WO2012077469A1

WO2012077469A1 - Resin film and manufacturing method therefor

Info

Publication number: WO2012077469A1
Application number: PCT/JP2011/076319
Authority: WO
Inventors: 畠山　晶; 和史古川; ゆきえ渡邊; 一路尼崎
Original assignee: 富士フイルム株式会社
Priority date: 2010-12-08
Filing date: 2011-11-15
Publication date: 2012-06-14
Also published as: JP2012121998A

Abstract

The present invention provides a method for manufacturing a resin film that forms a coating film that coats a surface well and exhibits excellent adhesion to an adjacent organic material. Said method comprises a step in which a coating fluid containing at least a compound represented by general formula (1) and a binder polymer is applied to a support, forming a polymer layer. (R^1a through R^1e each represent a monovalent substituent other than a hydroxy group (at least one of R^1a through R^1e represents a substituent for which σρ in the Hammett equation is at least 0.3, and the substituents represented by R^1a through R^1e may be bound to each other, forming a ring), and R^1g through R^1k, R^1m, R¹ⁿ, and R^1p each represent a hydrogen atom or a monovalent substituent (said substituents may be bound to each other, forming a ring).)

Description

Resin film and method for producing the same

The present invention relates to a resin film and a manufacturing method thereof.

2. Description of the Related Art Conventionally, a technique for imparting ultraviolet absorbing ability to enhance long-term durability is known. For example, a technique for incorporating an ultraviolet absorbent into polyester has been disclosed (see, for example, JP 2009-188105 A). .

As the ultraviolet absorber, inorganic and organic ultraviolet absorbers are known. Among these, organic ultraviolet absorbers have a higher degree of design freedom in compound structure than inorganic ultraviolet absorbers, and therefore, various absorption wavelengths can be obtained by devising the molecular structure. For this reason, various organic ultraviolet absorbers have been proposed, and as one example, a triazole ultraviolet absorber has been disclosed (for example, see JP-T-2002-524452). In addition, there is disclosure relating to trisaryl-s-triazine having an alkoxy group and a hydroxy group at specific positions (see, for example, Japanese Patent No. 3965631). However, those having a maximum absorption wavelength in the long wave ultraviolet region tend to have poor light resistance, and the ultraviolet shielding effect decreases with time. For this reason, in a usage form that is left for a long time under ultraviolet light exposure, the shielding effect cannot be maintained, so that the long-term durability cannot be greatly improved.

In particular, solar cells and the like that have been attracting attention in recent years are usually used outdoors under long periods of sunlight, and when the deterioration progresses gradually over a long period of time, the power generation performance decreases. Accordingly, there is a demand for a compound that exhibits a stable UV shielding effect over a long period of time in a wide ultraviolet region extending to the UV-A region (400 to 315 nm).

On the other hand, conventional benzophenone and benzotriazole UV absorbers have relatively good light resistance, and if the concentration and film thickness are increased, UV rays can be cut relatively clearly up to the long wavelength region. (For example, refer to JP-A-6-145387 and JP-A-2003-177235).

As described above, in recent years, solar cells have attracted attention as one of applications that are used for a long time in an environment that is easily exposed to ultraviolet rays. A solar cell module is generally a transparent glass substrate disposed on the side on which sunlight is directly incident, and a so-called back sheet for protecting the back surface disposed on the side opposite to the side on which sunlight is incident (back side). Between the two solar cells. The space between the glass and the solar battery cell and the space between the solar battery cell and the back sheet are generally sealed with a sealing agent such as EVA (ethylene-vinyl acetate) resin.

The back sheet has a function of preventing moisture from entering from the back surface of the solar cell module, and polyester is used from the viewpoint of cost and the like. As a backsheet using polyester, for example, a sheet having a polyester support provided with a light-reflective colored layer or a layer that easily adheres to a sealing material is known (for example, Japanese Patent Application Laid-Open No. 2007-2007). 118267).

However, when exposed to ultraviolet rays or the like for a long time, it is difficult to absorb over a wide area up to 400 nm in the long wave ultraviolet (UV-A) region. The fact is that it has not yet been able to ensure the durability performance to withstand. In addition, when exposed to sunlight, not only the light receiving surface but also the side portion and the back surface due to reflection or the like, so that the durability of the back sheet disposed on the back surface is greatly affected. Therefore, establishment of a technique capable of maintaining a stable UV shielding effect over a long period in a wide ultraviolet region including the UV-A region is required.

On the other hand, UV absorbers are generally used by mixing with resin, etc. However, in the method of increasing the concentration of UV absorber and the thickness of the film containing it, the thickness is limited to about several tens of μm. In order to impart ultraviolet absorbing ability in the long wavelength region, an ultraviolet absorber must be contained at a high concentration. However, if it is simply contained in a high concentration, there is a problem that the ultraviolet absorber is liable to precipitate, causes bleed out during long-term use, and deteriorates odor.

In addition, benzophenone-based and benzotriazole-based UV absorbers known in the past often have low solubility, so there is a problem that it is actually difficult to form a coating film well by the conventional coating method. .

The present invention has been made in view of the above, a method for producing a resin film that forms a coating film having a good coating surface shape and excellent adhesion between adjacent organic materials, and a long-wave ultraviolet light around 400 nm. An object of the present invention is to provide a resin film that has an ultraviolet shielding effect in a wide wavelength region including the (UV-A) region, exhibits excellent light resistance, and has a good surface shape and excellent adhesion of the coating layer. The goal is to achieve this.

Specific means for achieving the above object are as follows.
<1> A method for producing a resin film having a polymer layer forming step of forming a polymer layer by applying a coating liquid containing at least a compound represented by the following general formula (1) and a binder polymer on a support. .

In the general formula (1), R ^1a , R ^1b , R ^1c , R ^1d , and R ^1e each independently represent a monovalent substituent other than a hydroxy group, and at least one of R ^1a to R ^1e Represents a substituent having a Hammett's rule σp value of 0.3 or more. The substituents represented by R ^1a to R ^1e may be bonded to each other to form a ring. R ^1g , R ^1h , R ¹ⁱ , R ^1j , R ^1k , R ^1m , R ¹ⁿ , and R ^1p each independently represent a hydrogen atom or a monovalent substituent, and the substituents are bonded to each other A ring may be formed.

<2> R ^1a , R ^1c , and R ^{1e in the} general formula (1) represent a hydrogen atom, and at least one of R ^1b and R ^1d is an alkoxycarbonyl group (COOR _n [R _n : alkyl group]), <1> which is a nitro group (NO ₂ ), a cyano group (CN), a fluoroalkyl group (R _f ), a sulfonic acid or an alkali metal salt thereof (SO ₃ H or SO ₃ M [M: alkali metal]) It is a manufacturing method of the resin film of description.
<3> The concentration of the compound represented by the general formula (1) in the coating liquid is 3% by mass to 9% by mass with respect to the total mass of the coating liquid, and the coating liquid of the binder polymer It is a manufacturing method of the resin film as described in said <1> or <2> whose density in the inside is 6 mass% or more and 25 mass% or less with respect to the total mass of a coating liquid.
<4> Further, the method includes a step of preparing a dispersion by dispersing the compound represented by the general formula (1) in a solvent,
In the polymer layer forming step, any one of the above <1> to <3>, wherein the coating liquid containing the compound represented by the general formula (1) in a dispersed state is applied using the dispersion liquid. It is a manufacturing method of the resin film as described in one.

<5> The method for producing a resin film according to any one of <1> to <4>, wherein a polymer selected from a fluorine-based polymer and a silicone-based polymer is contained as at least one of the binder polymers.
<6> The method for producing a resin film according to any one of <1> to <5>, wherein the coating liquid further contains a crosslinking agent that crosslinks the binder.
<7>
It is a manufacturing method of the resin film as described in said <6> whose said crosslinking agent is a carbodiimide type crosslinking agent and / or an oxazoline type crosslinking agent.
<8> The resin film according to <6> or <7>, wherein the content of the crosslinking agent in the polymer layer is 0.5% by mass or more and 40% by mass or less with respect to the binder polymer. It is a manufacturing method.
<9> The method for producing a resin film according to any one of <1> to <8>, wherein the coating liquid further contains a solvent, and 50% by mass or more of the solvent is water.
<10> The method for producing a resin film according to any one of <1> to <9>, wherein the support is a polyester base material.

<11> A colored layer forming step of forming a colored layer by applying a coating solution containing at least a pigment and a binder on a support opposite to the side on which the polymer layer is formed, 1> to the method for producing a resin film according to any one of <10>.
<12> In any one of the above items <1> to <11>, including a protective layer forming step of forming a protective layer by applying a coating solution for a protective layer containing at least the binder polymer on the polymer layer It is a manufacturing method of the resin film of description.
<13> Any one of the above <1> to <12>, which is used as a solar cell backsheet provided on a side opposite to a side on which solar light is incident on a battery side substrate in which a solar cell element is sealed with a sealing material It is a manufacturing method of the resin film as described in any one.

ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the resin film which forms the coating film excellent in the adhesiveness between the organic materials with favorable coating surface shape and adjacent can be provided. Also,
According to the present invention, a resin having an ultraviolet shielding effect in a wide wavelength region including a long-wave ultraviolet (UV-A) region near 400 nm, exhibiting excellent light resistance, and having a good surface shape and excellent adhesion of a coating layer. A film can be provided.

Hereinafter, the method for producing the resin film of the present invention will be described in detail, and the details of the resin film of the present invention will also be described through the description.

The method for producing a resin film of the present invention comprises a step of forming a polymer layer by applying a coating liquid containing at least a compound represented by the general formula (1) shown below and a binder polymer on a support (hereinafter referred to as a polymer layer). It may also be referred to as a “polymer layer forming step.”), And if necessary, further provided with other steps such as a drying step for heating and drying the coated film after coating. May be.

In the present invention, the triazole-based compound has low solubility and has been conventionally considered to be difficult to apply uniformly. However, a compound having a specific structure as an ultraviolet absorber (hereinafter sometimes abbreviated as UV agent) is used. Using the compound in a support, instead of kneading it into the support, it is formed by coating a mixed solution containing the compound together with a binder polymer, so that a good coated surface can be obtained and the coating amount is small (thin film). Since the UV agent is unevenly distributed in the vicinity of the support surface, excellent light resistance is maintained over a long period of time. In particular, the ultraviolet shielding effect is excellent in a wide range including a long wave ultraviolet (UV-A) region around 400 nm. Moreover, since the coating amount of the compound having a specific structure can be reduced, it is possible to form a coating film having excellent adhesion with an adjacent organic material (a support when applied to the support surface).

The polymer layer in the present invention is not particularly limited and may be any layer provided on the support depending on the application. For example, when the resin film of the present invention is applied to the use of a solar cell and used as a so-called back sheet for protecting the back surface disposed on the side opposite to the side on which sunlight directly enters (back side), Easy adhesion to improve the adhesion of the polymer layer to (1) a colored layer containing a colorant such as a pigment and a battery-side substrate (especially a sealing material such as EVA for sealing the solar cell element) provided with the solar cell element. Or a back surface protective layer provided on the side not facing the battery side substrate. The colored layer includes, for example, a white pigment, a reflective layer that reflects light that has passed through the solar cells and reaches the back sheet and returns to the solar cells, and a design layer that enhances the decorativeness of the appearance. It is.

In the polymer layer forming step in the present invention, a coating solution is applied on a support to form a polymer layer. By coating, for example, it is possible to form a thin film as compared with the case of pasting a film containing a UV agent, and many compounds represented by the following general formula (1) are present near the surface of the resin film. It can be unevenly distributed, and a higher UV shielding effect, that is, light resistance can be obtained with a smaller amount.

The dry thickness of the polymer layer is preferably 0.5 to 10.0 μm. When the thickness of the polymer layer is 0.5 μm or more, it exhibits a higher ultraviolet shielding effect with a thinner film, exhibits higher durability performance, and has good adhesion to the polymer support. In addition, when the thickness of the polymer layer is 10.0 μm or less, the surface shape becomes better, and the adhesive strength between the adjacent layer and the polymer substrate is excellent. That is, when the thickness of the polymer layer is in the range of 0.5 to 4.0 μm, the durability and planarity of the polymer layer are compatible, and the adhesion between the polymer substrate and the polymer layer is superior.
The thickness of the polymer layer is particularly preferably in the range of 1.0 to 5.0 μm.
The polymer layer may be provided as a single layer or may be provided with two or more layers.

The coating solution is a compound represented by the following general formula (1), a binder polymer, a solvent, and a dispersant, a surfactant, a crosslinking agent, a pigment, or a compound represented by the general formula (1) as necessary. And other components such as various additives such as UV absorbers. The coating liquid in the present invention preferably contains at least the compound represented by the general formula (1) in a dispersed state dispersed in the liquid.
The compound represented by the general formula (1) may be used after being dissolved in a solvent that dissolves the compound. However, it is preferable that the compound is dispersed in a solvent and is present as dispersed particles in the coating solution. When the compound represented by the general formula (1) is contained in the coating solution in a dispersed state, the layer is formed when the polymer layer is exposed to a moist heat environment or the like compared to the case where it is dissolved and contained. The phenomenon of exuding from the inside can be prevented.

