JPH091716A - Photochromic laminate and manufacture thereof - Google Patents

Abstract

PURPOSE: To provide a photochromic laminate, which has the excellent transparency, the sufficient impact resistance and the penetration resistance, and a simple manufacturing method thereof. CONSTITUTION: A layer of a cross-linking polymer, whose main component is a (meta)alkyl acrylate containing a photochromic material, is provided between at least two transparent plates.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminate having photochromic properties and a method for producing the same. Conventionally, a laminated body using a transparent plate such as glass or transparent synthetic resin is used for the purpose of improving the brittleness of glass or transparent synthetic resin alone or preventing scattering of fragments generated at the time of breaking. , Transparent plates are adhered to each other using an organic polymer sheet or film. These are used in various openings such as windows and doors of houses, as well as in windshields and sunroofs of automobiles where light transmission is required. In these applications, recently, from the viewpoint of creating a comfortable living space, dimming performance that controls the amount of light passing through within a certain range has been required even if it is transparent. As a laminate having such dimming performance, Japanese Patent Laid-Open No. 1-1
Japanese Patent No. 38541 discloses a light control laminated glass in which a light control resin layer containing a polyvinyl butyral resin, an epoxy resin and a photochromic substance as main components is provided between a pair of transparent glasses. Further, JP-A-3-115143 discloses a photochromic laminated glass in which a transparent sheet containing a photochromic composition and a sheet in which a pigment is dispersed are sandwiched between two pieces of glass. [0003] Generally, polyvinyl butyral or a similar interlayer film sheet is used between transparent supports for producing a laminate. Common laminated glass has a thickness of 0.4 mm as an interlayer film sheet.
Polyvinyl butyral is used to some extent, but impact resistance when used for various openings such as windows,
Penetration resistance is not sufficient. Therefore, in automotive applications, the thickness of the interlayer film is further increased to improve impact resistance and penetration resistance. Increasing the thickness of this interlayer film improves impact resistance and penetration resistance, but at the same time reduces transparency. When polyvinyl butyral or a similar interlayer film sheet is used, a laminate is generally produced by thermocompression bonding. Examples of the method for thermocompression bonding include a method of pressure-removing air between a transparent support and an interlayer film under reduced pressure in an autoclave to perform pressure bonding, a method of pressure bonding with a roll, a method of pressure bonding with a press, and the like.
In any of these methods, the manufacturing process is complicated and the equipment required for manufacturing becomes large. further,
Operations such as dipping, kneading, printing, and spraying are necessary to preliminarily contain the photochromic substance in the interlayer film sheet. For example, according to the disclosure of JP-A-1-138541, polyvinyl butyral, an epoxy resin, and a photochromic substance are once dissolved and mixed in a solvent to form an intermediate film containing the photochromic substance, and then the solvent is evaporated. As with drying, many operations are required to produce interlayer films containing photochromic materials. Also, when kneading the photochromic substance, it is necessary to raise the temperature to a high temperature at which the resin forming the interlayer film sheet has sufficient fluidity, and depending on the photochromic substance contained, deterioration due to heat may occur. Is a problem. Further, when the interlayer film sheet is immersed in the solution containing the photochromic substance, it is difficult to impregnate the photochromic substance at a constant concentration due to variations in the immersion time and the drying conditions. If it is not completely removed, the adhesiveness of the interlayer film sheet of the laminate will be deteriorated after long-term use. Therefore, the present invention has good transparency,
Provided are a photochromic laminate having sufficient impact resistance and penetration resistance, and a simple method for producing the same. The present invention provides at least two
