JP5194718B2 - Laminated body - Google Patents

Description

  The present invention relates to a laminate, and more specifically, it has good adhesion to a filler comprising a solar cell module, in particular, an ethylene-vinyl acetate copolymer, and weather resistance, water resistance, The present invention relates to a laminate useful for an inexpensive solar cell back surface protective sheet excellent in various properties such as moisture resistance and flame retardancy.

  In recent years, various efforts have been made to control the emission of carbon dioxide, with increasing interest in global warming. Increasing fossil fuel consumption leads to an increase in atmospheric carbon dioxide, and the greenhouse effect raises the Earth's temperature, significantly affecting the global environment. Various studies have been carried out to solve this global problem, and in particular, solar power generation is highly expected in terms of cleanliness and non-pollution. Solar cells constitute the heart of a photovoltaic power generation system that directly converts sunlight energy into electricity, and are made of single crystal, polycrystalline, or amorphous silicon semiconductors. As a structure, a solar cell element (cell) is not used as it is, and a surface to which sunlight is applied is generally covered with a glass surface, and a thermoplastic (especially ethylene-vinyl acetate copolymer) is covered. The gap is filled with a filler composed of the above, and the back surface is protected by a sealing sheet.

  Conventionally, for example, as a back surface protection sheet for solar cells, a back surface protection sheet having a laminated structure in which an aluminum foil is sandwiched between polyvinyl fluoride films (DuPont Co., Ltd., trade name: Tedlar) has been often used.

  However, when using a composite film of a fluorine resin film such as the above-mentioned polyvinyl fluoride film and a metal foil such as an aluminum foil as the back surface protection sheet layer constituting the solar cell module, this polyvinyl fluoride film is A polyvinyl fluoride film on the inner surface that is softened by heat of a hot press at 140 ° C. to 150 ° C. applied during the manufacture of the solar cell module, the protrusions of the solar cell element electrode portion penetrate the filler layer, and further constitutes a back surface protection sheet And the solar cell element and the aluminum foil are short-circuited to adversely affect the battery performance. At the same time, the use of aluminum foil has been regarded as a problem in terms of disposal.

  Therefore, without using a metal foil such as an aluminum foil, by using a back surface protective sheet provided with a vapor deposition layer made of an inorganic compound on a base film such as a fluororesin film or a polyester film, the battery performance is short-circuited. It has become possible to eliminate disadvantages such as adverse effects (see, for example, Patent Document 1: Japanese Patent Laid-Open No. 2002-134771).

However, if the fluorine resin film is left as it is, the adhesion with the inorganic compound is bad, and therefore it is necessary to perform a pretreatment such as plasma treatment on the fluorine resin film, so that there is a problem that the film surface is removed and the barrier property is deteriorated. There is. Moreover, in the case of a polyester film, there exists a problem that there is no flame retardance compared with a fluorine resin film.
JP 2002-134771 A

  The object of the present invention is to have a good adhesion with a filler comprising an ethylene-vinyl acetate copolymer, particularly constituting a solar cell module, and excellent in various properties such as weather resistance, water resistance, moisture resistance, It is providing the laminated body useful for the cheap back surface protection sheet for solar cells excellent also in the flame retardance. Moreover, it is providing the back surface protection sheet for solar cells using the said laminated body.

The invention described in claim 1
A laminate in which an organic compound layer and an inorganic compound layer are sequentially provided on at least one surface of a fluorine resin film,
The organic compound layer is at least
Formed on said fluorine-based resin film, including the including organic compound layer A fluorine compound having an addition-polymerizable functional group, the molecular weight has a trialkoxysilyl group 150 to 600 and (meth) acrylic compound, and An organic compound layer B formed on the side in contact with the inorganic compound layer,
Curing the organic compound layer A and the organic compound layer B by active energy ray irradiation or plasma irradiation,
The organic compound layer and the inorganic compound layer before curing are formed by using a vapor deposition method in a vacuum atmosphere.

