Laminated glass interlayer, laminated glass, solar cell encapsulant, and solar cell module

Abstract

Provided is an adhesive resin composition comprising an ethylene / unsaturated ester copolymer (A) and an epoxy group-containing ethylene-based copolymer (B) (excluding the ethylene / unsaturated ester copolymer (A)), wherein the content of structural units derived from unsaturated ester in the ethylene / unsaturated ester copolymer (A) is more than 20 mass% with respect to all structural units constituting the ethylene / unsaturated ester copolymer (A), and the absolute value of the difference (X1-X2) between the content (X1) of structural units derived from ethylene with respect to all structural units constituting the ethylene / unsaturated ester copolymer (A) and the content (X2) of structural units derived from ethylene with respect to all structural units constituting the epoxy group-containing ethylene-based copolymer (B) is 10 mass% or less.

Description

Technical Field

[0001] The present invention relates to an adhesive resin composition, a laminated glass interlayer, laminated glass, a solar cell encapsulant, and a solar cell module.

Background Art

[0002] The laminated glass interlayer is installed by being sandwiched between two pieces of glass. It can prevent the fragments from scattering when the glass is damaged, or prevent the glass from collapsing due to the self-supporting property of the interlayer when the glass is cracked, and is preferably used from the viewpoint of safety.

[0003] As a material for a highly transparent laminated glass interlayer, for example, an ionomer resin is used. The ionomer resin is characterized by excellent transparency and excellent adhesiveness to glass.

[0004] For example, Patent Document 1 describes an interlayer for laminated glass characterized by being made of an ionomer resin in which a binary copolymer of (A) ethylene and (B) (meth) acrylic acid or (meth) acrylic acid acrylate is crosslinked with metal ions and having an MFR of 5 to 15 g / 10 minutes at 190°C × 2.16 Kgf. And Patent Document 1 describes that such an interlayer for laminated glass does not require a humidity control step (humidity conditioning step), and despite the simplicity of the bonding process with a glass plate, sufficient adhesiveness to the glass plate and excellent followability to the glass plate can be obtained, and excellent toughness can be maintained in a wide temperature range, and moreover, discoloration hardly occurs against direct sunlight or ultraviolet rays, and it also has excellent weather resistance and transparency.

[0005] Furthermore, Patent Document 2 describes a polymer sheet having a thickness of 10 mil (0.25 mm) or more and comprising at least one layer containing an ionomer or ionomer blend into which a partially neutralized α,β-ethylenically unsaturated carboxylic acid has been introduced, characterized in that the ionomer or ionomer blend contains one or more monovalent metal ions in an amount ranging from about 1% to about 60% based on the total amount of neutralized α,β-ethylenically unsaturated carboxylic acid, and one or more polyvalent metal ions in an amount ranging from about 40% to about 99%. Patent Document 2 also states that such a polymer sheet exhibits synergistically high adhesion to glass.

[0006] Furthermore, Patent Document 3 describes a glass laminate comprising a thin glass sheet and an ionomer intermediate layer sheet, wherein the thin glass sheet has a thickness of 1.5 mm or less. Patent Document 3 also states that such a glass laminate is lightweight and maintains advantageous performance characteristics such as good impact adhesion level, good moisture resistance, and low stress. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2013-28486 [Patent Document 2] Special Publication No. 2009-512763 [Patent Document 3] Special Publication No. 2012-519646 [Overview of the project] [Problems that the invention aims to solve]

[0008] In recent years, there has been a growing need to add decorative elements to highly transparent laminated glass by installing a decorative polyester resin layer between the glass and the laminated glass interlayer. However, while ionomers have excellent adhesion to glass, their adhesion to polyester resins is poor, making it difficult to directly laminate a layer containing ionomers (hereinafter also referred to as the "ionomer resin layer") with a polyester resin layer containing polyester resin (hereinafter also referred to as the "polyester resin layer").

[0009] One method for laminating an ionomer resin layer and a polyester resin layer is to laminate a layer containing an adhesive resin composition between the ionomer resin layer and the polyester resin layer. However, adhesive resin compositions that have high adhesion to the polyester resin layer do not have sufficient transparency, and laminating a layer containing such an adhesive resin composition between the ionomer resin layer and the polyester resin layer sometimes reduces the transparency of the laminated glass. Furthermore, since solar cell modules also utilize glass and polyester resin layers, the solar cell encapsulant used to seal the solar cell elements in the solar cell module may also require improved transparency and adhesion to the polyester resin layer. In other words, there was a need for an adhesive resin composition with improved transparency and adhesion to polyester resin layers.

[0010] The present invention has been made in view of the above circumstances, and provides an adhesive resin composition with improved transparency and adhesion to a polyester resin layer, as well as a laminated glass interlayer, laminated glass, solar cell encapsulant, and solar cell module with improved transparency, adhesion to a polyester resin layer, and adhesion to glass. [Means for solving the problem]

[0011] According to the present invention, the following adhesive resin composition, laminated glass interlayer, laminated glass, solar cell encapsulant, and solar cell module are provided.

[0012] [1] The material comprises an ethylene-unsaturated ester copolymer (A) and an epoxy group-containing ethylene copolymer (B) (excluding the ethylene-unsaturated ester copolymer (A)). The content of constituent units derived from unsaturated esters in the ethylene-unsaturated ester copolymer (A) is more than 20% by mass relative to the total constituent units of the ethylene-unsaturated ester copolymer (A). An adhesive resin composition in which the absolute value of the difference (X1-X2) between the content of ethylene-derived constituent units (X1) relative to the total constituent units constituting the ethylene-unsaturated ester copolymer (A) and the content of ethylene-derived constituent units (X2) relative to the total constituent units constituting the epoxy group-containing ethylene copolymer (B) is 10% by mass or less. [2] The adhesive resin composition according to [1], wherein the melt flow rate of the ethylene-unsaturated ester copolymer (A), measured under conditions of 190°C and a 2160g load in accordance with JIS K 7210:1999, is 1g / 10 min or more and 100g / 10 min or less. [3] The adhesive resin composition according to [1] or [2], wherein the ethylene-unsaturated ester copolymer (A) comprises an ethylene-vinyl acetate copolymer. [4] The adhesive resin composition according to any one of [1] to [3], wherein the epoxy group-containing ethylene copolymer (B) comprises at least one selected from the group consisting of ethylene-(meth)acrylate glycidyl copolymer, ethylene-(meth)acrylate glycidyl vinyl acetate copolymer, and ethylene-(meth)acrylate glycidyl (meth)acrylate ester copolymer. [5] The adhesive resin composition according to any one of [1] to [4], wherein the content of ethylene-derived structural units in the epoxy group-containing ethylene copolymer (B) is 82% by mass or less relative to the total structural units constituting the epoxy group-containing ethylene copolymer (B). [6] The adhesive resin composition according to any one of [1] to [5], wherein the epoxy group-containing ethylene copolymer (B) has a Vicat softening point of 65°C or less as defined in JIS K 7206:1999. [7] The adhesive resin composition according to any one of [1] to [6], wherein the epoxy group-containing ethylene copolymer (B) has a melting point of 90°C or less as measured in accordance with JIS K 7121-1987. [8] An adhesive resin composition according to any one of [1] to [7] above, wherein the haze measured by the method described below is 10% or less. (method) The adhesive resin composition is pressed at 140°C and 9.8 MPa, then cooled at 20°C and 14.7 MPa to produce a 3 mm thick press sheet. The haze of the obtained press sheet is then measured using a haze meter in accordance with JIS K 7136:2000. [9] The adhesive resin composition according to any one of [1] to [8], wherein when the total content of the ethylene-unsaturated ester copolymer (A) and the epoxy group-containing ethylene copolymer (B) is 100% by mass, the content of the ethylene-unsaturated ester copolymer (A) is 40% by mass or more and 99% by mass or less.

[10] The adhesive resin composition according to any one of [1] to [9], wherein the total content of the ethylene-unsaturated ester copolymer (A) and the epoxy group-containing ethylene copolymer (B) is 70% by mass or more and 100% by mass or less when the total amount of the adhesive resin composition is considered to be 100% by mass.

[11] An adhesive resin composition according to any one of [1] to

[10] above, wherein the haze measured by the method described below is 5% or less. (method) A glass with a thickness of 3.2 mm, an ionomer resin layer with a thickness of 1500 μm, a sheet composed of the adhesive resin composition with a thickness of 100 μm, and a glass with a thickness of 3.2 mm are laminated in this order, and bonded at a heating temperature of 140 °C, a pressure during heating of 1 atm, and a heating time of 20 minutes. It is gradually cooled by natural cooling to produce a glass laminate for optical property evaluation. Next, the haze of the obtained glass laminate is measured with a haze meter in accordance with JIS K 7136:2000.

[12] The adhesive resin composition according to any one of the above [1] to

[11] , wherein the adhesive strength to the PET film measured by the following method is 15 N / 15 mm or more both initially, after 500 hours, and after 1000 hours. (Method) A glass with a thickness of 3.9 mm (the non-tin surface is the adhesive surface), a sheet composed of the adhesive resin composition with a thickness of 300 μm, and a PET film with a thickness of 100 μm (untreated by corona) are laminated in this order, and bonded at a heating temperature of 140 °C, a pressure during heating of 1 atm, and a heating time of 60 minutes to produce a glass laminate. Then, the glass laminate is left standing in the atmosphere and gradually cooled by natural cooling. A 15-mm-wide slit is made in the sheet portion of the obtained glass laminate to obtain a test piece, which is installed on a tensile tester. The PET film is peeled off at a tensile speed of 100 mm / min and a peeling angle of 180°, and the average stress is determined as the initial adhesive strength (N / 15 mm). The glass laminate is stored under the conditions of 85 °C and a relative humidity of 90%, and the adhesive strength of the glass laminate after 500 hours of storage and the adhesive strength of the glass laminate after 1000 hours of storage are also determined respectively.

[13] The adhesive resin composition according to any one of the above [1] to

[12] , wherein the adhesive strength to the PET film after 1000 hours of storage measured by the following method is 50 N / 15 mm or more. (Method) A glass with a thickness of 3.9 mm (the non-tin surface is the adhesive surface), a sheet made of the adhesive resin composition with a thickness of 300 μm, and a PET film with a thickness of 100 μm (untreated by corona) are laminated in this order, and bonded at a heating temperature of 140 °C, a pressure during heating of 1 atm, and a heating time of 60 minutes to produce a glass laminate. Then, the glass laminate is left standing in the air and gradually cooled by natural cooling. Next, the glass laminate is stored for 1000 hours under the conditions of 85 °C and a relative humidity of 90%. A slit with a width of 15 mm is made in the sheet portion of the obtained glass laminate to obtain a test piece, which is installed on a tensile testing machine. The PET film is peeled off at a tensile speed of 100 mm / min and a peeling angle of 180°, and the average stress is determined as the adhesive strength (N / 15 mm) of the PET film after storage for 1000 hours.

[14] An insulating glass interlayer comprising an adhesive resin layer containing the adhesive resin composition according to any one of [1] to

[13] .

