JPH0346801B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a synthetic resin lens copolymer having excellent light resistance and weather resistance. 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 been 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. At the same time, in order to meet market needs, the materials for synthetic resin lenses include diethylene glycol bisallyl carbonate (hereinafter abbreviated as CR-39), polycarbonate, polymethyl methacrylate, etc. 7789, JP-A-53-7790,
Unexamined Japanese Patent Publications 1983-41965, 1986-77686, 1983-
13747, Japanese Patent Publication No. 13747-15118, etc., there is a wide variety of methods. On the other hand, synthetic resins have superior properties compared to inorganic glass in terms of safety, lightness, dyeability, and processability, but are inferior in terms of weather resistance and light resistance. In order to overcome the above drawbacks, improve weather resistance and light resistance, and block UV rays that are harmful to the eyes, we generally use benzotriazole-based, benzopenone-based, cyanoacrylate-based, and salicylic acid ester-based ultraviolet absorbers and light stabilizers. is added to synthetic resin lenses. However, since these UV stabilizers are low molecular weight compounds, their UV absorption efficiency decreases after long-term use, leading to material deterioration and yellowing. (often ultrasonically cleaned). In view of the above points, an object of the present invention is to provide a synthetic resin lens that blocks harmful ultraviolet rays to the eyes, has good weather resistance and light resistance, and has long-term reliability. The synthetic resin lens according to the present invention comprises one or more radically polymerizable ultraviolet absorbers (first monomer) whose general formula is represented by [ ] [ ] [ ] and one or more radically polymerizable second monomers. It is obtained by copolymerizing with (In the formula _, R ₁ is hydrogen or a _methyl group _; is hydrogen or an alkyl group having 1 to 8 carbon atoms, R ₄ is hydrogen or a carbon number 1
~8 alkyl group or aryl group, _R5 is an alkyl group having 1 to 4 carbon atoms, X is hydrogen or chlorine,
Represents bromine, methoxy group, nitro group, and amino group. m represents 0-5, n represents 0-8, and p represents 0-2. M indicates metal, Pb, Zr, Ti, La, Ta,
There are Cu, Zn, Sn, Cr, and Tl. q represents the number obtained by subtracting 2 from the valence of the metal atom M. ) Weather resistance and light resistance are improved by using one or more first monomers whose general formula is represented by one of [] to [], but the optical properties, surface hardness, and impact resistance of the lens are improved. In order to satisfy lens characteristics such as hardness and solvent resistance, diethylene glycol bisallyl carbonate, diallyl isophthalate, or a radically polymerizable compound represented by any of the general formulas [] to [XI] must be used as the second monomer resistance. Must be used in combination with monomers. In carrying out the present invention, the composition ratio of the first monomer is determined by the degree of coloring of the polymer and its solubility in the second monomer. Crystals (powder) in the second monomer
There are many substances, but these monomers can be used in combination with a second monomer that dissolves them. In the present invention, a mixed solution of one or more first monomers, one or more second monomers, and a polymerization initiator is poured into a space created by two glass molds with a predetermined curvature and a gasket. It is formed by shaping and heating and curing. Polymerization initiators related to the present invention include common radical polymerization initiators such as azobisisobutyronitrile, benzoyl peroxide, diisopropyl peroxydicarbonate, lauroyl peroxide, and t-butyl isobutyrate.
It is used by mixing 0.03 to 3.0 parts by weight.
The concentration of the polymerization initiator used is determined in consideration of the composition ratio of the first monomer and the second monomer, reactivity, reaction rate control, etc. It is effective to use two or more types of polymerization initiators in consideration of reaction rate control. The present invention does not use the above-mentioned polymerization initiator, but uses ultraviolet light,
It can also be carried out by irradiation with radiation optical energy. The synthetic resin lens according to the present invention has optical properties,
It satisfies various properties necessary for lenses, such as surface hardness and impact resistance, and has the characteristic of dramatically improving weather resistance and light resistance, which could not be achieved with conventional low-molecular ultraviolet absorbers. . Furthermore, since the low-molecular-weight ultraviolet absorber is suspended in the lens material, a polymer containing a large amount of the ultraviolet absorber cannot be used as a lens material because its physical properties, particularly hardness, deteriorate. On the other hand, since the ultraviolet absorber, which is the first element according to the present invention, is incorporated into the lens material in a polymerized form, it has the advantage that physical properties do not deteriorate. Lenses polymerized in this manner are effective not only for eyeglasses but also as UV protection eyeglasses for arc welding and the like. Example 1 1 part by weight of 2,4-dihydroxy-4'-vinylbenzophenone, 65 parts by weight of O-chlorostyrene,
30 parts by weight of 2,2-bis(4-methacroyloxyethoxyphenyl)propane, 4 parts by weight of diethylene glycol bisallyl carbonate, and 0.5 parts by weight of benzoyl peroxide are mixed and stirred. While stirring this mixture at 30℃, reduce the viscosity.