According to a second aspect of the present invention, the organic compound layer A and the organic compound layer B before curing are sequentially deposited on the fluororesin film in a vacuum atmosphere, and then aggregated and irradiated with active energy rays or plasma. The laminate according to claim 1, wherein the laminate is cured at the same time.

  The invention according to claim 3 is the laminate according to claim 1 or 2, wherein the addition polymerization functional group is an acryl group or a methacryl group.

  The invention according to claim 4 is the laminate according to any one of claims 1 to 3, wherein the organic compound layer is formed using a flash vapor deposition method.

  The invention according to claim 5 is the laminate according to any one of claims 1 to 4, wherein the inorganic compound layer is formed using a chemical vapor deposition (CVD) method.

  The invention according to claim 6 is the laminate according to any one of claims 1 to 5, wherein the organic compound layer and the inorganic compound layer are formed without being exposed to the atmosphere in the same vacuum. It is.

  The invention according to claim 7 is a back protective sheet for solar cells, wherein a fluorine-based resin film is bonded to both surfaces of the laminate according to any one of claims 1 to 6 via an adhesive. It is.

  According to the present invention, the solar cell module has a good adhesion with a filler made of an ethylene-vinyl acetate copolymer, and has excellent properties such as weather resistance, water resistance, moisture resistance, A laminate useful for an inexpensive solar cell back surface protective sheet having excellent flame retardancy can be provided. Moreover, the back surface protection sheet for solar cells using the said laminated body can be provided.

  Hereinafter, a preferred embodiment of a method for producing a solar cell back surface protective sheet using the laminate of the present invention will be described with reference to the drawings. FIG. 1 is a schematic view of an apparatus that can be used for producing the laminate of the present invention, and FIG. 2 is a cross-sectional view of an example of the laminate of the present invention. FIG. 3 is a cross-sectional view of an example of a back surface protection sheet for solar cells using the laminate of the present invention.

  Hereinafter, in the organic compound layer in the present invention, the organic compound layer A before curing may be referred to as an active energy ray curable resin raw material layer A, and the organic compound layer B before curing may be referred to as an active energy ray curable resin raw material layer B. Further, the organic compound layer A and the organic compound layer B cured by active energy ray irradiation or plasma irradiation are referred to as an active energy ray curable resin layer A and an active energy ray curable resin layer B, respectively.

  In FIG. 1, a process roll (3) is installed inside a vacuum film forming apparatus (1) connected to a vacuum pump A (2), and an unwinding roll (4) and a winding roll (5) are installed on the upper part thereof. Around the process roll (3), active energy ray curable resin raw material layer A resin vapor deposition device (6), active energy ray curable resin raw material layer B resin vapor deposition device (7), electron beam irradiation device (8), inorganic compound layer A forming device (10) is installed. Furthermore, an active energy ray curable resin raw material layer A resin vapor deposition device (6) is connected to an active energy ray curable resin layer A resin raw material supply device (11), and the active energy ray curable resin raw material layer B resin vapor deposition device (7). ) Is connected to the active energy ray curable resin layer B resin material supply device (12), and the gas supply device (13) is connected to the electron beam irradiation device (8). Further, the electron beam irradiation device (8) and the inorganic compound layer forming device (10) are respectively provided with a vacuum pump B (14), a vacuum pump C (15), a pressure regulating valve A (16), and a pressure regulating valve B (17). Connecting. Further, the degree of vacuum suitable for each process can be adjusted by providing the shielding plate A (9), the shielding plate B (18), and the shielding plate C (19). Since the active energy ray curable resin layer and the inorganic compound layer can be formed in the same vacuum film forming apparatus, each film forming condition can be easily optimized, and at the same time, there is little dust contamination and high productivity. The body can be manufactured. In addition, the number of processes and lead time can be reduced.

  The raw material of the base material (101) of the fluororesin film is attached to the unwinding roll (4), and an original material conveyance path reaching the winding roll (5) through the process roll (3) is formed. The vacuum film forming apparatus (1) is evacuated by a vacuum pump A (2), a vacuum pump B (14), and a vacuum pump C (15). Here, the example of the manufacturing apparatus in which the active energy ray-curable resin layers A and B and the inorganic compound layer are sequentially laminated has been described, but the present invention is not limited thereto.

