JP2015115442A - Method for manufacturing solar battery module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a solar battery module, by which a conventional apparatus for manufacturing a solar battery module can be used in a process of encapsulating a solar battery element in a silicone rubber or gel as an encapsulation material without bringing air bubbles therein.SOLUTION: The method for manufacturing a solar battery module includes steps of: (1) preparing a surface panel by forming a silicone rubber or gel layer on a transparent panel where sun rays are to enter; (2) preparing a back panel by forming a silicone rubber or gel layer on a panel on an opposite side to the surface where sun rays enter; (3) forming an uncured silicone rubber adhesive layer in a frame-like pattern in an outer periphery of the surface panel or the back panel; and (4) interposing solar battery cell strings between the silicone rubber or gel layer of the surface panel and the silicone rubber or gel layer of the back panel, pinching the surface panel and the back panel to bury and encapsulate the solar battery cell strings in the silicone rubber or gel layers, as well as to cure the silicone rubber adhesive layer to bond the surface panel and the back panel.

Description

  The present invention relates to a method for manufacturing a solar cell module.

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 higher efficiency, silicone rubber is an internal component based on light transmittance characteristics in the vicinity of a wavelength of 300 to 400 nm as compared with ethylene-vinyl acetate copolymer (hereinafter abbreviated as EVA), which is the mainstream of sealing materials. The superiority of quantum efficiency has been reported (for example, see Non-Patent Document 1), and a comparison experiment of output power when EVA and silicone rubber are actually used as a sealing material has also been reported (for example, Non-Patent Document 1). 2).
Originally, the use of silicone rubber as a sealing material has already been achieved in the production of solar cells for space use in the early 1970s. When manufacturing it for ground use, there was a problem of cost of silicone rubber and workability at the time of sealing, so that it was replaced with EVA that was low-cost and could be supplied by film at that time.

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

  For example, Patent Document 3 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. Moreover, in order to improve the “brittleness”, fillers such as fillers can be mixed to improve moldability. However, there is a drawback that high transparency cannot be maintained.

  In Patent Document 2, a solar cell connected to an uncured silicone rubber material coated on a substrate or in a silicone rubber material is placed by a multi-axis robot, and then the silicone rubber material is cured to thereby eliminate bubbles. It has been proposed to enclose without taking up. Further, Patent Document 3 proposes that a cell press having a movable plate is used and sealing is performed without taking in bubbles by arranging solar cells under vacuum. However, in any of the methods, the treatment of the end face of the solar cell module is not mentioned, which is greatly different from the conventional solar cell sealing method, and may not be able to cope with the current mass production apparatus. On the other hand, in Patent Document 4, a sealing agent, a solar cell element, and liquid silicone rubber are disposed on a glass substrate, and finally a back protective substrate is stacked to form a temporary laminate, which is sealed by pressure contact under vacuum at room temperature. Although a method has been proposed, it may be difficult to expand the solar cell module to a practical size by this method.

  Moreover, in patent document 5, after arrange | positioning the sealing S ring composition in the thickness direction of glass peripheral part, and also arrange | positioning resin, such as EVA, on the inner side of the said sealing composition, the multilayer glass by carrying out the thermocompression bonding under pressure reduction, and A method for sealing a solar cell panel is described. However, in this method, EVA melted at the time of thermocompression bonding protrudes from the peripheral portion of the glass, which may hinder the adhesion performance of the sealing composition to the glass.

Special table 2009-515365 Special table 2007-527109 gazette Special table 2011-514680 gazette International Publication No. 2009/09106 JP 2011-231309 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

  An object of the present invention is to provide a solar cell by silicone rubber or gel sealing that can be used by a conventional solar cell module manufacturing apparatus without taking in bubbles when sealing a solar cell element with silicone rubber or gel as a sealing material. It is providing the manufacturing method of a battery module.

  As a result of intensive studies to achieve the above object, the present inventors have found that at least one of the front side panel and the back side panel or sheet on which the silicone rubber or gel layer is laminated and the outer peripheral portion of the silicone rubber or gel layer forming surface. A hydrosilylation reaction-curable silicone rubber adhesive layer is formed in a frame shape, solar cell strings are sandwiched between the two silicone rubbers or gel layers, and bubbles are taken in by pressing at a temperature of 60 to 200 ° C. under vacuum. In addition, the solar cell strings can be sealed with both silicone rubbers or gel layers, and the silicone rubber adhesive layer can be cured to join the front side panel and the back side panel or sheet. It has been found that the solar cell module manufacturing apparatus can be used, and the present invention has been made.

Therefore, this invention provides the manufacturing method of the following solar cell module.
[1]
(1) A step of preparing a front side panel in which a liquid silicone rubber or gel composition is applied to one side of a transparent panel on which sunlight is incident and cured to form a silicone rubber or gel layer.
(2) A step of preparing a back side panel or sheet in which a liquid silicone rubber or gel composition is applied to one side of a panel or sheet opposite to the incidence of sunlight and cured to form a silicone rubber or gel layer;
(3) A step of forming an uncured silicone rubber adhesive layer that is cured by a hydrosilylation reaction in the form of a frame on the outer peripheral portion of the surface on the silicone rubber or gel layer forming side of at least one of the front panel and the back panel or sheet;
(4) A solar battery cell string in which a plurality of solar battery elements made of a semiconductor substrate are connected between the silicone rubber or gel layer of the front panel and the silicone rubber or gel layer of the back panel or sheet is sandwiched between 60 and 200. The front panel and the back panel or sheet are sandwiched between the front panel and the rear panel under vacuum at a temperature of C to embed and seal the solar cell strings in both silicone rubbers or gel layers, and to cure the silicone rubber adhesive layer. The manufacturing method of the solar cell module characterized by including the process of joining a front side panel, a back side panel, or a sheet | seat.
[2]
[1] The production method according to [1], wherein the hardness of the silicone rubber or gel layer is 50 or less by a type A durometer defined by JIS K6253 and a penetration by a ¼ cone defined by JIS K2220 is 200 or less. .
[3]
Liquid silicone rubber or gel composition
(A) The following average composition formula (1)
R _a R ¹ _b SiO _{(4-ab) / 2} (1)
(In the formula, R is independently an alkenyl group, R ¹ is independently an unsubstituted or halogen atom-substituted monovalent hydrocarbon group not containing an aliphatic unsaturated bond, and a is from 0.0001 to 0.2. And b is a positive number of 1.7 to 2.2, where a + b is 1.9 to 2.4.)
An organopolysiloxane having at least one alkenyl group bonded to a silicon atom in one molecule represented by:
(B) Organohydrogenpolysiloxane having at least two hydrogen atoms bonded to silicon atoms in one molecule: The number of silicon atom-bonded hydrogen atoms in this component is 0 per silicon atom-bonded alkenyl group in component (A). 3. An amount of 3 to 10 and (C) a platinum-based catalyst: an addition-curable liquid silicone rubber or gel composition using a hydrosilylation reaction containing an effective amount, according to [1] or [2] Method.
[4]
Any one of [1] to [3] in which the outer peripheral portion of the front side panel and the outer peripheral portion of the back side panel or sheet are silicone rubber or gel layer non-formed portions, and the silicone rubber adhesive layer is disposed on the non-formed portions. The manufacturing method as described in.
[5]
The production method according to any one of [1] to [4], wherein the plasticity of the silicone rubber adhesive layer in an uncured state at 23 ° C. is within a range of 100 to 600 as measured by a Williams plasticity meter.
[6]
Silicone rubber adhesive
(D) The following average composition formula (3)
R ¹¹ _X SiO _{(4-X) / 2} (3)
(In the formula, R ¹¹ is an unsubstituted or substituted monovalent hydrocarbon group, and 0.001 to 1.0 mol% in R ¹¹ is an alkenyl group. X is a positive value of 1.95 to 2.05. Number.)
100 parts by mass of an organopolysiloxane containing at least two alkenyl groups in one molecule represented by
(E) Reinforcing silica: 5-200 parts by mass,
(F) platinum-based catalyst: effective amount,
(G) Organohydrogenpolysiloxane containing at least two hydrogen atoms bonded to silicon atoms in one molecule: The ratio of hydrogen atoms bonded to silicon atoms to one alkenyl group in component (D) is 0 The manufacturing method in any one of [1]-[5] which uses the quantity used as 3-10 pieces as an essential component.
[7]
Silicone rubber adhesive is formed into a string shape in advance, and this is arranged in a frame shape along the outer periphery of the surface panel or the back panel or the outer periphery of the sheet, or is formed into a rectangular frame shape in advance. The manufacturing method according to any one of [1] to [6], wherein a silicone rubber adhesive layer is formed by disposing the outer peripheral portion or the back side panel or the outer peripheral portion of the sheet.

