JP2013084801A - Resin composition for solar cell sealing material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition for a solar cell sealing material, having good transparency, improving initial conversion efficiency of a solar cell, preventing reduction in wavelength conversion effect even when time elapses, and further suppressing reduction in adhesion with a protective member after a lapse of time by capturing acid associated to resin deterioration; and a solar cell sealing material.SOLUTION: A resin composition for a solar cell sealing material is characterized by comprising a layered composite metal compound (A), a compound (C) represented by the following general formula (1), and an ethylene copolymer (D).

Description

  The present invention relates to a resin composition for a solar cell encapsulant used for a solar cell encapsulant.

  In recent years, the photovoltaic power generation system has been gaining attention all over the world as a clean and sustainable energy system from the viewpoint of global warming countermeasures and replacement of fossil fuels that are feared to be depleted. Therefore, the solar cell market is rapidly expanding at an annual growth rate of nearly 30%. Currently, the mainstream photovoltaic power generation is composed of silicon-based solar cell modules such as crystalline silicon and amorphous silicon, and compound semiconductor-based solar cell modules such as CdTe and CIGS, and peripheral devices. Reduction of power generation cost is the biggest issue. Although power generation costs have decreased significantly over the past few years, current power generation costs are still relatively high compared to other energies, and technological developments such as higher efficiency and longer life of solar cells have been made. It has been demanded.

  On the other hand, to improve the efficiency of the solar cell module, it is necessary to improve various performances such as light receiving property, transparency, and electrical characteristics, and these performances are also required for a sealing material for protecting the power generation element from the environment. (See Patent Documents 1, 2, and 3).

  However, since many sealing materials use a resin having high transparency from the beginning, it is difficult to significantly improve the transparency. In addition, the crystalline silicon power generation element has low spectral sensitivity in the ultraviolet region of sunlight due to its characteristics, and sunlight cannot be effectively used. Therefore, Patent Documents 4 and 5 disclose a sealing material and a solar cell in which an organic metal complex that absorbs ultraviolet light and emits light in the visible light region is blended to improve conversion efficiency.

JP 2000-183381 A JP 2009-152543 A JP 2008-153520 A International Publication No. 2008/047427 JP 2010-258293 A

  However, in Patent Documents 4 and 5, since the ligand of the organometallic complex does not have light resistance, the conversion efficiency is rapidly decreased by continuous light irradiation, so that it is not practical.

  The present invention has good transparency, improves the initial conversion efficiency of the solar cell, hardly reduces the wavelength conversion effect over time, and further protects with time by capturing acid accompanying resin degradation. It aims at providing the resin composition for solar cell sealing materials with few fall of adhesiveness with a member, and a solar cell sealing material.

  The present invention is a resin composition for a solar cell encapsulant comprising at least a layered composite metal compound (A), a compound (C) represented by the following general formula (1), and an ethylene copolymer (D). is there.

General formula (1)

(In the formula, R ₁ is a halogen atom, an alkyl group having 1 to 12 carbon atoms which may have a substituent, an aryl group which may have a substituent, or an alkoxy group which may have a substituent. Or R ₂ , R ₃ , R ₆ , R ₇ , R ₈ may each independently have a hydrogen atom, a halogen atom, a hydroxy group, or a substituent. R ₄ represents an alkyl group having 1 to 12 carbon atoms, an aryl group that may have a substituent, an alkoxy group that may have a substituent, or an amino group that may have a substituent. , R ₅ and R ₉ are each independently a hydrogen atom, a halogen atom, an optionally substituted alkyl group having 1 to 12 carbon atoms, or an optionally substituted aryl group, or a substituent. Represents an optionally substituted alkoxy group.)

The present invention having the above structure forms a complex by allowing the layered composite metal compound (A) and the compound (C) having a specific structure to coexist, and emits light in the visible region by absorbing ultraviolet rays. By this wavelength conversion, the initial conversion efficiency of the solar battery can be improved by increasing the amount of light received by the solar battery cell. In addition, since compound (C) has a ketoenol tautomer, it is rich in light resistance and can maintain the wavelength conversion effect for a long period of time. Furthermore, the layered composite metal compound (A) reduces the deterioration of the power generation element of the solar cell by neutralizing the water that has penetrated into the solar cell sealing material and the acid generated by resin degradation, etc. The decline is suppressed.

  According to the present invention, the transparency is good, the initial conversion efficiency of the solar cell is improved, the wavelength conversion effect is less likely to decrease over time, and further, the time passes by capturing the acid accompanying the resin deterioration. It was possible to provide a resin composition for a solar cell encapsulant with little decrease in adhesion to the protective member even after the treatment.

It is typical explanatory drawing which shows an example of a solar cell module sample. It is explanatory drawing for showing the sample for an endurance test. It is explanatory drawing for showing the sample for an endurance test. It is explanatory drawing for showing the sample for an endurance test.

  First, the present invention will be described in detail. In the present specification, the description of “any number A or more and any number B or less” and “any number A to any number B” is a range larger than the number A and the number A, and the number B And a range smaller than the number B.

  This invention is a resin composition for solar cell sealing materials containing a layered composite metal compound (A), the compound (C) represented by the following general formula (1), and an ethylene copolymer (D). . And it functions as a fluorescent material which has a wavelength conversion effect by combining a layered composite metal compound (A) and the compound (C) represented by General formula (1). Here, the fluorescent material refers to a compound that absorbs ultraviolet rays and emits fluorescence, and the absorption wavelength and emission wavelength depend on the metal species of the metal compound and the organic compound structure serving as a ligand. The wavelength conversion effect refers to converting a certain wavelength to another wavelength. In the present invention, it refers to converting ultraviolet light with low spectral sensitivity to light with high sensitivity to the visible part. The wavelength conversion effect is determined by the absorption wavelength, emission wavelength, emission intensity, and the amount of light received by the solar cell element, but absorbs ultraviolet rays with a small power generation contribution rate from sunlight and emits light in the visible long wavelength region. A large Stokes shift is preferable.

