JPH0456291B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a synthetic resin photochromic lens that has excellent surface hardness, abrasion resistance, durability, and photochromic performance. The safety of eyeglass lenses was reviewed in 1972 with the enactment of the US FDA standards (Standards for safety of eyeglasses), and safer synthetic resin materials began to be used as lens materials instead of inorganic glass. I'm getting old. In Japan, the share of plastic cleansing is increasing year by year, and is said to have already exceeded 30%. In addition to the safety, lightness, durability, and ease of processing that plastic materials have, it also has functions such as anti-reflection coating, hard coating, hard anti-reflection coating, cloud-proofing properties, and high refractive index resin. This is thought to be due to the fact that numerous manufacturers have conducted extensive research into imparting this and commercialized it one after another. On the other hand, diethylene glycol bisallyl carbonate (hereinafter referred to as CR-39) is the mainstream of plastic cleansing.
The market share of resin lenses in the United States is said to be approximately 50%, and growth has slowed since the market share reached 50%. This is CR
It is speculated that the CR-39 lens is more easily scratched compared to the glass of the -39 lens, and the other reason is that the CR-39 lens does not have a superior photochromic lens.
Currently, the only photochromic lens that changes color to blue is on the market, but there are problems with its functionality (light reduction rate, coloring speed, and fading speed). On the other hand, the overwhelming majority of consumer requests regarding the coloring of Photochromic lenses are for the lens to change from colorless to brown or gray due to absorption of light. In other words, it is no exaggeration to say that there are no satisfactory synthetic resin photochromic lenses. In addition, from a technological point of view, the wear resistance of plastic materials,
Research to improve durability and research on materials that exhibit photochromic performance have been conducted individually and many proposals have been made, but no research that comprehensively considers both has been conducted, and ,
A synthetic resin photochromic lens that simultaneously satisfies photochromic performance has not yet been established. Typical examples of stamping techniques for improving the wear resistance of plastic materials are JP-A-50-40674 and JP-A-51-
42752, JP 52-112698, JP 53-111336,
It is disclosed in JP-A-56-99263, USP-3986997, etc. On the other hand, the technology related to photochromic materials (lenses) is as follows: Japanese Patent Publication No. 45-12716, No. 45-28893, No. 1106-1972, No. 89179-1989, No. 51-1983
45541, JP 52-152887, JP 54-955, JP 54-110854, JP 55-121412, JP 57-
39244, Japanese Patent Publication No. 57-55747, Japanese Patent Application Laid-open No. 57-136645, etc. Photochromic performance can be imparted to plastic resin materials using these techniques by adding molecules that exhibit photochromic performance consisting of organic or inorganic compounds to the plastic material, by bonding them to polymer chains, or by thermally contacting them with them. Methods have been taken to either move the material or to laminate it in a resin, but in either case the wear resistance is poor and it is not satisfactory as a lens material. Further, the method of adding a photochromic material to the resin is not preferable in terms of the appearance of the lens. This is because eyeglass lenses generally have different thicknesses between the center and the outer periphery, so if photochromic molecules are uniformly distributed in the lens material, there will always be a concentration gradient in the light attenuation rate due to color development. Furthermore, when a casting method such as CR-39 is employed, most of the photochromic molecules are inactivated by commonly used peroxides such as diisopropyl peroxydicarbonate. The method of transferring photochromic molecules by contact makes it difficult to transfer them uniformly, and tends to cause unevenness and defects on the lens surface. JP-A No. 58-34437 describes a method of imparting photochromic functions by dispersing and dissolving photochromic substances in a solvent and impregnating the treated plastic substrate with SiO, SiO ₂ , Al ₂ O ₃ ,
A method of depositing _ZrO2 is disclosed. Although this technology is excellent in improving the various drawbacks mentioned above, problems remain in terms of wear resistance and heat resistance.