A photochromic laminate in which a layer of a cross-linked polymer containing a photochromic substance-containing (meth) acrylic acid alkyl ester unit as a main component is interposed between a plurality of transparent plates. Then, a gasket is interposed around at least two transparent plates facing each other, the outer periphery is clamped to form a cell, and the (meth) acrylic acid alkyl ester monomer and one molecule are formed inside the cell. A method for producing a photochromic laminate comprising encapsulating a mixed solution of a monomer having at least two unsaturated double bonds and a photochromic substance therein, followed by polymerization and curing, and further comprising at least two flat plates facing each other. Transparent plates are installed on both inner surfaces, a gasket is interposed around the transparent plates, and the outer circumference is clamped to form a cell. Inside the cell, a (meth) acrylic acid alkyl ester monomer is added. The mixture of a monomer having at least two unsaturated double bonds in one molecule and a photochromic substance is encapsulated and then polymerized and cured [claim 1]. It is a manufacturing method of Tokuromikku laminate. The transparent plate in the present invention may be a glass plate or a transparent plate material made of a synthetic resin such as a methacrylate resin or a polycarbonate resin. Among them, when used as a glazing material, a glass plate or a methacrylate resin plate is preferable because scratch resistance is required for a long period of time. As the glass plate here, not only a general glass plate but also a chemically and thermally strengthened glass plate can be used. It may be decided depending on how it is used. The methacrylate resin plate is a resin plate composed of methyl methacrylate alone or a copolymer of 50% by weight or more of methyl methacrylate and another copolymerizable ethylenically unsaturated monomer. Examples of the ethylenically unsaturated monomer copolymerizable with the methyl methacrylate include ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, benzyl methacrylate, 2-ethylhexyl methacrylate, 2-hydroxyethyl methacrylate and glycidyl. Methacrylic acid esters such as methacrylate, methyl acrylate, ethyl acrylate, butyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, 2-ethylhexyl acrylate, 2
-Acrylic acid esters such as hydroxyethyl acrylate and glycidyl acrylate, unsaturated acids such as methacrylic acid and acrylic acid, styrene, α-methylstyrene, acrylonitrile, methacrylonitonil, maleic anhydride, phenylmaleimide, cyclohexylmaleimide, etc. . Further, the copolymer forming the methacrylate resin plate may contain a glutaric anhydride unit and a glutarimide unit. Further, as these methacrylate resin plates, those having a film formed on the surface thereof by a commonly known method can be used in order to increase the surface hardness and improve the scratch resistance. The transparent plate constituting the laminate of the present invention is usually 2
Although it is a sheet, it may be three or more sheets if necessary, and the thickness thereof is preferably appropriately selected according to the application. The photochromic substance in the present invention is not particularly limited as long as it is a compound showing known photochromic properties. Examples thereof include organic photochromic substances such as spiropyran compounds, spirooxazine compounds, fulgide compounds, aromatic olefin compounds, and inorganic photochromic substances such as silver halides. Of these, silver halide and spirooxazine compounds are preferred because of their excellent repeatability and durability. Further, since the organic photochromic substance is easily dissolved in the monomer constituting the cross-linked polymer described later,
It can be uniformly dispersed in the crosslinked polymer. The amount of the photochromic substance contained in the crosslinked polymer depends on the kind of the photochromic substance used and the thickness of the crosslinked polymer, but is generally 0.01 to 3% by weight in the crosslinked polymer. It is an amount. When this amount is small, the laminated plate does not show effective photochromic characteristics against ultraviolet rays and visible rays from the outside. If it is too much, it will be colored with a slight amount of light and the transparency will be impaired. The crosslinked polymer in the present invention means (meth)
A monomer mainly composed of acrylic acid alkyl ester,
It is a polymer obtained by copolymerizing a polyfunctional monomer having two or more unsaturated double bonds in one molecule. And
The degree of cross-linking of the cross-linked polymer is preferably such that the gel fraction thereof is 80% or more in order that the cross-linked polymer layer stably adheres the transparent plates to each other for a long period of time and maintains the shape. Examples of the alkyl ester of (meth) acrylic acid used herein include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, cyclohexyl (meth) acrylate, phenyl (meth) acrylate and benzyl. (Meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-
Examples thereof include hydroxyethyl (meth) acrylate, glycidyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, and stearyl (meth) acrylate. In addition, this amount is 50% by weight or more of the crosslinked polymer constituting the composition. As the polyfunctional monomer having two or more radically polymerizable double bonds in one molecule, for example, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di ( (Meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, polyurethane di (meth) acrylate, divinylbenzene, allyl methacrylate, trimethylolpropane tri (meth) acrylate , Neopentyl glycol di (meth) acrylate, diallyl phthalate and the like. The type and amount of the polyfunctional monomer to be used vary depending on the physical properties required for the desired laminate and may be appropriately selected, but the gel fraction of the crosslinked polymer is 8 as described above.