  Inorganic phosphors, organic phosphors, organometallic complexes and the like are known as compounds having a wavelength conversion function. However, many inorganic phosphors have a high refractive index. Therefore, when added to the ethylene copolymer, the difference in refractive index from the ethylene copolymer increases, causing light scattering, increasing reflection on the surface of the power generation element, and lowering conversion efficiency. In addition, the organic phosphor deteriorates due to continuous irradiation with ultraviolet rays. This deterioration occurs similarly in the ligand of the organometallic complex, and the wavelength conversion function cannot be maintained for a long time. In the case of an organometallic complex, depending on the metal ion species, it has a catalytic action that promotes the auto-oxidation reaction of the resin and degrades the resin and other additives. The deterioration effect due to metal increases in proportion to temperature and humidity. Furthermore, since deterioration due to heat also acts, it was extremely difficult to use it for solar cell applications.

  Therefore, the present invention combines a layered composite metal compound (A) or a fired product thereof with a specific compound (C) even in a state where it is exposed to ultraviolet rays for a long period of time such as a solar cell encapsulant. Therefore, the wavelength conversion effect can be maintained for a long time because there is little deterioration due to ultraviolet light. Furthermore, the present inventors also found an effect of capturing an acid accompanying resin deterioration and suppressing a decrease in adhesion with a protective member such as a back surface protective sheet over a long period of time.

It is important that the layered composite metal compound (A) of the present invention is a layered composite metal compound.
Specifically, hydrotalcite, zeolite and the like are preferable. Among these, hydrotalcite is preferable. The layered composite metal compound is a compound in a layered form having interlayer ion exchange properties and neutralization reactivity with acids. And by including these in the solar cell module, water that has penetrated into the solar cell encapsulant and acid generated by hydrolysis of the ethylene vinyl acetate copolymer due to deterioration, etc. are taken in between the layers, and also neutralized Produces an effect of preventing deterioration of the solar cell encapsulant and the power generation element (hereinafter also referred to as an acid / water trapping effect). The acid / water trapping effect is determined by the charge density of ions entering the interlayer, and anions having a higher valence and a smaller ion radius are more easily taken into the interlayer. The effects of the layered composite metal compound in the present invention can improve transparency and increase the efficiency of the acid / water trapping effect, and can suppress the decrease in adhesion and the conversion efficiency with the protective member over time.

  The layered composite metal compound (A) is more preferably a layered composite metal compound represented by the following general formula (2) or general formula (3).

Mg _1-a · Al _a (OH) ₂ · An ^n- _{a / n} · cH ₂ O General formula (2)
(0.2 ≦ a ≦ 0.35, 0 ≦ c ≦ 1, An: n-valent anion)

_{(M d Mg 1-d)} 1-e · Al e (OH) 2 · An n- e / n · fH 2 O Formula (3)
(M represents a metal selected from Zn and Ca, and d and e are the formulas 0 ≦ d ≦ 1, 0.2 ≦ e ≦ 0.35, 0 ≦ f ≦ 1, An: n-valent anion)

In the general formula (2), the Al content ratio a is preferably 0.2 to 0.35. By becoming 0.2 or more, it becomes easy to produce a layered composite metal compound. On the other hand, by being 0.35 or less, the difference in refractive index from the ethylene copolymer (A) is reduced, and the transparency is more easily improved. The type of the anion An ⁿ⁻ is not particularly limited, and examples thereof include hydroxide ions, carbonate ions, silicate ions, organic carboxylate ions, organic sulfonate ions, and organic phosphate ions. The index a in the general formula (2) was obtained by dissolving the layered composite metal compound with an acid and analyzing with a “plasma emission spectroscopic analyzer SPS4000 (Seiko Electronics Co., Ltd.)”.

In the general formula (3), the Zn and Ca content ratio d is preferably 0 to 1. The Al content ratio e is preferably 0.2 to 0.35. By becoming 0.2 or more, it becomes easy to produce a layered composite metal compound. By being 0.35 or less, the refractive index difference from the ethylene copolymer (A) is reduced, and the transparency is more easily improved. The type of the anion An ⁿ⁻ is not particularly limited, and examples thereof include hydroxide ions, carbonate ions, silicate ions, organic carboxylate ions, organic sulfonate ions, and organic phosphate ions.

  The metal of the layered composite metal compound (A) is preferably magnesium, aluminum, zinc, or calcium, more preferably magnesium or aluminum, from the viewpoint of preventing resin deterioration due to the metal. If there is a resin deterioration effect due to the metal, it is difficult to maintain the wavelength conversion effect for a long time because the metal released in the solar cell encapsulant promotes the oxidation of the resin and the deterioration of the resin and fluorescent material. There is a risk of becoming.

  In the present invention, the layered composite metal compound (A) is preferably a fired product (B) of the layered composite metal compound (A). Moreover, 150-850 degreeC is preferable for a calcination temperature. This fired product (B) exhibits a higher acid / water scavenging effect than the layered composite metal compound. In addition, the baked product captures acid and water, the chemical composition changes, and the refractive index decreases, so the difference in refractive index from the ethylene copolymer decreases, so the transparency tends to improve over time. is there.

  An example is given and demonstrated about the manufacturing method of a layered composite metal compound (A).

  After mixing at least one of an aqueous magnesium salt solution, an aqueous zinc salt solution, an aqueous calcium salt solution, an alkaline aqueous solution containing an anion, and an aqueous aluminum salt solution to obtain a mixed solution having a pH in the range of 8 to 14, the mixed solution is It can be obtained by aging in the temperature range of 60-100 ° C.

  The pH during the ripening reaction is preferably 9-14, more preferably 10-14. When pH is less than 9, there exists a possibility that it may become a layered composite metal compound with non-uniform plate surface diameter and thickness.

  If the aging temperature is less than 60 ° C. or 100 ° C. or more, there is a possibility that a layered composite metal compound having a non-uniform plate surface diameter may be obtained. A more preferable aging temperature is 70 to 100 ° C.

The aging time for the aging reaction of the layered composite metal compound is not particularly limited, but is preferably about 2 to 24 hours, for example. In the case of less than 2 hours, there is a possibility that a layered composite metal compound having a non-uniform plate surface diameter or thickness may be obtained. Aging over 24 hours is not economical.

  The alkaline aqueous solution containing the anion is preferably a mixed alkaline aqueous solution of an aqueous solution containing an anion and an aqueous alkali hydroxide solution.

  As an aqueous solution containing an anion, aqueous solutions such as sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, organic carboxylate, organic sulfonate, and organic phosphate are preferable.

