JP2011073348A - Filler sheet for solar cell module, and solar cell module using the same - Google Patents

Abstract

The present invention provides a solar cell module filler sheet excellent in adhesiveness and heat resistance, and a solar cell module using the same.
A solar cell module filler sheet comprising two or more resin layers, the resin layer having a first layer 1 and a second layer 2 on the first layer 1 as a first layer. Layer 1 includes a silane-modified resin and a non-silane-modified resin, the amount of the silane-modified resin is 3% by mass or more, and the second layer 2 has a density of 0.890 g / It is a solar cell module 11 using the filler sheet | seat for solar cell modules containing the metal adhesive resin of cm < ³ > or less, and the compounding quantity of metal adhesive resin is 10 mass% or more.
[Selection] Figure 1

Description

  The present invention relates to a solar cell module filler sheet and a solar cell module using the same, and more particularly to a solar cell module filler sheet excellent in adhesiveness and heat resistance and a solar cell module using the same.

  In recent years, solar cells as a clean energy source have attracted attention due to the growing awareness of environmental issues. Solar cell elements are often manufactured using a single crystal silicon substrate or a polycrystalline silicon substrate, so that the solar cell elements are vulnerable to physical shocks, and are protected from rain when solar cells are installed outdoors. There is a need to. Furthermore, since the electric output generated by one solar cell element is small, it is necessary to connect a plurality of solar cell elements in series and parallel so that a practical electric output can be taken out. For this reason, it is a common practice to produce a solar cell module by connecting a plurality of solar cell elements and enclosing them with a transparent substrate and a filler. In general, a solar cell module is manufactured using a lamination method or the like in which a transparent front substrate, a filler, a solar cell element, a filler, a back surface protective sheet, and the like are sequentially stacked, and these are vacuum-sucked and heat-pressed.

  Currently, as the filler, an adhesive force for bonding the solar cell element and the back surface protective sheet with sufficient strength is required, and from the viewpoint of protection of the solar cell element, durability, weather resistance, heat resistance It is required to be made of a resin excellent in various properties such as light resistance and water resistance. Therefore, in recent years, a silane-modified resin obtained by polymerizing an inorganic material such as glass and a silane-modified resin having an alkoxysilyl group that exhibits excellent adhesion, particularly an ethylenically unsaturated silane compound and a resin such as a polyolefin. Used (see Patent Document 1).

JP 2004-214641 A

  However, the alkoxysilyl group possessed by the silane-modified resin is easily hydrolyzed to form a silanol group in the presence of water, and the silanol group easily undergoes a condensation reaction by heating or the like to generate a siloxane group. It has been known. Furthermore, it is known that when water is present, the alkoxysilyl group involved in the adhesion of the solar cell element or the like is consumed as a siloxane group and the adhesiveness is lowered.

  Therefore, when moisture contacts the surface of the filler sheet using the silane-modified resin and is stored in a high-temperature environment, the alkoxysilyl groups decrease with the formation of siloxane groups. There was a problem that there was a risk of lowering. In addition, when a solar cell module is manufactured using such a filler sheet having reduced adhesiveness, there is a problem that a problem such as a decrease in electromotive force may occur in a short period of time.

  Then, the objective of this invention is providing the solar cell module using the filler sheet for solar cell modules excellent in adhesiveness and heat resistance, and it.

  As a result of intensive studies to solve the above problems, the present inventors can solve the above problems by using a filler sheet for a solar cell module having a resin layer containing a specific metal adhesive resin. As a result, the present invention has been completed.

That is, the solar cell module filler sheet of the present invention is a solar cell module filler sheet comprising two or more resin layers,
The resin layer has a first layer and a second layer on the first layer,
The first layer includes a silane-modified resin and a non-silane-modified resin, and the amount of the silane-modified resin is 3% by mass or more,
The second layer includes a non-silane-modified resin and a metal adhesive resin having a density of 0.890 g / cm ³ or less, and the compounding amount of the metal adhesive resin is 10% by mass or more. It is what.

Moreover, the solar cell module of the present invention comprises a back surface protection sheet,
A back surface filler sheet formed on the back surface protection sheet;
A solar cell element formed on the back surface filler sheet;
A front filler sheet formed on the solar cell element;
A transparent front substrate formed on the front filler sheet,
At least one of the front filler sheet and the back filler sheet is the solar cell module filler sheet.

  According to the present invention, it is possible to provide a solar cell module filler sheet excellent in adhesiveness and heat resistance and a solar cell module using the same.

It is the schematic which shows an example of the filler sheet for solar cell modules of this invention. It is the schematic which shows another example of the filler sheet for solar cell modules of this invention. It is the schematic which shows an example of the solar cell module of this invention.

  Hereinafter, the filler sheet for solar cell module and the solar cell module of the present invention will be described in detail.

  FIG. 1 is a schematic view showing an example of the solar cell module filler sheet of the present invention. As illustrated in FIG. 1, the solar cell module filler sheet 3 of the present invention is a solar cell module filler sheet composed of two or more resin layers, and further includes a first layer 1 as a resin layer, And a second layer 2 on the first layer 1.

