JP2014237796A - (meth)acrylic resin composition, molded article, optical member, solar cell top sheet and solar cell module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a molded article having a high total ray transmittance, a sufficiently low haze and a high tensile elastic modulus, a (meth)acrylic resin composition for obtaining the molded article, and a solar cell module having good power generation efficiency by using the molded article as an optical member of a solar cell top sheet.SOLUTION: The (meth)acrylic resin composition comprises 100 parts by mass of a (meth)acrylic resin (A), 5 to 40 parts by mass of glass (B), and 0.1 to 20 parts by mass of a benzoate (C). The molded article is obtained by molding the (meth)acrylic resin composition. Also disclosed are: an optical member using the molded article; a solar cell top sheet using the optical member; and a solar cell module using the solar cell top sheet.

Description

The present invention relates to a (meth) acrylic resin composition, a molded body, an optical member, a solar cell top sheet, and a solar cell module.

  Conventionally, a glass material is used for a top sheet member of a solar cell. A top sheet member using a glass material has an advantage of excellent dimensional stability and the like, but there is a limit to weight reduction. Then, using resin material for a solar cell top sheet is examined. By adopting a molded body obtained from a composite resin obtained by adding a filler such as an inorganic filler to a resin, various properties such as rigidity and dimensional stability are improved.

  For example, it is disclosed that a molded body obtained by adding a glass filler to (meth) acrylic resin is used for a solar cell top sheet (Patent Document 1).

International Publication No. 2012 / 093,717

  However, although the molded body obtained in Patent Document 1 has a high total light transmittance, it cannot be said that the haze is sufficiently low. Therefore, when this molded body is applied to the solar cell top sheet, the power generation efficiency of the solar cell module is not sufficient.

  An object of the present invention is to provide a molded article having a high total light transmittance, a sufficiently low haze, and a high tensile elastic modulus, and a (meth) acrylic resin composition for obtaining the molded article.

  Moreover, the objective of this invention is providing the solar cell module with favorable electric power generation efficiency by using the molded object of this invention as an optical member of a solar cell top sheet.

The above problems are solved by the following inventions [1] to [8].
[1] A (meth) acrylic resin composition containing 100 parts by weight of (meth) acrylic resin (A), 5 to 40 parts by weight of glass (B) and 0.1 to 20 parts by weight of benzoic acid ester (C).
[2] The (meth) acrylic resin composition according to [1], wherein the glass (B) is a scaly glass.
[3] The (meth) acrylic resin composition according to [2], wherein the glass flakes have a particle diameter of 100 to 2,000 μm and an aspect ratio of 15 or more.
[4] The (meth) described in any one of [1] to [3], wherein the absolute value of the difference between the refractive index of the (meth) acrylic resin (A) and the refractive index of the glass (B) is 0.08 or less. Acrylic resin composition.
[5] A molded product obtained by molding the (meth) acrylic resin composition according to any one of [1] to [4].
[6] An optical member using the molded article according to [5].
[7] A solar cell top sheet using the optical member according to [6].
[8] A solar cell module using the solar cell top sheet according to [7].

  Since the molded article of the present invention is excellent in total light transmittance, haze and tensile modulus, it can be used outdoors such as transparent plates, electronic and electrical equipment casings, sound insulation boards, signboards, light collecting equipment, roof members, etc. Panel member used, optical lens, plastic substrate for liquid crystal display element, substrate for color filter, plastic substrate for organic EL display element, plant factory member, solar cell substrate, solar cell top sheet member, touch panel, optical element, optical waveguide, It is suitable for various uses such as optical members such as LED sealing materials.

Sectional drawing which shows one embodiment of the solar cell module of this invention Sectional drawing which shows one embodiment of the solar cell module of this invention

<(Meth) acrylic resin (A)>
The (meth) acrylic resin (A) is a component contained in the (meth) acrylic resin composition of the present invention.