  As the alkali hydroxide aqueous solution, sodium hydroxide, potassium hydroxide, ammonia, urea aqueous solution and the like are preferable.

  As the metal salt aqueous solution in the present invention, a metal sulfate aqueous solution, a metal chloride aqueous solution, a metal nitrate aqueous solution and the like can be used, and a magnesium chloride aqueous solution is preferable. Further, a slurry of metal oxide powder or metal hydroxide powder may be substituted.

  As the aluminum salt aqueous solution in the present invention, an aluminum sulfate aqueous solution, an aluminum chloride aqueous solution, an aluminum nitrate aqueous solution and the like can be used, and an aluminum sulfate aqueous solution and an aluminum chloride aqueous solution are preferable. A slurry of aluminum oxide powder or aluminum hydroxide powder may be substituted.

  The order of mixing the alkaline aqueous solution containing an anion, at least one of magnesium, zinc and calcium and aluminum is not particularly limited, and each aqueous solution or slurry may be mixed simultaneously. Preferably, an aqueous solution or slurry in which magnesium, zinc, calcium and aluminum are mixed in advance is added to an aqueous alkaline solution containing an anion.

  Moreover, when adding each aqueous solution, you may carry out either when adding this aqueous solution at once, or when dripping continuously.

  The pH of the layered composite metal compound represented by the general formulas (2) and (3) is preferably 8.0 to 10.0. The neutralization efficiency with an acid improves more because pH becomes 8.0 or more. On the other hand, when the pH is 10.0 or less, the metal is not eluted and the ethylene vinyl acetate copolymer is hardly deteriorated. The pH of the layered composite metal compound was measured by weighing 5 g of a sample into a 300 ml Erlenmeyer flask, adding 100 ml of boiled pure water, heating and holding the boiled state for about 5 minutes, then plugging it and allowing it to cool to room temperature. Add water corresponding to the weight loss, plug again, shake for 1 minute, let stand for 5 minutes, then measure the pH of the resulting supernatant according to JIS Z8802-7, and obtain the obtained value as a layered composite The pH of the metal compound was used.

  In the production of the fired product (B), the layered composite metal compound (B) is preferably fired at 150 to 850 ° C, more preferably 200 ° C to 750 ° C. The firing time may be adjusted according to the firing temperature, but is preferably 1 to 24 hours, and more preferably 1 to 10 hours. The atmosphere during firing may be an oxidizing atmosphere or a non-oxidizing atmosphere, but it is better not to use a gas having a strong reducing action such as hydrogen.

  In the present invention, it is important that the compound (C) represented by the general formula (1) has a structure capable of taking a ketoenol tautomer. It is presumed that compound (C) realizes extremely good light resistance by changing ultraviolet rays into heat due to the presence of ketoenol tautomers. Therefore, the wavelength conversion action can be maintained even when exposed to ultraviolet rays for a long time. The central skeleton of the compound is preferably a benzophenone skeleton from the viewpoint of a light absorption region and coordination ability. Further, the ketoenol tautomer is preferable from the viewpoint of stability because it is less likely to cause distortion in the molecule because of proton transfer between the carbonyl group and the β-position hydroxy group. On the other hand, when it does not have a structure capable of taking a ketoenol tautomer, it does not have a mechanism for converting ultraviolet light into heat (photothermal relaxation mechanism), and it tends to be difficult to obtain light resistance. In addition, when a metal is coordinated to a site capable of taking ketoenol tautomerism, the function of converting light into heat does not act and it is difficult to obtain light resistance. Therefore, in the present invention, a structure in which a steric hindrance group is introduced at the 3-position of the benzophenone skeleton and no metal is coordinated to the ketoenol tautomerism site is preferable.

The compound (C) is represented by the following general formula (1), wherein R ₁ may have a halogen atom, an alkyl group having 1 to 12 carbon atoms which may have a substituent, or a substituent. Represents a good aryl group, an optionally substituted alkoxy group, or an optionally substituted amino group, preferably a methyl group, an ethyl group, an i-propyl group, or a t-butyl group. More preferably, they are i-propyl group and t-butyl group. R ₂ , R ₃ , R ₆ , R ₇ and R ₈ each independently have a hydrogen atom, a halogen atom, a hydroxy group, an alkyl group having 1 to 12 carbon atoms which may have a substituent, or a substituent. Represents an optionally substituted aryl group, an optionally substituted alkoxy group, or an optionally substituted amino group, preferably a hydrogen atom, a hydroxyl group, a methoxy group, an ethoxy group, a hexoxy group, Dodoxy group. R ₄ , R ₅ , and R ₉ are each independently a hydrogen atom, a halogen atom, an optionally substituted alkyl group having 1 to 12 carbon atoms, or an optionally substituted aryl group, or a substituted group. Represents an alkoxy group which may have a group, and preferably a hydrogen atom.
General formula (1)

  In the present invention, the layered composite metal compound (A) is 0.05 parts by weight or more and 15 parts by weight or less, and the compound (C) is 0.01 parts by weight or more and 10 parts by weight with respect to 100 parts by weight of the ethylene copolymer (D). It is preferable to use up to parts by weight.

Similarly, when using the fired product of the layered composite metal compound, 0.05 part by weight or more and 15 parts by weight or less of the fired product of the layered composite metal compound (B) with respect to 100 parts by weight of the ethylene copolymer (D). The compound (C) is preferably used in an amount of 0.01 parts by weight or more and 10 parts by weight or less.
Moreover, for example, when manufacturing the resin composition for solar cell sealing materials of a high concentration mixing | blending product like a masterbatch, a layered composite metal compound (A) with respect to 100 weight part of ethylene copolymers (D) It is preferable to use 3 to 15 parts by weight and 1 to 10 parts by weight of the compound (C). Manufacturing a solar cell encapsulant using a masterbatch is preferable from the viewpoint of dispersion and handling of the fluorescent material. On the other hand, for example, in the case of a resin composition for a solar cell encapsulant other than a masterbatch, from the viewpoint of transparency, the layered composite metal compound (A) and the compound (C) are added in a total of 0.01 to 1.5 parts by weight. It is preferable to use within a range. If the upper limit of the amount used is exceeded, the transparency becomes insufficient and the initial conversion efficiency may be reduced. If the amount is less than 0.01 part by weight, the wavelength conversion effect may be insufficient.