According to the present invention, the resin layer is composed of two or more resin layers, and has a first layer 1 and a second layer 2 on the first layer 1 as the resin layer. A non-silane-modified resin, and the second layer 2 is a non-silane-modified resin and a metal adhesive resin having a density of 0.890 g / cm ³ or less. And the blending amount of the metal adhesive resin is 10% by mass or more, the solar cell module filler sheet of the present invention can be made excellent in adhesiveness and heat resistance. In the solar cell module, by using the first layer 1 on the transparent front (glass) substrate side and the second layer 2 on the solar cell element (cell) side, the front transparent substrate constituting the solar cell module, Product with sufficient adhesion strength with solar cell element and back protection sheet Furthermore, a solar cell module having excellent photoelectric conversion efficiency can be obtained. In addition, since the second layer 2 does not contain a silane-modified resin, hydrolysis of the alkoxysilyl group of the silane-modified resin in the second layer 2 and further formation of siloxane groups by condensation can be suppressed. Excellent adhesiveness can be maintained for a long time. Furthermore, since the second layer 2 includes a metal adhesive resin having a density of 0.890 g / cm ³ or less, blocking and generation of acidic gas are suppressed, and the second layer 2 has good heat resistance. Furthermore, when the second layer 2 is a non-silane-modified resin, a solar cell module filler sheet can be produced at low cost.

The second layer 2 used in the present invention includes a non-silane-modified resin and a metal adhesive resin having a density of 0.890 g / cm ³ or less, and the compounding amount of the metal adhesive resin is 10% by mass or more. Further, it is not particularly limited as long as it can transmit light through the solar cell element when used in a solar cell module.

The non-silane-modified resin contained in the second layer 2 used in the present invention is not particularly limited as long as it can adhere to the first layer 1 described later with sufficient strength, but preferably The density is 0.910 g / cm ³ or less, more preferably 0.870 g / cm ³ or more. By setting the density within such a range, the adhesiveness can be improved.

  Examples of the non-silane-modified resin include ethylene, propylene, 1-butene, isobutylene, 1-pentene, 2-methyl-1-butene, 3-methyl-1-butene, 1-hexene, 1-heptene, 1- Among α-olefins such as octene, 1-nonene and 1-decene, and other unsaturated monomers, those obtained by copolymerizing one type or two or more types can be used.

  Here, examples of the unsaturated monomer include vinyl esters such as vinyl acetate and vinyl propionate; methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, and isobutyl (meth) acrylate. , Unsaturated carboxylic acid esters such as n-butyl (meth) acrylate, isooctyl (meth) acrylate, dimethyl maleate; (meth) acrylic acid, fumaric acid, itaconic acid, monomethyl maleate, monoethyl maleate, maleic anhydride Examples thereof include unsaturated carboxylic acids such as acid and itaconic anhydride, and salts of unsaturated carboxylic acids, and styrene, (meth) acrylonitrile, vinyl alcohol, and the like may also be used. Examples of the unsaturated carboxylic acid salt include monovalent metals such as lithium, sodium and potassium, and salts of polyvalent metals such as magnesium, calcium and zinc.

  In the present invention, in particular, polyethylene, ethylene-vinyl alcohol copolymer, ethylene-unsaturated carboxylic acid ester copolymer, ethylene-unsaturated carboxylic acid copolymer, and the above ethylene-unsaturated carboxylic acid copolymer are sodium. An ionomer intermolecularly bonded with a metal salt such as zinc or zinc can be preferably used, and polyethylene can be more preferably used. As a result, no nasty smell or thermal decomposition products that corrode the electrodes constituting the solar cell module are generated during heating, and when the solar cell module is produced, the vacuum lamination method is used together with the solar cell element, etc. Thus, after laminating the respective constituent materials of the solar cell module, the thermal cross-linking step of heating and cross-linking becomes unnecessary, so that the solar cell module can be produced at low cost.

  The polyethylene is not particularly limited as long as it has desired light resistance, mechanical strength, transparency, and the like. Any of high-density polyethylene, medium-density polyethylene, low-density polyethylene, and linear low-density polyethylene can be used. Can also be suitably used.

  In the present invention, only one kind of the non-silane-modified resin may be used alone, or two or more kinds may be used in combination.

  Moreover, it is preferable that melting | fusing point of the said non-silane modified resin is 60 to 130 degreeC. It is because it is excellent in moldability at the time of manufacture of the solar cell module using the filler sheet for solar cell module. In addition, as a measuring method of melting | fusing point, based on the plastics transition temperature measuring method (JISK7121), it carries out by differential scanning calorimetry (DSC). At that time, when two or more melting points exist, the higher temperature is defined as the melting point.

  Furthermore, in the present invention, the non-silane-modified resin preferably has a melt mass flow rate at 190 ° C. of 0.5 g / 10 min to 10 g / 10 min, preferably 1 g / 10 min to 8 g / 10 min. Is more preferable. This is because the formability of the filler sheet for solar cell module of the present invention is excellent.

The metal adhesive resin contained in the second layer 2 used in the present invention has a density of 0.890 g / cm ³ or less, and preferably a density of 0.870 g / cm ³ or more. Thereby, blocking can be suppressed and heat resistance and adhesion to metal can be improved.

  Moreover, as a compounding quantity of the said metal adhesive resin, it is necessary to contain 10 mass% or more, Preferably it contains 15-40 mass%. By setting the blending amount within this range, blocking and generation of acidic gas can be suppressed, and heat resistance and adhesion to metal can be improved.

As said metal adhesive resin, maleic anhydride modified resin etc. can be mentioned, for example. Specific examples include Admer SF731 (manufactured by Mitsui Chemicals, Inc., density 0.880 g / cm ³ ), Admer SF730 (manufactured by Mitsui Chemicals, Inc., density 0.880 g / cm ³ ), and the like.