The amount is preferably 0% or more. Further, unsaturated monomers other than the above which can be copolymerized with these monomers constituting the crosslinked polymer can be used. Examples of the unsaturated monomer here include unsaturated acids such as methacrylic acid and acrylic acid, styrene,
Examples include α-methylstyrene, acrylonitrile, methacrylonitonyl, maleic anhydride, phenylmaleimide, cyclohexylmaleimide and the like. Of these, unsaturated acids such as methacrylic acid and acrylic acid are preferable. The cross-linked polymer contains a known coloring agent,
You may mix various additives, such as a stabilizer, an ultraviolet absorber, an antioxidant, and a flame retardant. In particular, when a glass plate is used as the transparent plate, a known silane coupling agent or the like may be added to enhance the adhesive force with the glass. The crosslinked polymer is interposed as an intermediate layer between at least two transparent plates. The thickness may be determined according to the impact resistance required depending on the purpose of use, but is generally about 0.7 mm to 10 mm. In the laminated body of the present invention, when the number of the transparent plates is two, the intermediate layer has one layer, and finally has a three-layer structure. 3 transparent plates
In the case of one sheet, it has a five-layer structure. The method for producing the laminate of the present invention is a method to which a known so-called cell cast method for producing an acrylic resin plate is applied. That is, the transparent plate is used for the flat plates facing each other forming the cell, the gasket is arranged around the transparent plate, and the periphery is clamped with a shrimp vise, a W clip, a U-shaped clamp, etc. Then, there is a method in which a mixed liquid of a monomer as a raw material of the crosslinked polymer layer and a photochromic substance is sealed in the cell and polymerized. The thickness of the crosslinked polymer as an intermediate layer is roughly determined by the thickness of the gasket. The mixed liquid of the monomer as the raw material of the crosslinked polymer and the photochromic substance is composed of the monomers constituting the above-mentioned crosslinked polymer and the kind and amount of the photochromic substance contained in the crosslinked polymer. And other various additives and polymerization initiators. Examples of the polymerization initiator include known organic peroxides such as benzoyl peroxide, di-t-butyl peroxide, t-butyl peroxy 2-ethylhexanoate or azo compounds such as azobisisobutyronitrile and azobisdimethylvaleronitrile. And radical photoinitiators such as benzoin, benzoin ether, and 1-hydrohexyl phenyl ketone. The amount of these initiators is 0.001 with respect to 100 parts by weight of the monomer.
About 1 part by weight. Further, it may be in the form of a syrup containing a polymer soluble in these monomers. After enclosing the mixed solution inside the cell,
Polymerize and cure. Polymerization and curing are also thermal radical polymerization methods used in well-known cell casting methods, for example, a method of polymerizing cells in a water bath or an air bath at 50 to 130 ° C. for 1 to several tens of hours, or a photopolymerization method by ultraviolet irradiation. To be As another method, the transparent plate is installed on the inner surfaces of the flat plates facing each other forming the cell, a gasket is arranged inside the transparent plate, and the periphery thereof is clamped to form a cell, and so on. There is a way to do it. INDUSTRIAL APPLICABILITY The present invention provides a photochromic laminate excellent in impact resistance and penetration resistance by the well-known cell casting method. This laminated body can be suitably used especially in places where the amount of incident light is large among glazing materials such as public facilities, exercise facilities, general houses and buildings, or vehicles. The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. The obtained photochromic laminate was evaluated according to the following method. -Impact resistance: Based on a falling ball test of a laminated glass in accordance with JIS R 3205, evaluation was made on the state of destruction when a 1040 g hard ball was dropped from a height of 120 cm.・ Photochromic characteristics: A test piece of 50 mm x 50 mm was prepared, and the light transmittance (%) in the dark and 366 n with an ultraviolet lamp
The light transmittance (%) after irradiating m light for 1 minute is JISK710
According to 5, the measurement was performed using a haze meter, and the difference (ΔT) was taken as the photochromic property. Gel fraction: About 1 g of the crosslinked polymer was stirred in 100 g of toluene at room temperature for 24 hours. The insoluble residue was filtered and then dried at 130 ° C. for 3 hours, and the weight after drying (this weight is referred to as W) was measured and expressed as a percentage. Example 1 In a 200 ml round bottom flask, methyl methacrylate 28.5
Parts by weight, 66.5 parts by weight of 2-ethylhexyl acrylate,
Methacrylic acid 5.0 parts by weight, polyethylene glycol dimethacrylate (NK ester 23G, Shin Nakamura Chemical Co., Ltd.)