  The (meth) acrylic resin (A) is preferably one containing 50% by mass or more of a methacrylic acid ester unit from the viewpoint of moldability, weather resistance, heat resistance, mechanical properties and optical properties, and 70 mass% of a methacrylic acid ester unit. %, More preferably those containing 90% by mass or more of methacrylic acid ester units.

  Examples of the methacrylic acid ester include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate and tert-butyl methacrylate, and formability and weather resistance. From the viewpoint of heat resistance, mechanical properties and optical properties, methyl methacrylate is preferred.

  The resin containing methyl methacrylate units contains 50 to 99.9% by mass of methyl methacrylate units and 0.1 to 50% by mass of copolymerizable monomer units from the viewpoint of excellent optical properties and light resistance. More preferred are those containing methyl methacrylate units of 60 to 99.9% by mass and copolymerizable monomer units of 0.1 to 40% by mass, and methyl methacrylate units of 70 to 99.9% by mass. % And those containing 0.1 to 30% by mass of copolymerizable monomer units are more preferred.

  Examples of monomers copolymerizable with methyl methacrylate include, for example, methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, Acrylic esters such as hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, benzyl acrylate, etc .; ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate And methacrylic acid esters other than methyl methacrylate such as tert-butyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, benzyl methacrylate; vinyl acetate; styrene, -Aromatic vinyl monomers such as methylstyrene, o-methylstyrene, m-methylstyrene, α-methylstyrene, vinylnaphthalene; vinyl cyanide compounds such as acrylonitrile and methacrylonitrile; acrylic acid, methacrylic acid, crotonic acid Α, β-unsaturated carboxylic acids such as N; and maleimide compounds such as N-ethylmaleimide and N-cyclohexylmaleimide. These can be used alone or in combination of two or more.

  In this invention, what introduce | transduced the benzoic acid ester residue into the structure of (meth) acrylic resin (A) can be used as (meth) acrylic resin (A) as needed.

The weight average molecular weight (Mw) of the (meth) acrylic resin (A) is preferably from 30,000 to 500,000 from the viewpoint of moldability and mechanical properties of the (meth) acrylic resin composition of the present invention. The lower limit of Mw of the (meth) acrylic resin (A) is more preferably 40,000 or more, and further preferably 70,000 or more. The upper limit of Mw of the (meth) acrylic resin (A) is more preferably 300,000 or less, and still more preferably 150,000 or less.

<Glass (B)>
Glass (B) is a component contained in the (meth) acrylic resin composition of the present invention.

  Examples of the glass (B) include E glass, C glass, A glass, S glass, D glass, NE glass, T glass, quartz, low dielectric constant glass, and high dielectric constant glass.

  Examples of the glass (B) include long glass fibers, short glass fibers, glass beads, glass cloth, and scaly glass, and scaly glass is preferable in terms of excellent optical properties.

  The number average particle size of the flaky glass is preferably 100 to 2,000 μm. The number average particle diameter of the glass flakes is 100 μm or more, and the molded product of the present invention tends to have good translucency, and the molded product of the present invention tends to be excellent when the molded product of the present invention is obtained at 1,000 μm or less. . The upper limit of the number average particle size of the glass flakes is more preferably 1,000 μm or less, and even more preferably 600 μm or less.

  In the present invention, the number average particle size of the glass flakes is a value obtained using a particle size distribution measuring device (trade name: LA-910, manufactured by Horiba, Ltd.).

  The aspect ratio of the scaly glass is preferably 15 or more. Here, the aspect ratio is a value obtained by dividing the number average particle diameter of the glass flakes by the average thickness of the glass flakes.

  As glass (B), the absolute value of the difference from the refractive index of (meth) acrylic resin (A) is preferably 0.08 or less, and more preferably 0.04 or less. The absolute value of the difference between the refractive index of the (meth) acrylic resin (A) and the refractive index of the glass (B) is 0.08 or less, and the optical properties of the molded article of the present invention tend to be excellent.

  Examples of the glass (B) whose absolute value of the difference from the refractive index of the (meth) acrylic resin (A) is 0.08 or less include C glass, T glass, and NE glass.