  The second layer 2 used in the present invention is not particularly limited as long as it contains the non-silane-modified resin and the metal adhesive resin, and may contain other additives. As said other additive, a light stabilizer, a ultraviolet absorber, or a heat stabilizer can be mentioned.

  As said light stabilizer, the active seed | species of the photodegradation start in the said 2nd layer 2 is trapped, and photooxidation is prevented. Specifically, one or a combination of two or more selected from hindered amine compounds, hindered piperidine compounds, and others can be used.

  As the ultraviolet absorber, harmful ultraviolet rays in sunlight are absorbed and converted into innocuous heat energy in the molecule, and the active species that initiate photodegradation in the second layer 2 is excited. It is to prevent. Specifically, benzophenone-based, benzotriazole-based, salicylate-based, acrylonitrile-based, metal complex-based, hindered amine-based, and ultrafine titanium oxide (particle diameter: 0.01 μm to 0.06 μm) or ultrafine zinc oxide (particles) At least one selected from the group consisting of inorganic ultraviolet absorbers such as (diameter: 0.01 μm to 0.04 μm) can be used.

  Examples of the heat stabilizer include tris (2,4-di-tert-butylphenyl) phosphite, bis [2,4-bis (1,1-dimethylethyl) -6-methylphenyl] ethyl ester phosphorous acid. Acid, tetrakis (2,4-di-tert-butylphenyl) [1,1-biphenyl] -4,4′-diylbisphosphonite, and bis (2,4-di-tert-butylphenyl) pentaerythritol Phosphorus heat stabilizers such as diphosphite; and lactone heat stabilizers such as a reaction product of 8-hydroxy-5,7-di-tert-butyl-furan-2-one and o-xylene. it can. Moreover, these can also use 1 type or 2 types or more. In particular, it is preferable to use a phosphorus-based heat stabilizer and a lactone-based heat stabilizer in combination.

  The content of the light stabilizer, ultraviolet absorber, heat stabilizer and the like in the present invention varies depending on the particle shape, density, etc., but in the solar cell module filler sheet 3, 0.01 mass% to 5 mass. % Is preferable.

  As thickness of the 2nd layer 2 used for this invention, when it is set as a solar cell module, it is preferable to show sufficient transparency, Therefore, it is preferable to exist in the range of 50 micrometers-1000 micrometers, 150 micrometers-600 micrometers. More preferably it is.

  The first layer 1 used in the present invention contains a silane-modified resin and a non-silane-modified resin, and the blending amount of the silane-modified resin is 3% by mass or more. When the first layer 1 contains a silane-modified resin, excellent adhesion to the front transparent substrate, the solar cell element, and the back surface protective sheet can be maintained for a long period of time.

  The silane-modified resin used in the present invention is not particularly limited as long as it contains an alkoxysilyl group. In the present invention, the non-silane-modified resin of the second layer 2, the silane-modified resin, However, it is preferable that they are the same kind of resin. The solar cell module filler sheet 3 of the present invention can be produced at low cost, and the adhesiveness between the first layer 1 and the second layer 2 can be improved.

  As the silane-modified resin used in the present invention, for example, a silane-modified copolymer obtained by copolymerizing an ethylenically unsaturated silane compound and a polymerization resin can be used. Such a silane-modified copolymer is preferably used in that it is easy to adjust various physical properties by changing the type and amount of the above-mentioned polymerization resin or ethylenically unsaturated silane compound as needed. Can do.

  In addition, the silane-modified copolymer used in the present invention is not particularly limited as long as it is a copolymer of an ethylenically unsaturated silane compound described later and a polymerization resin. For example, random copolymerization Even those formed by any copolymerization method of alternating copolymerization, block copolymerization, and graft copolymerization can be suitably used. In the present invention, it is particularly preferable to use a graft copolymerized product, and more preferably a graft copolymerized polymer having a polymerization resin as a main chain and an ethylenically unsaturated silane compound as a side chain. This is because the degree of freedom of the alkoxysilyl group contributing to the adhesive force is increased, and thus the adhesive force of the solar cell module filler sheet 3 can be further strengthened.

  Examples of the ethylenically unsaturated silane compound used in such a silane-modified copolymer include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltripropoxysilane, vinyltriisopropoxysilane, vinyltributoxysilane, and vinyltrimethoxysilane. Mention may be made of pentyloxysilane, vinyltriphenoxysilane, vinyltribenzyloxysilane, vinyltrimethylenedioxysilane, vinyltriethylenedioxysilane, vinylpropionyloxysilane, vinyltriacetoxysilane, or vinyltricarboxysilane. . In the present invention, in particular, vinylmethoxysilane can be preferably used. It is because it is excellent in the polymerization reactivity with the resin for polymerization mentioned later.

  As the ethylenically unsaturated silane compound used in the present invention, only one type may be used alone, or two or more types may be used.

  The polymerization resin used in the silane-modified copolymer is not particularly limited as long as it can be polymerized with the ethylenically unsaturated silane compound. For example, the second layer 2 non-silane-modified resins and monomers constituting the same can be used.