The method for manufacturing a solar cell module of the present invention includes a transparent panel that allows sunlight to enter when a solar cell element is sealed with silicone rubber or gel as a sealing material, and a panel that is a substrate opposite to sunlight incidence. A liquid silicone rubber or gel composition is applied on a sheet, and a cured silicone rubber or gel is used, and the solar cell element is placed between panels or between panels by pressing under vacuum at 60 to 200 ° C. Since it is manufactured by sandwiching between sheets, excessive pressure on the solar cell element applied at the time of pressing can be achieved by placing a silicone rubber adhesive in the shape of a frame on the outer peripheral part of one side of the panel or sheet at the same time without taking in bubbles. By using a silicone rubber adhesive that suppresses, prevents the destruction of solar cell elements and has excellent durability, Compared to organic sealing material such as butyl rubber which is used as a sealing material of the module, there is no influence of the liquid silicone rubber or gel cured product is a sealing material. Furthermore, since the vacuum laminator, which is a conventional solar cell module manufacturing apparatus using an EVA film, can be used in the process of manufacturing by pressing under vacuum, a solar cell module can be manufactured without preparing a new apparatus for laminating. can do.
Furthermore, even when the thickness of the solar cell element becomes 100 μm or less in the future, when laminating the solar cell element, a liquid silicone rubber or gel composition cured product having low modulus, low hardness and light resistance is used. By sealing, high efficiency and long-term reliability are maintained.

Hereinafter, the suitable aspect of the manufacturing method of the solar cell module of this invention is demonstrated.
In the method for producing a solar cell module of the present invention, a liquid silicone rubber or gel composition is applied to a transparent panel on which sunlight is incident, and the liquid silicone rubber or panel or sheet on the opposite side to the sunlight incidence is cured or A panel or sheet coated with a gel composition and cured is used.

  Here, the transparent panel on which the sunlight is incident needs a member having long-term reliability in outdoor use including transparency, weather resistance, and impact resistance. For example, white plate reinforced glass, acrylic resin, fluorine Resin or polycarbonate resin is available, but generally white plate tempered glass having a thickness of about 3 to 5 mm is preferred.

  Moreover, in the panel or sheet | seat on the opposite side to the said sunlight incidence, heat dissipation and the insulation of the temperature of a solar cell element are calculated | required efficiently, and a glass material, a synthetic resin material, and a composite material are mentioned as a material. Examples of the glass material include blue plate glass, white plate glass, or tempered glass, and examples of the synthetic resin material include panels such as acrylic resin, polycarbonate (PC) resin, polyethylene terephthalate (PET) resin, and epoxy resin. . Examples of the composite material include a panel made of synthetic resin or the like in which a material having high thermal conductivity such as silica, titanium oxide, alumina, and aluminum nitride is blended. Examples of the sheet include a so-called back sheet such as a fluororesin and a polyethylene terephthalate (PET) resin.

  In addition, in the panel or sheet on the side opposite to sunlight incidence, by using a transparent member together with the panel on which sunlight is incident, direct sunlight and a part of the scattered light are partly opposite to sunlight incidence. For example, when it is installed on a grassland or the like, a part of sunlight is irradiated to a part opposite to the incident surface of the solar cell module, that is, a part that is originally shaded. It can be used for grazing livestock.

In the present invention, a liquid silicone rubber or gel composition is applied to the transparent panel on the sunlight incident side and the panel or sheet on the opposite side to the sunlight incident, respectively, and cured to form silicone on one side of the panel or sheet. A rubber or gel layer is formed. In this case, as the liquid silicone rubber or gel composition,
(A) The following average composition formula (1)
R _a R ¹ _b SiO _{(4-ab) / 2} (1)
(In the formula, R is independently an alkenyl group, R ¹ is independently an unsubstituted or halogen atom-substituted monovalent hydrocarbon group not containing an aliphatic unsaturated bond, and a is from 0.0001 to 0.2. And b is a positive number of 1.7 to 2.2, where a + b is 1.9 to 2.4.)
An organopolysiloxane having at least one alkenyl group bonded to a silicon atom in one molecule represented by:
(B) Organohydrogenpolysiloxane having at least two hydrogen atoms bonded to silicon atoms in one molecule: The number of silicon atom-bonded hydrogen atoms in this component is 0 per silicon atom-bonded alkenyl group in component (A). An amount of 3 to 10 and (C) platinum-based catalyst: An addition-curable liquid silicone rubber or gel composition using a hydrosilylation reaction containing an effective amount is preferred.

  Here, (A) component is the main ingredient (base polymer) of a silicone rubber composition. The component (A) has at least one alkenyl group (referred to as “silicon atom-bonded alkenyl group” in this specification) bonded to a silicon atom in one molecule represented by the above average composition formula (1). Organopolysiloxane.

In the above formula (1), R is independently an alkenyl group usually having 2 to 6, preferably 2 to 4, more preferably 2 to 3 carbon atoms. Specific examples thereof include a vinyl group, an allyl group, a propenyl group, an isopropenyl group, a butenyl group, and an isobutenyl group, and a vinyl group is preferable. In the present invention, an acryl group and a methacryl group are not included in the alkenyl group. R ¹ independently represents an unsubstituted or halogen atom-substituted monovalent hydrocarbon group that does not contain an aliphatic unsaturated bond, and the number of carbon atoms is usually 1 to 10, preferably 1 to 6. Specific examples thereof include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, hexyl group, cyclohexyl group, octyl group and decyl group; phenyl group An aryl group such as a tolyl group; an aralkyl group such as a benzyl group or a phenylethyl group; a chloromethyl group in which some or all of the hydrogen atoms of these groups are substituted with a halogen atom such as chlorine, bromine or fluorine; 3,3-trifluoropropyl group and the like can be mentioned. Among them, a methyl group, a phenyl group, or a 3,3,3-trifluoropropyl group is preferable because synthesis is easy. R ¹ , and therefore the organopolysiloxane of formula (1), does not contain epoxy groups or alkoxy groups.

