WO2017175524A1

WO2017175524A1 - Ion scavenger for solar cell, solar cell sealant composition containing same, and solar cell module

Info

Publication number: WO2017175524A1
Application number: PCT/JP2017/008215
Authority: WO
Inventors: 大野　康晴
Original assignee: 東亞合成株式会社
Priority date: 2016-04-05
Filing date: 2017-03-02
Publication date: 2017-10-12
Also published as: TW201808796A; TWI731941B; JPWO2017175524A1; CN108778991A; KR20180132709A; CN108778991B; JP6658871B2; KR102311985B1

Abstract

The ion scavenger for a solar cell according to the present invention contains (A) an α-zirconium phosphate in which at least a portion of ion-exchange groups is substituted by at least one type of an ion (a1) selected from among a lithium ion, a potassium ion, a cesium ion, a rubidium ion, a magnesium ion, and a calcium ion, and/or (B) an α-titanium phosphate in which at least a portion of ion-exchange groups is substituted by at least one type of an ion (b1) selected from among a lithium ion, a potassium ion, a cesium ion, a rubidium ion, a magnesium ion, and a calcium ion.

Description

Ion scavenger for solar cell, encapsulant composition for solar cell containing the same, and solar cell module

INDUSTRIAL APPLICABILITY The present invention provides a solar cell ion-trapping agent that highly selectively adsorbs Na ⁺ ions causing PID (Potential Induced Degradation) of a solar cell and provides a solar cell with excellent PID resistance, and a solar cell including the same. The present invention relates to a sealing agent composition and a solar cell module.

太陽 Solar cells are being used as a clean energy source due to increased awareness of environmental issues. Generally, a solar cell is a composite body including a plurality of solar cell modules, and the solar cell module includes a front surface side transparent protective member, a layer in which the solar cell elements are sealed, and a back surface side protective member (back sheet). It has a structure provided with.

In recent years, a large-scale solar power generation system called a mega solar that installs a large number of crystalline silicon solar cell modules on a large site and constructs a solar power generation system for electric power business has been rapidly increasing. In such a large-scale photovoltaic power generation system, in order to simplify wiring work between solar cell modules and reduce costs by reducing the number of wires and connection boxes, a large number of solar cell modules are connected in series, and the maximum system voltage is increased. It is often designed as high as 600V to 1000V. However, in such a crystalline silicon solar power generation system having a high system voltage, a sudden characteristic deterioration phenomenon called PID may occur in the crystalline silicon solar cell module.
Regarding the PID phenomenon of such a crystalline silicon solar cell module, the cause and generation mechanism have not yet been elucidated. However, the PID phenomenon is likely to occur and proceed when a high system voltage is applied to the solar cell module and the solar cell module is in a high temperature or high humidity state, and a reverse high voltage is applied to the solar cell module. It is reported that the characteristics are recovered by the above.

Hereinafter, a mechanism in which the PID phenomenon occurs in a crystalline silicon solar battery module using a crystalline silicon solar battery cell configured using a general P-type wafer will be described. The surface of the crystalline silicon solar cell module is usually covered with a cover glass made of soda lime glass. Here, when there is moisture on the surface of the cover glass, sodium ions (Na ⁺ ions) that are metal ions are generated from the soda lime glass. The cover glass of the crystalline silicon solar cell module is supported by a metal frame, and the metal frame is connected to the ground and has a ground potential.

When a negative system voltage is applied to the internal wiring of the crystalline silicon solar cell module in such a state, a large potential difference is generated inside and outside the crystalline silicon solar cell module. Na ⁺ ions (metal ions) on the surface of the cover glass move in the cover glass and in the sealing filling resin due to this potential difference, and reach the surface of the crystalline silicon solar cell. Under high temperature and high humidity conditions, the volume resistance of the cover glass and the sealing resin is reduced, the leakage current is increased, and Na ⁺ ions (metal ions) are easily moved.

Usually, the surface of the doped layer (N-type) on the light incident side of the crystalline silicon solar battery cell is covered with an insulating passivation film. This passivation film is polarized by the attachment of charged ions. As a result, a polarity reversal region (P type) is formed in the vicinity of the interface between the doped layer (N type) of the light incident side of the crystalline silicon solar cell and the passivation layer, the movement of photogenerated carriers is prevented, and the cell characteristics are improved. descend.

As a method for preventing the occurrence of such a PID phenomenon, several methods have been proposed so far. For example, as a method for dealing with solar power generation systems, use an inverter with an insulation transformer and ground the negative electrode of the inverter input so that the inside of the solar cell module does not become negative with respect to the outside. It has been known. However, in recent years, transformer-less has been progressing for higher efficiency and cost reduction of inverters, and it is becoming difficult to cope with such systems.

On the other hand, as a method for dealing with solar cell modules, Patent Document 1 discloses an EVA in which solar cells are sealed using EVA in order to prevent water vapor from entering the solar cell module. A structure is disclosed in which an ionomer resin layer is provided on the opposite side of a resin solar battery cell.
Further, although the improvement of the PID phenomenon is not directly aimed at, the study has been made to increase the volume resistivity of the sealing material. In Patent Document 2, a silane coupling agent having 4 or less carbon atoms in a functional group directly bonded to a silicon atom is added at a ratio of 5 parts by weight or less with respect to 100 parts by weight of an ethylene / vinyl acetate copolymer. A solar cell encapsulant is disclosed. Patent Document 3 includes a structural unit derived from ethylene and a structural unit derived from an unsaturated ester, and the total of the structural unit derived from ethylene and the structural unit derived from an unsaturated ester is 100 mass. %, A resin containing 0.001 to 5 parts by mass of metakaolin with respect to 100 parts by mass of the ethylene-unsaturated ester copolymer whose amount of structural units derived from the unsaturated ester is 20 to 35% by mass. A solar cell encapsulant obtained using the composition is disclosed.
Further, Patent Document 4 discloses an inorganic ion collection selected from the group consisting of ethylene copolymers, pentavalent metal oxides, hexavalent metal oxides, heptavalent metal oxides, and phosphate metal salts. The resin composition for solar cell sealing materials containing an agent is disclosed.

JP 2011-77172 A Japanese Patent Laid-Open No. 11-54766 JP2013-64115A JP2015-138805A

Patent Document 4 describes an example using zirconium phosphate (an inorganic ion exchanger) as a metal phosphate, but this ion scavenger captures Na ⁺ ions, but is not sufficient. In addition, since H ⁺ ions are released by ion exchange, depending on the configuration, there is a problem in that the pH is lowered and the sealing resin is adversely affected, or corrosion of the constituent members of the solar cell element such as electrodes is promoted. .
An object of the present invention is to provide an ion scavenger for solar cell that highly selectively adsorbs Na ⁺ ions that cause PID of the solar cell.
Another object of the present invention is to provide a solar cell encapsulant composition that suppresses the decrease in output caused by PID and the corrosion of constituent members of solar cell elements such as electrodes, and a long-life solar cell. Is to provide modules.