Specifically, the method for producing a resin film of the present invention preferably includes a dispersion step of preparing a dispersion by dispersing the compound represented by the general formula (1) in a solvent. In the polymer layer forming step in the present invention, the dispersion prepared in the dispersing step, the binder polymer, and other components such as a surfactant and a crosslinking agent as necessary are mixed to form a coating solution for forming the polymer layer. A polymer layer is suitably formed by preparing and apply | coating this coating liquid on a support body.

Here, the dispersed state means a state (emulsion) in which a solution of the compound represented by the general formula (1) is dispersed in a water-insoluble phase (oil phase) in an aqueous medium (aqueous phase), and an aqueous solution. It includes both a dispersed state (suspension) in which a water-insoluble compound is dispersed in a medium in a solid state or a liquid state. By being contained in a dispersed state, it can be retained in the layer after forming the polymer layer, and the occurrence of bleed out is prevented.

In the dispersion step, for example, when preparing an emulsion, the compound represented by the general formula (1) is added to a solvent and stirred to prepare an oil phase in which the compound is dissolved. Is added to water as a dispersant and stirred to prepare an aqueous phase in which the water-soluble resin is dissolved, and then the oil phase is added to the aqueous phase and stirred.
Here, examples of the water-soluble resin include polyvinyl alcohol (PVA), methyl cellulose, and hydroxypropyl cellulose. Examples of the organic solvent include tetrahydrofuran, ethyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, and the like.

In addition, the presence of the compound represented by the general formula (1) in a dispersed state means that after preparing an emulsion (emulsion) or suspension shown below, after removing an organic solvent from the emulsion or suspension, A state in which the dispersion state can be visually confirmed to exist stably at 25 ° C. for at least one week. Specifically, it can be confirmed by measuring and comparing the average particle diameter of the dispersed particles immediately after the preparation of the emulsion and after at least one week has passed at 25 ° C.
The emulsion is prepared by adding 20 g of the compound represented by the general formula (1) to 100 g of an organic solvent (for example, tetrahydrofuran) and heating and stirring to prepare an oil phase in which the compound is dissolved. After adding 36 g of polyvinyl alcohol (water-soluble resin) to 250 g of water as a dispersant and heating and stirring to prepare a water phase in which PVA is dissolved, the oil phase is added to the water phase and stirring (apparatus: (Dissolver, rotational speed: 20000 rpm, stirring time: 10 minutes, stirring temperature: 25 ° C.).

The average particle diameter is a value obtained as a median diameter by a laser analysis / scattering particle size distribution measuring apparatus LA950 (manufactured by Horiba, Ltd.).

The coating liquid in the present invention is preferably an emulsion (or suspension) in which the compound represented by the general formula (1) is dispersed and contained, a binder polymer, and other surfactants and crosslinkers as necessary. It can be prepared by mixing the ingredients. As a disperser for dispersing the compound represented by the general formula (1), a known stirrer or the like can be used. For example, a disperser, a bead mill, a ball mill, an ultrasonic disperser or the like is preferably used. Can do.

The coating solution may be an aqueous system using water as a coating solvent or a solvent system using an organic solvent such as toluene or methyl ethyl ketone. In the former case, a mixed solvent of water and an organic solvent miscible with water is used. Also good. Especially, the form which used water as the solvent for the said coating liquid from a viewpoint of environmental impact is preferable, and the form whose 50 mass% or more is water with respect to all the solvents contained in a coating liquid is more preferable. The proportion of water in the total solvent is preferably 60% by mass or more, and more preferably 80% by mass or more.
A coating solvent may be used individually by 1 type, and may mix and use 2 or more types.

As a method for applying the coating solution, a conventionally known coating method can be appropriately selected. For example, a known coating method such as a gravure coater or a bar coater can be used.

(Compound represented by the general formula (1))
The coating solution for forming a polymer layer in the present invention contains at least one compound represented by the following general formula (1) as an ultraviolet absorber. This ultraviolet absorber absorbs longer-wave ultraviolet rays than conventional ultraviolet absorbers, and provides an ultraviolet shielding effect in a wide range including a long-wave ultraviolet (UV-A) region around 400 nm. Thereby, in the long-term use, superior light resistance performance can be maintained as compared with the conventional case.

The content concentration of the ultraviolet absorber represented by the general formula (1) in the coating liquid for forming the polymer layer is preferably 3% by mass or more and 9% by mass or less with respect to the total mass of the coating liquid. 5 mass% or more and 8.5 mass% or less are more preferable. When the content concentration is 3% by mass or more, a good coated surface shape is obtained, and excellent light resistance is maintained over a long period of time. In particular, in a wide range including a long wave ultraviolet (UV-A) region around 400 nm. Excellent ultraviolet shielding effect. In addition, when the content concentration is 10% by mass or less, a good coated surface shape can be obtained, and excellent light resistance can be maintained over a long period of time, and the occurrence of bleed out when a polymer layer is formed can be prevented. it can.

In the general formula (1), R ^1a , R ^1b , R ^1c , R ^1d , and R ^1e each independently represent a monovalent substituent other than a hydroxy group (OH group). The substituents represented by R ^1a to R ^1e may be bonded to each other to form a ring. At least one of the substituents represented by R ^1a to R ^1e is a group having a Hammett's Hammett's Hammett's substituent constant σp value of 0.3 or more.

The substituent represented by R ^1a , R ^1b , R ^1c , R ^1d , and R ^1e is not particularly limited as long as at least one of R ^1a to R ^{1e has} a Hammett's σp value of 0.3 or more. Preferred examples of the substituent having a Hammett's rule σp value of 0.3 or more include an alkoxycarbonyl group (COOR _n ), a nitro group (NO ₂ ), a cyano group (CN), a halogenated alkyl group (fluoroalkyl group (Rf)). ), Sulfonic acid or an alkali metal salt thereof (SO ₃ H or SO ₃ M).

In the above, R _n represents an alkyl moiety. The number of carbon atoms of the alkyl moiety represented by R _n of the alkoxycarbonyl group is preferably in the range of 1-20. The alkyl moiety may be linear or branched, and may further contain a double bond or a triple bond. Among these, the carbon number of the alkyl moiety is more preferably in the range of 1 to 10, and further preferably in the range of 1 to 5. Specific examples of the alkoxycarbonyl group include methoxycarbonyl group, ethoxycarbonyl group, n-butoxycarbonyl group, t-butoxycarbonyl group and the like.

The halogenated alkyl group is not particularly limited in the number of halogen substitutions, and may be arbitrarily selected. The kind of halogen is preferably a fluorine atom, a chlorine atom, a bromine atom or an iodine atom, among which a fluorine atom is particularly preferred. Among the halogenated alkyl groups, a fluoroalkyl group is preferable, a fluoroalkyl group having 1 to 5 carbon atoms is more preferable, and a perfluoroalkyl group having 1 to 5 carbon atoms is particularly preferable. The fluoroalkyl group may be either a straight chain or a branched chain, and may further contain a double bond or a triple bond. Specific examples of the fluoroalkyl group include a fluoromethyl group, a difluoroethyl group, a perfluoromethyl group, and a hexafluoropropyl group.

M in the SO ₃ M represents an alkali metal. As an alkali metal represented by M, lithium, sodium, or potassium is mentioned suitably, Especially sodium or potassium is more preferable.

When the substituent represented by R ^1a to R ^1e in the general formula (1) represents a monovalent group other than the above-described groups, the monovalent substituent (hereinafter referred to as “substituent A”). .) Includes, for example, the following groups. That is,
Specific examples of the substituent A include a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), an alkyl group having 1 to 20 carbon atoms (including a halogenated alkyl group. For example, methyl, ethyl, perfluoromethyl Fluoroethyl), aryl groups having 6 to 20 carbon atoms (eg phenyl, naphthyl), cyano groups, carboxyl groups, alkoxycarbonyl groups (eg methoxycarbonyl), aryloxycarbonyl groups (eg phenoxycarbonyl), carbamoyl groups (eg carbamoyl) , N-phenylcarbamoyl, N, N-dimethylcarbamoyl), alkylcarbonyl group (eg acetyl), arylcarbonyl group (eg benzoyl), nitro group, amino group (eg amino, dimethylamino, anilino, substituted sulfoamino group), acyl Amino group (e.g. acetamido, ethoxycarbonylamino), a sulfonamido group (e.g., methanesulfonamido), an imido group (e.g. succinimido, phthalimido), an imino group (e.g., benzylideneamino), a hydroxy group ^{^{^{(R 1a, R 1b, R}}} 1c, Not included in the monovalent substituent represented by R ^1d and R ^1e ), an alkoxy group having 1 to 20 carbon atoms (for example, methoxy), an aryloxy group (for example, phenoxy), an acyloxy group (for example, acetoxy), Alkylsulfonyloxy group (for example, methanesulfonyloxy), arylsulfonyloxy group (for example, benzenesulfonyloxy), sulfo group, sulfamoyl group (for example, sulfamoyl, N-phenylsulfamoyl), alkylthio group (for example, methylthio), arylthio group For example, phenylthio), a thiocyanate group, an alkylsulfonyl group (e.g. methanesulfonyl), an arylsulfonyl group (e.g., benzenesulfonyl), and the like Hajime Tamaki having 6 to 20 carbon atoms (for example, pyridyl, morpholino).
The monovalent substituent may be unsubstituted, may be further substituted with a substituent, and when having a plurality of substituents, the plurality of substituents may be the same or different. Examples of the substituent in the case of being substituted with a substituent include the groups listed as examples of the “monovalent substituent A”. Moreover, substituents may couple | bond together and a ring may be formed.

Examples of the ring formed by bonding substituents include benzene ring, pyridine ring, pyrazine ring, pyrimidine ring, triazine ring, pyridazine ring, pyrrole ring, pyrazole ring, imidazole ring, triazole ring, oxazole ring, oxadi Examples thereof include an azole ring, a thiazole ring, a thiadiazole ring, a furan ring, a thiophene ring, a selenophene ring, a silole ring, a gelmol ring, and a phosphole ring.

As the monovalent substituent A in the general formula (1), a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms (including a halogenated alkyl group), a cyano group, a carboxyl group, substituted or unsubstituted An alkoxycarbonyl group having 1 to 20 carbon atoms in the unsubstituted alkyl moiety, a substituted or unsubstituted carbamoyl group, an alkylcarbonyl group having 1 to 20 carbon atoms in the substituted or unsubstituted alkyl moiety, a nitro group, substituted or unsubstituted A substituted amino group, a hydroxy group (not included in the monovalent substituent represented by R ^1a , R ^1b , R ^1c , R ^1d , R ^1e ), a substituted or unsubstituted C 1-20. An alkoxy group, a substituted or unsubstituted aryloxy group having 6 to 20 carbon atoms, a substituted or unsubstituted sulfamoyl group, a thiocyanate group, or a substituted or unsubstituted alkyl moiety having 1 carbon atom Preferred alkylsulfonyl groups of 20. Among these, a hydroxy group (not included in the monovalent substituent represented by R ^1a , R ^1b , R ^1c , R ^1d , and R ^1e ), an alkoxy group having 1 to 20 carbon atoms, and a carbon number of 6 Are more preferably an aryloxy group having ˜20, an alkyl group having 1 to 20 carbon atoms, and an amide group, and the monovalent substituent represented by a hydroxy group (R ^1a , R ^1b , R ^1c , R ^1d , R ^1e is Not more preferred), an alkoxy group having 1 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, and an alkyl group having 1 to 20 carbon atoms are more preferred.
The alkyl moiety of the alkoxy group is preferably a linear or branched alkyl group having 1 to 20 carbon atoms, and more preferably a linear or branched alkyl group having 1 to 6 carbon atoms. Examples of the linear or branched alkyl group having 1 to 6 carbon atoms include methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl, t-butyl, n-pentyl, i -Pentyl, t-pentyl, n-hexyl, i-hexyl, t-hexyl, n-octyl, t-octyl, i-octyl can be mentioned, methyl or ethyl is preferred, and methyl is particularly preferred.

Of the R ^1a , R ^1b , R ^1c , R ^1d and R ^1e , as a preferred first aspect of the present invention, at least one of R ^1a , R ^1c and R ^1e represents a monovalent substituent, There is an embodiment in which at least one of the substituents represents a substituent having a positive Hammett's σp value. Among these, an embodiment in which R ^1c represents a substituent having a positive Hammett's σp value is more preferable. Further, it is more preferable that R ^1c is a substituent having a positive Hammett's σp value, and R ^1a , R ^1b , R ^1d , and R ^1e represent a hydrogen atom. When R ^1c represents a substituent having a positive Hammett's σp value, LUMO is stabilized by the electron-attracting group, which is preferable because the excitation lifetime is shortened and the light resistance is improved.

