JP2012149152A - Polyvinylidene fluoride resin composition, colored resin film, and backsheet for solar cell module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyvinylidene fluoride (PVDF) resin composition which improves the heat resistance of PVDF resin, and is suppressed in thermal decomposition and thermal discoloration even when a large amount of colorant is contained in the PVDF resin.SOLUTION: A backsheet for a solar cell module includes: the PVDF resin composition containing 0.5-70 pts.wt of talc as a thermal stabilizer, more preferably 2-60 pts.wt of the colorant and 2-60 pts.wt of the talc (colorant:talc=20:1-1:20), based on 100 pts.wt of the PVDF resin; a colored resin film formed of the PVDF resin composition; and a layer consisting of the colored resin film.

Description

  The present invention includes talc as a heat stabilizer, and preferably a polyvinylidene fluoride resin composition further containing a colorant, a colored resin film formed from the resin composition, and a layer comprising the colored resin film. The present invention relates to a back sheet for a solar cell module.

  A solar cell is a power generator that directly converts sunlight into electrical energy. Solar cells are broadly classified into those using silicon semiconductors and those using compound semiconductors. Silicon semiconductor solar cells include single crystal silicon solar cells, polycrystalline silicon solar cells, and amorphous silicon solar cells.

  A compound semiconductor is a semiconductor formed by combining a plurality of elements. The compound semiconductor battery includes a solar battery using a group III-V compound semiconductor (for example, GaAs) made of a combination of a group III element such as Al, Ga and In and a group V element such as As and Sb, Zn and Cd. There is a solar cell using a II-VI group compound semiconductor (for example, CdS, CdTe) composed of a combination of a group II element such as S and Se, and a group VI element such as Te. In addition, copper indium selenide solar cells, dye-sensitized solar cells, organic thin-film solar cells, and the like are being developed.

  A typical module of a solar cell includes a surface protective material, a sealing material, a solar battery cell, a back surface protective material (hereinafter also referred to as “back sheet”), and a frame. As shown in FIG. 1, main components of the solar cell module 71 include a surface protective material 72, a sealing material 73, solar cells 74, and a back surface protective material 76. A plurality of solar cells 74 are connected in series by wiring 75 to constitute a solar cell module. A frame (not shown) is disposed at the end or peripheral edge of the solar cell module.

  As the surface protection material 72, for example, a tempered glass plate, a transparent plastic plate, or a transparent plastic film is used. As the sealing material 73, an ethylene-vinyl acetate copolymer is widely used. As the back surface protective material 76, for example, a single-layer or multilayer plastic film, a plastic plate, a tempered glass plate, or a metal plate (aluminum plate, painted steel plate, etc.) is used. As the frame, for example, aluminum that is lightweight and excellent in environmental resistance is widely used.

  The structure of the solar battery cell 74 differs depending on the type of solar battery. For example, a silicon semiconductor solar cell typically has a structure in which n-type silicon and p-type silicon are joined and electrodes are arranged on each. As another solar battery cell, for example, there is one having a layer configuration of “collecting electrode / transparent conductive layer / semiconductor photoactive layer / reflective layer / conductive substrate”. The semiconductor photoactive layer is, for example, an amorphous silicon semiconductor. A solar cell module is formed by connecting a plurality of solar cells in a package using a surface protective material, a sealing material, and a back surface protective material. What connected several solar cell modules is called a solar cell array.

  The solar cell module (including the array) is generally installed outdoors, and thereafter, the operation state is maintained for a long time. In order for the solar cell module to operate satisfactorily outdoors over a long period of time, it is necessary to have excellent durability in a harsh environment. For this reason, the surface protection material, the sealing material, and the back surface protection material of the solar cell module are required to have a function of protecting the solar cells over a long period of time in a harsh natural environment surrounding the solar cell module. ing.

  The back sheet for the solar cell module is directly exposed to the outdoors on the surface (outermost surface) opposite to the solar cell, while the surface on the solar cell side (adjacent surface to the sealing material) is the surface of each solar cell. It is exposed to sunlight in the gaps and gaps between the solar cell modules. For this reason, the solar cell backsheet has light resistance, weather resistance, heat resistance, moisture resistance, water vapor barrier properties, electrical insulation, voltage resistance, mechanical properties, chemical resistance, salt resistance, antifouling properties, It is required to be excellent in various properties such as adhesiveness with a sealing material.

  As a back sheet for a solar cell module, a single layer or multilayer plastic film, a plastic plate, a tempered glass plate, a metal plate, a composite of a plastic film and a metal plate, a composite of a plastic film and a metal foil, or the like is generally used. It has been. As the metal plate, one having a synthetic resin coating film formed on the surface thereof is also used.

  From the viewpoint of satisfying various properties such as light resistance, weather resistance, heat resistance, and antifouling properties required for the solar cell module back sheet, the plastic film includes a fluororesin film, a polyethylene terephthalate (PET) film, and these. These composite films are preferably used.

  As an example of using a fluororesin film, Japanese Patent Application Laid-Open No. 2008-181929 (Patent Document 1) discloses an ethylene / tetrafluoroethylene copolymer (ETFE) resin, tetrafluoroethylene (TFE) / hexa as an outer resin layer. Fluoropropylene (HFP) / vinylidene fluoride (VDF) terpolymer resin, polyvinyl fluoride (PVF) resin, polyvinylidene fluoride (PVDF) resin, polychlorotrifluoroethylene (PCTFE) resin, tetrafluoroethylene A back surface protection sheet for a solar cell comprising a perfluoroalkyl vinyl ether copolymer resin or the like is disclosed. Japanese Patent Application Laid-Open No. 2008-211034 (Patent Document 2) discloses a back surface protection sheet for a solar cell that includes a film containing polyvinylidene fluoride and polymethyl methacrylate as an outermost layer.

  In addition to being excellent in the above characteristics, the solar cell module backsheet has a beautiful appearance on the surface of the solar battery cell, and also efficiently reflects sunlight incident on the backsheet. It is required to have a function to If the incident light transmitted through the gaps between the solar cells can be efficiently reflected by the back sheet, the power conversion efficiency of the solar cells is improved by the reflected light.

  For this reason, the coloring backsheet for solar cell modules formed by mix | blending a coloring agent with this backsheet is known.

  As a colorant, a white resin film in which an inorganic white pigment is blended with a thermoplastic resin in order to increase the reflectance of sunlight and increase the power generation efficiency of a solar cell is known. In Patent Document 3) and Japanese Patent Application Laid-Open No. 2007-208179 (Patent Document 4), titanium oxide is particularly excellent in color tone and hiding power (light scattering) among inorganic white pigments, and the color tone of a white resin film It is disclosed that it contributes to improvement of reflection characteristics.