  Furthermore, in the present invention, it is preferable to use polyethylene among the non-silane-modified resins of the second layer 2 described above. Thus, as described above, during heating, there is no off-flavor or thermal decomposition products that corrode the electrodes constituting the solar cell module, and when producing solar cell modules, solar cell elements, etc. At the same time, after the constituent materials of the solar cell module are laminated by a vacuum lamination method or the like, a heating / crosslinking step of heating / crosslinking becomes unnecessary, and thus the solar cell module can be produced at low cost.

  In the present invention, one kind of the above polyethylene may be used as a simple substance, or two or more kinds may be mixed and used.

  The content of the ethylenically unsaturated silane compound in the silane-modified copolymer used in the present invention is preferably in the range of 0.001 to 4 parts by mass with respect to 100 parts by mass of the polymerization resin. In particular, it is preferably within the range of 0.01 to 3 parts by mass. If the amount is less than the above range, the adhesion to the transparent electrode substrate, the solar cell element and the back surface protective sheet may be insufficient. On the other hand, if the amount is more than the above range, the adhesion does not change and the cost may increase. is there.

  The melting point of the silane-modified copolymer is preferably 60 ° C to 110 ° C. It is because it is excellent in moldability at the time of manufacture of the solar cell module using the filler sheet 3 for solar cell modules. In addition, as a measuring method of melting | fusing point, the method similar to the above can be used.

  The silane-modified copolymer is not particularly limited as long as it has a melting point in the above range, but a melt mass flow rate at 190 ° C. is 0.5 g / 10 min to 10 g / 10 min. What is preferably 1 g / 10 min to 8 g / 10 min is more preferable. This is because the moldability of the solar cell module filler sheet 3 of the present invention can be improved. In addition, as a measurement of a melt mass flow rate, the method similar to the above can be used.

  The method for producing the silane-modified copolymer used in the present invention is not particularly limited as long as a silane-modified copolymer having a desired amount of alkoxysilyl group can be obtained. Examples thereof include a method in which an ethylenically unsaturated silane compound and the above-mentioned polymerization resin are heated and melted together with a radical polymerization initiator. The heat-melt mixing method is not particularly limited as long as it can be heat-melted and mixed under desired temperature conditions and the like, and a known heat-melt mixing device such as an extruder can be used. Further, the heating temperature in the method for producing the silane-modified copolymer is different depending on the material such as the ethylenically unsaturated silane compound to be used, but is preferably in the range of 150 ° C. to 300 ° C., 180 ° C. It is preferable to be in the range of ˜270 ° C. This is because the silane-modified copolymer is easily gelled due to crosslinking of the silanol group portion by heating.

  Examples of the radical polymerization initiator include hydroperoxides such as diisopropylbenzene hydroperoxide and 2,5-dimethyl-2,5-di (hydroperoxy) hexane; di-t-butyl peroxide, t -Butylcumyl peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (t-peroxy) hexyne-3 Dialkyl peroxides such as bis-3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, benzoyl peroxide, o-methylbenzoyl peroxide, 2,4-dichlorobenzoyl peroxide Class: t-butyl peroxyacetate, t-butyl peroxyacetate Oxy-2-ethylhexanoate, t-butyl peroxypivalate, t-butyl peroxyoctoate, t-butyl peroxyisopropyl carbonate, t-butyl peroxybenzoate, di-t-butyl peroxyphthalate, 2 Peroxyesters such as 1,5-dimethyl-2,5-di (benzoylperoxy) hexane and 2,5-dimethyl-2,5-di (benzoylperoxy) hexyne-3; methyl ethyl ketone peroxide, cyclohexanenonper Examples thereof include organic peroxides such as ketone peroxides such as oxides, or azo compounds such as azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile).

  The content of the radical polymerization initiator is not particularly limited as long as it can polymerize the ethylenically unsaturated silane compound and the polymerization resin, but the ethylenically unsaturated silane compound and It is preferable that 0.001 mass%-0.1 mass% is contained in the mixture of the said resin for superposition | polymerization. If it is less than the said range, radical polymerization with the said ethylenically unsaturated silane compound and the said resin for polymerization may not occur easily.

  Moreover, in this invention, the compounding quantity of the silane modified resin of the 1st layer 1 is 3 mass% or more. By setting the blending amount in such a range, excellent adhesion with the front transparent substrate, the solar cell element, and the back surface protective sheet can be maintained for a long time.

Furthermore, the silane-modified resin contained in the first layer 1 used in the present invention preferably has a density of 0.910 g / cm ³ or less, more preferably 0.870 g / cm ³ or more. By setting the density within such a range, the adhesiveness can be improved.

  As the non-silane-modified resin of the first layer 1 used in the present invention, the same resin as that of the second layer 2 can be used.

  The first layer 1 used in the present invention is not particularly limited as long as it contains a silane-modified resin and a non-silane-modified resin. For example, the first layer 1 contains an additive resin and other additives. It may be.

  The additive resin used in the present invention is not particularly limited as long as it can be uniformly mixed with the silane-modified resin and the non-silane-modified resin, but the silane-modified resin and the non-silane-modified resin are not limited. It is preferable to use the same resin used for polymerization. Cost reduction can be achieved by using such an additive resin.

  In the present invention, the content of the additive resin is preferably in the range of 0.01 to 9900 parts by mass with respect to a total of 100 parts by mass of the silane-modified resin and the non-silane-modified resin. Within the range of parts by mass to 2000 parts by mass is preferable. If the content of the additive resin is less than the above range, it may be disadvantageous in terms of cost. On the other hand, if the content is more than the above range, the solar cell module filler sheet 3 of the present invention is bonded. This is because power may become insufficient.

