WO2012043243A1

WO2012043243A1 - Laminated sheet and solar cell module equipped with same

Info

Publication number: WO2012043243A1
Application number: PCT/JP2011/071031
Authority: WO
Inventors: 篤史渡邉; 由起子関口
Original assignee: テクノポリマー株式会社
Priority date: 2010-09-29
Filing date: 2011-09-14
Publication date: 2012-04-05

Abstract

A laminated sheet (1) is provided with an A layer (11) that contains an infrared permeable colorant and an ethylene-vinyl acetate resin having a vinyl acetate unit content of 2-25% by mass, a B layer (12) that contains an ethylene-vinyl acetate resin and a white colorant, and a C layer (13) that contains a saturated polyester resin, in that order. Further, a D layer (14) that acts as a water vapor barrier can be provided in as an intermediate layer, in at least one of the following positions: between the A layer (11) and the B layer (12), between the B layer (12) and the C layer (13), or between a plurality of C layers (13).

Description

Laminated sheet and solar cell module including the same

The present invention absorbs visible light in the received outermost layer when light is radiated on a specific surface of the surface, but transmits infrared light and is less likely to store heat, and transmits light through the outermost layer in the inner layer. The laminated sheet has the property of reflecting the heat and has a resin layer with excellent heat resistance and excellent adhesion to members containing ethylene / vinyl acetate resin, etc. The present invention relates to a laminated sheet having excellent durability as a compound and a solar cell module including the same.
Further, according to another aspect of the present invention, when light is emitted to a specific surface on one side, visible light is absorbed by the outermost surface layer that is received, but infrared rays are transmitted and hardly store heat, and the innermost layer is the outermost layer. The laminated sheet has the property of reflecting the light that has passed through and has excellent water vapor barrier properties from one side to the other side. Excellent heat resistance and adhesion to members containing ethylene / vinyl acetate resin, etc. The present invention relates to a laminated sheet that has an excellent resin layer, is less likely to tear due to a cold cycle environment in this bonded state, and has excellent durability as an integrated product, and a solar cell module including the same.
The laminated sheet of the present invention is generally suitable as a sheet known as a solar cell backsheet or the like, and a filler containing an ethylene / vinyl acetate resin or the like that embeds the solar cell element on the surface of the layer (A). It is used for adhering to the exposed surface of the part (the surface of the back side sealing film).

In recent years, solar cells have received more attention as energy supply means in place of petroleum, which is an energy source that forms carbon dioxide, which causes global warming. The demand for solar cells is also increasing, and there is a demand for stable supply and cost reduction of various members constituting solar cell modules included in solar cells. In addition, there is an increasing demand for improving the power generation efficiency of solar cells.
In the solar cell module, a large number of plate-like solar cell elements are arranged, and these are wired in series and in parallel, and packaged to protect the elements and unitized. In this solar cell module, the surface of the solar cell element that is exposed to sunlight is usually covered with a glass plate. For example, a composition containing ethylene / vinyl acetate resin or the like is highly transparent and excellent in moisture resistance. A stopper is filled in the gap between the solar cell elements to form a filler portion, and the exposed surface of the filler portion is bonded and sealed with a solar cell backsheet or the like.

When arranging solar cells on the roof of a house, etc., it is preferred to be colored in a dark color such as black from the viewpoint of appearance, and for that reason, it is colored in a dark color A sheet is sought. As a sheet colored in a dark color, a sheet made of carbon black is generally used. However, in this embodiment, the carbon black absorbs sunlight and the temperature rises, so that not only the power generation efficiency of the solar cell is lowered, but also the durability of the sheet may be lowered.

In order to avoid an increase in temperature due to absorption of sunlight, a sheet made of a low heat storage thermoplastic resin composition containing a thermoplastic resin and an inorganic pigment having infrared reflection characteristics is known (see Patent Document 1). Also known is a sheet that has a black resin layer containing a perylene pigment on the surface and prevents near heat storage by reflecting near infrared rays with a reflectance of light of wavelength 800-1100 nm being 30% or more. (See Patent Document 2). Furthermore, a colored resin layer having a low absorption rate of infrared rays (wavelength 800 to 1,400 nm) is provided on one side of the thermoplastic resin layer having excellent heat resistance, and light is applied to the other side of the thermoplastic resin layer. An infrared reflective laminate including at least three layers having a colored resin layer having a high reflectance (wavelength of 400 to 1,400 nm) of 50% or more is known (see Patent Document 3).

In addition, in a solar cell module including a solar cell backsheet, when water, water vapor, or the like enters from the solar cell backsheet side, the solar cell element may be deteriorated and the power generation efficiency may be lowered.

JP 2007-103813 A JP 2007-128943 A JP 2009-177851 A

The present invention absorbs visible light in the received outermost layer when light is radiated on a specific surface of the surface, but transmits infrared light and is less likely to store heat, and light transmitted through the outermost layer in the inner layer. It is a laminated sheet that has the property of reflecting light and has a resin layer with excellent heat resistance and excellent adhesion to members containing ethylene / vinyl acetate resin, etc., and tearing due to the cold cycle environment occurs in this bonded state It is an object of the present invention to provide a laminated sheet that is difficult to be integrated and has excellent durability and a solar cell module including the same.

Further, according to the present invention, when light is radiated to a specific surface on one side, visible light is absorbed by the outermost surface layer received, but infrared rays are transmitted and hardly store heat, and the innermost layer transmits the outermost layer. The laminated sheet has the property of reflecting light, and has a resin layer with excellent heat resistance and excellent adhesion to a member containing ethylene / vinyl acetate resin, etc. An object of the present invention is to provide a laminated sheet that is less likely to occur and has an excellent water vapor barrier property from one surface side to the other surface side, and a solar cell module including the laminated sheet.

The present invention is shown below.
1. A layer (A) containing an ethylene / vinyl acetate resin having a vinyl acetate unit content of 2 to 25% by mass and an infrared transmitting colorant;
A layer (B) containing an ethylene-vinyl acetate resin and a white colorant;
A layer (C) containing a saturated polyester resin;
Are sequentially provided.
2. 2. The laminated sheet according to 1 above, wherein the content of vinyl acetate units constituting the ethylene / vinyl acetate resin in the layer (A) is more than 8% by mass and 25% by mass or less.
3. 3. The laminated sheet according to 1 or 2 above, wherein the layer (C) comprises at least one layer selected from a white layer containing a white colorant, a transparent layer, and a translucent layer.
4). Furthermore, the lamination sheet as described in any one of said 1 thru | or 3 provided with a water vapor | steam barrier layer (D) as an intermediate | middle layer.
5. The laminated sheet according to 4, wherein the water vapor barrier layer (D) is provided between the layer (B) and the layer (C).
6). The laminated sheet according to 4, wherein the water vapor barrier layer (D) is provided between the plurality of layers (C).
7. The laminated sheet according to any one of 4 to 6 above, wherein the water vapor barrier layer (D) is a vapor-deposited film in which a film containing a metal and / or a metal oxide is formed on the surface of a resin layer.
8). 8. The laminated sheet according to any one of 1 to 7 above, wherein when light having a wavelength of 400 to 700 nm is radiated to the surface of the layer (A) in the laminated sheet, the light absorptance is 60% or more.
9. The laminate according to any one of 1 to 8 above, wherein when light having a wavelength of 800 to 1,400 nm is radiated to the surface of the layer (A) in the laminate sheet, the reflectance with respect to the light is 50% or more. Sheet.
10. 10. The laminated sheet according to any one of 1 to 9 above, which has a thickness of 30 to 900 μm.
11. A solar cell module comprising the laminated sheet according to any one of 1 to 10 above.

In the present invention, the laminated sheet comprising the layer (A), the layer (B) and the layer (C) (hereinafter referred to as “laminated sheet of the first aspect”) has a dark color appearance, and the layer (A) When light is radiated on the surface, it absorbs visible light in the layer (A), which is the light-receiving layer, but transmits infrared light and is difficult to store heat, and reflects light that has passed through the layer (A) in the layer (B). It is the laminated sheet which has the property to do. According to the laminated sheet of the first aspect of the present invention, excellent heat resistance, excellent adhesion between the surface of the layer (A) and a member containing ethylene / vinyl acetate resin, etc. It is difficult to generate and has excellent durability as an integrated product. In other words, the laminated sheet of the first aspect of the present invention is also excellent in the adhesion durability of an integrated product formed by adhering a member containing ethylene / vinyl acetate resin or the like.
The laminated sheet according to the first aspect of the present invention is used as a back sheet for a solar cell, and includes a surface of the layer (A), an ethylene / vinyl acetate resin, and the like, and a filler that embeds the solar cell element. The solar cell module by adhering the exposed portion to the solar cell module, the sunlight leaked from the gap between adjacent solar cell elements toward the solar cell backsheet (laminated sheet). In some cases, light such as infrared rays transmitted through the layer (A) can be reflected at the layer (B), and the reflected light can be emitted to the solar cell element and used for photoelectric conversion, thereby improving the photoelectric conversion efficiency. it can. The layer (C) can be composed of at least one layer selected from a white layer containing a white colorant, a transparent layer, and a semi-transparent layer. The layer (C) is a white layer. In some cases, the photoelectric conversion efficiency can be further improved by utilizing a high reflectance.

In the present invention, the laminated sheet comprising the layer (A), the layer (B), the layer (C) and the water vapor barrier layer (D) (hereinafter referred to as “laminated sheet of the second embodiment”) has a dark color appearance. When a light beam is emitted to the surface of the layer (A), the layer (A) that is the light receiving layer absorbs visible light, but the infrared ray is transmitted and hardly stores heat. In the layer (B), the layer (A The laminated sheet has the property of reflecting the light transmitted through) and has an excellent water vapor barrier property from one surface side to the other surface side. According to the laminated sheet of the second aspect of the present invention, excellent heat resistance, excellent adhesion between the surface of the layer (A) and a member containing ethylene / vinyl acetate resin, etc. It is hard to generate | occur | produce and it is excellent in the water vapor | steam barrier property from the surface on the opposite side of a layer (A). That is, the durability of an integrated product obtained by bonding the laminated sheet of the second aspect of the present invention to a member containing ethylene / vinyl acetate resin or the like on the surface of the layer (A) is excellent.
The laminated sheet according to the second aspect of the present invention is used as a back sheet for a solar cell, and includes a surface of the layer (A), an ethylene / vinyl acetate resin and the like, and a filler that embeds the solar cell element. The solar cell module by adhering to the exposed portion of the solar cell, the sunlight leaked toward the solar cell backsheet (laminated sheet) from the gap between the adjacent solar cell elements. In some cases, light such as infrared rays transmitted through the layer (A) can be reflected at the layer (B), and the reflected light can be emitted to the solar cell element and used for photoelectric conversion, thereby improving the photoelectric conversion efficiency. it can. And when a solar cell provided with this solar cell module is arrange | positioned on roofs, such as a house and a building, and is exposed to a wind and rain, it can acquire the outstanding durability by a water vapor | steam barrier layer (D). . In addition, without depending on the position of the water vapor barrier layer (D), the layer (C) is composed of at least one layer selected from a white layer containing a white colorant, a transparent layer, and a translucent layer. However, when this layer (C) is a white layer, the photoelectric conversion efficiency can be further improved by utilizing a high reflectance.

In the laminated sheet of the present invention, when the content of vinyl acetate units constituting the ethylene / vinyl acetate resin in the layer (A) is more than 8% by mass and 25% by mass or less, the layer ( When adhering the surface of A) and a member containing ethylene / vinyl acetate resin or the like, it is possible to obtain excellent adhesion in the integrated product at a low temperature such as 110 ° C. Can be improved.
In the laminated sheet of the present invention, when light having a wavelength of 400 to 700 nm is emitted to the surface of the layer (A) in the laminated sheet, the light absorptance can be 60% or more. Therefore, when the laminated sheet of the present invention is used as a back sheet for a solar cell, a solar cell module excellent in dark color appearance according to the color of the infrared transmitting colorant blended in the layer (A) is used. When a solar cell module provided with this laminated sheet is disposed on the roof of a house or the like, excellent appearance and design can be obtained.
The laminated sheet of the present invention can have a reflectance of 50% or more when light having a wavelength of 800 to 1,400 nm is emitted to the surface of the layer (A) in the laminated sheet. Therefore, when the laminated sheet of the present invention is used as a back sheet for a solar cell and a solar cell module is formed, the sunlight is leaked from the gap between adjacent solar cell elements toward the laminated sheet. Heat storage in the sheet is suppressed. And the light which reflected the light which permeate | transmitted the layer (A) by the layer (B) etc. can be entered into a solar cell element, and electric power generation efficiency can be improved.
When the thickness of the laminated sheet of the present invention is 30 to 900 μm, it is excellent in strength and flexibility.

Since the solar cell module of the present invention includes the laminated sheet of the present invention, it is suitable for outdoor use exposed to sunlight or wind and rain for a long period of time, and has excellent power generation efficiency in the solar cell.

It is a schematic sectional drawing which shows an example of the lamination sheet of a 1st aspect. It is a schematic sectional drawing which shows the other example of the lamination sheet of a 1st aspect. It is a schematic sectional drawing which shows the other example of the lamination sheet of a 1st aspect. It is a schematic sectional drawing which shows the other example of the lamination sheet of a 1st aspect. It is a schematic sectional drawing which shows the other example of the lamination sheet of a 1st aspect. It is a schematic sectional drawing which shows an example of the lamination sheet of a 2nd aspect. It is a schematic sectional drawing which shows the other example of the lamination sheet of a 2nd aspect. It is a schematic sectional drawing which shows the other example of the lamination sheet of a 2nd aspect. It is a schematic sectional drawing which shows the other example of the lamination sheet of a 2nd aspect. It is a schematic sectional drawing which shows the other example of the lamination sheet of a 2nd aspect. It is a schematic sectional drawing which shows the other example of the lamination sheet of a 2nd aspect. It is a schematic sectional drawing which shows the other example of the lamination sheet of a 2nd aspect. It is a schematic sectional drawing which shows the other example of the lamination sheet of a 2nd aspect. It is a schematic sectional drawing which shows an example of a solar cell module. In an Example, it is a schematic plan view which shows the form of the lamination sheet used for a thermal cycle test. In an Example, it is a schematic sectional drawing which shows the sample structure used for a thermal cycle test.

The present invention will be described in detail below.
In this specification, “(meth) acryl” means acrylic and methacrylic. “Ethylene / vinyl acetate resin” is a copolymer composed of an ethylene unit and a vinyl acetate unit, a copolymer composed of an ethylene unit, a vinyl acetate unit, and another monomer unit. A saponified product of the above copolymer. The “vinyl acetate unit content” means a ratio when the total amount of all units constituting the ethylene / vinyl acetate resin is 100% by mass.

The laminated sheet of the first aspect of the present invention comprises a layer (A) containing an ethylene / vinyl acetate resin and an infrared transmitting colorant having a vinyl acetate unit content of 2 to 25% by mass, an ethylene / vinyl acetate resin and a white color. A layer (B) containing a colorant and a layer (C) containing a saturated polyester resin are sequentially provided, and a schematic cross section thereof is illustrated in FIG. That is, the laminated sheet 1 in FIG. 1 is a laminated sheet that includes a layer (A) 11, a layer (B) 12, and a layer (C) 13 in this order. In addition, it has the other layer 15 except the water vapor | steam barrier layer mentioned later on the layer (C) side surface etc. between the layer (A) and the layer (B), between the layer (B) and the layer (C). Also good.
The laminated sheet according to the first aspect of the present invention may further have a schematic cross section shown in FIGS. That is, the laminated sheet 1 of FIG. 2 sequentially includes a layer (A) 11, a layer (B) 12, and a layer (C) 13 including a layer 131 containing a saturated polyester resin and a layer 132 containing a saturated polyester resin. It is a laminated sheet provided. 3 includes a layer (A) 11, a layer (B) 12, a layer 131 containing a saturated polyester resin, a layer 132 containing a saturated polyester resin, and a layer 133 containing a saturated polyester resin. (C) 13 is a laminated sheet having 13 in order. The saturated polyester resin contained in the layer 131, the saturated polyester resin contained in the layer 132, and the saturated polyester resin contained in the layer 133 may be the same as or different from each other. Moreover, it can also be set as the layer (C) which consists of four or more layers.
In these embodiments, for example, as a raw material for forming the layer (C) during the production of the laminated sheet, the raw material for forming the layer 131, the raw material for forming the layer 132, and the like are both two kinds of raw materials containing saturated polyester resin. This is an example in which a continuous layer is formed using these raw materials. In the case of FIG. 2, it is a layer (C) in which two layers containing a saturated polyester resin are continuous, and in the case of FIG. 3, it is a layer (C) in which three layers containing a saturated polyester resin are continuous. 2 and FIG. 3 is an example of the multilayer type related to the layer (C), and is not limited to the layer (C). Although not shown, the layer (A) and the layer (B) ) Is the same.
Moreover, FIG.4 and FIG.5 is an example of the lamination sheet of a 1st aspect provided with the other layer 15 except the water vapor | steam barrier layer mentioned later. FIG. 4 is a laminated sheet that includes a layer (A) 11, a layer (B) 12, another layer 15 and a layer (C) 13 in order, and FIG. 5 illustrates a layer (A) 11 and a layer (B). ) 12, a layer (C) 13 and another layer 15 are sequentially provided.