The present inventor has disclosed that α-zirconium phosphate in which at least a part of an ion exchange group is substituted with at least one ion selected from lithium ion, potassium ion, rubidium ion, cesium ion, magnesium ion and calcium ion, and , At least part of the ion exchange group contains at least one of α-titanium phosphate substituted with at least one ion selected from lithium ion, potassium ion, cesium ion, rubidium ion, magnesium ion and calcium ion It was found that the ion scavenger for solar cells selectively adsorbs Na ⁺ ions resulting from PID, and the present invention was completed.
1. (A) α-zirconium phosphate in which at least part of the ion exchange group is substituted with at least one ion (a1) selected from lithium ion, potassium ion, cesium ion, rubidium ion, magnesium ion and calcium ion; (B) α-phosphoric acid in which at least a part of the ion exchange group is substituted with at least one ion (b1) selected from lithium ion, potassium ion, cesium ion, rubidium ion, magnesium ion and calcium ion An ion scavenger for solar cells, comprising at least one of titanium.
2. 2. The ion trap for solar cell according to 1 above, wherein the component (A) is α-zirconium phosphate in which 0.1 to 6.7 meq / g of the total ion exchange capacity is substituted with the ion (a1) Agent.
3. 3. The ion scavenger for solar cells according to 1 or 2 above, wherein the α-zirconium phosphate before being substituted with the ion (a1) is a compound represented by the following formula (1).
_{_{_{_{Zr 1-x Hf x H a}}}} (PO 4) b · mH 2 O (1)
(Where 0 ≦ x ≦ 0.2, 2 <b ≦ 2.1, a is a positive number satisfying 3b−a = 4, and 0 ≦ m ≦ 2.)
4). The component (B) is the α-titanium phosphate in which 0.1 to 7.0 meq / g of the total ion exchange capacity is substituted with the ion (b1). The ion-trapping agent for solar cells as described.
5. The ion scavenger for solar cells according to any one of 1 to 4 above, wherein the α-titanium phosphate before being substituted with the ion (b1) is a compound represented by the following formula (2).
TiH _s (PO ₄ ) _t · nH ₂ O (2)
(In the formula, 2 <t ≦ 2.1, s is a positive number satisfying 3t−s = 4, and 0 ≦ n ≦ 2.)
6). A solar cell encapsulant composition comprising: the solar cell ion scavenger according to any one of 1 to 5 above; and a resin.
7). 7. The solar cell encapsulant composition as described in 6 above, wherein the resin contains an ethylene / vinyl acetate copolymer resin.
8). The solar cell element for solar cells according to 6 or 7 above, between the front surface side transparent protective member, the back surface side protective member, the solar cell element, and the front surface side transparent protective member and the back surface side protective member. A solar cell module comprising: a sealing layer sealed with a sealant composition.

The ion scavenger for solar cells of the present invention adsorbs Na ⁺ ions that cause PID of solar cells with high selectivity and does not easily release H ⁺ ions. Therefore, a decrease in output due to PID is suppressed. Moreover, the sealing agent composition for solar cells of this invention can suppress the corrosion of the structural member of solar cell elements, such as an electrode, and can provide a long-life solar cell module.

It is a schematic sectional drawing which shows the solar cell module of this invention.

Hereinafter, the present invention will be described in detail.
1. Ion scavenger for solar cell The ion scavenger for solar cell of the present invention is (A) at least part of the ion exchange group is selected from lithium ion, potassium ion, cesium ion, rubidium ion, magnesium ion and calcium ion. Α-zirconium phosphate substituted with one kind of ion (a1) (hereinafter referred to as “ion trapping agent for solar cell (A)”), and (B) at least part of the ion exchange group is lithium ion, potassium Α-titanium phosphate substituted with at least one ion (b1) selected from ions, cesium ions, rubidium ions, magnesium ions and calcium ions (hereinafter referred to as “ion trapping agent for solar cells (B)”) At least one of the above. The ion exchange group is usually a proton.
In the present invention, the solar cell ion-trapping agent is, for example, a solar cell element 11 constituting the solar cell module 10 shown in FIG. Inclusion in at least one of the sealing layer 13 containing the resin and the back surface side protection member 17 out of the protection member 15 and the back surface side protection member 17 can increase the life of the solar cell. That is, since the ion scavenger for solar cells of the present invention does not release protons (H ⁺ ), it is suppressed that the constituent members of the solar cell are decomposed or deteriorated, and a decrease in output is also suppressed. The

Since both α-zirconium phosphate before substitution with the ion (a1) and α-titanium phosphate before substitution with the ion (b1) have many OH groups in the layer, By adopting a structure in which lithium ions, potassium ions, rubidium ions, cesium ions, magnesium ions or calcium ions are substituted in advance, it is considered that Na ⁺ ions are selectively adsorbed without releasing H ⁺ ions. It is done.
Since the ion scavenger for solar cells of the present invention is neutral, even when it is added to the electrolytic solution, its pH does not fluctuate greatly. When the sealing layer 13 contains an alkaline or acidic substance, the resin may be decomposed with a change in pH. For example, when the resin includes an ethylene / vinyl acetate copolymer resin, acetic acid and the like are easily generated, leading to deterioration of the solar cell. However, if the sealing layer includes the solar cell ion scavenger of the present invention, Such a problem does not occur.
Moreover, since the ion scavenger for solar cells of the present invention is an inorganic compound, it is excellent in thermal stability and stability in a solvent. For this reason, when it is made to contain in the structural member of a solar cell, it is stable even in the state where the electric charge was applied.

1-1. Ion scavenger for solar cells (A)
As described above, the ion scavenger (A) for solar cells of the present invention is a substitution product of α-zirconium phosphate ions (a1).
The α-zirconium phosphate is a compound represented by the following formula (1).
_{_{_{_{Zr 1-x Hf x H a}}}} (PO 4) b · mH 2 O (1)
(In the formula, 0 ≦ x ≦ 0.2, 2 <b ≦ 2.1, a is a number satisfying 3b−a = 4, and 0 ≦ m ≦ 2.)

Since the ion exchange group of the α-zirconium phosphate is usually a proton, a part or all of the proton is substituted with the ion (a1) to form the ion trapping agent (A) for solar cell of the present invention. Is done. The ion (a1) is at least one selected from lithium ion, potassium ion, cesium ion, rubidium ion, magnesium ion, and calcium ion, but from the viewpoint of good capturing properties of Na ⁺ ions, An ion derived from an alkali metal element (lithium ion, potassium ion, rubidium ion or cesium ion) is preferable.
In the ion scavenger (A) for solar cells of the present invention, the amount of the substituted ion (a1) is preferably 0.1 to 6.7 meq / g, more preferably 1.0 to 6.7 meq / g. It is. From the viewpoint of Na ⁺ ion adsorption ability, 3.5 to 6.7 meq / g is more preferable.

In the above formula (1), x is preferably 0 ≦ x ≦ 0.1, more preferably 0 ≦ x ≦ 0.02, from the viewpoint of Na ⁺ ion trapping properties. When Hf is contained, it is preferably 0.005 ≦ x ≦ 0.1, more preferably 0.005 ≦ x ≦ 0.02. In the case of x> 0.2, the ion exchange performance by the ions (a1) is improved, but since radioactive isotopes are present, when the components of the solar cell include electronic components, it may have an adverse effect.

The method for producing the ion scavenger (A) for solar cells of the present invention is not particularly limited. For example, when producing α-zirconium phosphate substituted with lithium ions, α-zirconium phosphate is added to a lithium hydroxide (LiOH) aqueous solution, stirred for a certain period of time, filtered, washed and dried. be able to. The concentration of the LiOH aqueous solution is not particularly limited. In the case of a high concentration, the basicity of the reaction solution becomes high, and a part of α-zirconium phosphate may be eluted, so that it is preferably 1 mol / L or less, more preferably 0.1 mol / L or less.
When producing α-zirconium phosphate substituted with potassium ions, the same ion exchange method as described above can be applied.