  On the other hand, when the solar cell is arranged on the roof of a house, it is preferred to be colored in a dark color such as black from the viewpoint of appearance, and for this reason, it is colored in a dark color. There is a need for an improved solar cell backsheet.

  As a back sheet for a solar cell colored in a dark color, a sheet using carbon black, which is a black pigment, is generally used. However, carbon black absorbs sunlight and the temperature rises. As a result, not only the power generation efficiency of the battery but also the durability could decrease. Therefore, as a back sheet for a solar cell colored in a dark color, Japanese Patent Application Laid-Open No. 2007-103813 (Patent Document 5) and Japanese Patent Application Laid-Open No. 2007-197570 (Patent Document 6) are inorganic materials having infrared reflection characteristics. It is disclosed that a pigment or an infrared reflective black pigment is blended.

  If a colored resin film made of a PVDF resin composition in which a polyvinylidene fluoride (hereinafter referred to as “PVDF”) resin contains a colorant is used as a back sheet for a solar cell module, the appearance can be made beautiful. In addition, it is expected to contribute to the improvement of power conversion efficiency of solar cells.

  However, according to the research results of the present inventors, it has been found that when these colorants are contained in the PVDF resin, the thermal decomposition temperature of the PVDF resin may be significantly lowered. PVDF resin has a melting point of 177 ° C. and a thermal decomposition starting temperature of 350 ° C. When heated to a temperature of 350 ° C. or higher, it generates hydrogen fluoride (HF) gas and decomposes. These melting points and thermal decomposition starting temperatures are both typical values of PVDF resin. A wide range from the melting point to the thermal decomposition start temperature indicates that the processing temperature range of the PVDF resin is wide.

  In order to form a colored resin film from PVDF resin, it is necessary to blend a relatively large amount of colorant with PVDF resin. When a colored resin film (including a sheet) is extruded using a PVDF resin composition containing a relatively large amount of colorant in PVDF resin, the resulting colored resin film is discolored or the PVDF resin is thermally decomposed. May be easier.

  For example, among inorganic white pigments, a PVDF resin composition containing titanium oxide, which is particularly excellent in color tone and hiding power (light scattering), in PVDF resin is a hiding material suitable for solar cell module backsheets. When the thermogravimetric analysis method (TGA) is used for thermogravimetry (TGA), the 10% thermogravimetric temperature decrease is about 40 ° C. to about 55 ° C. C may also decrease. The 10% thermal weight loss temperature of PVDF resin alone is typically in the range of about 380 ° C to about 385 ° C. On the other hand, for example, the 10% thermal weight reduction temperature of the PVDF resin composition containing 100 parts by weight of the PVDF resin and 10 parts by weight of titanium oxide as a white pigment decreases to about 330 ° C.

  In addition, a film formed from a PVDF resin composition containing PVDF resin and titanium oxide turns brown after several hours when subjected to a heat resistance test in a gear oven heated to a temperature of 230 to 270 ° C. As a result, foaming, which is presumed to be a trace of the generation of cracked gas, may be observed. Even if polymethylmethacrylate compatible with the PVDF resin is contained in the resin composition containing the PVDF resin and titanium oxide, the heat resistance reduction and thermal discoloration caused by the titanium oxide cannot be improved. Such a defect cannot be eliminated even if a method of forming a coating film using the PVDF resin composition as a coating liquid is employed.

  In addition, in a film formed from a PVDF resin composition containing a PVDF resin and a black pigment, carbon black, as a solar cell backsheet colored in a dark color, the carbon black absorbs sunlight. As a result, the temperature rises, and not only the power generation efficiency of the solar cell decreases, but also the durability may decrease.

  As described above, the film formed from the PVDF resin composition has excellent characteristics suitable for a back sheet for a solar cell module. However, when a colorant is contained, the heat resistance and the appearance are remarkably deteriorated. , The durability may be inferior. For this reason, the heat resistance of the PVDF resin is further improved to obtain a PVDF resin composition more suitable for the solar cell module backsheet, and at the same time, in a film formed from a PVDF resin composition containing a colorant in the PVDF resin. As a result, a remarkable reduction in heat resistance and appearance can be suppressed. As a result, the appearance of the solar cell module can be made beautiful, the power conversion efficiency of the solar cell can be increased, and a colored resin film excellent in durability can be obtained. It was strongly desired to get.

JP 2008-181929 A JP 2008-211034 A Japanese Patent Laid-Open No. 2002-100788 JP 2007-208179 A JP 2007-103813 A JP 2007-197570 A

  An object of the present invention is to provide a PVDF resin composition that improves the heat resistance of the PVDF resin and suppresses thermal decomposition and thermal discoloration even when the PVDF resin contains a large amount of colorant. There is to do.

  Another object of the present invention is to use a resin composition containing a large amount of a colorant in a PVDF resin, so that thermal decomposition and thermal discoloration during molding can be suppressed. An object of the present invention is to provide a colored resin film that is remarkably suppressed and excellent in appearance, hiding power (light scattering property), and durability.

  Still another object of the present invention is to provide a highly durable back sheet having various properties suitable for a back sheet for a solar cell module, using a PVDF resin composition containing a PVDF resin and a colorant. There is to do.

  As a result of intensive studies to solve the above problems, the present inventors surprisingly added the talc known as a filler to the PVDF resin, and unexpectedly, the compound acts as a heat stabilizer, As a result, it has been found that the heat resistance of the PVDF resin is improved, and even when the PVDF resin contains a large amount of colorant, PVDF that can sufficiently suppress thermal decomposition and thermal discoloration over time during molding or over time. It has been found that a resin composition can be obtained.

  Resin films formed from the PVDF resin composition of the present invention, particularly colored resin films (including sheets) containing a colorant, are remarkably suppressed in thermal decomposition and thermal discoloration, and have an appearance and a hiding power (light scattering). Property), heat resistance, and durability, and various properties suitable for a solar cell module backsheet. The present invention has been completed based on these findings.

  According to the present invention, there is provided a PVDF resin composition containing 0.5 to 70 parts by weight of talc as a heat stabilizer with respect to 100 parts by weight of PVDF resin. As an embodiment thereof, the PVDF resin composition containing 0.8 to 50 parts by weight of the talc is provided.

