JP2011060791A - Backside protecting sheet for solar cell module, and solar cell module manufactured using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a backside protecting sheet for a solar cell module, superior in durability under a high temperature and high humidity environment and suppressed in secular deterioration of strength, barrier performance and light reflection index, and to provide a solar cell module manufactured using the sheet. <P>SOLUTION: The backside protecting sheet 10 for the solar cell module is formed by sequentially laminating a transparent polyester-based resin film 1, a substrate polyester-based resin film 4 having at least one layer of each of a deposited film 2 of an inorganic oxide and a gas barrier coating film 3 on at least one surface and at least a layer of composite resin film 5 via adhesive layers 6, 7. Either or both of the transparent polyester-based resin film 1 and the composite resin film 5 contain a rutile type oxide titanium. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a back surface protection sheet for solar cell modules (hereinafter, also simply referred to as “back surface protection sheet”) and a solar cell module using the same, and more specifically, a back surface protection sheet for solar cell modules comprising a laminated structure of resin films. And a solar cell module using the same.

  In recent years, solar cells have attracted attention as a clean energy source due to increasing awareness of environmental problems, and solar cell modules having various forms have been developed and proposed.

  In general, a solar cell module has a basic structure in which a surface protection sheet, a filler layer, a solar cell element, a filler layer, and a back surface protection sheet are sequentially laminated, and generates electricity when sunlight enters the solar cell element. It has a function. Since the solar cell is mainly used outdoors, the protective sheet for protecting the solar cell element needs to have high durability. Especially, the back surface protective sheet has hydrolysis resistance, weather resistance, water vapor barrier property, It is required to have various functions such as adhesion to the filler and insulation.

  For this reason, the back surface protection sheet is usually configured as a composite sheet composed of a plurality of layers. Conventionally used back surface protection sheets for solar cell modules are most commonly used plastic substrates with excellent strength, such as polypropylene resin or polyethylene terephthalate resin, and are used for bonding between layers. As the agent, for example, rubber adhesives such as butadiene rubber, urethane adhesives, and the like are widely used.

  As an improved technique relating to such a back surface protection sheet, for example, Patent Document 1 discloses that a coloring additive, an ultraviolet absorber, and light stabilization are provided on both surfaces of a base film provided with an inorganic oxide vapor deposition film on one surface. A back protective sheet for a solar cell module is disclosed in which a colored polypropylene resin film containing an agent is laminated via an adhesive layer for laminating. In this case, the water vapor barrier property is secured by the inner base film having an inorganic oxide vapor deposition film, and the hydrolysis resistance and weather resistance are secured by the outer polypropylene resin film.

  Patent Document 2 discloses a base film made of a fluorine resin film, a cyclic polyolefin resin film, a polycarbonate resin film, a poly (meth) acrylic resin film, a polyamide resin film, or a polyester resin film. A heat-resistant polypropylene-based resin film containing a whitening agent and an ultraviolet absorber is provided on both sides of a base film provided with an inorganic oxide vapor-deposited film on one side, and further provided with the above-described inorganic oxide vapor-deposited film. The laminated back surface protection sheet for solar cell modules is disclosed, and it is also disclosed that anatase titanium oxide or rutile titanium oxide can be used as a whitening agent.

JP 2003-168814 A (Claims etc.) Japanese Patent No. 4217935 (claims, etc.)

  Conventional back surface protection sheets for solar cell modules as disclosed in the above patent documents are excellent in strength and can satisfy various requirements such as hydrolysis resistance and weather resistance. However, with the recent improvement in conversion efficiency and longer life of solar cell modules, the durability under severe usage conditions of high temperature and high humidity is further improved, and the strength, barrier performance, and light reflectance are decreased over time. There was a need to establish technologies that could prevent it.

  Accordingly, an object of the present invention is to provide a back surface protection sheet for a solar cell module that is excellent in durability under a high temperature and high humidity environment, and that suppresses a decrease in strength, barrier performance, and light reflectance over time, and a solar cell module using the same. There is to do.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have added high rutile titanium oxide to the film constituting the surface of either or both of the back surface protection sheets for solar cell modules, thereby increasing the temperature and the temperature. The inventors have found that strength, barrier performance, and light reflectance in a wet environment can be suppressed, and have completed the present invention.

That is, the back surface protection sheet for solar cell modules of the present invention is a transparent polyester resin film and a base polyester resin film having at least one layer of an inorganic oxide vapor deposition film and a gas barrier coating film on at least one surface. And at least one synthetic resin film is a back surface protection sheet for solar cell modules, which is sequentially laminated via an adhesive layer,
Either one or both of the transparent polyester-based resin film and the synthetic resin film contain rutile-type titanium oxide.

The solar cell module of the present invention is a solar cell module in which a surface protective sheet, a filler layer, a solar cell element, a filler layer, and a back surface protective sheet are sequentially laminated,
The back surface protection sheet is the back surface protection sheet for a solar cell module of the present invention, and the filler layer and the synthetic resin film are laminated so as to face each other.

  According to the present invention, the above configuration makes it possible to use the back protective sheet for a solar cell module, which has excellent durability under a high temperature and high humidity environment, and is capable of suppressing the deterioration of strength, barrier performance, and light reflectance over time. It became possible to realize the solar cell module that had been.

It is typical sectional drawing which shows the back surface protection sheet for solar cell modules which concerns on one embodiment of this invention. It is typical sectional drawing which shows the solar cell module which concerns on one embodiment of this invention. It is a schematic block diagram which shows an example of a winding-type vacuum deposition apparatus. It is a schematic block diagram which shows a low-temperature plasma chemical vapor deposition apparatus.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the present invention, the term “sheet or film” means any sheet or film.

  In FIG. 1, typical sectional drawing of the back surface protection sheet for solar cell modules of an example of this invention is shown. The back surface protection sheet 10 shown in the figure includes a transparent polyester resin film 1, a base polyester resin film 4 having a vapor-deposited film 2 of inorganic oxide and a gas barrier coating film 3, and a synthetic resin film 5. 6 and 7 are sequentially stacked.

  In the present invention, it is important that either one or both of the transparent polyester resin film 1 and the synthetic resin film 5 constituting the surface of the back protective sheet contain rutile titanium oxide. Titanium oxide is an additive conventionally known as a whitening agent. In the present invention, rutile type titanium oxide is particularly blended among titanium oxides in a film constituting the surface of the back protective sheet. The present inventors have found that it is possible to effectively suppress a decrease in light reflectivity and mechanical strength in a high-temperature and high-humidity environment and an ultraviolet irradiation environment.

  The light reflectance can be improved by blending rutile titanium oxide with the synthetic resin film 5 constituting the sheet surface on the side irradiated with light. Further, by incorporating rutile type titanium oxide into the transparent polyester resin film 1 constituting the sheet surface that comes into contact with the outside air when incorporated into a solar cell module, the UV (ultraviolet) resistance can be improved. it can. Therefore, in any case, in the present invention, it is possible to suppress the environmental deterioration of the film and maintain the strength, barrier performance, and reflectance of the back surface protection sheet better for a longer period.

  In the present invention, the content of rutile titanium oxide in each film is preferably 1 to 30% by mass, particularly 5 to 25% by mass of the resin composition constituting the film. If the content of rutile-type titanium oxide is too small, the desired effect of the present invention cannot be obtained sufficiently. On the other hand, when there is too much content of a rutile type titanium oxide, the fluidity | liquidity of a compound will fall and the extrusion property at the time of shape | molding a film will deteriorate. Moreover, as this rutile type titanium oxide, a thing with an average particle diameter of 0.1-3.0 micrometers can be used conveniently.

(Transparent polyester resin film)
The transparent polyester-based resin film 1 used in the present invention is excellent in tight adhesion with a deposited inorganic oxide vapor-deposited film, etc., and can be favorably retained without impairing the characteristics of those films, and has a strength. Excellent weather resistance, heat resistance, water resistance, light resistance, wind pressure resistance, yield resistance, chemical resistance, and other fastnesses, especially moisture resistance to prevent intrusion of moisture, oxygen, etc. Further, it has a high surface hardness, an excellent antifouling property for preventing the accumulation of dirt, dust and the like on the surface, an extremely rich durability, and a high protective ability.

  As the transparent polyester resin film 1, a polyester film having a carboxy terminal group amount of 15 equivalent / ton or less, particularly 12 equivalent / ton to 5 equivalent / ton can be preferably used. By using such a polyester film, the back surface protective sheet of the present invention can be made excellent in hydrolysis resistance, and durability can be improved.

  In addition, the amount of the above carboxy terminal group is determined based on a certain amount of film of orthocresol / chloroform (mass ratio = 50/50 or 60/40), phenol / 1,2-dichlorobenzene (mass ratio = 50/50), phenol / It can be determined by dissolving in 1,1,2,2-tetrachloroethane (mass ratio = 50/50 or 60/40), O-chlorophenol and dichloroacetic acid, and performing potentiometric titration with alkali.

  The transparent polyester resin film 1 according to the present invention preferably has an intrinsic viscosity of 0.8 dl / g or more. By using the polyester resin having an intrinsic viscosity of 0.8 dl / g or more, the back surface protective sheet of the present invention can be made excellent in toughness, rigidity and heat resistance. In the present invention, it is more preferable to use a polyester-based resin having an intrinsic viscosity of 1.0 dl / g or more, more preferably a polyester having an intrinsic viscosity in the range of 1.2 dl / g to 1.5 dl / g. System resin is used.

  The intrinsic viscosity means that the film is phenol / 1,2-dichlorobenzene (mass ratio = 50/50), phenol / 1,1,2,2-tetrachloroethane (mass by mass) at a concentration of 0.1 g / ml. Ratio = 50/50 or 60/40), the viscosity at 25 ° C. of a solution dissolved in any solvent of O-chlorophenol and dichloroacetic acid.

Here, in general, measuring the viscosity in a dilute solution of fine particles or a polymer substance can be very useful for knowing their physical properties in a simple manner. The ratio η _r = η / η ₀ between the viscosity η of the solution in which the target substance is dissolved and the viscosity η _{0 of} the solvent is called relative viscosity. The viscosity η _{SP obtained} by subtracting 1 from this relative viscosity η _r , that is, η _SP = Η _r1 = (η−η ₀ ) / η _0, is called specific viscosity, and the increase in viscosity due to the dissolution of the target substance in the solvent. It corresponds to. The specific viscosity η _SP is a function of the concentration of the target substance, and the extrapolated value of the specific viscosity to 0 is the intrinsic viscosity (extreme viscosity). Such intrinsic viscosity is a physical quantity that can be related to the particle size and molecular weight of a solute dispersed in a solution, and contains a lot of useful information. The viscosity of the above solution is a value measured according to JIS K7367-5 (Plastic-Determination of viscosity of polymer diluted solution using capillary viscometer-Part 5: Thermoplastic polyester (TP) homopolymer and copolymer). Shall be used.

  In addition, there is a correlation between the content of the oligomer in the polyester resin and the amount of the carboxy terminal group, and as the content of the oligomer increases, the amount of the carboxy terminal group increases and the hydrolysis resistance decreases. On the other hand, the smaller the oligomer content, the smaller the amount of carboxy end groups, so the hydrolysis resistance is improved. Therefore, in the present invention, the polyester-based resin having an oligomer content of 0.4% by mass or less, particularly 0.3 to 0.1% by mass, more preferably 0.2 to 0.1% by mass. It is preferable to use from the viewpoint of further improving the hydrolysis resistance.

  In addition, the said oligomer means here the low polymer whose repeating number (polymerization degree) of the structural unit which comprises the said polyester-type resin is about 2-20. The oligomer content in the polyester resin is, for example, phenol / 1,2-dichlorobenzene (mass ratio = 50/50), phenol / 1,1,2,2-tetrachloroethane (mass ratio = 50/50 or 60/40), 100 mg of a polyester resin dissolved in 2 ml of any solvent such as O-chlorophenol and dichloroacetic acid is measured by liquid chromatography (for example, manufactured by HLC803D Toso Co., Ltd.). It can be shown by the ratio (mass%) of the oligomer.

  In addition, there is a correlation between the number average molecular weight of the polyester resin and the amount of carboxy terminal groups in the transparent polyester resin film, and as the number average molecular weight increases, the amount of carboxy terminal groups decreases. On the other hand, when the number average molecular weight is lowered, the hydrolysis resistance is improved because the amount of the carboxy terminal group is increased. Therefore, in the present invention, it is preferable to use a polyester-based resin having a number average molecular weight in the range of 18500 to 40000, particularly 19000 to 35000, from the viewpoint of further improving the hydrolysis resistance.

In addition, as said number average molecular weight, the value measured on condition of the following by GPC (gel permeation chromatography) method shall be used.
(A) Apparatus: Gel permeation chromatograph GCP-244 (manufactured by WATERS)
(B) Column: Two Shodex HFIP 80M (made by Showa Denko KK)
(C) Solvent: Hexafluoropropanol (0.005N-sodium trifluoroacetate)
(D) Flow rate: 0.5 ml / min
(E) Temperature: 23 ° C
(F) Sample Concentration: 0.06%, Solubility: Complete dissolution, Filtration: Maisho Disc W-13-5
(G) Injection amount: 0.300 ml
(H) Detector: R-401 type differential refractometer (WATERS)
(I) Molecular weight fair: PET-DMT (standard product)

  The polyester resin used in the present invention is not particularly limited as long as it has a structure obtained by condensing a dicarboxylic acid compound and a diol compound.

  The dicarboxylic acid compound is not particularly limited, and for example, aromatic dicarboxylic acid, alicyclic dicarboxylic acid or aliphatic dicarboxylic acid can be used. As the aromatic dicarboxylic acid, examples of the aromatic dicarboxylic acid component include terephthalic acid, isophthalic acid, phthalic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4′-diphenyldicarboxylic acid, 4,4′-diphenylether dicarboxylic acid, 4,4′-diphenylsulfonedicarboxylic acid and the like can be mentioned. Among these, in the present invention, terephthalic acid, phthalic acid, and 2,6-naphthalenedicarboxylic acid can be preferably used. Examples of the alicyclic dicarboxylic acid include cyclohexane dicarboxylic acid. Furthermore, examples of the aliphatic dicarboxylic acid component include adipic acid, suberic acid, sebacic acid, dodecanedioic acid and the like. In addition, the said dicarboxylic acid compound may use only 1 type, may use 2 or more types together, Furthermore, you may copolymerize partially oxy acids, such as hydroxyethoxybenzoic acid.

  The diol compound is not particularly limited as long as it can be condensed with the dicarboxylic acid to form a polyester resin. Examples of the diol compound include ethylene glycol, 1,2-propanediol, 1,3-propanediol, neopentyl glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, diethylene glycol, triethylene glycol, polyalkylene glycol, 2,2′-bis (4 ′ -Β-hydroxyethoxyphenyl) propane and the like. Among these, ethylene glycol, 1,4-butanediol, 1,4-cyclohexanedimethanol, diethylene glycol are preferably used, and ethylene glycol is most preferably used. In addition, the said diol component may use only 1 type and may use 2 or more types together.