When α-zirconium phosphate substituted with magnesium ion or calcium ion is produced, magnesium or calcium hydroxide is difficult to dissolve in water. Substitution can be made using an aqueous solution of magnesium or the like. Further, for example, the same operation may be performed by adding α-zirconium phosphate to a magnesium acetate aqueous solution.

1-2. Ion scavenger for solar cells (B)
As described above, the solar cell ion scavenger (B) of the present invention is a substitution product of α-titanium phosphate ions (b1).
The α-titanium phosphate is a compound represented by the following formula (2).
TiH _s (PO ₄ ) _t · nH ₂ O (2)
(In the formula, 2 <t ≦ 2.1, s is a number satisfying 3t−s = 4, and 0 ≦ n ≦ 2.)

Since the ion-exchange group of α-titanium phosphate is usually a proton, a part or all of this proton is substituted with the ion (b1) to form the ion-trapping agent (B) for solar cells of the present invention. The The ion (b1) is at least one selected from lithium ion, potassium ion, cesium ion, rubidium ion, magnesium ion, and calcium ion, but from the viewpoint of good capturing properties of Na ⁺ ions, An ion derived from an alkali metal element (lithium ion, potassium ion, rubidium ion or cesium ion) is preferable.
In the ion scavenger (B) for solar cells of the present invention, the amount of the substituted ion (b1) is preferably 0.1 to 7.0 meq / g, more preferably 1.0 to 7.0 meq / g. It is. From the viewpoint of Na ⁺ ion adsorption capacity, 3.5 to 7.0 meq / g is more preferable.

The method for producing the ion scavenger for solar cells (B) of the present invention is not particularly limited, and can be the same method as the method for producing the ion scavenger for solar cells (A).

The ion scavenger for solar cells of the present invention usually has a layered structure, and the upper limit of the median particle size is preferably 5.0 μm, more preferably 3.0 μm, still more preferably 2.0 μm, and the lower limit is The thickness is usually 0.2 μm, preferably 0.5 μm. What is necessary is just to select a preferable particle size by the kind of structural member to which the ion scavenger for solar cells of this invention is applied.

The water content of the ion scavenger for solar cells of the present invention is preferably 10% by mass or less, more preferably 5% by mass or less. When the moisture content is 10% by mass or less, in the case of a member constituting a solar cell, it is possible to suppress the generation of gas due to the occurrence of water electrolysis, and to suppress the malfunction of the battery. be able to. The water content can be measured by the Karl Fischer method.

When the moisture content of the ion scavenger for solar cells is 10% by mass or less, there is no particular limitation, and a commonly used powder drying method can be applied. For example, a method of heating at 100 ° C. to 300 ° C. for about 6 to 24 hours under atmospheric pressure or reduced pressure can be mentioned.

2. Solar Cell Sealant Composition The solar cell sealant composition of the present invention contains the above-described solar cell ion scavenger of the present invention and a resin. The solar cell encapsulant composition of the present invention may contain other components such as a crosslinking agent, a crosslinking aid, an adhesion improver, an ultraviolet absorber, a light stabilizer, and an antioxidant, which will be described later. it can.
The sealing composition for solar cells of the present invention is suitable for forming the sealing layer 13 between the front surface side transparent protective member 15 and the back surface side protective member 17 constituting the solar cell module 10 shown in FIG. It is.

Examples of the resin contained in the solar cell encapsulant composition of the present invention include ethylene / vinyl acetate copolymer resins; polyolefin resins such as polyethylene and polypropylene; ionomer resins; ethylene / methacrylic acid copolymers; ethylene / methacrylic acid. Examples include ester copolymers; ethylene / acrylic acid copolymers; ethylene / acrylic acid ester copolymers; polyvinyl fluoride resins; polyvinyl chloride resins. Among these, an ethylene / vinyl acetate copolymer resin is particularly preferable because a sealing layer having excellent transparency can be formed.

The ethylene / vinyl acetate copolymer resin is not particularly limited, but has a heat resistance of 100 ° C. to 150 ° C. due to a high degree of cross-linking due to a high gel fraction after, for example, a vacuum heating lamination process when manufacturing a solar cell module. Since it can be obtained smoothly, an ethylene / vinyl acetate copolymer in which the content of structural units derived from vinyl acetate is preferably 20 to 40% by mass, more preferably 25 to 35% by mass, still more preferably 28 to 33% by mass. Polymerized resins are preferred.
The melt mass flow rate (MFR) of the ethylene / vinyl acetate copolymer resin is preferably 1 g to 40 g / 10 min, more preferably 15 g to 40 g / 10 min in a method (190 ° C.) according to JIS K 7210. The Vicat softening point is preferably 30 ° C. to 40 ° C. in a method according to JIS K 7206.

In the encapsulant composition for solar cells of the present invention, the content ratio of the ion scavenger for solar cells is the content of the resin from the viewpoint of the transparency of the encapsulating layer and the ability to capture Na ⁺ ions in the encapsulating layer. Is preferably 0.01 to 1.0 part by mass, more preferably 0.05 to 0.5 part by mass. The median particle size of the ion scavenger for solar cells is preferably 0.5 to 5.0 μm, more preferably 0.7 to 2.0 μm, from the viewpoint of power generation efficiency of the solar cell.

The sealing agent composition for solar cells of the present invention may contain other components as described above.
As the crosslinking agent, an organic peroxide, an azo compound, a tin compound, or the like can be used. These may be used alone or in combination of two or more.
Examples of organic peroxides include hydroperoxides such as diisopropylbenzene hydroperoxide and 2,5-dimethyl-2,5-di (hydroperoxy) hexane; di-tert-butyl peroxide, tert-butyl cumylper Dialkyl peroxides such as oxide, dicumyl peroxide, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane, 2,5-dimethyl-2,5-di (tert-peroxy) hexyne-3 Oxides; diacyl peroxides such as bis-3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, benzoyl peroxide, o-methylbenzoyl peroxide, 2,4-dichlorobenzoyl peroxide; tert- Butyl peroxyacete Tert-butyl peroxy-2-ethylhexanoate, tert-butyl peroxypivalate, tert-butyl peroxy octoate, tert-butyl peroxyisopropyl carbonate, tert-butyl peroxybenzoate, di-tert- Butyl peroxyphthalate, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, 2,5-dimethyl-2,5-di (benzoylperoxy) hexyne-3, tert-butylperoxy-2 -Peroxyesters such as ethyl hexyl carbonate; ketone peroxides such as methyl ethyl ketone peroxide and cyclohexanone peroxide.
Examples of the azo compound include azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile).
Examples of the tin compound include dibutyltin diacetate, dibutyltin dilaurate, dibutyltin dioctate, and dioctyltin dilaurate.

When the encapsulant composition for solar cells of the present invention contains a crosslinking agent, the content ratio is preferably 0.01 to 2.0 parts by mass when the content of the resin is 100 parts by mass, More preferably, it is 0.05 to 1.5 parts by mass.

The crosslinking aid promotes a crosslinking reaction by the crosslinking agent, and is preferably a polyfunctional monomer having at least one of a carbon atom-carbon atom double bond and an epoxy group, more preferably an allyl group, methacryloyl. Group, an acryloyl group, a vinyl group and the like, and specific examples include polyallyl compounds, poly (meth) acryloxy compounds, and epoxy compounds. These may be used alone or in combination of two or more.
Examples of the polyallyl compound include triallyl isocyanurate, triallyl cyanurate, diallyl phthalate, diallyl fumarate, diallyl maleate and the like.
Examples of the poly (meth) acryloxy compound include trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1 , 9-nonanediol diacrylate and the like.
Epoxy compounds include glycidyl acrylate, glycidyl methacrylate, 4-hydroxybutyl acrylate glycidyl ether, 1,6-hexanediol diglycidyl ether, 1,4-butanediol diglycidyl ether, cyclohexanedimethanol diglycidyl ether, trimethylol. Examples include propane polyglycidyl ether.