In the first aspect, the “substituent in which the Hammett's σp value is positive” in R ^1a , R ^1c , and R ^1e in the general formula (1) preferably has a σp value of 0.1 to 1. 2 electron withdrawing groups. As specific examples of the electron withdrawing group having a σp value of 0.1 or more, COOR ^r (R ^r represents a hydrogen atom or a monovalent substituent, preferably a hydrogen atom or an alkyl group, more preferably CONR ^s ₂ (R ^s represents a hydrogen atom or a monovalent substituent), CN, halogen atom, NO ₂ , SO ₃ M (M represents a hydrogen atom or an alkali metal). .), Acyl group, formyl group, acyloxy group, acylthio group, alkyloxycarbonyl group, aryloxycarbonyl group, dialkylphosphono group, diarylphosphono group, dialkylphosphinyl group, diarylphosphinyl group, phosphoryl group, Alkylsulfinyl group, arylsulfinyl group, acylthio group, sulfamoyl group, thiocyanate group, thiocarbonyl group, imino group, N atom An imino group substituted with a child, a carboxyl group (or a salt thereof), an alkyl group substituted with at least two or more halogen atoms (for example, CF ₃ ), an alkoxy group substituted with at least two or more halogen atoms, at least An aryloxy group substituted with two or more halogen atoms, an acylamino group, an alkylamino group substituted with at least two halogen atoms, an alkylthio group substituted with at least two halogen atoms, or a σp value of 0 And aryl groups, heterocyclic groups, halogen atoms, azo groups, and selenocyanate groups substituted with two or more other electron-withdrawing groups.
Hammett σp values are described in detail in Hansch, C .; Leo, A .; Taft, R. W. Chem. Rev. 1991, 91, 165-195.

The “substituent having a positive Hammett's σp value” is more preferably COOR ^r , CONR ^s ₂ , CN, CF ₃ , a halogen atom, NO ₂ , from the viewpoint of excellent light resistance and solubility. And SO ₃ M. Here, R ^r and R ^s each independently represent a hydrogen atom or a monovalent substituent. M represents a hydrogen atom or an alkali metal (the same applies to M hereinafter). ). Among them, the “substituent having a positive Hammett's σp value” is more preferably COOR ^r or CN, and particularly preferably COOR ^r for the same reason as above.

R ^r and R ^{s each} represent a hydrogen atom or a monovalent substituent, and examples of the monovalent substituent herein include the substituent A. Of these, a linear or branched alkyl group having 1 to 20 carbon atoms is preferable, and a linear or branched alkyl group having 1 to 6 carbon atoms is more preferable. Examples of the linear or branched alkyl group having 1 to 6 carbon atoms include methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl, t-butyl, and n-pentyl. , I-pentyl, t-pentyl, n-hexyl, i-hexyl, t-hexyl, n-octyl, t-octyl, i-octyl, methyl or ethyl is preferable, and methyl is particularly preferable.
Examples of the alkali metal represented by M include lithium, sodium, and potassium, and sodium and potassium are particularly preferable (hereinafter the same applies to M).

In the compound represented by the general formula (1), it is preferable that R ^1c is any one of COOR ^r , CONR ^s ₂ , CN, CF ₃ , a halogen atom, NO ₂ , SO ₃ M, and further, COOR ^The aspect which is ^r or CN is more preferable, and the aspect which is CN is still more preferable.

In the general formula (1), R ^1g , R ^1h , R ¹ⁱ , R ^1j , R ^1k , R ^1m , R ¹ⁿ , and R ^1p each independently represent a hydrogen atom or a monovalent substituent, The substituents may be bonded to each other to form a ring.

When R ^1g , R ^1h , R ¹ⁱ , R ^1j , R ^1k , R ^1m , R ¹ⁿ and R ^1p represent a monovalent substituent, R ^1g , R ^1h , R ¹ⁱ , R ^1j , R ^1k , R ^1m , R ¹ⁿ and R ^1p preferably represent the “substituent having a positive Hammett σp value”, and at least one of R ^1g , R ^1h , R ¹ⁱ and R ^1j It is more preferable that the σp value of the rule is positive (preferably 0.1 to 1.2) ”, and R ^1h represents the“ substituent whose σp value of the Hammett rule is positive ”. More preferably, it represents.

In the present invention, particularly when R ¹ⁿ and R ^1h represent the above-mentioned “substituents whose Hammett's σp value is positive (preferably 0.1 to 1.2)” in view of excellent light resistance. preferable.

In the present invention, R ^1h or R ¹ⁿ is independently a hydrogen atom, COOR ^r , CONR ^s ₂ , CN, CF ₃ , halogen atom, NO ₂ , SO ₃ M, or the like, in that it exhibits excellent light resistance. R ^1h or R ¹ⁿ is preferably a hydrogen atom, R ^1h and R ¹ⁿ are more preferably a hydrogen atom, and R ^1g , R ^1h , R ¹ⁱ , R ^1j , R ^1k , R ^1m , R ¹ⁿ and R ^1p particularly preferably represent a hydrogen atom.

In the compound represented by the general formula (1), R ^1c is “a substituent having a positive Hammett's σp value (preferably 0.1 to 1.2)” in that it exhibits excellent light resistance. R ^1g , R ^1h , R ¹ⁱ , R ^1j , R ^1k , R ^1m , R ¹ⁿ and R ^1p are preferably hydrogen atoms, and R ^1c is COOR ^r , CONR ^s ₂ , CN, CF ₃ , More preferably, it is any one of a halogen atom, NO ₂ , and SO ₃ M, and R ^1g , R ^1h , R ¹ⁱ , R ^1j , R ^1k , R ^1m , R ^1n, and R ^1p are hydrogen atoms.

The compound represented by the general formula (1) preferably has a pKa in the range of −5.0 to −7.0, more preferably in the range of −5.2 to −6.5. More preferably, it is in the range of -5.4 to -6.0.

As a preferred second embodiment of the present invention, R ^1a , R ^1c and R ^1e each represent a hydrogen atom, R ^1b and R ^1d each independently represent a monovalent substituent, and R ^1b and R ^1d An embodiment in which at least one is a substituent having a positive Hammett's σp value can be given. Thereby, especially the compound represented by General formula (1) is excellent in solvent solubility. Compatibility with polymer (especially because of excellent compatibility with polyester, when a polyester resin composition containing the compound is used, precipitation or bleeding out of the compound represented by the general formula (1) is difficult to occur. It has the effect.
Here, the solvent solubility means solubility in an organic solvent such as ethyl acetate, methyl ethyl ketone, and toluene. In terms of compatibility with the polymer (particularly compatibility with the polyester), it is preferably 10% by mass or more, more preferably 30% by mass or more, based on the solvent used.

In the second aspect, the “substituent having a positive Hammett's σp value” in R ^1b and R ^1d in the general formula (1) is preferably COOR ^r , CONR ^s ₂ , CN, CF _3. , A halogen atom, NO ₂ , and SO ₃ M. Here, R ^r and R ^s each independently represent a hydrogen atom or a monovalent substituent. M represents a hydrogen atom or an alkali metal. ^{Examples of} the monovalent substituent represented by R ^r and R ^s include the substituent A described above.
Among these, an alkoxycarbonyl group, a nitro group, a cyano group, a fluoroalkyl group, and a sulfonic acid or an alkali metal salt thereof are preferable.

As the "substituent σp value of Hammett's rule is positive" is a point showing the solubility and excellent light resistance, more preferably COOR ^r or a cyano group, it is preferably further is COOR ^r. When the “substituent having a positive Hammett's σp value” is a cyano group, it exhibits better light resistance, and when the “substituent having a positive Hammett's σp value” is COOR ^r , Better solvent solubility.

R ^r preferably represents a hydrogen atom or an alkyl group, more preferably a linear or branched alkyl group having 1 to 20 carbon atoms, and still more preferably a linear or branched alkyl group having 1 to 15 carbon atoms. . R ^r is more preferably a branched alkyl group having 5 to 15 carbon atoms from the viewpoint of solubility in a solvent.
The branched alkyl group has a secondary carbon atom or a tertiary carbon atom, preferably contains 1 to 5 secondary carbon atoms or tertiary carbon atoms, preferably contains 1 to 3, preferably 1 or It is preferable to include two, and it is more preferable to include one or two secondary carbon atoms and tertiary carbon atoms. Further, it preferably contains 1 to 3 asymmetric carbons.
From the viewpoint of solubility in a solvent, R ^r is a branched alkyl group having 5 to 15 carbon atoms containing 1 or 2 secondary carbon atoms and tertiary carbon atoms and 1 or 2 asymmetric carbon atoms. It is particularly preferred.
This is because the symmetry of the compound structure is lost and the solubility is improved.

On the other hand, from the viewpoint of ultraviolet absorbing ability, a linear or branched alkyl group having 1 to 6 carbon atoms is more preferable. Examples of the linear or branched alkyl group having 1 to 6 carbon atoms include methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl, t-butyl, n-pentyl, i -Pentyl, t-pentyl, n-hexyl, i-hexyl, t-hexyl, n-octyl, t-octyl, i-octyl can be mentioned, methyl or ethyl is preferred, and methyl is particularly preferred.

In the present invention, when R ^1g , R ^1h , R ¹ⁱ , R ^1j , R ^1k , R ^1m , R ¹ⁿ and R ^1p represent a monovalent substituent in terms of exhibiting excellent light resistance, More preferably, at least one of ^1g , R ^1h , R ¹ⁱ , R ^1j , R ^1k , R ^1m , R ¹ⁿ and R ^{1p represents} the above-mentioned “substituent with a positive Hammett σp value”, R ^1g , More preferably, at least one of R ^1h , R ¹ⁱ and R ^1j represents the “substituent whose Hammett's σp value is positive (preferably 0.1 to 1.2)”, and R ^1h represents the “Hammett More preferably, it represents a “substituent whose σp value of the rule is positive”. It is particularly preferable that R ^1b or R ^1d and R ^1h represent the above-mentioned “substituents whose Hammett's σp value is positive (preferably 0.1 to 1.2)”.
In the present invention, R ^1h or R ¹ⁿ is independently any one of a hydrogen atom, COOR ^r , CONR ^s ₂ , a cyano group, CF ₃ , a halogen atom, a nitro group, and SO ₃ M in that excellent light resistance is exhibited. R ^1h or R ¹ⁿ is preferably a hydrogen atom, R ^1h and R ¹ⁿ are more preferably a hydrogen atom, and R ^1g , R ^1h , R ¹ⁱ , R ^1j , R ^1k R ^1m , R ¹ⁿ and R ^1p particularly preferably represent a hydrogen atom.

In the compound represented by the general formula (1), R ^1b , R ^1c or R ^1d is “a Hammett's σp value is positive (preferably 0.1 to 1.2). It is preferable that R ^1g , R ^1h , R ¹ⁱ , R ^1j , R ^1k , R ^1m , R ¹ⁿ and R ^1p are hydrogen atoms, and R ^1b , R ^1c or R ^1d Is one of COOR ^r , CONR ^s ₂ , cyano group, CF ₃ , halogen atom, nitro group, or SO ₃ M, and R ^1g , R ^1h , R ¹ⁱ , R ^1j , R ^1k , R ^1m , R More preferably, ¹ⁿ and R ^1p are hydrogen atoms.
Particularly preferably, R ^1a , R ^1b , R ^1d , R ^1e , R ^1g , R ^1h , R ¹ⁱ , R ^1j , R ^1k , R ^1m , R ¹ⁿ , and R ^1p are hydrogen atoms, and R ^1c is COOR ^r [R ^r represents a monovalent substituent. ].

Specific examples of the compound represented by the general formula (1) (Exemplary compounds 1 to 120, m-1 to m-70) are shown below. However, the present invention is not limited to these. In the following specific examples, Me represents a methyl group, Ph represents a phenyl group, and —C ₆ H ₁₃ represents n-hexyl.

The compound represented by the general formula (1) can take a tautomer depending on the structure and the environment in which the compound is placed, but the compound represented by the general formula (1) includes a tautomer. .

The compound represented by the general formula (1) may contain an isotope (for example, ² H, ³ H, ¹³ C, ¹⁵ N, ¹⁷ O, ¹⁸ O, etc.).

The compound represented by the general formula (1) can be synthesized by any method.
For example, known patent documents and non-patent documents (for example, JP-A-7-188190, JP-A-11-315072, JP-A-2001-220385, “Dye and Drug”, Vol. 40, No. 12 (1995) ), Pages 325 to 339) and the like. Specifically, the exemplified compound (16) can be synthesized by reacting salicylamide, 3,5-bis (trifluoromethyl) benzoyl chloride and 2-hydroxybenzamidine hydrochloride. Alternatively, it can be synthesized by reacting salicylamide, salicylic acid and 3,5-bis (trifluoromethyl) benzamidine hydrochloride.