In other words, in terms of improving heat resistance, abrasion resistance, and impact resistance, silicon-based materials are preferred over those deposited with inorganic materials due to the large difference in coefficient of thermal expansion between the plastic base material and the vapor-deposited material, problems with adhesion, etc. It is a well-known technique in the eyeglass lens industry that a hard coat or a silicon-based hard coat and then a vapor-deposited antireflection layer made of an inorganic material are better. In addition, the present inventors previously proposed a synthetic resin photochromic lens using tetraalkyl silicate or the like instead of component B in the present invention (Japanese Patent Application No. 57-157852), but it had drawbacks in terms of pot life. Served. In view of the above points, the present inventors have developed a photochromic function that develops a brown color upon irradiation with light and reversibly returns to colorless in the dark, and has improved surface hardness, abrasion resistance,
As a result of research to obtain a synthetic resin photochromic lens with excellent durability, the invention described below was achieved. That is, the present invention is a synthetic resin photochromic lens characterized by being coated and cured with a coating composition containing the following A, B, and C as main components. A Silver halide (halogen is a halogen excluding fluorine) B Colloidal silica with a particle size of 1 to 100 millimicrons C General formula

[Formula] (where R ¹ is an organic group containing at least one selected from vinyl, amino, imino, epoxy, (meth)acryloxy, phenyl, and SH group, R ²
is hydrogen, a (halogenated) hydrocarbon group having 1 to 6 carbon atoms, R ³ is a hydrocarbon group having 1 to 5 carbon atoms, an alkoxyalkyl group, or an acyl group having 1 to 4 carbon atoms,
a is 0, 1 or 2, b is 0, 1 or 2, and a hydrolyzate of one or more silicon compounds represented by a+b≦2). Next, each component constituting the coating composition of the present invention will be described. Silver halide as component A may include silver bromide, silver iodide, silver chloride, and mixtures of two or more of these. A combination is preferred. Component B, colloidal silica with a particle size of 1 to 100 millimeters, refers to a product in which high molecular weight silicic acid anhydride is dispersed in a dispersion medium such as water, alcohol, or cellosol, and is produced by a well-known method and commercially available. It is something that exists. Particle sizes of 5 to 40 microns are particularly useful in the practice of this invention. B
This component is important for improving the wear resistance and durability of the coating. General formula of C component

The silicon compound represented by the formula is an essential component for improving the adhesion, flexibility, and abrasion resistance of the film. Specific examples include vinyltrimethoxysilane, vinyltriethoxysilane, and vinyltriacetoxysilane. , γ-aminopropyltrimethoxysilane, γ
-glycidoxypropyltrimethoxysilane, γ
-glycidoxypropyltriethoxysilane, γ
-glycidoxypropylmethyldimethoxysilane, β-glycidoxyethyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-(3,4-epoxycyclohexyl)ethyltriethoxysilane,
γ-(meth)acryloxypropyltrimethoxysilane, γ-(meth)acryloxypropylmethyldimethoxysilane, phenyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, phenyltriacetoxysilane, γ-chloropropyltrimethoxy Silane, β-cyanoethyltriethoxysilane, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane,
Tetrabutoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, phenylmethyldiethoxysilane, etc. There is. Hydrolysis of these silane compounds is
For example, in a mixed solvent such as water and alcohol,
It is carried out in a known manner in the presence of an acid. When the compound of component C is used without being hydrolyzed, the wear resistance is insufficient. Furthermore, when two or more types of silicon compounds are hydrolyzed and used, better results are often obtained by mixing them and simultaneously co-hydrolyzing them than by hydrolyzing them separately and then mixing them. Further, although hydroxyl groups purified by hydrolysis are present in a partially condensed form, this does not affect the effects of the present invention. In order to more effectively exhibit the photochromic properties of the present invention, it is preferable to add a trace amount of a metal oxide such as copper oxide, antimony oxide, or iron oxide. Also, if necessary, alkali metal salts of carboxylic acids such as sodium acetate, amine carboxylates such as ethanolamine acetate, quaternary ammonium carboxylates such as tetramethylammonium acetate, and triethylamine, glycine, pyridine, alkali hydroxides, etc. Condensation catalysts such as BF ₃ , Sncl ₄ , Sncl ₂ , Alcl ₃ or other Lewis acids, or epoxy curing catalysts such as Brainstep acid, aluminum chelate compounds, other metal chelate compounds, or ammonium perchlorate are used. and effective. Various solvents, surfactants, thixotropic agents, ultraviolet absorbers, antichlorination agents, and various polymers can be added for the purpose of improving coating work and imparting necessary properties as a paint. As the solvent or diluent, various solvents such as alcohols, ketones, esters, cellosolves, halogenated hydrocarbons, carboxylic acids, and aromatic compounds can be used, and one or more of these can be used as a mixed solvent. It is also possible. The composition of the present invention can be applied to a synthetic resin lens by a known method such as a dipping method, a spray method, a spin coating method, or a flow coating method. The synthetic resin lens coated in this manner is heated and dried to obtain a cured film.