  Moreover, a needs to be a positive number of 0.0001 to 0.2, and is preferably a positive number of 0.0005 to 0.1. b needs to be a positive number of 1.7 to 2.2, and is preferably a positive number of 1.9 to 2.02. However, a + b needs to satisfy the range of 1.9 to 2.4, and preferably 1.95 to 2.05.

  This component needs to have at least one silicon atom-bonded alkenyl group in one molecule, preferably 2 to 50, more preferably 2 to 10. What is necessary is just to select the value of said a and b so that the conditions of this silicon atom bond alkenyl group may be satisfy | filled.

（式中、Ｒ²は独立に脂肪族不飽和結合を含まない非置換又はハロゲン原子置換の１価炭化水素基であり、Ｒ³は独立に脂肪族不飽和結合を含まない非置換又はハロゲン原子置換の１価炭化水素基、又はアルケニル基であり、但し少なくとも１個のＲ³はアルケニル基であり、分子鎖両末端のＲ³のいずれかがアルケニル基である場合には、ｋは４０〜１，２００の整数であり、ｍは０〜５０の整数であり、ｎは０〜５０の整数であり、分子鎖両末端のＲ³のいずれもがアルケニル基でない場合には、ｋは４０〜１，２００の整数であり、ｍは１〜５０の整数であり、ｎは０〜５０の整数であり、但しｍ＋ｎは１以上である。）
で表されるオルガノポリシロキサン、即ち主鎖が基本的にジオルガノシロキサン単位の繰り返しからなり、分子鎖両末端がトリオルガノシロキシ基で封鎖された直鎖状のジオルガノポリシロキサンであることが好ましい。 The molecular structure of the organopolysiloxane of this component is not particularly limited, and even if it is linear, for example, RSiO _3/2 unit, R ¹ SiO _3/2 unit, SiO ₂ unit, etc. (R and R ¹ are as described above) The same general formula (1a) may be used.

(In the formula, R ² independently represents an unsubstituted or halogen atom-substituted monovalent hydrocarbon group that does not contain an aliphatic unsaturated bond, and R ³ independently represents an unsubstituted or halogen atom that does not contain an aliphatic unsaturated bond. A substituted monovalent hydrocarbon group or an alkenyl group, provided that at least one R ³ is an alkenyl group, and when either R ³ at both ends of the molecular chain is an alkenyl group, k is 40 to 40 An integer of 1,200, m is an integer of 0 to 50, n is an integer of 0 to 50, and when neither R ³ at both ends of the molecular chain is an alkenyl group, k is 40 to 40 (It is an integer of 1,200, m is an integer of 1 to 50, n is an integer of 0 to 50, provided that m + n is 1 or more.)
Is preferably a linear diorganopolysiloxane in which the main chain basically consists of repeating diorganosiloxane units and both ends of the molecular chain are blocked with triorganosiloxy groups. .

In the above formula (1a), the unsubstituted or halogen atom-substituted monovalent hydrocarbon group not containing an aliphatic unsaturated bond other than the alkenyl group represented by R ² is usually 1 to 10 carbon atoms, preferably 1 ~ 6. Specific examples thereof include those exemplified for R ¹ . Among them, a methyl group, a phenyl group, or a 3,3,3-trifluoropropyl group is preferable because synthesis is easy.

Further, the unsubstituted or halogen atom-substituted monovalent hydrocarbon group independently containing an aliphatic unsaturated bond represented by R ³ is usually one having 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms. Specific examples thereof include those exemplified for R ¹ . Among them, a methyl group, a phenyl group, or a 3,3,3-trifluoropropyl group is preferable because synthesis is easy. The alkenyl group represented by R ³ usually has 2 to 6 carbon atoms, preferably 2 to 4 carbon atoms, more preferably 2 to 3 carbon atoms. Specific examples thereof include a vinyl group, an allyl group, a propenyl group, an isopropenyl group, a butenyl group, and an isobutenyl group, and a vinyl group is preferable.

In the above formula (1a), when either R ³ at both ends of the molecular chain is an alkenyl group, k is an integer of 100 to 1,000, m is an integer of 0 to 40, and n is In the case where R ³ at both ends of the molecular chain is not an alkenyl group, k is an integer of 100 to 1,000, m is an integer of 2 to 40, and n is 0. Preferably there is.

  Examples of the organopolysiloxane represented by the above formula (1a) include dimethylpolysiloxane having both ends dimethylvinylsiloxy group-blocked dimethylpolysiloxane, dimethylvinylsiloxy group-blocked dimethylsiloxane / methylvinylsiloxane copolymer, and both ends dimethylvinylsiloxy. Blocked dimethylsiloxane / diphenylsiloxane copolymer, both ends dimethylvinylsiloxy group-blocked dimethylsiloxane / methylvinylsiloxane / diphenylsiloxane copolymer, both ends dimethylvinylsiloxy-blocked methyltrifluoropropylpolysiloxane, both ends dimethylvinylsiloxy Capped dimethylsiloxane / methyltrifluoropropylsiloxane copolymer, dimethylvinylsiloxy group-capped dimethylsiloxane / methyltrifluoropropylsiloxane at both ends Methyl vinyl siloxane copolymer, Trimethylsiloxy group-capped dimethylsiloxane / vinylmethylsiloxane copolymer, Trimethylsiloxy group-capped dimethylsiloxane / vinylmethylsiloxane / diphenylsiloxane copolymer, Trimethylsiloxy group-capped vinylmethyl Siloxane / methyltrifluoropropylsiloxane copolymer, terminal trimethylsiloxy group / dimethylvinylsiloxy group-capped dimethylpolysiloxane, terminal trimethylsiloxy group / dimethylvinylsiloxy group-capped dimethylsiloxane / methylvinylsiloxane copolymer, terminal trimethylsiloxy group / Dimethylvinylsiloxy group-capped dimethylsiloxane / diphenylsiloxane copolymer, terminal trimethylsiloxy group / dimethylvinylsiloxy group-capped dimethylene Polysiloxane / diphenylsiloxane / methylvinylsiloxane copolymer, terminal trimethylsiloxy group / dimethylvinylsiloxy group-capped methyltrifluoropropylpolysiloxane, terminal trimethylsiloxy group / dimethylvinylsiloxy group-capped dimethylsiloxane / methyltrifluoropropylsiloxane copolymer Copolymer, terminal trimethylsiloxy group / dimethylvinylsiloxy group-capped dimethylsiloxane / methyltrifluoropropylsiloxane / methylvinylsiloxane copolymer, both end methyldivinylsiloxy group-capped dimethylpolysiloxane, both end methyldivinylsiloxy group-capped dimethylsiloxane / methyl Vinylsiloxane copolymer, both ends methyldivinylsiloxy group-blocked dimethylsiloxane / diphenylsiloxane copolymer, both ends methyl Rudivinylsiloxy group-blocked dimethylsiloxane / methylvinylsiloxane / diphenylsiloxane copolymer, both ends methyldivinylsiloxy group-blocked methyltrifluoropropylpolysiloxane, both ends methyldivinylsiloxy group-blocked dimethylsiloxane / methyltrifluoropropylsiloxane copolymer , Both ends methyldivinylsiloxy group-blocked dimethylsiloxane / methyltrifluoropropylsiloxane / methylvinylsiloxane copolymer, both ends trivinylsiloxy group-blocked dimethylpolysiloxane, both ends trivinylsiloxy-blocked dimethylsiloxane / methylvinylsiloxane copolymer Combined, trivinylsiloxy group-capped dimethylsiloxane / diphenylsiloxane copolymer, both ends trivinylsiloxy group-capped dimethylsiloxane / medium Ruvinylsiloxane / diphenylsiloxane copolymer, trivinylsiloxy group-blocked methyltrifluoropropyl polysiloxane at both ends, trivinylsiloxy group-blocked dimethylsiloxane / methyltrifluoropropylsiloxane copolymer, trivinylsiloxy group-blocked at both ends Examples thereof include dimethylsiloxane / methyltrifluoropropylsiloxane / methylvinylsiloxane copolymer.