  The compound (C) used in the present invention is a hydroxybenzophenone compound, specifically, for example, 2,5-dihydroxy-3-t-butylbenzophenone, 2,5-dihydroxy-3-t-butyl-4 ′. -Methoxybenzophenone, 2,5-dihydroxy-3-t-butyl-4'-octoxybenzophenone, 2,5-dihydroxy-3-t-butyl-4'-dodecyloxybenzophenone, 2,4'-dihydroxy-3 -T-butylbenzophenone, 2,4'-dihydroxy-3-t-butyl-4-methoxybenzophenone, 2,4'-dihydroxy-3-t-butyl-4-octoxybenzophenone, 2,4'-dihydroxy- 3-t-butyl-4-dodecyloxybenzophenone, 2,5-dihydroxy-3-benzylbenzopheno 2,5-dihydroxy-3-benzyl-4'-methoxybenzophenone, 2,5-dihydroxy-3-benzyl-4'-octoxybenzophenone, 2,5-dihydroxy-3-benzyl-4'-dodecyloxybenzophenone 2,4′-dihydroxy-3-benzylbenzophenone, 2,4′-dihydroxy-3-benzyl-4-methoxybenzophenone, 2,4′-dihydroxy-3-benzyl-4-octoxybenzophenone, 2,4 ′ -Dihydroxy-3-benzyl-4-dodecyloxybenzophenone, 2,5-dihydroxy-3-i-propylbenzophenone, 2,5-dihydroxy-3-i-propyl-4'-methoxybenzophenone, 2,5-dihydroxy- 3-i-propyl-4'-octoxybenzophenone, 2 5-dihydroxy-3-i-propyl-4'-dodecyloxybenzophenone, 2,4'-dihydroxy-3-i-propylbenzophenone, 2,4'-dihydroxy-3-i-propyl-4-methoxybenzophenone, 2, 4,4′-dihydroxy-3-i-propyl-4-octoxybenzophenone, 2,4′-dihydroxy-3-i-propyl-4-dodecyloxybenzophenone, and the like.

  In the present invention, the ethylene copolymer (D) is a copolymer of two or more monomers, and is not particularly limited as long as at least one of the monomers is an ethylene monomer. Specifically, ethylene vinyl acetate copolymer, ethylene methyl acrylate copolymer, ethylene ethyl acrylate copolymer, ethylene methyl methacrylate copolymer, ethylene ethyl methacrylate copolymer, ethylene vinyl acetate multi-component copolymer. Polymer, ethylene methyl acrylate multi-component copolymer, ethylene ethyl acrylate multi-component copolymer, ethylene methyl methacrylate multi-component copolymer, ethylene ethyl methacrylate multi-component copolymer, etc. From the viewpoint of reducing cell damage and improving transparency and productivity, an ethylene vinyl acetate copolymer having a vinyl acetate content of 15 to 40% is preferable, and more preferably ethylene acetate having a vinyl acetate content of 25 to 35%. Vinyl copolymer.

  In the present invention, the ethylene copolymer (D) preferably has a melt flow rate (hereinafter simply referred to as MFR) of 0.1 to 60 g / 10 min in consideration of moldability, mechanical strength, and the like. 0.5 to 45 g / 10 min is more preferable. The melt flow rate is a numerical value measured according to JIS K7210.

  The resin composition for a solar cell encapsulant of the present invention includes a crosslinking agent, a crosslinking assistant, a silane coupling agent, an ultraviolet absorber, a light stabilizer, an antioxidant, a colorant, a flame retardant, and a dispersant as necessary. It is also possible to add additives such as these. In addition, various additives may be blended together with the ethylene copolymer (D), the layered composite metal compound (A), and the compound (C), or added separately when manufacturing the final molded product. Is also possible.

  The crosslinking agent is used to prevent thermal deformation of the ethylene copolymer under high temperature use. In the case of ethylene copolymers, organic peroxides are generally used. The addition amount is not particularly limited, but 0.05 to 3 parts by weight is used with respect to a total of 100 parts by weight of the ethylene copolymer, the layered metal compound or / and the fired product thereof, and the ketoenol tautomer. preferable. Specific examples include tert-butyl peroxyisopropyl carbonate, tert-butyl peroxy-2-ethylhexyl isopropyl carbonate, tert-butyl peroxyacetate, tert-butylcumyl peroxide, 2,5-dimethyl-2,5-di (Tert-butylperoxy) hexane, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexyne-3, 2,5-dimethyl-2,5-di (Tert-butylperoxy) hexane, 1,1-di (tert-hexylperoxy) -3,3,5-trimethylcyclohexane, 1,1-di (tert-butylperoxy) cyclohexane, 1,1-di (Tert-hexylperoxy) cyclohexane, 1,1-di tert-amylperoxy) cyclohexane, 2,2-di (tert-butylperoxy) butane, methyl ethyl ketone peroxide, 2,5-dimethylhexyl-2,5-diperoxybenzoate, tert-butyl hydroperoxide, p -Mentane hydroperoxide, dibenzoyl peroxide, p-chlorobenzoyl peroxide, tert-butylperoxyisobutyrate, n-butyl-4,4-di (tert-butylperoxy) valerate, ethyl-3,3 -Di (tert-butylperoxy) butyrate, hydroxyheptyl peroxide, dichlorohexanone peroxide, 1,1-di (tert-butylperoxy) 3,3,5-trimethylcyclohexane, n-butyl-4,4- Te t- butyl peroxy) valerate, 2,2-di (tert- butylperoxy) include butane and the like.

  The crosslinking aid is used to efficiently perform the crosslinking reaction, and examples thereof include polyunsaturated compounds such as polyallyl compounds and polyacryloxy compounds. The addition amount is not particularly limited, but 0.05 to 3 parts by weight is used with respect to 100 parts by weight of the total of the ethylene copolymer, the layered metal compound or / and the fired product thereof, and the ketoenol tautomer. Is preferred. Specific examples include triallyl isocyanurate, triallyl cyanurate, diallyl phthalate, diallyl fumarate, diallyl maleate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, and the like.

