JPH0216481B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a synthetic resin lens with excellent characteristics, having a relatively high refractive index for a synthetic resin (1.59 to 1.61). Since the establishment of FDA standards in the United States in 1972, the safety of eyeglass lenses has been reviewed, and safer synthetic resins have come to be used as lens materials instead of inorganic glass. It's here. The shift from inorganic glass lenses to synthetic resin lenses is a worldwide trend, and in Japan, the share of synthetic resin lenses is increasing year by year. In particular, the proportion of lenses made of diethylene glycol bisallylicarbonate (hereinafter abbreviated as CR-39) resin is expected to have already exceeded 50% in the United States and France. Synthetic resin lenses have improved safety (they have high impact resistance, and even if they break, they do not break into minute pieces like inorganic glass, so there is less chance of damaging your eyes). It has many advantages compared to glass, such as being lighter, easier to process, and easier to color. On the other hand, CR-
39 has a low refractive index of 1.50 and weak mechanical strength, so the center thickness must be thicker than an inorganic glass lens even if the lens has the same diopter.This is especially true for minus lenses.
The edge thickness of lenses has become significantly thicker, and consumer demand for thinner lenses is extremely strong. Furthermore, organic materials such as polystyrene and polycarbonate having a relatively high refractive index have problems in scratch resistance, beading processability, heat resistance, and the like. In order to improve the above-mentioned drawbacks,
In Publication No. 13747, a copolymer of bisphenol A dimethacrylate or 22-bis(4-methacroyloxyethoxyphenyl)propane, etc. and styrene, or 0-chlorostyrene, phenyl methacrylate, benzyl methacrylate, etc. Although proposed, these copolymers have transparency,
Although it is excellent in terms of processability, etc., it is flammable, so there are still safety issues. To solve this problem, two-component copolymers of dimethacrylate or diacrylate compounds having a nuclear halogen-substituted aromatic ring and styrene, phenyl methacrylate, etc. have recently been developed, but these copolymers also have , due to the weak adhesion to the glass mold, the volume shrinkage during polymerization causes it to peel off from the glass mold, making it impossible to obtain the desired shape, resulting in an extremely low yield during polymerization, and anti-reflection coatings. Poor adhesion with inorganic vapor deposited films such as
Some manufacturing issues remain. In view of the above points, the present invention has a higher refractive index,
This was accomplished in order to realize a synthetic resin lens that fully satisfies the various properties required for a lens and solves manufacturing problems. That is, the purpose of the present invention is to have excellent transparency required for eyeglass lenses, have a refractive index of 1.6 or more in order to reduce the thickness of the lens, which is a latent demand of eyeglass wearers, and have a lens processability. The goal is to synthesize high-quality organic lenses. Another major objective of the present invention is to provide excellent weather resistance, light resistance, heat resistance, and
The aim is to synthesize organic lenses that are difficult to achieve. Another purpose is to improve the adhesion between glass molds and synthetic resin lenses, which is a major problem in lens casting. ) to prevent separation between the glass mold and the synthetic resin lens. In recent years, there has been a rapid increase in the demand for lens coatings, but materials deposited on lenses, such as SiO ₂ ,
One of the major objectives is to increase the adhesive strength with SioAl ₂ O ₃ etc. The copolymer of the lens according to the present invention contains 9 to 80 parts by weight of one or more monomers represented by the general formula [] and 20 to 80 parts by weight of one or more monomers represented by the general formula []. , 1 to 80 parts by weight of one or more monomers of mono- or dichloronaphthalene alkoxy acrylates, and 0.01 to 2.0 parts by weight of an ultraviolet absorber. It will be done. (In the formula, X is halogen or hydrogen excluding fluorine,
Y represents halogen excluding fluorine, R ₁ represents hydrogen or a methyl group, and m and n represent 0 or an integer from 1 to 4. ) When carrying out the present invention, the mixing ratio of each monomer and the ultraviolet absorber can satisfy the characteristics required for eyeglass lenses according to the ratios stated in the claims. In order to have specific properties, the monomers used [ ] [ ]
Although it depends on the type of monomer [], it is 30~
65 parts by weight, monomer [] is 25 to 70 parts by weight, mono- or dichloronaphthalene alkoxy acrylate (monomer []) is 5 to 50 parts by weight, ultraviolet absorber is
0.03-1.0% is suitable. Although it depends on the composition ratio of the monomer [], if the composition ratio of the monomer [] is less than 9 parts by weight, the impact strength of the lens decreases,
If it exceeds 80 parts by weight, heat resistance, chemical resistance, scratch resistance, and beading processability will be significantly reduced. Monomer []
If the composition ratio is less than 20 parts by weight, the heat resistance, chemical resistance, scratch resistance, and sanding processability will decrease, contrary to the monomer [ ], and if it exceeds 80 parts by weight, the impact resistance will decrease. decreases, and the characteristics required for the lens cannot be satisfied.
