on a transparent panel and set in a vacuum laminator. (2) is a state in which the upper and lower chambers in the vacuum laminator are decompressed by a vacuum pump or the like. (3) is an atmospheric pressure in the upper chamber. A state where the unvulcanized silicone rubber sheet is attached to the transparent panel by pressing the protective sheet through the protective sheet for a predetermined time, and (4) is released from the vacuum laminator chamber and the protective sheet is removed from the vacuum laminator chamber. The state which peels and obtains a 1st laminated body is shown. It is an example of the process which prepares the 2nd laminated body of the manufacturing method of the solar cell module which concerns on this invention, and is sectional drawing of the process using a vacuum laminator, (1) is an unvulcanized | cured material with a protective sheet on one side. A state in which the silicone rubber sheet is placed on the back sheet and set in the vacuum laminator, (2) is a state in which the upper chamber and the lower chamber in the vacuum laminator are decompressed by a vacuum pump or the like, and (3) is an atmospheric pressure in the upper chamber. A state where the unvulcanized silicone rubber sheet is attached to the back sheet by pressing the diaphragm sheet through the protective sheet for a predetermined time, and (4) is released from the vacuum laminator chamber and the protective sheet is removed from the vacuum laminator chamber. The state which peels and obtains a 2nd laminated body is shown. It is an example of the process of sealing the solar cell matrix of the manufacturing method of the solar cell module which concerns on this invention, and is sectional drawing of the process using a vacuum laminator, (1) is between a 1st laminated body and a 2nd laminated body. (2) is a state where the upper and lower chambers in the vacuum laminator are decompressed by a vacuum pump or the like, and (3) is a diaphragm sheet where the upper chamber is returned to atmospheric pressure. In the state where the solar cell matrix is sealed by pressing for a predetermined time, (4) shows the state where the reduced pressure is released and the laminated body is taken out from the vacuum laminator chamber and sealed.

The method for manufacturing a solar cell module according to the present invention includes sealing a solar cell element matrix formed by connecting a plurality of solar cell elements interposed between transparent panels or between a transparent panel and a back sheet. In the solar cell module manufacturing method for manufacturing the solar cell module,
(Step 1) A step of preparing a first laminate in which an unvulcanized silicone rubber sheet made of a millable type silicone rubber composition is attached to one surface of a transparent panel at 10 ° C. to 50 ° C. under reduced pressure;
(Process 2) The process of preparing the 2nd laminated body which affixed unvulcanized silicone rubber sheet which consists of a millable type silicone rubber composition on one surface of a panel or a back sheet between 10 degreeC-50 degreeC under pressure reduction. When,
(Process 3) While arrange | positioning the said 1st laminated body and the 2nd laminated body with each other's silicone rubber sheet | seat surface facing each other, a solar cell matrix is arrange | positioned among them, and between 10 degreeC-50 degreeC in the state Depressurizing and pressing the first laminate and the second laminate to seal the solar cell matrix;
(Step 4) The above-mentioned sealed laminate is heated at 70 to 150 ° C. for 20 to 50 minutes to cure the silicone rubber sheet.

  Below, the suitable aspect of the manufacturing method of the solar cell module which concerns on this invention is demonstrated, referring drawings.

(First embodiment)
The manufacturing method of the solar cell module according to the present invention includes, as a first embodiment, a transparent panel in which the protective sheet on one side of the unvulcanized silicone rubber sheet made of the silicone rubber composition in Step 1 is attached. The step 2 is a step of attaching a protective sheet on one side of an unvulcanized silicone rubber sheet comprising the silicone rubber composition. It has the process of mounting on the one surface of a panel or a back sheet, and affixing by press at 10 degreeC-50 degreeC under pressure reduction, with attaching.

In this case, preferably, in the method for manufacturing a solar cell module according to the present embodiment, the solar cell element matrix interposed between the transparent panels or between the transparent panels and the back sheet is resin-sealed. In a method for manufacturing a solar cell module for manufacturing a solar cell module,
(I) (A) The following average composition formula (I)
R ¹ _a SiO _{(4-a) / 2} (I)
(In the formula, R ¹ represents the same or different unsubstituted or substituted monovalent hydrocarbon group, and a is a positive number of 1.95 to 2.05.)
100 parts by mass of an organopolysiloxane having at least two alkenyl groups in one molecule represented by
(B) 10 to 150 parts by mass of reinforcing silica having a specific surface area of 50 m ² / g or more,
(C) Curing agent (A) The pressure is reduced by placing the protective sheet on one side of an unvulcanized silicone rubber sheet made of a silicone rubber composition containing an effective amount for curing the component, on one side of the transparent panel. A step of applying by pressing at a lower 10 ° C. to 50 ° C .;
(Ii) Place the protective sheet on one side of the unvulcanized silicone rubber sheet made of the above-mentioned silicone rubber composition on one side of the panel or back sheet, and apply it by pressing at 10-50 ° C under reduced pressure. Attaching process,
(Iii) A solar cell element matrix is placed on the transparent rubber panel or the silicone rubber sheet of the panel or back sheet, the transparent panel and the panel or back sheet are overlapped with the silicone rubber sheet inside, and the pressure is reduced to 10 ° C. Pressing at ~ 50 ° C to seal the solar cell element matrix;
(IV) including the step of placing the sealed laminate in a heating furnace and heating between 70 ° C. and 150 ° C. for 20 to 50 minutes to cure the silicone rubber sheet. The above process will be further described in detail.

(I) Step of Preparing First Laminate As shown in FIG. 1, an unvulcanized silicone rubber sheet 3a made of a millable type silicone rubber composition is attached to one side of a transparent panel 1 and a protective sheet 4a is attached to one side. It is the process of attaching between 10 degreeC-50 degreeC under pressure reduction with attaching.
In FIG. 1, 10 is a vacuum laminator, 11 is a diaphragm sheet, and 12 is a plate. In this case, the diaphragm sheet 11 is in close contact with the upper inner wall surface of the vacuum laminator 10 due to the reduced pressure from the upper opening.
Here, the transparent panel is a transparent member on the side on which sunlight is incident (light receiving surface side), and is also referred to as a light receiving surface panel, and is used outdoors such as transparency, weather resistance, and impact resistance. A member having long-term reliability performance is required. For example, white plate tempered glass, acrylic resin, fluororesin or polycarbonate resin can be mentioned, and white plate tempered glass having a thickness of about 3 to 5 mm is particularly preferable.