  In the present invention, it is preferable to use polyethylene terephthalate, polyethylene naphthalate, polyethylene-2,6-naphthalenedicarboxylate among polyester resins, and it is more preferable to use polyethylene terephthalate.

  The polyester-based resin includes other compounds such as monofunctional compounds such as trimellitic acid, pyromellitic acid, glycerol, pentaerythritol, 2,4-dioxybenzoic acid, lauryl alcohol, and phenyl isocyanate. The copolymer may be copolymerized within a substantially linear range.

  For example, the polyester resin may be produced by directly esterifying an acid component and a diol component, or using a dialkyl ester as an acid component and performing a transesterification reaction with a diol component. In addition, the reaction product is heated under reduced pressure to remove the excess diol component and melt polymerization is carried out to remove the excess diol component, and the second stage reaction product is further subjected to solid phase polymerization. Examples include a method of producing using a three-stage reaction. In the present invention, it is preferable to use solid phase polymerization in order to obtain a polyester resin having a small amount of carboxy end groups.

  The solid phase polymerization method is not particularly limited, and a conventionally known method can be used. For example, a method of preliminarily crystallizing at a temperature of 180 ° C. or lower in advance and then heating at a temperature in the range of 180 ° C. to a melting point (about 250 ° C.) for 5 to 50 hours in a nitrogen flow or in a vacuum of 1 torr or lower. Can be used.

  The polyester resin used in the present invention may contain a polyether compound for the purpose of adjusting the intrinsic viscosity to a desired range, for example. Such a polyether compound is not particularly limited, and for example, a polyether compound containing polyethylene oxide or diol as a main constituent can be used.

  Examples of the diol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, neopentyl glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6 -Hexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, diethylene glycol, triethylene glycol, polyalkylene glycol, 2,2'-bis (4'-β- Hydroxyethoxyphenyl) propane and the like can be mentioned.

  Examples of the polyether compound preferably used in the present invention include a polyether compound containing at least one of polyethylene oxide, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and a copolymer of these polyether compounds. Can be mentioned.

  In addition, as the polyether compound, an end-capped polyether compound may be used. This is because the end-capped polyether compound has an advantage that the hydrolysis of the polyester resin can be suppressed. Examples of the end-capped polyether compound include a polyether compound in which a polyether end hydroxyl group is alkyl etherified, that is, end-capped with a methoxy group, an ethoxy group, or the like.

  Although it does not specifically limit as an average molecular weight of the said polyether compound, It is preferable that it is 500-10000, More preferably, it is 700-5000. If the average molecular weight is less than 500, it is disadvantageous in that it is contained in the polyester resin. On the other hand, when the average molecular weight exceeds 10,000, the compatibility with the polyester resin may be deteriorated.

  Although it does not specifically limit as content of this polyether compound, Usually, it is preferable to exist in the range of 0.1-10 mass% in a polyester-type resin, and the inside of the range of 0.2-7 mass% is especially preferable. Particularly preferred is a range of 0.2 to 5% by mass.

  In addition, the above polyester resins include flame retardants, heat stabilizers, antioxidants, ultraviolet absorbers, antistatic agents, pigments, dyes, fatty acid esters, waxes and other organic lubricants, or polysiloxanes as necessary. An antifoaming agent can be blended. In addition, clay, mica, calcium carbonate, carion, talc, wet or dry silica, colloidal silica, calcium phosphate, barium sulfate, alumina, zirconia, etc. Mixing particles, organic particles containing acrylic acid, styrene, etc. as constituents, adding so-called internal particles that are precipitated by a catalyst added during the polyester polymerization reaction, or adding a surfactant Also good.

The apparent density of the transparent polyester-based resin film 1 used in the present invention is not particularly limited as long as the desired mechanical strength can be imparted. Particularly, in the present invention, it is preferable that the apparent density is in the range of ^{0.85g / cm 3 ~1.37g / cm 3} , more preferably 0.9g ^/ cm ³ ~1.35g ^/ cm 3 range, more preferably in the range of ^{0.9g / cm 3 ~1.3g / cm 3} . This apparent density can be determined by measuring the mass of a film whose volume is known.

  Moreover, it does not specifically limit as thickness of the transparent polyester-type resin film 1, It can determine arbitrarily within the range which can provide desired self-supporting property to the back surface protection sheet of this invention. In particular, in the present invention, the thickness is preferably in the range of 3 to 500 μm, more preferably in the range of 25 to 250 μm, and still more preferably in the range of 25 to 188 μm. Especially, when using a polyethylene terephthalate film, thickness 50-188 micrometers is suitable, and when using a polyethylene naphthalate film, thickness 25-188 micrometers is suitable. In addition, this thickness shall use the value measured based on the JIS C2151 electrical plastic film test method.

Further, from the viewpoint of short circuit resistance of the back protective sheet, the volume specific resistance of the transparent polyester resin film is preferably about 1 × 10 ¹⁸ Ω / cm, and the dielectric breakdown voltage is preferably in the range of 5 to 50 kV. In addition, the dielectric constant is preferably about 3.3 (1 kHz). In addition, these characteristics shall use the value measured based on the JIS C2151 electrical plastic film test method.

  The method for producing the transparent polyester resin film 1 is not particularly limited as long as it is a method capable of uniformly forming a film with a desired thickness. For example, one or more of the above-mentioned various resins are used, and the above-mentioned various resins are formed using film forming methods such as an extrusion method, a cast molding method, a T-die method, a cutting method, and an inflation method. A method of forming a film alone, or a method of forming a multilayer co-extrusion film using two or more kinds of resins, and further using two or more kinds of resins and mixing them in advance to form a film. Various resin films or sheets produced by a method, etc., and, if desired, for example, various resins formed by stretching in a uniaxial or biaxial direction using a tenter method or a tubular method. Films or sheets can be used.

  In forming a film using one or more of the above-mentioned various resins, for example, film processability, heat resistance, light resistance, weather resistance, mechanical properties, dimensional stability, antioxidant properties, slipping, etc. Various plastic compounding agents, additives, and the like can be added for the purpose of improving and modifying properties, mold release properties, flame retardancy, antifungal properties, electrical properties, and the like. The addition amount may be arbitrarily selected from a very small amount to several tens of mass% according to the purpose. Common additives include, for example, lubricants, crosslinking agents, antioxidants, UV absorbers, light stabilizers, fillers, lubricants, reinforcing fibers, reinforcing agents, antistatic agents, flame retardants, flame retardants, foaming Agents, fungicides, pigments, and the like, and a modifying resin may be used. In the present invention, among the above additives, it is particularly preferable to use films or sheets of various resins obtained by kneading and processing an ultraviolet absorber, a light stabilizer, an antioxidant, or the like.

  Among the above, UV absorbers absorb harmful UV rays in sunlight and convert them into innocuous heat energy within the molecule, preventing the activation of photo-degraded active species in polymers. For example, benzophenone-based, benzotriazole-based, salicylate-based, acrylonitrile-based, metal complex-based, and ultrafine titanium oxide having a particle size of 0.01 to 0.06 μm or a particle size of 0.01 to 0. 0. One or two or more kinds of inorganic ultraviolet absorbers composed of ultrafine zinc oxide of 04 μm can be used. Moreover, as a light stabilizer, 1 type, or 2 or more types, such as a hindered amine type compound and a hindered piperidine type compound, can be used, for example. Furthermore, the antioxidant is used to prevent oxidative degradation of the polymer due to light or heat, and for example, a phenol-based, amine-based, sulfur-based or phosphoric acid-based antioxidant can be used. . Furthermore, as the above-mentioned ultraviolet absorber, light stabilizer or antioxidant, for example, a light stabilizer comprising the above-mentioned UV absorber such as benzophenone or a hindered amine compound in the main chain or side chain constituting the polymer. Polymer-type ultraviolet absorbers, light stabilizers, antioxidants, and the like obtained by chemically bonding a oxidant or a phenol-based antioxidant can also be used. The content of the ultraviolet absorber, light stabilizer or antioxidant is preferably 0.1 to 10% by mass, although it varies depending on the particle shape, density and the like.

  In the present invention, the surface of the transparent polyester-based resin film 1 is provided with a desired surface treatment layer in advance, if necessary, in order to improve close adhesion with an inorganic oxide vapor deposition film or the like. Can do. As such a surface treatment layer, for example, pretreatment such as corona discharge treatment, ozone treatment, plasma treatment using oxygen gas or nitrogen gas, glow discharge treatment, oxidation treatment using chemicals or the like is optionally performed. And a surface-treated surface such as a corona-treated surface, an ozone-treated surface, a plasma-treated surface, and an oxidized-treated surface. The surface pretreatment may be performed in a separate process. For example, in the case of surface pretreatment by plasma treatment, glow discharge treatment, or the like, as a pretreatment for forming the above-described inorganic oxide deposition film or the like. The pre-processing may be performed by in-line processing. In such a case, there is an advantage that the manufacturing cost can be reduced.

  In addition, as a method for improving the tight adhesion between the transparent polyester resin film 1 and a vapor deposition film of an inorganic oxide, for example, a primer coat agent layer, A coating agent layer, an anchor coating agent layer, an adhesive layer, a vapor deposition anchor coating agent layer, or the like can be arbitrarily formed to form a surface treatment layer. Examples of the pretreatment coating agent layer include polyester resins, polyamide resins, polyurethane resins, epoxy resins, phenol resins, (meth) acrylic resins, polyvinyl acetate resins, polyethylene, and polypropylene. A resin composition comprising a main component of a vehicle such as a polyolefin resin or a copolymer or modified resin thereof, a cellulose resin, or the like can be used.

  In addition, additives such as an epoxy-based silane coupling agent for improving the tight adhesion or an anti-blocking agent for preventing blocking of the base film are optionally added to the above resin composition can do. The addition amount is preferably in the range of 0.1 to 10% by mass. Moreover, in this invention, in order to improve light resistance etc., for example, a ultraviolet absorber, a light stabilizer, antioxidant etc. can be added in said resin composition. As the ultraviolet absorber, light stabilizer, or antioxidant, one or more of the above-described ultraviolet absorber, light stabilizer, or antioxidant can be used in the same manner. The content of such an ultraviolet absorber varies depending on the particle shape, density, and the like, but is preferably in the range of 0.1 to 10% by mass.

  In addition, as a method for forming the coating agent layer, for example, a solvent type, an aqueous type, or an emulsion type coating agent is used, and a coating method such as a roll coating method, a gravure roll coating method, or a kiss coating method is used. The coating can be performed after the sheet is formed, as a post-process after the biaxial stretching process, or in-line processing of the film forming or biaxial stretching process, or the like. .

(Base polyester resin film)
The base polyester-based resin film 4 according to the present invention can be basically the same as the transparent polyester-based resin film 1 described above, and an inorganic oxide vapor-deposited film 2 on at least one surface. Therefore, it is preferable to use a material that can withstand vapor deposition conditions and the like when forming an inorganic oxide vapor deposition film or the like. The thickness of the base polyester-based resin film 4 is not particularly limited, and is preferably in the range of 9 to 150 μm, more preferably in the range of 12 to 125 μm.

  In the present invention, the base polyester resin film 4 is protected from vapor deposition conditions that damage the base polyester resin film 4 such as heat and ion bombardment when the inorganic oxide vapor deposition film is formed. Suppressing yellowing, deterioration or shrinkage, cohesive failure in the surface layer or inner layer of the film, etc., and forming a vapor-deposited film of inorganic oxide well, and a resin film and a vapor-deposited film of inorganic oxide A surface pretreatment layer can be provided on the base polyester resin film 4 in advance for the purpose of improving the tight adhesion and the like. Such a surface pretreatment layer is, for example, a chemical vapor deposition method (chemical vapor deposition (CVD) method) such as a plasma chemical vapor deposition method, a thermal chemical vapor deposition method, or a photochemical vapor deposition method described later, or vacuum deposition. Dry coating methods such as physical vapor deposition (PVD) methods such as sputtering (resistance heating, dielectric heating, EB heating), sputtering, ion plating, etc., and hydrolysis of inorganic fillers or metal alkoxides By forming a thin film containing at least one inorganic oxide by a wet coating method such as a roll coating method, a gravure roll coating method, or a kiss coating method using a resin mixture in which a condensate is dispersed, It can be provided as a protective layer.

  In the present invention, the base material protective layer made of an inorganic oxide such as silicon oxide is a thin film because the purpose of the dry coating method is to suppress deterioration of the base material during vapor deposition. Thus, a non-barrier film having no barrier property is sufficient, and it is desirable to form a film at a low output and a high speed so that the surface of the substrate is not decomposed or etched by heat addition or ion bombardment. Specifically, the film thickness is in the range of 10 to 100 mm, preferably in the range of 20 to 80 mm, and more preferably in the range of 30 to 60 mm. When the film thickness is greater than 100 mm, the substrate damage due to the deposition of the substrate protective layer increases, and it becomes difficult to form a good vapor deposition resistant protective film that is originally intended. On the other hand, if it is less than 10 mm, the surface layer of the base polyester-based resin film 4 is partially exposed, so that the function as the base protective layer is lost and it is difficult to achieve the effect. In the case of the wet coating method, the weight ratio of the inorganic compound in the components of the obtained dried coating film is preferably in the range of 10% to 90%, particularly in the range of 20% to 80%. If the weight ratio exceeds 80%, particularly more than 90%, the adhesion to the substrate is extremely low, cohesive failure and cracks are likely to occur, and it is not preferable to form a vapor deposition resistant protective film. . On the other hand, when the weight ratio is less than 20%, particularly less than 10%, the amount of the inorganic oxide is not sufficient, the function as the base material protective layer is lost, and it is difficult to achieve the effect, which is not preferable. .

  Next, the inorganic oxide vapor deposition film 2 provided on at least one surface of the base polyester-based resin film 4 in the present invention will be described. As the inorganic oxide vapor-deposited film, for example, a single-layer film composed of one layer of the inorganic oxide vapor-deposited film 2 by using physical vapor deposition, chemical vapor deposition, or a combination of both. Alternatively, a multilayer film or a composite film composed of two or more layers can be formed.

  Among these, the formation of an inorganic oxide vapor-deposited film by physical vapor deposition includes, for example, vacuum vapor deposition (resistance heating, dielectric heating, EB heating), sputtering, ion plating, ion cluster beam, etc. A physical vapor deposition method (PVD method) can be used. Specifically, a metal oxide is used as a raw material, and this is heated to deposit on a base film, or a metal or metal oxide is used as a raw material, and oxygen is introduced to oxidize. The vapor deposition film can be formed using an oxidation reaction vapor deposition method in which vapor deposition is performed on the base polyester resin film 4 and a plasma-assisted oxidation reaction vapor deposition method in which the oxidation reaction is supported by plasma. In the above, as a heating method for the vapor deposition material, for example, a resistance heating method, a high frequency induction heating method, an electron beam heating method (EB), or the like can be used.