When the composition ratio of monomer [] is less than 1%, the adhesive strength between the glass mold and the lens is weak and the two are separated, resulting in an extremely low yield during polymerization. If the amount exceeds 80 parts by weight, the heat resistance, scratch resistance, and abrasion processability of the lens will decrease. If the concentration of the ultraviolet absorber is less than 0.01 parts by weight, weather resistance and light resistance will be extremely reduced, and if it exceeds 2.0 parts by weight, yellow coloration will be visible and the commercial value will decrease. The ultraviolet absorbers used in the present invention include benzophenone-based, benzoliazole-based, cyanoacrylonitrile-based, salicylate-based, and bis(2,2,6,6-tetramethyl-4-piperidyline) represented by the formula []. Sebacate There are UV absorbers. A polymerization initiator is added to a monomer [ ] [ ] [ ] and an ultraviolet absorber into a space created by two glass molds having a predetermined curvature of the present invention and a gasket, and the mixture is heated. However, lenses can also be formed by ultraviolet polymerization or radiation polymerization. In addition, RIM (Reaction Injection) can be achieved by selecting the type and amount of polymerization initiator.
Lenses can also be made by the molding method (molding), and are not limited to the casting method. Polymerization initiators related to the present invention include benzoyl peroxide, diisopropyl peroxydicarbonate, lauroyl peroxide, t-butyl peroxyneodecanoate, etc., and 0.03 to 3.0 parts by weight of an organic peroxide may be mixed therein. used by The type and concentration of the polymerization initiator used are determined in consideration of the composition, reactivity, reaction rate control, etc. of the mixture of monomers [ ] [ ] [ ]. The synthetic resin lens according to the present invention is characterized by improved weather resistance, light resistance, scratch resistance, heat resistance, flame retardance, and productivity that could not be achieved with conventional high refractive index resins. More specifically, halogen was introduced into the benzene ring of monomer [] to increase the refractive index. For example, 2,2-his(4-methacroyloxy), which is bromine introduced into 2,2-bis(4-methacroyloxyethoxyphenyl)propane,
3,5 dibromophenyl) propane has a refractive index of
Improved from 1.56 to 1.60. In addition, plastic lenses are resistant to sparks from grinders and welding, and are loved by people involved in these industries, but the introduction of halogen has greatly improved their resistance and heat resistance, making them excellent as safety glasses. It became a lens.
Furthermore, by adding monochloronaphthalene ethoxy dimethacrylate and an ultraviolet absorber, the refractive index was improved compared to those without these additions, and the weather resistance and light resistance were improved several times. In addition, especially by adding mono- or dichloronaphthalene alkoxy acrylates, the adhesive strength between the glass mold and the synthetic resin lens during polymerization was increased, and the yield during polymerization was dramatically improved. Specifically, this is because the polymerization system undergoes a volumetric contraction of about 11% during polymerization. In other words, when mold-polymerizing a negative strength type lens, for example a -6.00D lens, if the adhesive force between the glass mold and the lens is weak, it will not be able to follow the volumetric contraction, and the glass mold and lens will separate. happens. The incidence of this phenomenon is reduced from about 40% to 5% by adding mono- or dichloronaphthalene alkoxy acrylates.