  The unvulcanized silicone rubber sheet is preferably composed of the following millable type silicone rubber composition.

That is, the component (A) is an organopolysiloxane having at least two alkenyl groups in one molecule represented by the following average composition formula (I) and having a degree of polymerization of 100 or more.
R ¹ _a SiO _{(4-a) / 2} (I)
(In the formula, R ¹ represents the same or different unsubstituted or substituted monovalent hydrocarbon group, and a is a positive number of 1.95 to 2.05.)

In the above average composition formula (I), R ¹ represents the same or different unsubstituted or substituted monovalent hydrocarbon group, usually having 1 to 12 carbon atoms, particularly preferably having 1 to 8 carbon atoms. Are alkyl groups such as methyl, ethyl, propyl, butyl, hexyl and octyl, cycloalkyl such as cyclopentyl and cyclohexyl, alkenyl such as vinyl, allyl and propenyl, cyclo An aryl group such as an alkenyl group, a phenyl group or a tolyl group, an aralkyl group such as a benzyl group or a 2-phenylethyl group, or a part or all of the hydrogen atoms of these groups is a halogen such as a fluorine atom, a chlorine atom or a bromine atom A group substituted with an atom or a cyano group, and the like, and a methyl group, a vinyl group, a phenyl group, and a trifluoropropyl group are preferable. Group is preferred.

Specifically, the repeating structure of diorganosiloxane units (R ¹ ₂ SiO _2/2 , R ¹ is the same as described above, the same applies hereinafter) constituting the main chain of the organopolysiloxane consists of repeating dimethylsiloxane units only. Or a diphenylsiloxane unit having a phenyl group, a vinyl group, a 3,3,3-trifluoropropyl group or the like as a substituent as a part of a dimethylpolysiloxane structure composed of repeating dimethylsiloxane units constituting the main chain In addition, those in which a diorganosiloxane unit such as a methylphenylsiloxane unit, a methylvinylsiloxane unit, or a methyl-3,3,3-trifluoropropylsiloxane unit is introduced are preferable.

The both ends of the molecular chain are, for example, triorganosiloxy groups (R ¹ ₃ SiO _1/2 ) such as trimethylsiloxy group, dimethylphenylsiloxy group, vinyldimethylsiloxy group, divinylmethylsiloxy group, trivinylsiloxy group, hydroxy It is preferably blocked with a hydroxydiorganosiloxy group (R ¹ ₂ (HO) SiO _1/2 ) such as a dimethylsiloxy group. Among these, a trivinylsiloxy group is particularly preferable because of its high reactivity.

In particular, the organopolysiloxane as the component (A) needs to have an alkenyl group bonded to two or more silicon atoms in one molecule. Usually, those having 2 to 50, especially 2 to 20 alkenyl groups are preferred, and those having a vinyl group are particularly preferred. In this case, it is preferable that 0.01-20 mol%, especially 0.02-10 mol% in all R < ¹ > is an alkenyl group. The alkenyl group may be bonded to the silicon atom at the molecular chain end, or may be bonded to the silicon atom in the middle of the molecular chain (molecular chain non-terminal), or both. It is preferably bonded to the silicon atom at the end of the molecular chain.

Moreover, a is a positive number of 1.95 to 2.05, preferably 1.98 to 2.02, more preferably 1.99 to 2.01. The total R ¹ in 90 mol% or more, preferably 95 mol% or more, still more preferably all the R ¹ is an alkyl group other than an alkenyl group, particularly a methyl group.

  Such an organopolysiloxane can be obtained by, for example, hydrolyzing and condensing one or more types of organohalogenosilanes, or by converting cyclic polysiloxanes (siloxane trimers, tetramers, etc.) to alkaline or acidic. It can obtain by ring-opening polymerization using the catalyst of. These are basically linear diorganopolysiloxanes, but the component (A) may be a mixture of two or more different molecular weights (degree of polymerization) and molecular structures.

  The degree of polymerization of the organopolysiloxane is preferably 100 or more (usually 100 to 100,000), more preferably 2,000 to 50,000, particularly preferably 3,000 to 20,000, and room temperature ( At 25 ° C., it is preferably a so-called raw rubber (non-liquid) that does not have self-fluidity. If the degree of polymerization is too small, problems such as roll adhesion may occur when the compound is used, and roll workability may be reduced. In addition, this polymerization degree can be normally measured as a weight average polymerization degree in terms of standard polystyrene by gel permeation chromatography (GPC) analysis using toluene as a developing solvent (hereinafter the same).

  Component (B), reinforcing silica, is added to obtain a silicone rubber composition having excellent mechanical strength and excellent transparency.

In order to have excellent mechanical strength, the specific surface area (BET adsorption method) needs to be 50 m ² / g or more, preferably 100 to 450 m ² / g, more preferably 100 to 300 m ² / g. It is. When the specific surface area is less than 50 m ² / g, the mechanical strength of the cured product is lowered. Further, in particular, in order to give excellent transparency at a wavelength of 300 nm or less as the cured silicone rubber, the specific surface area is preferably 200 m ² / g or more, more preferably 250 m ² / g or more. Thereby, for example, the 2 mm-thick cured product sheet of the silicone rubber composition has a total light transmittance of 90% or more and a haze value of 10 or less.

  Examples of such reinforcing silica include fumed silica (dry silica or fumed silica), precipitated silica (wet silica), and the like, and these surfaces have been hydrophobized with chlorosilane, hexamethyldisilazane, or the like. Those are also preferably used. Among these, fumed silica excellent in dynamic fatigue characteristics is preferable. (B) A component may be used individually by 1 type, or may use 2 or more types together.

  As the reinforcing silica of component (B), commercially available products can be used. For example, Aerosil series such as Aerosil 130, Aerosil 200, Aerosil 300, Aerosil R-812, Aerosil R-972, Aerosil R-974 (Japan) Aerosil Co., Ltd.), Cabosil MS-5, MS-7 (Cabot), Leoroseal QS-102, 103, MT-10 (Tokuyama), etc. , Hydrophilic or hydrophobic fumed silica, Toxeal US-F (manufactured by Tokuyama), NIPSIL-SS, NIPSIL-LP (manufactured by Nippon Silica), etc. Examples include precipitated silica.