Moreover, according to the present invention, as a particularly preferred embodiment, the PVDF resin composition further containing a colorant, that is, a PVDF resin composition containing talc as a PVDF resin, a colorant, and a heat stabilizer, ,
(A) The content of the colorant is 2 to 60 parts by weight with respect to 100 parts by weight of the PVDF resin,
(B) The content ratio of talc is 2 to 60 parts by weight with respect to 100 parts by weight of the PVDF resin, and
(C) The PVDF resin composition is provided in which the weight ratio of the colorant to talc is 20: 1 to 1:20.

Furthermore, as embodiments of these, the following PVDF resin compositions (1) to (7) are provided.
(1) The PVDF resin composition, wherein the PVDF resin is at least one selected from the group consisting of a vinylidene fluoride homopolymer and a vinylidene fluoride copolymer.
(2) Vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-tetrafluoroethylene copolymer, wherein the vinylidene fluoride copolymer has a copolymerization ratio with vinylidene fluoride units of 15 mol% or less. , Vinylidene fluoride-chlorotrifluoroethylene copolymer, vinylidene fluoride-trifluoroethylene copolymer, vinylidene fluoride-tetrafluoroethylene-hexafluoropropylene terpolymer, and vinylidene fluoride-chlorotrifluoroethylene -The said PVDF resin composition which is at least 1 type of vinylidene fluoride copolymer chosen from the group which consists of a hexafluoropropylene terpolymer.
(3) The PVDF resin composition described above, wherein the talc has an average particle size (D ₅₀ ) of 0.5 to 20 μm and an apparent density of 0.05 to 0.5 g / cm ³ .
(4) The said PVDF resin composition which further contains another thermoplastic resin in the ratio of 30 weight part or less with respect to 100 weight part of PVDF resin.
(5) The PVDF resin composition described above, wherein the other thermoplastic resin is polymethyl methacrylate.
(6) The PVDF resin composition as described above, wherein the colorant is at least one selected from the group consisting of titanium oxide and carbon black.
(7) PVDF resin 100 is used as another additive that is at least one selected from the group consisting of pigment dispersants, ultraviolet absorbers, light stabilizers, matting agents, lubricants, color modifiers, crystal nucleating agents, and elastomers. The said PVDF resin composition which further contains in the ratio of 10 weight part or less each independently with respect to a weight part.

Furthermore, according to the present invention, a colored resin film formed from the PVDF resin composition containing the colorant, that is, a PVDF resin, a colorant, and a PVDF resin composition containing talc as a heat stabilizer. A colored resin film formed,
(A) The content of the colorant is 2 to 60 parts by weight with respect to 100 parts by weight of the PVDF resin,
(B) The content ratio of talc is 2 to 60 parts by weight with respect to 100 parts by weight of the PVDF resin, and
(C) A colored resin film formed from a PVDF resin composition having a weight ratio of the colorant to talc of 20: 1 to 1:20 is provided.

  And according to this invention, the solar cell module backsheet containing the layer which consists of this coloring resin film is provided.

  The present invention can improve the heat resistance of the PVDF resin, and the PVDF resin composition containing a large amount of colorant in the PVDF resin can suppress thermal decomposition and thermal discoloration during molding. There is an effect. Further, the colored resin film comprising the PVDF resin composition containing a large amount of the colorant in the PVDF resin according to the present invention is inhibited from thermal decomposition and thermal discoloration during molding, and further, thermal decomposition and thermal discoloration with time are suppressed. It is remarkably suppressed and has the effect of being excellent in appearance, hiding power (light scattering property), heat resistance, and durability. Furthermore, in the present invention, the back sheet for a solar cell module including the layer made of the colored resin film is remarkably suppressed in thermal decomposition and thermal discoloration over time, and has an appearance, hiding power (light scattering property), heat resistance, And the effect that it is excellent in durability is produced.

FIG. 1 is a schematic cross-sectional view of an example of a solar cell module.

1. Polyvinylidene fluoride resin The polyvinylidene fluoride resin (PVDF resin) used in the present invention means a homopolymer of vinylidene fluoride and a vinylidene fluoride copolymer mainly composed of vinylidene fluoride. PVDF resin used in the present invention, alpha-type, beta-type, gamma-type, a crystalline resin exhibiting a different crystal structure, such as alpha _p-type. The PVDF resin used in the present invention is not an elastomer (fluoro rubber) that has lost its crystallinity.

  Examples of the vinylidene fluoride copolymer include a vinylidene fluoride-hexafluoropropylene copolymer, a vinylidene fluoride-tetrafluoroethylene copolymer, a vinylidene fluoride-chlorotrifluoroethylene copolymer, and a vinylidene fluoride-tri A fluoroethylene copolymer, a vinylidene fluoride-tetrafluoroethylene-hexafluoropropylene terpolymer, a vinylidene fluoride-chlorotrifluoroethylene-hexafluoropropylene terpolymer, and a mixture of two or more thereof. Can be mentioned.

  These vinylidene fluoride copolymers have a copolymerization ratio with vinylidene fluoride units, that is, a comonomer copolymerization ratio of usually 15 mol% or less, preferably 10 mol% or less, more preferably 5 mol%. It is as follows. When the copolymerization ratio of the comonomer is 15 mol% or less, the vinylidene fluoride copolymer becomes a thermoplastic resin having crystallinity. The lower limit of the comonomer copolymerization ratio is preferably 1 mol%. If the copolymerization ratio of the comonomer becomes too high, the vinylidene fluoride copolymer loses crystallinity and becomes an elastomer.

  Therefore, as the PVDF resin, at least one selected from the group consisting of a vinylidene fluoride homopolymer and a vinylidene fluoride copolymer having a comonomer copolymerization ratio of 15 mol% or less can be used. Among PVDF resins, vinylidene fluoride homopolymers and vinylidene fluoride-hexafluoropropylene copolymers having a copolymerization ratio of hexafluoropropylene units of 15 mol% or less are heat resistant, melt moldable, mechanical From the viewpoints of properties, antifouling properties, solvent resistance, secondary workability, etc., it is particularly preferable.

  PVDF resin can generally be produced by a suspension polymerization method or an emulsion polymerization method. In the emulsion polymerization method, a chemically stable fluorine-based emulsifier is used to emulsify vinylidene fluoride alone or vinylidene fluoride and a comonomer such as hexafluoropropylene in an aqueous medium. Subsequently, it superposes | polymerizes using an inorganic peroxide, an organic peroxide, an organic percarbonate compound etc. as a polymerization initiator. After emulsion polymerization, a fine latex of submicron units is precipitated with a flocculant and agglomerated to collect PVDF resin as particles of an appropriate size.