Conditions such as heating temperature and heating time are determined in consideration of the characteristics of the resin, but a temperature of 60 to 150°C is usually applied. The thickness of the resulting cured film is preferably 1 to 30 μm; if it is less than 1 μm, satisfactory wear resistance cannot be obtained, and in order to maintain the required properties, photochromic materials must be used. I have no choice but to limit the amount. On the other hand, even if the thickness is 30μ or more, hardening cannot be expected by increasing the film thickness.
Cracks are also likely to occur. In order to improve the adhesion between the synthetic resin lens and the coating composition, it is useful in the practice of the present invention to pre-treat the lens surface with various primers, activated gas treatment, chemical treatment with acids, alkalis, etc. It is. The coating composition thus obtained is made of polycarbonate resin, acrylic resin, CR-39
The present invention can be applied to the surface of a lens made of a transparent resin such as resin or polystyrene to provide a photochromic lens made of a synthetic resin having excellent transparency, surface hardness, abrasion resistance, durability, and photochromic performance. The present invention will be explained in more detail below with reference to Examples, but the present invention is not limited thereto.
Note that parts in the examples indicate parts by weight. The coating was evaluated using the method shown below. Photochromic performance: Using Photochromic lens photochromic lens tester HE-223 (manufactured by Hasegawa Copy Co., Ltd.), those with an average light attenuation rate of 30% or more in the visible range in one test were considered good. Abrasion resistance: A load of 1 kg was applied with #0000 steel wool, and the surface was rubbed back and forth 10 times, and the degree of scratching was divided into the following grades and evaluated. A: There are almost no scratches. B: Some damage will occur. C: Significant damage will occur. Adhesion of the coating film: In the so-called cross-cut tape test, 10 parallel lines were made vertically and horizontally at 1 mm intervals on the coating surface using a knife, 100 squares were cross-cut, and cellophane adhesive tape was attached on top of the cross-cuts. After that, the tape was peeled off and the number of squares that did not peel off among the 100 squares was displayed. Hot water resistance: The state of the film was visually inspected after being immersed in boiling water for 1 hour. Heat resistance: The state of the film was visually inspected after being stored in a hot air drying oven at 120°C for 2 hours. Chemical resistance: After 24 hours of immersion in ethanol, acetone, 1% sulfuric acid aqueous solution, and 0.5% sodium hydroxide aqueous solution, the state of the film was visually inspected. Example 1 (1) Adjustment of hydrolysis of γ-glycidoxypropyltrimethoxysilane In a reactor equipped with a stirring device, 359 parts of isopropyl alcohol and 200 parts of isopropyl alcohol-dispersed colloidal silica (manufactured by Catalysts Kasei Kogyo Co., Ltd.) were added. Oscar 1432 (solid content concentration 30%), 236 parts of γ-glycidoxypropyltrimethoxysilane, and 0.3 part of silicone surfactant were added, and 81 parts of a 0.05 N nitric acid aqueous solution at room temperature was added all at once while stirring. Stirring was continued for an hour. Thereafter, stirring was stopped, and the mixture was aged at room temperature overnight. (2) Adjustment of elementary quantity and coating 30 parts of silver bromide with an average particle size of 50 mμ was added to the hydrolyzate obtained in (1), and mixed with a homogenizer.
The mixture was stirred at 20,000 rpm for 1 hour to disperse and form a paint.