The laminated sheet of the second aspect of the present invention comprises a layer (A) containing an ethylene / vinyl acetate resin and an infrared transmitting colorant having a vinyl acetate unit content of 2 to 25% by mass, an ethylene / vinyl acetate resin and a white color. A layer (B) containing a colorant, a layer (C) containing a saturated polyester resin, and a water vapor barrier layer (D).
The layer (A) is the outermost layer on one side of the laminated sheet.
The layer (B) is a layer located at least between the layer (A) and the layer (C).
The layer (C) may be two or more independent layers in the laminated sheet, and the intermediate layer located on the opposite side of the layer (A) to the layer (B) or the outermost layer on the other surface side. It is a surface layer.
The water vapor barrier layer (D) may also be two or more independent layers, and is an intermediate layer in the laminated sheet. In this case, the “intermediate layer” means a layer positioned between the layer (A) which is the outermost layer on one side and the outermost layer on the other side.
The laminated sheet of the second aspect in the present invention can further include another layer 15 described later. The other layer is an intermediate layer or the outermost layer on the other surface side of the laminated sheet.

As described above, each of the layer (C) and the water vapor barrier layer (D) may be two or more independent layers. For example, the layer (C) will be described. ) May be included through a water vapor barrier layer (D) or other layers. Therefore, the water vapor barrier layer (D) is formed between the layer (A) and the layer (B), between the layer (A) and another layer, inside the layer (B), that is, a plurality of layers (B Between layers, between layer (B) and other layers, within layer (C), ie between layers (C), between layer (C) and other layers, etc. Can be located.

The schematic cross section of the laminated sheet of the second aspect in the present invention is exemplified in FIG. 6. The laminated sheet 1 in FIG. 6 includes a layer (A) 11, a water vapor barrier layer (D) 14, a layer (B) 12 and a layer. (C) 13 is a laminated sheet having 13 in order.
The laminated sheet according to the second aspect of the present invention may further have a schematic cross section shown in FIG. 7, FIG. 8, FIG. 9, FIG. 10, FIG. That is, the laminated sheet 1 in FIG. 7 is a laminated sheet that includes a layer (A) 11, a layer (B) 12, a water vapor barrier layer (D) 14, and a layer (C) 13 in this order. The laminated sheet 1 in FIG. 8 includes a layer (A) 11, a layer (B) 12, a water vapor barrier layer (D) 14, a layer (C) 13a containing a saturated polyester resin, and a layer (C) 13a containing a saturated polyester resin. These are laminated sheets that are sequentially provided. 9 includes a layer (A) 11, a layer (B) 12, a layer (C) 13a containing a saturated polyester resin, a water vapor barrier layer (D) 14 and a layer (C) 13b containing a saturated polyester resin. These are laminated sheets that are sequentially provided. The laminated sheet 1 in FIG. 10 is a laminated sheet comprising a layer (A) 11, a water vapor barrier layer (D) 14a, a layer (B) 12, a water vapor barrier layer (D) 14b, and a layer (C) 13 in this order. is there. The laminated sheet 1 of FIG. 11 is a laminated sheet comprising a layer (A) 11, a layer (B) 12, a water vapor barrier layer (D) 14, a layer (C) 13 and another layer 15 in this order. The laminated sheet 1 of FIG. 12 is a laminated sheet comprising a layer (A) 11, a layer (B) 12, a water vapor barrier layer (D) 14, another layer 15 and a layer (C) 13 in this order. Moreover, the laminated sheet 1 of FIG. 13 is a laminated sheet comprising a layer (A) 11, a layer (B) 12, a layer (C) 13, a water vapor barrier layer (D) 14 and another layer 15 in this order. .
As described above, the layer (C) may be two or more independent layers, and FIG. 9 shows an example thereof. The constituent material of the layer (C) 13a and the constituent material of the layer (C) 13b may be the same or different. For example, the saturated polyester resin contained in the layer (C) 13a and the saturated polyester resin contained in the layer (C) 13b may be the same or different.
The water vapor barrier layer (D) may also be two or more independent layers (not shown) as described above. In this case, the constituent materials of the plurality of water vapor barrier layers (D) may be the same as or different from each other.
A layer (B) 12 in FIGS. 6 to 13 includes a plurality of raw materials containing ethylene / vinyl acetate resin and an infrared transmitting colorant, and a continuous layer containing ethylene / vinyl acetate resin and an infrared transmitting colorant. And may be a layer (B) as a whole (not shown). The aspect of the continuous multilayer type related to the layer (B) is an example, and is not limited to the layer (B), and is not illustrated, but the same applies to the layer (A).
6 to 13, each of the layer (C) 13 or the layer (C) 13a or the layer (C) 13b includes a plurality of raw materials containing a saturated polyester resin, and a continuous layer containing a saturated polyester resin. It may be formed as a whole and may be a layer (C) as a whole (not shown).
When the laminated sheet of the second aspect in the present invention has the other layer 15, the position is preferably between the layer (A) and the water vapor barrier layer (D), the layer (B) and the water vapor barrier layer (D). Between layer (A) and layer (B), between layer (B) and layer (C), between layer (C) and water vapor barrier layer (D), on the opposite side of layer (A), etc. is there.

First, the layer (A), the layer (B), and the layer (C) in the laminated sheets of the first aspect and the second aspect will be described.
The layer (A) comprises an ethylene / vinyl acetate resin (hereinafter referred to as “ethylene / vinyl acetate resin (A)”) having a vinyl acetate unit content of 2 to 25% by mass, an infrared transmitting colorant, It is an infrared transparent colored resin layer comprising a resin composition containing, and is usually colored in a color according to the color of the infrared transparent colorant, and has a function of absorbing visible light and transmitting infrared light. is there. In addition, when the said infrared rays transparent colorant and the other colorant mentioned later are included as a coloring agent, the layer (A) is colored in the dark color which mixed these coloring agents.

In the present invention, a member comprising the surface of the layer (A), an olefin resin such as ethylene / vinyl acetate resin, a resin such as epoxy resin or polyvinyl butyral resin, a rubber such as silicone rubber or hydrogenated conjugated diene rubber, etc. (Hereinafter also referred to as “partner material”), the resulting integrated product is excellent in adhesiveness. And when layer (A) has a notch part, a notch part, etc., even if an integrated object is exposed to a thermal cycle environment, it is hard to generate defective phenomena, such as a tear, its appearance is maintained, and durability is maintained. Excellent. Further, when light is radiated from the counterpart material side, infrared rays are transmitted through the layer (A) and reflected by the layer (B) to the counterpart material side, so that heat storage of the integrated product can be suppressed. Therefore, the laminated sheet of the present invention is used as a back sheet for solar cells, and includes a surface of the layer (A), the above-described resin, rubber, etc. When the solar cell module is formed by adhering to the exposed surface, the adhesiveness, low heat storage property and durability are excellent.

As described above, the content of the vinyl acetate unit constituting the ethylene / vinyl acetate resin (A) is 2 to 25% by mass, which makes the laminated sheet of the present invention excellent in heat resistance and layer (A ) And a member (partner material) containing ethylene / vinyl acetate resin and the like, and in this bonded state, it is hard to tear due to a cold cycle environment and has excellent durability. The lower limit of the content of the vinyl acetate unit is preferably 3% by mass, more preferably 5% by mass, still more preferably more than 8% by mass, and particularly preferably 9% by mass. Moreover, the upper limit of the content rate of a vinyl acetate unit becomes like this. Preferably it is 23 mass%, More preferably, it is 22 mass%, Most preferably, it is 21 mass%. When the content of vinyl acetate units in the ethylene / vinyl acetate resin (A) exceeds 8% by mass, the layer (A) has excellent flexibility and adhesion to the mating material. Can do. In addition, when the content rate of a vinyl acetate unit exceeds 25 mass%, heat resistance is not enough.

The ethylene / vinyl acetate resin (A) contained in the layer (A) may have a crosslinked structure obtained by a method described later.

Next, the infrared transmissive colorant contained in the layer (A) is a colorant having a property of absorbing visible light and transmitting infrared light. This infrared transmissive colorant usually has a color other than white, and is preferably a dark color system such as black, brown, dark blue, or dark green.

Examples of the infrared transmitting colorant include perylene compounds, azo compounds, and azomethine azo compounds. As the perylene compound, compounds represented by the following general formulas (I) to (III) can be used.

[Wherein, R ² and R ³ are the same or different from each other, and are a butyl group, a phenylethyl group, a methoxyethyl group, or a 4-methoxyphenylmethyl group. ]

[In the formula, R ⁴ and R ⁵ are the same or different from each other, and include a phenylene group, a 3-methoxyphenylene group, a 4-methoxyphenylene group, a 4-ethoxyphenylene group, an alkylphenylene group having 1 to 3 carbon atoms, and a hydroxyphenylene group. Group, 4,6-dimethylphenylene group, 3,5-dimethylphenylene group, 3-chlorophenylene group, 4-chlorophenylene group, 5-chlorophenylene group, 3-bromophenylene group, 4-bromophenylene group, 5- Bromophenylene group, 3-fluorophenylene group, 4-fluorophenylene group, 5-fluorophenylene group, naphthylene group, naphthalenediyl group, pyridylene group, 2,3-pyridinediyl group, 3,4-pyridinediyl group, 4- Methyl-2,3-pyridinediyl group, 5-methyl-2,3-pyridinediyl group, 6-methyl Le-2,3-pyridinediyl group, 5-methyl-3,4-pyridinediyl group, 4-methoxy-2,3-pyridinediyl group, or a 4-chloro-2,3-pyridinediyl group. ]

[In the formula, R ⁶ and R ⁷ are the same or different from each other, and include a phenylene group, a 3-methoxyphenylene group, a 4-methoxyphenylene group, a 4-ethoxyphenylene group, an alkylphenylene group having 1 to 3 carbon atoms, and a hydroxyphenylene group. Group, 4,6-dimethylphenylene group, 3,5-dimethylphenylene group, 3-chlorophenylene group, 4-chlorophenylene group, 5-chlorophenylene group, 3-bromophenylene group, 4-bromophenylene group, 5- Bromophenylene group, 3-fluorophenylene group, 4-fluorophenylene group, 5-fluorophenylene group, naphthylene group, naphthalenediyl group, pyridylene group, 2,3-pyridinediyl group, 3,4-pyridinediyl group, 4- Methyl-2,3-pyridinediyl group, 5-methyl-2,3-pyridinediyl group, 6-methyl Le-2,3-pyridinediyl group, 5-methyl-3,4-pyridinediyl group, 4-methoxy-2,3-pyridinediyl group, or a 4-chloro-2,3-pyridinediyl group. ]

In addition, as the perylene-based compounds, commercially available products such as “Paligen Black S 0084”, “Palogen Black L 0086”, “Lumogen Black FK4280”, “Lumogen Black FK4281” (all of which are trade names manufactured by BASF) are used. Can be used.
The infrared transmissive colorant can be used alone or in combination of two or more.

The content of the infrared transmitting colorant in the layer (A) is 100 parts by mass of the total of the thermoplastic resin containing the ethylene / vinyl acetate resin (A) from the viewpoints of infrared transmission and visible light absorption. In this case, the amount is preferably 10 parts by mass or less, more preferably 0.01 to 8 parts by mass, still more preferably 0.05 to 5 parts by mass.
As described above, the layer (A) may have a multilayer structure including a plurality of layers containing the ethylene / vinyl acetate resin (A) and the infrared transmitting colorant. In this case, the content of the infrared transmitting colorant with respect to the total amount of the thermoplastic resin including the ethylene / vinyl acetate resin (A) in each layer can be within the above range, and from one side to the other side, It may have a concentration distribution of an infrared transmitting colorant or may be constant. Even when the layer (A) has a multilayer structure and includes other colorants, additives and the like described later, their content (thermoplasticity including ethylene / vinyl acetate resin (A) in each layer) The ratio with respect to the total amount of the resin can be within the range described below.

In the present invention, the layer (A) can contain other colorants depending on the purpose, application, etc., unless the infrared transparency of the layer (A) is reduced.
Examples of other colorants include cyan colorants (blue colorants), magenta colorants (red colorants), yellow colorants (yellow colorants), and the like.

For example, as other colorants, yellow pigments, blue pigments, and the like are used, and a laminated sheet having variously colored layers (A) can be obtained by the following combinations.
[1] Brown coloration by a combination of a black-based infrared transmitting colorant and a yellow pigment [2] Dark blue coloration by a combination of a black-based infrared transmitting colorant and a blue pigment When other colorants are used, the above layer ( The content in A) is usually 80 parts by mass or less, preferably 0.01 to 60 parts by mass with respect to 100 parts by mass of the infrared transmitting colorant.

As a dark colorant, carbon black that absorbs light having a wavelength in the infrared region is known. On the surface of the layer (A ′) of the laminated sheet comprising a layer (A ′) formed of a thermoplastic resin composition using carbon black instead of the layer (A) containing an infrared transmitting colorant, sunlight is applied. Is received, heat storage in this layer (A ′) becomes remarkable. Therefore, the laminated sheet including this layer (A ′) is used as a solar cell back sheet, and the surface of the layer (A ′) and the filler portion (exposed surface) that embeds the solar cell element are adhered. When the solar cell module is used, when sunlight leaks into the carbon black-containing layer (A ′), the temperature of the filler material portion including the solar cell element is increased from the stored solar cell backsheet. There is a problem that reduces power generation efficiency. Therefore, in the present invention, by setting the layer (A) to include an infrared transmitting colorant, it is possible to maintain low heat storage and suppress the above-described problems in solar cell applications and the like.

The layer (A) may contain an additive depending on the purpose and application. Therefore, the composition containing the ethylene / vinyl acetate resin and the infrared transmitting colorant (hereinafter referred to as “layer (A) forming resin composition”) that forms this layer (A) also contains an additive. You may contain. This additive includes antioxidants, ultraviolet absorbers, anti-aging agents, plasticizers, fluorescent brighteners, weathering agents, fillers, antistatic agents, flame retardants, antifogging agents, antibacterial agents, antifungal agents, Antifouling agents, tackifiers and the like can be mentioned. Among these additives, specific compounds in the main additives and the content in the resin composition for forming the layer (A) will be described later.

In order for the ethylene / vinyl acetate resin (A) constituting the layer (A) to have a crosslinked structure, the layer (A) forming resin composition comprises an organic peroxide, a photosensitizer, It preferably contains a silane coupling agent or the like.

The organic peroxide is not particularly limited as long as it generates radicals at a temperature of 100 ° C. or higher.
Examples of the organic peroxide include 2,5-dimethylhexane-2,5-dihydroperoxide, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane-3, di-tert- Butyl peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane, α, α'-bis (tert-butylperoxyisopropyl) benzene, n-butyl-4 , 4-Bis (tert-butylperoxy) butane, 2,2-bis (tert-butylperoxy) butane, 1,1-bis (tert-butylperoxy) cyclohexane, 1,1-bis (tert-butyl) Peroxy) 3,3,5-trimethylcyclohexane, tert-butyl peroxybenzoate, benzoyl peroxide, etc. And the like. These compounds may be used alone or in combination of two or more.
The organic peroxide is preferably a compound having a decomposition temperature of 70 ° C. or higher at a half-life of 10 hours from the viewpoint of stability at the time of blending when preparing the resin composition for forming the layer (A).
When the said layer (A) formation resin composition contains an organic peroxide, the content rate is preferably 5 mass% or less with respect to the whole thermoplastic resin containing ethylene-vinyl acetate resin.