  In the suspension polymerization method, a vinylidene fluoride or the vinylidene fluoride and a comonomer are suspended in an aqueous medium using a suspending agent such as methylcellulose. For example, an organic percarbonate (for example, di-n-propyl peroxydicarbonate) exhibiting activity at a low temperature is used as a polymerization initiator, and the temperature of vinylidene fluoride is 30.1 ° C. or less, preferably 10-30. Polymerization is started at 20 ° C., more preferably 20-28 ° C. to produce primary polymer particles, and if necessary, the temperature is raised to 30-90 ° C., preferably 40-80 ° C., and the polymerization reaction is continued. To produce secondary polymer particles.

  The intrinsic viscosity of the PVDF resin is preferably 0.7 to 1.5 dl / g, more preferably 0.8 to 1.3 dl / g. The intrinsic viscosity of the PVDF resin is a logarithmic viscosity at 30 ° C. measured using a Ubbelohde viscometer for a solution obtained by dissolving 4 g of PVDF resin in 1 liter of N, N-dimethylformamide.

  The melting point of PVDF resin is usually in the range of 130 to 185 ° C, and in many cases 150 to 180 ° C. The melting point of PVDF resin is a value measured by a differential scanning calorimeter (DSC). When PVDF resin is heated to a temperature of 350 ° C. or higher, it generates HF gas and starts to decompose. PVDF resin has a wide processable temperature range from the melting point to the decomposition point. The melt processing temperature of PVDF resin is usually in the range of 200 to 250 ° C. The heat resistance of the PVDF resin can be evaluated by a 10% thermal weight loss temperature described in detail later. In addition, when the PVDF resin is a vinylidene fluoride homopolymer, the 10% thermal weight loss temperature is usually about 380 ° C.

2. Talc which is a heat stabilizer The talc used as a heat stabilizer in the present invention is a powdered material obtained by pulverizing talc which is a kind of clay mineral, and its chemical composition is a composition comprising magnesium hydroxide and silicate. It is a hydrous magnesium silicate represented by the formula Mg ₃ Si ₄ O ₁₀ (OH) ₂ .

Various types of talc are known. If classified by average particle size, general-purpose talc that is about 10 to 20 μm, fine-particle talc that is about 10 to 10 μm, ultrafine-particle talc that is about 1 μm or less, about 20 μm or more There is a high bulk density talc. The talc used as a heat stabilizer in the present invention may cause dispersion failure due to aggregation if the particle size is too small, and may decrease fluidity, and if the particle size is too large, it may cause deterioration of mechanical properties or appearance failure. Therefore, the average particle size is preferably in the range of 0.5 to 20 μm, more preferably 1 to 18 μm, and particularly preferably 2 to 16 μm. The average particle diameter means a number average particle diameter (D ₅₀ ) calculated as an integrated value of 50% of the primary particle diameter measured by the laser diffraction method. For example, a particle diameter measuring instrument SALD manufactured by Shimadzu Corporation It can be measured using -3000J. The sharper the particle size distribution of talc is, the more preferable, and it is particularly preferable to use talc from which particles having a particle size exceeding 20 μm are removed as much as possible.

The apparent density of talc used in the present invention measured by JIS K5101 is preferably 0.05 to 0.5 g / cm ³ , more preferably 0.08 to 0.45 g / cm ³ , and particularly preferably 0.1 to 0.1 g / cm ³ . The range is 0.4 g / cm ³ . The specific surface area according to the BET method of talc used in the present invention is preferably in the range of ³ to 25 m ² / g, more preferably 3.5 to ²⁰ m ² / g, and particularly preferably 4 to 16 m ² / g. Moreover, the oil absorption amount measured by JIS K5101 of the talc used by this invention becomes like this. Preferably it is 15-60 ml / 100g, More preferably, it is 18-55 ml / 100g, Most preferably, it is the range of 20-50 ml / 100g. The talc used in the present invention is preferably one having as few impurities as possible such as iron oxide and aluminum oxide, and calcined talc, talc from which impurities have been removed by washing with an acid such as hydrochloric acid or sulfuric acid, etc. can be preferably used. . Furthermore, talc that has been subjected to surface hydrophobic treatment with a silane coupling agent, a titanate coupling agent, or the like can also be used. The talc used in the present invention may or may not be subjected to aminosilane treatment. However, in order to balance mechanical properties and heat resistance, it is preferable not to perform aminosilane treatment.

  SG-95 having an average particle diameter of 2.5 μm (Japan) is used as a talc as a heat stabilizer from the viewpoint of excellent effect of suppressing coloring and thermal decomposition of PVDF resin and good dispersibility in PVDF resin. Talc Co., Ltd.) and MS (Nihon Talc Co., Ltd.) having an average particle size of 14 μm are preferably used. The talc which is a heat stabilizer can be used individually by 1 type or in combination of 2 or more types.

  The production method when grinding talc from raw stones is not particularly limited, but the apparent density of talc is increased by granulating talc degassed and compressed, or a small amount of clay-like material such as montmorillonite as a binder. Is preferable because it is excellent in productivity and dispersibility in producing the composition.

3. Colorant The colorant used in the present invention is not particularly limited as long as it does not impair the color tone and hiding power (light scattering property) of the PVDF resin, but the color tone and hiding power (light scattering property) are not limited. Since it is particularly excellent, inorganic white pigments such as titanium oxide, inorganic pigments having reflection characteristics, black pigments such as carbon black, and the like can be preferably used.

(1) Inorganic white pigment As the inorganic white pigment, ZnO, TiO ₂ , Al ₂ O ₃ .nH ₂ O, [ZnS + BaSO ₄ ], CaSO ₄ .2H ₂ O, BaSO ₄ , CaCO ₃ , 2PbCO ₃ .Pb (OH ) ₂ etc. are mentioned. Among inorganic white pigments, color tone and hiding power (light scattering property) are particularly excellent, and titanium oxide (TiO ₂ ) is preferable because it can contribute to improvement in color tone and reflection characteristics of the white resin film.

  Titanium oxide is widely used in two crystal forms, anatase and rutile. In the present invention, these two types of crystal forms can be used, but among these, since they are excellent in dispersibility in PVDF resin at high temperatures and have extremely low volatility, they have a rutile type crystal form. Titanium oxide is preferred.

As the titanium oxide, pigment grades can be preferably used. The average particle diameter (average primary particle diameter) of titanium oxide by image analysis of a transmission electron microscope image is usually 150 to 1000 nm, preferably 200 to 700 nm, and more preferably 200 to 400 nm. When the average particle diameter of titanium oxide is too small, the hiding power is reduced. Since the average particle diameter of titanium oxide is within the above range, the refractive index is large and the light scattering property is strong, so that the hiding power as a white pigment is increased. Titanium oxide is generally present in the form of secondary particles in which primary particles are aggregated. The specific surface area of titanium oxide by the BET method is usually in the range of ^{1 to} 15 m ² / g, and in many cases 5 to 15 m ² / g.