  Hereinafter, the film forming process will be described. The active energy ray-curable resin layer A (102), the active energy ray-curable resin layer B (103), and the inorganic compound layer (104) are formed on the base material (101) of the fluororesin film. The active energy ray-curable resin layers A and B are formed by sequentially forming an active energy ray-curable resin material layer by a vapor deposition method in a vacuum atmosphere, and then polymerizing the active energy ray-curable resin layers A and B by irradiation with one of electron beam, plasma, and ultraviolet rays. Compared with the polymerization method using heat, this method can perform polymerization in a short time, and has a feature that the elongation of the base material and the deformation of the hardened layer are less caused by heat load. In addition, by employing a vapor deposition method, there is no need for solvent recovery compared to gravure coating or the like, and it is environmentally friendly because it is solvent-free. Furthermore, aging time is unnecessary and advantageous.

The active energy ray curable resin layer A is laminated on a fluorine resin film substrate made of a fluorine compound, thereby improving the adhesion between the substrate and the active energy ray curable resin layer B. It is a layer that becomes a primer layer. Examples of the base material of the fluororesin film include polyvinyl fluoride, polyvinylidene fluoride, ethylene tetrafluoroethylene, and the thickness thereof is not particularly limited, but suitable as a packaging material, an organic vapor deposition layer, Considering the workability of laminating the inorganic vapor deposition layer and the coating layer, the thickness is preferably 6 to 50 μm.
The active energy ray-curable resin layer A is a layer obtained by polymerizing and curing a fluorine compound having an addition polymerization functional group. The fluorine compound has, for example, a perfluoroalkyl chain and has a vinyl group, an acrylic group, a methacryl group. And compounds having an addition polymerizable functional group containing any of the groups. As carbon number in a perfluoroalkyl group, 150-2000 are preferable.

  Strictly speaking, the fluorine compound having an addition-polymerizable functional group here is effective in addition to addition polymerization, such as condensation polymerization. However, in general, addition polymerization is performed before and after polymerization compared to other polymerizations. Volume change, especially shrinkage is small, and various adverse effects during coating and use are small and preferable. Further, compared with addition polymerization generally initiated by radicals or the like, condensation polymerization tends to have a slower curing reaction rate.

  In the fluorine compound having an addition polymerization functional group, the addition polymerization functional group is preferably an acrylic group or a methacryl group. These groups are easy to handle, have excellent polymerizability, and have sufficient film hardness. Especially when you want to suppress skin irritation during preparation or to obtain a hard film, use a methacrylic group. Conversely, when you want to obtain a soft film or to polymerize efficiently with a low energy amount, use acrylic. Adjustments can be made as appropriate, such as using a base material.

  The film thickness of the active energy ray-curable resin layer A is preferably 0.1 to 1.0 μm. If it is thinner than 0.1 μm, the surface is not smooth due to the influence of the lubricant. On the other hand, if it is thicker than 1.0 μm, poor curing tends to occur.