[15] An ionomer resin layer containing an ionomer (C) of an ethylene-unsaturated carboxylic acid copolymer, and an adhesive resin layer containing the adhesive resin composition according to any one of [1] to

[13] , and a polyester resin layer containing a polyester resin (D), and An insulating glass interlayer comprising them in this order.

[16] The ionomer resin layer and the adhesive resin layer are adjacent, The polyester resin layer is adjacent to the surface of the adhesive resin layer opposite to the surface adjacent to the ionomer resin layer. The insulating glass interlayer according to

[15] .

[17] The insulating glass interlayer according to any one of

[14] to

[16] , and transparent plate-like members provided on both sides of the insulating glass interlayer, and Insulating glass comprising them.

[18] The insulating glass according to

[17] , comprising at least one configuration in which the transparent plate-like member and the ionomer resin layer are adjacent.

[19] A solar cell encapsulant comprising an adhesive resin layer containing the adhesive resin composition described in any of the above [1] to

[13] .

[20] Solar cell element and A sealing resin comprising the solar cell sealing material described in

[19] above for sealing the solar cell element, A solar cell module equipped with the following features. [Effects of the Invention]

[0013] According to the present invention, it is possible to provide an adhesive resin composition with improved transparency and adhesion to a polyester resin layer, as well as a laminated glass interlayer, laminated glass, solar cell encapsulant, and solar cell module with improved transparency, adhesion to a polyester resin layer, and adhesion to glass. [Modes for carrying out the invention]

[0014] The present invention will be described below based on embodiments. In this specification, unless otherwise specified, "A to B" indicating a numerical range means A or greater and B or less. Also, "(meth)acrylic acid" means "at least one selected from the group consisting of acrylic acid and methacrylic acid," and "(meth)acrylate" means "at least one selected from the group consisting of acrylate and methacrylate."

[0015] 1.Adhesive resin composition The adhesive resin composition of the present invention comprises an ethylene-unsaturated ester copolymer (A) (hereinafter also referred to as "polymer (A)") and an epoxy group-containing ethylene copolymer (B) (hereinafter also referred to as "polymer (B)"), wherein the content of constituent units derived from unsaturated ester in the ethylene-unsaturated ester copolymer (A) is greater than 20% by mass relative to the total constituent units constituting the ethylene-unsaturated ester copolymer (A), and the absolute value of the difference (X1-X2) between the content of constituent units derived from ethylene (X1) relative to the total constituent units constituting the ethylene-unsaturated ester copolymer (A) and the content of constituent units derived from ethylene (X2) relative to the total constituent units constituting the epoxy group-containing ethylene copolymer (B) (hereinafter also referred to as "ethylene content difference") is 10% by mass or less. However, the ethylene-unsaturated ester copolymer (A) is excluded from the epoxy group-containing ethylene copolymer (B).

[0016] The adhesive resin composition according to the present invention can improve transparency and adhesion to polyester resin layers. Furthermore, the adhesive resin composition according to the present invention can realize laminated glass interlayers, laminated glass, solar cell encapsulants, and solar cell modules with improved transparency, adhesion to polyester resin layers, and adhesion to glass. The reasons for these effects are presumed to be as follows: First, it is believed that the adhesion to the polyester resin layer can be improved by using a combination of ethylene-unsaturated ester copolymer (A) and epoxy group-containing ethylene copolymer (B). Furthermore, by setting the content of unsaturated ester-derived constituent units in ethylene-unsaturated ester copolymer (A) to above the lower limit, the crystallinity of ethylene-unsaturated ester copolymer (A) is reduced. By setting the difference in ethylene content to below the upper limit, the compatibility between ethylene-unsaturated ester copolymer (A) and epoxy group-containing ethylene copolymer (B) is improved. Additionally, transparency can be improved by reducing the difference in refractive index between the respective copolymers.

[0017] In the adhesive resin composition according to the present invention, the ethylene content difference is 10% by mass or less, but from the viewpoint of further improving transparency and adhesion to the polyester resin layer, it is preferably 8% by mass or less, more preferably 6% by mass or less, even more preferably 4% by mass or less, even more preferably 3% by mass or less, and preferably 0% by mass or more.

[0018] In the adhesive resin composition according to the present invention, when the total content of ethylene-unsaturated ester copolymer (A) and epoxy group-containing ethylene copolymer (B) is taken as 100% by mass, the content of ethylene-unsaturated ester copolymer (A) is preferably 40% by mass or more, more preferably 45% by mass or more, and even more preferably 50% by mass or more, from the viewpoint of further improving transparency, adhesion to the polyester resin layer, and processability, and preferably 99% by mass or less, more preferably 97% by mass or less, and even more preferably 95% by mass or less.

[0019] In the adhesive resin composition according to the present invention, the total content of ethylene-unsaturated ester copolymer (A) and epoxy group-containing ethylene copolymer (B) is preferably 70% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, and preferably 100% by mass or less, when the total adhesive resin composition is considered as 100% by mass, from the viewpoint of further improving transparency and adhesion to the polyester resin layer.

[0020] The following describes each component constituting the adhesive resin composition according to the present invention.

[0021] <Ethylene-unsaturated ester copolymer (A)> Ethylene-unsaturated ester copolymer (A) is a polymer obtained by copolymerizing ethylene with at least one unsaturated ester. Examples of ethylene-unsaturated ester copolymer (A) include copolymers containing ethylene and an unsaturated ester. Furthermore, it is preferable that the ethylene-unsaturated ester copolymer (A) includes at least one polymer selected from the group consisting of ethylene-vinyl ester copolymers and ethylene-unsaturated carboxylic acid ester copolymers. Furthermore, the ethylene-unsaturated ester copolymer (A) may also contain polymerizable monomers other than ethylene and unsaturated esters, such as olefins like propylene, butene, and hexene.

[0022] As the ethylene-vinyl ester copolymer, at least one selected from the group consisting of, for example, ethylene-vinyl acetate copolymer, ethylene-vinyl propionate copolymer, ethylene-vinyl butyrate copolymer, and ethylene-vinyl stearate copolymer can be used.

[0023] Ethylene-unsaturated carboxylic acid copolymers are polymers obtained by copolymerizing ethylene with at least one type of unsaturated carboxylic acid ester. Specifically, a copolymer consisting of ethylene and an unsaturated alkyl carboxylate can be given as an example.

[0024] As the unsaturated carboxylic acid in the unsaturated carboxylic acid ester, at least one selected from the group consisting of acrylic acid, methacrylic acid, 2-ethylacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, maleic anhydride, fumaric anhydride, itaconic anhydride, monomethyl maleate, and monoethyl maleate can be used. Among these, the above unsaturated carboxylic acid is preferably one selected from the group consisting of acrylic acid and methacrylic acid, from the viewpoint of improving the productivity and hygiene of the ethylene-unsaturated ester copolymer (A).

[0025] Examples of alkyl groups in unsaturated carboxylic acid alkyl esters include those with 1 to 12 carbon atoms, and more specifically, alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, secondary butyl, 2-ethylhexyl, and isooctyl can be cited. In this embodiment, the number of carbon atoms in the alkyl group of the alkyl ester is preferably 1 to 8, and more preferably 1 to 4.

[0026] The unsaturated carboxylic acid ester preferably includes at least one selected from the group consisting of (meth)acrylic acid esters such as methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, n-propyl (meth)acrylate, isobutyl (meth)acrylate, n-butyl (meth)acrylate, isooctyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate. These unsaturated carboxylic acid esters may be used individually or in combination of two or more. Among these, it is more preferable to include at least one selected from the group consisting of methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, n-propyl (meth)acrylate, isobutyl (meth)acrylate, and n-butyl (meth)acrylate.

[0027] In this embodiment, the preferred ethylene-unsaturated carboxylic acid copolymer is an ethylene-(meth)acrylic acid copolymer. Among these, copolymers consisting of one compound as the (meth)acrylic acid ester are preferred. Examples of such copolymers include at least one selected from the group consisting of ethylene-(meth)acrylate methyl copolymer, ethylene-(meth)acrylate ethyl copolymer, ethylene-(meth)acrylate isopropyl copolymer, ethylene-(meth)acrylate n-propyl copolymer, ethylene-(meth)acrylate isobutyl copolymer, ethylene-(meth)acrylate n-butyl copolymer, ethylene-(meth)acrylate isooctyl copolymer, and ethylene-(meth)acrylate 2-ethylhexyl copolymer.

[0028] The ethylene-unsaturated ester copolymer (A) preferably contains at least one selected from the group consisting of ethylene-vinyl acetate copolymer, ethylene-(meth)acrylate methyl copolymer, ethylene-(meth)acrylate ethyl copolymer, ethylene-(meth)acrylate isopropyl copolymer, ethylene-(meth)acrylate n-propyl copolymer, ethylene-(meth)acrylate isobutyl copolymer, and ethylene-(meth)acrylate n-butyl copolymer, more preferably contains ethylene-vinyl acetate copolymer, and even more preferably is ethylene-vinyl acetate copolymer. In this embodiment, the ethylene-unsaturated ester copolymer (A) may be used alone or in combination of two or more types.

[0029] The melt flow rate (MFR) of the ethylene-unsaturated ester copolymer (A), measured under conditions of 190°C and a 2160g load in accordance with JIS K 7210:1999, is preferably 1g / 10 min or more, more preferably 10g / 10 min or more, even more preferably 11g / 10 min or more, even more preferably 12g / 10 min or more, and even more preferably 13g / 10 min or more, from the viewpoint of further improving transparency and adhesion to the polyester resin layer. From the viewpoint of further improving the heat resistance, mechanical strength, transparency, etc. of the resulting laminated glass interlayer and solar cell encapsulant, it is preferably 100g / 10 min or less, more preferably 50g / 10 min or less, even more preferably 30g / 10 min or less, even more preferably 20g / 10 min or less, even more preferably 18g / 10 min or less, and even more preferably 15g / 10 min or less. The MFR of ethylene-unsaturated ester copolymer (A) may be prepared by blending multiple ethylene-unsaturated ester copolymers (A) having different MFRs. In this case, when multiple ethylene-unsaturated ester copolymers (A) having different MFRs are blended, the MFR of the blend is considered to be the MFR of ethylene-unsaturated ester copolymer (A).

[0030] The content of ethylene-derived structural units in the ethylene-unsaturated ester copolymer (A) is preferably 50% by mass or more, more preferably 55% by mass or more, even more preferably 60% by mass or more, and even more preferably 65% ​​by mass or more, relative to the total structural units constituting the ethylene-unsaturated ester copolymer (A), from the viewpoint of further improving heat resistance, mechanical strength, water resistance, processability, productivity, etc., and preferably 80% by mass or less, more preferably 76% by mass or less, even more preferably 73% by mass or less, even more preferably 70% by mass or less, and even more preferably 68% by mass or less, from the viewpoint of further improving transparency, flexibility, and adhesion to the polyester resin layer.