  Titanium oxide can improve properties such as dispersibility, concealability, and weather resistance by surface treatment with a surface treatment agent. Examples of the surface treating agent include metal oxides such as aluminum, silicon, zirconium, tin, cerium, and bismuth; hydrated metal oxides such as zinc oxide; organometallic compounds such as organoaluminum compounds, organotitanium compounds, and organozirconium compounds; Examples thereof include organosilicon compounds such as silane coupling agents and polysiloxanes; phosphorus compounds such as aluminum phosphates and organophosphates; amine compounds.

(2) Black pigment As the black pigment, an inorganic pigment having infrared reflection characteristics can be used. The pigment has a property of preventing heat storage by reflecting infrared rays of a specific wavelength even if it is colored black or chromatic in appearance, and has low heat deformation and excellent heat resistance. Even if it is used outdoors for a long time, it does not easily hydrolyze and has excellent weather resistance. Therefore, if it is contained in a resin composition that forms a colored resin film used for a solar cell backsheet, the power generation efficiency of the solar cell decreases. It is possible to prevent the durability from being deteriorated, and thermal decomposition or discoloration during molding. As an inorganic pigment having infrared reflection characteristics, an oxide containing at least two elements selected from Fe, Cr and Mn disclosed in the above-mentioned Patent Document 5 or 6, for example, Fe (Fe, Cr) ₂ O ₄ , (Co, Fe) (Fe, Cr) ₂ O ₄ , Cu (Cr, Mn) ₂ O ₄ , (Cu, Fe, Mn) (Fe, Cr, Mn) ₂ O ₄ , (Fe, Zn) ( Fe, Cr) ₂ O ₄ , Cr ₂ O ₃ : Fe ₂ O ₃ , oxides containing Co and Ni elements, specifically (Ni, Co, Fe) (Fe, Cr) ₂ O _4, etc. And a composite oxide containing Fe, Co, and Al, and further containing one or more metals selected from Mg, Ca, Sr, Ba, Ti, Zn, Sn, Zr, Si, and Cu.

Moreover, as a black pigment, carbon black is preferable. Usually, it is not particularly limited as long as it is a carbon black used for a solar battery backsheet or the like, and furnace black, channel black, acetylene black, thermal black, etc. can be used, and the surface is modified by a carboxyl group or the like. Carbon black can also be used. The average particle diameter (average primary particle diameter) of carbon black by image analysis of transmission electron microscope images is usually in the range of 10 to 150 nm, preferably 13 to 100 nm, and more preferably 15 to 40 nm. If the average particle size of the carbon black is too small, the carbon black is likely to aggregate and be difficult to handle. If the average particle size is too large, there is a risk of causing poor dispersion and poor appearance. The specific surface area of the carbon black by the BET method is usually 20 to 250 m ² / g, preferably 50 to ²⁰⁰ m ² / g, more preferably 80 to ²⁰⁰ m ² / g.

4). PVDF resin composition As for the PVDF resin composition of this invention, the content rate of the talc which is a heat stabilizer is in the range of 0.5-70 weight part with respect to 100 weight part of PVDF resin. The content ratio of talc as a heat stabilizer is preferably in the range of 0.6 to 65 parts by weight, more preferably 0.7 to 60 parts by weight, and particularly preferably 0.8 to 55 parts by weight. The content ratio of talc, which is a heat stabilizer when not using a colorant, is preferably in the range of 0.7 to 55 parts by weight, more preferably 0.8 to 50 parts by weight, and particularly preferably 0.9. Within the range of ~ 45 parts by weight. The content ratio of talc, which is a heat stabilizer in the case of using a colorant in combination, is preferably in the range of 2 to 60 parts by weight, more preferably 5 to 55 parts by weight, still more preferably 6 to 50 parts by weight, particularly Preferably it exists in the range of 7-45 weight part. When the content ratio of the heat stabilizer is too small, the heat stabilization effect is reduced, and it is difficult to sufficiently suppress the decrease in the thermal decomposition temperature of the PVDF resin component in the PVDF resin composition. When the content ratio of the heat stabilizer is too large, the hiding power, color tone, mechanical properties, etc. of the resin film may be adversely affected.

  The content ratio of the colorant in the PVDF resin composition of the present invention is usually in the range of 2 to 60 parts by weight, preferably 4 to 55 parts by weight, more preferably 6 to 50 parts per 100 parts by weight of the PVDF resin. Part by weight, particularly preferably in the range of 8 to 45 parts by weight. When the content rate of a coloring agent is too small, it will become difficult to obtain the colored resin film which has the color tone and hiding power which can be utilized as a solar cell module backsheet. When the content ratio of the colorant is too large, it becomes difficult to produce a colored resin film by extrusion, and the mechanical strength of the colored resin film is lowered.

  In order to efficiently enhance the heat stabilization effect by the heat stabilizer talc, it is preferable to adjust the content ratio of the talc as the heat stabilizer according to the content ratio of the colorant in the PVDF resin composition. The content ratio of talc, which is a heat stabilizer, may be larger or smaller than the content ratio of the colorant. The weight ratio of the colorant to the heat stabilizer is preferably in the range of 20: 1 to 1:20, more preferably 15: 1 to 1:15, even more preferably 12: 1 to 1:12, especially Preferably it is in the range of 10: 1 to 1:10, most preferably 5: 1 to 1: 5.

  The PVDF resin composition of the present invention can contain other thermoplastic resins such as polymethyl methacrylate compatible with the PVDF resin. The other thermoplastic resin is preferably used in a proportion of 30 parts by weight or less, more preferably 25 parts by weight or less, with respect to 100 parts by weight of the PVDF resin. When other thermoplastic resins are used, the lower limit is usually 0.01 parts by weight, preferably 0.1 parts by weight, more preferably 1 part by weight. Among other thermoplastic resins, polymethyl methacrylate (PMMA) not only has excellent compatibility with PVDF resin, but also improves adhesion to other members of the colored resin film formed from the PVDF resin composition. Particularly preferred.