The active energy ray curable resin layer B is laminated between an inorganic compound layer and an active energy ray curable resin A layer by laminating under the inorganic compound layer (104) made of an inorganic compound such as silicon oxide or silicon nitride. It is a so-called primer layer that improves adhesion. The (meth) acrylic compound having a trialkoxysilyl group having a molecular weight of 150 to 600 is not particularly limited, and includes 1 trialkoxysilyl group and 1 to 3 (meth) acrylic groups in the molecule. good. When there is one (meth) acryl group, higher adhesion with the inorganic compound layer can be obtained. When the number is two or three, the film strength of the active energy ray-curable resin layer B can be increased by increasing the crosslinking density, but at the same time, the adhesion may be slightly decreased. Examples of the (meth) acrylic compound having a trialkoxysilyl group having a molecular weight of 150 to 600 include 3-acryloxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, and other silane coupling agents; A compound obtained by reacting (meth) acrylic acid can be used. In the active energy ray-curable resin layer B, a monofunctional (meth) acrylate or a bifunctional or higher (meth) acrylic compound can be blended depending on purposes such as strength, flexibility, and scratch resistance. It is not specifically limited, For example, the compound which has hydroxyl groups, such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, Compounds having an amino group such as diethylaminoethyl (meth) acrylate, carboxyl groups such as (meth) acrylic acid, 2- (meth) acryloyloxyethyl succinic acid, 2- (meth) acryloyloxyethyl hexahydrophthalic acid (Meth) acrylate having a cyclic skeleton such as a compound, glycidyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, cyclohexyl (meth) acrylate, phenoxyethyl (meth) acrylate, isobornyl (meth) acrylate, etc. Rate, isoamyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, butoxyethyl (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, methoxytriethylene glycol (meth) acrylate, methoxydipropylene glycol (meth) Acrylic monofunctional compounds such as acrylate, diethylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) Acrylate, triethylene di (meth) acrylate, PEG # 200 di (meth) acrylate, PEG # 400 di (meth) acrylate, PEG # 600 di (meth) acrylate, neopentyl Bifunctional (meth) acrylic compounds such as (meth) acrylate, dimethylol tricyclodecane di (meth) acrylate, etc., bifunctional epoxy (meth) acrylate, bifunctional urethane (meth) acrylate, etc. A functional (meth) acryl compound is mentioned. Further, as compounds having three or more (meth) acryl groups, dipentaerythritol hexa (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, trimethylolpropane triacrylate, trimethylol An acrylic polyfunctional monomer such as propanetetraacrylate, (meth) acryl polyfunctional epoxy acrylate, (meth) acryl polyfunctional urethane acrylate, and the like can be used.

When the active energy ray-curable resin layer B contains a trialkoxysilyl group having a molecular weight of 150 to 600, for example, it binds to Si, so that the adhesion with the inorganic compound layer is improved. If the molecular weight of the trialkoxysilyl group is less than 150, it is difficult to form a film, and the film strength is weak. If the molecular weight is more than 600, the evaporation temperature is high, and thermal polymerization is likely to occur at a high temperature.
The film thickness of the active energy ray-curable resin layer B is preferably 0.05 to 0.3 μm. If it is thinner than 0.05 μm, the surface is not smooth due to the influence of the lubricant. Also, it is thin and difficult to form a film. If it is thicker than 0.3 μm, curing failure tends to occur.

The active energy ray-curable resin layers A and B are preferably formed by forming the active energy ray-curable resin raw material layers A and B, then aggregating them, and then simultaneously irradiating them with active energy rays or plasma. According to this embodiment, the active energy ray-curable resin layers A and B are appropriately mixed at the interface, peeling at the interface is suppressed, and adhesion can be improved.
In addition, it can superpose | polymerize in a short time by irradiating an active energy ray or a plasma, and there exists an effect that there is little deformation | transformation of the base material extension and organic compound layer by heat addition.

  The active energy ray curable resin raw material layers A and B are preferably formed using a flash vapor deposition method. According to this form, the material can be instantly vaporized and agglomerated on the base material; the film thickness can be made very thin; it is solvent-free and good for the environment; Since it is performed in a vacuum, there are effects such as a clean film.

  Furthermore, an inorganic compound layer (104) is provided on the surface of the active energy ray-curable resin layer B. The inorganic compound layer (104) can be formed by, for example, a chemical vapor deposition (CVD) method. The chemical vapor deposition (CVD) method is preferable because a dense and thin film can be formed, and the deposited film does not break and the barrier performance does not deteriorate with respect to the bending and elongation of the film.