  The viscosity at 23 ° C. of the organopolysiloxane of this component measured by a rotational viscometer is not particularly limited, but it is 50 to 100,000 mPa from the point that the handling workability of the composition, the strength and fluidity of the resulting cured product become good. · It is preferably s, more preferably 100 to 10,000 mPa · s.

  Next, the component (B) reacts with the component (A) and acts as a crosslinking agent. The component (B) has at least two hydrogen atoms bonded to silicon atoms in one molecule (that is, SiH groups (hydrosilyl groups), referred to herein as “silicon atom-bonded hydrogen atoms”). Organohydrogenpolysiloxane.

  The silicon-bonded hydrogen atom contained in the organohydrogenpolysiloxane of this component may be located at either the molecular chain end or in the middle of the molecular chain, or may be located at both of them. The molecular structure is not particularly limited, and may be any of linear, cyclic, branched and three-dimensional network structures (resin-like).

  The number of silicon atoms in one molecule of the organohydrogenpolysiloxane of this component (that is, the degree of polymerization) is usually 4 to 1,000, but the handling workability of the composition and the properties of the resulting cured product ( The number is preferably 10 to 1,000, more preferably 10 to 400, from the viewpoint that the low elastic modulus and low stress are good.

  The viscosity at 23 ° C. by a rotational viscometer is usually 10 to 100,000 mPa · s, preferably 20 to 10,000 mPa · s, more preferably 50 to 5,000 mPa · s, and room temperature (23 ° C.). A liquid one is preferably used.

The organohydrogenpolysiloxane of this component has the following average composition formula (2)
R ⁴ _c H _d SiO _{(4-cd) / 2} (2)
(In the formula, R ⁴ independently represents an unsubstituted or halogen atom-substituted monovalent hydrocarbon group not containing an aliphatic unsaturated bond, c is a positive number of 0.7 to 2.2, and d is 0. .001-0.5, where c + d is 0.8-2.5.)
What is represented by these is used suitably.

In said formula (2), R < ⁴ > is the monovalent | monohydric hydrocarbon group of the unsubstituted or halogen atom substitution which does not contain an aliphatic unsaturated bond independently, The carbon atom number is 1-10 normally, Preferably it is 1 6. Specific examples thereof include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group, cyclohexyl group, octyl group, nonyl group, decyl group. An alkyl group such as phenyl group, tolyl group, xylyl group, naphthyl group, etc .; aralkyl group such as benzyl group, phenylethyl group, phenylpropyl group, etc .; , 3,3,3-trifluoropropyl groups substituted with halogen atoms such as bromine and fluorine. Among these, an alkyl group, an aryl group, and a 3,3,3-trifluoropropyl group are preferable, and a methyl group, a phenyl group, and a 3,3,3-trifluoropropyl group are more preferable. R ⁴ , and therefore the organohydrogenpolysiloxane of the formula (2) does not contain an epoxy group or an alkoxy group.

  Further, c is preferably a positive number of 1.0 to 2.1, d is preferably a positive number of 0.001 to 0.1, and is a positive number of 0.005 to 0.1. More preferably, it is more preferably a positive number of 0.005 to 0.05, particularly preferably a positive number of 0.005 to 0.03, and c + d is 1.0 to 2.5. It is preferable to satisfy | fill the range of 1.5, and it is especially preferable to satisfy | fill the range of 1.5-2.2.

Examples of the organohydrogenpolysiloxane represented by the above formula (2) include a methylhydrogensiloxane / dimethylsiloxane cyclic copolymer, a trimethylsiloxy group-blocked methylhydrogenpolysiloxane having both ends, and a trimethylsiloxy group-blocked dimethyl having both ends. Siloxane / methylhydrogensiloxane copolymer, both ends dimethylhydrogensiloxy-blocked dimethylpolysiloxane, both ends dimethylhydrogensiloxy-blocked dimethylsiloxane / methylhydrogensiloxane copolymer, both ends trimethylsiloxy-blocked methylhydrogen Siloxane / diphenylsiloxane copolymer, both ends trimethylsiloxy group-blocked methylhydrogensiloxane / diphenylsiloxane / dimethylsiloxane copolymer Both ends endcapped with dimethyl hydrogen siloxy group methylhydrogensiloxane-dimethylsiloxane-diphenylsiloxane copolymer, and (CH _{3) 2} HSiO _1/2 units and (CH _{3) 3} SiO _1/2 units and SiO _4/2 units A copolymer comprising (CH ₃ ) ₂ HSiO _1/2 units and SiO _4/2 units, (CH ₃ ) ₂ HSiO _1/2 units and (C ₆ H ₅ ) SiO _{3/2 Examples} thereof include a copolymer comprising units and SiO _4/2 units.

  The blending amount of this component needs to be an amount that makes 0.3 to 10 silicon atom-bonded hydrogen atoms in this component per one silicon atom-bonded alkenyl group in component (A), preferably Is an amount of 0.5 to 5, more preferably 0.6 to 2. When the number of silicon atom-bonded hydrogen atoms is less than 0.3, the crosslinking density becomes too low, and the resulting composition may not be cured, or even when cured, the heat resistance of the cured product may be reduced. When it is more than the number, problems of foaming due to dehydrogenation reaction may occur, and the heat resistance of the obtained cured product may be lowered.

  Furthermore, the component (C) is used as a catalyst for promoting the addition reaction between the silicon atom-bonded alkenyl group in the component (A) and the silicon atom-bonded hydrogen atom in the component (B). is there. The component (C) is a platinum-based catalyst (platinum or a platinum-based compound), and a known one can be used. Specific examples thereof include alcohol-modified products such as platinum black, chloroplatinic acid, and chloroplatinic acid; complexes of chloroplatinic acid and olefins, aldehydes, vinyl siloxanes, acetylene alcohols, and the like.