  In the PVDF resin composition of the present invention, a pigment dispersant, an ultraviolet absorber, a light stabilizer, a matting agent, a lubricant, a color adjusting agent, a crystal nucleating agent, a mechanical property improving agent (for example, an acrylic elastomer) Other additives selected from elastomers and the like can be contained. These additives are optionally used in proportions suitable for each, and are preferably 10 parts by weight or less, more preferably 5 parts by weight or less, particularly preferably 100 parts by weight of PVDF resin. It is used at a ratio of 3 parts by weight or less. When these additives are used, the lower limit of the content is usually 0.001 parts by weight, and in many cases 0.01 parts by weight, independently of 100 parts by weight of the PVDF resin.

  The PVDF resin composition can be prepared by a method of dry blending a PVDF resin, talc as a heat stabilizer, and, if necessary, a colorant. PVDF resin powder or pellets, together with talc, which is a heat stabilizer, and, if necessary, a colorant, can be supplied to an extruder, melt-kneaded, melt-extruded into a strand, cut and pelletized . When other additives and / or other thermoplastic resins are used, they are contained in the blending step or the pellet step.

  When the PVDF resin composition is used as a powder coating material, the PVDF resin composition is prepared by a method of dry blending PVDF resin powder, talc as a heat stabilizer, and, if necessary, a colorant. When other additives and / or other thermoplastic resins are used, they are contained in the blending step. Such a dry blend can be used not only as a powder coating material but also supplied to an extruder and melt-extruded as a film (including a sheet).

  The PVDF resin composition can be in the form of an organosol coating if desired. The organosol paint is prepared by a conventional method using PVDF resin powder, talc as a heat stabilizer, and, if necessary, a colorant, an acrylic resin (film forming aid) and an organic solvent, and optionally other additives and It can be prepared by a method of dispersing other thermoplastic resins using a roll mill, a sand grinder or the like. PVDF resin composition can also be made into the form of a dispersion paint by a conventional method.

  When thermogravimetric analysis (TGA) is used for the PVDF resin composition of the present invention, the 10% thermogravimetric decrease temperature is usually 340 ° C or higher, preferably 360 ° C or higher, more preferably 370 ° C. As described above, particularly preferably, 380 ° C. or higher can be exhibited. Especially, when the PVDF resin composition of the present invention does not contain a colorant, it is preferably 390 ° C. or higher, more preferably 400 ° C. or higher, further preferably 410 ° C. or higher, particularly preferably 425 ° C. or higher, Most preferably, it can show 440 degreeC or more.

  When the PVDF resin composition of the present invention is a PVDF resin composition containing a colorant, the PVDF resin composition does not contain a heat stabilizer, although it may vary depending on the type of the colorant. The degree of increase in the 10% thermal weight loss temperature is usually 5 ° C. or higher, preferably 10 ° C. or higher, more preferably 15 ° C. or higher, more preferably 25 ° C. or higher, particularly preferably 40 ° C. or higher. Preferably 60 degreeC or more is shown. As a result, the PVDF resin composition containing the colorant of the present invention can be expected to have heat resistance that can be handled in substantially the same manner as in the case of the PVDF resin alone. In addition, the 10% thermogravimetric decrease temperature of the PVDF resin composition of the present invention, when the PVDF resin composition does not contain a colorant, the degree of increase of the 10% thermogravimetric decrease temperature compared to the PVDF resin alone, Usually, it may be 10 ° C or higher, preferably 20 ° C or higher, more preferably 30 ° C or higher, still more preferably 40 ° C or higher, and particularly preferably 50 ° C or higher.

  Since the PVDF resin composition of the present invention is excellent in heat resistance, for example, when it is molded into a film or sheet and subjected to a heat test, it is thermally discolored, surface properties are deteriorated, and mechanical strength is reduced. There is nothing to do.

5. Colored resin film A PVDF resin composition containing a colorant can be formed into a colored resin film by supplying it to an extruder and melt-extruding it into a film form from a T-die placed at the tip of the extruder. . In the present invention, the resin film includes not only a film having a thickness of less than 250 μm but also a sheet (including a plate) having a thickness of 250 μm to 3 mm.

  The lower limit of the thickness of the colored resin film is usually 5 μm, preferably 10 μm, more preferably 20 μm, and particularly preferably 30 μm. The upper limit of the thickness of the colored resin film is preferably 500 μm, more preferably 300 μm, still more preferably 200 μm, and particularly preferably 150 μm. If the thickness of the colored resin film is too thin, it will be difficult to obtain a sufficient color tone and hiding power, and the mechanical properties will also deteriorate. If the thickness of the colored resin film is too thick, flexibility may be impaired or it may be difficult to reduce the weight. The thickness of the colored resin film can exhibit good characteristics particularly in the range of 40 to 120 μm.

  When the PVDF resin composition of the present invention is used in the form of a powder paint, an organosol paint or a dispersion paint, it is coated on a heat-resistant substrate such as a metal plate, a glass plate or a heat-resistant resin film and heated. It can be formed into a film by the method to do.

6). Solar cell module and back sheet for solar cell module Examples of the solar cell module on which the back sheet for solar cell module of the present invention can be disposed include those having a cross-sectional structure shown in FIG. As shown in FIG. 1, the solar cell module includes a surface protection material 72, a sealing material 73, solar cells 74, and a back surface protection material 76. A plurality of solar cells 74 are connected in series by wiring 75 to constitute a solar cell module. A frame (not shown) is disposed at the end or peripheral edge of the solar cell module.

  Examples of the surface protective material 72 include, but are not limited to, a tempered glass plate, a transparent plastic plate, a single-layer or multilayer transparent plastic film, and a composite material obtained by combining these. As the sealing material 73, a transparent resin such as an ethylene-vinyl acetate copolymer (EVA), a butyral resin, a silicon resin, an epoxy resin, or a fluorinated polyimide resin is used, but is not limited thereto. Among these sealing materials, EVA is preferable. The structure of the solar battery cell 74 varies depending on the type of the solar battery, but various solar battery cells can be used.

  In the present invention, as the back surface protective material (back sheet) 76, a single-layer colored resin film comprising the PVDF resin composition of the present invention, and the colored resin film and another resin film (for example, PET film) are combined. A multilayer film obtained by combining the colored resin film and a moisture-proof film, a composite material obtained by combining the colored resin film and a tempered glass plate, a composite material obtained by combining the colored resin film and a metal plate, The composite material etc. which compounded 2 or more types, such as this colored resin film, another resin film, a moisture-proof film, a tempered glass board, etc. are used. Multilayer films and composite materials can have an adhesive layer between each layer. Examples of the moisture-proof film include a composite film in which a deposited film of an inorganic oxide such as silicon oxide or aluminum oxide is formed on one surface of a base film. Examples of the commercially available moisture-proof film include CELLEL (registered trademark) T030 manufactured by Kureha Corporation.