When the encapsulant composition for solar cells of the present invention contains a crosslinking aid, the content is preferably 0.01 to 3.0 parts by mass when the content of the resin is 100 parts by mass. More preferably, it is 0.05 to 2.0 parts by mass.

The adhesion improver is preferably a silane compound having a polymerizable unsaturated bond such as a methacryloyl group, an acryloyl group, or a vinyl group, or a hydrolyzable group such as an alkoxy group. A coupling agent can be used.
Examples of the silane coupling agent include vinyltrichlorosilane, vinyltris (β-methoxyethoxy) silane, vinyltriethoxysilane, vinyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl). Ethyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, γ-aminopropyl Examples include triethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, and γ-chloropropyltrimethoxysilane.

When the sealing agent composition for solar cells of the present invention contains an adhesion improver, the content is preferably 0.01 to 3.0 mass when the content of the resin is 100 mass parts. Part.

Examples of the ultraviolet absorber include benzophenone compounds, benzotriazole compounds, triazine compounds, salicylic acid ester compounds, and the like. These may be used alone or in combination of two or more.
Examples of the ultraviolet absorber include 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-2'-carboxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-n-dodecyloxy Benzophenone, 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-me Ruphenyl) benzotriazole, 2- (2-hydroxy-5-tert-butylphenyl) benzotriazole, 2- (2-hydroxy-3,5-dimethylphenyl) benzotriazole, 2- (2-methyl-4-hydroxyphenyl) ) Benzotriazole, 2- (2-hydroxy-3-methyl-5-tert-butylphenyl) benzotriazole, 2- (2-hydroxy-3,5-di-tert-butylphenyl) benzotriazole, 2- (2 -Hydroxy-3,5-dimethylphenyl) -5-methoxybenzotriazole, 2- (2-hydroxy-3-tert-butyl-5-methylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-5 -Tert-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- And triazin-2-yl) -5- (hexyloxy) phenol, phenyl salicylate, p-octylphenyl salicylate, and the like.

When the encapsulant composition for solar cells of the present invention contains an ultraviolet absorber, the content is preferably 0.01 to 3.0 parts by mass when the content of the resin is 100 parts by mass. It is.

The light stabilizer is not particularly limited as long as it captures radicals generated by photodegradation, and a hindered amine compound, a thiol compound, a thioether compound, or the like can be used. These may be used alone or in combination of two or more.
The light stabilizer is preferably a hindered amine compound, and specific examples thereof include dimethyl-1- (2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate of succinate. , 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) seba Over DOO, 2- (3,5-di-tert.-4-hydroxybenzyl) -2-n-butyl malonic acid bis (1,2,2,6,6-pentamethyl-4-piperidyl) and the like.

When the encapsulant composition for solar cells of the present invention contains a light stabilizer, the content is preferably 0.01 to 3.0 parts by mass when the content of the resin is 100 parts by mass. It is.

The antioxidant is not particularly limited as long as it provides thermal stability against the heat energy of sunlight. Monophenol compound, bisphenol compound, polymer phenol compound, sulfur compound, phosphoric acid compound Etc. can be used. These may be used alone or in combination of two or more.
Examples of the antioxidant 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-hydroxy-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, diphenyl isodecyl phosphite, phenyl diisodecyl phosphite, 4,4'- Butylidene-bis- (3-methyl-6-tert-butylphenyl-di-tridec Phosphite, 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-methyle Bis (4, 6-tert-butylphenyl) octyl phosphite, and the like.

When the encapsulant composition for solar cells of the present invention contains an antioxidant, the content ratio is preferably 0.05 to 3.0 parts by mass when the content of the resin is 100 parts by mass. It is.

The encapsulant composition for solar cells of the present invention can be produced by mixing raw material components, but the ion-trapping agent for solar cells, other components, etc. are used as a matrix for the resin. It is preferable that it is a form disperse | distributing in. In particular, when a component that forms a crosslinked structure with a resin, such as a crosslinking agent, is blended, it is preferable that the resin be included in an uncrosslinked or semicrosslinked state.
Therefore, when forming the sealing layer 13 in FIG. 1, for example, after kneading the solar cell sealing agent composition of the present invention, it is put into an extruder and thinned by T-die molding or calendar molding. It is preferable to use an uncrosslinked or semi-crosslinked solar cell module encapsulant sheet obtained by processing into a predetermined size.

3. Solar Cell Module As shown in FIG. 1, for example, the solar cell module of the present invention includes a solar cell element 11, a front surface side transparent protective member 15, a back surface side protective member 17, and the front surface side transparent protective member 15 and Between the said back surface side protection member 17, the solar cell element 11 is provided with the sealing layer 13 sealed (embedded) using the sealing compound composition for solar cells of the said invention. The solar cell elements 11 are connected by an interconnector 19. In FIG. 1, the collecting electrode and the like are omitted.

The solar cell element 11 has a function of converting light incident on the light-receiving surface by photoelectric effect into electricity, and preferably includes silicon, a compound semiconductor, and the like.
The sealing layer 13 is preferably a layer made of a crosslinked resin composition formed using a solar cell sealing agent composition containing a crosslinking agent, and the solar cell element 11 and the interconnector 19 are predetermined. It is embedded so as to be fixed at the position.
The surface-side transparent protective member 15 is usually made of a material excellent in weather resistance, wind pressure resistance, weather resistance and the like, and can be made of a resin such as a polyester resin or a polycarbonate resin, or glass. It consists of glass such as lime glass.
The back-side protection member 17 is usually made of a material having excellent weather resistance, such as hydrolysis-resistant polyethylene terephthalate resin or polyvinyl fluoride resin. The back surface side protection member 17 may have an action of reflecting light transmitted through the sealing layer 13.

The method for producing the solar cell module of the present invention is not particularly limited, and conventionally known methods can be applied. For example, a non-crosslinked or semi-crosslinked solar cell module encapsulant sheet, a solar cell element, and a crosslink obtained by using a back surface side protective member and a solar cell encapsulant composition containing a crosslinking agent A laminate obtained by laminating an uncrosslinked or semi-crosslinked solar cell module encapsulant sheet and a surface-side transparent protective member in this order, obtained by using a solar cell encapsulant composition containing an agent. After that, the laminate can be subjected to a vacuum heating lamination method in which heat and pressure bonding is performed in a vacuum state. By this vacuum heating lamination, the solar cell element is buried between the two solar cell module encapsulant sheets to form a crosslinked resin composition, and a sealing layer and a back surface side protective member including the same, and The surface-side transparent protective member and the sealing layer can be bonded and integrated, respectively, to produce the solar cell module of the present invention.

In the solar cell module of the present invention, since the sealing layer 13 contains a special ion scavenger, moisture that has entered the sealing layer 13 and acid generated by hydrolysis are captured during use of the solar cell. In addition, the solar cell element 11 can be prevented from degrading, and when the surface-side transparent protective member is made of glass, PID (Potential-induced degradation; solar cell) is applied to the sealing layer 13 from the glass. Even if sodium ions (Na ⁺ ions), which is the main cause of the high voltage applied to the module and the output is permeated, can be prevented from diffusing, the output of the solar cell module 10 can be reduced. Can be suppressed.