The compound represented by the general formula (1) has a feature of excellent solubility in an organic solvent, and has a “substituent having a positive Hammett's σp value” at a specific position in the structural formula. Since LUMO is stabilized by the electron withdrawing group, the excitation life is shortened and the light resistance is excellent. Therefore, when used as a UV absorber, conventional UV absorbers such as triazine compounds, when used at a high concentration, have adverse effects such as precipitation, bleeding out due to long-term use, or yellowing due to decomposition. However, since the compound represented by the general formula (1) in the present invention has excellent solubility and light resistance, precipitation and bleed-out do not occur even when it is contained at a high concentration, and it takes a long time. Even when used, yellowing can be prevented without decomposition.

The compound represented by the general formula (1) may be used alone or in combination of two or more having different structures.

The maximum absorption wavelength of the compound represented by the general formula (1) is not particularly limited, but is preferably 250 to 400 nm, and more preferably 280 to 380 nm. The full width at half maximum is preferably 20 to 100 nm, more preferably 40 to 80 nm.
The maximum absorption wavelength and the full width at half maximum are values easily measured by a conventionally known method. The measurement method is described in, for example, “The Fourth Edition Experimental Chemistry Course 7 Spectroscopy II” (Maruzen, 1992), pages 180 to 186, edited by the Chemical Society of Japan. Specifically, the sample is dissolved in an appropriate solvent, and measurement is performed by a spectrophotometer using two cells for sample and control using a cell made of quartz or glass. The solvent is required to have no absorption in the measurement wavelength region, have a small interaction with the solute molecule, and have a very low volatility in accordance with the solubility of the sample. The maximum absorption wavelength and half width in the present invention are values measured by preparing a solution having a concentration of about 5 × 10 ⁻⁵ mol · dm ⁻³ using ethyl acetate and using a quartz cell having an optical path length of 10 mm.

The half width of the spectrum is described in, for example, “Chapter 4 of Experimental Chemistry Lecture 3, Basic Operation III” (Maruzen, 1991), page 154, edited by the Chemical Society of Japan. In the written book, the half width may be explained with an example in which the horizontal axis is taken on the wave number scale, but the half width in the present invention uses a value obtained on the axis on the wavelength scale. The unit of the half width is [nm]. Specifically, it represents the width of the absorption band that is half the absorbance at the maximum absorption wavelength, and is used as a value that represents the shape of the absorption spectrum. A spectrum with a small half-value width shows a sharp spectrum, and a spectrum with a large half-value width shows a broad spectrum. UV-absorbing compounds that give a broad spectrum also have absorption in a wide range from the maximum absorption wavelength to the long wave side, so there is no yellowish coloration, and a spectrum with a small half-value width is effective for shielding the long wave ultraviolet region. A UV-absorbing compound having is preferred.

The intensity of light absorption, that is, oscillator strength, is proportional to the integral of the molar extinction coefficient, as described in Sumida Tokita “Chemical Seminar 9 Color Chemistry” (Maruzen, 1982), pages 154 to 155. When the symmetry of the spectrum is good, the oscillator strength is proportional to the product of the absorbance at the maximum absorption wavelength and the full width at half maximum (however, the full width at half maximum is a value centered on the wavelength scale). This means that when the transition moment values are the same, a compound having a spectrum with a small half width has a large absorbance at the maximum absorption wavelength. Such UV-absorbing compounds have the advantage of being able to effectively shield the area around the maximum absorption wavelength with a small amount of use, but since the absorbance decreases sharply when the wavelength is slightly away from the maximum absorption wavelength, a wide range of areas can be used. It cannot be shielded.

The compound represented by the general formula (1) preferably has a molar extinction coefficient at the maximum absorption wavelength of 20000 or more, more preferably 30000 or more, and particularly preferably 50000 or more. When the molar extinction coefficient is 20000 or more, the absorption efficiency per mass of the compound represented by the general formula (1) is high, and therefore, it is represented by the “general formula (1) required to completely absorb the ultraviolet region. The amount of “compound” can be reduced. This is preferable from the viewpoint of preventing skin irritation and accumulation in a living body and from the point that bleeding out hardly occurs.
The molar extinction coefficient is described in, for example, “New Edition Experimental Chemistry Course 9 Analytical Chemistry [II]” (Maruzen, 1977), page 244, edited by the Chemical Society of Japan. It can be obtained together.

The content of the ultraviolet absorber represented by the general formula (1) in the formed polymer layer is preferably 0.15 to 5.0 g / m ² , and preferably 0.3 to 4.0 g / m ^2. More preferred. When the content is 0.15 g / m ² or more, the ultraviolet shielding effect is excellent in a wide range including a long-wave ultraviolet (UV-A) region near 400 nm. Moreover, generation | occurrence | production of bleed-out can be prevented because content is 5.0 g / m < ² > or less.

The coating solution for forming a polymer layer in the present invention may contain two or more compounds represented by the general formula (1) having different structures as an ultraviolet absorber. Moreover, you may use together the compound represented by the said General formula (1), and 1 or more types of other ultraviolet absorbers other than that. When two types (preferably three types) of ultraviolet absorbers having different basic skeleton structures are used in combination, the dispersion state of the ultraviolet absorber is stabilized and ultraviolet rays in a wide wavelength region can be absorbed.
Examples of other ultraviolet absorbers other than the general formula (1) include triazine, benzotriazole, benzophenone, merocyanine, cyanine, dibenzoylmethane, cinnamic acid, cyanoacrylate, and benzoate. And the like. Specifically, fine chemicals (May 2004 issue, pages 28-38), “New development of functional additives for polymers” (published by Toray Research Center, Research Division, pages 96-140, 1999), “ Examples include ultraviolet absorbers described in “Development of Polymer Additives and Environmental Measures” (supervised by Junichi Daikatsu, CMC Publishing, pages 54 to 64, 2003).

Examples of the other ultraviolet absorbers include benzotriazole compounds, benzophenone compounds, salicylic acid compounds, benzoxazinone compounds, cyanoacrylate compounds, benzoxazole compounds, merocyanine compounds, and triazine compounds. More preferred are benzoxazinone compounds, benzotriazole compounds, benzophenone compounds, triazine compounds and the like. Particularly preferred are benzoxazinone compounds. Other ultraviolet absorbers are described in detail in paragraphs [0117] to [0121] of JP-A-2008-273950, and the materials described in the publication can be applied.
When other ultraviolet absorbers are used in combination, the content ratio of the other ultraviolet absorbers is based on the amount of the ultraviolet absorber represented by the general formula (1) from the viewpoint of maintaining the effects of the present invention. 20 mass% or less is preferable.

The compound represented by the general formula (1) is preferably contained in combination with a benzoxazinone compound. Since the compound represented by the general formula (1) has excellent light resistance in the long wavelength region, it has the effect of preventing the deterioration of benzoxazinone that can be shielded to a longer wavelength region, together with the benzoxazinone-based compound. Use is preferable because the shielding effect can be sustained for a long time up to a longer wavelength region.

By containing the compound represented by the general formula (1) as an ultraviolet absorber, a high ultraviolet shielding effect can be obtained, and furthermore, a white pigment having a strong hiding power, such as titanium oxide, may be used in combination.
Further, a slight amount (0.05% by mass or less) of a colorant may be used in combination depending on the viewpoint of appearance, color tone or preference. In applications where it is important to be transparent or white, a fluorescent brightener may be used in combination. Examples of the fluorescent brightening agent include commercially available products, general formula [1] described in JP-A-2002-53824, and specific compound examples 1 to 35.

(Binder polymer)
The coating solution for forming a polymer layer in the present invention contains at least one binder polymer. By allowing the binder polymer and the compound represented by the general formula (1) to be present in the same layer together with the binder polymer and the compound represented by the general formula (1) in separate layers, A state in which the compound represented by the general formula (1) is wrapped with a polymer is formed, and deterioration of the compound itself can be prevented.

Examples of the binder polymer include silicone polymers (for example, silicone-acrylic composite polymer, silicone-polyester composite polymer), polyester-based polymers (for example, polyethylene terephthalate (PET), polyethylene-2,6-naphthalate (PEN)). ), Etc.), polyurethane polymers (eg, polymers comprising hexamethylene diisocyanate or toluene diisocyanate and ethylene glycol or propylene glycol), acrylic polymers (eg, polymers containing polymethyl methacrylate, polyethyl acrylate, etc.), Appropriately selected from known polymers such as polyolefin polymers (for example, polymers composed of polyethylene and acrylic acid or methacrylic acid) It can be used Te.

Among these, adhesion between the support or other layers such as a colored layer and an undercoat layer, and weather resistance (particularly in a high humidity environment with temperature and humidity changes and heat and moisture (humidity)) From the viewpoint of ensuring (resistance), it is preferable to include at least one selected from the group consisting of polyester polymers, polyurethane polymers, fluorine polymers, and silicone polymers.
Furthermore, the compound represented by the general formula (1) is incorporated to prevent deterioration of itself more effectively, and is resistant to weathering (particularly in a high humidity environment having changes in temperature and humidity, heat and moisture (humidity)). In view of further improving resistance, a fluorine-based polymer and a silicone-based polymer are preferable, and a silicone-based polymer is particularly preferable.

As the fluoropolymer, a polymer having a repeating unit represented by-(CFX ¹ -CX ² X ³ )-is preferable. In the repeating unit, X ¹ , X ² , and X ³ each independently represent a hydrogen atom, a fluorine atom, a chlorine atom, or a perfluoroalkyl group having 1 to 3 carbon atoms.

Examples of the fluorine-based polymer include polytetrafluoroethylene (hereinafter sometimes referred to as PTFE), polyvinyl fluoride (hereinafter sometimes referred to as PVF), and polyvinylidene fluoride (hereinafter referred to as PVDF). ), Polychlorinated ethylene trifluoride (hereinafter sometimes referred to as PCTFE), polytetrafluoropropylene (hereinafter sometimes referred to as HFP), and the like.

The fluoropolymer may be a homopolymer obtained by homopolymerizing one kind of monomer, or may be obtained by copolymerizing two or more kinds of monomers. As examples of the copolymerized copolymer, a copolymer obtained by copolymerizing tetrafluoroethylene and tetrafluoropropylene (abbreviated as P (TFE / HFP)), a copolymer obtained by copolymerizing tetrafluoroethylene and vinylidene fluoride (P ( Abbreviated as TFE / VDF)).

Further, it may be a polymer obtained by copolymerizing a fluorine-based monomer having a structural portion of-(CFX ¹ -CX ² X ³ )-and another monomer. For example, a copolymer of tetrafluoroethylene and ethylene (abbreviated as P (TFE / E)), a copolymer of tetrafluoroethylene and propylene (abbreviated as P (TFE / P)), Copolymer of tetrafluoroethylene and vinyl ether (abbreviated as P (TFE / VE)), copolymer of tetrafluoroethylene and perfluorovinyl ether (abbreviated as P (TFE / FVE)), chlorotri Copolymers of fluoroethylene and vinyl ether (abbreviated as P (CTFE / VE)), copolymers of chlorotrifluoroethylene and perfluorovinyl ether (abbreviated as P (CTFE / FVE)), and the like. be able to.

The fluoropolymer may be used by being dissolved in an organic solvent, or may be used by being dispersed in water as polymer particles. The latter is preferable in that the environmental load is small. The aqueous dispersions of fluoropolymers are described in, for example, Japanese Patent Application Laid-Open Nos. 2003-231722, 2002-20409, and 9-194538.

Commercially available products that are commercially available may be used as the fluoropolymer, and examples of the commercially available products include Obligato SW0011F manufactured by AGC Co-Tech Co., Ltd.

Examples of the silicone-based polymer include a composite polymer of silicone and acrylic, a composite polymer of silicone and polyester, and the like. Commercially available products that are marketed may be used as the silicone polymer. For example, as a specific example of a composite polymer of silicone and acrylic, Seranate WSA1060 and WSA1070 manufactured by DIC Corporation, Asahi Kasei Chemicals Corporation H7620, H7630, H7650, and the like.

The coating liquid for forming the polymer layer may be a combination of a fluorine-based polymer and / or a silicone-based polymer and a polymer other than these polymers. When other polymers are used in combination, it is preferable to use the polymers other than the fluorine-based polymer and the silicone-based polymer in the range of 50% by mass or less of the total mass of the binder. When the amount of the other polymer is 50% by mass or less, good weather resistance as a back sheet can be exhibited.

The concentration of the binder polymer in the coating solution for forming the polymer layer is preferably 6% by mass or more and 25% by mass or less, more preferably 8% by mass or more and 20% by mass or less, with respect to the total mass of the coating solution. It is. When the content of the binder polymer is 6% by mass or more, a layer having a good strength is obtained, and when the content is 25% by mass or less, the amount of the ultraviolet absorber is not relatively decreased. This is preferable for maintaining high light resistance.
The coating amount of the binder polymer in the formed polymer layer is preferably 1.0 to 8.5 g / m ² , more preferably 2.0 to 6.0 g / m ² or less. When the content of the polymer is 1.0 g / m ² , a layer having good strength can be obtained, and when it is 8.5 g / m ² or less, the amount of the UV absorber may be relatively too small. In view of maintaining high light resistance, it is preferable.