  Silane coupling agents are used to improve adhesion to protective materials and solar cell elements, and include unsaturated groups such as vinyl groups, acryloxy groups, and methacryloxy groups, and hydrolyzable groups such as alkoxy groups. The compound which has is mentioned. The addition amount is not particularly limited, but 0.05 to 3 parts by weight is used with respect to a total of 100 parts by weight of the ethylene copolymer, the layered metal compound or / and the fired product thereof, and the ketoenol tautomer. preferable. Specific examples include vinyltrichlorosilane, vinyltris (βmethoxyethoxy) silane, vinyltriethoxysilane, vinyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane. , Γ-glycidoxypropylmethyldiethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, γ-aminopropyltriethoxysilane, Examples thereof include N-phenyl-γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, and γ-chloropropyltrimethoxysilane.

  The ultraviolet absorber is used for imparting weather resistance, and examples thereof include benzophenone series, benzotriazole series, triazine series, and salicylic acid ester series. The addition amount is not particularly limited, but 0.01 to 3 parts by weight is used with respect to a total of 100 parts by weight of the ethylene copolymer, the layered metal compound or / and the fired product thereof, and the ketoenol tautomer. preferable. Specific examples include 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-2′-carboxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-n-dodecyloxybenzophenone, 2-hydroxy-4-n-octadecyloxybenzophenone, 2-hydroxy-4-benzyloxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, 2-hydroxy-5-chlorobenzophenone, 2,4-dihydroxybenzophenone 2,2′-dihydroxy-4-methoxybenzophenone, 2,2′-dihydroxy-4,4′-dimethoxybenzophenone, 2,2 ′, 4,4′-tetrahydroxybenzophenone, 2- (2-hydroxy-5 -Methylpheny ) Benzotriazole, 2- (2-hydroxy-5-t-butylphenyl) benzotriazole, 2- (2-hydroxy-3,5-dimethylphenyl) benzotriazole, 2- (2-methyl-4-hydroxyphenyl) Benzotriazole, 2- (2-hydroxy-3-methyl-5-t-butylphenyl) benzotriazole, 2- (2-hydroxy-3,5-di-t-butylphenyl) benzotriazole, 2- (2- Hydroxy-3,5-dimethylphenyl) -5-methoxybenzotriazole, 2- (2-hydroxy-3-tert-butyl-5-methylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-5- t-butylphenyl) -5-chlorobenzotriazole, 2- [4,6-bis (2,4-dimethylphenyl) -1,3,5-triazin-2-yl] -5- (octyloxy) phenol, 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5- (hexyloxy) Phenol, phenyl salicylate, p-octylphenyl salicylate and the like can be mentioned.

  The light stabilizer is used in combination with an ultraviolet absorber to impart weather resistance, and includes a hindered amine light stabilizer. The addition amount of the light stabilizer is not particularly limited, but is 0.01 to 3 weights with respect to 100 parts by weight in total of the ethylene copolymer, the layered metal compound or / and the fired product thereof, and the ketoenol tautomer. It is preferable to use parts. Specific examples include dimethyl succinate-1- (2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate, poly [{6- (1,1,3,3 -Tetramethylbutyl) amino-1,3,5-triazine-2,4-diyl} {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {{2,2,6 6-tetramethyl-4-piperidyl) imino}], N, N′-bis (3-aminopropyl) ethylenediamine-2,4-bis [N-butyl-N- (1,2,2,6,6- Pentamethyl-4-piperidyl) amino] -6-chloro-1,3,5-triazine condensate, bis (2,2,6,6-tetramethyl-4-piperidyl) separate, 2- (3,5-di -Tert-4-hydroxybenzyl)- Such -n- butyl malonic acid bis (1,2,2,6,6-pentamethyl-4-piperidyl) can be mentioned.

  Antioxidants are used to impart stability at high temperatures, and include monophenolic, bisphenolic, polymeric phenolic, sulfur-based, phosphoric acid-based and the like. The addition amount is not particularly limited, but 0.05 to 3 parts by weight is used with respect to a total of 100 parts by weight of the ethylene copolymer, the layered metal compound or / and the fired product thereof, and the ketoenol tautomer. preferable. Specific examples include 2,6-di-tert-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-tert-butyl-4-ethylphenol, 2,2′-methylene-bis- ( 4-methyl-6-tert-butylphenol), 2,2'-methylene-bis- (4-ethyl-6-tert-butylphenol), 4,4'-thiobis- (3-methyl-6-tert-butylphenol) 4,4′-butylidene-bis- (3-methyl-6-tert-butylphenol), 3,9-bis [{1,1-dimethyl-2- {β- (3-tert-butyl-4-hydroxy -5-methylphenyl) propionyloxy} ethyl} 2,4,8,10-tetraoxaspiro] 5,5-undecane, 1,1,3-tris- (2-methyl-4-hi Loxy-5-tert-butylphenyl) butane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, tetrakis- {methylene-3 -(3 ', 5'-di-tert-butyl-4'-hydroxyphenyl) propionate} methane, bis {(3,3'-bis-4'-hydroxy-3'-tert-butylphenyl) butyric Acid} glycol ester, dilauryl thiodipropionate, dimyristyl thiodipropionate, distearyl thiopropionate, triphenyl phosphite, diphenylisodecyl phosphite, phenyl diisodecyl phosphite, 4,4′-butylidene- Bis- (3-methyl-6-tert-butylphenyl-di-tridecyl) phos Phyto, cyclic neopentanetetrayl bis (octadecyl phosphite), trisdiphenyl phosphite, diisodecenorepentaerythritol diphosphite, 9,10-dihydro-9-oxa-10-phosphaphenalene-10-oxide 10- (3,5-di-tert-butyl-4-hydroxybenzyl) -9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10-decyloxy-9,10- Dihydro-9-oxa-10-phosphaphenanthrene, cyclic neopentanetetraylbis (2,4-di-tert-butylphenyl) phosphite, cyclic neopentanetetraylbis (2,6-di-) tert-methylphenyl) phosphite, 2,2-methylenebis ( , And a 6-tert-butylphenyl) octyl phosphite.