[0031] The content of unsaturated ester-derived constituent units in the ethylene-unsaturated ester copolymer (A) is more than 20% by mass relative to the total constituent units of the ethylene-unsaturated ester copolymer (A). However, from the viewpoint of further improving transparency, flexibility, and adhesion to the polyester resin layer, it is preferably 24% by mass or more, more preferably 27% by mass or more, even more preferably 30% by mass or more, and even more preferably 32% by mass or more. From the viewpoint of further improving heat resistance, mechanical strength, water resistance, processability, productivity, etc., it is preferably 50% by mass or less, more preferably 45% by mass or less, even more preferably 40% by mass or less, and even more preferably 35% by mass or less. When the unsaturated ester is vinyl acetate, the content of constituent units derived from the unsaturated ester can be measured, for example, in accordance with JIS K 7192:1999. When the unsaturated ester is an unsaturated carboxylic acid ester, the content of constituent units derived from the unsaturated ester can be measured, for example, by the infrared absorption spectrum (IR) attributed to the unsaturated carboxylic acid ester. For example, when the unsaturated carboxylic acid ester is ethyl acrylate (EA), the 860 cm⁻¹ spectrum attributed to EA can be measured. -1 It is determined from the absorbance. However, the calibration curve is obtained by determining the EA concentration by nuclear magnetic resonance spectroscopy (NMR) and the IR at 860 cm⁻¹. -1 It is determined by its correlation with the absorbance.

[0032] The method for producing the ethylene-unsaturated ester copolymer (A) is not particularly limited and can be produced by known methods. For example, it can be obtained by radical copolymerization of each polymerization component under high temperature and high pressure. Alternatively, commercially available ethylene-unsaturated ester copolymer (A) may be used.

[0033] From the viewpoint of further improving adhesion, it is preferable that at least a portion of the ethylene-unsaturated ester copolymer (A) is modified with a silane coupling agent. Here, it is preferable that the silane coupling agent in the ethylene-unsaturated ester copolymer (A) includes at least one selected from the group consisting of a silane coupling agent having a polymerizable group, a silane coupling agent having an amino group, and a silane coupling agent having an epoxy group. From the viewpoint of further improving adhesion, the content of the silane coupling agent is preferably 0.02 parts by mass or more, more preferably 0.1 parts by mass or more, even more preferably 0.5 parts by mass or more, preferably 5 parts by mass or less, more preferably 4 parts by mass or less, and even more preferably 3 parts by mass or less, per 100 parts by mass of ethylene-unsaturated ester copolymer (A).

[0034] Here, the modification of the silane coupling agent to the ethylene-unsaturated ester copolymer (A) can be carried out by a method similar to that used for modifying the silane coupling agent to the epoxy group-containing ethylene copolymer (B), which will be described later. Furthermore, the modification of the silane coupling agent to the ethylene-unsaturated ester copolymer (A) and the modification of the silane coupling agent to the epoxy group-containing ethylene copolymer (B) may be carried out simultaneously. When modifying an ethylene-unsaturated ester copolymer (A) with a silane coupling agent and modifying an epoxy group-containing ethylene copolymer (B) with a silane coupling agent simultaneously, the content of the polymerization initiator used for modification is preferably 0.05 parts by mass or more, more preferably 0.1 parts by mass or more, even more preferably 0.2 parts by mass or more, preferably 5 parts by mass or less, more preferably 3 parts by mass or less, even more preferably 1.5 parts by mass or less, even more preferably 1 part by mass or less, and even more preferably 0.3 parts by mass or less, based on 100 parts by mass of the total of the ethylene-unsaturated ester copolymer (A) and the epoxy group-containing ethylene copolymer (B). From the viewpoint of further improving adhesion, the content of the silane coupling agent is preferably 0.02 parts by mass or more, more preferably 0.1 parts by mass or more, even more preferably 0.5 parts by mass or more, preferably 5 parts by mass or less, more preferably 4 parts by mass or less, even more preferably 3 parts by mass or less, and even more preferably 1.5 parts by mass or less, based on 100 parts by mass of the total of the ethylene-unsaturated ester copolymer (A) and the epoxy group-containing ethylene copolymer (B).

[0035] <Epoxy group-containing ethylene copolymer (B)> Examples of epoxy group-containing ethylene copolymers (B) include glycidyl group-containing ethylene copolymers. As the glycidyl group-containing ethylene copolymer, from the viewpoint of further improving transparency and adhesion to the polyester resin layer, it is preferably at least one selected from the group consisting of ethylene-(meth)acrylate glycidyl copolymer, ethylene-(meth)acrylate glycidyl vinyl acetate copolymer, and ethylene-(meth)acrylate glycidyl (meth)acrylate ester copolymer, more preferably ethylene-(meth)acrylate glycidyl (meth)acrylate ester copolymer, even more preferably ethylene-(meth)acrylate glycidyl (meth)acrylate methyl copolymer, and even more preferably ethylene-methacrylate glycidyl methyl acrylate copolymer.

[0036] The epoxy group-containing ethylene copolymer (B) can be obtained by copolymerizing a monomer having a polymerizable group and an epoxy group, such as glycidyl (meth)acrylate (hereinafter also referred to as "glycidyl (meth)acrylate"), vinyl glycidyl ether, 1,2-epoxy-4-vinylcyclohexane, or 3,4-epoxycyclohexylmethyl methacrylate, with ethylene. Alternatively, epoxy groups may be introduced into the ethylene copolymer by graft polymerization of a monomer having an epoxy group.

[0037] The content of constituent units derived from monomers having epoxy groups in the epoxy group-containing ethylene copolymer (B) is preferably 0.5% by mass or more, more preferably 1% by mass or more, even more preferably 2% by mass or more, and even more preferably 3% by mass or more, relative to the total constituent units of the epoxy group-containing ethylene copolymer (B), from the viewpoint of further improving adhesion, transparency and flexibility, and preferably 30% by mass or less, more preferably 20% by mass or less, even more preferably 10% by mass or less, even more preferably 8% by mass or less, and even more preferably 6% by mass or less, from the viewpoint of further improving processability. Furthermore, "(meth)acrylate glycidyl" refers to at least one selected from the group consisting of methacrylate glycidyl and acrylate glycidyl.

[0038] In epoxy group-containing ethylene copolymer (B), "ethylene copolymer" means that the main component is a constituent unit derived from ethylene. Furthermore, "main component" here means that the content of "ethylene-derived constituent units" is the largest among all constituent units. For example, in the case of a copolymer consisting of constituent units derived from ethylene, glycidyl (meth)acrylate, and vinyl acetate, the proportion of ethylene-derived constituent units is greater than that of constituent units derived from glycidyl (meth)acrylate or vinyl acetate. The content of ethylene-derived structural units in the epoxy group-containing ethylene copolymer (B) is preferably 50% by mass or more, more preferably 55% by mass or more, even more preferably 60% by mass or more, even more preferably 65% ​​by mass or more, and even more preferably 67% by mass or more, relative to the total structural units constituting the epoxy group-containing ethylene copolymer (B), from the viewpoint of improving productivity, and preferably 82% by mass or less, more preferably 80% by mass or less, even more preferably 78% by mass or less, even more preferably 75% by mass or less, even more preferably 72% by mass or less, and even more preferably 70% by mass or less, from the viewpoint of further improving transparency and adhesion to the polyester resin layer.

[0039] The epoxy group-containing ethylene copolymer (B) may further contain other monomer units other than ethylene and monomers having epoxy groups. Other monomers include vinyl esters such as vinyl acetate and vinyl propionate; and unsaturated carboxylic acid esters such as acrylic acid esters, methacrylic acid esters, ethacrylic acid esters, crotonic acid esters, fumarate esters, maleic acid esters, maleic anhydride esters, itaconic acid esters, and itaconic anhydride esters. Ester groups can include alkyl ester groups having 1 to 12 carbon atoms, and more specifically, alkyl ester groups such as methyl esters, ethyl esters, n-propyl esters, isopropyl esters, n-butyl esters, isobutyl esters, secondary butyl esters, 2-ethylhexyl esters, and isooctyl esters. Among these, at least one selected from the group consisting of vinyl acetate and (meth)acrylic acid esters is preferred.

[0040] Specifically, examples include copolymers containing a constituent unit derived from ethylene and a constituent unit derived from glycidyl (meth)acrylate, as well as copolymers containing, in addition to these two constituent units, at least one constituent unit selected from the group consisting of a constituent unit derived from vinyl acetate and a constituent unit derived from (meth)acrylic acid ester.

[0041] The content of constituent units derived from monomers other than ethylene and monomers having epoxy groups in the epoxy group-containing ethylene copolymer (B) is preferably 1% by mass or more, more preferably 5% by mass or more, even more preferably 10% by mass or more, even more preferably 15% by mass or more, even more preferably 20% by mass or more, even more preferably 25% by mass or more, even more preferably 26% by mass or more, and preferably 40% by mass or less, more preferably 35% by mass or less, even more preferably 30% by mass or less, even more preferably 29% by mass or less, and even more preferably 28% by mass or less, relative to all constituent units of the epoxy group-containing ethylene copolymer (B), from the viewpoint of further improving transparency and adhesion to glass and polyester resin layers.

[0042] The epoxy group-containing ethylene copolymer (B) may be used alone or in combination of two or more types.

[0043] From the viewpoint of further improving adhesion to glass or polyester resin layers, it is preferable that at least a portion of the epoxy group-containing ethylene copolymer (B) is modified with a silane coupling agent.

[0044] In the adhesive resin composition according to the present invention, it is preferable that the silane coupling agent in the epoxy group-containing ethylene copolymer (B) contains at least one selected from the group consisting of a silane coupling agent having polymerizable groups, a silane coupling agent having amino groups, and a silane coupling agent having epoxy groups. Here, the modification of the silane coupling agent to the epoxy group-containing ethylene copolymer (B) can be performed, for example, by reacting the epoxy group-containing ethylene copolymer (B) with a silane coupling agent having an amino group or an epoxy group under heating (for example, at 100°C to 200°C) (modification method 1), or by graft polymerization of a polymerizable silane coupling agent onto the epoxy group-containing ethylene copolymer (B) using a polymerization initiator (modification method 2). In modification method 1, the silane coupling agent is introduced into the side chains of the epoxy group-containing ethylene copolymer (B) by a reaction between the amino group or epoxy group in the silane coupling agent and the glycidyl group in the epoxy group-containing ethylene copolymer (B). In modification method 2, for example, an epoxy group-containing ethylene copolymer (B), a silane coupling agent having polymerizable groups, and a radical polymerization initiator can be produced by melt-kneading them together using an extruder, kneader, Banbury mixer, etc., at a temperature above the melting point of the epoxy group-containing ethylene copolymer (B) and above the decomposition temperature of the radical polymerization initiator. These reactions can also be carried out in solution.

[0045] While commonly used polymerization initiators can be used, organic peroxides are preferred. As organic peroxides, known organic peroxides that can be used as polymerization initiators can be used, specifically including diacyl peroxide compounds, alkyl peroxyester compounds, peroxydicarbonate compounds, peroxycarbonate compounds, peroxyketal compounds, dialkyl peroxide compounds, hydroperoxide compounds, ketone peroxide compounds, and the like. Among these, dialkylperoxide compounds are preferred, with 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, 1,3-di(2-t-butylperoxyisopropyl)benzene, di-t-butylperoxide, and 2,5-dimethyl-2,5-di(t-butylperoxy)hexyn-3 being more preferred.