Hereinafter, the present invention will be specifically described with reference to examples. However, the present invention is not limited to the following examples.

1. Evaluation method (1) pH measurement The pH of the aqueous solution after adding the ion scavenger in (2) below or the extracted water obtained in (3) below is a glass electrode type hydrogen ion concentration indicator “Horiba Ltd.” D-51 "(model name). The measurement is based on JIS Z 8802 “pH measurement method”, and the measurement temperature is 25 ° C.

(2) the Na ⁺ ion adsorption capacity of Na ⁺ ion adsorption capacity solar cell ion scavenger of ion scavenger for solar cells in the aqueous solution of NaCl, were assessed by ICP emission spectroscopy. The specific evaluation method is as follows.
First, 0.254 g NaCl was dissolved in 1 L of water to prepare an aqueous solution containing 100 ppm of Na ⁺ ions. The ion scavenger was added to the aqueous solution so as to have a concentration of 1.0% by mass, sufficiently mixed, and then allowed to stand. Then, the Na ⁺ ion concentration 8 hours after adding the ion scavenger was measured with an ICP emission spectrometer “iCAP7600 DUO” (model name) manufactured by Thermo Fisher Scientific. And Na ⁺ ion capture | acquisition rate was calculated | required by the following formula.
Na ⁺ ion capture rate = ((initial concentration (100 ppm) −Na ⁺ ion concentration after test (after 8 hours)) / initial concentration (100 ppm)) × 100

(3) Na ⁺ ion adsorption capacity of the crosslinked resin test piece formed using the sealing agent composition for solar cells, 1.0 part by mass of the ion scavenger for solar cells, and ethylene / vinyl acetate manufactured by Mitsui DuPont Polychemical Co., Ltd. 100 parts by mass of copolymer resin “EV150R” (trade name), 0.5 parts by mass of tert-butylperoxy-2-ethylhexyl carbonate “Lupelox TBEC” (trade name, cross-linking agent) manufactured by Arkema Yoshitomi, and Arkema Yoshitomi 0.5 parts by mass of 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane “Lupelox 101” (trade name, cross-linking agent) manufactured by Sartomer and trimethylolpropane trimethacrylate “SR350” 1.0 part by mass of product name, crosslinking aid) and triallyl isocyanurate “SR533” (product of Sartomer) , Crosslinking aid) 1.0 parts by mass and 0.025 parts by mass of sodium chloride manufactured by Kishida Chemical Co., Ltd. were obtained to obtain a solar cell sealant composition, and then an injection molding machine manufactured by Meiki Seisakusho Co., Ltd. Using “M-50A (II) -DM” (model name) and a molding temperature of 150 ° C., a crosslinked resin test piece (110 mm × 110 mm × 2 mm) was obtained. The sodium chloride was made to have an amount of sodium of about 100 ppm relative to the ethylene / vinyl acetate copolymer resin in order to make the difference in the measured value of Na ⁺ ion concentration between the examples and the comparative examples remarkable. Is.
Next, 10 g of this cross-linked resin test piece was cut into small pieces (about 5 mm × 5 mm × 2 mm), put into a 100 mL plastic container together with 50 mL of pure water, and sealed. And this poly container was left still at 95 degreeC for 20 hours. And the analysis and pH measurement of the extraction water containing the component eluted in the pure water from the crosslinked resin test piece were performed. Na ⁺ ion concentration was measured by ICP emission spectroscopic analysis. The acetic acid concentration was measured by ion chromatography.

2. Production and evaluation of ion scavenger Example 1
After dissolving 0.272 mol of zirconium oxychloride octahydrate in 850 mL of pure water, 0.788 mol of oxalic acid dihydrate was added and dissolved. While stirring this aqueous solution, 0.57 mol of phosphoric acid was added. This was refluxed at 103 ° C. for 8 hours while stirring. After cooling, the resulting precipitate was washed well with water, and then dried at 150 ° C. to obtain a scaly powder composed of zirconium phosphate. As a result of analyzing this zirconium phosphate, it was confirmed that it was α-zirconium phosphate (H type) (hereinafter referred to as “α-zirconium phosphate (Z1)”).
The above α-zirconium phosphate (Z1) was boiled and dissolved in nitric acid to which hydrofluoric acid was added, and then subjected to ICP emission spectroscopic analysis to obtain the following composition formula.
ZrH _2.03 (PO ₄ ) _2.01 · 0.05H ₂ O
Further, the median diameter of α-zirconium phosphate (Z1) was measured by a laser diffraction particle size distribution analyzer “LA-700” (model name) manufactured by Horiba, Ltd. As a result, it was 0.9 μm.

Next, 25 g of α-zirconium phosphate (Z1) was added while stirring 1000 mL of a 0.1N-LiOH aqueous solution, and this was stirred for 8 hours. Thereafter, the precipitate was washed with water and vacuum-dried at 150 ° C. for 20 hours to obtain lithium ion-substituted α-zirconium phosphate composed of ZrLi _1.03 H _1.00 (PO ₄ ) _2.01 · 0.05H ₂ O. Manufactured. The water content by the Karl Fischer method was 0.5%. This lithium ion-substituted α-zirconium phosphate is one in which 4 meq / g of all cation exchange capacities is replaced with lithium ions. Hereinafter, it was referred to as “4 meq-Li substituted α-zirconium phosphate A1-1”.
Next, various evaluations described above were performed using the ion scavenger for solar cells composed of this 4 meq-Li substituted α-zirconium phosphate A1-1, and the results are shown in Table 1.

Example 2
Except that the amount of 0.1N-LiOH aqueous solution used was 2500 mL, the same operation as in Example 1 was performed, and all the cation exchange groups (cation exchange capacity: 6.7 meq / g) were replaced with lithium ions. In addition, lithium ion-substituted α-zirconium phosphate composed of ZrLi _2.03 (PO ₄ ) _2.01 · 0.05H ₂ O was produced. The moisture content was 0.3%. Hereinafter, it was referred to as “all Li-substituted α-zirconium phosphate A1-2”.
Next, using the solar cell ion scavenger composed of all Li-substituted α-zirconium phosphate A1-2, the above-described various evaluations were performed, and the results are shown in Table 1.

Example 3
ZrK _1.03 H _1.00 (PO ₄ ) _2.01 · 0.0. Was carried out in the same manner as in Example 1 except that a 0.1N—KOH aqueous solution was used instead of the 0.1N—LiOH aqueous solution. A potassium-substituted α-zirconium phosphate composed of 03H ₂ O was produced. The moisture content was 0.5%. This potassium-substituted α-zirconium phosphate is one in which 4 meq / g of all cation exchange capacities is replaced with lithium ions. Hereinafter, it was referred to as “4 meq-K substituted α-zirconium phosphate A1-3”.
Next, using the solar cell ion scavenger comprising 4meq-K-substituted α-zirconium phosphate A1-3, the above various evaluations were performed, and the results are shown in Table 1.

Example 4
Except that the amount of 0.1N KOH aqueous solution used was 2500 mL, the same operation as in Example 3 was performed, and all the cation exchange groups (cation exchange capacity: 6.7 meq / g) were replaced with potassium ions. In addition, potassium-substituted α-zirconium phosphate composed of ZrK _2.03 (PO ₄ ) _2.01 was produced. The moisture content was 0.4%. Hereinafter, it was referred to as “all K-substituted α-zirconium phosphate A1-4”.
Next, using the solar cell ion scavenger composed of this all-K-substituted α-zirconium phosphate A1-4, the above-mentioned various evaluations were performed, and the results are shown in Table 1.