(Crosslinking agent)
The coating liquid for forming the polymer layer may contain a crosslinking agent for crosslinking the binder polymer contained in the polymer layer. Examples of the crosslinking agent include epoxy-based, isocyanate-based, melamine-based, carbodiimide-based, and oxazoline-based crosslinking agents. Of these, a carbodiimide-based crosslinking agent and an oxazoline-based crosslinking agent are preferable from the viewpoint of securing adhesiveness after wet heat aging.

Specific examples of the carbodiimide crosslinking agent include N, N′-dicyclohexylcarbodiimide, N, N′-diisopropylcarbodiimide, 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride, N- [3- ( And dimethylamino) propyl] -N′-ethylcarbodiimide, N- [3- (dimethylamino) propyl] -N′-propylcarbodiimide, N-tert-butyl-N′-ethylcarbodiimide, and the like.
Further, commercially available products include Carbodilite V-02-L2 (manufactured by Nisshinbo Industries, Inc.).

Specific examples of the oxazoline-based crosslinking agent include 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-isopropenyl-2- Oxazoline, 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl-5-ethyl-2-oxazoline, 2,2'-bis- (2-oxazoline), 2,2'-methylene-bis- (2-oxazoline), 2,2′-ethylene-bis- (2-oxazoline), 2,2′-trimethylene-bis- (2-oxazoline), 2,2′-tetramethylene-bis- (2-oxazoline) ), 2,2′-hexamethylene-bis- (2-oxazoline), 2,2′-octamethylene-bis- (2-oxazoline), 2,2′-ethylene-bis- (4,4 ′) Dimethyl-2-oxazoline), 2,2'-p-phenylene-bis- (2-oxazoline), 2,2'-m-phenylene-bis- (2-oxazoline), 2,2'-m-phenylene- Examples thereof include bis- (4,4′-dimethyl-2-oxazoline), bis- (2-oxazolinylcyclohexane) sulfide, and bis- (2-oxazolinyl norbornane) sulfide. Furthermore, (co) polymers of these compounds can also be preferably used.
As commercially available products, Epocross WS-700, Epocross K-2020E (both manufactured by Nippon Shokubai Co., Ltd.) and the like can be used.

The content of the crosslinking agent in the polymer layer is preferably 0.5% by mass or more and 100% by mass or less, more preferably 0.5% by mass or more and 50% by mass or less, and still more preferably 5.0% by mass with respect to the binder. The mass is 30% by mass or more. When the content of the crosslinking agent is 0.5% by mass or more, a sufficient crosslinking effect is obtained while maintaining the strength and adhesiveness of the polymer layer, and when it is 40% by mass or less, particularly 30% by mass or less, The pot life of the liquid when the coating liquid for forming the polymer layer is adjusted can be kept longer.

(Pigment)
The coating liquid used for forming the polymer layer in the present invention may contain a pigment, and the polymer layer may be formed as a colored layer. In this case, the same pigment as in the colored layer described later can be used, and the preferred embodiment is also the same. For example, a pigment having a desired hue may be included to give design properties, or a white pigment may be included to give the polymer layer a function as a reflective layer.

(Other additives)
The coating liquid for forming the polymer layer may contain other additives such as a surfactant and a filler as necessary.

Examples of the surfactant include anionic and nonionic (for example, polyoxyalkylene having 2 or 3 carbon atoms and an alkyl group having 1 to 30, preferably 2 to 24, more preferably 6 to 24 carbon atoms). Known surfactants such as alkylene alkyl ethers can be used. When the surfactant is contained, the range of the content in the polymer layer is 0.1 mg / m ² or more, and when the layer is formed, a good layer can be obtained while suppressing the occurrence of repelling. When it is m ² or less, it is possible to maintain the adhesion between the polymer support and the second polymer layer satisfactorily.

As the filler, a known filler (inorganic fine particles) such as titanium dioxide can be used. When the filler is contained, the content of the filler in the polymer layer is preferably 200% by mass or less, more preferably 150% by mass or less based on the amount of the binder in the polymer layer. When the content of the filler is 200% by mass or less, the film surface shape of the coating film can be kept better. The lower limit of the filler content is preferably 0.5% by mass. When the filler content is 200% by mass or less, it is advantageous in that a good surface shape can be obtained. Moreover, the adhesiveness after wet heat aging is favorable in content of a filler being 0.5 mass% or more. The content of the inorganic fine particles is more preferably in the range of 1% by mass to 15% by mass.

-Protective polymer layer-
In the polymer layer forming step in the present invention, two or more polymer layers can be laminated. Specifically, after forming the first polymer layer containing the compound represented by the general formula (1), the binder polymer, and other components as necessary, as the first layer on the support, As the second layer on the first polymer layer, it further contains one or more binder polymers and optionally other components such as a surfactant and a crosslinking agent. An embodiment having a second polymer layer (hereinafter also referred to as “protective polymer layer”) in which the content of the represented compound is 1.0% by mass or less with respect to the total amount of the binder polymer is also preferable. The protective polymer layer preferably further has a total content of the compound represented by the general formula (1) and other ultraviolet absorbers of 1.0% by mass or less based on the total amount of the binder polymer.

A polymer layer containing a large amount of an ultraviolet absorber by having a laminated structure in which the polymer layer mainly containing an ultraviolet absorber (including a compound represented by the general formula (1)) is protected by a protective polymer layer. As compared with the case where the surface layer is included, the absorption of ultraviolet rays is more stable, and it is possible to suppress deterioration that appears as cracks or peeling of the support over a long period of time.

The protective polymer layer may contain an ultraviolet absorber (including the compound represented by the general formula (1)) to the extent that the effects of the present invention are not impaired, but the compound represented by the general formula (1). It is preferable that the content of the UV absorber, and hence the content of the UV absorber, is 1.0% by mass or less of the total binder mass, and the protective polymer layer does not substantially contain the UV absorber and does not contain the UV absorber (0 (Mass%) is more preferable. The content of the ultraviolet absorber of 1% by mass or less of the total binder mass means that the ultraviolet absorber is not actively contained, although the inclusion of the ultraviolet absorber is not excluded at all.

Examples of the binder polymer contained in the protective polymer layer include known polymers such as a fluorine polymer, a silicone polymer, a polyester polymer, a polyurethane polymer, an acrylic polymer, and a polyolefin polymer. Can be used. Details and preferred embodiments of specific examples and the like of the polymer are as described in the polymer layer.
Among these, from the viewpoint of further improving the durability performance when exposed to changes in temperature and humidity and high humidity and heat environment, it may contain one or more selected from the group consisting of fluorine-based polymers and silicone-based polymers. preferable.

The content of the binder polymer in the protective polymer layer is preferably 50% by mass to 95% by mass, and more preferably 60% by mass to 90% by mass with respect to the total mass of the protective polymer layer. When the content of the polymer is 50% by mass or more, good durability is obtained, and when it is 95% by mass or less, the amount of the crosslinking agent and the surfactant can be secured. Is advantageous.

It is preferable that the protective polymer layer further contains at least one crosslinking agent for crosslinking the binder polymer. Examples of the crosslinking agent include epoxy-based, isocyanate-based, melamine-based, carbodiimide-based, and oxazoline-based crosslinking agents. Among these, a carbodiimide-based crosslinking agent and an oxazoline-based crosslinking agent are preferable, and a carbodiimide-based crosslinking agent is more preferable from the viewpoint of securing adhesiveness after wet heat aging.
The details of the crosslinking agent, particularly the details and preferred embodiments of the carbodiimide-based crosslinking agent and the oxazoline-based crosslinking agent are as described in the polymer layer.

The content of the crosslinking agent in the protective polymer layer is preferably 0.5% by mass or more and 40% by mass or less, and more preferably 0.5% by mass or more and 30% by mass or less with respect to the binder polymer constituting the layer. When the content of the crosslinking agent is 0.5% by mass or more, a sufficient crosslinking effect is obtained while maintaining the strength and adhesiveness of the polymer layer, and when it is 40% by mass or less, particularly 30% by mass or less, The pot life of the liquid when the coating liquid for forming the polymer layer is adjusted can be kept longer.

The protective polymer layer may further contain other additives such as a surfactant and a filler (inorganic fine particles) as necessary. These details are as described above.

The thickness of the protective polymer layer is preferably 0.5 to 12 μm. When the thickness of the protective polymer layer is 0.5 μm or more, higher durability can be obtained, and when it is 12 μm or less, the surface shape is good and the adhesiveness to the adjacent layer is excellent. The thickness of the protective polymer layer is more preferably 1.0 to 10 μm.

The protective polymer layer can be formed by preparing a coating solution containing a binder polymer or the like, applying the coating solution on the first polymer layer, and drying the coating solution. After drying, it may be cured by heating. There is no restriction | limiting in particular in the coating method and the solvent of the coating liquid to be used. As a coating method, for example, a gravure coater or a bar coater can be used. The solvent used for the preparation of the coating solution can be selected from one or more of water and organic solvents such as toluene and methyl ethyl ketone. The protective polymer layer is preferably formed by a method in which an aqueous coating solution in which a polymer is dispersed in water is prepared and applied. In this case, the proportion of water in the solvent is preferably 60% by mass or more, and more preferably 80% by mass or more.

In addition to the above, the resin film of the present invention may have other layers such as a colored layer as necessary. In this case, for example, it can be configured as a solar cell backsheet in which a polymer layer is provided on one of the supports and a colored layer (particularly a light reflecting layer) is provided on the other.

-Colored layer-
In the resin film of the present invention, a colored layer may be provided on one side of the support. In this case, it can apply as a back sheet for solar cells as an example of the resin film of this invention. As a specific example of a solar cell backsheet, a colored layer is provided on the light-receiving side of the support (the side facing the battery-side substrate provided with the solar cell element), and the back side is protected on the side opposite to the side provided with the colored layer. A mode in which the above-described polymer layer in the present invention is provided as a layer is preferable.

The colored layer in the present invention contains at least a pigment and a binder, and may further include other components such as various additives as necessary.

When the resin film of the present invention is used as a back sheet for solar cells, as a function of the colored layer, first, the light that has passed through the solar cells and reaches the back sheet without being used for power generation among the incident light. Increasing the power generation efficiency of the solar cell module by reflecting it back to the solar cell, and secondly, the decorativeness of the appearance when the solar cell module is viewed from the side where sunlight enters (front side) And so on. In general, when the solar cell module is viewed from the front side (glass substrate side), the back sheet is visible around the solar cell, and by providing a colored layer on the back sheet, the decorativeness of the back sheet itself is improved. The appearance can be improved.

(Pigment)
The colored layer can contain at least one pigment.
Examples of the pigment include inorganic pigments such as titanium dioxide, barium sulfate, silicon oxide, aluminum oxide, magnesium oxide, calcium carbonate, kaolin, talc, ultramarine blue, bitumen, and carbon black, and organic pigments such as phthalocyanine blue and phthalocyanine green. It can be appropriately selected and contained.

When the colored layer is configured as a reflective layer that reflects light that has entered the solar cell and passed through the solar cell and returns it to the solar cell, it is preferable to include white inorganic particles. As the white inorganic particles, white pigments such as titanium dioxide, barium sulfate, silicon oxide, aluminum oxide, magnesium oxide, calcium carbonate, kaolin and talc are preferable. Of these, titanium dioxide is preferable.

When the reflective layer is formed, the content of the white inorganic particles in the reflective layer is preferably in the range of 30% by mass to 90% by mass with respect to the total mass of the binder polymer and the white inorganic particles, and more preferably white inorganic particles. The range of the content of is 50 to 85% by mass. When the content of the white inorganic particles in the reflective layer is 30% by mass or more, a good reflectance is obtained, and when the content is 90% by mass or less, the back sheet for solar cells can be reduced in weight.

The content of the pigment in the colored layer is preferably in the range of 2.5 to 12 g / m ² , and more preferably in the range of 2.5 to 8.5 g / m ² . When the pigment content is 2.5 g / m ² or more, necessary coloring can be obtained, and reflectance and decorative properties can be effectively provided. In addition, when the content of the pigment in the colored layer is 12 g / m ² or less, the planar shape of the colored layer is easily maintained and the film strength is excellent.

When the colored layer is provided as a reflective layer, the reflective layer preferably contains white inorganic particles in the range of 4 to 12 g / m ² . When the content of the white inorganic particles is 4 g / m ² or more, the required reflectance is easily obtained, and when the content is 12 g / m ² or less, the weight of the back sheet can be reduced. Among these, a more preferable content of white inorganic particles in the reflective layer is in the range of 5 to 11 g / m ² .
When the reflective layer contains two or more types of white inorganic particles, the total content of all white inorganic particles in the reflective layer is preferably in the range of 4 to 12 g / m ² .

The average particle diameter of the pigment is preferably 0.03 to 0.8 μm, more preferably about 0.15 to 0.5 μm in volume average particle diameter. When the average particle size is within the above range, the light reflection efficiency is high. The volume average particle diameter is a value measured by a laser analysis / scattering particle size distribution measuring apparatus LA950 (manufactured by Horiba, Ltd.).