[0046] Examples of silane coupling agents having polymerizable groups include vinyltrimethoxysilane, vinyltriethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropylmethyldimethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-acryloxypropylmethyldiethoxysilane, and 3-acryloxypropyltriethoxysilane. Examples of silane coupling agents containing an amino group include N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethylbutylidene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, and hydrochloride salts of N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane. Examples of silane coupling agents having an epoxy group include 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, and 3-glycidoxypropyltriethoxysilane.

[0047] From the viewpoint of further improving adhesion to glass and polyester resin layers, the content of the polymerization initiator used for modification is preferably 0.1 parts by mass or more, more preferably 0.3 parts by mass or more, and preferably 5 parts by mass or less, more preferably 3 parts by mass or less, even more preferably 1.0 part by mass or less, and even more preferably 0.6 parts by mass or less, per 100 parts by mass of epoxy group-containing ethylene copolymer (B). From the viewpoint of further improving adhesion to glass and polyester resin layers, the content of the silane coupling agent is preferably 0.02 parts by mass or more, preferably 5 parts by mass or less, more preferably 4 parts by mass or less, and even more preferably 3 parts by mass or less, per 100 parts by mass of epoxy group-containing ethylene copolymer (B).

[0048] The Vicat softening point of the epoxy group-containing ethylene copolymer (B), as defined in JIS K 7206:1999, is preferably 65°C or lower, more preferably 50°C or lower, even more preferably 40°C or lower, even more preferably 30°C or lower, and even more preferably 25°C or lower, from the viewpoint of further improving adhesion to glass and polyester resin layers, and is preferably 20°C or higher from the viewpoint of heat resistance and processability.

[0049] The melting point of epoxy group-containing ethylene copolymer (B), as measured in accordance with JIS K 7121-1987, is preferably 90°C or lower, more preferably 80°C or lower, even more preferably 70°C or lower, even more preferably 65°C or lower, and even more preferably 60°C or lower, from the viewpoint of further improving adhesion to glass and polyester resin layers, and preferably 30°C or higher, more preferably 40°C or higher, even more preferably 45°C or higher, and even more preferably 52°C or higher, from the viewpoint of heat resistance and processability.

[0050] The melt flow rate (MFR) of epoxy group-containing ethylene copolymer (B), measured in accordance with JIS K 7210:1999 under conditions of 190°C and a 2160g load, is preferably 0.1g / 10min or more, more preferably 1g / 10min or more, even more preferably 2g / 10min or more, even more preferably 3g / 10min or more, even more preferably 4g / 10min or more, and preferably 100g / 10min or less, more preferably 50g / 10min or less, even more preferably 20g / 10min or less, and even more preferably 10g / 10min or less.

[0051] <Other ingredients> The adhesive resin composition according to the present invention may contain components other than ethylene-unsaturated ester copolymer (A) and epoxy group-containing ethylene copolymer (B), as long as the objectives of the present invention are not impaired. Other components are not particularly limited, but examples include plasticizers, antioxidants, ultraviolet absorbers, wavelength converters, antistatic agents, surfactants, colorants, light stabilizers, foaming agents, lubricants, crystal nucleating agents, crystallization accelerators, crystallization retarders, catalyst deactivators, heat absorbers, heat reflectors, heat dissipators, thermoplastic resins, thermosetting resins, inorganic fillers, organic fillers, impact resistance modifiers, slip agents, crosslinking agents, crosslinking aids, silane coupling agents, tackifiers, processing aids, mold release agents, hydrolysis inhibitors, heat stabilizers, antiblocking agents, antifogging agents, flame retardants, flame retardant aids, light diffusing agents, antibacterial agents, antifungal agents, dispersants, and other resins. These other components may be used individually or in combination of two or more.

[0052] From the viewpoint of further improving transparency, the adhesive resin composition according to the present invention has a haze of preferably 10% or less, more preferably 9% or less, and even more preferably 8.4% or less, as measured by the following method. (method) The adhesive resin composition is pressed at 140°C and 9.8 MPa, then cooled at 20°C and 14.7 MPa to produce a 3 mm thick press sheet. The haze of the obtained press sheet is then measured using a haze meter in accordance with JIS K 7136:2000.

[0053] From the viewpoint of further improving the transparency of the resulting laminated glass or solar cell module, the adhesive resin composition according to the present invention preferably has a haze of 5% or less, more preferably 4% or less, and even more preferably 3.0% or less, as measured by the following method. (method) A 3.2 mm thick glass, a 1500 μm thick ionomer resin layer, and a 100 μm thick sheet of the adhesive resin composition are laminated in this order, and the layers are bonded together at a heating temperature of 140°C, a heating pressure of 1 atm, and a heating time of 20 minutes. The laminate is then slowly cooled by natural cooling to produce a glass laminate for optical property evaluation. Next, the haze of the obtained glass laminate is measured using a haze meter in accordance with JIS K 7136:2000.

[0054] From the viewpoint of further improving adhesion to the polyester resin layer, the adhesive resin composition according to the present invention has an adhesive strength to a PET film measured by the following method, which is preferably 15 N / 15 mm or more, more preferably 18 N / 15 mm or more, and even more preferably 20 N / 15 mm or more, at the initial stage, after 500 hours, and after 1000 hours. (method) A glass laminate is prepared by laminating a 3.9 mm thick glass (non-tin side as the bonding surface), a 300 μm thick sheet of the adhesive resin composition, and a 100 μm thick PET film (untreated with corona) in this order, and bonding them together at a heating temperature of 140°C, a heating pressure of 1 atm, and a heating time of 60 minutes. The glass laminate is then left to stand in the air and cooled slowly by natural cooling. A 15 mm wide slit is made in the sheet portion of the obtained glass laminate to create a test specimen, which is then placed on a tensile testing machine. The PET film is peeled off at a tensile speed of 100 mm / min and a peeling angle of 180°, and the mean stress is determined as the initial adhesive strength (N / 15 mm). Here, the mean stress refers to the average value of the stress measured while peeling off the PET film. The glass laminate is stored at 85°C and 90% relative humidity, and the adhesive strength of the glass laminate after 500 hours of storage and after 1000 hours of storage are also determined.

[0055] From the viewpoint of further improving adhesion to the polyester resin layer, the adhesive resin composition according to the present invention has an adhesive strength to a PET film after 1000 hours of storage, measured by the following method, preferably 50 N / 15 mm or more, more preferably 70 N / 15 mm or more, even more preferably 85 N / 15 mm or more, and even more preferably 89.6 N / 15 mm or more. (method) A glass laminate is prepared by laminating a 3.9 mm thick glass (non-tin side as the bonding surface), a 300 μm thick sheet of the adhesive resin composition, and a 100 μm thick PET film (untreated with corona) in this order, and bonding them together at a heating temperature of 140°C, a heating pressure of 1 atm, and a heating time of 60 minutes. The glass laminate is then left to stand in the air and allowed to cool slowly by natural cooling. Next, the glass laminate is stored for 1000 hours at 85°C and 90% relative humidity. A 15 mm wide slit is made in the sheet portion of the obtained glass laminate to create a test specimen, which is then placed on a tensile testing machine. The PET film is peeled off at a tensile speed of 100 mm / min and a peeling angle of 180°, and the average stress is determined as the adhesive strength (N / 15 mm) to the PET film after 1000 hours of storage.

[0056] 2. Laminated glass interlayer The laminated glass interlayer according to the present invention includes an adhesive resin layer containing the adhesive resin composition according to the present invention. The laminated glass interlayer according to the present invention may have a single-layer structure or a multilayer structure of two or more layers. More specifically, the laminated glass interlayer according to the present invention may be a single-layer film consisting of one adhesive resin layer, a multilayer film consisting of two or more adhesive resin layers, or a multilayer film having at least one adhesive resin layer and at least one other layer other than the adhesive resin layer.

[0057] From the viewpoint of further improving adhesive strength and design, the thickness of the adhesive resin layer is preferably 5 μm or more, more preferably 10 μm or more, even more preferably 20 μm or more, even more preferably 30 μm or more, even more preferably 50 μm or more, and even more preferably 75 μm or more. From the viewpoint of further improving the transparency and heat resistance of the resulting laminated glass or solar cell module, the thickness is preferably 2000 μm or less, more preferably 1500 μm or less, even more preferably 1000 μm or less, even more preferably 500 μm or less, and even more preferably 400 μm or less.

[0058] From the viewpoint of further improving transparency and adhesion to glass, the laminated glass interlayer according to the present invention preferably has a multilayer structure comprising an ionomer resin layer containing an ionomer (C) of an ethylene-unsaturated carboxylic acid copolymer and an adhesive resin layer containing the adhesive resin composition according to the present invention. In the case where the laminated glass interlayer according to the present invention has a multilayer structure comprising an ionomer resin layer and an adhesive resin layer, it may be a two-layer structure including an ionomer resin layer and an adhesive resin layer, or it may be a three-layer structure including an ionomer resin layer and two adhesive resin layers formed on both sides of the ionomer resin layer so as to sandwich it. When the laminated glass interlayer according to the present invention has a multilayer structure comprising an ionomer resin layer and an adhesive resin layer, the ratio of the thickness of the ionomer resin layer (thickness a) to the adhesive resin layer (thickness b) (a / b) is preferably 3 / 1 to 80 / 1, more preferably 7 / 1 to 30 / 1, from the viewpoint of further improving adhesion to glass and transparency.

[0059] From the viewpoint of further improving adhesion to glass, transparency, interlayer adhesion, and design properties, the laminated glass interlayer according to the present invention is more preferably a multilayer structure comprising, in this order: an ionomer resin layer containing an ionomer (C) of an ethylene-unsaturated carboxylic acid copolymer; an adhesive resin layer containing the adhesive resin composition according to the present invention; and a polyester resin layer containing a polyester resin (D). When the laminated glass interlayer according to the present invention has a multilayer structure comprising an ionomer resin layer, an adhesive resin layer according to the present invention, and a polyester resin layer in this order, it is preferable that, from the viewpoint of further improving the interlayer adhesion of the laminated glass interlayer according to the present invention, the ionomer resin layer and the adhesive resin layer according to the present invention are adjacent to each other, and the polyester resin layer is adjacent to the side of the adhesive resin layer according to the present invention that is opposite to the side adjacent to the ionomer resin layer.

[0060] When the laminated glass interlayer according to the present invention has a multilayer structure comprising an ionomer resin layer, an adhesive resin layer, and a polyester resin layer, the ratio of the thickness of the ionomer resin layer (thickness a) to the adhesive resin layer (thickness b) (a / b) is preferably 3 / 1 to 80 / 1, and more preferably 7 / 1 to 30 / 1, from the viewpoint of further improving adhesion and transparency.