Example 5
After dissolving 0.272 mol of zirconium oxychloride octahydrate with Hf content of 0.18% in 850 mL of deionized water, 0.788 mol of oxalic acid dihydrate was added and dissolved. I let you. While stirring this aqueous solution, 0.57 mol of phosphoric acid was added. This was refluxed at 98 ° C. for 8 hours with stirring. After cooling, the resulting precipitate was washed well with water, and then dried at 150 ° C. to obtain a scaly powder composed of zirconium phosphate. As a result of analyzing this zirconium phosphate, it was confirmed that it was α-zirconium phosphate (H type) (hereinafter referred to as “α-zirconium phosphate (Z2)”).
The above α-zirconium phosphate (Z2) was boiled and dissolved in nitric acid to which hydrofluoric acid was added, and then subjected to ICP emission spectroscopic analysis to obtain the following composition formula.
Zr _0.99 Hf _0.01 H _2.03 (PO ₄ ) _2.01 · 0.05H ₂ O
The median diameter of α-zirconium phosphate (Z2) was 0.8 μm.

Next, 25 g of α-zirconium phosphate (Z2) was added while stirring 1000 mL of a 0.1N-LiOH aqueous solution, and this was stirred for 8 hours. Thereafter, the precipitate was washed with water and vacuum-dried at 150 ° C. for 20 hours to obtain lithium composed of Zr _0.99 Hf _0.01 Li _1.03 H _1.00 (PO ₄ ) _2.01 · 0.2H ₂ O. An ion-substituted α-zirconium phosphate was produced. The water content by the Karl Fischer method was 0.4%. This lithium ion-substituted α-zirconium phosphate is one in which 4 meq / g of all cation exchange capacities is replaced with lithium ions. Hereinafter, it was referred to as “4 meq-Li substituted α-zirconium phosphate A2-1”.
Next, various evaluations described above were performed using the ion scavenger for solar cells composed of this 4 meq-Li substituted α-zirconium phosphate A2-1. The results are shown in Table 1.

Example 6
Except that the amount of 0.1N-LiOH aqueous solution used was 2500 mL, the same operation as in Example 5 was performed, and all the cation exchange groups (cation exchange capacity: 6.7 meq / g) were replaced with lithium ions. Further, lithium ion-substituted α-zirconium phosphate composed of Zr _0.99 Hf _0.01 Li _2.03 (PO ₄ ) _2.01 · 0.1H ₂ O was produced. The moisture content was 0.3%. Hereinafter, it was referred to as “all Li-substituted α-zirconium phosphate A2-2”.
Next, using the solar cell ion scavenger composed of all Li-substituted α-zirconium phosphate A2-2, the above various evaluations were performed. The results are shown in Table 1.

Example 7
Zr _0.99 Hf _0.01 K _1.03 H _1.00 (PO) was carried out in the same manner as in Example 5 except that a 0.1N-KOH aqueous solution was used instead of the 0.1N-LiOH aqueous solution. ₄ ) A potassium-substituted α-zirconium phosphate composed of _2.01 · 0.03H ₂ O was produced. The moisture content was 0.5%. This potassium-substituted α-zirconium phosphate is one in which 4 meq / g of all cation exchange capacities is replaced with lithium ions. Hereinafter, it was referred to as “4 meq-K substituted α-zirconium phosphate A2-3”.
Next, various evaluations described above were performed using the ion scavenger for solar cells composed of this 4 meq-K substituted α-zirconium phosphate A2-3, and the results are shown in Table 1.

Example 8
Except that the amount of 0.1N KOH aqueous solution used was 2500 mL, the same operation as in Example 7 was performed, and all the cation exchange groups (cation exchange capacity: 6.7 meq / g) were replaced with potassium ions. In addition, a potassium-substituted α-zirconium phosphate composed of Zr _0.99 Hf _0.01 K _2.03 (PO ₄ ) _2.01 was produced. The moisture content was 0.4%. Hereinafter, it was referred to as “all K-substituted α-zirconium phosphate A2-4”.
Next, using the solar cell ion scavenger composed of this all-K-substituted α-zirconium phosphate A2-4, the above various evaluations were performed. The results are shown in Table 1.

Example 9
The same operation as in Example 5 was performed except that 2500 mL of a 0.1 N—Rb ₂ CO ₃ aqueous solution was used instead of the 0.1 N—LiOH aqueous solution, and all cation exchange groups (cation exchange capacity: 6. A rubidium-substituted α-zirconium phosphate having 7 meq / g) substituted with rubidium ions was produced. The moisture content was 0.5%. Hereinafter, it was referred to as “all Rb-substituted α-zirconium phosphate A2-5”.
Next, using the solar cell ion scavenger composed of all Rb-substituted α-zirconium phosphate A2-5, the above various evaluations were performed, and the results are shown in Table 1.

Example 10
The same operation as in Example 5 was performed except that 2500 mL of a 0.1 N—Cs ₂ CO ₃ aqueous solution was used instead of the 0.1 N—LiOH aqueous solution, and all cation exchange groups (cation exchange capacity: 6. Cesium-substituted α-zirconium phosphate having 7 meq / g) substituted with cesium ions was produced. The moisture content was 0.4%. Hereinafter, it was referred to as “all Cs-substituted α-zirconium phosphate A2-6”.
Next, using the solar cell ion scavenger composed of all Cs-substituted α-zirconium phosphate A2-6, the above various evaluations were performed, and the results are shown in Table 1.

Example 11
The same procedure as in Example 5 was performed except that 2500 mL of 0.1N- (CH ₃ COO) ₂ Mg aqueous solution was used instead of the 0.1N-LiOH aqueous solution, and all cation exchange groups (cation exchange capacity) were obtained. : 6.7 meq / g) was substituted with magnesium ions to produce a magnesium-substituted α-zirconium phosphate. The moisture content was 0.5%. Hereinafter, it was referred to as “all Mg-substituted α-zirconium phosphate A2-7”.
Next, using the solar cell ion scavenger composed of this all-Mg-substituted α-zirconium phosphate A2-7, the above various evaluations were performed, and the results are shown in Table 1.

Example 12
All cation exchange groups (cation exchange capacities) were obtained in the same manner as in Example 5 except that 2500 mL of 0.1N— (CH ₃ COO) ₂ Ca aqueous solution was used instead of the 0.1N—LiOH aqueous solution. : 6.7 meq / g) of calcium-substituted α-zirconium phosphate in which calcium ions were substituted. The moisture content was 0.6%. Hereinafter, it was referred to as “total Ca-substituted α-zirconium phosphate A2-8”.
Next, using the solar cell ion scavenger composed of this all-Ca-substituted α-zirconium phosphate A2-8, the above-mentioned various evaluations were performed, and the results are shown in Table 1.

Example 13
405 g of 75% phosphoric acid was added to 400 mL of deionized water, and 137 g of titanyl sulfate (TiO ₂ equivalent content: 33%) was added while stirring the aqueous solution. This was refluxed at 100 ° C. for 48 hours with stirring. After cooling, the resulting precipitate was washed well with water and dried at 150 ° C. to obtain a scaly powder composed of titanium phosphate. As a result of analyzing this titanium phosphate, it was confirmed that it was α-titanium phosphate (H type).
The α-titanium phosphate was boiled and dissolved in nitric acid to which hydrofluoric acid was added, and then subjected to ICP emission spectroscopic analysis to obtain the following composition formula.
TiH _2.03 (PO ₄ ) _2.01 · 0.1H ₂ O
The median diameter of α-titanium phosphate was measured and found to be 0.7 μm.