  The resin composition for a solar cell encapsulant of the present invention is obtained by mixing, melting and kneading raw materials containing a layered composite metal compound (A), a compound (C) and an ethylene copolymer (D), and forming into a pellet form. Can be manufactured. At this time, it is also possible to produce a master batch in which the layered composite metal compound (A) and the compound (C) are blended in advance higher than the concentration in the sealing material that is the final molded product. When shape | molding a sealing material using a masterbatch, it is preferable to mix | blend a masterbatch with 1-25 weight part with respect to 100 weight part of ethylene copolymers (D). When the amount is less than 1 part by weight, there is a risk of causing uneven distribution. When the amount is more than 25 parts by weight, handling properties are inferior.

Here, it is preferable to use a Henschel mixer, a super mixer, a tumbler mixer, or the like, which is a general high-speed shear mixer or rotary mixer.
The melt kneading is preferably performed using a two-roll, three-roll, pressure kneader, Banbury mixer, single-screw kneading extruder, twin-screw kneading extruder, or the like.

  By producing a resin composition for a solar cell encapsulant as a master batch, the layered composite metal compound (A) and the compound (C) are brought into contact with high probability, and fluorescence due to the wavelength conversion effect can be more easily obtained. Initial conversion efficiency can also be improved. The production of the resin composition for a solar cell encapsulant is preferably obtained, for example, by melt kneading at 70 to 160 ° C. for 1 to 20 minutes, and more preferably at 70 to 130 ° C. for 1 to 10 minutes.

  The solar cell encapsulant can be produced by melting and kneading and molding a resin composition for a solar cell encapsulant. As a molding method, a T-die extruder, a calendar molding machine, or the like can be used. The thickness of the solar cell encapsulant is preferably about 0.1 to 1 mm.

  The solar cell encapsulating material is also preferably produced by melt-kneading and extruding the resin composition for a solar cell encapsulating material obtained as a master batch and an ethylene copolymer for dilution. . A fluorescent material can be disperse | distributed more highly by manufacturing a solar cell sealing material using a masterbatch.

  In FIG. 1, an example of the structure of the solar cell module of this invention is shown. Reference numeral 11 in FIG. 1 is a transparent substrate, 12A is a front surface solar cell sealing material, 12B is a back surface solar cell sealing material, 13 is a power generation element, and 14 is a protective member. The power generating element 13 is sandwiched between the front surface solar cell sealing material 12A and the back surface solar cell sealing material 12B. The laminate is sandwiched between the transparent substrate 11 and the protective member 14. The solar cell module can be produced by fixing solar cell sealing materials on the top and bottom of the solar cell element. Generally, it is manufactured by thermocompression bonding using a vacuum laminator. Lamination conditions vary depending on the type of cross-linking agent used, but vacuum and pressure bonding are generally performed at a temperature of 130 to 150 ° C. for 10 to 30 minutes. As such a solar cell module, for example, as shown in the example of FIG. Protect solar cell encapsulant with solar cell encapsulant, such as super straight structure sandwiched by cell encapsulant or transparent substrate / solar cell element / solar cell encapsulant / protective member The thing laminated | stacked with the member is mentioned. For the transparent substrate, a heat-strengthened white plate glass or a transparent film is used, and for the sealing material, an ethylene vinyl acetate copolymer having excellent moisture resistance is used. In addition, a sheet having a structure in which aluminum is sandwiched between vinyl fluoride films, a sheet in which aluminum is sandwiched between hydrolysis-resistant polyethylene terephthalate films, and the like are used as protective members that are required to be moistureproof and insulating. Moreover, in order to raise the adhesiveness of a sealing material and a protection member, the protection member which laminated | stacked linear low density polyethylene on the upper surface, such as a hydrolysis resistant polyethylene terephthalate, is also used.

  EXAMPLES The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. “Part” means “part by weight” and “%” means “% by weight”.

(A-1 to A-7): layered composite metal compound (B-1): fired product obtained by heat-treating the layered composite metal compound (A-1) at 400 ° C. for 3 and a half hours (B-2): layered composite metal compound Baked product (B-3) obtained by heat-treating (A-2) at 650 ° C. for 4 hours: Baked product obtained by heat-treating layered composite metal compound (A-3) for 3 hours at 800 ° C. (B-4): layered composite metal compound A fired product obtained by heat-treating (A-6) at 750 ° C. for 4 hours.

The chemical compositions (B-1) to (B-4) and the BET specific surface area are shown in Table 1.

(C) Compound (C-1) 2,4′-dihydroxy-3-t-butylbenzophenone (C-2) 2,5-dihydroxy-3-t-butylbenzophenone (C-3) 2,5-dihydroxy- 3-Benzylbenzophenone (C-4) 2,4′-dihydroxy-3-tert-butyl-4-methoxybenzophenone

  Next, a production method of the above compound (C-2) using 2,4-dihydroxy-3-t-butylbenzophenone as an example will be described.

90 g of 2-t-butylphenol, 91 g of p-hydroxybenzoic acid, 105 g of zinc chloride, 170 g of phosphorus oxychloride, 120 g of sulfolene and 2 g of i-propanol are charged into a 1 liter glass four-necked flask and heated to 50 ° C. After keeping at that temperature for 2 hours, the solution was dropped into 5 liters of water. After washing with water, the product was dissolved in hot water, treated with activated carbon, cooled, recrystallized, filtered and dried, thereby obtaining 7 g of 2,4'-dihydroxy-3-t-butylbenzophenone.

(D) Ethylene copolymer (D-1) manufactured by Tosoh Corporation (Ultrasen 751, ethylene vinyl acetate copolymer, vinyl acetate content: 28%, MFR: 5.7)
(D-2) manufactured by Tosoh Corporation (Ultrasen 637-1, ethylene vinyl acetate copolymer, vinyl acetate content: 20%, MFR: 8.0)
(D-3) Mitsui-DuPont Polychemical Co., Ltd. (Evaflex V523, ethylene vinyl acetate copolymer, vinyl acetate content: 33%, MFR: 14)