[0061] <Ionomer resin layer> The ionomer resin layer contains an ionomer (C) of an ethylene-unsaturated carboxylic acid copolymer (hereinafter also referred to as "ionomer (C)"), and preferably contains ionomer (C) as the main component. Here, "main component" means that ionomer (C) is contained in the ionomer resin layer at a concentration of 50% by mass or more. The ionomer (C) content in the ionomer resin layer is preferably 60% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, and even more preferably 95% by mass or more, when the total ionomer resin layer is considered as 100% by mass, from the viewpoint of further improving adhesion to glass. There is no particular upper limit to the ionomer (C) content in the ionomer resin layer, but for example, it is 100% by mass or less.

[0062] From the viewpoint of improving mechanical strength, the thickness of the ionomer resin layer is preferably 10 μm or more, more preferably 50 μm or more, even more preferably 100 μm or more, even more preferably 250 μm or more, even more preferably 500 μm or more, even more preferably 750 μm or more, and even more preferably 1000 μm or more. From the viewpoint of improving the transparency of the resulting laminated glass or solar cell module, the thickness is preferably 5000 μm or less, more preferably 3000 μm or less, and even more preferably 2000 μm or less.

[0063] The ionomer (C) of the ethylene-unsaturated carboxylic acid copolymer is an ionomer of a polymer obtained by copolymerizing ethylene with at least one unsaturated carboxylic acid, and is a resin obtained by neutralizing at least a portion of the carboxyl groups of the ethylene-unsaturated carboxylic acid copolymer with metal ions. The ethylene-unsaturated carboxylic acid copolymer, which is the base resin of the ionomer (C) of the ethylene-unsaturated carboxylic acid copolymer, is a polymer obtained by copolymerizing at least ethylene and an unsaturated carboxylic acid as copolymer components, and monomers other than ethylene and unsaturated carboxylic acids may be copolymerized as needed. Ethylene-unsaturated carboxylic acid copolymers may be used alone, or two or more ethylene-unsaturated carboxylic acid copolymers may be used in combination.

[0064] The ethylene-unsaturated carboxylic acid copolymer may take the form of a block copolymer, a random copolymer, or a graft copolymer. However, considering productivity, it is preferable to use a binary random copolymer, a ternary random copolymer, a graft copolymer of a binary random copolymer, or a graft copolymer of a ternary random copolymer, and more preferably a binary random copolymer or a ternary random copolymer.

[0065] Examples of unsaturated carboxylic acids that constitute ethylene-unsaturated carboxylic acid copolymers include acrylic acid, methacrylic acid, ethacrylic acid, itaconic acid, itaconic anhydride, fumaric acid, crotonic acid, maleic acid, maleic anhydride, maleic acid monoesters (such as monomethyl maleic acid and monoethyl maleic acid), and maleic anhydride monoesters (such as monomethyl maleic anhydride and monoethyl maleic acid), which have 4 to 8 carbon atoms. Among these, the unsaturated carboxylic acid is preferably selected from acrylic acid and methacrylic acid, from the viewpoint of improving the productivity of ethylene-unsaturated carboxylic acid copolymers. These unsaturated carboxylic acids may be used individually or in combination of two or more.

[0066] The content of constituent units derived from ethylene in the ethylene-unsaturated carboxylic acid copolymer is preferably 65% ​​by mass or more, more preferably 70% by mass or more, even more preferably 75% by mass or more, and preferably 95% by mass or less, more preferably 90% by mass or less, and even more preferably 85% by mass or less, when the total constituent units of the ethylene-unsaturated carboxylic acid copolymer are taken as 100% by mass, from the viewpoint of further improving heat resistance and processability. The content of constituent units derived from unsaturated carboxylic acids in the ethylene-unsaturated carboxylic acid copolymer is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 15% by mass or more, even more preferably 18% by mass or more, even more preferably 19% by mass or more, and preferably 35% by mass or less, more preferably 30% by mass or less, even more preferably 25% by mass or less, even more preferably 22% by mass or less, and even more preferably 21% by mass or less, when the total constituent units of the ethylene-unsaturated carboxylic acid copolymer are taken as 100% by mass, from the viewpoint of further improving transparency and adhesion. Here, the content of unsaturated carboxylic acid in the ethylene-unsaturated carboxylic acid copolymer can be measured, for example, by Fourier transform infrared absorption spectroscopy (FT-IR).

[0067] The ethylene-unsaturated carboxylic acid copolymer is a copolymer formed by copolymerizing at least ethylene and an unsaturated carboxylic acid, and may also be a three- or more-component polypolymer formed by copolymerizing a third copolymer component. Examples of the third copolymerization component include unsaturated carboxylic acid esters (e.g., alkyl esters of (meth)acrylates such as methyl acrylate, ethyl acrylate, isobutyl acrylate, n-butyl acrylate, isooctyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, isobutyl methacrylate, n-butyl methacrylate, isooctyl methacrylate, 2-ethylhexyl methacrylate, dimethyl maleate, diethyl maleate, etc.), vinyl esters (e.g., vinyl acetate, vinyl propionate, etc.), unsaturated hydrocarbons (e.g., propylene, butene, 1,3-butadiene, pentene, 1,3-pentadiene, 1-hexene, etc.), oxides such as vinyl sulfuric acid and vinyl nitric acid, halogen compounds (e.g., vinyl chloride, vinyl fluoride, etc.), vinyl group-containing primary and secondary amine compounds, carbon monoxide, sulfur dioxide, etc.). Among these, unsaturated carboxylic acid esters are preferred as the third copolymerizing component, and alkyl (meth)acrylate esters (preferably with 1 to 4 carbon atoms in the alkyl group) are more preferred.

[0068] From the viewpoint of production and mixing, the content ratio of the constituent units derived from the third copolymer component in the ethylene-(meth)acrylic acid copolymer is preferably in the range of 25% by mass or less.

[0069] Examples of metal ions constituting the ionomer (C) of the ethylene-unsaturated carboxylic acid copolymer include alkali metal ions such as lithium ions, potassium ions, and sodium ions; and polyvalent metal ions such as calcium ions, magnesium ions, zinc ions, aluminum ions, and barium ions. These metal ions may be used individually or in combination of two or more. Among these, it is preferable to include at least one selected from sodium ions, zinc ions, and magnesium ions, and more preferably to include magnesium ions.

[0070] From the viewpoint of further improving transparency, the degree of neutralization of the ionomer (C) of the ethylene-unsaturated carboxylic acid copolymer is preferably 5 mol% or more, more preferably 10 mol% or more, even more preferably 20 mol% or more, even more preferably 30 mol% or more, and even more preferably 40 mol% or more. From the viewpoint of further improving adhesion, processability and moldability, it is preferably 95 mol% or less, more preferably 90 mol% or less, even more preferably 80 mol% or less, even more preferably 70 mol% or less, even more preferably 60 mol% or less, even more preferably 50 mol% or less, and even more preferably 45 mol% or less. Here, the degree of neutralization of the ionomer (C) of the ethylene-unsaturated carboxylic acid copolymer can be measured, for example, by incineration residue analysis.

[0071] The method for producing the ionomer (C) of the ethylene-unsaturated carboxylic acid copolymer is not particularly limited and can be produced by known methods. Furthermore, commercially available ionomers (C) of the ethylene-unsaturated carboxylic acid copolymer may also be used.

[0072] The melt flow rate (MFR) of the ionomer (C) of the ethylene-unsaturated carboxylic acid copolymer, measured under conditions of 190°C and a 2160g load in accordance with JIS K 7210:1999, is preferably 0.1g / 10min or more, more preferably 0.5g / 10min or more, even more preferably 1.0g / 10min or more, even more preferably 1.5g / 10min or more, even more preferably 2.0g / 10min or more, and preferably 30g / 10min or less, more preferably 15g / 10min or less, even more preferably 10g / 10min or less, even more preferably 5g / 10min or less, and even more preferably 3.0g / 10min or less.

[0073] The ionomer resin layer may contain components other than the ionomer (C) of the ethylene-unsaturated carboxylic acid copolymer, as long as it does not impair the objectives of the present invention. The other components are not particularly limited, but examples include plasticizers, antioxidants, UV absorbers, antistatic agents, surfactants, colorants, light stabilizers, foaming agents, lubricants, crystal nucleating agents, crystallization accelerators, crystallization retarders, catalyst deactivators, thermoplastic resins other than ionomer (C), thermosetting resins, inorganic fillers, organic fillers, impact resistance modifiers, slip agents, crosslinking agents, crosslinking aids, tackifiers, silane coupling agents, processing aids, mold release agents, hydrolysis inhibitors, heat stabilizers, antiblocking agents, antifogging agents, flame retardants, flame retardant aids, light diffusing agents, antibacterial agents, antifungal agents, dispersants, and other resins. The other components may be used individually or in combination of two or more. However, it is preferable that the ionomer resin layer does not contain epoxy group-containing ethylene copolymers.

[0074] <Polyester resin layer> The polyester resin layer contains polyester resin (D), preferably with polyester resin (D) as the main component. Here, "main component" means that polyester resin (D) is contained in the polyester resin layer at a concentration of 50% by mass or more. The polyester resin (D) content in the polyester resin layer is preferably 60% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, and even more preferably 95% by mass or more, when the total polyester resin layer is considered to be 100% by mass. There is no particular upper limit to the polyester resin (D) in the polyester resin layer, but for example, it is 100% by mass or less.

[0075] The thickness of the polyester resin layer is preferably 5 μm or more, more preferably 10 μm or more, even more preferably 20 μm or more, even more preferably 30 μm or more, even more preferably 50 μm or more, and even more preferably 75 μm or more, from the viewpoint of further improving mechanical strength and design, and preferably 2000 μm or less, more preferably 1000 μm or less, even more preferably 500 μm or less, even more preferably 200 μm or less, and even more preferably 150 μm or less, from the viewpoint of further improving the transparency and interlayer adhesion of the resulting laminated glass or solar cell module.

[0076] Examples of polyester resin (D) include polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT), and polyethylene naphthalate (PEN). The surface of the polyester resin layer may be treated with an easy-adhesion treatment such as a coating. The polyester resin layer may also be a multilayer film composed of the above-mentioned multiple types of polyester resin layers.

[0077] The polyester resin layer can be industrially manufactured as a single-layer film made of the above-mentioned polyester by the known T-die-casting film method, or as a co-extruded film using two or more types of polyester or other resins besides polyester by the co-extrusion T-die-casting film method. These may be unstretched, but stretched films are preferred from the viewpoint of further improving the toughness, transparency, heat resistance, gas barrier properties, etc. of the film.

[0078] The overall thickness of the laminated glass interlayer according to the present invention is preferably 0.1 mm or more, more preferably 0.2 mm or more, and even more preferably 0.3 mm or more, from the viewpoint of further improving mechanical strength, and preferably 10 mm or less, more preferably 5 mm or less, and even more preferably 3 mm or less, from the viewpoint of further improving the transparency and interlayer adhesion of the resulting laminated glass.