  The melting point of the additive resin is preferably 60 ° C to 130 ° C. It is because it is excellent in moldability at the time of manufacture of the solar cell module using the filler sheet 3 for solar cell modules.

  In the present invention, the additive resin preferably has a melt mass flow rate at 190 ° C. of 0.5 g / 10 min to 10 g / 10 min, more preferably 1 g / 10 min to 8 g / 10 min. . It is because it is excellent in the moldability of the filler sheet 3 for solar cell modules of this invention.

  Examples of other additives contained in the first layer 1 used in the present invention include a light stabilizer, an ultraviolet absorber, a heat stabilizer, and the like. it can. However, the ultraviolet absorber does not include a metal complex salt, an inorganic type such as ultrafine titanium oxide or ultrafine zinc oxide. This is because the inorganic ultraviolet absorber has a hygroscopic property, so that the adhesiveness of the first layer 1 may be lowered.

  Moreover, it is preferable that the 1st layer 1 used for this invention does not contain a silanol condensation catalyst substantially. This is because the silanol condensation catalyst promotes the condensation reaction between the silanol groups, so that the adhesiveness of the first layer 1 may be reduced in a short period of time. Note that the silanol condensation catalyst substantially does not contain the silanol condensation catalyst, specifically, a silanol condensation catalyst such as dibutyltin diacetate, dibutyltin dilaurate, dibutyltin dioctate, or dioctyltin dilaurate constitutes the first layer 1. The amount is preferably 0.05 parts by mass or less, more preferably in the range of 0 to 0.01 parts by mass, and even more preferably 0 parts by mass with respect to 100 parts by mass of the total resin. .

  The Si (silicon) content in the first layer 1 used in the present invention is preferably in the range of 8 ppm to 3500 ppm, more preferably in the range of 10 ppm to 3000 ppm, and particularly in the range of 50 ppm to 2000 ppm. Even more preferably within. When the amount of Si is less than the above range, the adhesive strength of the solar cell module filler sheet 3 of the present invention becomes insufficient, and there is a possibility that a solar cell module excellent in adhesive temporal stability cannot be produced. On the other hand, if the amount of Si is larger than the above range, it may be disadvantageous in terms of cost. Here, the amount of the polymerized Si is determined by ICP emission analysis using a high-frequency plasma emission analyzer (ICPS8100 manufactured by Shimadzu Corporation) after the ash content of the resin sheet is alkali-melted and dissolved in pure water. This is a value measured by quantifying the amount of polymerized Si.

  Further, the gel fraction of the silane-modified resin of the first layer 1 used in the present invention is preferably 30% or less, more preferably 10% or less, and even more preferably 0%. For example, when the solar cell module is formed using the solar cell module filler sheet 3 including the first layer 1, the solar cell module filler sheet 3 may be reused. This is because it becomes easy. On the other hand, if the gel fraction is higher than the above range, the workability during the production of the solar cell module may be reduced, or the adhesion strength with the transparent electrode substrate, the solar cell element and the back surface protective sheet may be insufficient. It is.

  As a method for measuring such a gel fraction, 1 g of silane-modified resin is weighed and placed in an 80 mesh wire mesh bag. Next, a sample with the wire mesh is put into a Soxhlet extractor, and xylene is refluxed at the boiling point. After 10 hours of continuous extraction, a method is used in which the sample is taken out together with the wire mesh, weighed after the drying process, mass comparison before and after extraction is performed, the mass% of residual insoluble matter is measured, and this is used as the gel fraction.

  Although it will not specifically limit as thickness of the 1st layer 1 used for this invention if it can show sufficient adhesiveness etc. when it is set as a solar cell module, It is the range of 5 micrometers-500 micrometers. It is preferable that it is inside, and it is further more preferable that it is 20 micrometers-150 micrometers.

  The solar cell module filler sheet 3 of the present invention comprises two or more resin layers, and the number of resin layers is particularly limited as long as the resin layer includes the first layer 1 and the second layer 2. If the desired effect of the present invention is obtained, two or more layers may be provided under the first layer 1.

  FIG. 2 is a schematic view showing another example of the solar cell module filler sheet of the present invention. The solar cell module filler sheet 3 shown in FIG. 2 has a three-layer structure having a third layer 4 as a lower layer of the first layer 1. The third layer 4 includes a silane-modified resin and a non-silane-modified resin as in the first layer 1, and the same silane-modified resin and non-silane-modified resin as described above can be used. Moreover, it is preferable that the 3rd layer 4 is 10-30 mass% of compounding quantities of silane modified resin. Thereby, adhesiveness can be maintained favorable.

  In addition, the thickness of the solar cell module filler sheet 3 of the present invention is not particularly limited as long as it can exhibit sufficient strength and the like when used as a solar cell module. It is preferably in the range of 1000 μm, more preferably 100 μm to 800 μm.

  The method for producing the solar cell module filler sheet 3 of the present invention is particularly limited as long as the first layer 1 and the second layer 2 can be laminated with good adhesion. Instead, for example, after each material of the first layer 1 and the second layer 2 is independently formed by a film forming method such as an extrusion method, a cast molding method, a T-die method, a cutting method, and an inflation method, A method for stacking, or a filler for a solar cell module in which each material of the first layer 1 and the second layer 2 is formed by co-extrusion film formation, and the first layer 1 and the second layer 2 are stacked. A method for producing the sheet 3 can be mentioned. Further, for example, a tenter method, a tubular method, or the like may be used to extend in a uniaxial or biaxial direction.