  The blending amount of the reinforcing silica as the component (B) is 10 to 150 parts by weight, preferably 50 to 120 parts by weight, more preferably 70 to 100 parts by weight with respect to 100 parts by weight of the organopolysiloxane as the component (A). 100 parts by mass. When the blending amount of the component (B) is too small, the reinforcing effect cannot be obtained and the transparency after curing the silicone rubber compound is lowered. When the amount is too large, it becomes difficult to disperse the silica in the silicone polymer, and at the same time, the workability is deteriorated and the mechanical strength is also lowered.

  The curing agent for component (C) is not particularly limited as long as it can cure the component (A). Generally, (a) addition reaction (hydrosilylation reaction) known as a rubber curing agent. ) Type curing agent, that is, a combination of an organohydrogenpolysiloxane (crosslinking agent) and a hydrosilylation reaction catalyst, or (b) an organic peroxide.

The organohydrogenpolysiloxane as a crosslinking agent in the above (a) addition reaction (hydrosilylation reaction) contains hydrogen atoms (SiH groups) bonded to at least two silicon atoms in one molecule. Conventionally known organohydrogenpolysiloxane represented by the composition formula (II) is applicable.
R ² _b H _c SiO _{(4-bc) / 2} (II)
Wherein R ² represents the same or different unsubstituted or substituted monovalent hydrocarbon group, b is 0.7 to 2.1, c is 0.01 to 1.0, and b + c is 0.8. It is a positive number of ~ 3.0.)

Here, R ² is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 8 carbon atoms, and preferably has no aliphatic unsaturated bond. Specific examples include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, an alkyl group such as a pentyl group and a hexyl group, a cycloalkyl group such as a cyclohexyl group, and a phenyl group. At least a part of hydrogen atoms of the monovalent hydrocarbon group such as an aryl group, an aralkyl group such as a benzyl group, an unsubstituted monovalent hydrocarbon group, a 3,3,3-trifluoropropyl group, a cyanomethyl group, etc. is fluorine. A substituted monovalent hydrocarbon group such as a substituted alkyl group substituted with a halogen atom such as an atom, chlorine atom or bromine atom or a cyano group. b is 0.7 to 2.1, c is 0.01 to 1.0, and b + c is 0.8 to 3.0, preferably b is 0.8 to 2.0, and c is 0.10 to 1 0.0, more preferably 0.18 to 1.0, still more preferably 0.2 to 1.0, and b + c is a positive number satisfying 1.0 to 2.5.

  The molecular structure of the organohydrogenpolysiloxane may be any of a linear, cyclic, branched, and three-dimensional network structure. In this case, the number of silicon atoms in one molecule (or the degree of polymerization) is preferably 2 to 300, particularly 4 to 200 at room temperature (25 ° C.). The hydrogen atom (SiH group) bonded to the silicon atom may be at the end of the molecular chain, at the side chain (in the middle of the molecular chain), or both, and at least two (usually normal) 2 to 300), preferably 3 or more (for example, 3 to 200), more preferably about 4 to 150.

Examples of the organohydrogenpolysiloxane include 1,1,3,3-tetramethyldisiloxane, 1,3,5,7-tetramethylcyclotetrasiloxane, methylhydrogencyclopolysiloxane, methylhydrogensiloxane and dimethyl. Siloxane cyclic copolymer, tris (dimethylhydrogensiloxy) methylsilane, tris (dimethylhydrogensiloxy) phenylsilane, trimethylsiloxy group-blocked methylhydrogenpolysiloxane at both ends, trimethylsiloxy group-blocked dimethylsiloxane / methylhydrogensiloxane at both ends Copolymers, dimethylpolysiloxane blocked with dimethylhydrogensiloxy groups at both ends, dimethylsiloxane / methylhydrogenblocked with dimethylhydrogensiloxy groups at both ends Siloxane copolymer, trimethylsiloxy group-capped methylhydrogensiloxane / diphenylsiloxane copolymer, trimethylsiloxy group-capped methylhydrogensiloxane / diphenylsiloxane / dimethylsiloxane copolymer, cyclic methylhydrogenpolysiloxane, Cyclic methylhydrogensiloxane / dimethylsiloxane copolymer, cyclic methylhydrogensiloxane / diphenylsiloxane / dimethylsiloxane copolymer, a copolymer comprising (CH ₃ ) ₂ HSiO _1/2 units and SiO _4/2 units, In the copolymer or the like comprising (CH ₃ ) ₂ HSiO _1/2 unit, SiO _4/2 unit and (C ₆ H ₅ ) SiO _3/2 unit, and the above exemplified compounds, part or all of methyl groups Other ethyl groups such as ethyl group and propyl group And those substituted with an aryl group such as a ruthenium group. Moreover, as such organohydrogenpolysiloxane, the compound of the following structural formula can be illustrated specifically.

（式中、ｋは２〜１０の整数、ｓ及びｔはそれぞれ０〜１０の整数である。）

(In the formula, k is an integer of 2 to 10, and s and t are each an integer of 0 to 10.)

  The organohydrogenpolysiloxane preferably has a viscosity at 25 ° C. of 0.5 to 10,000 mPa · s, particularly 1 to 300 mPa · s. The viscosity can be measured with a rotational viscometer.

  Further, this organohydrogenpolysiloxane has a hydrogen atom bonded to a silicon atom in the organohydrogenpolysiloxane with respect to an aliphatic unsaturated group such as an alkenyl group bonded to the silicon atom in the component (A) (that is, SiH group). ) Molar ratio (SiH group / aliphatic unsaturated group) is 0.5 to 10 mol / mol, preferably 0.8 to 6 mol / mol, more preferably 1 to 5 mol / mol. It is desirable. If it is less than 0.5 mol / mol, crosslinking may not be sufficient, and sufficient mechanical strength may not be obtained. If it exceeds 10 mol / mol, physical properties after curing will be deteriorated, particularly heat resistance and resistance. The compression set may be significantly degraded.