As the binder constituting the colored layer, a polyester resin, a polyurethane resin, an acrylic resin, a polyolefin resin, a silicone resin, or the like can be used. Among these, acrylic resin and polyolefin resin are preferable from the viewpoint of ensuring high adhesiveness. Also. Composite resins may be used, for example acrylic / silicone composite resins are also preferred binders.
The content of the binder component is preferably in the range of 15 to 200% by mass and more preferably in the range of 17 to 100% by mass with respect to the pigment. When the content of the binder is 15% by mass or more, the strength of the colored layer is sufficiently obtained, and when it is 200% by mass or less, the reflectance and the decorativeness can be kept good.

(Additive)
You may add a crosslinking agent, surfactant, a filler, etc. to a colored layer as needed.
Examples of the crosslinking agent include epoxy-based, isocyanate-based, melamine-based, carbodiimide-based, and oxazoline-based crosslinking agents. Details of the crosslinking agent, particularly details and preferred embodiments of the carbodiimide-based crosslinking agent and oxazoline-based crosslinking agent, are as described in the first polymer layer. The addition amount of the crosslinking agent is preferably 5 to 50% by mass, more preferably 10 to 40% by mass, based on the binder in the layer.

As the surfactant, known surfactants such as anionic and nonionic surfactants can be used. The details and preferred embodiments of the surfactant are as described in the first polymer layer. When the surfactant is contained, the content is preferably 0.1 to 15 mg / m ² , more preferably 0.5 to 5 mg / m ² .

As the filler, known fillers such as colloidal silica and titanium dioxide can be used. The content of the filler is preferably 20% by mass or less, more preferably 15% by mass or less per binder of the colored layer.

The colored layer can be formed by a method in which a polymer sheet containing a pigment is bonded to a support, a method in which a colored layer is co-extruded during substrate formation, a method by coating, or the like. Specifically, the colored layer can be formed by bonding, co-extrusion, coating or the like directly on the surface of the support or through an undercoat layer having a thickness of 2 μm or less. The formed colored layer may be in a state of being in direct contact with the surface of the support or in a state of being laminated via an undercoat layer.
Among the methods described above, the method by coating is preferable because it is simple and can be formed in a thin film with uniformity.

In the case of coating, a known coating method such as a gravure coater or a bar coater can be used as the coating method. The coating solution may be an aqueous system using water as an application solvent, or a solvent system using an organic solvent such as toluene or methyl ethyl ketone. Among these, from the viewpoint of environmental burden, it is preferable to use water as a solvent. A coating solvent may be used individually by 1 type, and may mix and use 2 or more types. Specifically, for example, when a reflective layer is formed, white inorganic particles, a binder, and other components are included as necessary on the surface of the polymer support on which the first and second polymer layers are not formed. It can form by apply | coating the coating liquid for reflection layer formation containing a component.

-Easy adhesion layer-
In the resin film of the present invention, an easy-adhesive layer that is easily adhesive to the organic component may be provided on one side of the support. The resin film of the present invention may be, for example, a solar cell backsheet in which an easy-adhesion layer is provided (particularly on the colored layer). In this case, the easy-adhesion layer is a layer for easily adhering firmly to the sealing material that seals the solar cell element of the battery side substrate (battery body) provided with the solar cell element.

The easy-adhesion layer can be formed using a binder and inorganic fine particles, and may further include other components such as additives as necessary. The easy-adhesion layer is used for a sealing material (for example, ethylene-vinyl acetate (EVA; ethylene-vinyl acetate copolymer), polyvinyl butyral (PVB), epoxy resin, etc.) that seals the power generation element of the battery side substrate. It is preferably configured to have an adhesive force of 10 N / cm or more (preferably 20 N / cm or more). When the adhesive force is 10 N / cm or more, it is easy to obtain wet heat resistance capable of maintaining adhesiveness.
The adhesive strength can be adjusted by a method of adjusting the amount of the binder and inorganic fine particles in the easy-adhesive layer, a method of applying a corona treatment to the surface of the back sheet that adheres to the sealing material, and the like.

(binder)
The easy-adhesion layer can contain at least one binder.
Examples of the binder suitable for the easy-adhesive layer include polyester, polyurethane, acrylic resin, polyolefin, and the like. Among these, acrylic resin and polyolefin are preferable from the viewpoint of durability. As the acrylic resin, a composite resin of acrylic and silicone is also preferable.

Examples of preferred binders include Chemipearl S-120 and S-75N (both manufactured by Mitsui Chemicals) as specific examples of polyolefins, and Jurimer ET-410 and SEK-301 (both Nippon Pure Chemical (both manufactured by Mitsui Chemicals, Inc.)). As a specific example of the composite resin of acrylic and silicone, Ceranate WSA1060, WSA1070 (both manufactured by DIC Corporation) and H7620, H7630, H7650 (both manufactured by Asahi Kasei Chemicals Corporation) and the like can be given.

The content of the binder in the easy-adhesive layer is preferably in the range of 0.05 to 5 g / m ² . In particular, the range of 0.08 to 3 g / m ² is more preferable. The content of the binder, 0.05 g / m ² or more is desired as easy adhesion obtained to that, better surface state is obtained when the is 5 g / m ² or less.

(Inorganic fine particles)
The easily adhesive layer can contain at least one kind of inorganic fine particles.
Examples of the inorganic fine particles include silica, calcium carbonate, magnesium oxide, magnesium carbonate, and tin oxide. Among these, fine particles of tin oxide and silica are preferable in that the decrease in adhesiveness when exposed to a humid heat atmosphere is small.

The particle size of the inorganic fine particles is preferably about 10 to 700 nm, more preferably about 20 to 300 nm in terms of volume average particle size. When the particle size is within this range, better easy adhesion can be obtained. The particle size is a value measured by a laser analysis / scattering particle size distribution measuring apparatus LA950 (manufactured by Horiba, Ltd.).

The shape of the inorganic fine particles is not particularly limited, and any shape such as a spherical shape, an irregular shape, or a needle shape can be used.

The content of the inorganic fine particles is preferably in the range of 5 to 400% by mass with respect to the binder in the easy-adhesive layer. When the content of the inorganic fine particles is 5% by mass or more, good adhesiveness can be maintained when exposed to a moist heat atmosphere, and when it is 400% by mass or less, the surface state of the easily adhesive layer is good. . In particular, the content of inorganic fine particles is preferably in the range of 50 to 300% by mass.

(Crosslinking agent)
The easily adhesive layer can contain at least one crosslinking agent.
Examples of the crosslinking agent suitable for the easily adhesive layer include epoxy-based, isocyanate-based, melamine-based, carbodiimide-based, and oxazoline-based crosslinking agents. Among these, an oxazoline-based cross-linking agent is particularly preferable from the viewpoint of ensuring adhesiveness after wet heat aging.
Details of the crosslinking agent, particularly details and preferred embodiments of the carbodiimide-based crosslinking agent and oxazoline-based crosslinking agent, are as described in the first polymer layer. Moreover, as a commercially available product having an oxazoline group, Epocros K2010E, K2020E, K2030E, WS-500, WS-700 (all manufactured by Nippon Shokubai Co., Ltd.), etc. can be used. It is.

The content of the crosslinking agent in the easy-adhesive layer is preferably 5 to 50% by mass, more preferably 20 to 40% by mass, based on the binder in the easy-adhesive layer. When the content of the crosslinking agent is 5% by mass or more, a good crosslinking effect can be obtained, and the strength and adhesiveness of the colored layer can be maintained. When the content is 50% by mass or less, the pot life of the coating liquid Can be kept long.

(Additive)
If necessary, the easily adhesive layer may further contain a known matting agent such as polystyrene, polymethylmethacrylate, or silica, or a known surfactant such as anionic or nonionic.

The formation of the easy-adhesion layer includes a method of bonding a polymer sheet having easy adhesion to a support or a method by coating. Especially, the method by application | coating is preferable at the point which is easy and can form in a thin film with uniformity. As a coating method, for example, a known coating method such as a gravure coater or a bar coater can be used. The coating solvent used for preparing the coating solution may be water or an organic solvent such as toluene or methyl ethyl ketone. A coating solvent may be used individually by 1 type, and may mix and use 2 or more types.

The thickness of the easy-adhesion layer is not particularly limited, but is usually preferably 0.05 to 8 μm, more preferably 0.1 to 5 μm. When the thickness of the easy-adhesion layer is 0.05 μm or more, necessary easy adhesion can be suitably obtained, and when it is 8 μm or less, the surface shape becomes better.
In addition, the easily adhesive layer of the present invention needs to be transparent so as not to reduce the effect of the colored layer.

-Support-
The resin film of the present invention is configured by providing a support. As the support, a conventionally known support substrate can be appropriately selected.

From the viewpoint of further enhancing the effect of improving light resistance by using a specific ultraviolet absorber in the polymer layer, a polymer substrate is preferred. Examples of the polymer base material include base materials using polyester, polyolefins such as polypropylene and polyethylene, or fluorine-based polymers such as polyvinyl fluoride. Among these, a polyester base material is preferable from the viewpoint of cost and mechanical strength.

The polyester used as the support in the present invention is a linear saturated polyester synthesized from an aromatic dibasic acid or an ester-forming derivative thereof and a diol or an ester-forming derivative thereof. Specific examples of such polyester include polyethylene terephthalate, polyethylene isophthalate, polybutylene terephthalate, poly (1,4-cyclohexylenedimethylene terephthalate), polyethylene-2,6-naphthalate and the like. Of these, polyethylene terephthalate or polyethylene-2,6-naphthalate is particularly preferable from the viewpoint of balance between mechanical properties and cost.

The polyester may be a homopolymer or a copolymer. Further, the polyester may be blended with a small amount of another type of resin such as polyimide.

When polymerizing the polyester in the present invention, it is preferable to use an Sb-based, Ge-based or Ti-based compound as a catalyst from the viewpoint of keeping the carboxyl group content below a predetermined range, and among these, a Ti-based compound is particularly preferable. In the case of using a Ti-based compound, an embodiment is preferred in which the Ti-based compound is polymerized by using it as a catalyst so that the Ti element conversion value is in the range of 1 ppm to 30 ppm, more preferably 3 ppm to 15 ppm. When the amount of Ti compound used is within the above range in terms of Ti element, the terminal carboxyl group can be adjusted to the following range, and the hydrolysis resistance of the polymer substrate can be kept low.

Examples of the synthesis of polyester using a Ti compound include Japanese Patent Publication No. 8-301198, Japanese Patent No. 2543624, Japanese Patent No. 3335683, Japanese Patent No. 3717380, Japanese Patent No. 397756, Japanese Patent No. 39622626, and Japanese Patent No. 39786666. No. 3, Patent No. 3,996,871, Patent No. 40000867, Patent No. 4053837, Patent No. 4,127,119, Patent No. 4,134,710, Patent No. 4,159,154, Patent No. 4,269,704, Patent No. 4,313,538 and the like can be applied.

The carboxyl group content in the polyester is preferably 50 equivalents / t or less, more preferably 35 equivalents / t or less. When the carboxyl group content is 50 equivalents / t or less, hydrolysis resistance can be maintained, and a decrease in strength when subjected to wet heat aging can be suppressed to be small. The lower limit of the carboxyl group content is preferably 2 equivalents / t in terms of maintaining adhesion between the layer formed on the polyester (for example, a colored layer).
The carboxyl group content in the polyester can be adjusted by the polymerization catalyst species and the film forming conditions (film forming temperature and time). In the present specification, “equivalent / ton” represents a molar equivalent per ton.

The polyester in the present invention is preferably solid-phase polymerized after polymerization. Thereby, a preferable carboxyl group content can be achieved. Solid-phase polymerization may be a continuous method (a method in which a tower is filled with a resin, which is slowly heated for a predetermined time and then sent out), or a batch method (a resin is charged into a container). , A method of heating for a predetermined time). Specifically, for solid phase polymerization, Japanese Patent No. 2621563, Japanese Patent No. 3121876, Japanese Patent No. 3136774, Japanese Patent No. 3603585, Japanese Patent No. 3616522, Japanese Patent No. 3617340, Japanese Patent No. 3680523, Japanese Patent No. 3717392 are disclosed. The method described in Japanese Patent No. 4167159 can be applied.

The temperature of the solid phase polymerization is preferably 170 ° C. or higher and 240 ° C. or lower, more preferably 180 ° C. or higher and 230 ° C. or lower, and further preferably 190 ° C. or higher and 220 ° C. or lower. The solid phase polymerization time is preferably 5 hours to 100 hours, more preferably 10 hours to 75 hours, and still more preferably 15 hours to 50 hours. The solid phase polymerization is preferably performed in a vacuum or in a nitrogen atmosphere.