  In the present invention, specific examples of the method for forming the inorganic oxide vapor-deposited film 2 by physical vapor deposition will be described. FIG. 3 is a schematic configuration diagram illustrating an example of a take-up vacuum deposition apparatus. As shown in FIG. 3, the base film 101 fed from the unwinding roll 23 in the vacuum chamber 22 of the wind-up type vacuum vapor deposition apparatus 21 is cooled by the coating drum 26 via the guide rolls 24 and 25. Be guided to. Next, the deposition source 28 heated by the crucible 27, for example, metal aluminum or aluminum oxide, is evaporated on the base film 101 guided on the cooled coating drum 26, and oxygen oxygen is added if necessary. A vapor deposition film of an inorganic oxide such as aluminum oxide is formed through the masks 30 and 30 while oxygen gas or the like is ejected from the gas outlet 29 and supplied. Next, the base film 101 on which the inorganic oxide vapor-deposited film is formed is sent out through the guide rolls 31 and 32 and wound up on the take-up roll 33, whereby the inorganic oxidation by the physical vapor deposition method according to the present invention is performed. A vapor deposition film of an object can be formed.

  In the present invention, the first-layer inorganic oxide vapor deposition film is first formed using the above-described winding-type vacuum vapor deposition apparatus, and then the first-layer inorganic oxide is similarly formed. On the deposited film, a second layer of an inorganic oxide deposited film is formed, or the above-described wound-type vacuum deposition apparatus is used to continuously connect the two layers, and continuously By forming an inorganic oxide vapor-deposited film, it is also possible to form an inorganic oxide vapor-deposited film consisting of two or more multilayer films.

In the above, as the inorganic oxide vapor-deposited film 2, basically any thin film on which a metal oxide is vapor-deposited can be used. For example, silicon (Si), aluminum (Al), magnesium (Mg), calcium (Ca), potassium (K), tin (Sn), sodium (Na), boron (B), titanium (Ti), lead (Pb), zirconium (Zr), yttrium (Y) and other metal oxides Vapor deposited films can be used. Among these, a vapor deposition film of a metal oxide such as silicon (Si) or aluminum (Al) is preferable. The metal oxide vapor-deposited film can be referred to as a metal oxide such as silicon oxide, aluminum oxide, magnesium oxide, and the like, for example, SiO _X , AlO _X , MgO _X, etc. MO X _(in the formula, M represents a metal element, the value of X, each range differs by the metal element) as represented by. Moreover, as a range of said X value, silicon (Si) is 0-2, aluminum (Al) is 0-1.5, magnesium (Mg) is 0-1, calcium (Ca) is 0-1, 0 to 0.5 for potassium (K), 0 to 2 for tin (Sn), 0 to 0.5 for sodium (Na), 0 to 1 for boron (B), 0 to 2 for titanium (Ti). Lead (Pb) can take values in the range of 0 to 1, zirconium (Zr) in the range of 0 to 2, and yttrium (Y) in the range of 0 to 1.5. In the above, when X = 0, it is a complete metal and is not transparent and cannot be used at all. In addition, the upper limit of the range of X is a completely oxidized value. In the present invention, generally, examples other than silicon (Si) and aluminum (Al) are poor, and silicon (Si) is 1.0 to 2.0, and aluminum (Al) is 0.5 to 1. A value in the range of .5 can be used. In the present invention, the thickness of the vapor-deposited film of the inorganic oxide as described above varies depending on the type of metal or metal oxide used, but is within the range of 50 to 4000 mm, preferably 100 to It can be arbitrarily selected and formed within the range of 1000 Å, more preferably within the range of 300 to 800 Å. In the present invention, the inorganic oxide vapor-deposited film is used as a metal or metal oxide to be used in one kind or a mixture of two or more kinds, and constitutes an inorganic oxide vapor-deposited film mixed with different materials. You can also

  Next, an inorganic oxide vapor deposition film formed by chemical vapor deposition will be described. For example, the chemical vapor deposition method (CVD method) such as plasma chemical vapor deposition method, thermal chemical vapor deposition method, photochemical vapor deposition method, etc. can be used to form the inorganic oxide vapor-deposited film by the chemical vapor deposition method. Etc. can be used. Specifically, on one surface of the resin film, a monomer gas for vapor deposition such as an organosilicon compound is used as a raw material, an inert gas such as argon gas or helium gas is used as a carrier gas, and further, as an oxygen supply gas. A vapor deposition film of an inorganic oxide such as silicon oxide can be formed by using a low temperature plasma chemical vapor deposition method using oxygen gas or the like and using a low temperature plasma generator or the like. In the above, as the low-temperature plasma generator, for example, generators such as high-frequency plasma, pulse wave plasma, and microwave plasma can be used. It is desirable to use a generator according to

  An example of the formation method of the vapor-deposited film of the inorganic oxide by the low-temperature plasma chemical vapor deposition method will be specifically described with reference to an example. FIG. 4 is a schematic configuration diagram of a low-temperature plasma chemical vapor deposition apparatus showing an outline of a method for forming a deposited film of an inorganic oxide by the plasma chemical vapor deposition method. As shown in FIG. 4, in the present invention, the base film 101 is unwound from the unwinding roll 43 disposed in the vacuum chamber 42 of the plasma chemical vapor deposition apparatus 41, and the base film 101 is supported as an auxiliary material. It is conveyed onto the circumferential surface of the cooling / electrode drum 45 at a predetermined speed via the roll 44. Next, vapor deposition monomer gas such as oxygen gas, inert gas, organosilicon compound, etc. is supplied from gas supply devices 46, 47 and raw material volatilization supply device 48, etc., and a mixed gas composition for vapor deposition composed of these is prepared. Then, the vapor deposition mixed gas composition is introduced into the vacuum chamber 42 through the raw material supply nozzle 49. Then, plasma is generated by the glow discharge plasma 50 on the substrate film 101 conveyed on the peripheral surface of the cooling / electrode drum 45, and irradiated with this to deposit a vapor deposited film of an inorganic oxide such as silicon oxide. To form a film. At this time, a predetermined power is applied to the cooling / electrode drum 45 from a power source 51 disposed outside the chamber, and a magnet 52 is disposed in the vicinity of the cooling / electrode drum 45. Plasma generation is promoted. Next, the base film 101 on which a deposited film of an inorganic oxide such as silicon oxide is formed is wound on a winding roll 54 via an auxiliary roll 53, so that inorganic oxidation by plasma chemical vapor deposition according to the present invention is performed. A vapor-deposited film of a product can be manufactured. In the figure, reference numeral 55 represents a vacuum pump.

  The above exemplification shows an example of a method for forming a vapor-deposited film of an inorganic oxide by plasma enhanced chemical vapor deposition, and it goes without saying that the present invention is not limited thereby. Although not shown, in the present invention, the inorganic oxide vapor-deposited film may be used not only in one layer of the vapor-deposited film but also in a multilayer film state in which two or more layers are laminated. It is also possible to form an inorganic oxide vapor-deposited film that is used as a seed or a mixture of two or more kinds and mixed with different materials. In the present invention, the first layer of an inorganic oxide vapor deposition film is first formed using the low temperature plasma chemical vapor deposition apparatus as described above, and then the inorganic oxide vapor deposition is performed in the same manner. An inorganic oxide vapor deposition film is further formed on the film, or these are connected in series using the low temperature plasma chemical vapor deposition apparatus as described above, and the inorganic oxide vapor deposition is continuously performed. By forming a film, it is also possible to form an inorganic oxide vapor-deposited film composed of two or more multilayer films.

In the above, the inside of the vacuum chamber is depressurized by a vacuum pump and adjusted to a vacuum degree of 1 × 10 ⁻¹ to 1 × 10 ⁻⁸ Torr, preferably a vacuum degree of 1 × 10 ⁻³ to 1 × 10 ⁻⁷ Torr. It is desirable to do. The raw material volatilization supply device volatilizes the organic silicon compound as the raw material and mixes it with oxygen gas or inert gas supplied from the gas supply device, and this mixed gas is introduced into the vacuum chamber via the raw material supply nozzle. It is to be introduced. In this case, the content of the organosilicon compound in the mixed gas is about 1 to 40%, the oxygen gas content is about 10 to 70%, and the inert gas content is about 10 to 60%. For example, the mixing ratio of the organosilicon compound, oxygen gas, and inert gas can be about 1: 1: 1 to 1:20:10. On the other hand, since a predetermined voltage is applied to the cooling / electrode drum from the power source, glow discharge plasma is generated in the vicinity of the opening of the raw material supply nozzle in the vacuum chamber and the cooling / electrode drum. The plasma is derived from one or more gas components in the mixed gas. In this state, the resin film is transported at a constant speed, so that the glow discharge plasma causes the resin on the cooling / electrode drum peripheral surface. A vapor-deposited film of an inorganic oxide such as silicon oxide can be formed on the film. At this time, the degree of vacuum in the vacuum chamber can be adjusted within the range of 1 × 10 ⁻¹ to 1 × 10 ⁻⁴ Torr, preferably in the range of 1 × 10 ⁻¹ to 1 × 10 ⁻² Torr. Desirably, the conveyance speed of the resin film is adjusted to 10 to 300 m / min, preferably 50 to 150 m / min.

Further, formed in the plasma chemical vapor deposition apparatus, the deposition film of an inorganic oxide such as silicon oxide, on a resin film, a thin film in the form of SiO _X while the plasma raw material gas is oxidized with oxygen gas Therefore, the vapor-deposited film of inorganic oxide such as silicon oxide formed thereby is a dense continuous layer with few gaps and high flexibility. Accordingly, inorganic oxide such as silicon oxide is formed. The barrier property of the deposited film is much higher than that of an inorganic oxide deposited film such as silicon oxide formed by a conventional vacuum deposition method or the like, and a sufficient barrier property can be obtained with a thin film thickness. It will be possible. Further, in the present invention, the surface of the resin film is cleaned by plasma, and polar groups, free radicals, etc. are generated on the surface of the resin film. Therefore, a deposited film of inorganic oxide such as silicon oxide and the resin film are formed. It has the advantage that it becomes a thing with high close adhesiveness. Furthermore, as described above, the degree of vacuum when forming a continuous film of an inorganic oxide such as silicon oxide is 1 × 10 ⁻¹ to 1 × 10 ⁻⁴ Torr, preferably 1 × 10 ⁻¹ to 1 × 10 ^−. Compared with 1 × 10 ⁻⁴ to 1 × 10 ⁻⁵ Torr, which is a vacuum degree when forming a deposited film of an inorganic oxide such as silicon oxide by a conventional vacuum deposition method, adjusted within the range of ² Torr Since the degree of vacuum is low, it is possible to shorten the time for setting the vacuum state at the time of replacing the original film of the resin film, it is easy to stabilize the degree of vacuum, and the film forming process is stabilized.

In the present invention, a vapor deposition film of silicon oxide formed using a vapor deposition monomer gas such as an organosilicon compound chemically reacts with a vapor deposition monomer gas such as an organosilicon compound and oxygen gas, and the reaction product is a resin. The film is tightly bonded to one surface of the film to form a dense, flexible thin film, and is usually represented by the general formula SiO _X (where X represents a number from 0 to 2). It is a continuous thin film mainly composed of silicon oxide. As the deposition film of the silicon oxide, transparency, from the viewpoint of the barrier property and the like, the general formula SiO X _(where, X represents the number of 1.3 to 1.9) of silicon oxide represented by A thin film mainly composed of a deposited film is preferable. In the above, the value of X varies depending on the molar ratio of vapor deposition monomer gas to oxygen gas, plasma energy, etc. Generally, the gas permeability decreases as the value of X decreases, but the film itself Yellowish and less transparent.

In addition, the silicon oxide vapor-deposited film is mainly composed of silicon oxide, and further, at least one kind of compound composed of one kind of carbon, hydrogen, silicon, or oxygen, or two or more kinds thereof is chemically used. It consists of a deposited film that is contained by bonding or the like. For example, when a compound having a C—H bond, a compound having a Si—H bond, or a carbon unit is in the form of graphite, diamond, fullerene, or the like, an organic silicon compound as a raw material or a derivative thereof is further added. It may be contained by a chemical bond or the like. Specific examples include hydrocarbons having a CH ₃ site, hydrosilica such as SiH ₃ silyl, SiH ₂ silylene, and hydroxyl derivatives such as SiH ₂ OH silanol. In addition to the above, the type, amount, etc. of the compound contained in the deposited film of silicon oxide can be changed by changing the conditions of the vapor deposition process. In the present invention, the content of the above-mentioned compound in the deposited silicon oxide film is preferably 0.1 to 50%, particularly about 5 to 20%. If this content is less than 0.1%, the impact resistance, spreadability, flexibility, etc. of the deposited silicon oxide film become insufficient, and scratches, cracks, etc. are likely to occur due to bending, and a high barrier. On the other hand, if it exceeds 50%, the barrier property is lowered, which is not preferable. Furthermore, in the present invention, in the silicon oxide vapor deposition film, the content of the above compound is preferably decreased from the surface of the silicon oxide vapor deposition film in the depth direction. On the surface of the deposited film, impact resistance and the like can be enhanced by the above-mentioned compound, etc. On the other hand, since the content of the above-mentioned compound is small at the interface with the resin film, vapor deposition of the resin film and silicon oxide is performed. It has the advantage that the tight adhesion to the film is strong.

  In the present invention, for example, a surface analyzer such as an X-ray photoelectron spectrometer (Xray Photoelectron Spectroscopy (XPS)) or a secondary ion mass spectrometer (Secondary Ion Mass Spectroscopy (SIMS)) is used to perform ionization in the depth direction. The physical properties as described above can be confirmed by performing elemental analysis of the deposited film of silicon oxide using a method of analysis by etching or the like. In the present invention, as described above, the thickness of the silicon oxide vapor-deposited film is preferably in the range of 50 to 4000 mm, more preferably in the range of 100 to 1000 mm. If the film thickness is greater than 1000 mm, or even 4000 mm, cracks or the like are likely to occur in the film, which is not preferable. If the film thickness is less than 100 mm, or even less than 50 mm, it is difficult to achieve a barrier effect. That is not preferable. This film thickness can be measured by a fundamental parameter method using, for example, a fluorescent X-ray analyzer (model name, RIX2000 type) manufactured by Rigaku Corporation. The film thickness can also be directly measured by observing a slice of the thin film with a transmission electron microscope (TEM), for example. As a simpler and faster measurement method, samples with a clear thickness obtained by TEM are used, and X-rays of Si elements of these samples using a fluorescent X-ray analyzer (model name, RIX2000 type) manufactured by Rigaku Corporation. The thickness can be measured more easily by measuring the strength and obtaining a calibration curve from the measured film thickness of the TEM. Further, in the above, as means for changing the film thickness of the silicon oxide vapor deposition film, the volume velocity of the vapor deposition film is increased, that is, the method of increasing the amount of monomer gas and oxygen gas, and the vapor deposition rate. The method of making it late can be mentioned.