Next, 25 g of α-titanium phosphate was added to 1000 mL of 0.1N-LiOH aqueous solution while stirring, and this was stirred for 8 hours. Thereafter, the precipitate was washed with water and vacuum-dried at 150 ° C. for 20 hours to obtain a lithium ion-substituted α-titanium phosphate composed of TiLi _1.03 H _1.00 (PO ₄ ) _2.01 · 0.2H ₂ O. Manufactured. The moisture content was 0.5%. This lithium ion-substituted α-titanium phosphate is one in which 4 meq / g of all cation exchange capacities is replaced with lithium ions. Hereinafter, it was referred to as “4 meq-Li substituted α-titanium phosphate B-1”.
Next, using the solar cell ion scavenger composed of this 4 meq-Li-substituted α-titanium phosphate B-1, the above-mentioned various evaluations were performed, and the results are shown in Table 1.

Example 14
Except that the amount of 0.1N-LiOH aqueous solution used was 2500 mL, the same operation as in Example 13 was performed to replace all cation exchange groups (cation exchange capacity: 7.0 meq / g) with lithium ions. Further, lithium ion-substituted α-titanium phosphate made of TiLi _2.03 (PO ₄ ) _2.01 · 0.1H ₂ O was produced. The moisture content was 0.4%. Hereinafter, it was referred to as “all Li-substituted α-titanium phosphate B-2”.
Next, using the solar cell ion scavenger composed of all Li-substituted α-titanium phosphate B-2, various evaluations described above were performed, and the results are shown in Table 1.

Example 15
The same operation as in Example 13 was carried out except that a 0.1N-KOH aqueous solution was used instead of the 0.1N-LiOH aqueous solution, and TiK _1.03 H _1.00 (PO ₄ ) _2.01 . A potassium ion-substituted α-titanium phosphate composed of 05H ₂ O was produced. The moisture content was 0.4%. Hereinafter, it was referred to as “4 meq-K substituted α-titanium phosphate B-3”.
Next, using the solar cell ion scavenger composed of this 4 meq-K substituted α-titanium phosphate B-3, various evaluations described above were carried out, and the results are shown in Table 1.

Example 16
Except that the amount of 0.1N KOH aqueous solution used was 2500 mL, the same operation as in Example 13 was performed, and all the cation exchange groups (cation exchange capacity: 7.0 meq / g) were replaced with potassium ions. Furthermore, potassium-substituted α-titanium phosphate composed of TiK _2.03 (PO ₄ ) _2.00 was produced. The moisture content was 0.5%. Hereinafter, it was referred to as “all K-substituted α-titanium phosphate B-4”.
Next, various evaluations described above were performed using this solar cell ion scavenger composed of all-K-substituted α-titanium phosphate B-4, and the results are shown in Table 1.

Example 17
The same operation as in Example 13 was performed except that 2500 mL of a 0.1 N—Rb ₂ CO ₃ aqueous solution was used instead of the 0.1 N—LiOH aqueous solution, and all cation exchange groups (cation exchange capacity: 7. A rubidium-substituted α-titanium phosphate having 0 meq / g) substituted with rubidium ions was produced. The moisture content was 0.4%. Hereinafter, it was referred to as “all Rb-substituted α-titanium phosphate B-5”.
Next, using the solar cell ion scavenger composed of this all-Rb-substituted α-titanium phosphate B-5, various evaluations described above were performed, and the results are shown in Table 1.

Example 18
The same operation as in Example 13 was performed except that 2500 mL of a 0.1 N—Cs ₂ CO ₃ aqueous solution was used instead of the 0.1 N—LiOH aqueous solution, and all cation exchange groups (cation exchange capacity: 7. A cesium-substituted α-titanium phosphate having 0 meq / g) substituted with cesium ions was produced. The moisture content was 0.5%. Hereinafter, it was referred to as “all Cs-substituted α-titanium phosphate B-6”.
Next, using the solar cell ion scavenger composed of all Cs-substituted α-titanium phosphate B-6, the above various evaluations were performed. The results are shown in Table 1.

Example 19
The same operation as in Example 13 was performed except that 2500 mL of 0.1N- (CH ₃ COO) ₂ Mg aqueous solution was used instead of the 0.1N-LiOH aqueous solution, and all cation exchange groups (cation exchange capacity) were obtained. : 7.0 meq / g) was substituted with magnesium ions to produce magnesium substituted α-titanium phosphate. The moisture content was 0.5%. Hereinafter, it was referred to as “total Mg-substituted α-titanium phosphate B-7”.
Next, various evaluations described above were performed using the ion scavenger for solar cells made of all Mg-substituted α-titanium phosphate B-7, and the results are shown in Table 1.

Example 20
The same procedure as in Example 13 was performed except that 2500 mL of 0.1 N— (CH ₃ COO) ₂ Ca aqueous solution was used instead of the 0.1 N—LiOH aqueous solution, and all cation exchange groups (cation exchange capacity) were obtained. : 7.0 meq / g) was substituted with calcium ions to produce calcium substituted α-titanium phosphate. The moisture content was 0.4%. Hereinafter, it was referred to as “total Ca-substituted α-titanium phosphate B-8”.
Next, using the solar cell ion scavenger composed of this all-Ca-substituted α-titanium phosphate B-8, various evaluations described above were performed, and the results are shown in Table 1.

Example 21
All Li-substituted α-zirconium phosphate A1-2 and all K-substituted α-zirconium phosphate A1-4 were mixed at a mass ratio of 1: 1 to obtain an ion scavenger for solar cells. And various said evaluation was performed and the result was shown in Table 1.

Example 22
Total Li-substituted α-zirconium phosphate A1-2 and total Li-substituted α-zirconium phosphate A2-2 were mixed at a mass ratio of 1: 1 to obtain an ion scavenger for solar cells. And various said evaluation was performed and the result was shown in Table 1.

Example 23
Total Li-substituted α-zirconium phosphate A1-2 and total K-substituted α-zirconium phosphate A2-4 were mixed at a mass ratio of 1: 1 to obtain an ion scavenger for solar cells. And various said evaluation was performed and the result was shown in Table 1.

Example 24
Total Li-substituted α-zirconium phosphate A1-2 and total Li-substituted α-titanium phosphate B-2 were mixed at a mass ratio of 1: 1 to obtain an ion scavenger for solar cells. And various said evaluation was performed and the result was shown in Table 1.

Example 25
All Li-substituted α-zirconium phosphate A1-2 and all K-substituted α-titanium phosphate B-4 were mixed at a mass ratio of 1: 1 to obtain an ion scavenger for solar cells. And various said evaluation was performed and the result was shown in Table 2.

Example 26
Total K-substituted α-zirconium phosphate A1-4 and total Li-substituted α-zirconium phosphate A2-2 were mixed at a mass ratio of 1: 1 to obtain an ion scavenger for solar cells. And various said evaluation was performed and the result was shown in Table 2.

Example 27
Total K-substituted α-zirconium phosphate A1-4 and total K-substituted α-zirconium phosphate A2-4 were mixed at a mass ratio of 1: 1 to obtain an ion scavenger for solar cells. And various said evaluation was performed and the result was shown in Table 2.