For example, the polyester base material in the present invention is obtained by melt-extruding the above polyester into a film shape and then cooling and solidifying it with a casting drum to form an unstretched film. The unstretched film is subjected to a longitudinal direction at Tg to (Tg + 60) ° C. A biaxially stretched film that has been stretched once or twice or so so that the total magnification is 3 to 6 times, and then stretched so that the magnification is 3 to 5 times in the width direction at Tg to (Tg + 60) ° C. Preferably there is.
Further, heat treatment may be performed at 180 to 230 ° C. for 1 to 60 seconds as necessary. Tg represents a glass transition temperature and can be measured based on JIS K7121 or ASTM D3418-82. For example. In the present invention, measurement is performed using a differential scanning calorimeter (DSC) manufactured by Shimadzu Corporation.
Specifically, 10 mg of a polymer such as polyester is weighed as a sample, set in an aluminum pan, and heated at a rate of temperature increase of 10 ° C./min from room temperature to a final temperature of 300 ° C., with a DSC device, the amount of heat relative to temperature Was measured as the glass transition temperature.

The thickness of the polymer substrate (particularly the polyester substrate) is preferably about 25 to 300 μm. If the thickness is 25 μm or more, the mechanical strength is good, and if it is 300 μm or less, it is advantageous in terms of cost.
In particular, the polyester base material has a tendency to deteriorate the hydrolysis resistance as the thickness increases and cannot withstand long-term use. In the present invention, the thickness of the polyester base material is 120 μm or more and 300 μm or less, and When the content of the carboxyl group in the polyester is 2 to 50 equivalent / t, the effect of improving the wet heat durability is further exhibited.

-Production of resin film-
The resin film of the present invention is configured by providing a polymer layer forming step as described above. As a specific manufacturing method, for example,
(1) adding and emulsifying and dispersing an oil phase containing the compound represented by the general formula (1) in an aqueous phase containing a water-soluble resin (eg, PVA);
(2) Contains an emulsion obtained by the above emulsification dispersion, a fluorine-based polymer and / or a silicone-based polymer, and, if necessary, a crosslinking agent or a surfactant, and preferably 50% by mass or more of the solvent is water. A step of preparing a coating solution;
(3) a step of applying the coating solution directly or via another layer to at least one surface of the polymer substrate (support);
(4) a step of drying the coating film formed on the polymer substrate to form a polymer layer;
Can be provided.
Here, after forming the polymer layer, the adhesiveness after wet heat aging can be enhanced by curing the polymer layer.
As described above, when another layer such as an easy-adhesive layer is provided, a step for forming another layer can be further provided in addition to the above step. As an example of the formation mode of the other layer, for example, a coating liquid containing the components constituting the other layer is applied on the polymer substrate (for example, the side opposite to the side on which the polymer layer of the polymer substrate is formed). The method of apply | coating is mentioned. Examples thereof include the methods described above as the method for forming the easily adhesive layer and the colored layer.

The resin film of this invention is used suitably for the use of the solar cell backsheet.
Specific examples of solar cell backsheets include: (1) A reflection containing a polymer layer on one side of a polymer substrate and a white pigment on the other side opposite to the side on which the polymer layer is coated (2) A polymer layer is coated on one side of the polymer substrate, and the other side opposite to the side on which the polymer layer is coated is colored The thing etc. which the colored layer containing a pigment was coated can be mentioned.
Moreover, as an example of other formation modes, such as a reflective layer and an easily-adhesive layer, the polymer layer of the polymer base material is not coated with a sheet or film having one or more layers having a desired function. The method of bonding to the other side (formation surface) is mentioned. The sheet or film in this case is a sheet or film having one or more other layers. Specifically, a polymer layer is applied and formed on one side of a polymer substrate, and a white pigment (or a colored pigment other than white) is formed on the other side opposite to the side on which the polymer layer is formed. A white film (or a colored film) containing a polymer, a white film containing an aluminum thin film and a white pigment on the other side, and a polymer having an inorganic barrier layer on the other side. What stuck the white film containing a film and a white pigment, etc. are mentioned.

Moreover, when the polymer support used as a support is a biaxially stretched film, a coating solution for forming a polymer layer may be applied to the polymer substrate after biaxial stretching, or the polymer after uniaxial stretching After the coating liquid for forming the polymer layer is applied to the substrate and dried, it may be stretched in a direction different from the direction of uniaxial stretching. Further, the coating solution may be applied to an unstretched polymer support and dried, and then stretched in two directions.

Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples as long as the gist thereof is not exceeded. Unless otherwise specified, “part” is based on mass.

Example 1
-Fabrication of support-
(1) Synthesis of polyester A slurry of 100 kg of high-purity terephthalic acid (manufactured by Mitsui Chemicals) and 45 kg of ethylene glycol (manufactured by Nippon Shokubai Co., Ltd.) was charged with about 123 kg of bis (hydroxyethyl) terephthalate in advance and the temperature was 250 The esterification reaction tank maintained at a temperature of 1.2 ° C. and a pressure of 1.2 × 10 ⁵ Pa was sequentially supplied over 4 hours, and the esterification reaction was carried out over an additional hour after the completion of the supply. Thereafter, 123 kg of the obtained esterification reaction product was transferred to a polycondensation reaction tank.

Subsequently, 0.3% by mass of ethylene glycol was added to the resulting polymer in the polycondensation reaction tank to which the esterification reaction product had been transferred. After stirring for 5 minutes, an ethylene glycol solution of cobalt acetate and manganese acetate was added to the obtained polymer so that the cobalt element conversion value was 30 ppm and the manganese element conversion value was 15 ppm. After further stirring for 5 minutes, a 2% by mass ethylene glycol solution of a titanium alkoxide compound was added to the obtained polymer so that the titanium element equivalent value was 5 ppm. As the titanium alkoxide compound, the titanium alkoxide compound (Ti content = 4.44 mass%) synthesized in Example 1 of paragraph No. [0083] of JP-A-2005-340616 was used. Five minutes later, a 10% by mass ethylene glycol solution of ethyl diethylphosphonoacetate was added so as to be 5 ppm with respect to the resulting polymer.

Thereafter, while the low polymer was stirred at 30 rpm, the reaction system was gradually heated from 250 ° C. to 285 ° C. and the pressure was reduced to 40 Pa. The time to reach the final temperature and final pressure was both 60 minutes. The reaction was continued for 3 hours, and then the reaction system was purged with nitrogen and returned to normal pressure to stop the polycondensation reaction. Then, the obtained polymer melt was discharged into cold water in a strand form and immediately cut to produce polymer pellets (diameter: about 3 mm, length: about 7 mm).

(2) Solid phase polymerization The pellets obtained above were held in a vacuum vessel maintained at 40 Pa at a temperature of 220 ° C for 30 hours to perform solid phase polymerization.

(3) Base formation The pellets after undergoing solid-phase polymerization as described above were melt-extruded at 280 ° C. and cast on a metal drum to produce an unstretched base having a thickness of about 2.5 mm. Thereafter, the film was stretched 3 times in the longitudinal direction at 90 ° C., and further stretched 3.3 times in the transverse direction at 120 ° C. Furthermore, heat setting was performed at 215 ° C. for 1 minute to obtain a biaxially stretched polyethylene terephthalate support (hereinafter simply referred to as “PET support”) having a thickness of 250 μm.

-Undercoat layer-
(1) Preparation of coating solution for forming undercoat layer Each component in the following composition was mixed to prepare a coating solution for forming an undercoat layer.
<Composition of coating solution>
・ Polyester binder: 48.0 parts
(Byronal DM1245, manufactured by Toyobo Co., Ltd., solid content: 30% by mass)
Carbodiimide compound (crosslinking agent) 10.0 parts (Carbodilite V-02-L2, manufactured by Nisshinbo Industries, Ltd., solid content: 10% by mass)
Oxazoline compound (crosslinking agent) 3.0 parts (Epocross WS700, manufactured by Nippon Shokubai Co., Ltd., solid content: 25% by mass)
Surfactant: 15.0 parts (Naroacty CL95, manufactured by Sanyo Chemical Industries, solid content: 1% by mass)
・ Distilled water ... 924.0 parts

(2) Formation of undercoat layer The obtained undercoat layer-forming coating solution was applied to one surface of a PET support so that the amount of the binder was 0.1 g / m ² and applied at 180 ° C for 1 minute. An undercoat layer having a dry thickness of about 0.1 μm was formed by drying.

-Colored layer-
(1) Preparation of Titanium Dioxide Dispersion Components in the following composition were mixed, and the mixture was subjected to dispersion treatment for 1 hour using a dynomill type disperser.
<Composition of titanium dioxide dispersion>
・ Titanium dioxide (volume average particle size = 0.42 μm) 39.9% by mass
(Taipeke R-780-2, manufactured by Ishihara Sangyo Co., Ltd., solid content 100% by mass)
・ Polyvinyl alcohol: 49.9% by mass
(PVA-105, manufactured by Kuraray Co., Ltd., solid content: 10% by mass)
・ Surfactant ... 0.5% by mass
(Demol EP, manufactured by Kao Corporation, solid content: 10% by mass)
・ Distilled water: 9.7% by mass

(2) Preparation of colored layer coating solution Components in the following composition were mixed to prepare a colored layer coating solution.
<Composition of coating solution>
・ Titanium dioxide dispersion: 800.0 parts ・ Polyolefin binder: 108.0 parts (Arrow Base SE1010, manufactured by Unitika Ltd., solid content: 20% by mass)
Polyoxyalkylene alkyl ether 30.0 parts (Naroacty CL95, manufactured by Sanyo Chemical Industries, solid content: 1% by mass)
Oxazoline compound: 20.0 parts (Epocross WS-700, manufactured by Nippon Shokubai Co., Ltd., solid content: 25%; crosslinking agent)
・ Distilled water ... 42.0 parts

(3) Formation of colored layer The obtained coating solution is applied on the undercoat layer formed on the PET support and dried at 180 ° C. for 1 minute, and the amount of titanium dioxide is 8. A reflective layer having 0 g / m ² and a binder amount of 1.5 g / m ² was formed.

-Back layer 1-
(1) Preparation of Dispersion of Compound (A) In a mixed solvent obtained by mixing 35.4 g of ethyl acetate and 8.8 g of tetrahydrofuran, the following compound (A-1) (represented by the general formula (1) described above) Compound (18.9 g) was added, heated to 50 ° C. and stirred for 10 minutes to prepare an oil phase solution in which compound (A-1) was dissolved.

Subsequently, 112 g of distilled water was added to a 400 cc stainless steel container and heated to 90 ° C., and then 16 g of Kuraray Poval PVA-205 (polyvinyl alcohol, manufactured by Kuraray Co., Ltd.) was added and dissolved by stirring at 90 ° C. for 3 hours. To prepare an aqueous phase solution.

Subsequently, the oil phase liquid was added while stirring the obtained aqueous phase liquid at 500 rpm using a dissolver. After the addition, stirring was continued for another 5 minutes to obtain a uniform mixed solution. The resulting mixed liquid (25 ° C.) was further stirred using a dissolver at 20,000 rpm for 10 minutes at 25 ° C. to obtain an emulsion (emulsion) 1. The average particle size of the obtained emulsion 1 was measured by a laser analysis / scattering particle size distribution measuring apparatus LA950 (manufactured by Horiba, Ltd.), and the median size was 120 nm.

The organic solvent was distilled off from the emulsion 1 using an evaporator to obtain a dispersion 1. The amount of the remaining organic solvent was measured by gas chromatography and found to be 0.7% by mass or less. The concentration of Compound A-1 in Dispersion 1 was 13% by mass. When the average particle diameter of Dispersion 1 was measured by the same method as described above, the median diameter was 121 nm.

(2) Preparation of coating solution for forming back layer 1 Each component in the following composition was mixed to prepare a coating solution for forming back layer 1.
<Composition of coating solution>
Acrylic / silicone binder (Binder B-1) 400.0 parts (Ceranate WSA-1070, manufactured by DIC Corporation, solid content: 40% by mass)
-Carbodiimide compound (crosslinking agent) 48.0 parts (Carbodilite V-02-L2, manufactured by Nisshinbo Co., Ltd., solid content: 40% by mass)
Surfactant: 9.8 parts (Naroacty CL95, manufactured by Sanyo Chemical Industries, solid content: 1% by mass)
-Dispersion of the compound A-1 428.6 parts (content ratio of the compound A-1 = 14% by mass)
・ Distilled water ... 113.6 parts

(3) Formation of Back Layer 1 The obtained coating solution for forming the back layer 1 is coated with a binder coating amount of 3.0 g / m ² on the support surface opposite to the side on which the reflective layer of the PET support is formed. Then, the compound A-1 was applied in an amount of 1.1 g / m ² and dried at 180 ° C. for 1 minute to form a back layer 1 (polymer layer) having a dry thickness of about 3 μm.

As described above, a backsheet sample in which each layer was formed by coating on both sides of a PET support was produced.