The inorganic compound layer (104) was formed of any one of a silicon oxide film, a silicon nitride film, and a silicon oxynitride film, and was activated by plasma using an organic silane material such as hexamethyldisiloxane (HMDSO) as a raw material. Formed by reaction with oxygen and nitrogen under atmosphere.
The amount of the source gas and the reaction gas to be supplied is optimized depending on the film thickness, the degree of oxidation, the winding speed, the size of the vacuum film forming apparatus (1), and the like. The film formation process of the inorganic compound layer (104) is not limited to the chemical vapor deposition (CVD) method, and may be formed by sputtering a target such as silicon oxide, silicon nitride, or silicon. You may form by a vacuum evaporation method.
The film thickness of the inorganic compound layer (104) is preferably 5 to 300 nm. If the thickness is less than 5 nm, a uniform film cannot be obtained, and the film thickness is not sufficient for exhibiting the barrier function. If the thickness is more than 300 nm, the film tends to be flexible and easily cracked due to external stress.

A polymerization initiator can be blended with each of the active energy ray-curable resin layers A and B in order to allow the polymerization to proceed efficiently. The polymerization initiator is not particularly limited as long as it is a compound that generates radicals when irradiated with active energy. For example, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2-methyl [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2,2- Dimethoxy-1,2-diphenylethane-1-one, benzophenone, 1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methyl 1-propan-1-one, 2-benzyl-2-dimethylamino-1 -(4-Morpholinophenyl) butan-1-one, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide and the like can be used. In this invention, the compounding quantity of a polymerization initiator is 0.1-10 weight part with respect to 100 weight part of active energy ray hardening resin layers A and B, Preferably it is 1-7 weight part, More preferably, it is 1-5 weight part. Is done.

  The active energy ray curable resin layer may be formed by laminating A and B, respectively, but the active energy ray curable resin is placed between the active energy ray curable resin layers A and B depending on purposes such as flexibility and impact resistance. Layer C can be provided. The active energy ray-curable resin layer C is not particularly limited as long as it is a (meth) acrylic compound capable of obtaining desired characteristics.

The laminated body as a back surface protection sheet for solar cells is shown in FIG.
The back protective sheet for a solar cell is provided with a coating layer (105) on the surface of the inorganic compound layer (104) of the laminate of FIG. 2, and the front and back surfaces are coated with a fluorine-based adhesive by using a dry lamination method (106, 107). A resin film (108, 109) is bonded.

  The coating layer (105) is for protecting the inorganic compound layer (104) and is a layer for imparting higher gas barrier properties.

  With respect to the coating layer (105), examples of the material for forming the coating layer that imparts high gas barrier properties include a water-soluble polymer, one or more metal alkoxides and / or hydrolysates thereof, and the metal The alkoxide is formed by coating a solution composed of tetraethoxysilane, triisopropoxyaluminum, or a mixture thereof. Other examples of the coating layer that imparts high gas barrier properties include those comprising a water-soluble polymer and tin chloride, and further comprising a solution comprising the water-soluble polymer coated with polyvinyl alcohol. Specifically, a solution in which a water-soluble polymer and tin chloride are dissolved in an aqueous (water or water / alcohol mixed) solvent, or a solution in which a metal alkoxide is directly or previously hydrolyzed in the solution. The mixed solution is formed on the inorganic compound layer (104) by coating and drying by heating. Each component forming the coating layer (105) will be described in more detail.

  Specific examples of the water-soluble polymer used for forming the coating layer (105) include polyvinyl alcohol, polyvinyl pyrrolidone, starch, methyl cellulose, carboxymethyl cellulose, sodium alginate and the like. In particular, polyvinyl alcohol (hereinafter referred to as PVA) has the best gas barrier properties. The PVA here is generally obtained by saponifying polyvinyl acetate, and includes from so-called partially saponified PVA in which several dozen percent of acetate groups remain to complete PVA in which only several percent of acetate groups remain. There is no particular limitation.

The tin chloride may be stannous chloride (SnCl ₂ ), stannic chloride (SnCl ₄ ), or a mixture thereof, and may be used as an anhydride or a hydrate.