Examples of the photosensitizer include benzoin, benzoin methyl ether, benzoin isoethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, dibenzoyl, hexachlorocyclopentadiene, paranitrodiphenyl, paranitroaniline, 2,4,6-trinitro. Examples include aniline and 1,2-benzanthraquinone. These compounds may be used alone or in combination of two or more.
When the resin composition for forming the layer (A) contains a photosensitizer, the content is preferably 10% by mass or less with respect to the entire thermoplastic resin including the ethylene / vinyl acetate resin.

In the case of using the photosensitizer, for example, a thin-walled body or the like is prepared using the resin composition for forming the layer (A), and then irradiated with light to thereby form an ethylene / vinyl acetate resin (A ) Containing layer (A) can be formed.

Examples of the silane coupling agent include γ-chloropropyltrimethoxysilane, vinyltrichlorosilane, vinyltriethoxysilane, vinyl-tris (β-methoxyethoxy) silane, γ-methacryloxypropyltrimethoxysilane, β- (3, 4-Ethoxycyclohexyl) ethyl-trimethoxysilane, γ-glycidoxypropyltrimethoxysilane, vinyltriacetoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) ) -Γ-aminopropyltrimethoxysilane and the like. These compounds may be used alone or in combination of two or more.
When the said layer (A) formation resin composition contains a silane coupling agent, the content rate is preferably 5 mass% or less with respect to the whole thermoplastic resin containing ethylene-vinyl acetate resin.

Moreover, the said resin composition for layer (A) formation can also contain a crosslinking adjuvant. Examples of the crosslinking aid include trifunctional crosslinking aids such as triallyl isocyanurate and triallyl isocyanate.
When the resin composition for forming the layer (A) contains a crosslinking aid, the content is preferably 10% by mass or less based on the entire thermoplastic resin including the ethylene / vinyl acetate resin.

When the resin composition for forming the layer (A) contains a crosslinking aid, it may further contain a polymerization inhibitor. Examples of the polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, p-benzoquinone, methyl hydroquinone and the like.
When the resin composition for forming the layer (A) contains a polymerization inhibitor, the content is preferably 5% by mass or less based on the entire thermoplastic resin including the ethylene / vinyl acetate resin.

When preparing the resin composition for forming the layer (A), a melt-kneading method is usually used. Examples of the apparatus used for melt kneading include a single screw extruder, a twin screw extruder, a Banbury mixer, a kneader, and a continuous kneader.

The thickness of the layer (A) is preferably 10 to 400 μm from the viewpoint of mechanical strength and flexibility of the laminated sheet. The upper limit of the thickness is more preferably 300 μm, still more preferably 250 μm, and particularly preferably 200 μm. The lower limit of the thickness is more preferably 15 μm, still more preferably 20 μm, and particularly preferably 25 μm.

The layer (B) is a white layer (white resin layer) made of a resin composition containing an ethylene / vinyl acetate resin (hereinafter referred to as “ethylene / vinyl acetate resin (B)”) and a white colorant. The layer is mainly a layer having light reflectivity and an effect of maintaining a balance between mechanical strength and flexibility as a laminated sheet.
As described above, since the layer (A) has an action of transmitting infrared rays, the layer (B) can efficiently reflect light containing infrared rays. This effect is particularly effective when the layer (A) and the layer (as shown in FIG. 1, FIG. 2, FIG. 3, FIG. 4, FIG. 5, FIG. 7, FIG. 8, FIG. 9, FIG. It can be obtained efficiently when B) is bonded. And in the integrated product obtained using the laminated sheet of the present invention, heat storage in the layer (A), the layer (B) and the layer (C), or the layer (A), the layer (B) and the layer (C) And heat storage in the water vapor barrier layer (D) can be suppressed. Therefore, the laminated sheet of the present invention is used as a solar cell backsheet, embedding the surface of the layer (A) and the solar cell element (s), and the gap contains ethylene / vinyl acetate resin or the like. When the solar cell module is formed by adhering to the filler portion (exposed surface) filled with the composition, sunlight is directed toward the solar cell backsheet (laminated sheet) from the gap between adjacent solar cell elements. In the case of leakage, not only the light such as infrared rays transmitted through the layer (A) is reflected on the layer (B) and the reflected light can be used for photoelectric conversion, but also heat storage in the laminated sheet can be suppressed.

The content of the vinyl acetate unit constituting the ethylene / vinyl acetate resin (B) is preferably 2 to 25% by mass, whereby the adhesiveness of the layer (A) and the layer (B) is excellent, and the layer ( B) Excellent adhesion of layer (C), excellent adhesion of layer (B) and water vapor barrier layer (D), excellent heat resistance of the laminated sheet of the present invention, layer (A) and counterpart in laminated sheet In the bonded state of the material, it is difficult to tear due to the cold cycle environment and has excellent durability. The lower limit of the content of the vinyl acetate unit is preferably 3% by mass, more preferably 5% by mass, still more preferably more than 8% by mass, and particularly preferably 9% by mass. Moreover, the upper limit of the content rate of a vinyl acetate unit becomes like this. Preferably it is 23 mass%, More preferably, it is 22 mass%, Most preferably, it is 21 mass%. When the content of vinyl acetate units in the ethylene / vinyl acetate resin (B) exceeds 8% by mass, in particular, the adhesion between the layer (B) and the layer (A), the layer (B) and the layer (C) The adhesion between the layer (B) and the water vapor barrier layer (D) can be further improved. In addition, when the content rate of a vinyl acetate unit exceeds 25 mass%, heat resistance may not be enough.

Similarly to the ethylene / vinyl acetate resin (A), the ethylene / vinyl acetate resin (B) contained in the layer (B) may have a crosslinked structure.
The ethylene / vinyl acetate resin (B) may be the same as or different from the ethylene / vinyl acetate resin (A).

Examples of the white colorant contained in the layer (B) include titanium oxide, zinc oxide, calcium carbonate, barium sulfate, calcium sulfate, alumina, silica, 2PbCO ₃ .Pb (OH) ₂ , [ZnS + BaSO ₄ ], talc, Examples include gypsum. These may be used alone or in combination of two or more.

The content of the white colorant in the layer (B) is 100 in terms of the total of the thermoplastic resins including the ethylene / vinyl acetate resin (B), particularly from the viewpoint of reflectivity with respect to light having a wavelength of 800 to 1,400 nm. In terms of parts by mass, it is preferably 1 to 45 parts by mass, more preferably 3 to 40 parts by mass, and still more preferably 5 to 30 parts by mass. If the white colorant content is too low, the light reflectance may not be sufficient. On the other hand, if the content of the white colorant is too high, the mechanical strength, flexibility and the like of the laminated sheet may be lowered.
As described above, the layer (B) can have a multilayer structure including a plurality of layers containing the ethylene / vinyl acetate resin (B) and the white colorant. In this case, the content of the white colorant relative to the thermoplastic resin containing the ethylene / vinyl acetate resin (B) in each layer can be within the above range, and the white colorant from one side to the other side. The concentration distribution may be constant or constant. Even when the layer (B) has a multilayer structure and includes other colorants, additives and the like described later, their content (thermoplasticity including ethylene / vinyl acetate resin (B) in each layer) The ratio with respect to the total amount of the resin can be within the range described below.

The layer (B) is a white layer, and the L value (brightness) on the surface of the single layer film is preferably 60 or more, more preferably 65 or more, and particularly preferably 70 or more.

The layer (B) may contain a colorant other than the white colorant (for example, a yellow colorant, a blue colorant, etc.) as long as the L value is not lowered. When using other colorants, the content is usually 10 parts by mass or less when the total of the thermoplastic resins including the ethylene / vinyl acetate resin (B) is 100 parts by mass.

The layer (B) may contain an additive depending on the purpose and application. Therefore, the composition containing the ethylene / vinyl acetate resin and the white colorant (hereinafter referred to as “layer (B) forming resin composition”) forming the layer (B) also contains an additive. May be. This additive includes antioxidants, ultraviolet absorbers, anti-aging agents, plasticizers, fluorescent brighteners, weathering agents, fillers, antistatic agents, flame retardants, antifogging agents, antibacterial agents, antifungal agents, Antifouling agents, tackifiers and the like can be mentioned. Among these additives, specific compounds in the main additives and the content ratio in the resin composition for forming the layer (B) will be described later.

In order for the ethylene / vinyl acetate resin (B) constituting the layer (B) to have a crosslinked structure, the layer (B) is formed in the same manner as in the case of the resin composition for forming the layer (A). The forming resin composition may contain an organic peroxide, a photosensitizer, a silane coupling agent, or the like.
When the layer (B) forming resin composition contains an organic peroxide, a photosensitizer, a silane coupling agent or the like, these contents are included in the layer (B) forming resin composition. The ratio of the thermoplastic resin containing ethylene / vinyl acetate resin (A) contained in the resin composition for forming the layer (A) on the basis of the thermoplastic resin containing ethylene / vinyl acetate resin (B), It can be applied as it is.

When preparing the resin composition for forming the layer (B), a melt-kneading method is usually used. Examples of the apparatus used for melt kneading include a single screw extruder, a twin screw extruder, a Banbury mixer, a kneader, and a continuous kneader.

The thickness of the layer (B) is preferably 10 to 400 μm from the viewpoint of mechanical strength and flexibility of the laminated sheet. The upper limit of the thickness is more preferably 300 μm, still more preferably 250 μm, and particularly preferably 200 μm. The lower limit of the thickness is more preferably 15 μm, still more preferably 20 μm, and particularly preferably 25 μm.

The layer (C) is a layer containing a saturated polyester resin which is a thermoplastic resin, and may be any of a colored layer, a transparent layer and a translucent layer. And this layer (C) is a layer which mainly provides durability while improving the mechanical strength of the laminated sheet of this invention. Therefore, when the laminated sheet of the present invention is used as a solar cell backsheet and the solar cell module is formed as described above, thermal deformation due to use of the solar cell is suppressed, and heat resistance is excellent. When this layer (C) is a white layer containing a white colorant, the light transmitted through the layer (A) and the layer (B), or the layer (A), the layer (B) and the water vapor barrier layer ( The reflectance of the light transmitted through D) to the layer (A) side, that is, the solar cell element side can be improved.

The saturated polyester resin is preferably a resin obtained by polycondensation reaction of a dicarboxylic acid component and a glycol component.
Dicarboxylic acid components include terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenylsulfonedicarboxylic acid, diphenoxyethanedicarboxylic acid, 5-sodium sulfoisophthalic acid and other aromatic dicarboxylic acids Alicyclic dicarboxylic acids such as oxalic acid, succinic acid, adipic acid, sebacic acid, dimer acid, maleic acid and fumaric acid; alicyclic dicarboxylic acids such as cyclohexyne dicarboxylic acid; oxycarboxylic acids such as p-oxybenzoic acid; Etc.
Examples of the glycol component include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-butanediol, and 1,6-hexane. Aliphatic glycols such as diol and neopentyl glycol; polyoxyalkylene glycols such as diethylene glycol, polyethylene glycol, polypropylene glycol and polytetramethylene glycol; alicyclic glycols such as 1,4-cyclohexanedimethanol; bisphenol A, bisphenol S, etc. Aromatic glycols, and the like.
Each of these dicarboxylic acid components and glycol components may be used alone or in combination of two or more.

As the saturated polyester resin, a polyester resin containing ethylene terephthalate as a main constituent unit obtained by a polycondensation reaction using terephthalic acid or dimethyl terephthalate and ethylene glycol using an esterification reaction or an ester exchange reaction is preferable. By using this polyester resin, it is excellent in mechanical strength, workability, thermal characteristics and the like. The “main structural unit” means that the content of ethylene terephthalate constituting the polyester resin is 30 mol% or more. As the saturated polyester resin, polyethylene-2,6-naphthalate resin is also preferably used from the viewpoint of strength and heat stability.

The layer (C) may contain other thermoplastic resin in addition to the saturated polyester resin. Other thermoplastic resins include acrylic resins containing structural units derived from (meth) acrylic acid ester compounds, aromatic vinyl resins containing structural units derived from aromatic vinyl compounds, polyolefin resins, polyvinyl chloride resins; Examples thereof include polyvinylidene chloride resin, polyvinyl acetate resin, polycarbonate resin, fluorine resin, and ethylene / vinyl acetate resin. These can be used alone or in combination of two or more.

When the layer (C) contains another thermoplastic resin, the content thereof is preferably less than 50% by mass, more preferably 40% by mass or less, still more preferably 30% by mass with respect to the saturated polyester resin. It is as follows.

The layer (C) may be a colored layer containing a colorant, and in this case, the color of the layer (C) is appropriately selected depending on the purpose, application and the like.

As described above, in the case of the laminated sheet of the first aspect including the layer (C) that is a white layer containing a white colorant, that is, when the layer 13 in FIG. 1 is a white layer, the layer 131 in FIG. When at least one of the layers 132 is a white layer (however, when there is a remaining layer that is not a white layer, it is preferably a transparent layer or a translucent layer), and the layer 131 in FIG. In the case where at least one of 132 and 133 is a white layer (however, when there is a remaining layer that is not a white layer, it is preferably a transparent layer or a semi-transparent layer) The reflectance of the light transmitted through A) and the layer (B) toward the layer (A) can be improved.

Further, in the case of the laminated sheet of the second embodiment provided with the layer (C) that is a white layer containing a white colorant, that is, the layer 13 in FIGS. 6, 7, 10, 11, 12, and 13 is When it is a white layer, when at least one of the layer 13a and the layer 13b in FIG. 8 is a white layer (however, it contains a saturated polyester resin, but there is a remaining layer that is not a white layer, preferably 9 and a case where at least one of the

layers

13a and 13b in FIG. 9 is a white layer (however, the remaining layer which includes a saturated polyester resin but is not a white layer) In some cases, it is preferably a transparent layer or a semi-transparent layer), and enters from the layer (A) side, and then passes through the layer (A), the layer (B), and the water vapor barrier layer (D). Layer of light (A) It is possible to improve the reflectance of the.

As the white colorant used when at least one layer constituting the layer (C) is a white layer, the compounds exemplified as the white colorant contained in the layer (B) can be applied, The white colorant contained in the layer (B) may be the same or different.

The content of the white colorant in the white layer is, in particular, from the viewpoint of reflectivity with respect to light having a wavelength of 800 to 1,400 nm, when the total amount of the thermoplastic resin including the saturated polyester resin is 100 parts by mass. The amount is preferably 1 to 45 parts by mass, more preferably 3 to 40 parts by mass, and still more preferably 5 to 30 parts by mass. If the content of the white colorant is too low, the light reflectance may not be sufficient. On the other hand, if the content of the white colorant is too high, the mechanical strength, flexibility, and the like of the laminated sheet may be reduced.

When at least one layer constituting the layer (C) is a white layer, this white layer is a colorant other than the white colorant (for example, a yellow colorant) as long as it does not reduce the following L value. Colorants, blue colorants, etc.). When other colorants are used, the content is usually 10 parts by mass or less when the total of the thermoplastic resins including the saturated polyester resin is 100 parts by mass.

Regarding the L value (lightness) of the white layer, the L value on the surface of the film composed of the single layer is preferably 60 or more, more preferably 65 or more, and particularly preferably 70 or more.
In addition, when the said layer (C) is a laminated structure which consists of a white layer and a transparent layer or a semi-transparent layer, L value of the surface by the side of a transparent layer or a semi-transparent layer becomes like this. Preferably it is 60 or more, More preferably Is 65 or more, particularly preferably 70 or more.

When the laminated sheet according to the first aspect of the present invention has the structure shown in FIG. 2 and at least one layer constituting the layer (C) is a white layer, it is reflective to light having a wavelength of 800 to 1,400 nm. In view of the above, preferred embodiments are as follows.
(C1-1) The laminated sheet (C1-2) layer 131 in which the layer 131 is a white layer and the layer 132 is a transparent layer, a semi-transparent layer or a colored layer (may be a white layer) is a transparent layer or a semi-layer Laminated sheet which is a transparent layer and the layer 132 is a white layer

In addition, when the laminated sheet of the first aspect of the present invention has the structure shown in FIG. 3 and at least one layer constituting the layer (C) is a white layer, it is suitable for light with a wavelength of 800 to 1,400 nm. From the viewpoint of reflectivity, preferred embodiments are as follows.
(C2-1) Laminated sheet (C2-2) layer 131 in which layer 131 is a white layer, layer 132 is a transparent layer or a translucent layer, and layer 133 is a colored layer (may be a white layer). Is a white layer, the layer 132 is a white layer, the layer 133 is a transparent layer, a semi-transparent layer or a colored layer (may be a white layer). The laminated sheet (C2-3) layer 131 is a transparent layer or Laminated sheet (C2-4) layer 131 which is a translucent layer, layer 132 is a transparent layer or a translucent layer, layer 133 is a white layer, layer 131 is a transparent layer or a translucent layer, and layer 132 is a white layer A laminated sheet in which the layer 133 is a transparent layer, a translucent layer, or a colored layer (may be a white layer)

In the above embodiment (C2-2), both the layer 131 and the layer 132 are white layers, and the case where the three

layers

131, 132, and 133 are white layers. In each layer, the content of the white colorant with respect to the thermoplastic resin including the saturated polyester resin can be in the above range, and has a concentration distribution of the white colorant from one side to the other side. It may be good or constant.