  Next, in the above, as a monomer gas for vapor deposition of an organic silicon compound or the like for forming a vapor deposition film of an inorganic oxide such as silicon oxide, for example, 1.1.3.3-tetramethyldisiloxane, hexamethyldisiloxane , Vinyltrimethylsilane, methyltrimethylsilane, hexamethyldisilane, methylsilane, dimethylsilane, trimethylsilane, diethylsilane, propylsilane, phenylsilane, vinyltriethoxysilane, vinyltrimethoxysilane, tetramethoxysilane, tetraethoxysilane, phenyltri Methoxysilane, methyltriethoxysilane, octamethylcyclotetrasiloxane and the like can be used. In the present invention, among the organic silicon compounds as described above, the use of 1.1.3.3-tetramethyldisiloxane or hexamethyldisiloxane as a raw material is easy to handle and formed continuous film. From the characteristics of the above, it is particularly preferable. Moreover, in the above, as an inert gas, argon gas, helium gas, etc. can be used, for example.

  In the present invention, the inorganic oxide vapor-deposited film includes, for example, two or more layers of different inorganic oxide vapor-deposited films using both physical vapor deposition and chemical vapor deposition. It can also be used by forming a composite film. In this case, as a composite film composed of two or more layers of different types of inorganic oxide vapor-deposited films, for example, first, on a base film, a chemical vapor deposition method is used to provide a dense, flexible, and cracked film. An inorganic oxide vapor deposition film capable of relatively preventing generation is provided, and then an inorganic oxide vapor deposition film formed by physical vapor deposition is provided on the inorganic oxide vapor deposition film to form a composite of two or more layers. It is desirable to form a vapor-deposited film of inorganic oxide consisting of a film. Of course, in the present invention, contrary to the above, an inorganic oxide vapor deposition film is first provided on the substrate film by physical vapor deposition, and then dense by chemical vapor deposition. An inorganic oxide vapor-deposited film composed of two or more composite films may be formed by providing an inorganic oxide vapor-deposited film that is highly flexible and can relatively prevent the occurrence of cracks.

Furthermore, in the back surface protective sheet of the present invention, the gas barrier coating film 3 is further formed on the surface of the base polyester resin film 4 on which the inorganic oxide vapor-deposited film 2 is formed. Give. In the present invention, in order to provide good water vapor barrier properties, it is necessary to form at least one layer of the inorganic oxide vapor-deposited film 2 and the gas barrier coating film 3 respectively. The gas barrier coating film 3 in the present invention has the following general formula:
R ¹ _n M (OR ² ) _m
(Wherein R ¹ and R ² each independently represents an organic group having 1 to 8 carbon atoms, M represents a metal atom, n represents an integer of 0 or more, m represents an integer of 1 or more, and n + m) Represents at least one alkoxide represented by the valence of M), a polyvinyl alcohol resin and / or an ethylene / vinyl alcohol copolymer, a sol-gel catalyst, acid, water and organic It can consist of a gas barrier composition obtained by polycondensation by a sol-gel method in the presence of a solvent. Specifically, the gas barrier composition is applied on the surface of the base polyester resin film on which the inorganic oxide vapor-deposited film is formed to provide a coating film, and then at 20 ° C. to 180 ° C. and A gas barrier laminate having an inorganic oxide vapor deposition film 2 and a gas barrier coating film 3 sequentially on a base polyester resin film 4 by heat treatment at a temperature below the melting point of the resin film for 10 seconds to 10 minutes. A film can be obtained.

  In the present invention, the gas barrier coating film 3 is formed by repeatedly applying the gas barrier composition and stacking two or more coating films, and then heat-treating in the same manner as described above, thereby performing the inorganic oxidation. You may form as a composite polymer layer which laminated | stacked two or more layers on the vapor deposition film of the thing.

  In the present invention, as the alkoxide represented by the above general formula, at least one of a partial hydrolyzate of alkoxide and a hydrolyzed condensate of alkoxide can be used. Moreover, as a partial hydrolyzate of alkoxide, it is not necessary that all alkoxy groups are hydrolyzed, and one or more hydrolyzed ones or a mixture thereof may be used. Furthermore, as a condensate of hydrolysis, a dimer or more of a partially hydrolyzed alkoxide, specifically, a 2 to 6 mer can be used.

  In the alkoxide represented by the above general formula, silicon, zirconium, titanium, aluminum and the like can be used as the metal atom represented by M, and as a preferred metal in the present invention, for example, silicon is cited. be able to. In the present invention, the alkoxide may be used alone or in combination of two or more different metal atoms in the same solution.

In the alkoxide represented by the above general formula, specific examples of the organic group represented by R ¹ include, for example, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i Examples thereof include alkyl groups such as -butyl group, sec-butyl group, t-butyl group, n-hexyl group and n-octyl group. In the alkoxide represented by the above general formula, specific examples of the organic group represented by R ² include, for example, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, sec -A butyl group etc. can be mentioned. In the present invention, these alkyl groups in the same molecule may be the same or different.

In the present invention, as the alkoxide represented by the above general formula, for example, alkoxysilane in which M is Si is preferably used. Such alkoxysilane is represented by the general formula Si (ORa) ₄ (wherein Ra represents a lower alkyl group). In the above, examples of Ra include a methyl group, an ethyl group, an n-propyl group, and an n-butyl group. Specific examples of the alkoxysilane include, for example, tetramethoxysilane Si (OCH ₃ ) ₄ , tetraethoxysilane Si (OC ₂ H ₅ ) ₄ , tetrapropoxysilane Si (OC ₃ H ₇ ) ₄ , tetrabutoxysilane. Si _{(OC 4} H ₉₎ can be given ₄ or the like.

In the present invention, examples of the alkoxide represented by the above general formula include, for example, the general formula Rb _n Si (ORc) _4-m (wherein, n represents an integer of 0 or more, and m represents 1, 2 or more). And an alkylalkoxysilane represented by Rb and Rc represents a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and the like. Specific examples of the alkylalkoxysilane include, for example, methyltrimethoxysilane CH ₃ Si (OCH ₃ ) ₃ , methyltriethoxysilane CH ₃ Si (OC ₂ H ₅ ) ₃ , dimethyldimethoxysilane (CH ₃ ) ₂ Si ( OCH _{3) 2,} dimethyl diethoxy silane _{(CH 3) 2 Si (OC} 2 H 5) can be used ₂ or the like. Said alkoxysilane, alkylalkoxysilane, etc. can be used individually or in mixture of 2 or more types. In the present invention, a polycondensation product of the above alkoxysilane can also be used, and specifically, for example, polytetramethoxysilane, polytetraemethoxysilane, and the like can be used.

Furthermore, in the present invention, as the alkoxide represented by the above general formula, for example, a zirconium alkoxide in which M is Zr can be used. Specific examples of the zirconium alkoxide include, for example, tetramethoxyzirconium Zr (OCH ₃ ) ₄ , tetraethoxyzirconium Zr (OC ₂ H ₅ ) ₄ , tetra ipropoxyzirconium Zr (isO—OC ₃ H ₇ ) ₄ , tetra n Butoxyzirconium Zr (OC ₄ H ₉ ) ₄ or the like can be used.

Furthermore, in the present invention, as the alkoxide represented by the above general formula, for example, a titanium alkoxide in which M is Ti can be used. Specific examples of the titanium alkoxide include, for example, tetramethoxytitanium Ti (OCH ₃ ) ₄ , tetraethoxytitanium Ti (OC ₂ H ₅ ) ₄ , tetraisopropoxytitanium Ti (isO—OC ₃ H ₇ ) ₄ , tetra n-butoxy titanium Ti (OC ₄ H ₉ ) ₄ or the like can be used.

Furthermore, in the present invention, as the alkoxide represented by the above general formula, for example, an aluminum alkoxide in which M is Al can be used. Specific examples of the aluminum alkoxide include, for example, tetramethoxyaluminum Al (OCH ₃ ) ₄ , tetraethoxyaluminum Al (OC ₂ H ₅ ) ₄ , tetraisopropoxyaluminum Al (isO—OC ₃ H ₇ ) ₄ , tetra n-butoxy aluminum Al (OC ₄ H ₉ ) ₄ or the like can be used.

  In the present invention, the above alkoxides can be used in combination of two or more thereof. Particularly in the present invention, the toughness, heat resistance, etc. of the obtained gas barrier laminate film can be improved by using a mixture of alkoxysilane and zirconium alkoxide. In this case, the amount of zirconium alkoxide used is in the range of 10 parts by mass or less, preferably about 5 parts by mass with respect to 100 parts by mass of alkoxysilane. When the amount used exceeds 10 parts by mass, the formed gas barrier coating film is easily gelled, and the brittleness of the film is increased, and the gas barrier coating film is easily peeled off when the resin film is coated. It becomes a trend.

  In the present invention, in particular, by using a mixture of alkoxysilane and titanium alkoxide, there is an advantage that the heat conductivity of the obtained gas barrier coating film is lowered and the heat resistance of the gas barrier laminated film is remarkably improved. is there. In this case, the amount of titanium alkoxide used is in the range of 5 parts by mass or less, preferably about 3 parts by mass with respect to 100 parts by mass of alkoxysilane. When the amount used exceeds 5 parts by mass, the brittleness of the formed gas barrier coating film increases, and when the base film is coated, the gas barrier coating film tends to be easily peeled off.

  Next, as the polyvinyl alcohol resin and / or ethylene / vinyl alcohol copolymer forming the gas barrier coating film, a polyvinyl alcohol resin or an ethylene / vinyl alcohol copolymer may be used alone. Alternatively, a polyvinyl alcohol-based resin and an ethylene / vinyl alcohol copolymer can be used in combination. In the present invention, by using a polyvinyl alcohol resin and / or an ethylene / vinyl alcohol copolymer, physical properties such as gas barrier properties, water resistance and weather resistance of the gas barrier coating film can be remarkably improved. In particular, in the present invention, by using a combination of a polyvinyl alcohol-based resin and an ethylene / vinyl alcohol copolymer, in addition to the above physical properties such as gas barrier properties, water resistance and weather resistance, hot water resistance and hot water A gas barrier coating film remarkably excellent in gas barrier properties after the treatment can be formed.

  In the present invention, when a polyvinyl alcohol-based resin and an ethylene / vinyl alcohol copolymer are used in combination, the blending ratio thereof is, as a weight ratio, polyvinyl alcohol-based resin: ethylene / vinyl alcohol copolymer = 10: The ratio is preferably about 0.05 to 10: 6, and more preferably about 10: 1.

  In the present invention, the content of the polyvinyl alcohol-based resin and / or the ethylene / vinyl alcohol copolymer is in the range of 5 to 500 parts by mass with respect to 100 parts by mass of the total alkoxide, preferably about It is preferable to prepare the gas barrier composition at a blending ratio of 20 to 200 parts by mass. When the content exceeds 500 parts by mass, the brittleness of the gas barrier coating film is increased, which is not preferable because the water resistance and weather resistance of the obtained gas barrier laminated film tend to be lowered. If it is less than 1, it is not preferable because the gas barrier property is lowered.

  In the present invention, as the polyvinyl alcohol-based resin, those obtained by saponifying polyvinyl acetate can be generally used. The polyvinyl alcohol resin may be a partially saponified polyvinyl alcohol resin in which several tens of percent of acetate groups remain, a completely saponified polyvinyl alcohol in which no acetate groups remain, or a modified polyvinyl alcohol in which OH groups have been modified. A resin may be used and is not particularly limited. Specific examples of such a polyvinyl alcohol resin include RS-110 (saponification degree = 99%, polymerization degree = 1,000), an RS polymer manufactured by Kuraray Co., Ltd., and Kuraray Poval LM-20SO (saponification) manufactured by the same company. Degree = 40%, polymerization degree = 2,000), GOHSENOL NM-14 manufactured by Nippon Synthetic Chemical Industry Co., Ltd. (degree of saponification = 99%, degree of polymerization = 1,400), and the like.

  In the present invention, as the ethylene-vinyl alcohol copolymer, a saponified product of a copolymer of ethylene and vinyl acetate, that is, a product obtained by saponifying an ethylene-vinyl acetate random copolymer should be used. Can do. Specifically, it includes a partial saponification product in which several tens mol% of acetic acid groups remain to a complete saponification product in which only several mol% of acetic acid groups remain or no acetic acid group remains. Although it is not a thing, the preferable saponification degree from a gas-barrier viewpoint is 80 mol% or more, More preferably, it is 90 mol% or more, More preferably, it is 95 mol% or more. In addition, the content of the repeating unit derived from ethylene in the ethylene / vinyl alcohol copolymer (hereinafter also referred to as “ethylene content”) is usually 0 to 50 mol%, preferably 20 to 45 mol%. Is used. Specific examples of such an ethylene / vinyl alcohol copolymer include Kuraray Co., Ltd., Eval EP-F101 (ethylene content: 32 mol%), Nippon Synthetic Chemical Industry Co., Ltd., Soarnol D2908 (ethylene content: 29 mol%). Etc.

  Next, when preparing the gas barrier composition, in addition to the above components, for example, a silane coupling agent or the like can also be added. As such a silane coupling agent, a known organic reactive group-containing organoalkoxysilane can be used. Among them, in the present invention, an organoalkoxysilane having an epoxy group is particularly suitable. For example, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, or β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane or the like can be used. These silane coupling agents may be used alone or in combination of two or more. In this invention, the usage-amount of a silane coupling agent exists in the range of 1-20 mass parts suitably with respect to 100 mass parts of alkoxysilanes. When the amount of the silane coupling agent used exceeds 20 parts by mass, the gas barrier coating film to be formed tends to have increased rigidity and brittleness, and the insulating property and workability of the gas barrier coating film tend to decrease. It is not preferable.

  Next, as a sol-gel method catalyst used in the above gas barrier composition, mainly a polycondensation catalyst, a tertiary amine that is substantially insoluble in water and soluble in an organic solvent is used. Specifically, for example, N, N-dimethylbenzylamine, tripropylamine, tributylamine, tripentylamine and the like can be used. In the present invention, N, N-dimethylbenzylamine is particularly preferred. The amount used is 0.01 to 1.0 part by mass, preferably about 0.03 part by mass, per 100 parts by mass of the total amount of alkoxide and silane coupling agent.