  The compounding amount of this component may be an effective amount, and can be appropriately increased or decreased depending on the desired curing rate. Usually, it is the mass of the platinum atom with respect to the total amount of the components (A) and (B), and is usually 0.00. It is in the range of 1 to 1,000 ppm, preferably 1 to 300 ppm. If the amount is too large, the heat resistance of the resulting cured product may decrease. On the other hand, when there are too few compounding quantities, a composition may not fully harden | cure.

  In addition to the components (A) to (C), various components can be blended in the liquid silicone rubber or gel composition of the present invention as necessary.

  From the viewpoint of imparting self-adhesiveness, a silicon compound containing a functional group that imparts adhesiveness can be blended as an adhesion-imparting agent. Specific examples of the functional group include vinyl groups bonded to silicon atoms, alkenyl groups such as allyl groups, and epoxy groups bonded to silicon atoms via carbon atoms (for example, γ-glycidoxypropyl group, β- (3,4-epoxycyclohexyl) ethyl group), (meth) acryloxy group (for example, γ-acryloxypropyl group, γ-methacryloxypropyl group, etc.), alkoxysilyl group (for example, ester structure, urethane structure, ether) An alkoxysilyl group such as a trimethoxysilyl group, a triethoxysilyl group, or a methyldimethoxysilyl group bonded to a silicon atom via an alkylene group that may contain one or two structures), an organosilane having a SiH group, and Siloxane oligomers and tria having 3 to 50 silicon atoms, especially 5 to 20 linear or cyclic structures Etc. (alkoxy) silyl-modified products and their siloxane derivative Le isocyanurate. In the present invention, those containing two or more of these functional groups in one molecule are particularly preferable. Particularly, the alkenyl group and the SiH group are used in combination with at least one of an epoxy group, a (meth) acryloxy group and an alkoxysilyl group, respectively. To do. Specific examples of the silicon compound containing such a functional group include the following.

  In addition, the compounding quantity of the said adhesion imparting agent is 0-10 mass parts with respect to 100 mass parts of (A) component, More preferably, it is 0.5-5 mass parts, More preferably, it is 1-5 mass parts.

  Furthermore, from the viewpoint of assisting self-adhesion, the adhesion can be improved by blending a condensation catalyst such as an organic titanium compound and an organic zirconium compound as an adhesion promoter. Specifically, as an organic titanium compound, organic titanates such as tetraisopropyl titanate, tetrabutyl titanate, tetraoctyl titanate; diisopropoxybis (acetylacetonate) titanium, diisopropoxybis (ethyl acetoacetate) Examples include titanium chelate compounds such as titanium. Examples of the organic zirconium compound include tetrapropoxyzirconium, tetrabutoxyzirconium, zirconium tetraacetylacetonate, zirconium tributoxyacetylacetonate, and zirconium tributoxy systemate.

  In addition, the compounding quantity of the said adhesion promoter is 0-5 mass parts with respect to 100 mass parts of (A) component, More preferably, it is 0.1-5 mass parts, More preferably, it is 0.1-2 mass parts. .

  On the other hand, the liquid silicone rubber or gel composition to be applied / cured on the back panel or sheet opposite to the sunlight incident, for the purpose of imparting rubber strength, rubber hardness, light reflectance, and heat dissipation, if necessary, Reinforcing inorganic fillers such as fumed silica and titanium dioxide, and non-reinforcing inorganic fillers such as crystalline silica, calcium silicate, titanium dioxide, ferric oxide, carbon black, and alumina can also be blended.

  Further, in order to control the reaction of the platinum-based catalyst, a reaction control agent represented by vinylmethylcyclopolysiloxanes and acetylene alcohols may be added.

  The liquid silicone rubber or gel composition can be prepared by mixing the above components (A) to (C) (including optional components when optional components are blended) according to a conventional method. At that time, the components to be mixed may be divided into two or more parts as needed, and mixed, for example, (A) part of component and (C) component part, It is also possible to divide and mix the remaining part of component A) and the part composed of component (B).

  The viscosity at 23 ° C. of the liquid silicone rubber or gel composition is preferably 1,000 Pa · s or less, particularly preferably 100 Pa · s or less. The viscosity measurement in this case is a value measured using a rotational viscometer.

  Application methods for applying / curing the liquid silicone rubber or gel composition to the front panel and back panel or sheet include spray coating, curtain coating, knife coating, and screen coating. Any method may be used. Further, at the time of application, it is desirable to form an uncoated part of the liquid silicone rubber or gel composition in a frame shape along the outer periphery of the panel or sheet to be coated, but it is not essential. In this uncoated portion, a silicone rubber adhesive necessary for the next step is arranged. When the silicone rubber adhesive is disposed, if the liquid silicone rubber cured product remains in the disposed portion, the adhesion between the silicone rubber adhesive and the panel may be reduced. In order to form an uncoated part, it is good to mask in frame shape with a tape beforehand, before apply | coating uncured liquid silicone rubber or a gel composition. However, by using a silicone rubber adhesive that adheres to a cured liquid silicone rubber or gel composition, the silicone rubber adhesive is placed directly on the panel or sheet coated / cured with the liquid silicone rubber or gel composition. However, it is also possible to have good adhesiveness, and it is possible to manufacture a silicone-sealed solar cell module having the intended durability.

  After applying the liquid silicone rubber or gel composition to the panel or sheet, the liquid silicone rubber or the gel composition cured from the liquid silicone rubber or gel composition by curing at 60 to 150 ° C. for 5 to 30 minutes by a conventional method. A gel layer is obtained.

  In this case, it is preferable to adjust the film thickness of the silicone rubber or gel layer to 200 to 1,000 μm, and more preferably in the range of 300 to 800 μm. When the film thickness is less than 200 μm, the solar cell element is cracked in the process of manufacturing the solar cell element made of a semiconductor substrate between the panels, and the solar cell element particularly in an outdoor environment where the temperature rises and falls. A difference in coefficient of linear expansion and modulus with the wiring connection portion on the surface cannot be absorbed, and the solar cell element may be embrittled. On the other hand, if the film thickness is thicker than 1,000 μm, it takes time to cure, and the amount of liquid silicone rubber or gel composition used increases, which may increase the cost.

  Furthermore, the hardness after curing of the liquid silicone rubber or gel composition is preferably lower in order to prevent the solar cell element from cracking in the process of manufacturing the solar cell element sandwiched between the panels. Therefore, it is desirable that the hardness is 50 or less, preferably 30 or less, using a type A durometer defined by JIS K6253. If the hardness is greater than 50, the characteristics of silicone rubber such as low modulus and low hardness cannot be exhibited, and the solar cell element is cracked in the process of manufacturing the solar cell element made of a semiconductor substrate between the panels, especially the temperature. In an outdoor environment where the lifting and lowering occurs, it becomes impossible to absorb the difference in coefficient of linear expansion and modulus with the wiring connection portion on the surface of the solar cell element, which may cause embrittlement of the solar cell element. Furthermore, a gel-like cured silicone rubber is particularly preferable, and specifically, a silicone having a penetration after application / curing of 30 to 200 in terms of a penetration with a 1/4 cone defined by JIS K2220. Gel is suitable. In addition, when the penetration exceeds 200, the form as a silicone gel cured product cannot be maintained and it flows, which is not appropriate.