When the laminated sheet of the second aspect in the present invention has the structure shown in FIGS. 6, 7, 10, 11, 12, and 13, and the layer (C) 13 is a white layer, When the laminated sheet of the second aspect has the structure shown in FIG. 8 and the layer (C) 13a is a white layer, the laminated sheet of the second aspect of the present invention has the structure shown in FIG. In the case where the layer (C) 13a is a white layer, all have excellent reflectivity with respect to light having a wavelength of 800 to 1,400 nm, which is a preferable embodiment.

When the laminated sheet of the second aspect of the present invention has the structure shown in FIG. 8 or 9, and at least one layer constituting the layer (C) is a white layer, light having a wavelength of 800 to 1,400 nm From the viewpoint of the reflectivity for, preferred embodiments are as follows.
(C3-1) Laminated sheet (C3-2) layer 13a is a transparent layer or semi-transparent layer (C3-1) layer 13a is a white layer and layer 13b is a transparent layer, semi-transparent layer or colored layer (may be a white layer) Laminated sheet which is a transparent layer and the layer 13b is a white layer

The layer (C) may contain an additive depending on the purpose and application. Therefore, the composition containing a saturated polyester resin (hereinafter referred to as “layer (C) forming resin composition”) that forms this layer (C) may also contain an additive. This additive includes antioxidants, ultraviolet absorbers, anti-aging agents, plasticizers, fluorescent brighteners, weathering agents, fillers, antistatic agents, flame retardants, antifogging agents, antibacterial agents, antifungal agents, Antifouling agents, tackifiers and the like can be mentioned. Among these additives, specific compounds in main additives and the content ratio in the resin composition for forming a layer (C) will be described later.

When preparing the resin composition for forming the layer (C), a melt-kneading method is usually used. Examples of the apparatus used for melt kneading include a single screw extruder, a twin screw extruder, a Banbury mixer, a kneader, and a continuous kneader.

The thickness of the layer (C) is preferably 10 to 400 μm from the viewpoint of the balance of flexibility of the laminated sheet. The upper limit of the thickness is more preferably 300 μm, still more preferably 250 μm, and particularly preferably 200 μm. The lower limit of the thickness is more preferably 15 μm, still more preferably 20 μm, and particularly preferably 25 μm. In addition, when the laminated sheet of this invention is provided with two or more independent layers (C), the said thickness shall be the thickness of one layer (C).

In the laminated sheet of the first aspect of the present invention, between the layer (A) and the layer (B), between the layer (B) and the layer (C), and on the layer (C) side. Other layers 15 such as a decorative layer, a coating layer, and other resin layers can be disposed on at least one portion of the surface as desired within a range that does not impair the effects of the present invention (see FIG. 4 and FIG. 5). The other layer may be a transparent layer or a translucent layer containing ethylene / vinyl acetate resin or the like, a layer containing a fluorine-based resin, or the like. Fluorocarbon resins include ETFE (ethylene / tetrafluoroethylene copolymer), PCTEFE (trifluorinated ethylene chloride) resin, PFA (tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer), FEP (tetrafluoride). Ethylene / hexafluoropropylene copolymer), PVDF (vinylidene fluoride resin), PVF (vinyl fluoride resin) and the like.
In the present invention, the other layer 15, which is the outermost layer in FIG. 5, is a layer containing a fluorine-based resin, so that it has excellent protection against heat, external force, etc. from the other layer 15 side, and has heat resistance and flame retardancy. It is possible to obtain a laminated sheet having excellent properties, chemical resistance, weather resistance and the like.

In the first aspect of the present invention, when light is emitted to the surface of the layer (A), the layer (A) that is the light-receiving layer absorbs visible light but transmits infrared rays and is difficult to store heat. ) Or a preferred embodiment of a laminated sheet excellent in reflectivity of light transmitted through the layer (A) in both the layer (B) and the layer (C) is shown below.
[1-I] A laminated sheet having the structure shown in FIG. 1, wherein the layer (A) 11 is an infrared transparent colored resin layer containing an ethylene / vinyl acetate resin (A) and an infrared transparent colorant. Yes, the layer (B) 12 is a white layer containing an ethylene / vinyl acetate resin (B) and a white colorant, and the layer (C) 13 contains a saturated polyester resin and a white colorant. A sheet that is a white layer.
[1-II] A laminated sheet having the structure shown in FIG. 2, wherein the layer (A) 11 is an infrared transparent colored resin layer containing an ethylene / vinyl acetate resin (A) and an infrared transparent colorant. Yes, the layer (B) 12 is a white layer containing an ethylene / vinyl acetate resin (B) and a white colorant, and of the layer (C) 13, the layer 131 is a transparent layer containing a saturated polyester resin. Alternatively, a sheet which is a translucent layer and the layer 132 is a white layer containing a saturated polyester resin and a white colorant.
[1-III] A laminated sheet having the structure shown in FIG. 2, wherein the layer (A) 11 is an infrared transparent colored resin layer containing an ethylene / vinyl acetate resin (A) and an infrared transparent colorant. Yes, the layer (B) 12 is a white layer containing an ethylene / vinyl acetate resin (B) and a white colorant, and among the layers (C) 13, the layer 131 is a saturated polyester resin and a white system The sheet | seat which is a white layer containing a coloring agent and the layer 132 is a transparent layer or a translucent layer containing saturated polyester resin.
[1-IV] A laminated sheet having the structure shown in FIG. 3, wherein the layer (A) 11 is an infrared transparent colored resin layer containing an ethylene / vinyl acetate resin (A) and an infrared transparent colorant. Yes, the layer (B) 12 is a white layer containing an ethylene / vinyl acetate resin (B) and a white colorant, and among the layers (C) 13, the layer 131 is a saturated polyester resin and a white system The sheet | seat which is a white layer containing a coloring agent, the layer 132 is a transparent layer or a semi-transparent layer containing a saturated polyester resin, and the layer 133 is a white layer containing a saturated polyester resin and a white colorant.
[1-V] A laminated sheet having the structure shown in FIG. 5, wherein the layer (A) 11 is an infrared transparent colored resin layer containing an ethylene / vinyl acetate resin (A) and an infrared transparent colorant. Yes, the layer (B) 12 is a white layer containing an ethylene / vinyl acetate resin (B) and a white colorant, and the layer (C) 13 contains a saturated polyester resin and a white colorant. A sheet which is a white layer and the other layer 15 is a layer containing a fluororesin.

When the laminated sheet of the first aspect is used as a back sheet for a solar cell, from the viewpoint of photoelectric conversion efficiency, [1-I], [1-II], [1-IV] and [1-V] The sheet is particularly preferred.

In the laminated sheet of the first aspect of the present invention, the layer (A) 11, the layer (B) 12 and the layer (C) 13 may be in a continuous laminated state, or the layer (A) 11 and the layer (B) ) 12 and / or the layer (B) 12 and the layer (C) 13 may have a structure formed by bonding via an adhesive layer. Examples of the configuration of the adhesive layer include a polyurethane resin composition, an epoxy resin composition, an acrylic resin composition, and the like. In the laminated sheet of the first aspect of the present invention, the layer (A) 11 and the layer (B) 12 are in a continuous laminated state, and the layer (B) 12 and the layer (C) 13 are adhesive layers. It is preferable from the viewpoints of mechanical strength, flexibility, and the like that the structure has a structure joined through the two.

The thickness of the laminated sheet of the first aspect in the present invention is preferably 30 to 900 μm, more preferably 40 to 700 μm, from the viewpoints of flexibility, shape followability when bonded to a counterpart material, workability thereof, and the like. More preferably, it is 50 to 500 μm.

The manufacturing method of the lamination sheet of the 1st aspect in this invention is selected by the cross-sectional structure, the constituent material of each layer, etc., and is not specifically limited.
Examples of the method for producing a laminated sheet having the structure shown in FIG.
(S1) A method of co-extrusion such as a T-die cast film molding method using the layer (A) forming resin composition, the layer (B) forming resin composition, and the layer (C) forming resin composition.
(S2) A sheet or film made of the layer (A) forming resin composition, a sheet or film made of the layer (B) forming resin composition, and a sheet or film made of the layer (C) forming resin composition; Is bonded by heat fusion, dry lamination or adhesive.
(S3) The layer (A) forming resin composition and the layer (B) forming resin composition are coextruded to form a laminated sheet composed of the layer (A) and the layer (B), and then the laminated A method in which the layer (B) side surface of the sheet is bonded to the sheet or film made of the resin composition for forming the layer (C) by heat fusion, dry lamination, or an adhesive.
(S4) After performing coextrusion using the resin composition for forming the layer (B) and the resin composition for forming the layer (C) to form a laminated sheet composed of the layer (B) and the layer (C), this A method in which the layer (B) side surface of the laminated sheet and the sheet or film made of the resin composition for forming the layer (A) are bonded by heat fusion, dry lamination, or an adhesive.

Moreover, it shows below as a method of manufacturing the lamination sheet which has a structure shown in FIG.
(T1) A method of coextrusion using a layer (A) forming resin composition, a layer (B) forming resin composition, and two layer (C) forming resin compositions.
(T2) A sheet or film made of the layer (A) forming resin composition, a sheet or film made of the layer (B) forming resin composition, and a sheet or film made of the layer (C) forming resin composition ( The sheet | seat or film which consists of 131 and 132 in FIG.
(T3) After co-extrusion using the layer (A) forming resin composition and the layer (B) forming resin composition to form a laminated sheet composed of the layer (A) and the layer (B), this lamination A layer (B) side surface of the sheet and a sheet or film (sheet or film made of 131 and 132 in FIG. 2) made of the resin composition for forming the layer (C) are bonded by heat fusion, dry lamination or adhesive. How to glue.
(T4) After performing coextrusion using the resin composition for forming the layer (B) and the two resin compositions for forming the layer (C) to form a laminated sheet composed of the layer (B) and the layer (C) The layer (B) side surface of this laminated sheet and the sheet | seat or film which consists of a resin composition for layer (A) formation are adhere | attached by heat sealing | fusion, dry lamination, or an adhesive agent.

In the above methods (s1), (s3), (s4), (t1), (t3), and (t4), the conditions for performing coextrusion are selected depending on the resin composition to be used and are not particularly limited.

In the above methods (s1), (s3), (t1) and (t3), when the layer (A) forming resin composition and the layer (B) forming resin composition are used, the difference in MFR between them is The content of vinyl acetate units constituting the ethylene / vinyl acetate resin (A) contained in the resin composition for forming the layer (A) is preferably small, and the ethylene content contained in the resin composition for forming the layer (B) is preferably small. The difference between the content of vinyl acetate units constituting the vinyl acetate resin (B) and the difference in molecular weight between the ethylene / vinyl acetate resin (A) and the ethylene / vinyl acetate resin (B) must be small. preferable.
The content (m% by mass) of vinyl acetate units constituting the ethylene / vinyl acetate resin (A) contained in the layer (A) forming resin composition, and the ethylene / vinyl acetate resin contained in the layer (B) forming resin composition. The difference (| mn−) from the content (n mass%) of vinyl acetate units constituting the vinyl acetate resin (B) is preferably 20 or less, more preferably 15 or less.

A commercially available resin film (white resin film, transparent or translucent resin film) or the like may be used as the sheet or film made of the layer (C) forming resin composition.
When the layer (C) is a white layer, for example, “Lumirror E20” (trade name) manufactured by Toray Industries, “PET film U2” (trade name) manufactured by Teijin DuPont Films, etc. Can be used.
When the layer (C) is composed of a white layer and a translucent layer, “Teijin Tetron Film VW” (product of Teijin DuPont Films), which is a laminated film in which a white PET layer and a translucent PET layer are laminated Name) etc. can be used.
In addition, as transparent or translucent resin films, “Melinex 238” (trade name) manufactured by Teijin DuPont, “SR55” (trade name) manufactured by SKC, “Lumirror X10P”, “Lumirror S10” and “Lumirror” manufactured by Toray Industries, Inc. X10S ”(above, product name).
In addition, when forming a layer (C) using a commercially available resin film, it is on the surface by the side of the layer (C) in the laminated sheet of the 1st aspect in this invention to use the resin film which has a flame retardance. From the viewpoint of fire resistance, it is preferable. The flame retardancy of the resin film having flame retardancy is preferably UL94VTM-2 class or higher.
In addition, when the second embodiment of the present invention shown in FIGS. 6 to 10 and 12 is used with a commercially available resin film, fire resistance from the opposite side of the layer (A) can be obtained. Therefore, it is preferable to use a resin film having flame retardancy. The flame retardancy of the resin film having flame retardancy is preferably UL94VTM-2 class or higher.
In forming the layer (C), a plurality of the above-mentioned commercially available white resin films can be used, and the above-mentioned commercially available white resin film and a commercially available transparent or translucent resin film are combined. It can also be used.

The laminated sheet according to the second aspect of the present invention further includes a water vapor barrier layer (D) as an intermediate layer (see FIGS. 6 to 13).

The water vapor barrier layer (D) is formed between the layer (A) and the layer (B), between the layer (B) and the layer (C), and when the layer (C) is composed of two or more. It can be located in at least one selected from among at least one of them. Among these, it is preferable to provide between the said layer (B) and the said layer (C), and to provide between the said several layer (C).

The water vapor barrier layer (D) preferably has a moisture permeability (hereinafter also referred to as “water vapor permeability”) measured under conditions of a temperature of 40 ° C. and a humidity of 90% RH according to JIS K7129, preferably 3 g / (m ² · day) or less, more preferably 1 g / (m ² · day) or less, and even more preferably 0.7 g / (m ² · day) or less.
The water vapor barrier layer (D) is preferably a layer made of a material having electrical insulation.

The water vapor barrier layer (D) may have a single layer structure or a multilayer structure made of one kind of material, or a multilayer structure made of two or more kinds of materials. In the present invention, it is a water vapor barrier layer (D) obtained using a vapor deposition film (two-layer film) in which a film (layer) made of metal and / or metal oxide is formed on the surface of a resin layer. It is preferable. Both the metal and the metal oxide may be a single substance or two or more kinds.

Examples of the metal include aluminum.
Examples of the metal compound include oxides of elements such as silicon, aluminum, magnesium, calcium, potassium, tin, sodium, boron, titanium, lead, zirconium, and yttrium. Of these, silicon oxide, aluminum oxide, and the like are particularly preferable from the viewpoint of water vapor barrier properties.
The film (layer) made of the metal and / or metal oxide may be formed by a method such as plating, vacuum deposition, ion plating, sputtering, plasma CVD, or microwave CVD. Two or more of these methods may be combined.

As the resin layer in the vapor deposition film, polyester film such as polyethylene terephthalate film and polyethylene naphthalate; polyolefin film such as polyethylene and polypropylene; polyvinylidene chloride film, polyvinyl chloride film, fluorine resin film, polysulfone film, polystyrene film, Examples thereof include a polyamide film, a polycarbonate film, a polyacrylonitrile film, and a polyimide film. The thickness of this resin layer is preferably 5 to 50 μm, more preferably 8 to 20 μm.

As the above-mentioned two-layer film, commercially available “Tech Barrier AX” and “Tech Barrier LX” (trade name) manufactured by Mitsubishi Plastics, “GX Film” (trade name) manufactured by Toppan Printing Co., Ltd., Toyobo “Ecosia VE500” (trade name) manufactured by the company can be used, and these can be used as a film for forming a water vapor barrier layer (D).

When the water vapor barrier layer (D) is a two-layer type comprising a resin layer and a film (layer) made of a metal and / or metal oxide, the resin layer is located on the layer (A) side. It may be located on the opposite side of the layer (A). In addition, also when a water vapor | steam barrier layer (D) exists between two layers (C), the said resin layer may be located in the side in which a layer (A) exists, and it is located in the other side. Also good.