Specific examples of the glass (B) include “Glass Flakes” (trade name) manufactured by Nippon Sheet Glass Co., Ltd.

<Benzoic acid ester (C)>
Benzoic acid ester (C) is a component contained in the acrylic resin composition of the present invention.

  Examples of the benzoic acid ester (C) include dipropylene glycol dibenzoate, triethylene glycol dibenzoate, polyethylene glycol dibenzoate, pentaerythritol tetrabenzoate, glycerol tribenzoate, and 1,4-cyclohexanedimethanol dibenzoate.

The benzoic acid ester (C) is preferably one having excellent compatibility with the (meth) acrylic resin (A) component in terms of the haze of the molded article of the present invention.

<(Meth) acrylic resin composition>
The (meth) acrylic resin composition of the present invention contains (meth) acrylic resin (A), glass (B) and benzoic acid ester (C).

  The compounding quantity of the glass (B) in a (meth) acrylic resin composition is 5-40 mass parts with respect to 100 mass parts of (meth) acrylic resin (A). When the content of the glass (B) is 5 parts by mass or more, the strength of the molded product of the present invention is excellent, and when it is 40 parts by mass or less, the moldability when obtaining the molded product of the present invention is excellent. As for the lower limit of the compounding quantity of glass (B), 10 mass parts or more are preferable. Moreover, 30 mass parts or less is preferable and, as for the upper limit of the compounding quantity of glass (B), 20 mass parts or less are more preferable.

  The compounding quantity of the benzoic acid ester (C) in a (meth) acrylic resin composition is 0.1-20 mass parts with respect to 100 mass parts of (meth) acrylic resin (A). When the content of the benzoic acid ester (C) is 0.1 parts by mass or more, the molded article of the present invention is excellent in optical properties, and when it is 20 parts by mass or less, the moldability in obtaining the molded article of the present invention is excellent. 0.5 mass parts or more is preferable and, as for the lower limit of the compounding quantity of benzoic acid ester (C), 1 mass part or more is more preferable. Further, the upper limit of the amount of benzoate ester (C) is preferably 15 parts by mass or less.

  In the (meth) acrylic resin composition, various additives such as an ultraviolet absorber, a flame retardant, and an ultraviolet absorber can be added as necessary. Moreover, in this invention, the additive which introduce | transduced the benzoic acid ester residue into the structure of the additive can be used as needed.

  Examples of the method for obtaining the (meth) acrylic resin composition include a method of melt-kneading a mixture containing the (meth) acrylic resin (A), glass (B) and benzoic acid ester (C).

  Examples of the apparatus used for melt kneading include, for example, ribbon blenders, tumblers, nauter mixers, Henschel mixers, super mixers, planetary mixers and other premixers and Banbury mixers, kneaders, rolls, kneader ruders, single screw extruders, A melt kneader such as a twin screw extruder may be used.

  Examples of the form of the (meth) acrylic resin composition include powder and pellets.

The size of the pellet is preferably about 1 to 10 mm, more preferably about 1 to 5 mm, from the viewpoint of ease of handling and molding of the pellet.

<Molded body>
The molded product of the present invention is a molded product obtained by molding a (meth) acrylic resin composition.

Examples of the molding method of the molded body include an injection molding method, an extrusion molding method, and a compression molding method.

<Optical member>
The optical member of the present invention is an optical member using the molded article of the present invention.

  Examples of the optical member include a transparent plate, an optical lens, a liquid crystal display element plastic substrate, a color filter substrate, an organic EL display element plastic substrate, a solar cell substrate, a solar cell top sheet member, a touch panel, an optical element, and an optical waveguide. And LED encapsulant.

  The shape and composition of the optical member used for the solar cell top sheet is not particularly limited as long as the solar cell can transmit sufficient light to generate power.

As an optical member used for a solar cell top sheet, what provided the uneven structure, what has a curvature, and a film-like thing are mentioned, for example.