  The acid used in the gas barrier composition is used as a catalyst for the sol-gel method, mainly as a catalyst for hydrolysis of an alkoxide, a silane coupling agent, or the like. Examples of the acid include mineral acids such as sulfuric acid, hydrochloric acid, and nitric acid, and organic acids such as acetic acid and tartaric acid. The amount of the acid used is 0.001 to 0.05 mol, particularly about 0.01 mol, based on the total molar amount of the alkoxide and the alkoxide content of the silane coupling agent (for example, silicate moiety). Is preferred.

  Furthermore, in said gas-barrier composition, 0.1-100 mol with respect to 1 mol of total molar amounts of the said alkoxide, Preferably 0.8-2 mol of water can be used. When the amount of water exceeds 2 mol, the polymer obtained from the alkoxysilane and the metal alkoxide becomes spherical particles, and the spherical particles are three-dimensionally crosslinked to form a porous polymer having a low density. However, such a porous polymer is not preferable because the gas barrier property of the gas barrier laminate film cannot be improved. Moreover, when the amount of water is less than 0.8 mol, it is not preferable because the hydrolysis reaction tends to hardly proceed.

  Furthermore, as an organic solvent used in the gas barrier composition, for example, methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butanol and the like can be used. In the gas barrier composition, the polyvinyl alcohol-based resin and / or the ethylene / vinyl alcohol copolymer is preferably in a state of being dissolved in a coating solution containing the alkoxide, the silane coupling agent, or the like. Therefore, the type of the organic solvent is appropriately selected. When a polyvinyl alcohol resin and an ethylene / vinyl alcohol copolymer are used in combination, n-butanol is preferably used as the organic solvent. In the present invention, as the ethylene / vinyl alcohol copolymer solubilized in a solvent, for example, those commercially available as Soarnol (trade name) can be used. The amount of the organic solvent used is usually 100 parts by mass of the total amount of the alkoxide, silane coupling agent, polyvinyl alcohol resin and / or ethylene / vinyl alcohol copolymer, acid and sol-gel method catalyst. It is in the range of 30 to 500 parts by mass per unit.

  Specifically, the gas barrier coating film according to the present invention is produced, for example, as follows. First, an alkoxide such as alkoxysilane, a silane coupling agent, a polyvinyl alcohol resin and / or an ethylene / vinyl alcohol copolymer, a sol-gel method catalyst, an acid, water, an organic solvent, and, if necessary, A metal alkoxide or the like is mixed to prepare a gas barrier composition (coating liquid). At this time, a polycondensation reaction gradually proceeds in the gas barrier composition (coating liquid).

  Next, the above gas barrier composition (coating liquid) is applied by an ordinary method on the inorganic oxide vapor-deposited film formed on one surface of the resin film and dried. By this drying, polycondensation of the alkoxide such as alkoxysilane, metal alkoxide, silane coupling agent, and polyvinyl alcohol resin and / or ethylene / vinyl alcohol copolymer proceeds to form a coating film. The Further, if desired, the above coating operation is repeated to laminate a plurality of coating films composed of two or more layers.

  Finally, the resin film coated with the coating solution is heated at a temperature of 20 ° C. to 180 ° C. and lower than the melting point of the resin film, preferably about 50 ° C. to 160 ° C. One or more gas barrier coating films of the above gas barrier composition (coating liquid) are formed on the inorganic oxide vapor-deposited film formed on one surface of the base film by heat treatment for 10 minutes. Form. The gas barrier coating film according to the present invention thus obtained is excellent in gas barrier properties.

  In the present invention, in place of the polyvinyl alcohol resin, an ethylene / vinyl alcohol copolymer, or both a polyvinyl alcohol resin and an ethylene / vinyl alcohol copolymer are used in the same manner as described above. The gas barrier coating film according to the present invention produced by performing drying and heat treatment has an advantage that the gas barrier property after hot water treatment such as boil treatment and retort treatment is further improved.

  Furthermore, in the present invention, when the ethylene / vinyl alcohol copolymer or the combination of the polyvinyl alcohol resin and the ethylene / vinyl alcohol copolymer is not used as described above, that is, only the polyvinyl alcohol resin is used. In the case of producing the gas barrier coating film according to the present invention, in order to improve the gas barrier property after the hot water treatment, for example, a gas barrier composition using a polyvinyl alcohol resin is applied in advance. Forming a first coating layer, and then coating a gas barrier composition containing an ethylene / vinyl alcohol copolymer on the coating layer to form a second coating layer, By forming these composite layers, it is also possible to improve the gas barrier properties of the gas barrier coating film according to the present invention.

  Furthermore, the coating layer formed by the gas barrier composition containing the above-mentioned ethylene / vinyl alcohol copolymer, or the gas barrier composition containing a combination of a polyvinyl alcohol-based resin and an ethylene / vinyl alcohol copolymer. Forming a plurality of coating layers formed of an object as a plurality of layers is also an effective means for improving the gas barrier properties of the gas barrier coating film according to the present invention.

  Next, the operation of the method for producing a gas barrier coating film according to the present invention will be described by using an alkoxysilane as an alkoxide. First, the alkoxysilane and the metal alkoxide are hydrolyzed by the added water. At that time, the acid serves as a catalyst for hydrolysis. Next, protons are taken from the generated hydroxyl groups by the action of the sol-gel method catalyst, and hydrolyzed products are dehydrated and polycondensed. At this time, the silane coupling agent is simultaneously hydrolyzed by the acid catalyst, and the alkoxy group becomes a hydroxyl group. In addition, due to the action of the base catalyst, ring opening of the epoxy group also occurs and a hydroxyl group is generated. A polycondensation reaction between the hydrolyzed silane coupling agent and the hydrolyzed alkoxide also proceeds. Further, since the reaction system includes a polyvinyl alcohol resin, an ethylene / vinyl alcohol copolymer, or a polyvinyl alcohol resin and an ethylene / vinyl alcohol copolymer, the polyvinyl alcohol resin and the ethylene / vinyl alcohol copolymer are present. Reaction with the hydroxyl group possessed also occurs. The polycondensate produced is, for example, a composite polymer containing an inorganic part composed of a bond such as Si-O-Si, Si-O-Zr, Si-O-Ti, and an organic part derived from a silane coupling agent. Configure.

  In the above reaction, for example, a linear polymer having a partial structural formula represented by the following formula (III) and further having a portion derived from a silane coupling agent is first generated. This polymer has an OR group (an alkoxy group such as an ethoxy group) branched from a linear polymer. The OR group is hydrolyzed to become an OH group using an existing acid as a catalyst, and the OH group is first deprotonated by the action of a sol-gel method catalyst (base catalyst), and then polycondensation proceeds. . That is, this OH group undergoes a polycondensation reaction with a polyvinyl alcohol-based resin represented by the following formula (I) or an ethylene / vinyl alcohol copolymer represented by the following formula (II) to form Si—O—Si. For example, it is considered that a composite polymer represented by the following formula (IV) or a copolymerized composite polymer represented by the following formulas (V) and (VI) is formed.

  The above reaction proceeds at room temperature, and the viscosity of the gas barrier composition (coating liquid) increases during preparation. When this gas barrier composition (coating liquid) is applied onto an inorganic oxide vapor-deposited film provided on one surface of a resin film and heated to remove the solvent and the alcohol produced by the polycondensation reaction, The condensation reaction is completed, and a transparent coating layer is formed on the inorganic oxide vapor deposition film provided on one surface of the base film. When a plurality of coating layers are laminated, the composite polymers in the interlayer coating layers are also condensed, and the layers are firmly bonded to each other. Furthermore, since the organic reactive group of the silane coupling agent and the hydroxyl group generated by hydrolysis are bonded to the hydroxyl group on the surface of the inorganic oxide vapor deposition film provided on one surface of the resin film, one of the resin films Adhesiveness, adhesiveness, etc. between the surface of the vapor-deposited inorganic oxide film provided on the surface and the coating layer are also good.

  In the above method, since the amount of water added is adjusted to 0.8 to 2 mol, preferably 1.5 mol, relative to 1 mol of the alkoxide, the above linear polymer is formed. The Such a linear polymer has crystallinity and has a structure in which a large number of minute crystals are embedded in an amorphous part. Such a crystal structure is the same as that of a crystalline organic polymer (for example, vinylidene chloride or polyvinyl alcohol). Furthermore, a polar group (OH group) is partially present in the molecule, and the molecular aggregation energy is high. Because of its high rigidity, it exhibits good gas barrier properties.

  In the present invention, the inorganic oxide vapor-deposited film and the gas barrier coating film form, for example, a chemical bond, a hydrogen bond, or a coordinate bond by hydrolysis / co-condensation reaction, and the like. And the gas barrier coating film can be improved, and a synergistic effect of the two layers can provide a better gas barrier effect. Examples of the method for applying the gas barrier composition of the present invention include, for example, once by a roll coater such as a gravure roll coater, spray coat, spin coat, dipping, brush, barcode, applicator or the like. A coating film having a dry film thickness of 0.01 to 30 μm, preferably 0.1 to 10 μm can be formed by a plurality of times of application, and further, 50 to 300 ° C., preferably 70 to 70 ° C. under a normal environment. Condensation is performed by heating and drying at a temperature of 200 ° C. for 0.005 to 60 minutes, preferably 0.01 to 10 minutes, and the gas barrier coating film of the present invention can be formed. Further, if necessary, when applying the gas barrier composition of the present invention, a primer agent or the like can be applied on the inorganic oxide vapor-deposited film in advance, or corona discharge treatment or plasma treatment. It is also possible to arbitrarily perform a pretreatment such as the above.

  In the present invention, the base polyester resin film 4 provided with the inorganic oxide vapor-deposited film 2 may be provided in a layered manner. In this case, in the resin film provided with the inorganic oxide vapor deposition film on one surface, the surfaces provided with the inorganic oxide vapor deposition film, the surfaces not provided with the inorganic oxide vapor deposition film, or the inorganic oxide vapor deposition film The layers may be stacked so as to face each other in any combination of the surface provided with the vapor deposition film and the surface not provided with the inorganic oxide vapor deposition film. In addition, as the multi-layer system, a dry laminate laminating system for laminating via a laminating adhesive layer, which will be described later, or a melt extrusion laminating for laminating via an adhesion aid layer using an anchor coating agent, a melt-extruded resin layer, etc. Any lamination method such as a method may be used. Furthermore, in this invention, a back surface protection sheet can also be manufactured combining the said dry laminate lamination system and a melt extrusion lamination system, for example. In this case, on the surface of the inorganic oxide vapor-deposited film, for example, a pretreatment such as plasma treatment or corona treatment, or a primer agent layer or a desired resin layer is provided in order to improve the tight adhesion of the laminate. Arbitrary provision is also possible.

  In the present invention, when the base polyester resin film 4 provided with the inorganic oxide vapor deposition film 2 is laminated, a tough resin film may be interposed therebetween. To laminate two or more resin films provided with an inorganic oxide vapor-deposited film via a tough resin film, a dry laminate lamination method in which the layers are laminated via the laminating adhesive layer as described above, Alternatively, any lamination method such as an adhesion assistant layer using an anchor coating agent or the like, a melt extrusion lamination method in which the layers are laminated via a melt extrusion resin layer, etc. may be used. Any one of a surface provided with a film, a surface not provided, and a surface of a tough resin film may be combined and faced to overlap each other.

  As the tough resin film, the strength, rigidity, waist, etc. of the solar cell module itself are maintained, and strength deterioration due to hydrolysis caused by moisture entering the solar cell module, etc., or constitutes the solar cell module It has excellent properties in mechanical, physical, chemical, etc., because it prevents strength deterioration due to degassing such as vinyl acetate gas generated by decomposition of the filler layer Excellent strength, weather resistance, heat resistance, water resistance, light resistance, wind pressure resistance, drought resistance, chemical resistance, moisture resistance, and other properties, especially preventing moisture and oxygen from entering. A tough resin film or sheet that significantly improves moisture resistance, minimizes long-term performance degradation, prevents hydrolysis degradation, etc., is extremely durable, and has excellent protection capabilities. Use It can be. Specifically, for example, a film or sheet of a tough resin such as a polyester resin, a polyamide resin, a polyaramid resin, a polypropylene resin, a polycarbonate resin, a polyacetal resin, a polystyrene resin, or a fluorine resin is used. Can do. As the resin film or sheet, any of an unstretched film or a stretched film stretched in a uniaxial direction or a biaxial direction can be used. Among them, in the present invention, a two-stretched polyethylene terephthalate film or a polypropylene resin film is preferably used as the tough resin film. Further, in the present invention, the thickness of the tough resin film may be a minimum thickness necessary for maintaining strength, rigidity, waist, etc. If it is too thick, there is a disadvantage that the cost increases. On the contrary, if it is too thin, the strength, rigidity, waist and the like are lowered, which is not preferable. In the present invention, for the reasons described above, the thickness is most preferably in the range of 10 μm to 200 μm, particularly in the range of 30 μm to 100 μm.

(Synthetic resin film)
Next, as the synthetic resin film 5 used in the present invention, an olefin resin that is excellent in weather resistance and inexpensive, for example, a resin film mainly composed of a polypropylene resin and a polyethylene resin can be used. More preferably, a resin film containing a polypropylene resin as a main component is used.

  As such polypropylene resin, a homopolymer of propylene which is a by-product generated when ethylene is produced by pyrolysis of petroleum hydrocarbon, or other monomers such as propylene and α-olefin, etc. Copolymers can be used. In the present invention, as the polypropylene resin, specifically, when a cationic polymerization catalyst or the like is used when polymerizing propylene, a low molecular weight polymer is obtained. When a Natta catalyst is used, an isotactic polymer having a high molecular weight and high crystallinity can be obtained, and it is preferable to use this isotactic polymer. Such an isotactic polymer has a melting point of about 164 to 170 ° C., a specific gravity of about 0.90 to 0.91, and a molecular weight of about 100,000 to 200,000, and its properties are largely controlled by its crystallinity. A high polymer has excellent tensile strength and impact strength, has good heat resistance and bending fatigue strength, and has very good workability.

  Moreover, in this invention, when using the said polypropylene resin for the synthetic resin film 5, as needed, resin which has compatibility with polypropylene resins, such as a polyethylene resin, for example, is arbitrarily set as a polypropylene resin. It may be added and modified. In the present invention, by using such a modified polypropylene-based resin, when manufacturing a solar cell module, it is excellent in close adhesion with a filler layer and the like, and further prevents intrusion of moisture, oxygen, etc. Significantly improves the moisture resistance, minimizes long-term performance degradation, especially prevents hydrolysis degradation, is extremely durable, has excellent protection capability, and is safer at lower cost A solar cell module can be configured. In particular, when a transparent polypropylene resin film to which no colorant is added is used as the synthetic resin film, it is preferable to use a polypropylene resin that is not easily whitened by bending.