As the film for forming the water vapor barrier layer (D), a three-layer film can also be used. This three-layer film can be a laminated film in which a film (layer) made of a metal and / or a metal oxide is disposed between an upper resin layer and a lower resin layer.

The thickness of the water vapor barrier layer (D) is preferably 5 to 300 μm, more preferably 8 to 250 μm, still more preferably 10 to 200 μm. In addition, when the lamination sheet of the 2nd aspect in this invention is provided with two or more independent water vapor | steam barrier layers (D), the said thickness shall be the thickness of one layer (D). If the water vapor barrier layer (D) is too thin, the water vapor barrier property from one side to the other side may be insufficient, and if it is too thick, the flexibility as a laminated sheet may not be sufficient.

In the laminated sheet of the second aspect of the present invention, the layer (A), the layer (B) and the layer (C), and the water vapor barrier layer (D) may be in a continuous laminated state regardless of the order thereof. , Layer (A) and layer (B), layer (B) and layer (C), layer (A) and water vapor barrier layer (D), layer (B) and water vapor barrier layer (D), and layer (C ) And the water vapor barrier layer (D) may have a structure formed by bonding via an adhesive layer. Examples of the configuration of the adhesive layer include a polyurethane resin composition, an epoxy resin composition, an acrylic resin composition, and the like. The same applies when other layers are provided.

In addition, the laminated sheet of the 2nd aspect in this invention is a range which does not impair the effect of this invention, and can provide other layers 15, such as a decoration layer, an application layer, and another resin layer, as mentioned above. . The other layer may be a transparent layer or a semi-transparent layer containing ethylene / vinyl acetate resin, a resin layer containing a thermoplastic resin excluding a saturated polyester resin, a layer containing a fluorine resin, or the like. Fluorocarbon resins include ETFE (ethylene / tetrafluoroethylene copolymer), PCTEFE (trifluorinated ethylene chloride) resin, PFA (tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer), FEP (tetrafluoride). Ethylene / hexafluoropropylene copolymer), PVDF (vinylidene fluoride resin), PVF (vinyl fluoride resin) and the like.
In the present invention, the other layer 15, which is the outermost layer in FIGS. 11 and 13, is a layer containing a fluorine-based resin, thereby providing excellent protection against heat, external force, etc. from the other layer 15 side, and heat resistance. In addition, a laminated sheet excellent in flame retardancy, chemical resistance, weather resistance and the like can be obtained.

In the second aspect of the present invention, when light is radiated to the surface of the layer (A), the layer (A) which is the light receiving layer absorbs visible light but transmits infrared rays and hardly stores heat. ) Or a preferred embodiment of a laminated sheet excellent in reflectivity of light transmitted through the layer (A) in both the layer (B) and the layer (C) is shown below.
[2-I] A laminated sheet having the structure shown in FIG. 6, wherein the layer (A) 11 is an infrared transparent colored resin layer containing an ethylene / vinyl acetate resin (A) and an infrared transparent colorant. Yes, the layer (B) 12 is a white layer containing an ethylene / vinyl acetate resin (B) and a white colorant, and the layer (C) 13 is a white layer or a translucent layer containing a saturated polyester resin The water vapor barrier layer (D) 14 has a two-layer structure including a resin layer and a film (layer) containing a metal and / or a metal oxide.
[2-II] A laminated sheet having the structure shown in FIG. 7, wherein the layer (A) 11 is an infrared transparent colored resin layer containing an ethylene / vinyl acetate resin (A) and an infrared transparent colorant. A transparent layer or translucent layer in which layer (B) 12 is a white layer containing ethylene / vinyl acetate resin (B) and a white colorant, and layer (C) 13 contains a saturated polyester resin The water vapor barrier layer (D) 14 has a two-layer structure including a resin layer and a film (layer) containing a metal and / or a metal oxide.
[2-III] A laminated sheet having the structure shown in FIG. 8 or 9, wherein the layer (A) 11 includes an ethylene / vinyl acetate resin (A) and an infrared transparent colorant. It is a resin layer, the layer (B) 12 is a white layer containing an ethylene-vinyl acetate resin (B) and a white colorant, and among the layers (C) 13, the layer 13a is a saturated polyester resin , A white layer containing a white colorant, the layer 13b is a transparent layer, a translucent layer or a white layer containing a saturated polyester resin, a water vapor barrier layer (D) 14 is a resin layer, a metal and A sheet having a two-layer structure comprising a film (layer) containing a metal oxide.
[2-IV] A laminated sheet having the structure shown in FIG. 10, wherein the layer (A) 11 is an infrared transparent colored resin layer containing an ethylene / vinyl acetate resin (A) and an infrared transparent colorant. Yes, the layer (B) 12 is a white layer containing an ethylene / vinyl acetate resin (B) and a white colorant, and the layer (C) 13 contains a saturated polyester resin and a white colorant. A sheet which is a white layer and has a two-layer structure in which the water vapor barrier layers (D) 14a and 14b are the same or different from each other and are composed of a resin layer and a film (layer) containing a metal and / or a metal oxide.
[2-V] A laminated sheet having the structure shown in FIG. 11, wherein the layer (A) 11 is an infrared transparent colored resin layer containing an ethylene / vinyl acetate resin (A) and an infrared transparent colorant. A transparent layer or translucent layer in which layer (B) 12 is a white layer containing ethylene / vinyl acetate resin (B) and a white colorant, and layer (C) 13 contains a saturated polyester resin The water vapor barrier layer (D) 14 has a two-layer structure including a resin layer and a film (layer) containing a metal and / or metal oxide, and the other layer 15 is heat excluding the saturated polyester resin. A sheet which is a resin layer containing a plastic resin.
[2-VI] A laminated sheet having the structure shown in FIG. 12, wherein the layer (A) 11 is an infrared transparent colored resin layer containing an ethylene / vinyl acetate resin (A) and an infrared transparent colorant. A transparent layer or translucent layer in which layer (B) 12 is a white layer containing ethylene / vinyl acetate resin (B) and a white colorant, and layer (C) 13 contains a saturated polyester resin The water vapor barrier layer (D) 14 has a two-layer structure including a resin layer and a film (layer) containing a metal and / or metal oxide, and the other layer 15 is heat excluding the saturated polyester resin. A sheet which is a resin layer containing a plastic resin.
[2-VII] A laminated sheet having the structure shown in FIG. 13, wherein the layer (A) 11 is an infrared transparent colored resin layer containing an ethylene / vinyl acetate resin (A) and an infrared transparent colorant. A transparent layer or translucent layer in which layer (B) 12 is a white layer containing ethylene / vinyl acetate resin (B) and a white colorant, and layer (C) 13 contains a saturated polyester resin The water vapor barrier layer (D) 14 has a two-layer structure including a resin layer and a film (layer) containing a metal and / or metal oxide, and the other layer 15 is heat excluding the saturated polyester resin. A sheet which is a resin layer containing a plastic resin.

In these embodiments, the layer (C) can be composed of two or more continuous layers, a combination of only white layers, a combination of white layers and transparent layers, a combination of white layers and translucent layers, and translucent. A combination of a layer and a semi-transparent layer, a combination of a transparent layer and a semi-transparent layer, and the like.

Examples of laminated sheets other than those described above are exemplified below.
[2-VIII] layer (A), first water vapor barrier layer (D1), layer (B), part of the layers constituting layer (C), second water vapor barrier layer (D2), The sheet | seat provided with the other layer which comprises a layer (C) sequentially.
[2-IX] layer (A), layer (B), first water vapor barrier layer (D1), a part of layers constituting layer (C), second water vapor barrier layer (D2), The sheet | seat provided with the other layer which comprises a layer (C) sequentially.
[2-X] a layer (A), a first water vapor barrier layer (D1), a layer (B), a second water vapor barrier layer (D2), a part of the layers constituting the layer (C), A sheet comprising a third water vapor barrier layer (D3) and another layer constituting the layer (C) in sequence.
[2-XI] A laminated sheet having the structure shown in FIG. 11, wherein the layer (A) 11 is an infrared transparent colored resin layer containing an ethylene / vinyl acetate resin (A) and an infrared transparent colorant. A transparent layer or translucent layer in which layer (B) 12 is a white layer containing ethylene / vinyl acetate resin (B) and a white colorant, and layer (C) 13 contains a saturated polyester resin The water vapor barrier layer (D) 14 has a two-layer structure including a resin layer and a film (layer) containing a metal and / or a metal oxide, and the other layer 15 is a resin containing a fluorine-based resin. A sheet that is a layer.
[2-XII] A laminated sheet having the structure shown in FIG. 13, wherein the layer (A) 11 is an infrared transparent colored resin layer containing an ethylene / vinyl acetate resin (A) and an infrared transparent colorant. A transparent layer or translucent layer in which layer (B) 12 is a white layer containing ethylene / vinyl acetate resin (B) and a white colorant, and layer (C) 13 contains a saturated polyester resin The water vapor barrier layer (D) 14 has a two-layer structure including a resin layer and a film (layer) containing a metal and / or a metal oxide, and the other layer 15 is a resin containing a fluorine-based resin. A sheet that is a layer.

When the laminated sheet of the second aspect is used as a solar cell back sheet, any of them is preferable from the viewpoint of photoelectric conversion efficiency.

The thickness of the laminated sheet of the second aspect in the present invention is preferably 30 to 900 μm, more preferably 40 to 700 μm, from the viewpoints of flexibility, shape followability when bonded to a counterpart material, workability thereof, and the like. More preferably, it is 50 to 500 μm.

The method for producing the laminated sheet of the second aspect in the present invention is not particularly limited, and is selected depending on the cross-sectional structure, the constituent material of each layer, and the like.

As the method for producing the laminated sheet of the above embodiment [2-I], for example, a layer (A) forming sheet (or film) containing the layer (A) forming resin composition and a water vapor barrier layer (D) forming After the film is bonded by heat fusion or dry lamination or an adhesive to form a first laminated sheet, the water vapor barrier layer (D) side surface of this first laminated sheet and the layer (B) forming sheet (or Film) is bonded with an adhesive to form a second laminated sheet, and then the layer (B) side surface of the second laminated sheet and the layer (C) forming sheet (or film) are bonded with an adhesive. The method of joining is mentioned.

As a method for producing the laminated sheet of the above embodiment [2-II], for example, using a resin composition for forming a layer (A) and a resin composition for forming a layer (B), a common method such as a T-die cast film forming method can be used. Extrusion was performed to produce a laminated film composed of the layer (A) and the layer (B), and then the layer (B) side surface of the laminated film and the water vapor barrier layer (D) forming film were heat-sealed. Alternatively, the first laminated sheet is bonded by dry lamination or an adhesive, and then the water vapor barrier layer (D) side surface and the layer (C) forming sheet (or film) in the first laminated sheet are bonded with an adhesive. Examples include a joining method.

A method for producing the laminated sheet of the above embodiment [2-III] shown in FIG. 8, for example, is to produce a laminated film comprising a layer (A) and a layer (B) in the same manner as described above. After that, the layer (B) side surface in this laminated film and the film for forming the water vapor barrier layer (D) are joined by heat fusion, dry lamination or an adhesive to form a first laminated sheet, The water vapor barrier layer (D) side surface of one laminated sheet and the sheet (or film) for forming one layer (C) are joined by heat fusion, dry lamination or adhesive to form a second laminated sheet, and then A method of joining the surface of the layer (C) side in the second laminated sheet and the sheet (or film) for forming another layer (C) with an adhesive or the like. In addition, you may join the sheet | seat (or film) for layer (C) formation provided with the two resin layers which all contain saturated polyester resin to the water vapor | steam barrier layer (D) side surface in a 1st lamination sheet.
A method for producing the laminated sheet of the above embodiment [2-III] shown in FIG. 9, for example, is to produce a laminated film comprising layers (A) and (B) in the same manner as described above. Then, the layer (B) side surface in this laminated film and the sheet (or film) for forming one layer (C) are joined by thermal fusion, dry lamination or an adhesive to form a first laminated sheet, Next, the layer (C) side surface of the first laminated sheet and the water vapor barrier layer (D) forming film are joined by heat fusion, dry lamination or adhesive to form a second laminated sheet, and then The method etc. which join the water vapor | steam barrier layer (D) side surface in a 2nd lamination sheet, and the sheet | seat (or film) for formation of another layer (C) with an adhesive agent etc. are mentioned.

As a method for producing the laminated sheet of the above embodiment [2-IV], for example, a layer (A) forming sheet (or film) and a first water vapor barrier layer (D1) forming film are heat-sealed or dried. After bonding with a laminate or an adhesive to form a first laminated sheet, the first water vapor barrier layer (D1) side surface of the first laminated sheet and the layer (B) forming sheet (or film) are bonded to the adhesive. To form a second laminated sheet, and then the layer (B) side surface of the second laminated sheet and the second water vapor barrier layer (D2) forming film are bonded by heat fusion, dry lamination or adhesive. The third laminated sheet is bonded, and then the second water vapor barrier layer (D2) side surface of the third laminated sheet and the layer (C) forming sheet (or film) are bonded to the adhesive. The method or the like to further bonding and the like.

As a method for producing the laminated sheet of the above embodiment [2-V], for example, a layer (A) forming sheet (or film) and a first water vapor barrier layer (D1) forming film are heat-sealed or dried. After bonding with a laminate or an adhesive to form a first laminated sheet, the first water vapor barrier layer (D1) side surface of the first laminated sheet and the layer (B) forming sheet (or film) are bonded to the adhesive. To form a second laminated sheet, and then the layer (B) side surface of this second laminated sheet and the sheet (or film) for forming one layer (C) are heat-sealed, dry laminated or bonded The third laminated sheet is joined by an agent, and then the layer (C) side surface of this third laminated sheet and the film for forming the second water vapor barrier layer (D2) are heat-sealed or dry laminated. Alternatively, the fourth laminated sheet is joined by an adhesive, and then the second water vapor barrier layer (D2) side surface of the fourth laminated sheet is bonded to the other layer (C) forming sheet (or film). The method of joining with an agent is mentioned.

As a method for producing the laminated sheet of the above embodiment [2-VI], for example, after producing a first laminated film comprising a layer (A) and a layer (B) in the same manner as described above, The layer (B) side surface and the film for forming the first water vapor barrier layer (D1) are joined by heat fusion, dry lamination, or an adhesive to form a second laminated sheet, and then the second laminated sheet in the second laminated sheet The 1st water vapor barrier layer (D1) side surface and the 1st layer (C) formation sheet (or film) are joined by heat fusion, dry lamination, or adhesives, and it is set as the 3rd lamination sheet, and then this 1st The layer (C) side surface of the 3 laminated sheet and the film for forming the second water vapor barrier layer (D2) are joined by heat fusion, dry lamination or adhesive to form a 4th laminated sheet, And the fourth second water vapor barrier layer in the laminated sheet (D2) side surfaces, a method, and the like to bond the other layers (C) forming sheet (or film) and an adhesive.

As a method for producing the sheet of the above embodiment [2-VII], for example, a layer (A) forming sheet (or film) and a first water vapor barrier layer (D1) forming film are heat-sealed or dry laminated. Alternatively, after bonding with an adhesive to form the first laminated sheet, the first water vapor barrier layer (D1) side surface of the first laminated sheet and the layer (B) forming sheet (or film) are bonded with the adhesive. Next, the layer (B) side surface of the second laminated sheet and the film for forming the second water vapor barrier layer (D2) are joined by heat fusion, dry lamination, or an adhesive. Then, a third laminated sheet is formed, and then the second water vapor barrier layer (D2) side surface of this third laminated sheet and one layer (C) forming sheet (or film) are thermally fused. Or it is joined by dry lamination or an adhesive to form a fourth laminated sheet, and then the layer (C) side surface of the fourth laminated sheet and the film for forming the third water vapor barrier layer (D3) are heat-sealed or The fifth laminated sheet is bonded by dry lamination or an adhesive, and then the third water vapor barrier layer (D3) side surface of the fifth laminated sheet and the other layer (C) forming sheet (or film) are combined. The method of joining with an adhesive agent etc. are mentioned.

The method for producing the sheet of the above embodiment [2-VIII], [2-IX] and [2-X] can be the same as the production method of the above embodiment [2-II] or [2-III].
In addition, the manufacturing method of the sheet of the above embodiments [2-XI] and [2-XII] can be the same as the manufacturing method of the above embodiments [2-V] and [2-VII], respectively.