Increased to 60CPS. Next, insoluble matters were removed from this mixed solution using a filter, and the filtrate was injected into a space formed by a gasket made of soft polyvinyl chloride and two glass molds having a predetermined curvature. next
4 hours at 30℃, 10 hours linearly from 30℃ to 50℃, 2 hours linearly from 50℃ to 70℃, 1 hour at 70℃
After thermal cycling at 80° C. for 2 hours, the gasket and glass mold were separated from the lens.
Further, this lens was post-cured at 100° C. for 2 hours to remove distortion inside the lens and obtain a lens with a predetermined power. The hardness, light resistance, weather resistance, impact resistance, heat resistance, and solvent resistance of the lenses manufactured in this way were investigated. The obtained properties fully satisfied the quality required for a lens. Detailed results are shown in Table 1. The test method for each characteristic was performed as follows. Pencil hardness: Based on JIS (K5400). Lightfastness: After 400 hours of fade meter testing, those with no surface roughness or coloring (yellowing) were considered good. Weather resistance: After 400 hours of weather meter testing, those with no surface roughness or discoloration (yellowing) were rated as good. Impact resistance: A steel ball drop test was performed on a flat plate with a center thickness of 2 mm according to FDA standards, and those that did not break were considered good. Heat resistance: heating at 120℃ for 2 hours, coloring, frequency change,
Those with no deformation were considered good. Solvent resistance: ethyl alcohol, acetone at 25℃
It was immersed for 24 hours, and those with no elution, surface roughness, cloudiness, or deformation were evaluated as good. Example 2 1 part by weight of ethyl P-vinyl-α-cyano-β-phenylcinnamate, 60 parts by weight of methyl methacrylate, 39 parts by weight of lead dimethacrylate, and 0.3 parts by weight of benzoyl peroxide were mixed and stirred, and the mixture of Example 1 and Lenses were cast-polymerized using the same procedure. The test results for the lens are shown in Table 1, and the finished lens fully satisfied the characteristics required for a lens. Example 3 2 parts by weight of methyl 4-vinylsalicylate, 75 parts by weight of diethylene glycol bisallyl carbonate, 20 parts by weight of N-vinylcarbazole, and 3 parts by weight of diisopropyl peroxydicarbonate were mixed and stirred, and a lens was prepared in the same manner as in Example 1. was synthesized. The test results of the finished lenses are shown in Table 1. The test results were good.

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Claims (1)

[Claims] 1. A first monomer consisting of one or more radically polymerizable ultraviolet absorbers whose general formula is represented by any one of [] to [], and diethylene glycol bisallyl carbonate, diallyl isophthalate, or A synthetic resin lens comprising a copolymer obtained by polymerizing one or more radically polymerizable second monomers having the general formulas [] to [XI]. (In the formula _, R ₁ is hydrogen or a _methyl group, ₃ represents hydrogen or an alkyl group having 1 to 8 carbon atoms, R ₄ represents hydrogen, an alkyl group having 1 to 8 carbon atoms, or an aryl group, R ₅
represents an alkyl group having 1 to 4 carbon atoms, and X represents hydrogen, chlorine, bromine, methoxy group, nitro group, or amino group. m represents 0-5, n represents 0-8, and p represents 0-2. M indicates metal, Pb, Zr, Ti, La, Ta,
There are Cu, Zn, Sn, Cr, and Tl. q represents the number obtained by subtracting 2 from the valence of the metal atom M. )