  Next, a silicone rubber adhesive that is cured by a fixed hydrosilylation reaction that is preliminarily formed into a tape or string shape is placed on the outer periphery of a panel or sheet that has been coated / cured with a liquid silicone rubber or gel composition. To do.

The silicone rubber adhesive (composition) cured by the hydrosilylation reaction used is
(D) The following average composition formula (3)
R ¹¹ _X SiO _{(4-X) / 2} (3)
(In the formula, R ¹¹ is an unsubstituted or substituted monovalent hydrocarbon group, and 0.001 to 1.0 mol% in R ¹¹ is an alkenyl group. X is a positive value of 1.95 to 2.05. Number.)
100 parts by mass of an organopolysiloxane containing at least two alkenyl groups in one molecule represented by
(E) Reinforcing silica: 5-200 parts by mass,
(F) platinum-based catalyst: effective amount,
(G) Organohydrogenpolysiloxane containing at least two hydrogen atoms bonded to silicon atoms in one molecule: The ratio of hydrogen atoms bonded to silicon atoms to one alkenyl group in component (D) is 0 A silicone rubber adhesive (composition) characterized in that an amount of 3 to 10 is an essential component.

The organopolysiloxane of component (D) constituting the silicone rubber adhesive of the present invention has the following average composition formula (3)
R ¹¹ _X SiO _{(4-X) / 2} (3)
(In the formula, R ¹¹ is an unsubstituted or substituted monovalent hydrocarbon group, and 0.001 to 1.0 mol% in R ¹¹ is an alkenyl group. X is a positive value of 1.95 to 2.05. Number.)
An organopolysiloxane containing at least two alkenyl groups in one molecule. In this case, R ¹¹ is an alkyl group such as a methyl group, an ethyl group, a propyl group or a butyl group, a cycloalkyl group such as a cyclohexyl group, an alkenyl group such as a vinyl group, an allyl group, a butenyl group or a hexenyl group, or a phenyl group. An aryl group such as a tolyl group, an aralkyl group such as a β-phenylpropyl group, or a chloromethyl group in which part or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with a halogen atom, a cyano group, The same or different, preferably 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms unsubstituted or substituted monovalent hydrocarbon group selected from a fluoropropyl group, a cyanoethyl group and the like. x needs to be a positive number of 1.95 to 2.05, more preferably a positive number of 1.98 to 2.02. When x is out of the above range, difficulties arise when synthesizing an organopolysiloxane having a degree of polymerization of 100 or more.

The organopolysiloxane of component (D) used in the present invention has its molecular chain end blocked with a trimethylsilyl group, dimethylvinylsilyl group, dimethylhydroxysilyl group, methyldivinylsilyl group, trivinylsilyl group, or the like. Can do. Preferably, it has at least one vinyl group at the end of the molecular chain. In the present invention, this organopolysiloxane must have at least two alkenyl groups in one molecule, and 0.001 to 1.0 mol%, particularly 0.01 to 0.5 mol, of R ^11. % Is preferably an alkenyl group, in particular a vinyl group. Furthermore, the degree of polymerization of the organopolysiloxane needs to be 100 or more in order for the cured product of the resulting composition to obtain sufficient mechanical strength, preferably 100 to 10,000, more preferably 2. , 10,000 to 10,000. Component (D) may be used alone or in combination of two or more different substituents and polymerization degrees.

Next, the reinforcing silica as the component (E) is used for the purpose of obtaining a silicone rubber having excellent mechanical strength. The specific surface area (BET method) for purposes 50 m ² / g or more, it is necessary and preferably 50 to 800 m ² / g, more preferably 100 to 400 m ² / g. When the specific surface area is less than 50 m ² / g, the mechanical strength of the molded product decreases. Examples of such reinforcing silica include dry silica (fumed silica), precipitated silica, and hydrophobic silica whose surfaces are surface-treated with organopolysiloxane, organopolysilazane, chlorosilane, alkoxysilane, and the like. This reinforcing silica may be used in combination of two or more, such as a combination of dry silica and precipitated silica. Dry silica and surface-treated silica are preferred. If the amount of the reinforcing silica added is too small relative to 100 parts by weight of the organopolysiloxane (D), sufficient reinforcing effect will not be obtained. Since the strength of the silicone rubber also decreases, it is 5 to 200 parts by mass, preferably 20 to 100 parts by mass, particularly preferably 30 to 80 parts by mass.

  The platinum-based catalyst of component (F) is the same as component (C) above, and the amount of these catalysts added is a catalytic amount, usually 0.1 to 1,000 ppm in terms of platinum-based metal amount. However, the range of 1 to 300 ppm is suitable. If it is less than 0.1 ppm, the crosslinking reaction is not sufficiently accelerated and curing is insufficient. On the other hand, addition of more than 1,000 ppm has little influence on the reactivity and is uneconomical.

  The amount of organohydrogenpolysiloxane having at least two hydrogen atoms bonded to silicon atoms in one molecule of component (G) is such that hydrogen bonded to silicon atoms with respect to one alkenyl group in component (D). The range in which the atomic ratio is 0.3 to 10 is appropriate, and the range in which the ratio is preferably 0.5 to 5 is appropriate. If there are few SiH groups, crosslinking may not be sufficient, and sufficient mechanical strength may not be obtained, and if there are many SiH groups, physical properties after curing will deteriorate, especially heat resistance and compression set will deteriorate significantly. There are things to do.

  In the silicone rubber adhesive, in addition to the above components, if necessary, the above-mentioned adhesion promoter and adhesion promoter, further non-reinforcing silica such as pulverized quartz and diatomaceous earth, acetylene black, furnace black, Carbon black such as channel black, fillers such as calcium carbonate, polymethylvinylsiloxane cyclic compounds, platinum catalyst inhibitors such as acetylene alcohol, and various additives such as coloring agents, heat resistance improvers, flame retardant improvers, etc. It is optional to add diphenylsilanediol, various alkoxysilanes, carbon functional silanes, silanol group-containing low-molecular siloxanes, etc. as dispersants for fillers and fillers.

  The silicone rubber adhesive is applied and formed in a frame shape on the outer peripheral part of either the front panel, the back panel or the sheet in an uncured state. It is preferable to use a method such as processing the product into a shape and arranging it along the outer periphery of the panel or sheet, or arranging it in the form of a square ring that matches the panel or sheet in advance. Adopted, but not limited to these.

  As a method for processing the silicone rubber adhesive of the present invention as described above, a processing machine used for molding a normal silicone rubber composition can be used. Specific examples include an extruder, a press machine, a calendar roll, and the like provided with a T die or a deformed die, and continuous molding using an extruder is preferable.