  When using EVA as a sealing material, EVA is normally supplied as a sheet. The solar battery cell can be sealed with EVA by sandwiching the solar battery cell between two EVA sheets and pressurizing and heating. The EVA sheet can be supplied in combination with a colored resin film made of a PVDF resin composition.

  Examples of the preferable layer configuration of the solar cell module backsheet of the present invention include the following, but are not limited thereto. The back sheet having a multi-layer structure shows the surface on the side in contact with the solar cell module as the right end.

1) Colored resin film 2) Colored resin film / adhesive / EVA
3) Other resin film / colored resin film 4) Other resin film / adhesive / colored resin film 5) Other resin film / colored resin film / adhesive / EVA
6) Other resin film / adhesive / colored resin film / adhesive / EVA
7) Glass plate / adhesive / colored resin film 8) Glass plate / adhesive / colored resin film / adhesive / EVA
9) Metal plate / adhesive / colored resin film 10) Metal plate / adhesive / colored resin film / adhesive / EVA
11) Layer structure obtained by adding a moisture-proof film to the above layer structure

  When the back sheet for a solar cell module of the present invention is a multilayer sheet containing a colored resin film, the colored resin film is adjacent to the sealing material (for example, EVA) layer directly or via an adhesive layer.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated more concretely, this invention is not limited to these Examples. Moreover, the measuring method of 10% thermogravimetric reduction temperature is as follows.

(Measurement of 10% thermal weight loss temperature)
The 10% thermogravimetric decrease temperature was measured using a thermogravimetric analyzer TGA SDTA851 manufactured by METTLER TOLEDO Co., Ltd. 20 mg of a pellet-like sample that had been vacuum-dried at 30 ° C. for 6 hours or more was placed in a platinum pan, and dry nitrogen was 10 ml / min. The temperature was increased from 50 ° C. to 490 ° C. at a rate of temperature increase of 10 ° C./min in the atmosphere, and the weight reduction rate during that time was measured. The temperature when the sample weight decreased by 10% by weight from the sample weight at the start of measurement was defined as a 10% thermogravimetric decrease temperature.

[Reference example]
It was 382 degreeC when the 10% thermogravimetric decrease temperature of PVDF resin [KF (trademark) # 850 by Kureha Co., Ltd .; suspension polymerization product] was measured. The results are shown in Table 1.

[Example 1]
10 parts by weight of titanium oxide [TI-PURE (registered trademark) R101 manufactured by DuPont; rutile titanium oxide, average particle size of 0.29 μm, surface-treated product with amine compound] with respect to 100 parts by weight of PVDF resin of Reference Example; , 30 parts by weight of talc [SG-95 manufactured by Nippon Talc Co., Ltd., average particle size 2.5 μm, apparent density 0.11 g / cm ³ , specific surface area 15 m ² / g, oil absorption 47 ml / 100 g] And melt-kneaded at a cylinder temperature of 220 ° C., melt-extruded in a strand form from a die, and cut in cold water to produce pellets. Using this pellet, the 10% thermal weight loss temperature was measured and found to be 345 ° C. Moreover, this pellet was supplied to a single screw extruder (manufactured by Pla Giken Co., Ltd.), melt-extruded from a T die having a lip clearance of 1 mm at a resin temperature of 240 ° C., cooled with a 90 ° C. cooling roll, and a thickness of 100 μm. A resin film was prepared. Table 1 shows the measurement results of the 10% thermal weight loss temperature of the pellets.

[Comparative Example 1]
The same operation as in Example 1 was performed except that the talc was not used. Table 1 shows the measurement results of the 10% thermal weight loss temperature of the pellets.

[Example 2]
Implemented except that 10 parts by weight of titanium oxide was changed to 10 parts by weight of carbon black (Mitsubishi Chemical Co., Ltd., carbon black # 45) and the amount of talc was changed from 30 parts by weight to 10 parts by weight. The same operation as in Example 1 was performed. Table 1 shows the measurement results of the 10% thermal weight loss temperature of the pellets.

[Example 3]
The same operation as in Example 2 was performed except that 100 parts by weight of the PVDF resin of the reference example was changed to a mixture of 80 parts by weight of the PVDF resin and 20 parts by weight of polymethyl methacrylate (manufactured by Mitsubishi Rayon Co., Ltd., HBS001). went. Table 1 shows the measurement results of the 10% thermal weight loss temperature of the pellets.

[Comparative Example 2]
The same operation as in Example 2 was performed except that the talc was not used. Table 1 shows the measurement results of the 10% thermal weight loss temperature of the pellets.

[Comparative Example 3]
The same operation as in Example 3 was performed except that the talc was not used. Table 1 shows the measurement results of the 10% thermal weight loss temperature of the pellets.

[Example 4]
The same operation as in Example 1 was performed except that 1 part by weight of the talc was supplied to a single screw extruder instead of 10 parts by weight of the titanium oxide and 30 parts by weight of the talc. Table 1 shows the measurement results of the 10% thermal weight loss temperature of the pellets.

[Examples 5 to 7]
The same operation as in Example 4 was performed, except that 1 part by weight of the talc was changed to 3, 5 or 40 parts by weight of the talc. Table 1 shows the measurement results of the 10% thermal weight loss temperature of the pellets.

[Examples 8 to 10]
1 part by weight of talc having an average particle diameter of 2.5 μm was added to each talc having an average particle diameter of 14 μm [MS manufactured by Nippon Talc Co., Ltd., apparent density 0.35 g / cm ³ , specific surface area 4.5 m ² / g, oil absorption The same operation as in Example 4 was performed except that the amount was changed to 1, 3 or 5 parts by weight. Table 1 shows the measurement results of the 10% thermal weight loss temperature of the pellets.

[Comparative Example 4]
1 part by weight of talc having an average particle diameter of 2.5 μm was mixed with talc having an average particle diameter of 23 μm [MS-KY manufactured by Nippon Talc Co., Ltd., apparent density 0.55 g / cm ³ , specific surface area 2.5 m ² / g, oil absorption The same operation as in Example 4 was carried out except that the amount 21 ml / 100 g] was changed to 5 parts by weight. Table 1 shows the measurement results of the 10% thermal weight loss temperature of the pellets.

  From the results of Table 1, the resin composition (Comparative Example 1) in which 10 parts by weight of titanium oxide is blended with 100 parts by weight of PVDF resin is 10% thermal weight as compared with the case of PVDF resin alone (Reference Example 1). It was found that the decrease temperature was remarkably lowered to 52 ° C. and the heat resistance was poor. On the other hand, an example in which 30 parts by weight of talc as a heat stabilizer (colorant: stabilizer = 1: 3) was added to 10 parts by weight of titanium oxide as a colorant with respect to 100 parts by weight of PVDF resin. The resin composition of No. 1 had a 10% thermal weight reduction temperature increased by 15 ° C. compared to Comparative Example 1, and the heat resistance was improved to a 10% thermal weight reduction temperature exceeding 340 ° C. It was found that there is no heat resistance.