  In the present invention, the synthetic resin film 5 needs to be provided in at least one layer, and may be two or more layers. In addition, when providing the synthetic resin film 5 by two or more layers, in order to acquire two effects, the fall suppression of a light reflectivity, and maintenance of mechanical strength, a rutile type titanium oxide has one surface of a back surface protection sheet. It is necessary to be included in the outer synthetic resin film. When the synthetic resin film 5 has two or more layers, even if the inner synthetic resin film contains rutile titanium oxide, the effect of suppressing the decrease in light reflectance according to the present invention is extremely small. On the other hand, when the synthetic resin film 5 has two or more layers, in the case where emphasis is placed on suppressing the decrease in mechanical strength due to ultraviolet rays, the inner synthetic resin film may contain rutile titanium oxide.

  The total thickness of the synthetic resin film 5 is preferably in the range of 80 to 300 μm. In the present invention, by increasing the total thickness of the synthetic resin film 5 to improve insulation, the thickness of the transparent polyester resin film 1 that is generally expensive can be reduced, thereby reducing the cost. Can be achieved. In particular, when the synthetic resin film 5 is provided in two layers, the thickness of each film is preferably in the range of 40 to 150 μm.

  In addition, since a rutile type titanium oxide is also a white pigment, if the synthetic resin film 5 contains a rutile type titanium oxide in the present invention, the synthetic resin film is colored white. When rutile-type titanium oxide is not blended in the synthetic resin film 5, the synthetic resin film 5 contains the above resin as a main component, and a light reflector, a light diffusing agent or a light absorber, a decorative agent, etc. One or two or more kinds of other coloring additives having an action may be added as appropriate.

  Examples of such other coloring additives include achromatic colorants such as whitening agents and blackening agents, or chromatic color systems such as red, orange, yellow, green, blue, purple, and the like. One or more colorants such as various dyes and pigments can be used.

  Of these, a whitening agent is added for the purpose of imparting light reflectivity, light diffusibility, etc. in order to efficiently recycle light by reflecting or diffusing the sunlight transmitted through the solar cell module. Furthermore, when the solar cell module is provided with designability, decorativeness, etc., and the solar cell module is installed on a roof or the like, there is also an effect of reflecting or diffusing the sunlight reflected back. . Examples of the whitening agent include one or two white pigments such as basic lead carbonate, basic lead sulfate, basic lead silicate, zinc white, zinc sulfide, lithopone, antimony trioxide, and anatase type titanium oxide. More than seeds can be used. As the usage-amount, in the resin composition which comprises the synthetic resin film 5, it exists in the range of 0.1-30 mass%, Preferably it exists in the range of 0.5-10 mass%. In the present invention, a gray achromatic dye / pigment in which a whitening agent and a blackening agent described later are mixed can also be used.

  For example, when the solar cell module is installed on a roof or the like, the blackening agent has an effect of imparting a design property or a decorative property suitable for the surrounding environment, for example, carbon black (channel Or furnace) and one or more black pigments such as black iron oxide can be used. In the present invention, the black layer formed by the blackening agent may be any black layer having a black taste such as a brown or brown black layer or a gray black layer. In the above, as the usage-amount of a blackening agent, in the resin composition which comprises the synthetic resin film 5, it exists in the range of 0.1-30 mass%, Preferably it exists in the range of 0.5-10 mass%.

  In addition, colorants such as chromatic dyes and pigments such as red, orange, yellow, green, blue, and purple are designed to suit the surrounding environment when the solar cell module is installed on a roof, for example. Such as organic dyes / pigments such as azo, anthraquinone, phthalocyanine, thioindigo, quinacridone, dioxazine, or the like, or Colorants such as inorganic pigments such as bitumen, chrome vermilion and bengara can be used. In the present invention, among the chromatic coloring additives as described above, it is particularly preferable to use a blue bluing agent. In the above, as the usage-amount, in the resin composition which comprises the synthetic resin film 5, it exists in the range of 0.1-30 mass%, Preferably it exists in the range of 0.5-10 mass%.

  Moreover, it is preferable to mix | blend 1 type, 2 or more types of a ultraviolet absorber, and 1 type or 2 types or more of light stabilizers with the synthetic resin film 5. FIG. Among these, as an ultraviolet absorber, the same thing in the transparent polyester-type resin film 1 can be used, As the addition amount, in the resin composition which comprises a synthetic resin film, 0.1-10 mass% Within the range, preferably within the range of 0.3 to 10% by mass. As a light stabilizer, an activated active species that is a photodegradation start source in a polymer is captured to prevent photodegradation. For example, one kind of hindered amine compound, hindered piperidine compound, etc. Or 2 or more types can be used. As the usage-amount, in the resin composition which comprises a synthetic resin film, it can be in the range of 0.1-10 mass%, Preferably it can be in the range of 0.3-10 mass%.

  Further, the synthetic resin film 5 may be provided with a plasticizer, an antioxidant, an antistatic agent, a crosslinking agent, a curing agent, a filler, a lubricant, a reinforcing agent, a reinforcing agent, a flame retardant, a flame retardant, and a foaming agent as desired. One or more additives such as an antifungal agent can be optionally added. In the present invention, it is particularly preferable to use a flame retardant among the above. Flame retardants are broadly classified into organic and inorganic types. Examples of organic types include phosphorus-based, phosphorus + halogen-based, chlorine-based, and bromine-based flame retardants, and inorganic types include, for example, hydroxylation. Flame retardants such as aluminum, antimony, magnesium hydroxide, guanidine, zirconium, zinc borate can be used, and flame retardancy is imparted by arbitrarily adding one or more of them. be able to. The synthetic resin film 5 needs to be able to ensure sufficient adhesion with the filler layer in constituting the solar cell module.

  The synthetic resin film 5 according to the present invention is formed of a resin composition prepared by blending various additives as desired with the above resin component, further adding a solvent, a diluent, etc., and kneading sufficiently. Is done.

  Specifically, in the present invention, using the above resin composition, for example, using an extruder, a T-die extruder, a cast molding machine, an inflation molding machine, etc., an extrusion method, a T-die extrusion method, a cast molding. A resin film or sheet can be produced by a film forming method such as a method or an inflation method, and further, for example, stretched in a uniaxial or biaxial direction using a tenter method or a tubular method, A desired synthetic resin film 5 can be obtained. In the present invention, for example, the resin composition prepared above is coextruded by a T-die coextrusion method, an inflation coextrusion method, or the like with or without a color additive added. Thus, it is also possible to produce a multilayer laminated resin film having an appropriate configuration.

  In addition, in this invention, the synthetic resin film 5 containing the additive for coloring etc. can also be manufactured as follows, for example. First of all, an ordinary vehicle for paint or ink is used as a main component, and one or more kinds of coloring additives and one or more kinds of other additives are added to this as desired. Further, a paint or ink composition is prepared by adding a solvent, a diluent and the like and kneading the mixture sufficiently. Next, this coating or ink composition is coated or printed on the surface of a heat-resistant synthetic resin film by using a normal coating method or printing method, so that a coating film containing a coloring additive on the surface is applied. Alternatively, a synthetic resin film having a printed film can be produced. In this case, the coloring additive or the like may not necessarily be added to the paint or ink composition if it has been kneaded into a heat-resistant synthetic resin film in advance. is there.

  Moreover, in this invention, the synthetic resin film 5 containing the additive for coloring etc. can also be manufactured as follows. First, one or two or more heat-resistant synthetic resins are mixed with a paint or ink vehicle as a main component, and one or more coloring additives are mixed with other ones as desired. One or two or more of these additives are added, and further, a solvent, a diluent and the like are added and kneaded sufficiently to prepare a paint or ink composition. Next, the coating or ink composition is directly applied or printed on the surface of the resin film provided with the above-described inorganic oxide vapor-deposited film, for example, using a normal coating method or printing method. A coating film or a printing film made of a heat-resistant synthetic resin containing a coloring additive or the like can be formed.

  In the present invention, when the synthetic resin film 5 is laminated by dry lamination, which will be described later, the surface is subjected to surface modification pretreatment such as corona discharge treatment, ozone treatment, or plasma discharge treatment in advance. It can be applied arbitrarily.

(Laminated)
In the present invention, when laminating the transparent polyester-based resin film 1, the base polyester-based resin film 4 and the synthetic resin film 5 having one or more layers, for example, via a laminate adhesive layer, Alternatively, a technique of melt extrusion lamination through an anchor coating agent layer, a melt extrusion resin layer, or the like can be used. Further, as described above, for the polypropylene resin film as the synthetic resin film 5, the surface of the resin film provided with a vapor deposition film of inorganic oxide by melt-extrusion of the polypropylene resin composition using an extruder or the like. Further, for example, melt extrusion lamination can also be performed directly or not via an adhesion aid layer or the like by an anchor coating agent or the like.

Among these, in the dry laminate lamination method, examples of the adhesive used for the adhesive layer for laminating include, for example, a polyvinyl acetate adhesive, a homopolymer such as ethyl acrylate, butyl, 2-ethylhexyl ester, and the like. Polyacrylic acid ester adhesives, such as copolymers with methyl methacrylate, acrylonitrile, styrene, etc., cyanoacrylate adhesives, copolymers of ethylene and monomers such as vinyl acetate, ethyl acrylate, acrylic acid, methacrylic acid, etc. Ethylene copolymer adhesive made of polymer, polyolefin adhesive made of polyethylene resin or polypropylene resin, cellulose adhesive, polyester adhesive, polyamide adhesive, polyimide adhesive, urea resin or Ami composed of melamine resin Resin adhesives, phenol resin adhesives, epoxy adhesives, polyurethane adhesives, polycarbonate adhesives, reactive (meth) acrylic adhesives, chloroprene rubber, nitrile rubber, styrene-butadiene rubber, styrene-isoprene Various adhesives such as a rubber-based adhesive made of rubber or the like, a silicone-based adhesive, an alkali metal silicate, an inorganic adhesive made of low-melting glass, or the like can be used. The composition system of these adhesives may be any composition form such as aqueous type, solution type, emulsion type, and dispersion type, and the form may be any form such as film / sheet form, powder form, solid form, etc. Further, the bonding mechanism may be any form such as a chemical reaction type, a solvent volatilization type, a heat melting type, and a hot pressure type. These adhesives can be applied, for example, by a coating method such as a roll coating method, a gravure roll coating method, a kiss coating method, or the like, or a printing method, and the coating amount is 0.1 to 10 g / m ^2. Within the range of (dry state) is desirable.

  In the present invention, among these adhesives, in particular, the use of a polyurethane-based adhesive, a polycarbonate-based adhesive, or a mixed adhesive thereof, these materials are excellent in hydrolysis resistance. In addition, it is preferable because it is a material suitable for the high cold resistance required in this application. Further, in the present invention, as the above-mentioned laminating adhesive, in order to cope with high heat resistance, moist heat resistance, etc., the resin as the main component of the vehicle constituting the adhesive is three-dimensionally crosslinked or cured. It is desirable to use a material that can form a network-like cross-linked structure. Specifically, it is preferable that the adhesive constituting the adhesive layer for laminating forms a crosslinked structure by reaction energy consisting of heat or light in the presence of a curing agent or a crosslinking agent. For example, in the present invention, the adhesive constituting the adhesive layer for laminating is, for example, in the presence of an isocyanate-based curing agent or a crosslinking agent such as aliphatic / alicyclic isocyanate or aromatic isocyanate, By forming a cross-linked structure with reaction energy consisting of heat or light, a back surface protection sheet for solar cell modules that is excellent in heat resistance, moist heat resistance and the like can be produced. In the above, as the aliphatic isocyanate, for example, 1,6-hexamethylene diisocyanate (HDI), as the alicyclic isocyanate, for example, isophorone diisocyanate (IPDI), and as the aromatic isocyanate, for example, tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), naphthylene diisocyanate (NDI), tolidine diisocyanate (TODI), xylylene diisocyanate (XDI) and the like can be used.

  In the present invention, the laminating adhesive is more preferably an adhesive comprising polyester polyurethane as a main component and an isocyanate and a silane coupling agent added, and the addition amount of the silane coupling agent is usually More specifically, an adhesive that is 3 to 8% by mass with respect to the main component is used.

  In the adhesive described above, the above-described ultraviolet absorber or light stabilizer can be added in order to prevent ultraviolet degradation or the like. As the ultraviolet absorber or light stabilizer, one or more of the aforementioned ultraviolet absorbers, or one or more of the light stabilizers can be used in the same manner. The amount used varies depending on the particle shape, density, etc., but is preferably in the range of 0.1 to 10% by mass.

In the melt extrusion lamination method, in order to obtain stronger adhesive strength, for example, an adhesion assistant such as an anchor coating agent may be used, and lamination may be performed via the anchor coating agent layer. it can. As such an anchor coat agent, for example, various aqueous or oil-based anchor coat agents such as organic titanium-based, isocyanate-based, polyethyleneimine-based, polyptadiene-based, such as alkyl titanate can be used. The anchor coating agent can be coated using a coating method such as roll coating, gravure roll coating, kiss coating, and the coating amount is in the range of 0.1 to 5 g / m ² (dry state). The inside is preferable.

  Furthermore, in the above melt extrusion lamination method, as the melt extrusion resin constituting the melt extrusion resin layer, for example, low density polyethylene, medium density polyethylene, high density polyethylene, linear (linear) low density polyethylene, polypropylene, Ethylene-vinyl acetate copolymer, ionomer resin, ethylene-ethyl acrylate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, ethylene-propylene copolymer, methylpentene polymer, polyethylene, polypropylene A resin such as an acid-modified polyolefin resin obtained by modifying a polyolefin resin such as acrylic acid, methacrylic acid, maleic anhydride, fumaric acid or the like with an unsaturated carboxylic acid can be used. The thickness of the melt-extruded resin layer is in the range of 5 to 100 μm, preferably in the range of 10 to 50 μm.

In the present invention, in order to improve the tight adhesion between the base polyester-based resin film 4 provided with the inorganic oxide vapor-deposited film 2 and the synthetic resin film 5, a primer coat agent layer or the like is arbitrarily added in advance. It can also be formed as a surface treatment layer. Examples of the primer coating agent include polyester resins, polyamide resins, polyurethane resins, epoxy resins, phenol resins, (meth) acrylic resins, polyvinyl acetate resins, and polyolefin resins such as polyethylene or polypropylene. Alternatively, a resin composition containing a copolymer or modified resin, a cellulose resin, or the like as a main component of the vehicle can be used. This primer coating agent layer can be formed, for example, by coating using a coating method such as roll coating, gravure roll coating, kiss coating, etc. The coating amount is 0.1 to 5 g / m ² (dry It is preferable to be within the range of (state).