[0079] The method for manufacturing the laminated glass interlayer according to the present invention is not particularly limited, and conventionally known manufacturing methods can be used. As a method for manufacturing the laminated glass interlayer according to the present invention, for example, press molding, extrusion molding, T-die molding, injection molding, compression molding, casting, calendering, inflation molding, and the like can be used.

[0080] 3. Laminated glass The laminated glass according to the present invention comprises a laminated glass interlayer according to the present invention and transparent plate-like members provided on both sides of the laminated glass interlayer. Herein, in this specification, the "transparent plate-like member" is also referred to as "glass". The laminated glass according to the present invention has improved transparency and interlayer adhesion due to the inclusion of the laminated glass interlayer according to the present invention. The laminated glass interlayer may consist of two or more layers, or it may consist of three or more layers by sandwiching a layer made of another resin between two laminated glass interlayers.

[0081] Examples of the layer configurations of the laminated glass according to the present invention include the configurations shown in the following examples 1 to 3. Example 1: Transparent plate-like member / Ionomer resin layer / Adhesive resin layer / Transparent plate-like member Example 2: Transparent plate-like member / Ionomer resin layer / Adhesive resin layer / Polyester resin layer / Adhesive resin layer / Transparent plate-like member Example 3: Transparent plate-like member / Ionomer resin layer / Adhesive resin layer / Polyester resin layer / Adhesive resin layer / Ionomer resin layer / Transparent plate-like member The laminated glass according to the present invention preferably includes at least one configuration in which a transparent plate-like member and an ionomer resin layer are adjacent to each other. By providing an ionomer resin layer between the transparent plate-like member and the adhesive resin layer, the durability of the laminated glass can be further improved.

[0082] The transparent plate-like member is not particularly limited, but for example, commonly used transparent plate glass can be used, such as inorganic glass like float glass, polished plate glass, patterned glass, wired plate glass, reinforced plate glass, colored plate glass, heat-absorbing plate glass, heat-reflective plate glass, and green glass. Organic plastic plates such as polycarbonate plates, poly(meth)acrylate plates, polymethyl(meth)acrylate plates, polystyrene plates, cyclic polyolefin plates, polyethylene terephthalate plates, polyethylene naphthalate plates, and polyethylene butyrate plates can also be used. Among these, transparent plate glass is preferred, and inorganic glass is more preferred. Furthermore, the transparent plate-like member may be subjected to surface treatments such as corona treatment, plasma treatment, or flame treatment as appropriate.

[0083] The thickness of the transparent plate-like member is preferably 0.1 mm or more, more preferably 0.5 mm or more, even more preferably 1 mm or more, preferably 20 mm or less, more preferably 10 mm or less, and even more preferably 5 mm or less. In the laminated glass according to the present invention, the transparent plate-like members provided on both sides of the laminated glass interlayer may be the same, or different plate-like members may be used in combination.

[0084] The method for manufacturing laminated glass according to the present invention is not particularly limited, and conventionally known manufacturing methods such as the nip roll method, autoclave method, vacuum bag method, and vacuum laminator method can be used. One of these methods may be used for manufacturing, or two or more manufacturing methods may be combined for manufacturing. As a method for manufacturing laminated glass according to the present invention, for example, a method is used in which the laminated glass interlayer according to the present invention is sandwiched between two transparent plate-shaped members, and then heated and pressurized. Among these, the method for manufacturing laminated glass according to the present invention is preferably a method that combines the nip roll method and the autoclave method, or a method that combines the vacuum bag method and the autoclave method. A method combining the nip roll method and the autoclave method involves, for example, sandwiching the laminated glass interlayer according to the present invention between two transparent plate-shaped members, pre-pressing the resulting laminate with a nip roll, and then heat-pressing the laminate using an autoclave to obtain laminated glass. A method combining the vacuum bag method and the autoclave method involves, for example, sandwiching the laminated glass interlayer according to the present invention between two transparent plate-shaped members to obtain a laminate, placing the resulting laminate in a vacuum bag, then reducing the pressure inside the vacuum bag to temporarily bond the laminate, and finally using an autoclave to heat-pressure the laminate to heat-bond it and obtain laminated glass.

[0085] The laminated glass according to the present invention can be used for a variety of purposes, such as architectural laminated glass, automotive laminated glass, general buildings, agricultural buildings, railway windows, etc., but is not limited to these uses.

[0086] 4. Solar cell encapsulant The solar cell encapsulant according to the present invention includes an adhesive resin layer containing the adhesive resin composition according to the present invention. The layer structure of the solar cell encapsulant according to the present invention and preferred embodiments of each layer are the same as those of the laminated glass interlayer according to the present invention, so a detailed explanation is omitted here. Furthermore, the solar cell encapsulant according to the present invention can be manufactured using the same manufacturing method as the laminated glass interlayer according to the present invention.

[0087] 5. Solar cell modules The solar cell module according to the present invention comprises a solar cell element and a sealing resin layer composed of the solar cell sealing material according to the present invention for sealing the solar cell element. The solar cell module according to the present invention has improved transparency and interlayer adhesion due to the inclusion of a sealing resin layer composed of the solar cell sealing material according to the present invention. The solar cell module according to the present invention may further include a substrate into which sunlight is incident, protective materials, etc., as needed. The substrate into which sunlight is incident may also be simply referred to as the substrate. The solar cell module according to the present invention can be manufactured, for example, by sandwiching solar cell elements with a solar cell encapsulant, and then sandwiching these between a substrate and a protective material to create a laminate. The laminate is then heated and pressurized to bond the components together.

[0088] Various types of solar cell modules can be exemplified. For example, a configuration in which a substrate / encapsulant / solar cell element / encapsulant / protective material is laminated in that order, with the solar cell element sandwiched between encapsulants on both sides; a configuration in which a solar cell element pre-formed on the surface of a substrate such as glass is laminated in that order, with the substrate / solar cell element / encapsulant / protective material; a configuration in which a solar cell element formed on the inner circumferential surface of a substrate, for example, an amorphous solar cell element fabricated by sputtering on a fluororesin sheet, is then coated with an encapsulant and protective material; and so on. Furthermore, since the protective material is located on the side opposite to the substrate side of the solar cell module, i.e., the bottom side, when the substrate into which sunlight enters is considered the top of the solar cell module, it is sometimes referred to as the bottom protective material or back protective material.

[0089] Examples of solar cell elements that can be used include silicon-based materials such as single-crystal silicon, polycrystalline silicon, and amorphous silicon; III-V and II-VI compound semiconductor materials such as gallium-arsenide, copper-indium-selenium, copper-indium-gallium-selenium, and cadmium-tellurium; and heterojunction types of amorphous silicon and single-crystal silicon. In a solar cell module, multiple solar cell elements are electrically connected in series, for example, via an interconnector.

[0090] The solar cell module according to the present invention includes, for example, a metal material provided adjacent to the sealing resin layer. Such a metal material is, for example, wiring, electrodes, etc. Examples of metal materials include busbar electrodes, interconnectors, and finger electrodes. Busbar electrodes, interconnects, and finger electrodes are used in modules to connect solar cell elements together and to collect the electricity they generate. The metal material includes, for example, at least one metal selected from copper, tin, lead, iron, bismuth, aluminum, and silver.

[0091] Examples of substrates constituting the solar cell module according to the present invention include glass substrates, acrylic resin substrates, polycarbonate substrates, polyester substrates, fluorine-containing resin substrates, and the like. The protective material (lower protective material) may be a single or multilayer sheet of metal, various inorganic materials, or various thermoplastic resin films. For example, a single or multilayer sheet made of metals such as tin, aluminum, or stainless steel, inorganic materials such as glass, polyester, inorganic vapor-deposited polyester, fluorine-containing resin, or thermoplastic resin film such as polyolefin can be exemplified. The solar cell encapsulant according to the present invention exhibits good adhesion to these substrates or protective materials.

[0092] The method for manufacturing the solar cell module according to the present invention is not particularly limited, and conventionally known manufacturing methods such as the nip roll method, autoclave method, vacuum bag method, and vacuum laminator method can be used. Manufacturing may be carried out using one of these methods, or two or more manufacturing methods may be combined. Among these, the manufacturing method using a vacuum laminator is preferred as the manufacturing method for the solar cell module according to the present invention. One method using a vacuum laminator involves, for example, sandwiching the solar cell encapsulant and solar cell elements according to the present invention between a substrate and a protective material to obtain a laminate. This laminate is then heated and degassed in a double vacuum apparatus, and in a pressurizing process, a diaphragm rubber is heat-compressed onto the laminate from above the double vacuum by heating and pressurizing the laminate to obtain a solar cell module.

[0093] The embodiments of the present invention have been described above, but these are merely examples, and various other configurations can also be adopted. Furthermore, the present invention is not limited to the embodiments described above, and any modifications, improvements, etc., that can achieve the objectives of the present invention are included in the present invention. [Examples]

[0094] This embodiment will be described in detail below with reference to examples and other relevant information. However, this embodiment is not limited in any way to the descriptions of these examples.

[0095] [material] The following components were used. Here, the melt flow rate (MFR) was measured in accordance with JIS K 7210:1999 under conditions of 190°C and a 2160g load. The Vicat softening point was measured in accordance with JIS K 7206:1999.

[0096] <Ethylene-unsaturated ester copolymer (A)> • EVA1: Ethylene-vinyl acetate copolymer (67% by mass of constituent units derived from ethylene, 33% by mass of constituent units derived from vinyl acetate, MFR (190℃, 2160g load) 14g / 10min) • EVA2: Ethylene-vinyl acetate copolymer (72% by mass of constituent units derived from ethylene, 28% by mass of constituent units derived from vinyl acetate, MFR (190℃, 2160g load) 15g / 10min) • EVA3: Ethylene-vinyl acetate copolymer (contains 81% by mass of constituent units derived from ethylene, 19% by mass of constituent units derived from vinyl acetate, MFR (190℃, 2160g load) 15g / 10min) • EVA4: Ethylene-vinyl acetate copolymer (contains 81% by mass of constituent units derived from ethylene, 19% by mass of constituent units derived from vinyl acetate, MFR (190℃, 2160g load) 150g / 10min) The content of constituent units derived from vinyl acetate was measured in accordance with JIS K 7192:1999. The content of constituent units derived from ethylene was determined by subtracting the content of constituent units derived from vinyl acetate from the total content of constituent units derived from ethylene and vinyl acetate, which was set to 100% by mass.