  The compounding amount of the organohydrogenpolysiloxane is an effective amount for curing the organopolysiloxane of the component (A), and is 0.1 to 30 parts by mass with respect to 100 parts by mass of the organopolysiloxane of the component (A). Is preferable, more preferably 0.1 to 10 parts by mass, and still more preferably 0.3 to 10 parts by mass.

  The hydrosilylation reaction catalyst used for the crosslinking reaction in the above (a) addition reaction (hydrosilylation reaction) is an aliphatic unsaturated group (such as an alkenyl group) in the component (A) and the organo as a crosslinking agent. It is a catalyst for addition reaction of silicon atom-bonded hydrogen atoms (SiH groups) in hydrogen polysiloxane. Examples of the hydrosilylation reaction catalyst include a platinum group metal catalyst, which includes a platinum group metal element and a compound thereof, and conventionally known catalysts for addition reaction curable silicone rubber compositions can be used. For example, particulate platinum metal adsorbed on a carrier such as silica, alumina or silica gel, platinum chloride, chloroplatinic acid, chloroplatinic acid hexahydrate alcohol solution, palladium catalyst, rhodium catalyst, etc. Platinum or platinum compounds are preferred.

  The addition amount of the hydrosilylation reaction catalyst may be a so-called catalyst amount that can promote the addition reaction, and is usually used in the range of 1 ppm to 1% by mass in terms of platinum-based metal mass with respect to component (A). However, the range of 10 to 500 ppm is preferable. If the addition amount is less than 1 ppm, the addition reaction may not be sufficiently promoted and curing may be insufficient. On the other hand, if it exceeds 1% by mass, there is little influence on the reactivity even if it is added more than this. It may be an economy.

  In addition to the above catalyst, an addition crosslinking controller may be used for the purpose of adjusting the curing rate. Specific examples include ethynylcyclohexanol and tetramethyltetravinylcyclotetrasiloxane.

  On the other hand, as (b) organic peroxide, for example, benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, p-methylbenzoyl peroxide, o-methylbenzoyl peroxide, 2,4-dicumyl peroxide, 2,5-dimethyl-bis (2,5-t-butylperoxy) hexane, di-t-butylperoxide, t-butylperbenzoate, 1,6-hexanediol-bis-t-butylperoxycarbonate, etc. Is mentioned.

  The addition amount of the organic peroxide is preferably 0.1 to 15 parts by mass, particularly preferably 0.2 to 10 parts by mass with respect to 100 parts by mass of the component (A). If the addition amount is too small, the crosslinking reaction does not proceed sufficiently, which may result in deterioration of physical properties such as a decrease in hardness, insufficient rubber strength, an increase in compression set, and too much is not preferable in terms of cost, but also a curing agent. In some cases, a large amount of decomposition products of the above may occur, resulting in deterioration of physical properties such as an increase in compression set and discoloration of the obtained sheet.

  Moreover, in order to improve adhesiveness with a transparent panel and a panel or a back sheet, you may add a silane coupling agent by a conventional method.

  A silicone rubber composition is obtained by kneading predetermined amounts of the components (A), (B) and (C) with a two-roll, kneader, Banbury mixer or the like.

  The plasticity (in accordance with JIS K6249) of the silicone rubber composition thus prepared is 150 or more and 1,000 or less, preferably 200 or more and 800 or less, and more preferably 250 or more and 600 or less. When the plasticity is less than 150, the adhesiveness of the sheet increases and the workability is inferior, and it becomes difficult to work even when embossing is performed in the subsequent steps and the embossed sheet is peeled off. And it becomes difficult to maintain the uneven | corrugated shape of the emboss structure provided to the silicone rubber sheet surface. On the other hand, if the plasticity exceeds 1,000, the sheet itself becomes brittle and it may be difficult to emboss.

  Furthermore, the silicone rubber composition can be formed into a sheet by a conventional method such as a calendar molding method, an injection method, or a press method. At this time, the silicone rubber sheet is preferably formed with a thickness of 0.3 mm or more and 2.0 mm or less, and more preferably 0.3 mm or more and 1.0 mm or less. If it is thinner than 0.3 mm, the sheet may be damaged when embossed in the next process, and may be damaged. If it is thicker than 2.0 mm, molding may be difficult, especially with a calendar molding method, and the cost may be inferior. There is. As described above, an unvulcanized silicone rubber sheet having an adhesive property and a flat surface is obtained.

  In order to prevent damage or contamination of the surface of the obtained silicone rubber sheet 3a, it is preferable to protect the surface of the silicone rubber sheet 3a by attaching a protective sheet 4a to at least one surface. The material of the protective sheet used in this case is not particularly limited as long as it has good releasability from the silicone rubber sheet. For example, an embossed sheet made of polyethylene can be used. Moreover, it is preferable that the thickness of a protective sheet is 0.08 mm or more and 0.3 mm or less. If it is thinner than 0.08 mm, it may be difficult to peel it off from the silicone rubber sheet, and if it is thicker than 0.3 mm, the cost becomes high.

  On the surface of the transparent panel 1, the surface on which the protective sheet 4a is not applied is placed on the transparent panel while the silicone rubber sheet 3a is adhered to the protective sheet 4a on one side [FIG. 1 (1)]. Next, for example, using a laminating apparatus such as a vacuum laminator 10 under reduced pressure by a conventional method [FIG. 1 (2)], the diaphragm sheet 11 between 10 ° C. and 50 ° C. for 3 minutes to 10 minutes through the protective sheet 4a The silicone rubber sheet 3a is stuck on the transparent panel 1 by pressing for a minute [FIG. 1 (3)]. In addition, the arrow in a figure shows the deaeration direction. After pasting, the protective sheet is peeled off to obtain the first laminate 20 [FIG. 1 (4)]. In addition, the time required for pressure reduction when the silicone rubber sheet is attached is 2 minutes to 10 minutes, and the degree of pressure reduction is preferably between 50 Pa and 200 Pa, and more preferably 70 Pa to 150 Pa. If the degree of vacuum is higher than 50 Pa, it may take too much time to reduce the pressure and work efficiency may be inferior. On the other hand, if the degree of vacuum is lower than 200 Pa, bubbles may remain between the silicone rubber sheet and the transparent panel. . On the other hand, the temperature range is preferably between 10 ° C. and 50 ° C., more preferably in the range of 20 ° C. to 40 ° C. near normal temperature. When the temperature is lower than 10 ° C., cooling is necessary particularly in summer, and there is a possibility that the operation cost may be increased. When the temperature is higher than 50 ° C., the silicone rubber sheet may be partially cured.