In the method for producing the laminated sheet of the second aspect, when the layer (A) forming resin composition and the layer (B) forming resin composition are used, the difference in MFR between the two is preferably small. (A) The content of vinyl acetate units constituting the ethylene / vinyl acetate resin (A) contained in the forming resin composition and the ethylene / vinyl acetate resin (B) contained in the layer (B) forming resin composition It is preferable that both the difference from the content of the vinyl acetate unit constituting and the difference in molecular weight between the ethylene / vinyl acetate resin (A) and the ethylene / vinyl acetate resin (B) are small.
The content (m% by mass) of vinyl acetate units constituting the ethylene / vinyl acetate resin (A) contained in the layer (A) forming resin composition, and the ethylene / vinyl acetate resin contained in the layer (B) forming resin composition. The difference (| mn−) from the content (n mass%) of vinyl acetate units constituting the vinyl acetate resin (B) is preferably 20 or less, more preferably 15 or less.

In the laminated sheets of the first and second aspects of the present invention, when light having a wavelength of 400 to 700 nm is radiated to the surface of the layer (A) in the laminated sheet, the light absorption rate is preferably 60% or more, More preferably, it is 70% or more, More preferably, it is 80% or more. The higher the absorptance, the lower the brightness of the laminated sheet as viewed from the layer (A) side, and the laminated sheet can exhibit a dark color system. Thereby, when the transparent or semi-transparent counterpart material and the surface of the layer (A) are bonded to form an integrated product, the appearance and design properties seen from the counterpart material side are excellent. For example, the laminate sheet of the present invention is used as a solar cell backsheet, the surface of the layer (A) and the solar cell element (s) are embedded, and the gap contains an ethylene / vinyl acetate resin or the like. When the solar cell module is made by adhering to the filler part (exposed surface) filled with the object, and then made into a solar cell, the appearance and design of the solar cell arranged on the roof of the house etc. Excellent. “Absorptivity with respect to light having a wavelength of 400 to 700 nm is 60% or more” means that the absorptance of light in the wavelength region from 400 nm to 700 nm is measured every 400 nm or from 700 nm to 20 nm, It means that the calculated average value is 60% or more, and it does not require that the light absorption rate in the wavelength range is 60% or more.

In the laminated sheets of the first and second aspects of the present invention, when light having a wavelength of 800 to 1,400 nm is radiated to the surface of the layer (A) in the laminated sheet, the reflectance with respect to this light is preferably It is 50% or more, more preferably 60% or more, and further preferably 70% or more. The higher the reflectance, the more light having at least the wavelength can be reflected toward the layer (A) side. For example, when the laminated sheet of the present invention is used as a back sheet for a solar cell to produce a solar cell module, at least light having the above wavelength can be reflected toward the solar cell element, improving the photoelectric conversion efficiency. Can be made. “Reflectance for light with a wavelength of 800 to 1,400 nm is 50% or more” means that the reflectance of light in the wavelength range from 800 nm to 1,400 nm is measured every 800 nm or from 1,400 nm to 20 nm. In addition, it means that the average value calculated using each reflectance is 50% or more, and it does not require that all the reflectances of light in the wavelength range are 50% or more.

In the laminated sheet having these preferable performances, 60% or more of light having a wavelength of 400 to 700 nm emitted to the surface of the layer (A) is absorbed by the layer (A), and light having a wavelength of 800 to 1,400 nm is absorbed. When the light passes through and reaches the layer (B), the light can be sufficiently reflected by at least the layer (B), and the occurrence of thermal deformation due to the light can be suppressed. The laminated sheet is used as a back sheet for a solar cell, and the surface of the layer (A) is embedded with a plurality of solar cell elements, and the gap is filled with a composition containing ethylene / vinyl acetate resin or the like. When the solar cell module is bonded to the formed filler portion (exposed surface thereof), the reflected light from the layer (B) can be used for photoelectric conversion to improve power generation efficiency.

The laminated sheet of the second aspect of the present invention is excellent in water vapor barrier properties from one side to the other side, and the water vapor permeability of the sheet is a condition of a temperature of 40 ° C. and a humidity of 90% RH according to JIS K7129. In any case, it is preferably 3 g / (m ² · day) or less, more preferably 1 g / (m ² · day) or less. Because of having the above performance, when using this laminated sheet to produce a solar cell module, it is possible to suppress deterioration of the solar cell element due to the intrusion of water, water vapor, etc., and further decrease in power generation efficiency. Excellent durability.

Next, the additives contained in the layer (A), the layer (B) and the layer (C) will be described.

Examples of the antioxidant include hindered amine compounds, hydroquinone compounds, hindered phenol compounds, sulfur-containing compounds, and phosphorus-containing compounds. These can be used alone or in combination of two or more.
The content of the antioxidant is preferably 0.05 to 10% by mass with respect to the entire layer (A), the entire layer (B), or the entire layer (C). is there. In addition, as for this ratio, all are the layer (A) formation resin composition which forms the said layer (A), the layer (B) formation resin composition which forms the said layer (B), and the said layer ( It can be made into the ratio with respect to the resin composition for layer (C) formation which forms C). The same applies to other additives.

Examples of ultraviolet absorbers include benzophenone compounds, benzotriazole compounds, and triazine compounds. These can be used alone or in combination of two or more.
The content of the ultraviolet absorber is preferably 0.05 to 10% by mass with respect to the entire layer (A), the entire layer (B), or the entire layer (C). is there.

Antiaging agents include naphthylamine compounds, diphenylamine compounds, p-phenylenediamine compounds, quinoline compounds, hydroquinone derivative compounds, monophenol compounds, bisphenol compounds, trisphenol compounds, polyphenol compounds, thiobisphenols. Compounds, hindered phenol compounds, phosphite compounds, imidazole compounds, nickel dithiocarbamate salts, phosphate compounds and the like. These can be used alone or in combination of two or more.
The content of the anti-aging agent is preferably 0.05 to 10% by mass with respect to the entire layer (A), the entire layer (B), or the entire layer (C), respectively. is there.

Examples of the plasticizer include phthalates such as dimethyl phthalate, diethyl phthalate, dibutyl phthalate, diisobutyl phthalate, dioctyl phthalate, butyl octyl phthalate, di- (2-ethylhexyl) phthalate, diisooctyl phthalate, diisodecyl phthalate; dimethyl adipate, Diisobutyl adipate, di- (2-ethylhexyl) adipate, diisooctyl adipate, diisodecyl adipate, octyl decyl adipate, di- (2-ethylhexyl) azelate, diisooctyl azelate, diisobutyl azelate, dibutyl sebacate, di- ( 2-ethylhexyl) fatty acid esters such as sebacate, diisooctyl sebacate; trimellitic acid isodecyl ester, trimellitic octyl ester Trimellitic acid esters such as tellurium, trimellitic acid n-octyl ester, trimellitic acid isononyl ester; di- (2-ethylhexyl) fumarate, diethylene glycol monooleate, glyceryl monoricinoleate, trilauryl phosphate, tristearyl phosphate, Examples include tri- (2-ethylhexyl) phosphate, epoxidized soybean oil and the like. These can be used alone or in combination of two or more.
The content of the plasticizer is preferably 0.05 to 10% by mass with respect to the entire layer (A), the entire layer (B), or the entire layer (C). .

Examples of the flame retardant include organic flame retardants, inorganic flame retardants, and reactive flame retardants. These can be used alone or in combination of two or more.
Organic flame retardants include brominated epoxy compounds, brominated alkyltriazine compounds, brominated bisphenol epoxy resins, brominated bisphenol phenoxy resins, brominated bisphenol polycarbonate resins, brominated polystyrene resins, brominated crosslinked polystyrene resins Halogenated flame retardants such as brominated bisphenol cyanurate resin, brominated polyphenylene ether, decabromodiphenyl oxide, tetrabromobisphenol A and oligomers thereof; trimethyl phosphate, triethyl phosphate, tripropyl phosphate, tributyl phosphate, tripentyl phosphate, toki Hexyl phosphate, tricyclohexyl phosphate, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate Phosphate esters such as phosphate, cresyl diphenyl phosphate, dicresyl phenyl phosphate, dimethyl ethyl phosphate, methyl dibutyl phosphate, ethyl dipropyl phosphate, hydroxyphenyl diphenyl phosphate, compounds modified with these substituents, various condensed types Phosphorus ester compounds, phosphorus flame retardants such as phosphazene derivatives containing phosphorus and nitrogen elements; polytetrafluoroethylene, guanidine salts, silicone compounds, and the like. These can be used alone or in combination of two or more.

Examples of the inorganic flame retardant include aluminum hydroxide, antimony oxide, magnesium hydroxide, zinc borate, zirconium compound, molybdenum compound, and zinc stannate. These can be used alone or in combination of two or more.
Reactive flame retardants include tetrabromobisphenol A, dibromophenol glycidyl ether, brominated aromatic triazine, tribromophenol, tetrabromophthalate, tetrachlorophthalic anhydride, dibromoneopentyl glycol, poly (pentabromobenzyl polyacrylate) , Chlorendic acid (hett acid), chlorendic anhydride (hett acid anhydride), brominated phenol glycidyl ether, dibromocresyl glycidyl ether and the like. These can be used alone or in combination of two or more.

The content of the flame retardant is preferably 10% by mass or less with respect to the entire layer (A), the entire layer (B), or the entire layer (C).
It is difficult to add a flame retardant to a thermoplastic resin composition such as the layer (A) forming resin composition, the layer (B) forming resin composition, and the layer (C) forming resin composition. It is preferable to use a fuel aid together. As this flame retardant auxiliary, antimony trioxide, antimony tetroxide, antimony pentoxide, sodium antimonate, antimony tartrate, antimony compounds, zinc borate, barium metaborate, hydrated alumina, zirconium oxide, Examples include ammonium polyphosphate and tin oxide. These may be used alone or in combination of two or more.

When using the lamination sheet of this invention as a solar cell backsheet, the schematic of a solar cell module provided with the lamination sheet of this invention is shown by FIG.
The solar cell module 2 in FIG. 14 includes a surface-side transparent protective member 21, a surface-side sealing film (surface-side filler) 23, a solar cell element 25, and a back surface side from the sunlight receiving surface side (upper side in the drawing). The sealing film (back surface side filler part) 27 and the laminated sheet 1 of the present invention may be arranged in this order. In addition, the solar cell module of this invention can also be equipped with various members as needed other than the said component as needed as needed (not shown).

As the said surface side transparent protection member 21, what consists of a material excellent in water vapor | steam barrier property is preferable, and the transparent substrate which consists of glass, resin, etc. is used normally. Although glass is excellent in transparency and weather resistance, a weather-resistant transparent resin (resin composition containing a fluorine-based resin or the like) is preferable from the viewpoint of impact resistance, workability, and the like. When a transparent resin is used as the surface-side transparent protective member 21, the solar cell can be reduced in weight. Therefore, when the solar cell is placed on the roof of a house, excellent workability is obtained during installation. Can do.
The thickness of the surface side transparent protective member 21 is usually about 1 to 5 mm when glass is used, and is usually about 0.1 to 5 mm when transparent resin is used.

The solar cell element 25 has a power generation function by receiving sunlight. As such a solar cell element, if it has a function as a photovoltaic power, it will not be specifically limited, A well-known thing can be used. For example, a crystalline silicon solar cell element such as a single crystal silicon type solar cell element or a polycrystalline silicon type solar cell element; an amorphous silicon solar cell element composed of a single bond type or a tandem structure type; gallium arsenide (GaAs) or indium phosphorus ( III-V compound semiconductor solar cell elements such as InP); II-VI compound semiconductor solar cell elements such as cadmium tellurium (CdTe) and copper indium selenide (CuInSe ₂ ). Of these, a crystalline silicon solar cell element is preferable, and a polycrystalline silicon solar cell element is particularly preferable. A thin film polycrystalline silicon solar cell element, a thin film microcrystalline silicon solar cell element, a hybrid element of a thin film crystalline silicon solar cell element and an amorphous silicon solar cell element, or the like can be used.

Although not shown in FIG. 14, the solar cell element 25 usually includes a wiring electrode and a take-out electrode. The wiring electrode has an action of collecting electrons generated in the plurality of solar cell elements by receiving sunlight, for example, a solar cell element on the surface side sealing film (surface side filler part) 21 side, It connects so that the solar cell element by the side of the back surface side sealing film (back surface side filler material part) 27 side may be connected. The take-out electrode has an action of taking out electrons collected by the wiring electrode or the like as a current.

The front-side sealing film (front-side filler part) 21 and the back-side sealing film (back-side filler part) 27 (hereinafter collectively referred to as “sealing film”) are usually identical to each other. Alternatively, after using a different sealing film forming material to form a sheet-shaped or film-shaped sealing film in advance, the solar cell element 25 and the like are thermocompression bonded between the surface-side transparent protective member 21 and the laminated sheet 1. Formed.
The thickness of each sealing film (filler part) is usually about 100 μm to 4 mm, preferably about 200 μm to 3 mm, more preferably about 300 μm to 2 mm. If the thickness is too thin, the solar cell element 25 may be damaged. On the other hand, if the thickness is too large, the manufacturing cost increases, which is not preferable.

The sealing film forming material is usually a resin composition or a rubber composition. Examples of the resin include an olefin resin, an epoxy resin, a polyvinyl butyral resin, and the like. Examples of the rubber include silicone rubber and hydrogenated conjugated diene rubber. Of these, olefin resins and hydrogenated conjugated diene rubbers are preferred.

Examples of olefin resins include olefins such as ethylene, propylene, butadiene, and isoprene, or polymers obtained by polymerizing diolefins, and ethylene and other monomers such as vinyl acetate and acrylate esters. Copolymers, ionomers and the like can be used. Specific examples include polyethylene, polypropylene, polymethylpentene, ethylene / vinyl chloride copolymer, ethylene / vinyl acetate resin, ethylene / (meth) acrylic acid ester copolymer, ethylene / vinyl alcohol copolymer, chlorinated polyethylene. And chlorinated polypropylene. Of these, ethylene / vinyl acetate resins and ethylene / (meth) acrylic acid ester copolymers are preferable, and ethylene / vinyl acetate resins are particularly preferable. It is important for the sealing film forming material made of a resin composition containing ethylene / vinyl acetate resin or the like to be excellent in transparency when the solar battery cell receives sunlight.

Examples of hydrogenated conjugated diene rubber include hydrogenated styrene / butadiene rubber, styrene / ethylene butylene / olefin crystal block polymer, olefin crystal / ethylene butylene / olefin crystal block polymer, styrene / ethylene butylene / styrene block polymer, and the like. It is done. Preferably, a hydrogenated conjugated diene block copolymer having the following structure, that is, a polymer block A containing an aromatic vinyl compound unit; a conjugated diene compound having a 1,2-vinyl bond content exceeding 25 mol% Polymer block B obtained by hydrogenating at least 80 mol% of a double bond portion of a polymer containing units; Polymer double containing a conjugated diene compound unit having a 1,2-vinyl bond content of 25 mol% or less Polymer block C obtained by hydrogenating 80 mol% or more of the bonded portion; and a polymer block C obtained by hydrogenating 80 mol% or more of the double bond portion of the copolymer containing the aromatic vinyl compound unit and the conjugated diene compound unit. It is a block copolymer having at least two selected from the combined block D.

The sealing film-forming material may contain a crosslinking agent, a crosslinking aid, a silane coupling agent, an ultraviolet absorber, a hindered phenol-based or phosphite-based antioxidant, a hindered amine-based light stabilizer, a light as necessary. Additives such as a diffusing agent, a flame retardant, and a discoloration preventing agent can be contained.
As described above, the material for forming the front surface side sealing film (front surface side filler portion) 23 and the material for forming the back surface side sealing film (back surface side filler portion) 27 are the same or different. However, the same is preferable from the viewpoint of adhesiveness.

In the solar cell module of the present invention, for example, after arranging the surface side transparent protective member, the surface side sealing film, the solar cell element, the back surface side sealing film and the laminated sheet of the present invention in this order, these are integrated. Further, it can be manufactured by a lamination method or the like in which heat-pressure bonding is performed while vacuum suction is performed.
The lamination temperature in this lamination method is usually about 100 ° C. to 250 ° C. from the viewpoint of adhesion of the laminated sheet of the present invention. The laminating time is usually about 3 to 30 minutes.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to such examples as long as the gist of the present invention is not exceeded. In the following, “part” and “%” are based on mass unless otherwise specified.