This paint was applied to a plano lens made of CR-39 by the dipping method (pulling speed 20 cm/min) and cured by heating in a hot air drying oven at 80°C for 30 minutes and then at 120°C for 120 minutes. The thickness of the film after curing was 5μ. still,
The initial viscosity of the coating liquid measured by a B-type viscometer was 5.2 centipoise, and the viscosity after one month was 5.8 centipoise, and the liquid life was good. The properties of the obtained lens are shown in the table. Example 2 160 parts of methyl cellosolve, 118 parts of γ-glycidoxypropyltrimethoxysilane, 23 parts of methyltrimethoxysilane, 200 parts of methanol-dispersed colloidal silica ("methanol silica sol" manufactured by Nissan Chemical Co., Ltd. solid content concentration 30%) was charged into a reactor equipped with a rotor, and while vigorously stirring using a magnetic stirrer, a 0.05N acetic acid aqueous solution was added at once at room temperature, and stirring was continued for 1 hour. Stop stirring, 10
It was aged overnight at ℃. To this liquid were added 1 part of a silicone surfactant, 40 parts of silver bromide with an average grain size of 50 mμ, and 4 parts of acetylacetone zirconium, and the mixture was stirred with a homogenizer at 20,000 rpm for 1 hour to disperse and form a paint. The obtained coating liquid was immersed into polymethyl methacrylate sunglasses (pulling speed 20cm/
min) and dried and cured at 60°C for 1 hour and at 80°C for 5 hours. The thickness of the coating was 6.5μ. The liquid life of the paint was good for one month. The properties of the obtained lens are shown in the table. Example 3 280 parts of isopropyl alcohol, 200 parts of colloidal silica dispersed in methanol in a reactor equipped with a rotor
Part (Catalyst Chemical Industry Co., Ltd.) Oscar 1132 Solid content concentration 30
%), 165 parts of γ-glycidoxypropylmethyldiethoxysilane, and 0.3 parts of a silicone surfactant were added in this order and stirred. Then, while stirring at room temperature,
31 parts of 0.05N acetic acid aqueous solution was added and stirring was continued for 1 hour. Thereafter, stirring was stopped, and the mixture was aged at room temperature overnight. In the liquid obtained in this way, a sealing particle size of 50 mμ was added.
30 parts of silver bromide and 10 parts of silver iodide were added and stirred using a homogenizer at 20,000 rpm for 1 hour to disperse and form a paint. This paint was applied to polycarbonate sunglasses by the dipping method (pulling speed: 20 cm/min) and cured by heating in the same manner as in Example 1. The thickness of the film after curing was 5μ. The properties of the obtained lens are shown in the table. The life of the paint remained good even after one month. Example 4 In a reactor equipped with a rotor, 240 parts of isopropyl alcohol, 300 parts of water-acid colloidal silica (Catalyst Chemical Industry Co., Ltd., CataloidSN, solid content concentration 20%), γ
-Glycidoxypropyltrimethoxysilane 142
1 part, 41 parts of γ-methacryloxypropyltrimethoxysilane, and 0.5 part of a silicone surfactant were added in this order while stirring with a magnetic stirrer, and the stirring was continued for 2 hours. After the stirring was stopped, the mixture was aged at room temperature for one day and night. Add 40 parts of silver bromide with an average particle size of 50 mμ and 2 parts of stannous chloride to the above solution, and use a homogenizer to
The mixture was stirred at 20,000 rpm for 30 minutes to disperse and form a paint. Using the obtained paint, Hattori Seiko Co., Ltd.
It was coated and cured in the same manner as in Example 1 on a -6.00D lens under the trade name Hiroad. Film thickness is 7μ
A high index photochromic lens was obtained. The properties of the obtained lens are shown in the table. The pot life of the paint was good for one month.

【table】

Claims (1)

[Scope of Claims] 1. A synthetic resin photochromic lens characterized by being coated and cured with a coating composition containing the following A, B, and C as main components. A Silver halide (halogen is a halogen excluding fluorine) B Colloidal silica with particle size of 1 to 100 millimicrons C General formula [Formula] (However, R ¹ is vinyl, amino, imino, epoxy, (meth)acryloxy, phenyl and An organic group containing at least one selected from SH groups, R ² is hydrogen, a (halogenated) hydrocarbon group having 1 to 6 carbon atoms, R ³ is a hydrocarbon group having 1 to 5 carbon atoms, an alkoxyalkyl group, or an acyl group having 1 to 4 carbon atoms,
a is 0, 1 or 2, b is 0, 1 or 2, and a hydrolyzate of one or more silicon compounds represented by a+b≦2).