%. Preferred mono- or dichloronaphthalene alkoxy acrylates include monochloronaphthalene ethoxy dimethacrylate, monochloronaphthaline methoxy dimethacrylate and dichloronaphthaline methoxy diacrylate. Furthermore, the adhesive strength between the lens and the inorganic deposited substance such as SiO ₂ SiO ₂ or Al ₂ O ₃ was increased, and the quality of the coating film was improved. Examples of the present invention are shown below. Example 1 50 parts by weight of 0-chlorostyrene, 2,2-bis(4
-Methacroyloxyethoxy, 3,5-dibromphenyl)propane 40 parts by weight, monochloronaphthalene ethoxydimethacrylate 10 parts by weight, 2-
(2′-hydroxy-5′methylphenyl)benzotriazole 0.4 parts by weight, lauroyl peroxide
Mix and stir 0.4 parts by weight. While stirring this mixture at 30°C, the viscosity was increased to 80 cps. Next, insoluble matter from this mixed solution was removed with a filter, and the oral fluid was injected into a space made by a gasket made of soft polyvinyl chloride and two glass molds. The gasket was then thermally cycled for 4 hours at 30℃, 10 hours linearly from 30℃ to 50℃, 2 hours linearly from 50℃ to 70℃, 1 hour at 70℃, and 2 hours at 80℃. and the glass mold was separated from the lens. According to this method, the incidence of peeling between the glass mold and the synthetic resin lens was 4% for a -6.00D lens. Furthermore, this lens was post-cured at 100°C for 3 hours to remove distortion inside the lens. The refractive index of the lens manufactured in this way,
Tamazuri processability, hardness, impact resistance, weather resistance, light resistance,
Solvent resistance and heat resistance were measured. The obtained lens had a refractive index of 1.604, and other characteristics sufficiently satisfied the characteristics required for a lens. Details are shown in Table-1. Furthermore, 3μ of silicon oxide was vapor-deposited on the obtained lens, and the coating film quality (film adhesion) of the obtained lens was investigated. The adhesion of the film was superior compared to conventional ones. The results are shown in Table-1. The test method for each characteristic was performed as follows. Refractive index: Measured using an Atspe refractometer. Machinability: Grinding is possible with a diamond edger for lens processing, and those with a clean surface are considered good. Pencil hardness: Based on JIS (K5400). Impact resistance: A steel ball drop test was conducted on a flat plate with a center thickness of 2 mm according to FDA standards, and those that did not break were considered good. Light resistance: After 200 hours of weather meter testing, those with no surface roughness or coloring (yellowing) were considered good. Light resistance: After 200 hours of fade meter testing, those with no surface roughness or coloring (yellowing) were considered good. Heat resistance: It was heated at 120°C for 2 hours and was judged as good if there was no coloration, change in frequency, or deformation. Solvent resistance: It was immersed in ethyl alcohol and acetone at room temperature for two days and nights, and was evaluated as good if there was no elution, surface roughness, cloudiness, or deformation. Polymerization yield: A rate of peeling between the glass mold and lens of 10% or less was considered good. Coating film quality: Lenses on which 3 μm of silicon oxide was deposited were left at 70°C for 3 hours, and those with no peeling or cracking were rated as good. Example 2 60 parts by weight of styrene, 30 parts by weight of 2,2-bis(4-methacroyloxy, 3,5-dibromphenyl)propane, 10 parts by weight of monochloronaphthalene methoxy dimethacrylate, 2-hydroxy, 4-
After mixing and stirring 0.5 parts by weight of methoxybenzophenone and 0.2 parts by weight of diisopropyl peroxydicarbonate, lenses were cast and polymerized in the same manner as in Example 1. As with Example 1, the finished lens was able to fully meet the characteristics required for eyeglass lenses. Details are shown in Table-1. Example 3 20 parts by weight of 0-chlorostyrene, 40 parts by weight of 2,2-bis(4methacroyloxyethoxy, 3,5 dibromphenyl)propane, 40 parts by weight of dichloronaphthalene methoxy diacrylate, 2-
(2′-hydroxy-5′methylphenyl)benzotriazole 0.3 parts by weight, lauroyl peroxide
A lens was synthesized in the same manner as in Example 1 by mixing and stirring 0.6 parts by weight. The test results of the completed lens are shown in Table 1, and it fully satisfied the characteristics required for the lens. The abbreviations for composition (monomer) in Table 1 are as follows. O-Clst: Orthochlorostyrene Br ₄ BMEPP: 2,2-bis(4-methacroyloxyethoxy3,5-dibromophenyl)propane CNEDMA: Monochloronaphthalene ethoxy dimethacrylate CNMDMA: Monochloronaphthaline methoxy dimethacrylate DCNMDA: Dichloronaphthaline mexidi Acrylate HMBP: 2-(2'-hydroxy, 5'methylphenyl)benzotriazole St: Styrene HMB: 2-hydroxy 4-methoxybenzophenone CR-39: Diethylene glycol bisallyl carbonate Ca: Polycarbonate BMEPP: 2,2-bis( 4-Methacroyloxyethoxyphenyl)propane BPDMA: Bisphenol A dimethacrylate [Table]

Claims (1)

[Claims] 1. 9 to 80 parts by weight of one or more monomers represented by the general formula [], 20 to 80 parts by weight of one or more monomers represented by the general formula [], or one of dichloronaphthalene alkoxy acrylates
1 to 80 parts by weight of monomers or more, and an ultraviolet absorber
A synthetic resin lens material comprising a radical copolymer of a monomer mixture comprising 0.01 to 2.0 parts by weight. (In the formula, X is halogen or hydrogen excluding fluorine,
Y is a halogen excluding fluorine, R ₁ is hydrogen or a methyl group, and m and n are 0 or an integer from 1 to 4. )