  FIG. 3 is a schematic view showing an example of the solar cell module of the present invention. The solar cell module 11 of the present invention includes a back surface protection sheet 12, a back surface filler sheet 13 formed on the back surface protection sheet 12, a solar cell element 14 formed on the back surface filler sheet 13, and a solar cell. A front filler sheet 15 formed on the element 14 and a transparent front substrate 16 formed on the front filler sheet 15, wherein at least one of the front filler sheet 15 and the back filler sheet 13 is The solar cell module filler sheet 3 is characterized by the above.

  In the solar cell module 11 of the present invention, the front filler sheet 15 is preferably the solar cell module filler sheet 3, and the front filler sheet 15 and the back filler sheet 13 are the solar cell module. The filler sheet 3 is preferably used.

  According to the present invention, by using the solar cell module filler sheet 3, the transparent front substrate 16, the solar cell element 14, and the back surface protective sheet 12 can be stably laminated with sufficient adhesion strength. Can do.

  Further, the gel fraction of the solar cell module filler sheet 3 included in the solar cell module 11 of the present invention is preferably 30% or less, more preferably 10% or less, and 0%. Is even more preferred. If the temperature is higher than the above range, for example, it becomes difficult to reuse the solar cell module filler sheet 3 after forming the solar cell module 11 using the solar cell module filler sheet 3. . Moreover, it is because the contact | adhesion intensity | strength with the transparent front substrate 16, the solar cell element 14, and the back surface protection sheet 12 may become inadequate.

As the solar cell element 14 used in the present invention, a general solar cell element 14 can be used. Specifically, crystalline silicon solar electronic elements such as single crystal silicon type solar cell elements and polycrystalline silicon type solar cell elements, amorphous silicon solar electronic elements composed of single junction type or tandem structure type, gallium arsenide (GaAs), etc. III-V group compound semiconductor solar electronic devices such as indium phosphorus (InP), II-VI group compound semiconductor solar electronic devices such as cadmium telluride (CdTe) and copper indium selenide (CuInSe ₂ ), organic solar cell devices and the like are used. be able to.

  As the solar cell element 14 used in the present invention, a thin film polycrystalline silicon solar cell element, a thin film microcrystalline silicon solar cell element, a hybrid element of a thin film crystalline silicon solar cell element and an amorphous silicon solar cell element, etc. Can be used.

  The back protective sheet 12 used in the present invention is not particularly limited as long as it has desired weather resistance such as heat resistance, light resistance, and water resistance. As such a back surface protection sheet 12, an insulating resin film, a metal plate, etc. are used suitably, for example. In particular, in the present invention, it is preferable to use the insulating resin film.

  Examples of the resin film include polyethylene resin, polypropylene resin, cyclic polyolefin resin, fluorine resin, polystyrene resin, acrylonitrile-styrene copolymer (AS resin), acrylonitrile-butadiene-styrene copolymer (ABS). Resin), polyvinyl chloride resin, fluorine resin, poly (meth) acrylic resin, polycarbonate resin, polyester resins such as polyethylene terephthalate and polyethylene naphthalate, polyamide resins such as various nylons, polyimide resins, Polyamideimide resin, polyarylphthalate resin, silicone resin, polysulfone resin, polyphenylene sulfide resin, polyethersulfone resin, polyurethane resin, acetal resin, cellulose Mention may be made of a film made of fat. In particular, in the present invention, it is preferable to use a film made of a fluorine resin, a cyclic polyolefin resin, a polycarbonate resin, a poly (meth) acrylic resin, or a polyester resin.

  Moreover, as such a resin film, a biaxially stretched resin film can also be used.

  Further, the resin film may have a configuration in which a plurality of films are laminated. Examples of the configuration in which such a plurality of films are laminated include a configuration in which a gas barrier film having an inorganic vapor deposition film is laminated, and a configuration in which a tough film is laminated.

  As thickness of the back surface protection sheet 12 used for this invention, it is preferable that it is normally in the range of 12 micrometers-200 micrometers, and it is still more preferable that it is in the range of 25 micrometers-150 micrometers.

  The transparent front substrate 16 used in the present invention is not particularly limited as long as it is a substrate having sunlight permeability. For example, a glass plate, a fluorine resin, a polyamide resin (various nylons), a polyester resin, Various resin films such as polyethylene resin, polypropylene resin, cyclic polyolefin resin, polystyrene resin, (meth) acrylic resin, polycarbonate resin, acetal resin, and cellulose resin can be used.

  In addition, the thickness of the transparent front substrate 16 used in the present invention is not particularly limited as long as the desired strength can be achieved, but usually it is preferably in the range of 12 μm to 7000 μm, particularly in the range of 25 μm to 4000 μm. preferable.