[0097] <Epoxy group-containing ethylene copolymer (B)> • EMAGMA1: Ethylene-methyl acrylate-glycidyl methacrylate copolymer (67% by mass of constituent units derived from ethylene, 27% by mass of constituent units derived from methyl acrylate, 6% by mass of constituent units derived from glycidyl methacrylate, manufactured by Sumitomo Chemical Co., Ltd., Bondfast 7M (product name), MFR (190℃, 2160g load): 7g / 10min, melting point: 52℃, Vicat softening point: less than 25℃) • EMAGMA2: Ethylene-methyl acrylate-glycidyl methacrylate copolymer (70% by mass of constituent units derived from ethylene, 27% by mass of constituent units derived from methyl acrylate, 3% by mass of constituent units derived from glycidyl methacrylate, manufactured by Sumitomo Chemical Co., Ltd., Bond First 7L (product name), MFR (190℃, 2160g load): 7g / 10min, melting point: 60℃, Vicat softening point: less than 25℃) • EVAGMA1: Ethylene-vinyl acetate-glycidyl methacrylate copolymer (contains 83% by mass of constituent units derived from ethylene, 5% by mass of constituent units derived from vinyl acetate, and 12% by mass of constituent units derived from glycidyl methacrylate; manufactured by Sumitomo Chemical Co., Ltd., Bondfast 7B (product name), MFR (190℃, 2160g load): 7g / 10min, melting point: 95℃, Vicat softening point: 66℃) Furthermore, the melting point of epoxy group-containing ethylene copolymer (B) was measured in accordance with JIS K 7121-1987.

[0098] <Silane coupling agent> • Silane coupling agent 1: 3-methacryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM503 (product name))

[0099] <Organic peroxide> • Organic peroxide 1:2,5-dimethyl-2,5-di(t-butylperoxy)hexane (manufactured by Arkema Yoshitomi Co., Ltd., Luperox 101 (trade name))

[0100] <Ionomer (C)> • Ionomer 1: Mg ionomer of ethylene-methacrylic acid copolymer (container content of ethylene-derived components: 80% by mass, content of methacrylic acid-derived components: 20% by mass, degree of neutralization: 44%, MFR (190℃, 2160g load): 2.5g / 10min)

[0101] [Examples 1-2 and Comparative Examples 1-3] The mixture was pre-mixed according to the proportions shown in Table 1, fed into a 30 mmφ single-screw extruder equipped with a pelletizer (manufactured by Thermoplastics, machine number: 53-103), and melt-kneaded under the extrusion or melt-kneading conditions described below, followed by granulation to obtain pellets of the adhesive resin composition. The extrusion conditions for the above single-screw extruder are as follows: L / D: 28 Barrel temperature (°C): C1 (80), C2 (115), C3 (135), C4 (135), C5 (135), D (130) Screw rotation speed: 45 rpm Extrusion rate: 3.5 kg / h Screen mesh: 60 / 120 / 60

[0102] [Examples 3-4] The mixture was pre-mixed according to the proportions shown in Table 1, fed into a 40 mmφ single-screw extruder equipped with a pelletizer (manufactured by Nakatani Machinery Co., Ltd., machine number: VSK40), and melt-kneaded under the extrusion or melt-kneading conditions described below, followed by granulation to obtain pellets of the adhesive resin composition. Here, the amount (parts by mass) of the silane coupling agent and organic peroxide in Example 4 is the value when the total amount of ethylene-unsaturated ester copolymer (A) and epoxy group-containing ethylene copolymer (B) is 100 parts by mass. The silane coupling agent and organic peroxide were impregnated into the ethylene-unsaturated ester copolymer (A) and epoxy group-containing ethylene copolymer (B), and then melt-kneaded. The extrusion conditions in the single-screw extruder described above are as follows. Screw: Dalmaid screw tip L / D: 28 Barrel temperature (°C): C1 (120), C2 (160), C3 (180), C4 (200), D (160) Screw rotation speed: 45 rpm Extrusion rate: 10 kg / h Screen mesh: 60 / 120 / 60

[0103] <Evaluation of the optical properties of adhesive resin compositions> (1) Creating the sheet The obtained adhesive resin composition was pressed using a hydraulic hot press (manufactured by Toho Machinery Co., Ltd., machine number: TBDM50-2) at 140°C and 9.8 MPa, and then cooled at 20°C and 14.7 MPa to produce a 3 mm thick press sheet.

[0104] (2) Measurement of haze Using the obtained press sheets, the haze was measured in accordance with JIS K 7136:2000 using a haze meter (manufactured by Suga Test Instruments Co., Ltd., product name: HZ-V3). The haze was evaluated according to the following criteria. The evaluation results are shown in Table 1. (Hayes's evaluation criteria) A (Excellent): Haze is 10% or less B (Good): Haze is between 10% and 20%. C (Poor): Haze exceeds 20%

[0105] (3) Measurement of total light transmittance The obtained press sheets were used to measure the total light transmittance using a haze meter (manufactured by Suga Test Instruments Co., Ltd., product name: HZ-V3) in accordance with JIS K 7361-1:1997. The total light transmittance was evaluated according to the following criteria. The evaluation results are shown in Table 1. (Evaluation criteria for total light transmittance) In evaluating the 3mm thick press sheet produced by the above method, A (Excellent): Total light transmittance is 90% or higher. B (Good): Total light transmittance is 70% or more but less than 90% C (Poor): Total light transmittance is less than 70%

[0106] (3) Measurement of the Yellow Index (YI) Using the obtained press sheets, the YI (transmission method) was measured using a colorimeter (CC-iS, manufactured by Suga Test Instruments Co., Ltd.) in accordance with JIS K 7373:2006. The YI was evaluated according to the following criteria. The evaluation results are shown in Table 1. (YI's evaluation criteria) A (Excellent): YI is 3 or less B (Good): YI is greater than 3 and less than or equal to 5. C (Defective): YI exceeds 5

[0107] [Table 1]

[0108] As is clear from Table 1, the press sheets prepared using the adhesive resin compositions of Examples 1 to 4 exhibited excellent haze, total light transmittance, and YI, and thus had superior transparency. In contrast, the press sheet prepared using the adhesive resin composition of Comparative Example 1, which had an ethylene content difference of 16% by mass, had poor haze, total light transmittance, and YI, and thus poor transparency. The press sheet prepared using the adhesive resin composition of Comparative Example 2, which had an ethylene content difference of 11% by mass, had poor haze and YI, and thus poor transparency. The press sheet prepared using the adhesive resin composition of Comparative Example 3, which had an unsaturated ester content of less than 20% by mass in the ethylene-unsaturated ester copolymer, had poor YI and thus poor transparency. From the above, it was confirmed that transparency can be improved with the adhesive resin composition according to the present invention.

[0109] [Examples 5-6 and Comparative Examples 4-5] The adhesive resin composition obtained in Example 3 is referred to as Adhesive Resin Composition 1. The adhesive resin composition obtained in Example 4 is referred to as Adhesive Resin Composition 2.

[0110] EVA3:25% by mass, EVA4:25% by mass, EVAGMA1:50% by mass, silane coupling agent:1.5 parts by mass, and organic peroxide:0.3 parts by mass were pre-mixed and fed into a 40 mmφ single-screw extruder (manufactured by Nakatani Machinery Co., Ltd.) equipped with a pelletizer. The mixture was melt-kneaded under the following extrusion or melt-kneading conditions, and granulated to obtain pellets of adhesive resin composition. Here, the amounts (parts by mass) of silane coupling agent and organic peroxide are values ​​when the total amount of ethylene-unsaturated ester copolymer (A) and epoxy group-containing ethylene copolymer (B) is 100 parts by mass. The extrusion conditions in the single-screw extruder are as follows. The obtained adhesive resin composition is referred to as adhesive resin composition 3. Screw: Dalmaid screw tip L / D: 28 Barrel temperature (°C): C1 (120), C2 (160), C3 (180), C4 (200), D (160) Screw rotation speed: 45 rpm Extrusion rate: 10 kg / h Screen mesh: 60 / 120 / 60

[0111] The mixtures were pre-mixed according to the proportions shown in Table 2, fed into a 40mmφ T-die sheet molding machine (manufactured by Nakatani Machinery Co., Ltd., machine number: VSK40), and melt-kneaded under the extrusion or melt-kneading conditions described below. Sheets made of adhesive resin compositions with thicknesses of 100 μm and 300 μm were then produced by extrusion sheet molding. The extrusion conditions for the above T-die sheet molding machine were as follows: Screw: Tip-damaged double flight L / D: 26 Barrel temperature (°C): C1 (80), C2 (100), C3 (120), A (120), D1 (120), D2 (120), D3 (120) Screw rotation speed: 45 rpm Screen mesh: 60

[0112] <Evaluation of the optical properties of glass laminates> (1) Fabrication of glass laminates Using a vacuum heating laminating machine (double vacuum chamber laminating machine, manufactured by NPC Corporation, product name: LM-50×50S), glass, ionomer 1, and a sheet made of the adhesive resin composition with a thickness of 100 μm were laminated in this order, and the layers were bonded at a heating temperature of 140°C, a heating pressure of 1 atm, and a heating time of 20 minutes. After that, the laminate was wrapped in bleached cloth and left to stand in the air, and slowly cooled by natural cooling to produce a glass laminate for optical property evaluation. Glass laminate composition: Glass (3.2 mm thick) / Ionomer 1 (1500 μm thick) / Sheet made of adhesive resin composition (100 μm thick) / Glass (3.2 mm thick)

[0113] (2) Measurement of haze The obtained glass laminate was used to measure the haze using a haze meter (manufactured by Suga Test Instruments Co., Ltd., product name: HZ-V3) in accordance with JIS K 7136:2000. The haze was evaluated according to the following criteria. The evaluation results are shown in Table 2. (Hayes's evaluation criteria) A (Excellent): Haze is 5% or less B (Good): Haze exceeds 5% and is 10% or less C (Poor): Haze exceeds 10%

[0114] (3) Measurement of total light transmittance Using the obtained glass laminate, the total light transmittance was measured with a haze meter (manufactured by Suga Test Instruments Co., Ltd., product name: HZ-V3 type) in accordance with JIS K 7361-1:1997. The total light transmittance was evaluated according to the following criteria respectively. The evaluation results are shown in Table 2. (Evaluation criteria for total light transmittance) A (Excellent): Total light transmittance is 85% or more B (Good): Total light transmittance is 80% or more and less than 85% C (Poor): Total light transmittance is less than 80%

[0115] (4) Measurement of yellow index (YI) Using the obtained glass laminate, in accordance with JIS K 7373:2006, YI (transmission method) was measured using a colorimeter (manufactured by Suga Test Instruments Co., Ltd., CC-iS). YI was evaluated according to the following criteria. The evaluation results are shown in Table 2. (Evaluation criteria for YI) A (Excellent): YI is 3 or less B (Good): YI exceeds 3 and is 5 or less C (Poor): YI exceeds 5

[0116] (Adhesion evaluation to PET film) Using a vacuum heating laminator (double vacuum chamber laminator, manufactured by NPC Co., Ltd., product name: LM-50×50S), glass (non-tin surface as the adhesive surface), a sheet made of the above adhesive resin composition with a thickness of 300 μm, and a PET film with a thickness of 100 μm (untreated by corona) were laminated in this order, and laminated at a heating temperature of 140 °C, a pressure of 1 atm during heating, and a heating time of 60 minutes to produce a glass laminate. Then, the laminate was left standing in the atmosphere and gradually cooled by natural cooling. Composition of the glass laminate: Glass (3.9 mm thick) / Sheet made of adhesive resin composition (300 μm thick) / PET film (100 μm thick) A 15 mm wide slit was made in the sheet portion of the obtained glass laminate to create a test specimen, which was then placed on a tensile testing machine. The PET film was peeled off at a tensile speed of 100 mm / min and a peel angle of 180°, and the average stress was determined as the initial adhesive strength (N / 15 mm).