Example 1
50 parts by weight of the compound (C) is previously mixed with three rolls with respect to 100 parts by weight of the layered composite metal compound, and 90% by weight of the ethylene copolymer, the layered composite metal compound, and 10% by weight of the compound are tumbler mixer. After being put into (made by Kawata) and stirred for 3 minutes at a temperature of 25 ° C., it was put into a twin screw extruder (made by Nippon Placon), melt kneaded, and extruded to obtain a phosphor master batch. In addition, 75% by weight of an ethylene copolymer, 10% by weight of a crosslinking agent, 10% by weight of a crosslinking aid, and 5% by weight of a silane coupling agent are charged into a twin screw extruder, melt kneaded, and extruded to crosslink the master. A stabilizer masterbatch was obtained in the same manner as the crosslinker masterbatch with the batch, 80% by weight of the ethylene copolymer, 5% by weight of the UV absorber, 10% by weight of the light stabilizer, and 5% by weight of the antioxidant. Further, 100 parts by weight of the obtained phosphor masterbatch and ethylene copolymer were blended so as to have the blending ratios shown in Table 2. Furthermore, 10 parts by weight of the crosslinker masterbatch and 2 parts by weight of the stabilizer masterbatch are blended with 100 parts by weight of the phosphor masterbatch and the ethylene copolymer, and these are put into a T-die extruder. The solar cell sealing materials 12A, 12B, 16, 18, and 19 (thickness 0.5 mm) were produced by extrusion molding at 90 ° C. In addition, the kind of the crosslinking agent in a solar cell sealing material, a crosslinking adjuvant, a silane coupling agent, a ultraviolet absorber, a light stabilizer, and antioxidant is used as follows.
Cross-linking agent: t-butylperoxy-2-ethylhexyl monocarbonate Cross-linking aid: triallyl isocyanurate silane coupling agent: γ-methacryloxypropyltrimethoxysilane UV absorber: 2-hydroxy-4-octoxybenzophenone light stability Agent: N, N′-bis (3-aminopropyl) ethylenediamine-2,4-bis [N-butyl-N- (1,2,2,6,6-pentamethyl-4-piperidyl) amino] -6 Chloro-1,3,5-triazine condensate antioxidant: phenyl diisodecyl phosphite

(Examples 2 to 18)
A phosphor master batch was prepared by changing the compounding ratio of the layered composite metal compound and the compound (C) so as to have the composition shown in Table 2, and the resin composition for solar cell encapsulant was prepared in the same manner as in Example 1. Were adjusted, and solar cell sealing materials 12A, 12B, 16, 18, and 19 were prepared.

(Comparative Examples 1-8)
90 parts by weight of an ethylene copolymer and 10 parts by weight of an organometallic complex shown in Table 3 were put into a tumbler mixer (manufactured by Kawata) and stirred at a temperature of 20 ° C. for 3 minutes, and then put into a twin screw extruder (manufactured by Nippon Placon). The phosphor master batch was obtained by charging, melting and kneading, and extruding. Moreover, the crosslinking agent masterbatch and the stabilizer masterbatch were obtained similarly to Example 1. The solar cell encapsulant 12A, 12B, 16, except that the obtained phosphor masterbatch, crosslinker masterbatch, stabilizer masterbatch, and further the formulation shown in Table 4 were used. 18 and 19 were created.

  The test pieces obtained in Examples 1 to 18 and Comparative Examples 1 to 8 were evaluated according to the following criteria, and the evaluation results are shown in Table 5.

[Wavelength conversion effect]
As shown in FIG. 2, the solar cell sealing materials 16 obtained in Examples 1 to 18 and Comparative Examples 1 to 8 were sandwiched between transparent substrates (glass thickness 3 mm) 15 and 17 and laminated. Then, under vacuum with a vacuum laminator, heat sealing was performed at 150 ° C. for 5 minutes and for 15 minutes to crosslink the sealing material, thereby preparing a test sample 1. The fluorescence intensity of the test sample 1 was measured with a spectrofluorometer manufactured by Hitachi High-Tech.

[Yellow]
As shown in FIG. 2, the solar cell sealing materials 16 obtained in Examples 1 to 18 and Comparative Examples 1 to 8 were sandwiched between transparent substrates (glass thickness 3 mm) 15 and 17 and laminated. Thereafter, under a vacuum with a vacuum laminator, 150 ° C., 5 minutes of heating, and 15 minutes of thermocompression bonding were performed, the sealing material was crosslinked, and a sample 1 for durability test was produced. The durability test sample 1 was accelerated by an accelerated test to promote resin yellowing due to photodegradation, and the difference in yellowness before and after the durability test was measured by a computer color matching system manufactured by KURABO. The smaller the difference in yellowness, the smaller the resin yellowing.

The acceleration test was carried out using a super UV test machine, and the durability test sample 1 was allowed to stand for 10 days in an environment of a temperature of 63 ° C., a humidity of 50% RH, and an irradiance of 100 mW / cm ² .

[Light resistance]
As shown in FIG. 2, the solar cell encapsulant 16 obtained in Examples 1 to 18 and Comparative Examples 1 to 8 was sandwiched between transparent substrates (glass thickness 3 mm) 15 and 17 and laminated. Then, under a vacuum with a vacuum laminator, 150 ° C., 5 minutes of heating, and 15 minutes of thermocompression bonding were carried out to crosslink the sealing material, thereby preparing a sample 2 for durability test. After the endurance test sample 2 was promoted to photodegradation by an accelerated test, the fluorescence intensity was measured with a fluorometer to obtain the retention rate from the initial fluorescence intensity.

The acceleration test was performed using a super UV test machine, and the sample for durability test was allowed to stand for 1, 5, 10 days in an environment of a temperature of 63 ° C., a humidity of 50% RH, and an irradiance of 100 mW / cm ² . .

[Acid capture effect]
As shown in FIG. 3 using the obtained solar cell encapsulant 18, 150 ° C. for 5 minutes and 15 minutes for thermocompression bonding under vacuum with a vacuum laminator to prepare a sample 3 for durability test, an acceleration test Then, the acid generation rate was measured by accelerating the rate of acid generation.

  In the accelerated test, 0.5 g of a sample for durability test is immersed in 30 g of purified water, and the sample is left standing for 1 hour in an environment of a temperature of 85 ° C. and a humidity of 100% RH, and then subjected to ultrasonic cleaning for 10 minutes. The amount of acetic acid contained in the water extract was quantified by ion chromatography.