  In the solar cell module 11 of the present invention, other layers can be arbitrarily added and laminated on the basis of solar absorptivity, reinforcement, and other purposes. Examples of such other layers include low density polyethylene, medium density polyethylene, high density polyethylene, linear low density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer resin, ethylene. -Ethyl acrylate copolymer, ethylene-acrylic acid or methacrylic acid copolymer, methyl pentene polymer, polybutene resin, polyvinyl chloride resin, polyvinyl acetate resin, polyvinylidene chloride resin, vinyl chloride-vinylidene chloride Copolymer, Poly (meth) acrylic resin, Polyacrylonitrile resin, Polystyrene resin, Acrylonitrile-styrene copolymer (AS resin), Acrylonitrile-butadiene-styrene copolymer (ABS resin), Polyester Resin, polyamide system From films or sheets of known resins such as fats, polycarbonate resins, polyvinyl alcohol resins, saponified ethylene-vinyl acetate copolymers, fluorine resins, diene resins, polyacetal resins, polyurethane resins, nitrocellulose, etc. It can be arbitrarily selected and used.

  In the present invention, after laminating the transparent front substrate 16, the front filler sheet 15, the solar cell element 14, the back filler sheet 13, and the back surface protective sheet 12 in this order, as a method for thermocompression bonding these, The method is not particularly limited as long as the structure can be closely attached, and generally known methods can be used. As such a method, for example, the transparent front substrate 16, the front filler sheet 15, the solar cell element 14, the back filler sheet 13, and the back protective sheet 12 are laminated in this order, and then these are integrated into a vacuum. The lamination method etc. which are attracted | sucked and thermocompression-bonded can be illustrated.

  In general, the lamination temperature when using the above lamination method is preferably within a range of 90 ° C to 230 ° C, and particularly preferably within a range of 110 ° C to 190 ° C.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

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

[Example 1]
(Preparation of silane-modified resin 1)
With respect to 98 parts by mass of metallocene linear low density polyethylene (hereinafter referred to as “M-LLDPE”) having a density of 0.898 g / cm ³ and a melt mass flow rate at 190 ° C. of 2 g / 10 min. Then, 2 parts by mass of vinyltrimethoxysilane and 0.1 part by mass of dicumyl peroxide as a radical initiator were mixed, and heated and dissolved and stirred at 200 ° C. to obtain a silane-modified resin 1.

(Preparation of additive masterbatch)
For 85 parts by mass of M-LLDPE, 2.5 parts by mass of a hindered amine light stabilizer (manufactured by Ciba Japan, Tinuvin 770 DF), 7.5 parts by mass of a benzophenone-based ultraviolet absorber (manufactured by Sumitomo Chemical Co., Ltd., Sumisorb 130), An additive master batch was prepared by mixing, melting, processing and pelletizing 5 parts by mass of a phosphorus-based heat stabilizer (Irgafos 168, manufactured by Ciba Japan Co., Ltd.).

(Preparation of filler sheet for solar cell module)
In the production of the solar cell module filler sheet, a φ25 mm extruder capable of forming two types and two layers and a film molding machine having a 300-mm-wide T die were used. The resin in the hopper A is supplied to the first layer, and the resin in the hopper B is supplied to the second layer.

  First, 20 parts by mass of the silane-modified resin 1, 80 parts by mass of M-LLDPE, and 5 parts by mass of an additive master batch were mixed and charged into the hopper A of the film molding machine.

  Next, 85 parts by mass of the M-LLDPE, 5 parts by mass of the additive masterbatch, and 10 parts by mass of Admer SF731 (manufactured by Mitsui Chemicals) were mixed and charged into the hopper B of the film molding machine.

  Next, using the film molding machine, a sheet having a thickness of 400 μm at an extrusion temperature of 230 ° C. and a take-off speed of 3 m / min is formed so that the first layer has a thickness of 200 μm and the second layer has a thickness of 200 μm. Thus, a solar cell module filler sheet having a first layer and a second layer was obtained. In addition, said film formation was able to be implemented without trouble.

[Example 2]
A solar cell module filler sheet was obtained in the same manner as in Example 1 except that Admer SF730 (Mitsui Chemicals) was used instead of Admer SF731 (Mitsui Chemicals). .

[Comparative Example 1]
Filler for solar cell module in the same manner as in Example 1 except that a metal adhesive resin having a density exceeding 0.890 g / cm ³ was used instead of Admer SF731 (manufactured by Mitsui Chemicals, Inc.) in Example 1. A sheet was obtained.

[Comparative Example 2]
A solar cell module filler sheet was obtained in the same manner as in Example 1 except that the amount of Admer SF731 (manufactured by Mitsui Chemicals, Inc.) in Example 1 was 9 parts by mass.

(Measurement of adhesion)
In the vacuum laminator for solar cell module manufacture, the metal adhesive surface side and the 1 mm thick nickel plate were in contact with the solar cell module filler sheet obtained in Examples 1 and 2 and Comparative Examples 1 and 2. Crimped at 150 ° C for 15 minutes, stored in an environment of 85 ° C and 85RH%, and after storage for 500 hours, 1000 hours, 1500 hours, and 2000 hours, adherence (peeling) in 15 mm width according to JIS Z 1707 Strength) (unit: N / 15 mm) was measured. The measurement results are shown in Table 1.

[Example 3]
(Preparation of silane-modified resin 2)
100 parts by mass of linear low density polyethylene (hereinafter referred to as “LLDPE”) having a density of 0.898 g / cm ³ , 2.5 parts by mass of vinyltrimethoxysilane, and dicumyl peroxide as a radical initiator 0.1 part by mass was mixed and heated, dissolved and stirred at 200 ° C. to obtain a silane-modified resin 2.