Example 28
Total K-substituted α-zirconium phosphate A1-4 and total Li-substituted α-titanium phosphate B-2 were mixed at a mass ratio of 1: 1 to obtain an ion scavenger for solar cells. And various said evaluation was performed and the result was shown in Table 2.

Example 29
Total K-substituted α-zirconium phosphate A1-4 and total K-substituted α-titanium phosphate B-4 were mixed at a mass ratio of 1: 1 to obtain an ion scavenger for solar cells. And various said evaluation was performed and the result was shown in Table 2.

Example 30
Total Li-substituted α-zirconium phosphate A2-2 and total K-substituted α-zirconium phosphate A2-4 were mixed at a mass ratio of 1: 1 to obtain an ion scavenger for solar cells. And various said evaluation was performed and the result was shown in Table 2.

Example 31
Total Li-substituted α-zirconium phosphate A2-2 and total Li-substituted α-titanium phosphate B-2 were mixed at a mass ratio of 1: 1 to obtain an ion scavenger for solar cells. And various said evaluation was performed and the result was shown in Table 2.

Example 32
Total Li-substituted α-zirconium phosphate A2-2 and total K-substituted α-titanium phosphate B-4 were mixed at a mass ratio of 1: 1 to obtain an ion scavenger for solar cells. And various said evaluation was performed and the result was shown in Table 2.

Example 33
Total K-substituted α-zirconium phosphate A2-4 and total Li-substituted α-titanium phosphate B-2 were mixed at a mass ratio of 1: 1 to obtain an ion scavenger for solar cells. And various said evaluation was performed and the result was shown in Table 2.

Example 34
Total K-substituted α-zirconium phosphate A2-4 and total K-substituted α-titanium phosphate B-4 were mixed at a mass ratio of 1: 1 to obtain an ion scavenger for solar cells. And various said evaluation was performed and the result was shown in Table 2.

Example 35
Total Li-substituted α-titanium phosphate B-2 and total K-substituted α-titanium phosphate B-4 were mixed at a mass ratio of 1: 1 to obtain an ion scavenger for solar cells. And various said evaluation was performed and the result was shown in Table 2.

Comparative Example 1
Various evaluations were performed using an inorganic ion exchanger “IXE100” (trade name) manufactured by Toagosei Co., Ltd., which is α-zirconium phosphate (H type) not substituted with a cation. The results are shown in Table 2.

Comparative Example 2
All cation exchange groups (cation exchange capacity: 6.7 meq / g) were carried out in the same manner as in Example 5 except that 2500 mL of 0.1N NaOH solution was used instead of 0.1N LiOH solution. Sodium substituted α-zirconium phosphate composed of Zr _0.99 Hf _0.01 Na _2.03 (PO ₄ ) _2.01 · 0.05H ₂ O, in which) is substituted with sodium ions. The moisture content was 0.5%. Hereinafter, it was referred to as “total Na-substituted α-zirconium phosphate”.
Next, using the solar cell ion scavenger composed of all Na-substituted α-zirconium phosphate, the above various evaluations were performed, and the results are shown in Table 2.

Comparative Example 3
Various evaluations were made using the α-titanium phosphate (H-type) prepared in Example 13 as it was. The results are shown in Table 2.

Comparative Example 4
All cation exchange groups (cation exchange capacity: 7.0 meq / g) were carried out in the same manner as in Example 13 except that 2500 mL of a 0.1 N NaOH aqueous solution was used instead of the 0.1 N LiOH aqueous solution. ) Was substituted with sodium ions, and sodium substituted α-titanium phosphate composed of TiNa _2.03 (PO ₄ ) _2.00 · 0.05H ₂ O was produced. The moisture content was 0.5%. Hereinafter, it was referred to as “total Na-substituted α-titanium phosphate”.
Next, using the solar cell ion scavenger composed of all Na-substituted α-titanium phosphate, the various evaluations described above were performed, and the results are shown in Table 2.

Comparative Example 5
A Y-type zeolite “Mizuka Sieves Y-520” (trade name) manufactured by Mizusawa Chemical Co., Ltd. was dried at 150 ° C. for 20 hours and then subjected to various evaluations. The results are shown in Table 2.

From Table 1 and Table 2, it can be seen that the ion scavengers for solar cells of Examples 1 to 35 have a high Na ⁺ ion trapping rate in an aqueous NaCl solution and the pH fluctuation is within 1. Also, in the extracted water after the crosslinked resin test piece was immersed in pure water, the ion scavengers for solar cells of Examples 1 to 35 exhibited high elution suppression performance of Na ⁺ ions. From these results, the ion scavenger of the present invention adsorbs Na ⁺ ions, which are considered to be the cause of solar cell PID, while there is no pH fluctuation, and therefore does not promote deterioration of the sealing resin. The PID of the solar cell can be suppressed.

The ion scavenger for solar cells of the present invention adsorbs Na ⁺ ions causing PID of solar cells with high selectivity and does not easily release H ⁺ ions. It can be made to contain in the member which forms a back surface side protection member. Thereby, the solar cell excellent in durability can be formed. It can also be used by adding to a silver electrode paste or the like.

10: Solar cell module, 11: Solar cell element, 13: Sealing layer, 15: Front side transparent protective member, 17: Back side protective member, 19: Interconnector

Claims

(A) α-zirconium phosphate in which at least part of the ion exchange group is substituted with at least one ion (a1) selected from lithium ion, potassium ion, cesium ion, rubidium ion, magnesium ion and calcium ion; (B) α-phosphoric acid in which at least a part of the ion exchange group is substituted with at least one ion (b1) selected from lithium ion, potassium ion, cesium ion, rubidium ion, magnesium ion and calcium ion An ion scavenger for solar cells, comprising at least one of titanium.
The solar cell ion according to claim 1, wherein the component (A) is α-zirconium phosphate in which 0.1 to 6.7 meq / g of the total ion exchange capacity is substituted with the ion (a1). Scavenger.
The ion scavenger for solar cells according to claim 1 or 2, wherein the α-zirconium phosphate before being substituted with the ion (a1) is a compound represented by the following formula (1).
Zr 1-x Hf x H a (PO 4) b · mH 2 O (1)
(In the formula, 0 ≦ x ≦ 0.2, 2 <b ≦ 2.1, a is a number satisfying 3b−a = 4, and 0 ≦ m ≦ 2.)
4. The component (B) is α-titanium phosphate in which 0.1 to 7.0 meq / g of the total ion exchange capacity is substituted with the ion (b1). The ion-trapping agent for solar cells described in 1.
The ion scavenger for solar cells according to any one of claims 1 to 4, wherein the α-titanium phosphate before being substituted with the ion (b1) is a compound represented by the following formula (2).
TiH s (PO 4 ) t · nH 2 O (2)
(In the formula, 2 <t ≦ 2.1, s is a number satisfying 3t−s = 4, and 0 ≦ n ≦ 2.)
A solar cell encapsulant composition comprising the solar cell ion scavenger according to any one of claims 1 to 5 and a resin.
The solar cell encapsulant composition according to claim 6, wherein the resin contains an ethylene / vinyl acetate copolymer resin.
The solar cell according to claim 6 or 7, wherein the solar cell element is between a solar cell element, a front surface side transparent protective member, a back surface side protective member, the front surface side transparent protective member, and the back surface side protective member. A solar cell module comprising: a sealing layer sealed with a sealing agent composition for use.