[0117] The glass laminate was stored at 85°C and 90% relative humidity. The adhesive strength of the glass laminate after 500 hours of storage and after 1000 hours of storage were also determined. The obtained adhesive strengths were defined as the adhesive strength of each glass laminate to the PET film. The adhesion to the PET film was evaluated according to the following criteria. The measurement results are shown in Table 2. (Evaluation criteria for adhesion to PET film) A (Excellent): Adhesion strength to PET film is 15N / 15mm or higher at initial stage, after 500 hours, and after 1000 hours. B (Defective): The adhesive strength to the PET film is less than 15N / 15mm at one or more of the following times: initial, after 500 hours, and after 1000 hours.

[0118] <Evaluation of adhesion to glass> Using a vacuum heating laminating machine (double vacuum chamber laminating machine, manufactured by NPC Corporation, product name: LM-50×50S), glass (with the non-tin side as the bonding surface) and a sheet made of the adhesive resin composition with a thickness of 300 μm were laminated in this order, and a glass laminate was fabricated by laminating them at a heating temperature of 140°C, a heating pressure of 1 atm, and a heating time of 60 minutes. After that, the glass laminate was left to stand in the air and slowly cooled by natural cooling. Glass laminate composition: Glass (3.9 mm thick) / Sheet made of adhesive resin composition (300 μm thick) A 15 mm wide slit was made in the sheet portion of the obtained glass laminate to create a test specimen, which was then placed on a tensile testing machine. The glass (3.9 mm thick) and the sheet (300 μm thick) made of the adhesive resin composition were peeled apart at a tensile speed of 100 mm / min and a peel angle of 180°, and the average stress was determined as the initial adhesive strength (N / 15 mm).

[0119] The glass laminate was stored at 85°C and 90% relative humidity. The adhesive strength of the glass laminate after 500 hours and after 1000 hours was also determined. The obtained adhesive strengths were defined as the adhesive strength to glass for each glass laminate. The adhesion to glass was evaluated according to the following criteria. The measurement results are shown in Table 2. (Evaluation criteria for adhesion to glass) A (Excellent): Adhesion strength to glass is 20N / 15mm or higher at initial stage, after 500 hours, and after 1000 hours. B (Defective): The adhesive strength to the glass is less than 20 N / 15 mm at one or more of the following times: initial, after 500 hours, or after 1000 hours.

[0120] [Table 2]

[0121] As is clear from Table 2, the laminated glass layers prepared using the adhesive resin compositions of Examples 5 and 6 exhibited excellent transparency, with superior haze, total light transmittance, and YI. Furthermore, they also showed excellent adhesion to both PET film and glass. In contrast, the glass laminate prepared using the adhesive resin composition of Comparative Example 4, which had an ethylene content difference of 15.3% by mass, exhibited poor haze and inferior transparency. The glass laminate prepared using the adhesive resin composition of Comparative Example 5, which did not contain epoxy group-containing ethylene copolymer (B), showed poor adhesion to both PET film and glass, resulting in inferior adhesion. From the above, it was confirmed that the adhesive resin composition according to the present invention improves transparency and adhesion to the polyester resin layer. Such glass laminates can be used, for example, in laminated glass or solar cell modules.

[0122] This application claims priority based on Japanese Patent Application No. 2022-040794, filed on 15 March 2022, and incorporates all of its disclosures herein.

Claims

1. An ionomer resin layer containing an ionomer (C) of an ethylene-unsaturated carboxylic acid copolymer, An adhesive resin layer comprising an adhesive resin composition containing an ethylene-unsaturated ester copolymer (A) and an epoxy group-containing ethylene-based copolymer (B) (excluding the ethylene-unsaturated ester copolymer (A)), A polyester resin layer containing polyester resin (D), These should be provided in this order. The content of constituent units derived from unsaturated esters in the ethylene-unsaturated ester copolymer (A) is more than 20% by mass relative to the total constituent units of the ethylene-unsaturated ester copolymer (A). The content of ethylene-derived constituent units relative to the total constituent units of the ethylene-unsaturated ester copolymer (A) (X １ ) and the content of ethylene-derived constituent units relative to the total constituent units of the epoxy group-containing ethylene copolymer (B) (X ２ ) difference (X １ -X ２ A laminated glass interlayer in which the absolute value of ) is 6% by mass or less.

2. The laminated glass interfilm according to claim 1, wherein the melt flow rate of the ethylene-unsaturated ester copolymer (A), measured under conditions of 190°C and a 2160 g load in accordance with JIS K 7210:1999, is 1 g / 10 min or more and 100 g / 10 min or less.

3. The laminated glass interfilm according to claim 1, wherein the ethylene-unsaturated ester copolymer (A) comprises an ethylene-vinyl acetate copolymer.

4. The laminated glass interfilm according to claim 1, wherein the epoxy group-containing ethylene copolymer (B) comprises at least one selected from the group consisting of ethylene-(meth)acrylate glycidyl copolymer, ethylene-(meth)acrylate glycidyl vinyl acetate copolymer, and ethylene-(meth)acrylate glycidyl (meth)acrylate ester copolymer.

5. The laminated glass interfilm according to claim 1, wherein the content of ethylene-derived structural units in the epoxy group-containing ethylene copolymer (B) is 82% by mass or less relative to the total structural units constituting the epoxy group-containing ethylene copolymer (B).

6. The laminated glass interfilm according to claim 1, wherein the epoxy group-containing ethylene copolymer (B) has a Vicat softening point of 65°C or less as defined in JIS K 7206:1999.

7. The laminated glass interfilm according to claim 1, wherein the epoxy group-containing ethylene copolymer (B) has a melting point of 90°C or less, as measured in accordance with JIS K 7121-1987.

8. The laminated glass interlayer according to claim 1, wherein the haze measured by the method described below is 10% or less. (method) The adhesive resin composition is pressed at 140°C and 9.8 MPa, then cooled at 20°C and 14.7 MPa to produce a press sheet with a thickness of 3 mm. Next, the haze of the obtained press sheet is measured using a haze meter in accordance with JIS K 7136:2000.

9. The laminated glass interlayer according to claim 1, wherein when the total content of the ethylene-unsaturated ester copolymer (A) and the epoxy group-containing ethylene copolymer (B) is 100% by mass, the content of the ethylene-unsaturated ester copolymer (A) is 40% by mass or more and 99% by mass or less.

10. The laminated glass interfilm according to claim 1, wherein the total content of the ethylene-unsaturated ester copolymer (A) and the epoxy group-containing ethylene copolymer (B) is 70% by mass or more and 100% by mass or less when the total amount of the adhesive resin composition is considered to be 100% by mass.

11. The laminated glass interlayer according to claim 1, wherein the haze measured by the method described below is 5% or less. (method) A 3.2 mm thick glass, a 1500 μm thick ionomer resin layer, and a 100 μm thick sheet of the adhesive resin composition are laminated in this order, and the 3.2 mm thick glass is bonded together at a heating temperature of 140°C, a heating pressure of 1 atm, and a heating time of 20 minutes. The laminate is slowly cooled by natural cooling to produce a glass laminate for optical property evaluation. Next, the haze of the obtained glass laminate is measured using a haze meter in accordance with JIS K 7136:2000.

12. The laminated glass interlayer according to claim 1, wherein the adhesive strength to the PET film measured by the method described below is 15 N / 15 mm or more at the initial stage, after 500 hours, and after 1000 hours. (method) A glass laminate is prepared by laminating a 3.9 mm thick glass (non-tin side as the bonding surface), a 300 μm thick sheet of the adhesive resin composition, and a 100 μm thick PET film (untreated with corona) in this order, and bonding them together at a heating temperature of 140°C, a heating pressure of 1 atm, and a heating time of 60 minutes. The glass laminate is then left to stand in the air and cooled slowly by natural cooling. A 15 mm wide slit is made in the sheet portion of the obtained glass laminate to create a test specimen, which is then placed on a tensile testing machine. The PET film is peeled off at a tensile speed of 100 mm / min and a peeling angle of 180°, and the mean stress is determined as the initial adhesive strength (N / 15 mm). The glass laminate is stored at 85°C and 90% relative humidity, and the adhesive strength of the glass laminate after 500 hours of storage and after 1000 hours of storage are also determined.

13. The laminated glass interlayer according to claim 1, wherein the adhesive strength to the PET film after 1,000 hours of storage, as measured by the method described below, is 50 N / 15 mm or more. (method) A glass laminate is prepared by laminating a 3.9 mm thick glass (non-tin side as the bonding surface), a 300 μm thick sheet of the adhesive resin composition, and a 100 μm thick PET film (untreated with corona) in this order, and bonding them together at a heating temperature of 140°C, a heating pressure of 1 atm, and a heating time of 60 minutes. The glass laminate is then left to stand in the air and allowed to cool slowly by natural cooling. Next, the glass laminate is stored for 1000 hours at 85°C and 90% relative humidity. A 15 mm wide slit is made in the sheet portion of the obtained glass laminate to create a test specimen, which is then placed on a tensile testing machine. The PET film is peeled off at a tensile speed of 100 mm / min and a peeling angle of 180°, and the mean stress is determined as the adhesive strength (N / 15 mm) to the PET film after 1000 hours of storage.

14. The ionomer resin layer and the adhesive resin layer are adjacent to each other. The laminated glass interfilm according to any one of claims 1 to 13, wherein the polyester resin layer is adjacent to the side of the adhesive resin layer opposite to the side adjacent to the ionomer resin layer.

15. A laminated glass interlayer according to any one of claims 1 to 13, Transparent plate-shaped members provided on both sides of the laminated glass interlayer, Laminated glass with the following features.

16. The laminated glass according to claim 15, comprising at least one configuration in which the transparent plate-like member and the ionomer resin layer are adjacent to each other.

17. An ionomer resin layer containing an ionomer (C) of an ethylene-unsaturated carboxylic acid copolymer, An adhesive resin layer comprising an adhesive resin composition containing an ethylene-unsaturated ester copolymer (A) and an epoxy group-containing ethylene-based copolymer (B) (excluding the ethylene-unsaturated ester copolymer (A)), A polyester resin layer containing polyester resin (D), These should be provided in this order. The content of constituent units derived from unsaturated esters in the ethylene-unsaturated ester copolymer (A) is more than 20% by mass relative to the total constituent units of the ethylene-unsaturated ester copolymer (A). The content of ethylene-derived constituent units relative to the total constituent units of the ethylene-unsaturated ester copolymer (A) (X １ ) and the content of ethylene-derived constituent units relative to the total constituent units of the epoxy group-containing ethylene copolymer (B) (X ２ ) difference (X １ -X ２ A solar cell encapsulant in which the absolute value of ) is 6% by mass or less.

18. Solar cell element and A sealing resin layer made of the solar cell sealing material according to claim 17 for sealing the solar cell element, A solar cell module equipped with the following features.

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