  Moreover, as a vacuum laminator apparatus, the laminator apparatus for production of a general-purpose solar cell module having two adjacent decompression tanks partitioned by a flexible film body can be adopted.

(Ii) Step of Preparing Second Laminate As shown in FIG. 2, an unvulcanized silicone rubber sheet 3b made of a millable type silicone rubber composition is provided on one side of the panel or back sheet 2, and a protective sheet 4b on one side. It is the process of affixing between 10 degreeC-50 degreeC under pressure reduction, having affixed. The same components as those in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted.

  Here, the panel or the back sheet is arranged to face the transparent panel, and the panel is required to efficiently dissipate the temperature of the solar cell element, and the material is a glass material or a synthetic resin. A material, a metal material, or those composite members are mentioned. Examples of the glass material include blue plate glass, white plate glass, or tempered glass, and examples of the synthetic resin material include acrylic resin, polycarbonate (PC) resin, polyethylene terephthalate (PET) resin, and epoxy resin. In addition, examples of the metal material include copper, aluminum, and iron, and examples of the composite member include a synthetic resin carrying a material having high thermal conductivity such as silica, titanium oxide, alumina, and aluminum nitride. . In addition, when this panel is a panel on the opposite side of sunlight incidence, by using a transparent member together with the panel on which sunlight is incident, direct sunlight and part of the scattered light is absorbed by sunlight. Can be transmitted to the opposite side, for example, when installed on grassland, etc., by irradiating part of the sunlight to the part opposite to the incident surface of the solar cell module, that is, the part that would originally be shaded It promotes the growth of plants and can be used for grazing livestock.

  As the back sheet, for example, a fluororesin film such as an ETFE (ethylene-tetrafluoroethylene copolymer) film, a PVF (polyvinyl fluoride) film, or a laminated sheet or PET in which an aluminum foil or PET is sandwiched between PVF sheets. A sheet coated with a fluororesin paint can be used.

  In the same manner as in (i), on one surface of the panel or back sheet 2, the surface on which the protective sheet is not adhered is left on the panel or back sheet while the silicone rubber sheet 3b is adhered to the protective sheet 4b on one side. Place [Fig. 2 (1)]. Next, using a laminating apparatus such as a vacuum laminator 10, for example, under reduced pressure by a conventional method [FIG. 1 (2)], the diaphragm sheet 11 between 10 ° C. and 50 ° C. for 3 minutes to 10 minutes through the protective sheet 4b The silicone rubber sheet 3b is stuck on the panel or back sheet 2 by pressing for a minute [FIG. 2 (3)]. After pasting, the protective sheet is peeled off to obtain the second laminate 30 [FIG. 2 (4)]. In addition, the time required for pressure reduction when the silicone rubber sheet is attached is 2 minutes to 10 minutes, and the degree of pressure reduction is preferably between 50 Pa and 200 Pa, and more preferably 70 Pa to 150 Pa. If the degree of vacuum is higher than 50 Pa, it may take too much time to reduce the pressure and work efficiency may be inferior. On the other hand, if the degree of vacuum is lower than 200 Pa, bubbles may remain between the silicone rubber sheet and the transparent panel. . On the other hand, the temperature range is preferably between 10 ° C. and 50 ° C., more preferably in the range of 20 ° C. to 40 ° C. near normal temperature. When the temperature is lower than 10 ° C., cooling is necessary particularly in summer, and there is a possibility that the operation cost may be increased. When the temperature is higher than 50 ° C., the silicone rubber sheet may be partially cured.

(Iii) Step of sealing the solar cell matrix As shown in FIG. 3, the solar cell element matrix 5 is disposed on the first laminate 20 in which the silicone rubber sheet 3a is bonded to the transparent panel 1, and the panel Alternatively, the second laminated body 30 with the silicone rubber sheet 3b attached to the back sheet 2 is sandwiched between the solar cell element matrix 5 with the silicone rubber sheets 3a and 3b inside, and the light receiving surface thereof facing the transparent panel. This is a step of sealing the solar cell element matrix by overlapping and pressing at 10 to 50 ° C. under reduced pressure.

  Here, the solar cell element 6 is a solar cell fabricated using one or two types of silicon materials (silicon substrate) selected from single crystal silicon or polycrystalline silicon, and the solar cell element matrix is In general, 4 to 60 solar cells are arranged in a state (matrix shape) arranged in a two-dimensional vertical and horizontal two-dimensional direction and are electrically connected in series with an interconnector 7 such as a tab wire. It is. In addition, when a solar cell element is a double-sided light-receiving type, not only a transparent panel but the panel or back sheet arrange | positioned facing a transparent panel shall also be transparent.

As described above, the first laminate 20, the solar cell matrix 5 and the second laminate 30 are laminated [FIGS. 3 (1) and (2)], and pressed under reduced pressure at 10 ° C. to 50 ° C. for 3 minutes to 10 minutes. Then, the solar cell element matrix 5 is sealed [FIG. 3 (3)]. In addition, the time required for the pressure reduction at the time of sealing is 2 minutes to 10 minutes, and the degree of pressure reduction is preferably between 50 Pa to 200 Pa, and more preferably 70 Pa to 150 Pa. If the degree of vacuum is higher than 50 Pa, it may take too much time to reduce the pressure and work efficiency may be inferior. On the other hand, if the degree of vacuum is lower than 200 Pa, the silicone rubber sheet 3b or between the silicone rubber sheet 3a and the transparent panel 1 Air bubbles may remain between the panels or the backsheet 2. On the other hand, the temperature range is preferably between 10 ° C. and 50 ° C., more preferably in the range of 20 ° C. to 40 ° C. near normal temperature. When the temperature is lower than 10 ° C., cooling is necessary particularly in summer, and there is a possibility that the operation cost may be increased. When the temperature is higher than 50 ° C., the silicone rubber sheet may be partially cured.
In this way, a composite laminate 40 is obtained [FIG. 3 (4)].