  In the present invention, when two or more layers of the base polyester-based resin film 4 provided with the inorganic oxide vapor-deposited film 2 are laminated through a tough resin film as desired, and when two or more layers are synthesized In the case of laminating the resin film 5, as described above, dry lamination lamination method in which dry lamination lamination is performed via an adhesive layer for lamination, or melt extrusion through an anchor coating agent layer, a melt extrusion resin layer, or the like. Lamination can be performed in the same manner by using a method such as a melt extrusion lamination method for lamination. Here, when using the dry laminate lamination method or the melt extrusion lamination method, the above-mentioned laminating adhesive, anchor coating agent, melt extrusion resin, primer coating agent, and the like can be similarly used.

(Solar cell module)
FIG. 2 shows a schematic cross-sectional view of an example solar cell module of the present invention. As shown in the drawing, the solar cell module 100 of the present invention is formed by sequentially laminating a surface protective sheet 11, a filler layer 12, a solar cell element 13, a filler layer 14, and a back surface protective sheet 15. The back surface protection sheet for solar cell modules of the present invention is used as the back surface protection sheet 15 and is laminated so that the filler layer 14 and the surface opposite to the transparent polyester resin film 1, that is, the synthetic resin film 5 face each other. Being done. Thereby, generation | occurrence | production of the delamination at the time of manufacture of a solar cell module can be prevented, productivity can be improved, and it can also be excellent in cost efficiency.

  In the solar cell module of the present invention, the configuration other than the back surface protective sheet is not particularly limited, and can be appropriately configured according to a conventional method. Also, the layer structure of the solar cell module is not particularly limited, and it is laminated with any other layer optionally added to a known structure for the purpose of absorbing or reinforcing sunlight. Is something that can be done.

  As the surface protection sheet 11 for solar cell modules constituting the solar cell module 100 of the present invention, it has sunlight permeability, insulation properties, etc., weather resistance, heat resistance, light resistance, water resistance, wind pressure resistance, and resistance to wind. It has various characteristics such as rainfall resistance, chemical resistance, moisture resistance, and antifouling properties, is excellent in physical or chemical strength, toughness, etc., extremely durable, and solar From the viewpoint of protecting the battery element, it is necessary to have excellent scratch resistance, shock absorption and the like. Specific examples of such a surface protective sheet include not only known glass plates but also fluorine resins, polyamide resins (various nylons), polyester resins, polyethylene resins, polypropylene resins, and cyclic resins. Films or sheets of various resins such as polyolefin resins, polystyrene resins, (meth) acrylic resins, polycarbonate resins, acetal resins, and cellulose resins can be used. For example, a biaxially stretched resin film or sheet may be used as the resin film or sheet. The film thickness of the resin film or sheet is preferably in the range of 12 to 200 μm, more preferably in the range of 25 to 150 μm.

  Moreover, in the solar cell module 100 of this invention, as the filler layer 12 arrange | positioned between the surface protection sheet 11 and the solar cell element 13, since sunlight injects and permeate | transmits and absorbs this, it is transparent. In order to fulfill the function of maintaining the smoothness of the surface of the solar cell element as a photovoltaic element, it is also necessary to have adhesiveness with the surface protective sheet 11. It is necessary to have excellent scratch resistance, shock absorption, etc. from the viewpoint of thermoplasticity and protection of the solar cell element as the photovoltaic element. Specifically, for example, a polyolefin resin such as fluorine resin, ethylene-vinyl acetate copolymer, ionomer resin, ethylene-acrylic acid, or methacrylic acid copolymer, polyethylene resin, polypropylene resin, polyethylene or polypropylene, One kind of resin such as acid-modified polyolefin resin modified with unsaturated carboxylic acid such as acrylic acid, itaconic acid, maleic acid, fumaric acid, polyvinyl butyral resin, silicone resin, epoxy resin, (meth) acrylic resin, etc. Or a mixture of two or more of them can be used. In the present invention, the resin constituting the filler layer 12 includes, for example, a crosslinking agent, a heat, and the like within a range that does not impair the transparency in order to improve weather resistance such as heat resistance, light resistance, and water resistance. Additives such as antioxidants, light stabilizers, ultraviolet absorbers, and photo-antioxidants can be arbitrarily added and mixed. Among these, in the present invention, for the filler layer on the sunlight incident side, in consideration of weather resistance such as light resistance, heat resistance, and water resistance, a fluorine resin, a silicone resin, and an ethylene-vinyl acetate resin are used. It is preferable. The thickness of the filler layer 12 is preferably in the range of 200 to 1000 μm, more preferably in the range of 350 to 600 μm.

Furthermore, in the present invention, as the solar cell element 13 as a photovoltaic element constituting the solar cell module 100, a conventionally known one, for example, a single crystal silicon type solar cell element, a polycrystalline silicon type solar cell element or the like is used. Crystalline silicon solar electronic device, amorphous silicon solar cell device of single junction type or tandem structure type, III-V group compound semiconductor solar electronic device such as gallium arsenide (GaAs) or indium phosphorus (InP), cadmium tellurium (CdTe) II-VI compound semiconductor solar electronic devices such as copper indium selenide (CuInSe ₂ ), organic solar cell devices, and the like can be used. Furthermore, 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 also be used. In particular, in the present invention, as the solar cell element, for example, on a substrate such as a glass substrate, a plastic substrate, or a metal substrate, crystalline silicon such as a pn junction structure, amorphous silicon such as a pin junction structure, What forms an electromotive force part, such as a compound semiconductor, and comprises a solar cell element is suitable.

  Furthermore, in the solar cell module 100 of the present invention, as the filler layer 14 disposed between the solar cell element 13 and the back surface protective sheet 15, the back surface protective sheet 15 and the surface filler layer 12 are the same. It is also necessary to have the adhesive property of the solar cell element as a photovoltaic element, and to have the thermoplasticity to fulfill the function of maintaining the smoothness of the back surface of the solar cell element as the photovoltaic element, and the solar element as the photovoltaic element. From the viewpoint of protecting the battery element, it is necessary to have excellent scratch resistance, shock absorption, and the like. However, unlike the filler layer 12, the filler layer 14 does not necessarily have transparency. Specifically, as the filler layer 14, for example, a fluorine-based resin, an ethylene-vinyl acetate copolymer, an ionomer resin, ethylene-acrylic acid, or methacrylic acid copolymer is used in the same manner as the filler layer 12 described above. Polymers, polyethylene resins, polypropylene resins, polyolefin resins such as polyethylene or polypropylene, modified with unsaturated carboxylic acids such as acrylic acid, itaconic acid, maleic acid and fumaric acid, acid-modified polyorene fin-based resin, polyvinyl butyral resin A mixture of one or more resins such as a silicone resin, an epoxy resin, and a (meth) acrylic resin can be used. In the present invention, the resin constituting the filler layer 14 includes, for example, a crosslinking agent, a thermal antioxidant, a light stabilizer, and the like in order to improve weather resistance such as heat resistance, light resistance, and water resistance. Additives such as ultraviolet absorbers and photo-antioxidants can be optionally added and mixed. The thickness of the filler layer 14 is preferably in the range of 200 to 1000 μm, more preferably in the range of 350 to 600 μm.

  When manufacturing the solar cell module of the present invention, other materials such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, high-strength, Density polyethylene, linear low density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer resin, ethylene-ethyl acrylate copolymer, ethylene-acrylic acid or methacrylic acid copolymer, methyl Pentene polymer, polybutene resin, polyvinyl chloride resin, polyvinyl acetate resin, polyvinylidene chloride resin, vinyl chloride-vinylidene chloride copolymer, poly (meth) acrylic resin, polyacrylonitrile resin, polystyrene Resin, acrylonitrile-styrene copolymer (AS tree) ), Acrylonitrile-butadiene-styrene copolymer (ABS resin), polyester resin, polyamide resin, polycarbonate resin, polyvinyl alcohol resin, saponified ethylene-vinyl acetate copolymer, fluorine resin, diene The resin, polyacetal resin, polyurethane resin, nitrocellulose and other known resin films or sheets can be arbitrarily selected and used. In the present invention, the film or sheet may be any of unstretched and uniaxially or biaxially stretched. Moreover, although the thickness is arbitrary, it is preferable to select and use from the range of several micrometers-300 micrometers. Furthermore, in the present invention, the film or sheet may be any film such as extrusion film formation, inflation film formation, and coating film.

  Next, in this invention, as a method of manufacturing a solar cell module using the above materials, a well-known method can be used and it does not restrict | limit in particular. For example, first, the surface protection sheet for the solar cell module, the filler layer, the solar cell element as a photovoltaic element, and the filler layer are sequentially laminated, and further for the solar cell module of the present invention. The back protective sheet is laminated with the surface of the synthetic resin film facing the filler layer, and other materials are arbitrarily laminated between the layers as desired. Next, a solar cell module can be manufactured by thermocompression-molding each of the above-mentioned layers as an integral molded body using a normal molding method such as a lamination method in which these are integrated by vacuum suction or the like and thermocompression bonded. . In the above, if necessary, in order to enhance the adhesion between each layer, a heat-melt adhesive having a vehicle as a main component of a vehicle such as a (meth) acrylic resin, an olefin resin, a vinyl resin, A solvent-type adhesive, a photocurable adhesive, or the like can be used.

  Further, in the above lamination, each lamination facing surface has, as necessary, for example, corona discharge treatment, ozone treatment, low temperature plasma treatment using oxygen gas or nitrogen gas, Pretreatment such as glow discharge treatment, oxidation treatment using chemicals or the like can be optionally performed. Furthermore, in the above-mentioned lamination, a primer coating agent layer, an undercoat agent layer, an adhesive layer, an anchor coating agent layer, or the like is arbitrarily formed in advance on each lamination facing surface, and surface pretreatment is performed. You can also. Examples of the pretreatment coating agent layer include polyester resins, polyamide resins, polyurethane resins, epoxy resins, phenol resins, (meth) acrylic resins, polyvinyl acetate resins, polyethylene, and polypropylene. A resin composition containing a polyolefin resin or a copolymer or modified resin thereof, a cellulose resin, or the like as a main component of the vehicle can be used. In the above, as a method for forming the coating agent layer, for example, a solvent type, aqueous type, or emulsion type coating agent is used, and a coating method such as a roll coating method, a gravure roll coating method, or a kiss coating method is used. Can be used to coat.

  Furthermore, in the present invention, the above-mentioned filler layer is laminated on the synthetic resin film surface of the back surface protective sheet for solar cell module of the present invention, and a laminate in which the back surface protective sheet and the filler layer are laminated in advance. After that, a solar cell element as a photovoltaic element, a filler layer, and a surface protective sheet are sequentially laminated on the surface on the filler layer side that constitutes the laminate, and, if necessary, other materials The solar cell module is manufactured by laminating the above layers, using the usual molding method such as lamination method that integrates them by vacuum suction etc. You can also

Hereinafter, the present invention will be described in more detail with reference to examples.
<Example 1>
A polyethylene terephthalate film having a thickness of 12 μm (Unitika Ltd., PET # 12) was used as the base film, and this was mounted on the unwinding roll of the plasma chemical vapor deposition apparatus, and then the line speed was 150 mm / Conveyed in min, using a glow discharge plasma generator, argon gas 0.1 Pa · m ³ / sec was introduced, plasma treatment was performed at an output of 5 kW, and the substrate film was plasma treated with an inert gas A surface was formed. Then, a 200 nm thick silicon oxide vapor deposition film was formed on the plasma treated surface under the following conditions.

(Deposition conditions)
Reaction gas mixing ratio: hexamethyldisiloxane: oxygen gas: helium = 0.2: 0.85: 0.42 (unit: Pa · m ³ / sec)
Ultimate pressure: 5.0 × 10 ⁻⁵ mbar
Film ^- forming pressure: 3.0 × 10 ⁻² mbar
Line speed: 50 m / min
Power: 15kW

Next, immediately after forming the silicon oxide vapor deposition film having a thickness of 200 mm as described above, a glow discharge plasma generator is used on the silicon oxide vapor deposition film surface, and the power is 9 kW, oxygen gas (O ₂ ): argon gas. (Ar) = 1.18: 0.42 (unit: Pa · m ³ / sec), using a mixed gas, mixed gas pressure 6 × 10 ⁻² mbar, oxygen / argon mixed gas at a processing speed of 150 m / min Plasma treatment was performed to form a plasma-treated surface in which the surface tension of the deposited silicon oxide film surface was improved by 54 dyne / cm or more.

  On the other hand, according to the composition shown in Table 1 below, an ethylene-vinyl alcohol copolymer resin (EVOH, manufactured by Nippon Synthetic Chemical Co., Ltd., trade name: Soarnol D2908, ethylene copolymerization ratio 29%) is mixed with isopropyl alcohol and ion-exchanged water. To the EVOH solution (composition a.) Dissolved in the mixed solvent, a hydrolyzed solution (composition b.) Composed of ethyl silicate 40 (manufactured by Colcoat Co., Ltd.), isopropyl alcohol, acetylacetone aluminum and ion-exchanged water prepared in advance was added. Furthermore, a liquid mixture (composition c) comprising a polyvinyl alcohol aqueous solution prepared in advance, a silane coupling agent (manufactured by Dow Corning Toray Co., Ltd., trade name: epoxy silica SH6040), acetic acid, isopropyl alcohol and ion-exchanged water. .) Is added and stirred. To obtain a barrier coating solution of clear (gas barrier composition).

Subsequently, the gas barrier composition produced above was used for the plasma treatment surface of the silicon oxide vapor deposition film formed above, and this was coated by a gravure roll coating method. Thereafter, heat treatment was performed at 100 ° C. for 30 seconds to form a gas barrier coating film having a thickness of 0.4 g / m ² (dry state).

The base film on which the gas barrier coating film is formed is mounted on the unwinding roll of the plasma chemical vapor deposition apparatus, and then conveyed at a line speed of 150 mm / min, and argon gas is 0.1 Pa · m ³ / sec. Then, plasma treatment was performed at an output of 5 kW to form a plasma treatment surface with an inert gas on the surface of the gas barrier coating film. Then, a 200 nm thick silicon oxide vapor deposition film was formed on the plasma treated surface under the following conditions.

(Deposition conditions)
Reaction gas mixing ratio: Hexalmethyldisiloxane: Oxygen gas: Helium = 0.2: 0.85: 0.42 (unit: Pa · m ³ / sec)
Ultimate pressure: 5.0 × 10 ⁻⁵ mbar
Film ^- forming pressure: 3.0 × 10 ⁻² mbar
Line speed: 150 m / min
Power: 15kW

Next, immediately after forming the silicon oxide vapor deposition film having a thickness of 200 mm as described above, a glow discharge plasma generator is used on the silicon oxide vapor deposition film surface, and the power is 9 kW, oxygen gas (O ₂ ): argon gas. Using a mixed gas of (Ar) = 1.18: 0.42 (unit: Pa · m ³ / sec), oxygen / argon at a mixed gas pressure of 6 × 10 ⁻² mbar and a processing speed of 150 m / min. A mixed gas plasma treatment was performed to form a plasma treated surface in which the surface tension of the deposited silicon oxide film surface was improved by 54 dyne / cm or more.