-Fabrication of solar cell module-
A tempered glass having a thickness of 3 mm, an EVA sheet [SC50B, manufactured by Mitsui Chemicals, Inc.], a crystalline solar cell, and an EVA sheet [SC50B, manufactured by Mitsui Chemicals, Inc.], manufactured as described above. The back sheet samples after the same treatment as “(B) Adhesion after wet heat aging” in the following evaluation “4. Adhesiveness” were stacked in this order, and a vacuum laminator [manufactured by Nisshinbo Co., Ltd., vacuum It was bonded by hot pressing using a laminating machine. However, the back sheet sample was arranged so that the surface of the colored layer was in contact with the EVA sheet. Adhesion was performed under the condition that a vacuum laminator was evacuated at 128 ° C. for 3 minutes, then pressure-bonded for 2 minutes to perform temporary adhesion, and further in a dry oven at 150 ° C. for 30 minutes. In this way, a crystalline solar cell module was produced.
When power generation operation was performed using the produced solar cell module, it showed good power generation performance as a solar cell.

(Examples 2 to 10)
In Example 1, a backsheet sample was prepared and evaluated in the same manner as in Example 1 except that the concentration and coating amount of Compound A-1, and the binder concentration were changed as shown in Table 1 below. A battery module was produced. The evaluation results are shown in Table 1 below.

(Examples 11 to 14, Comparative Examples 1 to 3)
In Example 8, except that the compound A-1 used for the preparation of the coating solution for forming the back layer 1 was changed to the following compounds A-2 to A-5 and A-101 to A-103. In the same manner as in Example 8, a backsheet sample was prepared and evaluated, and a solar cell module was prepared. The evaluation results are shown in Table 1 below.

(Example 15)
In Example 8, on the surface of the back layer 1 (polymer layer) formed on the surface opposite to the side on which the reflective layer of the PET support is provided, the back layer 2 forming application is performed according to the following procedure. A backsheet sample was prepared and evaluated in the same manner as in Example 8 except that the back layer 2 (protective polymer layer) was further formed by applying the liquid, and a solar cell module was prepared. The evaluation results are shown in Table 1 below.

-Formation of back layer 2-
(1) Preparation of coating solution for forming back layer 2 Each component in the following composition was mixed to prepare a coating solution for forming back layer 2.
<Composition of coating solution>
Acrylic / silicone binder (Binder B-1): 362.3 parts (Ceranate WSA-1070, manufactured by DIC Corporation, solid content: 40% by mass)
Carbodiimide compound (crosslinking agent) 24.2 parts (Carbodilite V-02-L2, manufactured by Nisshinbo Co., Ltd., solid content: 40% by mass)
-Surfactant ... 24.2 parts (Naroacty CL95, manufactured by Sanyo Chemical Industries, solid content: 1% by mass)
・ Distilled water ... 589.3 parts

(2) Formation of Back Layer 2 After coating the obtained back layer 2 forming coating solution on the back layer 1 with a # 10 Meyer bar so that the binder coating amount is 2.0 g / m ² , It dried at 180 degreeC for 1 minute, and formed the back surface layer 2 with a dry thickness of about 2 micrometers as a protective polymer layer. In this way, a backsheet sample was prepared in which each layer on both sides of the PET support was provided as a coating layer by coating.

(Examples 16 to 19)
In Example 15, a backsheet sample was prepared and evaluated in the same manner as in Example 15 except that the binder type or ultraviolet absorber type of the back layer 1 was changed as shown in Table 1 below. A module was produced. The evaluation results are shown in Table 1 below.

(Evaluation)
The following evaluation was performed on the backsheet samples prepared in the above examples and comparative examples. The evaluation results are shown in Table 1 below.

-1. Light resistance
The YI value (YI-1) of each backsheet sample was measured using a spectroscopic color difference meter “Spectro Color Meter SE2000” manufactured by Nippon Denshoku Industries Co., Ltd. Thereafter, each backsheet sample was irradiated with ultraviolet light at an illuminance of 900 W / m ² for 48 hours using a light resistance tester “I Super UV Tester W-151” manufactured by Iwasaki Electric Co., Ltd. However, environmental conditions at the time of ultraviolet light irradiation were 63 ° C. and 50% RH.
Subsequently, the YI value (YI-2) of each backsheet sample was measured again using the same spectral color difference meter (Spectro Color Meter SE2000, manufactured by Nippon Denshoku Industries Co., Ltd.).
YI = (YI−2) − (YI−1) was determined from the measured values, and was used as an index indicating the degree of coloring of each backsheet sample, and was ranked according to the following evaluation criteria based on the YI value. Of these, ranks 3 to 5 are practically acceptable.
<Evaluation criteria>
5: YI value was less than 3.
4: YI value was 3 or more and less than 5.
3: YI value was 5 or more and less than 10.
2: YI value was 10 or more and less than 20.
1: YI value was 20 or more.

-2. Breaking elongation retention rate-
Each backsheet sample, based on the measured value L ⁰ and L ¹ of breaking elongation obtained by the following measurement method was calculated elongation at break retention by the following formula [%]. The range of practically acceptable breaking elongation retention is 50% or more.
Elongation at break [%] = (L ¹ / L ⁰ ) × 100
<Method for measuring elongation at break>
The back sheet sample was cut into a width of 10 mm and a length of 200 mm to prepare a sample A and a sample B for measurement. After subjecting sample A to humidity control at 25 ° C. and 60% RH for 24 hours, sample A was sandwiched between upper and lower clips with Tensilon (produced by ORIENTEC, RTC-1210A), peeling angle 180 °, pulling speed A tensile test was performed at 300 mm / min. In the tensile test, the length of the sample A to be stretched was 10 cm, and the tensile speed was 20 mm / min. The elongation at break of the sample A obtained in this study and L ^0.
Separately, the sample B was subjected to a wet heat treatment in an atmosphere of 120 ° C. and 100% RH for 50 hours, and then a tensile test was performed in the same manner as the sample A. The elongation at break of Sample B at this time is L ^1.

-3. Coating surface-
The applied surface of the backsheet sample was observed visually and with an optical microscope, and evaluated according to the following evaluation criteria. The optical microscope had a magnification of 50 times, and an area of 20 mm × 50 mm on the backsheet sample surface was observed. Note that rank 3 or higher is a practically allowable range.
<Evaluation criteria>
5: No unevenness or aggregation of the UV absorber was observed.
4: Although slight unevenness was observed, aggregation of the ultraviolet absorber could not be confirmed.
3: Unevenness was observed, but aggregation of the UV absorber could not be confirmed.
2: Unevenness was clearly confirmed, and aggregation of the UV absorber was observed to be less than 10 / m ² .
1: Unevenness was clearly confirmed, and aggregation of ultraviolet absorbers was observed at 10 pieces / m ² or more.

-4. Adhesiveness-
[A] Adhesiveness before wet heat aging Each backsheet sample was cut into a width of 20 mm × 150 mm to prepare two sample pieces. These two sample pieces are arranged so that the reflection layer side is inside, and an EVA sheet (EVA sheet manufactured by Mitsui Chemicals Fabro Co., Ltd .: SC50B) cut between 20 mm width × 100 mm length is sandwiched between them It was made to adhere to EVA by hot pressing using a laminator (vacuum laminator manufactured by Nisshinbo Co., Ltd.). The bonding conditions at this time were as follows.
Using a vacuum laminator, evacuation was performed at 128 ° C. for 3 minutes, and then pressure was applied for 2 minutes to temporarily bond. Thereafter, the main adhesion treatment was performed in a dry oven at 150 ° C. for 30 minutes. In this way, a sample for adhesion evaluation was obtained in which the 20 mm portion from one end of the two sample pieces adhered to each other was not bonded to EVA, and the EVA sheet was bonded to the remaining 100 mm portion.

The EVA non-bonded portion of the obtained sample for adhesion evaluation is sandwiched between upper and lower clips with Tensilon (ORITCTEC, RTC-1210A), and a tensile test is performed at a peeling angle of 180 ° and a pulling speed of 300 mm / min to measure the adhesive strength. did.
Based on the measured adhesive strength, ranking was performed according to the following evaluation criteria. Evaluation ranks 4 and 5 are practically acceptable ranges.
<Evaluation criteria>
5: Adhesion was very good (60 N / 20 mm or more).
4: Adhesion was good (30 N / 20 mm or more and less than 60 N / 20 mm).
3: Adhesion was slightly poor (20 N / 20 mm or more and less than 30 N / 20 mm).
2: Adhesion failure occurred (10 N / 20 mm or more and less than 20 N / 20 mm).
1: The adhesion failure was remarkable (less than 10 N / 20 mm).

[B] Adhesiveness after wet heat aging The sample for adhesion evaluation obtained above was held for 48 hours (wet heat aging) at 120 ° C. and 100% RH, and then the same method as in [A] above. The adhesive force was measured. For the measured adhesion strength after holding, the ratio of the same adhesion evaluation sample to [A] adhesion strength before wet heat aging [%; = adhesion strength after wet heat aging / [A] adhesive strength before wet heat aging × 100 ] Was calculated. Moreover, based on the measured adhesive strength after wet heat aging, the adhesive strength was evaluated by the same method as in the above [A].

As shown in Table 1, in the examples, better light resistance was exhibited as compared with the comparative example in which the compound represented by the general formula (1) was not used.

The above description of specific embodiments of the present invention is provided for purposes of description and explanation. It is not intended to limit the invention to the precise form disclosed, nor is it intended to be exhaustive. Obviously, many modifications and variations will be apparent to practitioners skilled in this art. The embodiments have been selected to best illustrate the concepts of the invention and their practical application, and thus various embodiments and methods to adapt them to specific applications contemplated by others skilled in the art. It is intended to allow others skilled in the art to understand the present invention so that various modifications can be made.

Japanese Patent Application No. 2010-274101, filed on Dec. 08, 2010, the entire disclosure of which is incorporated herein by reference.
All publications, patent applications, and technical standards mentioned in this specification are intended to be specifically and individually incorporated by reference as individual references, patent applications, and technical standards. Is incorporated herein to the same extent as the cited references. It is intended that the scope of the invention be determined by the following claims and their equivalents.

Claims

The manufacturing method of the resin layer which has a polymer layer formation process which apply | coats the coating liquid containing the compound and binder polymer which are represented by following General formula (1) at least on a support body, and forms a polymer layer.

[Wherein, R 1a , R 1b , R 1c , R 1d , and R 1e each independently represent a monovalent substituent other than a hydroxy group, and at least one of R 1a to R 1e is a Hammett's rule It represents a substituent having a σp value of 0.3 or more. The substituents represented by R 1a to R 1e may be bonded to each other to form a ring. R 1g , R 1h , R 1i , R 1j , R 1k , R 1m , R 1n , and R 1p each independently represent a hydrogen atom or a monovalent substituent, and the substituents are bonded to each other A ring may be formed. ]
In the general formula (1), R 1a , R 1c and R 1e represent a hydrogen atom, and at least one of R 1b and R 1d is an alkoxycarbonyl group, a nitro group, a cyano group, a fluoroalkyl group, a sulfonic acid or The method for producing a resin film according to claim 1, which is an alkali metal salt.
The concentration of the compound represented by the general formula (1) in the coating solution is 3% by mass to 9% by mass with respect to the total mass of the coating solution, and the concentration of the binder polymer in the coating solution. The method for producing a resin film according to claim 1, wherein the content is 6% by mass to 25% by mass with respect to the total mass of the coating solution.
And a step of preparing a dispersion by dispersing the compound represented by the general formula (1) in a solvent,
The said polymer layer formation process is a manufacturing method of the resin film of Claim 1 which apply | coats the said coating liquid in which the compound represented by the said General formula (1) contained in the dispersion state using the said dispersion liquid.
The method for producing a resin film according to claim 1, comprising a polymer selected from a fluorine-based polymer and a silicone-based polymer as at least one kind of the binder polymer.
The method for producing a resin film according to claim 1, wherein the coating liquid further contains a crosslinking agent that crosslinks the binder.
The method for producing a resin film according to claim 6, wherein the crosslinking agent is a carbodiimide crosslinking agent and / or an oxazoline crosslinking agent. *
The method for producing a resin film according to claim 6, wherein the content of the crosslinking agent in the polymer layer is 0.5% by mass or more and 40% by mass or less with respect to the binder polymer.
The method for producing a resin film according to any one of claims 1 to 6, wherein the coating liquid further contains a solvent, and 50% by mass or more of the solvent is water.
The method for producing a resin film according to any one of claims 1 to 6, wherein the support is a polyester base material.
A colored layer forming step of forming a colored layer by applying a coating solution containing at least a pigment and a binder on a support opposite to the side on which the polymer layer is formed. Item 7. The method for producing a resin film according to any one of Items 6.
The resin film according to any one of claims 1 to 6, further comprising a protective layer forming step of applying a protective layer coating solution containing at least the binder polymer on the polymer layer to form a protective layer. Production method.
7. The solar cell backsheet according to claim 1, wherein the solar cell element is used as a solar cell backsheet provided on a side opposite to a side on which solar light is incident on a battery side substrate in which a solar cell element is sealed with a sealing material. Manufacturing method of resin film.