  In general, for example, when EVA (ethylene-vinyl acetate copolymer) is used as a sealing material, there is a sealing process called a standard cure process or a first cure process. In this process, a sealing device such as a vacuum laminator is heated to 100 ° C. to 160 ° C., and the laminate is sealed under reduced pressure for 10 minutes to 20 minutes. In particular, in the standard cure process, the sealing material is sufficiently cross-linked by further heating in a heating furnace after the sealing step.

  According to the method for manufacturing a solar cell module of the present invention, the vacuum laminator for sealing can be used without heating. That is, it is possible to reduce the cost of utilities required for heating the vacuum laminator and the cost for compensating for aging deterioration of the apparatus, and it is possible to improve the working environment for handling the heated vacuum laminator.

(IV) Step of curing the silicone rubber sheet by heating the composite laminate with the solar cell element matrix sealed between 70 ° C. and 150 ° C. for 20 minutes to 50 minutes. Next, the solar cell element matrix is sealed. The stopped laminate is heated on a heating furnace or a hot plate of the vacuum laminator between 70 ° C. and 150 ° C. for 20 to 50 minutes to accelerate the vulcanization reaction and cure the silicone rubber sheets 3a and 3b. . At this time, if the curing temperature is lower than 70 ° C., there is a possibility that the vulcanization reaction does not proceed sufficiently, the vulcanization reaction rate higher than 150 ° C. increases, the silicone rubber sheet cures faster, There is a possibility that the seal cannot be completely sealed at a portion where there is a step in the periphery of the interconnector.

Finally, a frame member is attached to the outer peripheral end portion (frame end portion) of the transparent panel and the panel or back sheet after sealing to complete the solar cell module.
The frame member is preferably made of an aluminum alloy, stainless steel, or the like that has excellent strength against impact, wind pressure, or snow accumulation, has weather resistance, and is lightweight. A frame member molded with these materials is mounted so as to surround the outer periphery of the panel sandwiching the solar cell elements, and fixed with screws or the like.
The solar cell module manufactured as described above has high efficiency and long-term reliability because the solar cell element matrix is held on a flat transparent panel and a panel or back sheet via a cured silicone rubber. It will be a thing. Moreover, according to the present invention, mass production of such a high-performance solar cell module is facilitated.

(Second Embodiment)
As a second embodiment, the method for producing a solar cell module according to the present invention is a non-added process comprising a millable type silicone rubber composition in the step of preparing the second laminate in step (ii) shown in FIG. By preparing a backsheet-silicone rubber composite in which sulfur silicone rubber is topped at 10 ° C. to 50 ° C. according to a conventional method on one side of the backsheet in advance, the backsheet is manufactured at the solar cell module manufacturing site. The process of sticking the silicone rubber sheet on can be omitted, and the process cost can be reduced. In this case, as the back sheet to be used, a fluorine resin film such as an ETFE (ethylene-tetrafluoroethylene copolymer) film or a PVF (polyvinyl fluoride) film, or an aluminum foil or PET is used as a PVF sheet in the same manner as described above. A laminated sheet sandwiched between two layers or a sheet coated with a fluororesin coating on PET can be used. That is, by unrolling the unvulcanized silicone rubber made of the above silicone composition with a calender roll at 10 ° C. to 50 ° C. to form a sheet, and at the same time, performing “topping processing” to be bonded onto the back sheet as the base material The process of sticking the silicone rubber sheet to the back sheet at the solar cell module manufacturing site can be omitted. At this time, the silicone rubber sheet is preferably formed with a thickness of 0.3 mm or more and 2.0 mm or less, and more preferably 0.3 mm or more and 1.0 mm or less. If it is thinner than 0.3 mm, the sheet may be damaged when embossed in the next process, and may be damaged. If it is thicker than 2.0 mm, molding may be difficult, especially with a calendar molding method, and the cost may be inferior. There is. Moreover, it is preferable to affix the protective sheet for preventing a stain | pollution | contamination on the silicone rubber surface of the backsheet-silicone rubber composite which performed the topping process. The material of the protective sheet used in this case is not particularly limited as long as it has a good releasability from the silicone rubber sheet as described above. For example, an embossed sheet made of polyethylene can be used. Moreover, it is preferable that the thickness of a protective sheet is 0.08 mm or more and 0.3 mm or less. If it is thinner than 0.08 mm, it may be difficult to peel it off from the silicone rubber sheet, and if it is thicker than 0.3 mm, the cost becomes high.

The second laminate obtained as described above is sealed with the solar cell matrix in the same procedure as in (iii) and (iv), and after the silicone rubber sheet is cured, the frame member is attached. A solar cell module is completed.
The solar cell module manufactured as described above has high efficiency and long-term reliability because the solar cell element matrix is held on a flat transparent panel and a panel or back sheet via a cured silicone rubber. It will be a thing. Moreover, according to the present invention, by preparing the backsheet-silicone rubber composite, the step of attaching using a vacuum laminator can be omitted, so that the work efficiency can be improved. The mass production of solar cell modules becomes easy.

  EXAMPLES Hereinafter, although an Example, a comparative example, and a reference example are shown and this invention is demonstrated concretely, this invention is not restrict | limited to the following Example. In addition, a part shows a mass part by the following example. Moreover, room temperature shows 25 degreeC. Moreover, a mass average polymerization degree is a polystyrene conversion value in a gel permeation chromatography (GPC) analysis.

[Example 1]
A solar cell module was produced under the following conditions.
First, 100 parts of an organopolysiloxane having 99.825 mol% of dimethylsiloxane units, 0.15 mol% of methyl vinyl siloxane units and 0.025 mol% of dimethyl vinyl siloxane units and having an average degree of polymerization of about 8,000, BET 80 parts of dry silica (Aerosil 200 (manufactured by Nippon Aerosil Co., Ltd.)) with a specific surface area of 200 m ² / g, 5 parts of dimethylpolysiloxane having silanol groups at both ends and a viscosity of 29 mPa · s (25 ° C.) Was blended with a kneader and heat treated at 180 ° C. for 2 hours to produce a base rubber compound.

  Next, 0.5 parts of C-25A (platinum catalyst) and 2.0 parts of C-25B (organohydrogenpolysiloxane) (both manufactured by Shin-Etsu Chemical Co., Ltd.) were added and mixed in a two-roll mill as addition curing agents. A 5 mm thick silicone rubber sheet was produced. In addition, it was 430 when the plasticity degree of the obtained silicone rubber composition was measured according to JIS K6249.