Furthermore, on the plasma-treated surface formed above, 8.0% by mass of an epoxy-based silane coupling agent (trade name: SH6040, manufactured by Toray Dow Corning Co., Ltd.) with respect to the initial condensate of the polyester-based resin, and Using a primer resin composition obtained by adding 1.0% by mass of an anti-blocking agent (Fuji Silysia Chemical Co., Ltd., trade name: Silo Hovic) and kneading it sufficiently, A primer film was formed by coating so as to have a film thickness of 0.2 g / m ² (in a dry state) to produce a laminated film having a gas barrier coating film.

Next, a polyurethane adhesive (A1143 / A50, manufactured by Mitsui Chemicals Polyurethane Co., Ltd.) was applied to the plasma-treated surface of the silicon oxide vapor-deposited surface of the base film produced above by a gravure roll coating method. An adhesive layer for laminating was formed by coating so as to be 0.0 to 6.0 g / m ² (dry state).

  Next, a biaxially stretched polyethylene terephthalate film having a thickness of 50 μm and having resistance to hydrolysis (X10S # 50, manufactured by Toray Industries, Inc.) is laminated on the surface of the adhesive layer for lamination formed as described above. After that, both were laminated by dry lamination.

  On the other hand, 25% by mass of rutile titanium oxide (average particle size 0.5 μm), 1% by mass of a benzophenone-based ultraviolet absorber as an ultraviolet absorber, and a hindered amine-based light stabilizer as a light stabilizer. 1% by mass was added, and other necessary additives were added, and kneaded thoroughly to prepare a polypropylene resin composition. Subsequently, this polypropylene resin composition was melt-extruded using a T-die extruder to produce a white colored unstretched polypropylene resin film having a thickness of 80 μm. Furthermore, corona discharge treatment was performed on both surfaces of the obtained white colored unstretched polypropylene resin film according to a conventional method to form corona-treated surfaces.

Next, an adhesive similar to the above is used on one corona-treated surface of the white colored unstretched polypropylene resin film produced above, and this is coated with a film thickness of 4.0 to 6.0 g / g by a gravure roll coating method. Coating was performed so as to be m ² (dry state) to form an adhesive layer for laminating. Next, the surface of the adhesive layer for laminating is overlapped with the non-deposited surface of silicon oxide of the base film facing each other, and then both of them are dry-laminated and laminated for the solar cell module of Example 1. A back protective sheet was produced.

  Next, a biaxially stretched polyethylene terephthalate film with a thickness of 38 μm, in which solar cell elements made of amorphous silicon are arranged in parallel, a glass plate with a thickness of 3 mm, an ethylene-vinyl acetate copolymer sheet with a thickness of 400 to 600 μm, and a thickness of The 400 μm ethylene-vinyl acetate copolymer sheet and the back protective sheet for solar cell module produced above were faced with the white-colored unstretched polypropylene resin film surface, and the solar cell element surface was facing up. Then, the solar cell module of Example 1 was manufactured by laminating through an adhesive layer of acrylic resin and integrating by vacuum press lamination at 150 ° C. for 30 minutes.

<Example 2>
A polyethylene terephthalate film (Mitsubishi Resin Co., Ltd., Techbarrier L # 12) having a thickness of 12 μm with silica (silicon oxide) deposited on the surface is used as a base film, and then a polyurethane adhesive (Mitsui Chemical Polyurethane Co., Ltd., A1143 / A50) is deposited on the silicon oxide vapor-deposited surface of the silica vapor-deposited film by a gravure roll coat method so that the film thickness becomes 4.0 to 6.0 g / m ² (dry state). To form an adhesive layer for laminating.

  Next, a biaxially stretched polyethylene terephthalate film having a thickness of 50 μm and having resistance to hydrolysis (X10S # 50, manufactured by Toray Industries, Inc.) is laminated on the surface of the adhesive layer for lamination formed as described above. After that, both were laminated by dry lamination.

  On the other hand, 25% by mass of rutile titanium oxide (average particle size 0.5 μm), 1% by mass of a benzophenone-based ultraviolet absorber as an ultraviolet absorber, and a hindered amine-based light stabilizer as a light stabilizer. 1% by mass was added, and other necessary additives were added, and kneaded thoroughly to prepare a polypropylene resin composition. Subsequently, this polypropylene resin composition was melt-extruded using a T-die extruder to produce a white colored unstretched polypropylene resin film having a thickness of 80 μm. Furthermore, corona discharge treatment was performed on both surfaces of the obtained white colored unstretched polypropylene resin film according to a conventional method to form corona-treated surfaces.

Next, an adhesive similar to the above is used on one corona-treated surface of the white colored unstretched polypropylene resin film produced above, and this is coated with a film thickness of 4.0 to 6.0 g / g by a gravure roll coating method. Coating was performed so as to be m ² (dry state) to form an adhesive layer for laminating. Next, the non-deposited surface of the silicon oxide of the substrate film is opposed to the surface of the adhesive layer for laminating, and then both are dry laminated to form the solar cell module of Example 2. A back protective sheet was produced.

  Next, a biaxially stretched polyethylene terephthalate film with a thickness of 38 μm, in which solar cell elements made of amorphous silicon are arranged in parallel, a glass plate with a thickness of 3 mm, an ethylene-vinyl acetate copolymer sheet with a thickness of 400 to 600 μm, and a thickness of The 400 μm ethylene-vinyl acetate copolymer sheet and the back protective sheet for solar cell module produced above were faced with the white-colored unstretched polypropylene resin film surface, and the solar cell element surface was facing up. Then, the solar cell module of Example 2 was manufactured by laminating through an adhesive layer of an acrylic resin and integrating by vacuum press lamination at 150 ° C. for 30 minutes.

<Example 3>
A polyethylene terephthalate film (Mitsubishi Resin Co., Ltd., Techbarrier L # 12) having a thickness of 12 μm with silica (silicon oxide) deposited on the surface is used as a base film, and then a polyurethane adhesive (Mitsui Chemical Polyurethane Co., Ltd., A1143 / A50) is deposited on the silicon oxide vapor-deposited surface of the silica vapor-deposited film by a gravure roll coat method so that the film thickness becomes 4.0 to 6.0 g / m ² (dry state). To form an adhesive layer for laminating.

  Next, 20% by mass of a rutile titanium oxide having a thickness of 50 μm and having an average particle diameter of 0.5 μm added as a white pigment is added to the surface of the adhesive layer for laminating formed above. Colored biaxially stretched polyethylene terephthalate films were placed facing each other and then laminated together in a dry laminate.

  On the other hand, 25% by mass of rutile titanium oxide (average particle size 0.5 μm), 1% by mass of a benzophenone-based ultraviolet absorber as an ultraviolet absorber, and a hindered amine-based light stabilizer as a light stabilizer. 1% by mass was added, and other necessary additives were added, and kneaded thoroughly to prepare a polypropylene resin composition. Subsequently, this polypropylene resin composition was melt-extruded using a T-die extruder to produce a white colored unstretched polypropylene resin film having a thickness of 80 μm. Furthermore, corona discharge treatment was performed on both surfaces of the obtained white colored unstretched polypropylene resin film according to a conventional method to form corona-treated surfaces.

Next, an adhesive similar to the above is used on one corona-treated surface of the white colored unstretched polypropylene resin film produced above, and this is coated with a film thickness of 4.0 to 6.0 g / g by a gravure roll coating method. Coating was performed so as to be m ² (dry state) to form an adhesive layer for laminating. Next, the non-deposited surface of the silicon oxide of the base film is opposed to the surface of the adhesive layer for laminating, and then both are laminated by dry lamination, for the solar cell module of Example 3. A back protective sheet was produced.

  Next, a biaxially stretched polyethylene terephthalate film with a thickness of 38 μm, in which solar cell elements made of amorphous silicon are arranged in parallel, a glass plate with a thickness of 3 mm, an ethylene-vinyl acetate copolymer sheet with a thickness of 400 to 600 μm, and a thickness of The 400 μm ethylene-vinyl acetate copolymer sheet and the back protective sheet for a solar cell module produced above are opposed to the surface of the white colored unstretched polypropylene resin film, and the solar cell element surface is turned up. Then, the solar cell module of Example 3 was manufactured by laminating through an adhesive layer of acrylic resin and integrating by vacuum press lamination at 150 ° C. for 30 minutes.

<Comparative Example 1>
In the same manner as in Example 1, except that 5% by mass of anatase-type titanium oxide (average particle size 0.5 μm) was added to the white colored unstretched polypropylene resin film in Example 1 instead of 5% by mass of rutile-type titanium oxide. And the back surface protection sheet for solar cell modules and the solar cell module of the comparative example 1 were manufactured.

<Comparative Example 2>
In place of hydrolysis-resistant PET (made by Toray Industries, Inc., X10S) in Example 1, using general industrial PET (produced by Toray Industries, Inc., S-10 # 50), in a white colored unstretched polypropylene resin film In the same manner as in Example 1 except that 5% by mass of anatase-type titanium oxide (average particle size 0.5 μm) was added instead of 5% by mass of rutile-type titanium oxide, the back surface protection for solar cell modules of Comparative Example 2 Sheets and solar cell modules were manufactured.

<Comparative Example 3>
In place of hydrolysis-resistant PET (made by Toray Industries, Inc., X10S) in Example 1, general industrial white PET (manufactured by Teijin DuPont Co., Ltd., U2 # 50) was used, and in a white colored unstretched polypropylene resin film In the same manner as in Example 1 except that 5% by mass of anatase-type titanium oxide (average particle size 0.5 μm) was added instead of 5% by mass of rutile-type titanium oxide, the back surface protection for solar cell modules of Comparative Example 3 Sheets and solar cell modules were manufactured.

  About the back surface protection sheet for solar cell modules manufactured above, durability (mechanical strength, barrier performance) and power generation performance (reflectance) were evaluated according to the following.

(1) Hydrolysis resistance test Each obtained back surface protection sheet was subjected to a pressure cooker test apparatus (manufactured by Hirayama Seisakusho) for 72 hours in an environment of 120 ° C and 85% RH, and 85 ° C in a constant temperature and humidity oven. Each was stored for 1500 hours in an environment of 85% RH.

(2) Ultraviolet resistance test Using a xenon irradiation device (Toyo Seiki, Atlas Weatherometer Ci4000), the PET surface and PP surface of each back protection sheet were irradiated with ultraviolet rays for 1000 hours under irradiation conditions in accordance with ASTM G155. .

<Measurement of mechanical strength>
Each back surface protection sheet was cut out at 15 mm × 50 mm, and the breaking strength was measured using a tensile tester (manufactured by A & D Co., Ltd., model name Tensilon). The measurement was performed on the sample after the pressure cooker test, after the constant temperature and humidity storage, and after the ultraviolet irradiation of the PET surface, and the maintenance ratio of the breaking strength from the initial value was obtained. The results are shown in Tables 1 and 2 below.

<Measurement of reflectance>
About the PP resin side of each back surface protection sheet, the reflectance (%) with respect to the light ray with a wavelength of 400 nm was measured with the spectrophotometer. The measurement was performed on samples before and after UV irradiation on the PP surface. The results are shown in Table 3 below.

<Barrier performance evaluation (measurement of water vapor permeability)>
The water vapor permeability is measured using a measuring instrument (model name, PERMATRAN W-3 / 31) manufactured by MOCON, USA, under the conditions of a temperature of 40 ° C. and a humidity of 100% RH for each back protection sheet. Measurements were made on samples after initial value, pressure cooker test, and storage at constant temperature and humidity, and the results are shown in Table 4 below.

  As shown in the above table, in the back surface protection sheet of each example according to the present invention, compared with the back surface protection sheet of the comparative example, even after storage in a high temperature and high humidity environment or an ultraviolet irradiation environment, It was confirmed that the mechanical strength, the barrier performance and the reflectance were well maintained.

DESCRIPTION OF SYMBOLS 1 Transparent polyester-type resin film 2 Deposition film | membrane 3 of inorganic oxide 3 Gas barrier coating film 4 Base polyester-type resin film 5 Synthetic resin films 6, 7 Adhesive layer 10 Back surface protection sheet 11 Surface protection sheet 12, 14 Filler layer 13 Solar cell element 15 Back surface protection sheet 21 Retractable vacuum deposition apparatus 22, 42 Vacuum chamber 23, 43 Unwind roll 24, 25 Guide roll 26 Coating drum 27 Crucible 28 Deposition source 29 Oxygen gas outlet 30 Mask 31, 32 Guide roll 33, 54 Winding roll 41 Plasma chemical vapor deposition apparatus 44, 53 Auxiliary roll 45 Cooling / electrode drum 46, 47 Gas supply apparatus 48 Raw material volatilization supply apparatus 49 Raw material supply nozzle 50 Glow discharge plasma 51 Power supply 52 Magnet 55 Vacuum pump 100 Solar cell module 101 base film

Claims (8)

A transparent polyester resin film, a base polyester resin film having at least one layer of an inorganic oxide vapor deposition film and a gas barrier coating film on at least one surface, and at least one layer of a synthetic resin film are adhesives It is a back surface protection sheet for solar cell modules that is sequentially laminated through layers,
Either one or both of the said transparent polyester-type resin film and a synthetic resin film contain a rutile type titanium oxide, The back surface protection sheet for solar cell modules characterized by the above-mentioned.   The back surface protective sheet for a solar cell module according to claim 1, wherein the content of the rutile-type titanium oxide is in the range of 1 to 30% by mass of the resin composition constituting the film.   The back surface protective sheet for a solar cell module according to claim 1 or 2, wherein the rutile-type titanium oxide has an average particle size of 0.1 to 3.0 µm.   The back surface protection sheet for solar cell modules as described in any one of Claims 1-3 in which the said synthetic resin film has an olefin resin as a main component.   The back surface protection sheet for solar cell modules of Claim 4 in which the said synthetic resin film has a polypropylene resin as a main component.   The back surface protection sheet for solar cell modules as described in any one of Claims 1-5 by which the light stabilizer is mix | blended with the said synthetic resin film.   The back protective sheet for a solar cell module according to claim 6, wherein the light stabilizer comprises one or more of hindered amine compounds. A solar cell module in which a surface protective sheet, a filler layer, a solar cell element, a filler layer, and a back surface protective sheet are sequentially laminated,
The said back surface protection sheet is a back surface protection sheet for solar cell modules as described in any one of Claims 1-7, And it is laminated | stacked so that the said filler layer and the said synthetic resin film may oppose. A featured solar cell module.

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