Furthermore, the metal alkoxide is represented by a general formula such as tetraethoxysilane [Si (OC ₂ H ₅ ) ₄ ], triisopropoxy aluminum [Al (O-2′-C ₃ H ₇ ) ₃ ], M (OR) _n ( M: metal such as Si, Ti, Al and Zr, R: alkyl group such as CH ₃ and C ₂ H ₅ ). Among these, tetraethoxysilane and triisopropoxyaluminum are preferable because they are relatively stable in an aqueous solvent after hydrolysis.

  Each of the above components can be used alone or in combination to form a coating layer, and further within the range that does not impair the gas barrier properties of the coating layer, isocyanate compound, silane coupling agent, dispersant, stabilizer, viscosity adjustment You may add additives, such as an agent and a coloring agent.

  For example, the isocyanate compound added to the coating layer (105) has two or more isocyanate groups (NCO groups) in the molecule, such as tolylene diisocyanate, triphenylmethane triisocyanate, tetramethylxylene diisocyanate, etc. Monomers and their polymers or derivatives.

  Conventionally known means such as a dipping method, a roll coating method, a screen printing method, a spray method and the like that are usually used can be used for the coating method for forming the coating layer (105). The thickness of the coating layer varies depending on the type of coating agent for forming the coating layer and the processing conditions, but it is sufficient that the thickness after drying is 0.01 μm or more, but if the thickness is 50 μm or more, the film will crack. Since it becomes easy, the range of 0.01-50 micrometers is preferable.

As a lamination | stacking method of the back surface protection sheet for solar cells of this invention, it can laminate | stack by well-known lamination methods, such as a dry lamination method. Adhesives used for the adhesive layers (106, 107) include adhesive strength between the fluororesin film (108) and the coating layer (105), and between the fluororesin film (109) and the film substrate (101). However, it is necessary that delamination due to deterioration does not occur during long-term outdoor use, and that the adhesive does not turn yellow. For example, polyurethane adhesives can be used. The adhesive can be applied by, for example, a roll coating method, a gravure roll coating method, a kiss coating method, a coating method such as others, or a printing method. The amount is preferably about 0.1 to 10 g / m ² (dry state).

  Next, specific examples of the present invention will be described.

Example 1
A 25 μm-thick polyvinyl fluoride film (DuPont Co., Ltd. trade name: Tedlar) is mounted on the unwinding roll (4) of the vacuum film forming apparatus (1), and the inside of the vacuum film forming apparatus (1) is 1.0 × 10. ^The pressure was reduced to ^-3 Pa. On the process roll (3), perfluorooctylethyl acrylate (Kyoeisha Chemical Co., Ltd., light acrylate FA-108) is added to the active energy ray-curable resin raw material layer A resin vapor deposition apparatus (6), and 3-acryloxypropyltrimethoxysilane. (Shin-Etsu Chemical Co., Ltd., KBM5103) is supplied to the active energy ray curable resin raw material layer B resin deposition apparatus (7), respectively, and the thickness of the cured active energy ray curable resin layer AB (102, 103) is Control was made to be 1.0 μm. The acceleration voltage irradiated by the electron beam irradiation apparatus (8) was 10 kV.

Further, an HMDSO flow rate: 10 sccm and an O ₂ flow rate of 100 sccm were introduced, a plasma was generated at a frequency of 13.56 MHz and a power of 1000 W, and the active energy ray curable resin layer B (102, 103) was brought into close contact with the process roll (3). An inorganic compound layer (104) made of a silicon oxide film was formed on the surface by chemical vapor deposition (CVD).