1. Evaluation method Measurement methods for various evaluation items are shown below.

1-1. Dimensional change rate (heat resistance)
A laminated sheet (thickness is described in the table) was cut to prepare a test piece having a size of 120 mm (MD; resin extrusion direction) × 120 mm (TD; direction orthogonal to MD). Next, a square mark of 100 mm (MD) × 100 mm (TD) was drawn at the center of the test piece, and left at 130 ° C. for 30 minutes in a thermostatic bath. Then, it cooled, the length in the said marked line was measured, and the dimensional change rate was computed from the following formula.

1-2. Adhesiveness with Ethylene / Vinyl Acetate Resin Film As described above, when the laminated sheet is used as a member constituting a solar cell module (back sheet for solar cell), the laminated sheet is formed on the surface of the layer (A), It can be used for bonding a back surface side sealing film formed by embedding a solar cell element included in the solar cell module. Since the ethylene / vinyl acetate resin composition is widely used as a material for forming the back surface side sealing film, the surface of the layer (A) in the laminated sheet is adhered to the following ethylene / vinyl acetate resin film. These adhesive properties were evaluated.
The laminated sheet was cut into a strip shape (length 200 mm, width 15 mm, thickness described in the table), and two evaluation sheets were obtained. An ethylene / vinyl acetate resin film (trade name “Ultra Pearl”, manufactured by Sanvic Co., Ltd.) having a length of 100 mm, a width of 15 mm and a thickness of 400 μm is positioned between the layers (A) of the two evaluation sheets. And placed in a laminator in a laminated state. Thereafter, the upper and lower portions of the laminator were evacuated and preheated at 110 ° C. or 150 ° C. for 5 minutes. Next, the upper part was returned to atmospheric pressure and pressed for 15 minutes to obtain a sample for measuring peel strength. In each of the obtained peel strength measurement sample (preheating temperature 110 ° C.) and peel strength measurement sample (preheating temperature 150 ° C.), the evaluation sheet was peeled off from the portion not adhered to the ethylene / vinyl acetate resin film. The peel strength was measured. In this measurement, a tensile tester “Autograph AG2000” manufactured by Shimadzu Corporation was used, and the tensile speed was 100 mm / min. From the peel strength obtained, the adhesiveness was determined according to the following criteria.
“3”: The peel strength was 25 N or more.
“2”: The peel strength was 15 N or more and less than 25 N.
“1”: The peel strength was less than 15N.

1-3. Cooling cycle test The laminated sheet was cut into a square (230 mm × 230 mm, thickness is listed in the table), and further, as shown in FIG. 15, a cut (length 100 mm) was formed in the center.
Next, on a 230 mm × 230 mm × 3 mm glass plate, two 230 mm × 230 mm × 400 μm ethylene / vinyl acetate resin films (trade name “Ultra Pearl”, manufactured by Sanvik) and the above laminated sheet , Superimposed (see FIG. 16). The laminated sheet was disposed so that the surface of the layer (A) faced the ethylene / vinyl acetate resin film. Thereafter, this laminate was put in a laminator, and the upper and lower portions were put in a vacuum state and heated at 150 ° C. for 5 minutes. Next, the upper part was returned to the atmospheric pressure and integrated by pressing for 15 minutes. This integrated product was used as a test specimen for evaluation and subjected to a thermal cycle test.
The thermal cycle test was conducted in a thermal shock chamber “TSA-101S-W” (model name) manufactured by Espec. Specifically, the test specimen for evaluation was repeatedly exposed to high temperature (100 ° C. for 30 minutes) and low temperature (−40 ° C. for 30 minutes) alternately (200 times), and the cut portion in the laminated sheet The state of occurrence of tearing was visually observed.
“3”: no tearing occurred.
“2”: The length of the tear was less than 1 mm.
“1”: The length of the tear was 1 mm or more.

1-4. Impact strength After laminating a laminated sheet (thickness is given in the table) to obtain a test piece having a size of 100 mm (MD) × 100 mm (TD), the surface of the layer (A) in the test piece is as follows. The impact strength was measured using a film impact tester manufactured by Yasuda Seiki Co., Ltd. Using a pendulum equipped with a hemispherical impact ball (diameter: 6.25 ± 0.1 mmR) fixed to a ring having an opening diameter of 50 mm and arranged at the tip, the impact ball is placed on the layer ( The impact strength required for punching the test piece was measured by striking against the surface of A). (Capacity 3J)

1-5. Absorptivity (%) for light of wavelength 400-700nm
Using a laminated sheet (50 mm × 50 mm, thickness shown in the table) as a measurement sample, transmittance and reflectance were measured with an ultraviolet-visible near-infrared spectrophotometer “V-670” (model name) manufactured by JASCO Corporation. . That is, light was emitted to the surface of the layer (A) of the measurement sample, and the transmittance and reflectance in the wavelength range from 400 nm to 700 nm were measured every 20 nm, and the average value thereof was calculated. The absorptance was calculated by the following formula using the average value of transmittance and the average value of reflectance.
Absorptivity (%) = 100− {Transmittance (%) + Reflectance (%)}

1-6. Reflectance (%) for light with a wavelength of 800 to 1,400 nm
Using a laminated sheet (50 mm × 50 mm, thickness shown in the table) as a measurement sample, the reflectance was measured with an ultraviolet-visible near-infrared spectrophotometer “V-670” (model name) manufactured by JASCO Corporation. That is, light was emitted to the surface of the layer (A) of the measurement sample, the reflectance in the wavelength region from 800 nm to 1,400 nm was measured every 20 nm, and the average value thereof was calculated.

1-7. Photoelectric conversion efficiency improvement rate (back sheet open rate 14%)
Using a Solar Simulator “WXS-200S-20, AM1.5G” (model name) manufactured by Wacom Denso Co., Ltd. in a room adjusted to a temperature of 25 ° C. ± 2 ° C. and a humidity of 50 ± 5% RH A glass sheet having a thickness of 3 mm is disposed on the surface of the single crystal silicon cell for which the photoelectric conversion efficiency has been measured, a laminated sheet is disposed on the back surface, and the silicon cell is sandwiched between the glass and the surface of the layer (A) of the laminated sheet. A sealing resin (ethylene / vinyl acetate resin) was injected between them to seal the silicon cell, thereby producing a solar cell module. Then, in order to reduce the influence of temperature, the photoelectric conversion efficiency was measured immediately after the light irradiation. The photoelectric conversion efficiency improvement rate was calculated | required using the obtained photoelectric conversion efficiency and the photoelectric conversion efficiency of the cell single-piece | unit.
Photoelectric conversion efficiency improvement rate (%) = {(Photoelectric conversion efficiency of module with 14% backsheet open rate−Photoelectric conversion efficiency of module with backsheet open rate 0%) ÷ (Photoelectric conversion of module with backsheet open rate 0%) Efficiency)} × 100

1-8. Water vapor barrier property Under the conditions of a temperature of 40 ° C. and a humidity of 90% RH, the water vapor permeability is measured according to JIS K7129B using a water vapor permeability measuring device “PERMATRAN W3 / 31” (model name) manufactured by MOCON. did. In addition, the surface on the opposite side of the layer (A) was disposed on the water vapor side as the transmission surface.

2. 2. Raw material for producing laminated sheet 2-1. Ethylene / vinyl acetate resin (X1-1)
Ethylene / vinyl acetate resin “Novatec LV120” (trade name) manufactured by Nippon Polyethylene Co., Ltd. was used. The content of vinyl acetate units is 4%.

2-2. Ethylene / vinyl acetate resin (X1-2)
Ethylene / vinyl acetate resin “Novatec LV342” (trade name) manufactured by Nippon Polyethylene Co., Ltd. was used. The content of vinyl acetate units is 10%.

2-3. Ethylene / vinyl acetate resin (X1-3)
Ethylene / vinyl acetate resin “Novatec LV430” (trade name) manufactured by Nippon Polyethylene Co., Ltd. was used. The content of vinyl acetate units is 15%.

2-4. Ethylene / vinyl acetate resin (X1-4)
Ethylene / vinyl acetate resin “NUC3461” (trade name) manufactured by Nippon Unicar Co., Ltd. was used. The content of vinyl acetate units is 20%.

2-5. Ethylene / vinyl acetate resin (X1-5)
Ethylene / vinyl acetate resin “NUC3269” (trade name) manufactured by Nippon Unicar Co., Ltd. was used. The content of vinyl acetate units is 28%.

2-6. Polyethylene resin (X2)
A polyethylene resin “Novatec LC525” (trade name) manufactured by Nippon Polyethylene Co., Ltd. was used.

2-7. Rubber reinforced resin (X3)
“Metablene SX-006” (trade name) manufactured by Mitsubishi Rayon Co., Ltd. was used. This product is a silicone / acrylic composite rubber reinforced styrene resin obtained by grafting acrylonitrile / styrene copolymer onto a silicone / acrylic composite rubber. The silicone / acrylic composite rubber content is 50% and the graft ratio is The resin is 80% and has an intrinsic viscosity [η] (in methyl ethyl ketone, 30 ° C.) of 0.38 dl / g.

2-8. Acrylonitrile styrene resin (X4)
AS resin “SAN-H” (trade name) manufactured by Techno Polymer Co., Ltd. was used.

2-9. Maleimide resin (X5)
An acrylonitrile / styrene / N-phenylmaleimide copolymer “Polyimilex PAS1460” (trade name) manufactured by Nippon Shokubai Co., Ltd. was used. This product is a resin having a content of N-phenylmaleimide units of 40% and a content of styrene units of 51%, and the Mw in terms of polystyrene by GPC is 120,000.

2-10. Infrared transmitting colorant A perylene-based black pigment “Lumogen BLACK FK4280” (trade name) manufactured by BASF was used.

2-11. Yellow colorant A quinophthalone yellow pigment “Pariotol Yellow K0961HD” (trade name) manufactured by BASF Corporation was used.

2-12. White colorant Titanium oxide “Taipeku CR-60-2” (trade name) manufactured by Ishihara Sangyo Co., Ltd. was used. The average primary particle size is 0.21 μm.

2-13. Preparation of Resin Composition for Forming Layer (A) Compositions (I-1) to (I-7) obtained by the following production examples were used.

Production Example 1-1
Ethylene / vinyl acetate resin (X1-1), infrared transmitting colorant (Y1), and yellow colorant (Y2) were added to the Henschel mixer in the proportions shown in Table 1 and mixed. Thereafter, it was melt kneaded at a barrel temperature of 160 ° C. using a twin screw extruder “TEX44” (model name) manufactured by Nippon Steel, Ltd. to obtain a resin composition (I-1) for forming a pellet-like layer (A). (See Table 1).

Production Examples 1-2 to 1-5
For forming the pellet-shaped layer (A) in the same manner as in Production Example 1-1 except that the ethylene / vinyl acetate resin (X1-1) was replaced by the type of ethylene / vinyl acetate resin shown in Table 1. Resin compositions (I-2) to (I-5) were obtained (see Table 1).

Production Example 1-6
A pellet-shaped layer (A) forming resin composition (I--) was prepared in the same manner as in Production Example 1-1 except that polyethylene resin (X2) was used in place of ethylene / vinyl acetate resin (X1-1). 6) was obtained (see Table 1).

Production Example 1-7
Instead of ethylene / vinyl acetate resin (X1-1), rubber reinforced resin (X3), acrylonitrile / styrene resin (X4) and maleimide resin (X5) were used in the proportions shown in Table 1, with a barrel temperature of 240 ° C. Except for the above, a pellet-shaped layer (A) -forming resin composition (I-7) was obtained in the same manner as in Production Example 1-1 (see Table 1).

2-14. Preparation of Resin Composition for Forming Layer (B) Compositions (II-1) to (II-7) obtained by the following production examples were used.

Production Example 2-1
Ethylene / vinyl acetate resin (X1-1) and white colorant (Y3) were added to the Henschel mixer in the proportions shown in Table 2 and mixed. Thereafter, it was melt kneaded at a barrel temperature of 160 ° C. using a twin screw extruder “TEX44” (model name) manufactured by Nippon Steel, Ltd. to obtain a pellet-shaped layer (B) forming resin composition (II-1). (See Table 2).

Production Examples 2-2 to 2-5
For forming the pellet-shaped layer (B) in the same manner as in Production Example 2-1, except that the ethylene / vinyl acetate resin of the type shown in Table 2 was used instead of the ethylene / vinyl acetate resin (X1-1). Resin compositions (II-2) to (II-5) were obtained (see Table 2).

Production Example 2-6
Resin composition for forming a pellet-like layer (B) (II-) in the same manner as in Production Example 2-1, except that polyethylene resin (X2) was used instead of ethylene / vinyl acetate resin (X1-1) 6) was obtained (see Table 2).

Production Example 2-7
Instead of ethylene / vinyl acetate resin (X1-1), rubber reinforced resin (X3), acrylonitrile / styrene resin (X4) and maleimide resin (X5) were used in the proportions shown in Table 2, and the barrel temperature was 240 ° C. Except for the above, a pellet-form resin composition (II-7) for forming a layer (B) was obtained in the same manner as in Production Example 2-1 (see Table 2).

Using the resin composition for forming the layer (B) obtained above, a film having a thickness of 100 μm was prepared, and the L value of the surface was measured.

2-15. Layer (C) forming film (W1)
A PET film “Teijin Tetron Film VW” (trade name) manufactured by Teijin DuPont was used. The thickness is 50 μm. This film is a laminated film comprising a translucent PET layer having a thickness of 35 μm and a white PET layer having a thickness of 15 μm. The L value on the surface of the translucent PET layer is 88, and the L value on the surface of the white PET layer is The value is 89.

2-16. Layer (C) forming film (W2)
A PET film “Teijin Tetron Film VW” (trade name) manufactured by Teijin DuPont was used. The thickness is 125 μm. This film is a laminated film comprising a translucent PET layer having a thickness of 100 μm and a white PET layer having a thickness of 25 μm. The L value on the surface of the translucent PET layer is 88, and L on the surface of the white PET layer. The value is 89.

2-17. Layer (C) forming film (W3)
A white highly concealed PET film “Lumirror E20” (trade name) manufactured by Toray Industries, Inc. was used. The thickness is 100 μm. The L value on the film surface is 91.

2-18. Layer (C) forming film (W4)
A translucent PET film “Lumirror X10S” (trade name) manufactured by Toray Industries, Inc. was used. The thickness is 50 μm. The L value on the film surface is 59.

2-19. Water vapor barrier layer (D) forming film (S1)
A transparent vapor deposition film “Tech Barrier LX” (trade name) manufactured by Mitsubishi Plastics, Inc. was used. It is a transparent film having a silica vapor deposition film on one side of a PET film, and has a thickness of 12 μm and a water vapor transmission rate (JIS K7129) of 0.2 g / (m ² · day).

2-20. Water vapor barrier layer (D) forming film (S2)
An inorganic binary vapor barrier film “Ecosia VE500” (trade name) manufactured by Toyobo Co., Ltd. was used. It is a transparent film obtained by vapor-depositing (silica / alumina) on one side of a PET film, and has a thickness of 12 μm and a water vapor permeability of 0.5 g / (m ² · day).

3. Production and Evaluation of Laminated Sheet of First Embodiment Example 1-1
A multilayer film molding machine having a T-die having a die width of 1,400 mm and a lip interval of 1.5 mm and having two extruders with a screw diameter of 65 mm is used. In each extruder, a resin composition for forming a layer (A) ( I-1) and the resin composition (II-1) for forming the layer (B) were supplied. And each resin composition fuse | melted at the temperature of 135 degreeC was discharged from the T-die, and it was set as the 2 layer type soft film. Thereafter, the two-layer soft film was brought into surface contact with a cast roll whose surface temperature was controlled at 40 ° C. with an air knife, cooled and solidified to obtain a coextruded film. The thicknesses of the layer (A) and the layer (B) are as shown in Table 3. Thickness gauge “ID-C1112C” (model name) manufactured by Mitutoyo Co., Ltd. was used to cut the film after 1 hour from the start of film production. Then, the thickness was measured at intervals of 10 mm (n = 107), and the average value was obtained. Measurement point values in the range of 20 mm from the edge of the film were removed from the average calculation.
Next, the surface of the layer (B) in the coextruded film and the surface of the translucent PET layer of the layer (C) forming film (W1) are adhered using a polyurethane-based adhesive, and the layer (A ), A layer (B), and a layered sheet having a three-layer structure composed of a layer (C) in which two layers containing a saturated polyester resin are continuous were obtained (see FIG. 2). The thickness is 210 μm. And about this laminated sheet, various evaluation was performed and the result was written together in Table 3.