  The silicone rubber adhesive must retain its shape before curing, and therefore the plasticity of the silicone rubber adhesive is within the range of 100 to 600 as measured with a Williams plasticity meter at 23 ° C. Is preferred. This is because, when the plasticity is less than 100, the shape retention or the shape retention after molding of the silicone rubber adhesive into an uncured fixed-shaped form is lowered, and an arbitrary shape can be obtained. Because it becomes difficult. In addition, when the plasticity of the silicone rubber adhesive exceeds 600, it is difficult to remove bubbles remaining at the interface when the adhesive is attached to the adherend. Furthermore, it is because it will be in the rough state where an edge part and the surface will rise up when performing extrusion molding.

  After the silicone rubber adhesive formed as described above is arranged in a frame shape on the front panel or the back panel or sheet, the solar cell strings are arranged on the silicone rubber adhesive layer on the panel or sheet. In solar cell elements, one or two types of silicon materials selected from single crystal silicon or polycrystalline silicon are used to form solar cell elements, and solar cell strings connect the solar cell elements with tab wires. It is a thing. Moreover, when arrange | positioning the said photovoltaic cell string on the silicone rubber or gel layer of a back side panel, it arrange | positions with the front side panel turned down and the incident surface side of the photovoltaic cell element on the silicone rubber or gel layer on it. In the case where the back side panel or sheet is placed on the silicone rubber or gel layer, the back side panel or sheet is placed on the bottom, and the solar cell element incident surface side is placed on the silicone rubber or gel layer on the back side panel or sheet. . After the panel or sheet on which the solar cell strings are arranged is installed in a vacuum laminator device, the other panel or sheet is arranged with the silicone rubber or gel layer on the lower side and the panel or sheet on which the solar cell strings are arranged A gap is provided between them.

Next, after removing the air between the silicone rubber or gel layer and the solar cell element or between the silicone rubber or gel layers under reduced pressure, the silicone rubber is heated to 60 to 200 ° C. and arranged in a frame shape. The solar cell strings are embedded and sealed in both the silicone rubber or gel layer by pressure bonding between the adhesive, the silicone rubber or gel layer and the solar cell element, and between the silicone rubber or gel layers. At the same time, the silicone rubber adhesive is cured, and the front panel and the back panel or sheet are joined together, thereby obtaining a solar cell module.
The degree of decompression is preferably -0.06 to -0.10 MPa, particularly preferably -0.07 to -0.10 MPa. The heating and pressing conditions are also selected as appropriate, but it is preferable to press at 5 to 30 minutes at atmospheric pressure after decompression for 3 to 15 minutes under heating at 70 to 150 ° C., particularly 100 to 130 ° C.

  Hereinafter, the present invention will be described in detail with reference to examples and comparative examples. In the examples, “part” represents “part by mass”, “%” represents “mass%”, and “Vi” represents “vinyl group”. The methods for measuring viscosity, plasticity, hardness and penetration are as described above.

[Example 1]
[Silicone rubber adhesive (1)]
100 parts of organopolysiloxane consisting of 99.825 mol% dimethylsiloxane units, 0.15 mol% methylvinylsiloxane units and 0.025 mol% dimethylvinylsiloxane units and having an average degree of polymerization of about 8,000, and a specific surface area of 200 m ² / 40 parts of fumed silica (manufactured by Nippon Aerosil Co., Ltd.), having silanol groups at both ends as a dispersant, and having an average polymerization degree of 15 and a viscosity by an Ostwald viscometer at 25 ° C. of 30 mm ² / s 10 parts of dimethylpolysiloxane was kneaded with a kneader and heat-treated at 160 ° C. for 2 hours to prepare a base compound. For 100 parts of this base compound, 0.2 part of a platinum siloxane solution (10% product), 0.05 part of 1-ethynylcyclohexane-1-ol, trimethylsiloxy group-blocked dimethylsiloxane / methylhydrogensiloxane 1.0 part of a copolymer (Si—H amount: 0.007 mol / g) was blended to obtain a silicone rubber adhesive (1) having a plasticity of 280 at 23 ° C.
When used, the unvulcanized silicone rubber adhesive (1) compound was formed into a tape shape having a width of 10 mm and a thickness of 2 mm by an extrusion method.

[Panel (1) coated / cured with liquid silicone gel composition]
1% as a platinum atom in 100 parts of dimethylpolysiloxane having both molecular chain ends blocked with vinyldimethylsiloxy groups, viscosity at 23 ° C. of 1,000 mPa · s, and Vi content of 0.012 mol / 100 g 0.05 part of dimethylpolysiloxane solution of vinyl chloroplatinic acid complex containing 0.1 part of 1,3,5,7-tetramethyl-1,3,5,7-tetravinyltetrasiloxane as addition reaction control agent Was added and mixed uniformly, and then 1.2 parts of methylhydrogenpolysiloxane having Si—H groups in the side chain (Si—H amount: 0.0055 mol / g) was added to prepare a preparation solution (total Si— H / Si-Vi (p) = 0.5). This prepared solution is applied to a white tempered glass with a thickness of 340mm x 360mm and a thickness of 3.2mm with a masking tape around 10mm, then applied to a thickness of 500μm, and cured by heating at 120 ° C for 10 minutes to apply silicone. A film was obtained and used as a surface panel. The silicone had a penetration of 50.

[Panel (2) coated / cured with liquid silicone rubber composition]
131 parts of dimethylpolysiloxane having both molecular chain ends blocked with vinyldimethylsiloxy groups, viscosity at 23 ° C. of 1,000 mPa · s, and Vi content of 0.012 mol / 100 g, (CH ₃ ) ₃ SiO Resin copolymer comprising _1/2 units, (CH ₂ ═CH) (CH ₃ ) ₂ SiO _1/2 units and SiO ₂ units [[(CH ₃ ) ₃ SiO _1/2 units and (CH ₂ ═CH ) (CH ₃ ) ₂ SiO _1/2 units and total] / SiO ₂ units = 0.8 (molar ratio), Vi content = 0.0005 mol / g] 50 parts, platinum chloride containing 1% as platinum atom 0.3 part of a dimethylpolysiloxane solution of an acid vinylsiloxane complex, 0.2 part of triallyl isocyanurate, 0.05 part of a reaction control agent ethynylcyclohexanol, an organohydrogen represented by the following chemical formula (4) Rokisan 25 parts, was mixed uniformly organohydrogensiloxane 2.5 parts represented by the following formula (5) (total Si-H / Si-Vi (q) = 2.0). After making a bank with masking tape to a white plate heat-strengthened glass of 340 mm x 360 mm and thickness 3.2 mm with a masking tape of 10 mm, apply it to a thickness of 500 μm, heat cure at 120 ° C. for 10 minutes to obtain a silicone coating film, This was used as the back panel. The silicone had a durometer type A20.

〔modularization〕
The masking tape of the panel (1) and the panel (2) is removed, and a tape-shaped silicone rubber adhesive (1) having a thickness of 2 mm is disposed around the panel (2) (the portion where the silicone is not placed) The battery cell strings are placed, and a laminated body is formed with the silicone coating surface of the panel (1) on the top side of the solar cell strings, and this laminated body is put in a vacuum laminator tank and depressurized at −120 ° C. for 5 minutes (− Thereafter, pressing was performed for 15 minutes.