<Adjustment of coating solution for coating layer (105)>
(1) Preparation of component a liquid for coating layer
77.9 g of hydrochloric acid (0.1N) is added to 17.9 g of tetraethoxysilane [Si (OC ₂ H ₅ ) ₄ ] and 10 g of methanol, and the mixture is stirred for 30 minutes and hydrolyzed to a solid content of 5% by weight (weight ratio SiO 2 ₂ component) a component liquid was adjusted.
(2) Adjustment of component b liquid for coating layer
A polyvinyl alcohol resin was dissolved in a mixed solvent of water / methanol = 95/5 (weight ratio) to prepare a component b liquid having a solid content of 5% by weight.
(3) Preparation of component c liquid for coating layer
Hydrochloric acid (1N) was added little by little to a solution of γ-glycidoxypropyltrimethoxysilane and isopropyl alcohol (IPA), stirred for 30 minutes and hydrolyzed, and then a water / IPA = 1/1 mixture was added. Hydrolysis was carried out to prepare a component c liquid having a solid content of 5% by weight (weight ratio R ² Si (OH) ₃ conversion).

  Subsequently, using each of the component liquids a to c, a component liquid / b component liquid / c component liquid = 70/20/10 (solid content weight ratio) was formulated, and the gas barrier coating layer was used. The coating solution was adjusted.

Using the prepared coating solution, a coating layer (105) composed of a dry coating having a thickness of 0.1 μm was laminated to prepare a gas barrier film. Subsequently, on the surface of the coating layer (105) of the gas barrier film, a polyurethane adhesive (main agent Takelac A511 / curing agent Takenate A50 = 10/1 solution) manufactured by Mitsui Chemicals Polyurethane Co., Ltd. was used, and the coating amount was 5 g / An adhesive layer (106) made of an adhesive in m ² (dry state) is laminated, and a polyvinyl fluoride film (DuPont, trade name: Tedlar) having a thickness of 50 μm is formed thereon as a fluorine resin film layer (108). Further, an adhesive layer (107) made of an adhesive having an application amount of 5 g / m ² (dry state) using the same polyurethane adhesive as described above on the opposite surface of the film base layer (101). And a polyvinyl fluoride film (DuPont, trade name: Tedlar) having the same thickness of 50 μm as above is laminated as a fluorine-based resin film layer (109). The back surface protection sheet for solar cells of this invention (FIG. 3) was created.

Comparative Example 1
In Example 1, the back surface protection sheet for solar cells (FIG. 4) was created like Example 1 except not providing an organic compound layer and providing the film base material with the inorganic compound layer (104) directly.

Comparative Example 2
In Example 1, instead of aggregating the organic compound layer in vacuum, the back surface for solar cell was the same as in Example 1 except that the film substrate was subjected to plasma treatment and provided with an inorganic compound layer (104). A protective sheet (FIG. 5) was prepared.

Comparative Example 3
In Example 1, instead of agglomerating the organic compound layer in a vacuum, it was applied by gravure coating and cured with an electron beam to obtain an active energy ray curable resin layer A (110), an active energy ray curable resin layer. Back surface protection for solar cells in the same manner as in Example 1 except that B (111) is provided and an inorganic compound layer (104) is provided on the surface of the active energy ray-curable resin layer B (111) in the same manner as in Example 1. A sheet (FIG. 6) was created. As a reaction initiator, 1-hydroxycyclohexyl phenyl ketone (manufactured by Ciba Specialty Chemicals, Irgacure 184) was used.

Evaluation The water vapor permeability of the back protective sheets for solar cells of Example 1 and Comparative Examples 1 to 3 was measured according to JIS K7129 under the conditions of a temperature of 40 ° C. and a humidity of 90% RH (model name, perm). Tran).
Further, the laminate strengths of Example 1 and Comparative Examples 1 to 3 were measured by cutting the back protective sheet for solar cells into a width of 15 mm, performing a 180 degree peeling test with a tensile tester at a pulling speed of 50 mm / min.

As an evaluation standard, the barrier property was evaluated as ○ when the water vapor permeability was 1 (g / m ² · day) or less, and x when less than 1 (g / m ² · day).
For the adhesion, a laminate strength of 8 (N / 15 mm) or more was evaluated as “◯”, and less than 8 (N / 15 mm) was evaluated as “x”.
The evaluation results are shown in Table 1.