Examples 1-2 to 1-4
Instead of the layer (A) forming resin composition (I-1) and the layer (B) forming resin composition (II-1), the types of layers (A) forming resin compositions shown in Table 3 respectively. The layer (A), the layer (B), and two layers containing a saturated polyester resin were successively formed in the same manner as in Example 1-1 except that the resin composition for forming the layer (B) was used. A laminated sheet having a three-layer structure composed of the layers (C) was obtained (see FIG. 2). The thickness is 210 μm. Various evaluations were performed on the laminated sheet, and the results are also shown in Table 3.

Example 1-5
Instead of the layer (A) forming resin composition (I-1) and the layer (B) forming resin composition (II-1), the layer (A) forming resin composition (I-3) and Example 1 except that the layer (B) -forming resin composition (II-3) was used and the layer (C) -forming film (W2) was used instead of the layer (C) -forming film (W1). In the same manner as in Example 1, a laminated sheet having a three-layer structure including a layer (A), a layer (B), and a layer (C) in which two layers containing a saturated polyester resin are continuous is obtained (FIG. 2). reference). The thickness is 285 μm. Various evaluations were performed on the laminated sheet, and the results are also shown in Table 3.

Example 1-6
In the same manner as in Example 1-1, except that the layer (A) forming resin composition (I-3) was used instead of the layer (A) forming resin composition (I-1), the layer ( A laminated sheet having a three-layer structure comprising A), a layer (B), and a layer (C) in which two layers containing a saturated polyester resin were continuous was obtained (see FIG. 2). The thickness is 210 μm. Various evaluations were performed on the laminated sheet, and the results are also shown in Table 3.

Example 1-7
Instead of the layer (A) forming resin composition (I-1) and the layer (B) forming resin composition (II-1), the layer (A) forming resin composition (I-3) and Example 1 except that the layer (B) forming resin composition (II-3) was used and the layer (C) forming film (W3) was used instead of the layer (C) forming film (W1). In the same manner as in Example 1, a laminated sheet having a three-layer structure including a layer (A), a layer (B), and a layer (C) was obtained (see FIG. 1). The thickness is 260 μm. Various evaluations were performed on the laminated sheet, and the results are also shown in Table 3.

Example 1-8
Instead of the layer (A) forming resin composition (I-1) and the layer (B) forming resin composition (II-1), the layer (A) forming resin composition (I-3) and Using the resin composition (II-3) for forming the layer (B), a coextruded film was obtained in the same manner as in Example 1-1. Thereafter, the layer (C) forming film (W3) is adhered to the surface of the layer (B) in the coextruded film using a polyurethane-based adhesive, and then the layer (C) forming film in the laminated film. The surface of the translucent PET layer of the layer (C) forming film (W1) is adhered to the (W3) side surface using a polyurethane-based adhesive, and the layer (A), the layer (B), and A laminated sheet having a three-layer structure composed of a layer (C) in which three layers containing a saturated polyester resin are continuous was obtained (see FIG. 3). The thickness is 310 μm. Various evaluations were performed on the laminated sheet, and the results are also shown in Table 3.

Example 1-9
Instead of the layer (A) forming resin composition (I-1) and the layer (B) forming resin composition (II-1), the layer (A) forming resin composition (I-3) and Example 1 except that the layer (B) forming resin composition (II-3) was used, and the layer (C) forming film (W4) was used instead of the layer (C) forming film (W1). In the same manner as in Example 1, a laminated sheet having a three-layer structure including a layer (A), a layer (B), and a layer (C) was obtained (see FIG. 1). The thickness is 210 μm. Various evaluations were performed on the laminated sheet, and the results are also shown in Table 3.

Comparative Example 1-1
Instead of the layer (A) forming resin composition (I-1) and the layer (B) forming resin composition (II-1), respectively, the layer (A) forming resin composition (I-5) and A laminated sheet was obtained in the same manner as in Example 1-1 except that the resin composition (II-5) for forming the layer (B) was used. Various evaluations were performed on the laminated sheet, and the results are also shown in Table 4.

Comparative Example 1-2
Instead of the layer (A) forming resin composition (I-1) and the layer (B) forming resin composition (II-1), the layer (A) forming resin composition (I-6) and A laminated sheet was obtained in the same manner as in Example 1-1 except that the resin composition (II-6) for forming the layer (B) was used. Various evaluations were performed on the laminated sheet, and the results are also shown in Table 4.

Comparative Example 1-3
Instead of the layer (A) forming resin composition (I-1) and the layer (B) forming resin composition (II-1), the layer (A) forming resin composition (I-7) and A laminated sheet was obtained in the same manner as in Example 1-1 except that the resin composition (II-7) for forming the layer (B) was used. Various evaluations were performed on the laminated sheet, and the results are also shown in Table 4.

4). Production and Evaluation of Laminated Sheet of Second Embodiment Example 2-1
A multilayer film molding machine having a T-die having a die width of 1,400 mm and a lip interval of 1.5 mm and having two extruders with a screw diameter of 65 mm is used. In each extruder, a resin composition for forming a layer (A) ( I-1) and the resin composition (II-1) for forming the layer (B) were supplied. And each resin composition fuse | melted at the temperature of 135 degreeC was discharged from the T-die, and it was set as the 2 layer type soft film. Thereafter, the two-layer soft film was brought into surface contact with a cast roll whose surface temperature was controlled at 40 ° C. with an air knife, cooled and solidified to obtain a coextruded film. The thicknesses of the layer (A) and the layer (B) are as shown in Table 5. Thickness gauge “ID-C1112C” (model name) manufactured by Mitutoyo Co., Ltd. was used to cut the film after 1 hour from the start of film production. Then, the thickness was measured at intervals of 10 mm (n = 107), and the average value was obtained. Measurement point values in the range of 20 mm from the edge of the film were removed from the average calculation.
Next, the water vapor barrier layer (D) forming film (S1) is bonded to the surface of the layer (B) in the coextruded film with a polyurethane adhesive so that the vapor deposition film becomes the outer surface. I let you. Further, the layer (C) forming film (W1) is adhered to the surface of the vapor deposition film in the water vapor barrier layer (D) by using a polyurethane-based adhesive so that the white PET layer becomes the outer surface, A laminated sheet having a four-layer structure comprising a layer (A), a layer (B), a water vapor barrier layer (D), and a layer (C) in which two layers containing a saturated polyester resin are continuous was obtained (FIG. 8). reference). The thickness is 222 μm. And about this laminated sheet, various evaluation was performed and the result was written together in Table 5.

Examples 2-2 to 2-4
Instead of the layer (A) forming resin composition (I-1) and the layer (B) forming resin composition (II-1), the types of layers (A) forming resin compositions shown in Table 5 respectively. The layer (A), the layer (B), the water vapor barrier layer (D), and the saturated polyester resin are contained in the same manner as in Example 2-1, except that the resin composition for forming the layer (B) is used. A laminated sheet having a four-layer structure composed of two consecutive layers (C) was obtained (see FIG. 8). The thickness is 222 μm. And about this laminated sheet, various evaluation was performed and the result was written together in Table 5.

Example 2-5
Instead of the layer (A) forming resin composition (I-1) and the layer (B) forming resin composition (II-1), the layer (A) forming resin composition (I-3) and Example 2 except that the layer (B) forming resin composition (II-3) was used and the layer (C) forming film (W2) was used instead of the layer (C) forming film (W1). In the same manner as in -1, a four-layer structure comprising a layer (A), a layer (B), a water vapor barrier layer (D), and a layer (C) in which two layers containing a saturated polyester resin are continuous A sheet was obtained (see FIG. 8). The thickness is 297 μm. And about this laminated sheet, various evaluation was performed and the result was written together in Table 5.

Example 2-6
In the same manner as in Example 2-1, except that the layer (A) forming resin composition (I-3) was used instead of the layer (A) forming resin composition (I-1), a layer ( A laminated sheet having a four-layer structure comprising A), a layer (B), a water vapor barrier layer (D), and a layer (C) in which two layers containing a saturated polyester resin are continuous was obtained (see FIG. 8). . The thickness is 222 μm. And about this laminated sheet, various evaluation was performed and the result was written together in Table 5.

Example 2-7
Instead of the layer (A) forming resin composition (I-1) and the layer (B) forming resin composition (II-1), the layer (A) forming resin composition (I-3) and Example 2 except that the layer (B) forming resin composition (II-3) was used and the layer (C) forming film (W3) was used instead of the layer (C) forming film (W1). In the same manner as in Example 1, a laminated sheet having a four-layer structure including a layer (A), a layer (B), a water vapor barrier layer (D), and a layer (C) was obtained (see FIG. 7). The thickness is 272 μm. And about this laminated sheet, various evaluation was performed and the result was written together in Table 5.

Example 2-8
Instead of the layer (A) forming resin composition (I-1) and the layer (B) forming resin composition (II-1), the layer (A) forming resin composition (I-3) and A coextruded film was obtained in the same manner as in Example 2-1, using the resin composition (II-3) for forming the layer (B). Thereafter, the layer (C) forming film (W3) was adhered to the surface of the layer (B) in the coextruded film using a polyurethane-based adhesive. Next, on the surface of the layer (C) forming film (W3) in this adhesive film, the water vapor barrier layer (D) forming film (S1) is deposited on the outer surface so that the vapor deposition film becomes the outer surface. It was made to adhere using. Further, the layer (C) forming film (W1) is adhered to the surface of the vapor deposition film in the water vapor barrier layer (D) by using a polyurethane-based adhesive so that the white PET layer becomes the outer surface, A laminated sheet having a five-layer structure comprising a layer (A), a layer (B), a layer (C), a water vapor barrier layer (D), and a layer (C) in which two layers containing a saturated polyester resin are continuous. Obtained (not shown). The thickness is 322 μm. And about this laminated sheet, various evaluation was performed and the result was written together in Table 5.

Example 2-9
Instead of the layer (A) forming resin composition (I-1) and the layer (B) forming resin composition (II-1), the layer (A) forming resin composition (I-3) and Example 2 except that the layer (B) forming resin composition (II-3) was used and the layer (C) forming film (W4) was used instead of the layer (C) forming film (W1). In the same manner as in Example 1, a laminated sheet having a four-layer structure including a layer (A), a layer (B), a water vapor barrier layer (D), and a layer (C) was obtained (see FIG. 7). The thickness is 222 μm. And about this laminated sheet, various evaluation was performed and the result was written together in Table 5.

Example 2-10
Instead of the layer (A) forming resin composition (I-1) and the layer (B) forming resin composition (II-1), the layer (A) forming resin composition (I-3) and The layer (B) forming resin composition (II-3) was used, except that the water vapor barrier layer (D) forming film (S2) was used instead of the water vapor barrier layer (D) forming film (S1). In the same manner as in Example 2-1, a layer (A), a layer (B), a water vapor barrier layer (D), and a layer (C) in which two layers containing a saturated polyester resin are continuous 4 A laminated sheet having a layer structure was obtained (see FIG. 8). The thickness is 222 μm. And about this laminated sheet, various evaluation was performed and the result was written together in Table 5.

Comparative Example 2-1
Instead of the layer (A) forming resin composition (I-1) and the layer (B) forming resin composition (II-1), the layer (A) forming resin composition (I-5) and A laminated sheet was obtained in the same manner as in Example 2-1, except that the resin composition (II-5) for forming the layer (B) was used. Various evaluations were performed on the laminated sheet, and the results are also shown in Table 6.

Comparative Example 2-2
Instead of the layer (A) forming resin composition (I-1) and the layer (B) forming resin composition (II-1), the layer (A) forming resin composition (I-6) and A laminated sheet was obtained in the same manner as in Example 2-1, except that the resin composition (II-6) for forming the layer (B) was used. Various evaluations were performed on the laminated sheet, and the results are also shown in Table 6.

Comparative Example 2-3
Instead of the layer (A) forming resin composition (I-1) and the layer (B) forming resin composition (II-1), the layer (A) forming resin composition (I-7) and A laminated sheet was obtained in the same manner as in Example 2-1, except that the resin composition (II-7) for forming the layer (B) was used. Various evaluations were performed on the laminated sheet, and the results are also shown in Table 6.

In the laminated sheet according to the first aspect of the present invention, when light is emitted to the surface of the layer (A), infrared rays are easily transmitted through the layer (A), so that heat storage in the layer (A) is suppressed. When the layer (B) is a white layer, the light transmitted through the layer (A) is excellent in reflectivity in the layer (B), so that heat storage in the layer (B) is also suppressed. And it is excellent in weather resistance without causing deterioration due to light reception, etc., is less likely to cause defects such as tearing due to a cold cycle environment, has excellent heat resistance and strength, and can maintain design and shape over a long period of time. it can. Furthermore, the adhesion between the surface of the layer (A) and the counterpart material is extremely excellent. Therefore, it is suitable for an application in which long-term exposure to sunlight and shape stability and the like are required over a long period of time. Especially, it is useful as a structural member of the solar cell module which comprises the solar cell arrange | positioned on roofs, such as a house and a building, ie, a solar cell backsheet. Since this laminated sheet is excellent in flexibility, it is not dependent on the shape of the solar cell module, that is, it is arranged according to the surface shape of the filler portion filling the gaps of the solar cell elements included in the solar cell module. It is suitable for protecting solar cell elements.

Further, in the laminated sheet of the second aspect of the present invention, when light is radiated to the surface of the layer (A), infrared rays are easily transmitted through the layer (A), so that heat storage in the layer (A) is suppressed. The Since the layer (B) is a white layer, the light transmitted through the layer (A) is excellent in reflectivity in the layer (B), and heat storage in the layer (B) is also suppressed. And it is excellent in weather resistance without causing deterioration due to light reception, etc., is less likely to cause defects such as tearing due to a cold cycle environment, has excellent heat resistance and strength, and can maintain design and shape over a long period of time. it can. Moreover, it is excellent in the adhesiveness of the surface of a layer (A) and a counterpart material, and is excellent in the water vapor barrier property from the one surface side to the other surface side. Therefore, it is suitable for an application in which long-term exposure to sunlight and shape stability and the like are required over a long period of time. Especially, it is useful as a structural member of the solar cell module which comprises the solar cell arrange | positioned on roofs, such as a house and a building, ie, a solar cell backsheet. Since this laminated sheet is excellent in flexibility, it is not dependent on the shape of the solar cell module, that is, it is arranged according to the surface shape of the filler portion filling the gaps of the solar cell elements included in the solar cell module. It is suitable for protecting solar cell elements.

1: Laminated sheet 11: Layer (A)
12: Layer (B)
13, 13a and 13b: Layer (C)
14, 14a and 14b: Water vapor barrier layer (D)
15: Other layer 2: Solar cell module 21: Front side transparent protective member 23: Front side sealing film 25: Solar cell element 27: Back side sealing film 3: Notch 5: Ethylene / vinyl acetate resin film 7: Glass Board

Claims

A layer (A) containing an ethylene / vinyl acetate resin having a vinyl acetate unit content of 2 to 25% by mass and an infrared transmitting colorant;
A layer (B) containing an ethylene-vinyl acetate resin and a white colorant;
A layer (C) containing a saturated polyester resin;
Are sequentially provided.
The laminate sheet according to claim 1, wherein the content of vinyl acetate units constituting the ethylene / vinyl acetate resin in the layer (A) is more than 8% by mass and 25% by mass or less.
The laminated sheet according to claim 1 or 2, wherein the layer (C) comprises at least one layer selected from a white layer containing a white colorant, a transparent layer and a translucent layer.
The laminated sheet according to any one of claims 1 to 3, further comprising a water vapor barrier layer (D) as an intermediate layer.
The laminate sheet according to claim 4, wherein the water vapor barrier layer (D) is provided between the layer (B) and the layer (C).
The laminated sheet according to claim 4, wherein the water vapor barrier layer (D) is provided between the plurality of layers (C).
The laminated sheet according to any one of claims 4 to 6, wherein the water vapor barrier layer (D) comprises a vapor-deposited film in which a film containing a metal and / or a metal oxide is formed on the surface of the resin layer.
The laminated sheet according to any one of claims 1 to 7, wherein when light having a wavelength of 400 to 700 nm is radiated to the surface of the layer (A) in the laminated sheet, the light absorptance is 60% or more. .
9. The light according to any one of claims 1 to 8, wherein when light having a wavelength of 800 to 1,400 nm is radiated to the surface of the layer (A) in the laminated sheet, the reflectance with respect to the light is 50% or more. Laminated sheet.
The laminated sheet according to any one of claims 1 to 9, wherein the thickness is 30 to 900 µm.
A solar cell module comprising the laminated sheet according to any one of claims 1 to 10.