(Preparation of weathering agent master batch)
3.75 parts by mass of benzotriazole-based ultraviolet absorber (Ciba Japan, Tinuvin 234), 3.75 parts by mass of hindered amine light stabilizer (Ciba Japan, Tinuvin 770 DF) with respect to 100 parts by mass of LLDPE, phosphorus A weathering agent master batch was prepared by mixing 0.5 parts by mass of a system heat stabilizer (Irgafos 168, manufactured by Ciba Japan Co., Ltd.), melting, processing and pelletizing.

(Preparation of filler sheet for solar cell module)
As a polyethylene for addition, 85 parts by mass of LLDPE having a density of 0.898 g / cm ³ , 10 parts by mass of Admer SF731 (manufactured by Mitsui Chemicals) and 5 parts by mass of the above weathering agent master batch are used as the material for the second layer, On the other hand, with respect to 20 parts by mass of the silane-modified resin 2, a mixture of 80 parts by mass of LLDPE having a density of 0.898 g / cm ³ as a polyethylene for addition and 5 parts by mass of the weathering agent master batch is used as the first layer material. did. The second layer material and the first layer material are separately fed into the hopper B and the hopper A of the above-described φ25 mm extruder and film molding machine having a 300-mm-wide T-die, the extrusion temperature is 230 ° C., and the take-off speed is 1. A solar cell module filler sheet having a total thickness of 600 μm was obtained at 8 m / min.

(Production of pseudo solar cell module)
For the solar cell module, arranged on a heater of a vacuum laminator for manufacturing a solar cell module, with a white plate tempered glass having a thickness of 3 mm and a size of 25 cm × 25 cm, and a first layer side being a crystalline Si solar cell element A crystalline Si solar cell element with a thickness of 180 μm and a size of 125 mm × 125 mm, which is provided with a filler sheet and lead wires attached to the front and back sides to allow power extraction, and the first layer side becomes a crystalline Si solar cell element The solar cell module filler sheet placed in the above was sequentially laminated, evacuated at 150 ° C. for 5 minutes, and then pressed for 13 minutes to produce a pseudo solar cell module.

[Examples 4 and 5]
The same silane-modified resin and weathering agent master batch as in Example 3 were used. In addition, the type, amount, and density of the additive polyethylene used in the first layer and the mixing ratio with the silane-modified resin, and the type, amount, and density of polyethylene used in the second layer are in accordance with the conditions in Table 2 below. A solar cell module filler sheet was produced in the same manner as in Example 3. A pseudo solar cell module was produced by the same method as in Example 3.

  In any of the examples, a pseudo solar cell module having no appearance of cracking of the solar cell element, no wrinkles of the filler, and good appearance was obtained. In addition, sufficient insulation was obtained without exposure of lead wires to the back side of the pseudo solar cell module. Furthermore, even after the obtained pseudo solar cell module was left for 3500 hours in an environment of a temperature of 85 ° C. and a humidity of 85%, in the pseudo solar cell modules of Examples 3 to 5, generation of rust and the like in the lead portion No good appearance was maintained. Moreover, the generation | occurrence | production of blocking and acidic gas was suppressed, and the solar cell module filler sheet which has favorable heat resistance was obtained.

DESCRIPTION OF SYMBOLS 1 1st layer 2 2nd layer 3 Filler sheet | seat for solar cell modules 4 3rd layer 11 Solar cell module 12 Back surface protection sheet 13 Back surface material sheet 14 Solar cell element 15 Front surface material sheet 16 Transparent front substrate

Claims (9)

A solar cell module filler sheet comprising two or more resin layers,
The resin layer has a first layer and a second layer on the first layer,
The first layer includes a silane-modified resin and a non-silane-modified resin, and the amount of the silane-modified resin is 3% by mass or more,
The second layer includes a non-silane-modified resin and a metal adhesive resin having a density of 0.890 g / cm ³ or less, and the compounding amount of the metal adhesive resin is 10% by mass or more. A solar cell module filler sheet. As a lower layer of the first layer, has a third layer,
2. The solar cell module filler sheet according to claim 1, wherein the third layer includes a silane-modified resin and a non-silane-modified resin, and a blending amount of the silane-modified resin is 10 to 30% by mass. The solar cell module filler sheet according to claim 1 or 2, wherein the density of the silane-modified resin and the non-silane-modified resin is 0.910 g / cm ³ or less, respectively.   The filler sheet for a solar cell module according to any one of claims 1 to 3, wherein the metal adhesive resin is a maleic anhydride-modified resin.   The gel fraction of the said silane modified resin is 30% or less, The filler sheet for solar cell modules as described in any one of Claims 1-4. The silane-modified resin is a silane-modified copolymer obtained by copolymerizing an ethylenically unsaturated silane compound and a polymerization resin, and the polymerization resin is polyethylene,
The solar cell module filler sheet according to any one of claims 1 to 5, wherein the silane-modified resin is polyethylene. A back protection sheet,
A back surface filler sheet formed on the back surface protection sheet;
A solar cell element formed on the back surface filler sheet;
A front filler sheet formed on the solar cell element;
A transparent front substrate formed on the front filler sheet,
7. The solar cell module according to claim 1, wherein at least one of the front filler sheet and the back filler sheet is a solar cell module filler sheet according to claim 1.   The solar cell module according to claim 7, wherein the front filler sheet is a solar cell module filler sheet according to claim 1.   The solar cell module according to claim 7, wherein the front filler sheet and the back filler sheet are solar cell module filler sheets according to claim 1.

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