  Next, the obtained 5 mm thick silicone rubber sheet was molded into a 0.8 mm thick silicone rubber sheet at room temperature using a Nippon Roll Co., Ltd. calender molding machine, and then both sides of the silicone rubber sheet were also treated at room temperature. Further, a protective sheet (Ishijima Chemical Industry Co., Ltd., embossed NEF type; thickness 0.15 mm) was embossed on both sides of the silicone rubber sheet by pressing the embossed surface with a rubber roller (hereinafter referred to as this silicone). The rubber sheet is called “silicone rubber sheet with double-sided protective sheet”).

  Next, after peeling off the protective sheet on one side of the silicone rubber sheet with double-sided protective sheet, the peeled surface is a white panel tempered glass substrate having a thickness of 3.2 mm and a vertical and horizontal dimension of 340 mm × 360 mm which is a transparent panel on the light receiving surface side. Hereinafter, it was placed on a glass substrate.

  This is set in a vacuum laminator with the glass substrate facing down (state shown in FIG. 1 (1)), and after decompression at 30 ° C. for 2 minutes (state shown in FIG. 1 (2)), the degree of decompression in the lower chamber Was confirmed to be 100 Pa or less, and the upper chamber was pressed to atmospheric pressure for 3 minutes (the state shown in FIG. 1 (3)). After that, the decompression was released, and a laminated body in which a silicone rubber sheet with a protective sheet on one side was stuck to a glass substrate without a gap was obtained, and the protective sheet on the upper surface was further peeled to obtain a first laminated body (Fig. 1 (4) state).

  Next, after peeling off the protective sheet on one side of the silicone rubber sheet with the double-sided protective sheet in the same manner as described above, the peeled surface was formed as a back sheet PTD250 (Tedlar-PET- It was placed on a Tedlar laminated type backsheet (hereinafter, backsheet).

  This is set in a vacuum laminator with the back sheet facing down (state shown in FIG. 2 (1)), after decompression at 30 ° C. for 2 minutes (state shown in FIG. 2 (2)), the degree of decompression in the lower chamber Was confirmed to be 100 Pa or less, and the upper chamber was pressed to atmospheric pressure for 3 minutes (the state shown in FIG. 2 (3)). After that, the decompression was released, and a laminated body in which a silicone rubber sheet with a protective sheet on one side was attached to the back sheet without a gap was obtained, and the protective sheet on the upper surface was further peeled to obtain a second laminated body (Fig. 2 (4) state).

  Next, as shown in FIG. 3 (1), a total of four single-crystal silicon solar cells in which solar cell elements are connected in two rows and two columns in the vertical and horizontal directions on the first laminate with the glass substrate side down. The element matrix was placed / laminated, and the second laminate with the silicone rubber sheet face down was further placed / laminated, set in a vacuum laminator, and then decompressed at 30 ° C. for 2 minutes (FIG. 3 (2 The state shown in FIG. 3 (3)) was confirmed by confirming that the degree of decompression of the lower chamber was 100 Pa or less, and pressing the upper chamber at atmospheric pressure for 3 minutes (the state shown in FIG. 3 (3)). Thereafter, the decompression was released to obtain a laminate in which the solar cell matrix was sealed (the state shown in FIG. 3 (4)).

  This was placed in a heating furnace heated to 130 ° C. for 30 minutes to cure the silicone rubber sheet, thereby producing a solar cell module A.

[Example 2]: Method of using topped sheet as second laminate The same procedure as in Example 1 was conducted except that a backsheet-silicone rubber composite was used as the second laminate in Example 1. The backsheet-silicone rubber composite was prepared by subjecting the silicone rubber composition obtained in Example 1 to 30 ° C. by a calendering method by a conventional method using a back sheet PTD250 manufactured by MPackaging Co., Ltd. having a width of 1,000 mm as a base material. The silicone rubber composition was obtained by topping the back sheet with a thickness of 0.8 mm, and pressing the protective sheet with a roller onto the silicone sheet surface. This was cut into a vertical and horizontal dimension of 340 mm × 360 mm to obtain a second laminate. This was placed and laminated in the same manner as in Example 1 and then vacuum laminated at 30 ° C.
This was placed in a heating furnace heated to 130 ° C. for 30 minutes to cure the silicone rubber sheet, thereby producing a solar cell module B.

[Comparative Example 1]: Method of Laminating Without Using the Second Laminate Same as Example 1 except that in Example 1, the second laminate in which the silicone rubber sheet was previously attached to the back sheet without any gap was not used. Went to. In other words, four straight single-crystal silicon solar cell matrixes are placed and laminated on the first laminated body with the glass substrate side down, and then the protective sheets on both sides of the silicone rubber sheet with the double-sided protective sheet are peeled off. Then, a silicone rubber sheet was placed / laminated on the solar cell element matrix, and a back sheet was further placed / laminated, followed by vacuum lamination at 30 ° C.
This was placed in a heating furnace heated to 130 ° C. for 30 minutes to cure the silicone rubber sheet, thereby producing a solar cell module C.

[Comparative Example 2]: Method of Laminating Without Using First Laminate In Example 1, the same procedure as in Example 1 is used except that the first laminated body in which the silicone rubber sheet is pasted on the glass substrate without gaps is not used. Went to. That is, on the glass substrate, the protective sheets on both sides of the double-sided protective sheet-attached silicone rubber sheet are peeled and placed and stacked, and then a four-line single crystal silicon solar cell element matrix is placed and stacked. Next, after mounting and laminating a second laminate in which a silicone sheet similar to that in Example 1 was previously bonded to a backsheet, vacuum lamination was performed at 30 ° C.
This was placed in a heating furnace heated to 130 ° C. for 30 minutes to cure the silicone rubber sheet, thereby producing a solar cell module D.