<Solar cell top sheet>
The solar cell top sheet of the present invention is a solar cell top sheet using the optical member of the present invention.

<Solar cell module>
The solar cell module of the present invention uses a solar cell top sheet.

  The configuration of the solar cell module is not particularly limited as long as the solar cell can generate power.

  One embodiment of the solar cell module of the present invention is shown in FIG. As for the solar cell module 1, the solar cell top sheet 2, the sealing material 3, the solar cell 4, and the back sheet 5 which used the optical member of this invention are laminated | stacked in order.

  Another embodiment of the solar cell module of the present invention is shown in FIG. As for the solar cell module 1, the solar cell topsheet 2, the sealing material 3, and the photovoltaic cell 4 which used the optical member of this invention are laminated | stacked in order.

Hereinafter, the present invention will be described by way of examples. The molded body was evaluated by the following method. In the following, “part” means “part by mass”.
(A) Haze and total light transmittance Using a haze meter NDH2000 (manufactured by Nippon Denshoku Industries Co., Ltd., trade name) for a molded product having a thickness of 2 mm, the haze (unit:%) and the total with a D65 light source The light transmittance (unit:%) was measured.
(B) Tensile elastic modulus The tensile elastic modulus of a dumbbell No. 1 type test piece prepared according to JIS K7113 is measured using a Tensilon universal testing machine RTC-1250A (product name, manufactured by Orientec Co., Ltd.), and the distance between chucks. Evaluation was performed under the conditions of 115 mm and a tensile speed of 50 mm / min.
(C) Maximum power value of solar cell module Measurement of the maximum power value of the solar cell module manufactured according to the procedure of [Manufacturing method 1] below is performed using a solar simulator (manufactured by NPC Corporation). The test was performed under the condition of an intensity of 1,000 W / m ^{2 in} an environment of 25 ° C.

[Manufacturing Method 1] Solar Cell Module A laminate of the following materials (1) to (5) in sequence is formed into two glass cloth sheets for release each having a length of 500 mm in length (Honda Sangyo Co., Ltd., Honda Sandwich with flow fabric). This is installed on a hot plate of a solar cell module laminator (LM-50X50-S, manufactured by NPC Co., Ltd.), heated at 135 ° C. for 15 minutes under vacuum, and pressure-bonded at 10.3 kPa. To obtain a solar cell module.
(1) Top sheet member: 150 mm long and horizontal length sheet (2) Sealing member: 150 mm long and horizontal length 0.45 mm ethylene / vinyl acetate copolymer sheet (manufactured by CI Kasei Co., Ltd., trade name: CIKcap) )
(3) Wired single crystal solar cells: 125 mm long and 250 mm long and 0.2 mm thick (manufactured by Asden Co., Ltd.)
(4) Sealing member: ethylene / vinyl acetate copolymer sheet having a length of 150 mm in length and width and a thickness of 0.45 mm (trade name: CIKcap, manufactured by CI Kasei Co., Ltd.)
(5) Back surface protection member: sheet having a length and width of 150 mm each and a thickness of 0.3 mm (M packaging, trade name: PTD250)

Example 1
BR-80 (Mitsubishi Rayon Co., Ltd., trade name, Mw: 108,000, refractive index: 1.492) 100 parts as (meth) acrylic resin (A), RCF-600 (Nippon Sheet Glass as glass (B) Product name, particle size: 437 μm, aspect ratio: 87, refractive index: 1.52) 11 parts and benzoic acid ester (C), Polycizer W-83 (manufactured by DIC Corporation, product name) 1 Put 1 part in a polyethylene bag, shake the polyethylene bag well by hand and dry blend the one added to the polyethylene bag, then single screw extruder (manufactured by Thermo Plastics Co., Ltd.) The product was melt-kneaded at 250 ° C. using a 30 mmφ single-screw extruder), and the extruded strand was cut into pellets to obtain pellets.