  As shown in Table 1, the back protective sheet for solar cells provided with the laminate of the present invention obtained in Example 1 has a higher water vapor barrier property than the back protective sheets for solar cells produced in Comparative Examples 1 to 3. It was confirmed that it has adhesiveness. Since Comparative Example 1 was a polyvinyl fluoride film substrate, adhesion to the gas barrier layer was weak without treatment and without coating. In Comparative Example 2, the film substrate was subjected to plasma treatment to roughen the surface, and thus the adhesion was strong but the barrier property was poor. Comparative Example 3 is different from Example 1 in that the organic compound layer is thick and not smooth, and the two organic compound layers and the inorganic compound layer are separately solidified in separate processes, so the adhesion is weak and cracks are generated due to shrinkage. And the barrier property was also bad.

It is a schematic diagram of the apparatus which can be used for manufacture of the laminated body of invention. It is sectional drawing of an example of the laminated body of this invention. It is sectional drawing of an example of the back surface protection sheet for solar cells using the laminated body of this invention. It is sectional drawing of the back surface protection sheet for solar cells of the comparative example 1. FIG. It is sectional drawing of the back surface protection sheet for solar cells of the comparative example 2. FIG. It is sectional drawing of the back surface protection sheet for solar cells of the comparative example 3. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Vacuum film-forming apparatus 2 ... Vacuum pump A
DESCRIPTION OF SYMBOLS 3 ... Process roll 4 ... Unwinding roll 5 ... Winding roll 6 ... Active energy ray hardening resin raw material layer A resin vapor deposition apparatus 7 ... Active energy ray hardening resin raw material layer B resin vapor deposition apparatus 8 ... Electron beam irradiation device 9 ... Shielding plate A
DESCRIPTION OF SYMBOLS 10 ... Inorganic compound layer forming apparatus 11 ... Active energy ray hardening resin layer A resin raw material supply apparatus 12 ... Active energy ray hardening resin layer B resin raw material supply apparatus 13 ... Gas supply apparatus 14 ... Vacuum pump B
15 ... Vacuum pump C
16 ... Pressure regulating valve A
17 ... Pressure regulating valve B
18 ... Shield plate B
19 ... Shielding plate C
101 ... Substrate 102 ... Active energy ray curable resin layer A
103 ... Active energy ray curable resin layer B
104 ... Inorganic compound layer 105 ... Coating layer 106 ... Adhesive layer 107 ... Adhesive layer 108 ... Fluorine resin film layer 109 ... Fluorine resin film layer 110 ... Activity Energy ray curable resin layer A
111... Active energy ray cured resin layer B

Claims (7)

A laminate in which an organic compound layer and an inorganic compound layer are sequentially provided on at least one surface of a fluorine resin film,
The organic compound layer is at least
Formed on said fluorine-based resin film, including the including organic compound layer A fluorine compound having an addition-polymerizable functional group, the molecular weight has a trialkoxysilyl group 150 to 600 and (meth) acrylic compound, and An organic compound layer B formed on the side in contact with the inorganic compound layer,
Curing the organic compound layer A and the organic compound layer B by active energy ray irradiation or plasma irradiation,
The organic compound layer and the inorganic compound layer before curing are formed using a vapor deposition method in a vacuum atmosphere. The organic compound layer A and the organic compound layer B before curing are sequentially deposited on the fluororesin film in a vacuum atmosphere, and then aggregated and simultaneously cured by irradiation with active energy rays or plasma. The laminate according to claim 1, which is characterized.   The laminate according to claim 1 or 2, wherein the addition polymerization functional group is an acryl group or a methacryl group.   The laminate according to claim 1, wherein the organic compound layer is formed using a flash vapor deposition method.   The laminate according to any one of claims 1 to 4, wherein the inorganic compound layer is formed using a chemical vapor deposition (CVD) method.   The laminate according to any one of claims 1 to 5, wherein the organic compound layer and the inorganic compound layer are formed in the same vacuum without being exposed to the atmosphere.   The back surface protection sheet for solar cells characterized by bonding a fluorine-type resin film on both surfaces of the laminated body in any one of Claims 1-6 through an adhesive agent.

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