  Moreover, the resin composition (Comparative Example 2) containing 10 parts by weight of carbon black has a 10% thermal weight reduction temperature slightly lower than that of the PVDF resin alone (Reference Example 1), and the solar cell backsheet. It was found that the solar cell absorbs sunlight and the temperature rises, so that the power generation efficiency of the solar cell is lowered and the durability is inferior. Even when polymethyl methacrylate (PMMA) was added as a resin component (Comparative Example 3), no improvement in heat resistance was observed. On the other hand, an example in which 10 parts by weight of carbon black as a colorant and 10 parts by weight of talc as a heat stabilizer (colorant: stabilizer = 1: 1) were added to 100 parts by weight of PVDF resin. In the resin composition of No. 2, the 10% thermogravimetric temperature decrease markedly increased to 80 ° C. compared to Comparative Example 2, and the heat resistance was greatly improved, compared with the case of the PVDF resin alone of the reference example. Even at 78 ° C., the heat resistance and durability were found to be extremely excellent. Similarly, when Example 3 is compared with Comparative Example 3 in which the resin component is 80 parts by weight of PVDF resin and 20 parts by weight of PMMA, 10 parts by weight of talc, which is a thermal stabilizer (colorant: stabilizer = 1: 1). It was found that the 10% thermogravimetric temperature decrease markedly increased to 81 ° C., and the heat resistance was greatly improved.

Furthermore, 1 part by weight (Example 4), 3 parts by weight (Example 5), 5 parts by weight (Example 6) of talc, which is a heat stabilizer, without adding a colorant to 100 parts by weight of PVDF resin. Or by adding 40 parts by weight (Example 7), compared to the case of PVDF resin alone in Reference Example 1, the effect of an unexpected heat resistance improvement in which the 10% thermal weight loss temperature rises by 20 ° C. or more is obtained. I found out that it was played. In particular, in Example 7, it was found that a remarkable thermal stability effect was achieved since the temperature increased by 79 ° C. from the 10% thermogravimetric decrease temperature of the PVDF resin alone. In addition, in the resin composition of Comparative Example 4 in which 5 parts by weight of talc having an average particle diameter of 23 μm and an apparent density of 0.55 g / cm ³ was blended, the 10% thermal weight reduction temperature was 391 ° C., but in the pellet Talc particles were observed with the naked eye and found to be inferior in transparency.

  By containing talc as a thermal stabilizer, the PVDF resin composition of the present invention can increase the 10% thermogravimetric reduction temperature as compared with the case of PVDF resin alone. Since the heat resistance drop due to the addition of the agent can be greatly improved and the heat resistance almost equal to or higher than that of PVDF resin alone can be realized, PVDF resin can be used in industrial fields where higher heat resistance is required. can do.

  In addition, the PVDF resin composition of the present invention can suppress thermal decomposition and thermal discoloration during molding, and the thermal decomposition and thermal discoloration with time are remarkably suppressed, and appearance and hiding power (light scattering property). Since it has the effect of being excellent in heat resistance and durability, it can be usefully used as a raw material for a colored resin film. Furthermore, the colored resin film of the present invention can be used as a back sheet for a solar cell module excellent in durability and power generation efficiency.

71: Solar cell module 72: Surface protective material 73: Sealing material 74: Solar cell 75: Wiring 76: Back surface protective material (back sheet)

Claims (12)

  A polyvinylidene fluoride resin composition comprising 0.5 to 70 parts by weight of talc as a heat stabilizer with respect to 100 parts by weight of a polyvinylidene fluoride resin.   The polyvinylidene fluoride resin composition according to claim 1, comprising 0.8 to 50 parts by weight of the talc. The polyvinylidene fluoride resin composition according to claim 1, further comprising a colorant,
(A) The content of the colorant is 2 to 60 parts by weight with respect to 100 parts by weight of the polyvinylidene fluoride resin,
(B) The content ratio of talc is 2 to 60 parts by weight with respect to 100 parts by weight of the polyvinylidene fluoride resin, and
(C) The polyvinylidene fluoride resin composition having a weight ratio of the colorant to talc of 20: 1 to 1:20.   The polyvinylidene fluoride resin composition according to any one of claims 1 to 3, wherein the polyvinylidene fluoride resin is at least one selected from the group consisting of a vinylidene fluoride homopolymer and a vinylidene fluoride copolymer.   The vinylidene fluoride copolymer has a copolymerization ratio of 15 mol% or less with a vinylidene fluoride unit, vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-tetrafluoroethylene copolymer, fluoride Vinylidene-chlorotrifluoroethylene copolymer, vinylidene fluoride-trifluoroethylene copolymer, vinylidene fluoride-tetrafluoroethylene-hexafluoropropylene terpolymer, and vinylidene fluoride-chlorotrifluoroethylene-hexafluoro 5. The polyvinylidene fluoride resin composition according to claim 4, which is at least one vinylidene fluoride copolymer selected from the group consisting of propylene terpolymers. 6. The polyfluorinated product according to claim 1, wherein the talc has an average particle diameter (D ₅₀ ) of 0.5 to 20 μm and an apparent density of 0.05 to 0.5 g / cm ³ . Vinylidene resin composition.   The polyvinylidene fluoride resin composition according to any one of claims 1 to 6, further comprising another thermoplastic resin at a ratio of 30 parts by weight or less with respect to 100 parts by weight of the polyvinylidene fluoride resin.   The polyvinylidene fluoride resin composition according to claim 7, wherein the other thermoplastic resin is polymethyl methacrylate.   The polyvinylidene fluoride resin composition according to any one of claims 3 to 8, wherein the colorant is at least one selected from the group consisting of titanium oxide and carbon black.   100 weight of polyvinylidene fluoride resin, other additives which are at least one selected from the group consisting of pigment dispersants, ultraviolet absorbers, light stabilizers, matting agents, lubricants, color modifiers, crystal nucleating agents, and elastomers The polyvinylidene fluoride resin composition according to any one of claims 3 to 9, further comprising 10 parts by weight or less each independently with respect to parts.   A colored resin film formed from the polyvinylidene fluoride resin composition according to claim 3.   The solar cell module backsheet containing the layer which consists of a colored resin film of Claim 11.

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