[Evaluation method]
After modularization with a vacuum laminator, it was visually confirmed whether or not the solar cell strings were completely sealed with the silicone coating film. Further, the module was placed in a constant temperature and humidity chamber having a temperature of 85 ° C. and a humidity of 85%, and the state after 1,000 hours was again visually confirmed. The results are shown in Table 1.

[Example 2]
[Sheet (1) coated / cured with liquid silicone rubber composition]
131 parts of dimethylpolysiloxane with both ends of the molecular chain blocked with vinyldimethylsiloxy groups, a viscosity at 23 ° C. of 5,000 mPa · s, and a Vi content of 0.006 mol / 100 g, (CH ₃ ) ₃ SiO Resin copolymer comprising _1/2 units, (CH ₂ ═CH) (CH ₃ ) ₂ SiO _1/2 units and SiO ₂ units [[(CH ₃ ) ₃ SiO _1/2 units and (CH ₂ ═CH ) (Total with (CH ₃ ) ₂ SiO _1/2 unit] / SiO ₂ unit = 0.8 (molar ratio), vinyl group content = 0.085 mol / g] 50 parts, chloride containing 1% as platinum atom 0.3 part of a dimethylpolysiloxane solution of a vinyl platinate siloxane complex, 0.2 part of triallyl isocyanurate, 0.05 part of a reaction control agent ethynylcyclohexanol, an organohydrogen represented by the above chemical formula (4) 25 parts of siloxane, 4.0 parts of organohydrogensiloxane represented by the above chemical formula (5) and 0.5 part of a compound represented by the following chemical formula (6) (KAYARAD R604 manufactured by Nippon Kayaku Co., Ltd.) are uniformly mixed. (Total Si—H / Si—Vi (q) = 2.0). A back sheet of 600 mm × 1,600 mm and a thickness of 350 μm (manufactured by M Package, PTD250) is coated to a thickness of 300 μm and cured by heating at 120 ° C. for 15 minutes to obtain a silicone coating film, which is used as a back panel. . The silicone had a durometer type A20.

〔modularization〕
The masking tape on the panel (1) and the sheet (1) is removed, and a tape-shaped silicone rubber adhesive (1) having a thickness of 2 mm is placed around the sheet (1) (the portion where no silicone is placed). The battery cell strings are placed, and a laminated body is formed with the silicone coating surface of the panel (1) on the top side of the solar cell strings, and this laminated body is put in a vacuum laminator tank and depressurized at −120 ° C. for 5 minutes (− Thereafter, pressing was performed for 15 minutes.

[Evaluation method]
After modularization with a vacuum laminator, it was visually confirmed whether or not the solar cell strings were completely sealed with the silicone coating film. Further, the module was placed in a constant temperature and humidity chamber having a temperature of 85 ° C. and a humidity of 85%, and the state after 1,000 hours was again visually confirmed. The results are shown in Table 1.

[Comparative Example 1]
〔modularization〕
It is the same except having used the butyl rubber-type thermoplastic agent ("M-155P" by Yokohama Rubber Co., Ltd.) instead of the silicone rubber adhesive described in Example 1. The results are shown in Table 1.

Claims (7)

(1) A step of preparing a front side panel in which a liquid silicone rubber or gel composition is applied to one side of a transparent panel on which sunlight is incident and cured to form a silicone rubber or gel layer.
(2) A step of preparing a back side panel or sheet in which a liquid silicone rubber or gel composition is applied to one side of a panel or sheet opposite to the incidence of sunlight and cured to form a silicone rubber or gel layer;
(3) A step of forming an uncured silicone rubber adhesive layer that is cured by a hydrosilylation reaction in the form of a frame on the outer peripheral portion of the surface on the silicone rubber or gel layer forming side of at least one of the front panel and the back panel or sheet;
(4) A solar battery cell string in which a plurality of solar battery elements made of a semiconductor substrate are connected between the silicone rubber or gel layer of the front panel and the silicone rubber or gel layer of the back panel or sheet is sandwiched between 60 and 200. The front panel and the back panel or sheet are sandwiched between the front panel and the rear panel under vacuum at a temperature of C to embed and seal the solar cell strings in both silicone rubbers or gel layers, and to cure the silicone rubber adhesive layer. The manufacturing method of the solar cell module characterized by including the process of joining a front side panel, a back side panel, or a sheet | seat.   The manufacturing method according to claim 1, wherein the hardness of the silicone rubber or gel layer is 50 or less by a type A durometer defined by JIS K6253 and 200 or less by a penetration by a 1/4 cone defined by JIS K2220. . Liquid silicone rubber or gel composition
(A) The following average composition formula (1)
R _a R ¹ _b SiO _{(4-ab) / 2} (1)
(In the formula, R is independently an alkenyl group, R ¹ is independently an unsubstituted or halogen atom-substituted monovalent hydrocarbon group not containing an aliphatic unsaturated bond, and a is from 0.0001 to 0.2. And b is a positive number of 1.7 to 2.2, where a + b is 1.9 to 2.4.)
An organopolysiloxane having at least one alkenyl group bonded to a silicon atom in one molecule represented by:
(B) Organohydrogenpolysiloxane having at least two hydrogen atoms bonded to silicon atoms in one molecule: The number of silicon atom-bonded hydrogen atoms in this component is 0 per silicon atom-bonded alkenyl group in component (A). The production method according to claim 1, which is an addition-curable liquid silicone rubber or gel composition using a hydrosilylation reaction containing an amount of 3 to 10 and (C) a platinum-based catalyst: an effective amount.   The outer peripheral part of the front side panel and the outer peripheral part of the back side panel or sheet are made into a silicone rubber or gel layer non-formed part, and the silicone rubber adhesive layer is arranged on the non-formed part. The manufacturing method as described in.   The manufacturing method according to any one of claims 1 to 4, wherein the silicone rubber adhesive layer has a plasticity in an uncured state at 23 ° C in a range of 100 to 600 as measured by a Williams plasticity meter. Silicone rubber adhesive
(D) The following average composition formula (3)
R ¹¹ _X SiO _{(4-X) / 2} (3)
(In the formula, R ¹¹ is an unsubstituted or substituted monovalent hydrocarbon group, and 0.001 to 1.0 mol% in R ¹¹ is an alkenyl group. X is a positive value of 1.95 to 2.05. Number.)
100 parts by mass of an organopolysiloxane containing at least two alkenyl groups in one molecule represented by
(E) Reinforcing silica: 5-200 parts by mass,
(F) platinum-based catalyst: effective amount,
(G) Organohydrogenpolysiloxane containing at least two hydrogen atoms bonded to silicon atoms in one molecule: The ratio of hydrogen atoms bonded to silicon atoms to one alkenyl group in component (D) is 0 The manufacturing method of any one of Claims 1-5 which uses the quantity used as 3-10 pieces as an essential component.   Silicone rubber adhesive is formed into a string shape in advance, and this is arranged in a frame shape along the outer periphery of the surface panel or the back panel or the outer periphery of the sheet, or is formed into a rectangular frame shape in advance. The manufacturing method of any one of Claims 1-6 which formed the silicone rubber adhesive layer by arrange | positioning in the outer peripheral part or the outer peripheral part of a back side panel or a sheet | seat.