  The above pellets are molded by an injection molding machine (trade name: IS100EN, manufactured by Toshiba Machine Plastic Engineering Co., Ltd.) at a molding temperature of 250 ° C and a mold temperature of 80 ° C. A dumbbell No. 1 type tensile test piece was obtained. The evaluation results are shown in Table 1.

(Examples 2 and 3)
Except having changed the compounding quantity of benzoic acid ester (C) into the quantity shown in Table 1, it carried out similarly to Example 1, and obtained the molded object and the dumbbell No. 1 type | mold tensile test piece. The evaluation results are shown in Table 1.
Abbreviations in Table 1 indicate the following compounds.
BR-80: Methacrylic resin (trade name, manufactured by Mitsubishi Rayon Co., Ltd.)
RCF-600: Glass flake (trade name, manufactured by Nippon Sheet Glass Co., Ltd.)
W-83: (manufactured by DIC Corporation, trade name: Polycizer W-83)
H1P: Polycaprolactone (manufactured by Daicel Corporation, trade name: Plaxel H1P)

(Comparative Example 1)
The molded product and dumbbell No. 1 type were used in the same manner as in Example 1 except that the benzoic acid ester (C) was not used and the compositions of the (meth) acrylic resin (A) and the glass (B) were changed to the compositions shown in Table 1. A tensile specimen was obtained. The evaluation results are shown in Table 1. Since no benzoic acid ester is used, the haze of the molded product is high. Moreover, the power generation efficiency of the solar cell module is low.

(Comparative Example 2)
A molded product and a molded product were obtained in the same manner as in Example 1, except that polycaprolactone (manufactured by Daicel Corporation, trade name: Plaxel H1P) was used instead of the benzoate ester (C), and the composition was changed to the composition shown in Table 1. A dumbbell No. 1 type tensile test piece was obtained. The evaluation results are shown in Table 1. Since the benzoic acid ester (C) is not used, the haze of the molded body is high and the tensile elastic modulus is low. Moreover, the power generation efficiency of the solar cell module is low.

(Comparative Example 3)
A molded product and a molded product were obtained in the same manner as in Example 1, except that polycaprolactone (manufactured by Daicel Corporation, trade name: Plaxel H1P) was used instead of the benzoate ester (C), and the composition was changed to the composition shown in Table 1. A dumbbell No. 1 type tensile test piece was obtained. The evaluation results are shown in Table 1. Since the benzoic acid ester (C) is not used, the molded article has a low tensile elastic modulus. Moreover, the power generation efficiency of the solar cell module is low.

(Comparative Example 4)
A molded product and a molded product were obtained in the same manner as in Example 1, except that polycaprolactone (manufactured by Daicel Corporation, trade name: Plaxel H1P) was used instead of the benzoate ester (C), and the composition was changed to the composition shown in Table 1. A dumbbell No. 1 type tensile test piece was obtained. The evaluation results are shown in Table 1. Since the benzoic acid ester (C) is not used, the molded article has a low tensile elastic modulus. Moreover, the power generation efficiency of the solar cell module is low.

1: Solar cell module 2: Solar cell top sheet 3: Sealing material 4: Solar cell 5: Back sheet

Claims (8)

  (Meth) acrylic resin composition containing (meth) acrylic resin (A) 100 parts by mass, glass (B) 5-40 parts by mass and benzoic acid ester (C) 0.1-20 parts by mass.   The (meth) acrylic resin composition according to claim 1, wherein the glass (B) is scaly glass.   The (meth) acrylic resin composition according to claim 2, wherein the glass flakes have a particle diameter of 100 to 2,000 µm and an aspect ratio of 15 or more.   The (meth) acrylic resin composition according to any one of claims 1 to 3, wherein the absolute value of the difference between the refractive index of the (meth) acrylic resin (A) and the refractive index of the glass (B) is 0.08 or less.   The molded object obtained by shape | molding the (meth) acrylic resin composition in any one of Claims 1-4.   An optical member using the molded article according to claim 5.   A solar cell top sheet using the optical member according to claim 6.   A solar cell module using the solar cell top sheet according to claim 7.