[Comparative Example 3]: In the step of obtaining the first laminated body, a laminated body obtained by a method in which a silicone sheet is pressure-bonded to a glass substrate using a film laminator instead of a vacuum laminator, and a top laminated sheet are obtained as a second laminated body. In Example 2, instead of using the first laminate produced using a vacuum laminator, a laminate obtained by a method of pressure bonding a silicone sheet to a glass substrate using a roll laminator was used, The same operation as in Example 2 was performed. That is, after peeling off the protective sheet on one side of the silicone rubber sheet with double-sided protective sheet, the peeled surface was placed on a glass substrate having a thickness of 3.2 mm and a vertical and horizontal dimension of 340 mm × 360 mm, which is a transparent panel on the light receiving surface side. Next, with the glass substrate facing down, set on a film laminator (roll width = 1,100 mm) manufactured by MCK Co., Ltd., sandwiched between two upper and lower feed rolls, a gap between upper and lower rolls = 3.5 mm, roll A laminated body was obtained by pressure-bonding a silicone rubber sheet to a glass substrate under the condition of pressure = 0.4 MPa. Using this laminate and the backsheet-silicone rubber composite used in Example 2 as the second laminate, this was placed and laminated in the same manner as in Example 2, and then vacuum laminated at 30 ° C. went.
This was placed in a heating furnace heated to 130 ° C. for 30 minutes to cure the silicone rubber sheet, thereby producing a solar cell module E.

[Comparative Example 4]: Method of laminating without using the first laminate and the second laminate As shown in Comparative Example 2, the protective sheets on both sides of the silicone rubber sheet with the double-sided protective sheet were peeled on the glass substrate. After that, it was placed and laminated, and then a four-line single crystal silicon solar cell element matrix was placed and laminated. Next, as shown in Comparative Example 1, after peeling the protective sheets on both sides of the silicone rubber sheet with the double-sided protective sheet, the silicone rubber sheet was placed and laminated on the solar cell element matrix, and the backsheet was further laminated. After placing and laminating, vacuum lamination was performed at 30 ° C.
This was placed in a heating furnace heated to 130 ° C. for 30 minutes to cure the silicone rubber sheet, thereby producing a solar cell module F.

[Comparative Example 5]: Method of laminating without using the first laminated body and the second laminated body, and vulcanizing with a vacuum laminator as it is In Comparative Example 4, instead of performing the vacuum laminating process at 30 ° C., the plate temperature Was set in a vacuum laminator heated to 130 ° C., and after reducing the pressure for 5 minutes, confirm that the degree of vacuum in the lower chamber was 100 Pa or less, and pressing the upper chamber to atmospheric pressure for 30 minutes. A solar cell module G was manufactured in the same manner as in Comparative Example 4 except that vulcanization was performed.

[Reference Example 1]: Method of laminating using the first laminate and the second laminate, and vulcanizing with a vacuum laminator as it is In Example 1, a step of sealing a matrix with a vacuum laminator at 30 ° C. and a heating furnace Instead of the step of curing the silicone rubber sheet according to, after setting the plate temperature in a vacuum laminator heated to 130 ° C, after confirming that the decompression degree of the lower chamber became 100 Pa or less after reducing the pressure for 5 minutes A solar cell module H was manufactured in the same manner as in Example 1 except that the upper chamber was set to atmospheric pressure and pressed for 30 minutes until vulcanization.
Table 1 summarizes the sealing steps of Examples 1-2, Comparative Examples 1-5, and Reference Example 1.

  Next, in Examples 1-2, Comparative Examples 1-5, and Reference Example 1, the sealing state of each solar cell module with a cured silicone rubber was observed.

  Table 2 shows the evaluation observation results. In the sealing evaluation, the transparent panel (light-receiving surface glass) and the back sheet side of the solar cell module are visually observed from the outside, and the unsealed portion caused by voids (gap) in the entire area of each surface is observed. A state where the area ratio was less than 1% was judged as “◯”, a state where it was 1% or more and less than 5% was judged as “Δ”, and a state where it was 5% or more was judged as “x”.

DESCRIPTION OF SYMBOLS 1 Transparent panel 2 Panel or back sheet 3a, 3b Silicone rubber sheet 4a, 4b Protection sheet 5 Solar cell element matrix 6 Solar cell element 7 Interconnector 10 Vacuum laminator 11 Diaphragm sheet 12 Plate 20 1st laminated body 30 2nd laminated body 40 Composite laminate

Claims (4)

A solar cell module for manufacturing a solar cell module by resin-sealing a solar cell element matrix formed by connecting a plurality of solar cell elements interposed between transparent panels or between a transparent panel and a back sheet In the manufacturing method,
(1) A step of preparing a first laminate in which an unvulcanized silicone rubber sheet made of a millable type silicone rubber composition is bonded to one surface of a transparent panel at a temperature between 10 ° C. and 50 ° C. under reduced pressure;
(2) A step of preparing a second laminate in which an unvulcanized silicone rubber sheet made of a millable type silicone rubber composition is attached to one surface of a panel or a back sheet at 10 ° C. to 50 ° C. under reduced pressure; ,
(3) The first laminated body and the second laminated body are arranged with their silicone rubber sheet surfaces facing each other, and a solar cell matrix is arranged therebetween, and the pressure is reduced between 10 ° C. and 50 ° C. in that state. And pressing the first laminate and the second laminate to seal the solar cell matrix;
(4) A step of heating the sealed laminated body between 70 ° C. and 150 ° C. for 20 to 50 minutes to cure the silicone rubber sheet;
The manufacturing method of the solar cell module characterized by having.   The step (2) is a step of preparing a backsheet-silicone rubber composite in which an unvulcanized silicone rubber made of a millable type silicone rubber composition is topped on one surface of the backsheet by a calendar method. The method for manufacturing a solar cell module according to claim 1, wherein: The silicone rubber composition is
(A) The following average composition formula (I)
R ¹ _a SiO _{(4-a) / 2} (I)
(In the formula, R ¹ represents the same or different unsubstituted or substituted monovalent hydrocarbon group, and a is a positive number of 1.95 to 2.05.)
100 parts by mass of an organopolysiloxane having at least two alkenyl groups in one molecule represented by
(B) 10 to 150 parts by mass of reinforcing silica having a specific surface area of 50 m ² / g or more,
(C) Hardener (A) The manufacturing method of the solar cell module of Claim 1 or 2 containing the effective amount which hardens | cures a component.   The method for producing a solar cell module according to claim 3, wherein the component (C) is a combination of an organohydrogenpolysiloxane and a hydrosilylation reaction catalyst, or an organic peroxide.

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