[Peel strength]
As shown in FIG. 4 using the obtained solar cell encapsulating material 19, the protective member 20 of the hydrolysis-resistant polyethylene terephthalate film (thickness 0.1 mm) is made into two layers, and then under vacuum by a vacuum laminator, Durability test sample 4 was prepared by heating at 150 ° C. for 5 minutes and thermocompression bonding for 15 minutes. And the adhesiveness of the solar cell sealing material and protective member after an endurance test was measured by the peeling test.

  The endurance test was performed under the condition that the endurance test sample was left for 1000 hours in an environment of a temperature of 85 ° C. and a humidity of 85% RH.

  The peel strength between the solar cell encapsulant and the protective member was cut from a sample for durability test into a strip shape having a width of 25 mm and used as a test piece. Then, the peel strength was measured by peeling the test piece by 180 ° using a tensile tester at a tensile speed of 50 mm / min. The peel strength with time indicates the peel strength after the durability test when the peel strength of the layered composite metal compound and the sample before the durability test of Comparative Example 5 in which no compound is blended is 100.

[transparency]
As shown in FIG. 2, the solar cell sealing materials 16 obtained in Examples 1 to 18 and Comparative Examples 1 to 8 were sandwiched between transparent substrates (glass thickness 3 mm) 15 and 17 and laminated. Thereafter, under a vacuum with a vacuum laminator, 150 ° C., 5 minutes of heating, and 15 minutes of thermocompression bonding were carried out to crosslink the sealing material, and a test sample 2 was produced. The total light transmittance of the test sample 2 was measured with a haze meter manufactured by BYK-Gardner.

[Conversion efficiency]
A power generation element is sandwiched between the solar cell encapsulants 12A and 12B obtained in Examples 1 to 18 and Comparative Examples 1 to 8, and a transparent substrate (glass thickness 3 mm) 11 and a straight chain as shown in FIG. The laminate was sandwiched between 4 layers (thickness 1.0 mm) of protective members 14 of low density polyethylene resin / hydrolysis resistant polyethylene terephthalate / aluminum / hydrolysis resistant polyethylene terephthalate. Next, under vacuum by a vacuum laminator, heating was performed at 150 ° C. for 5 minutes and thermocompression bonding was performed for 15 minutes to crosslink the sealing material, thereby preparing a sample 4 for durability test. The test was performed by a super UV test under a condition of standing for 10 days in an environment of a temperature of 63 ° C., a humidity of 50% RH, and an irradiance of 100 mW / cm ² . The conversion efficiency was calculated from the incident light energy, the output at the optimum operating point, and the area of the power generation element. In the evaluation, the conversion efficiency of the power generation element alone was set to 100, and the conversion efficiency before the sample test (initial conversion efficiency) and the conversion efficiency after the test (time-dependent conversion efficiency) were obtained.

  From the results of Table 5, Examples 1 to 18 obtained excellent durability exceeding the comparative example in all evaluation items. In particular, by using a specific organic compound and a layered composite metal compound, the wavelength conversion effect lasted more than when a general organometallic complex was used, and the conversion efficiency was maintained over time. Moreover, the surprising result that the acid accompanying a resin deterioration was capture | acquired by using a layered metal compound, and the fall of adhesiveness with a protection member over time, or the fall suppression of conversion efficiency was able to be obtained was obtained.

DESCRIPTION OF SYMBOLS 11 Transparent substrate 12A Front surface solar cell sealing material 12B Back surface solar cell sealing material 13 Power generation element 14 Protection member 15 Transparent substrate 16 Sealing material 17 Transparent substrate 18 Sealing material 19 Sealing material 20 Protection member

Claims (9)

A resin composition for a solar cell encapsulant, comprising a layered composite metal compound (A), a compound (C) represented by the following general formula (1), and an ethylene copolymer (D).
General formula (1)

(In the formula, R ₁ is a halogen atom, an alkyl group having 1 to 12 carbon atoms which may have a substituent, an aryl group which may have a substituent, or an alkoxy group which may have a substituent. Or R ₂ , R ₃ , R ₆ , R ₇ , R ₈ may each independently have a hydrogen atom, a halogen atom, a hydroxy group, or a substituent. R ₄ represents an alkyl group having 1 to 12 carbon atoms, an aryl group that may have a substituent, an alkoxy group that may have a substituent, or an amino group that may have a substituent. , R ₅ and R ₉ are each independently a hydrogen atom, a halogen atom, an optionally substituted alkyl group having 1 to 12 carbon atoms, or an optionally substituted aryl group, or a substituent. An alkoxy group which may have, or an amino group which may have a substituent; It is.)   The layered composite metal compound (A) is a fired product (B) of the layered composite metal compound (A), and the resin composition for a solar cell encapsulant according to claim 1.   The resin composition for a solar cell encapsulant according to claim 2, wherein the fired product (B) is a fired product obtained by heat-treating the layered composite metal compound (A) at 150 to 850 ° C.   A layered composite metal compound (A) is hydrotalcite, The resin composition for solar cell sealing materials in any one of Claims 1-3 characterized by the above-mentioned. The layered composite metal compound (A) is a compound represented by the following general formula (2) or general formula (3), the resin composition for a solar cell encapsulant according to any one of claims 1 to 4 object.
Mg _1-a · Al _a (OH) ₂ · An ^n- _{a / n} · cH ₂ O General formula (2)
(Wherein 0.2 ≦ a ≦ 0.35, 0 ≦ c ≦ 1, An: n-valent anion)
_{(M d Mg 1-d)} 1-e · Al e (OH) 2 · An n- e / n · fH 2 O Formula (3)
(In the formula, M represents a metal selected from Ni, Zn, Cu, and Ca, and d, e, and f are the formulas 0 ≦ d ≦ 1, 0.2 ≦ e ≦ 0.35, and 0 ≦ f ≦ 1, respectively. An: n-valent anion)   The solar cell sealing material formed by using the resin composition for solar cell sealing materials in any one of Claims 1-5 at least.   3 to 15 parts by weight of the layered composite metal compound (A) and 1 to 10 parts by weight of the compound (C) represented by the general formula (1) with respect to 100 parts by weight of the ethylene copolymer (D). A masterbatch for solar cell encapsulating material.   The solar cell sealing material formed using an ethylene vinyl acetate copolymer and the masterbatch for solar cell sealing materials of Claim 7.   The solar cell module provided with the solar cell sealing material of Claim 6 or 8 at least.

Images