12.9 parts by weight, azobisisobutyronitrile 0.1 parts by weight,
Spironaphthoxazine (Photorome I
0.03 part by weight (manufactured by Nippon Chemix) was added, and the mixture was stirred and mixed at room temperature for 15 minutes to obtain a monomer mixture liquid. The monomer mixture was left under reduced pressure for 10 minutes for defoaming. A 2 mm gasket was sandwiched between two glass plates (size 800 × 800 mm, thickness 2 mm) and the periphery was fixed with clips to form a cell. A cell was prepared, and the above-mentioned monomer mixture solution was injected into the cell. Place this cell in a hot air drying oven at 75 ° C for 6 hours at 120 ° C.
The mixture was kept for 1 hour to polymerize the monomer mixture, and then cooled to room temperature to obtain a transparent laminate. The obtained laminated body was evaluated. Table 1 shows the evaluation results. Example 2 12.9 parts by weight of polyethylene glycol dimethacrylate (NK ester 23G, manufactured by Shin Nakamura Chemical Co., Ltd.) of Example 1,
Instead of urethane modified polypropylene glycol diacrylate (NK Oligo U-340AX Shin Nakamura Chemical Co., Ltd.) 1
Use 0.0 parts by weight of 0.05% spironaphthoxazine
The same procedure as in Example 1 was carried out except that the weight part was used. Table 1 shows the evaluation results. Example 3 In a 200 ml round bottom flask, methyl methacrylate 9.5
Parts by weight, 2-ethylhexyl methacrylate 80.5 parts by weight, methacrylic acid 5.0 parts by weight, ethylene glycol dimethacrylate 1.0 parts by weight, azobisisobutyronitrile 0.1 parts by weight, spironaphthoxazine (photorome
1.0 part by weight of Photorome-I Nippon Chemix) was added, and the mixture was stirred and mixed at room temperature for 15 minutes to obtain a monomer mixture liquid. The monomer mixture was left under reduced pressure for 10 minutes for defoaming. A methacrylic resin plate (made by Sumipex Sumitomo Chemical Co., Ltd., size 800) on a glass plate (size 800 x 800 mm, thickness 10 mm)
X 800 mm, thickness 2 mm) was installed. A 1.5 mm gasket was placed on the methacrylic resin plate, and another methacrylic resin plate was placed. Further, a glass plate (size: 800 × 800 mm, thickness: 10 mm) was placed on this, and the periphery was fixed with a clip to form a cell. After enclosing the above-mentioned monomer mixture in this cell, it was placed in a hot-air drying oven and kept at 75 ° C for 8 hours and 120 ° C for 1 hour to polymerize the monomer mixture, and subsequently cooled to room temperature. After cooling, the glass plates with a thickness of 10 mm that constitute the top and bottom of the cell were removed to obtain a transparent photochromic laminate. Table 1 shows the evaluation results. [Table 1]

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Claims (1)

Claims: 1. A photochromic laminate in which a layer of a crosslinked polymer containing a photochromic substance-containing (meth) acrylic acid alkyl ester unit as a main component is interposed between at least two transparent plates. . 2. A cell is formed by interposing a gasket between at least two transparent plates facing each other and clamping the outer periphery of the cell, and the inside of the cell is a (meth) acrylic acid alkyl ester monomer. The method for producing a photochromic laminate according to claim 1, wherein a mixed solution of a monomer having at least two unsaturated double bonds in one molecule and a photochromic substance is encapsulated and then cured by polymerization. 3. A transparent plate is provided on both inner surfaces of at least two flat plates facing each other, a gasket is interposed between the transparent plates, and the outer periphery is clamped to form a cell, and the inside of the cell is formed. After enclosing a mixed solution of a (meth) acrylic acid alkyl ester monomer, a monomer having at least two unsaturated double bonds in one molecule, and a photochromic substance, the mixture is polymerized and cured [claim 1 ] The manufacturing method of the photochromic laminated body of description.