JPS60217301A - Plastic lens having high refractive index - Google Patents

Abstract

PURPOSE:To obtain a resin for plastic lens having high refractive index by polymerizing a specified amt, of a mixture consisting of two specified components having 0.5-2.0 molar ratio of NCO/OH with a specified amt. of a vinyl monomer having 1.55 refractive index. CONSTITUTION:20-100wt% mixture of an isocyanate compd. having >=2 functionality and molar ratio NCO/OH adjusted to 0.5-2.0 with a vinyl monomer having an OH group and expressed by the formula (wherein R is methyl or H), or an addition reaction product thereof is mixed with 0-80wt% vinyl monomer having >=1.55 refractive index of its polymer, and a reaction between the isocyanate group and an OH group is proceeded to completion by the addition of an addition reaction catalyst. Then, the reaction product is poured together with a polymerization initiator into a mold, polymerized by heating to obtain a plastic lens having high refractive index.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a plastic lens with excellent properties such as high refractive index, transparency, and impact resistance.

[Prior art]

Compared to glass lenses, plastic lenses have the advantage of being highly safe when used in eyeglass lenses due to their light weight, good processability, and impact resistance. Resins for plastic lenses that are in practical use today include polymethyl methacrylate resin, polycarbonate resin, diethylene glycol bisallyl carbonate styrene resin, and the like. Among these, polymethyl methacrylate resin and diethylene glycol bisallyl carbonate resin are widely used as plastic lenses for eyeglasses for vision correction. Polymethyl methacrylate resin has particularly excellent transparency and beautiful appearance, and also has good performance in terms of weather resistance, impact resistance, etc., and is inexpensive. However, it has drawbacks such as insufficient surface hardness, heat resistance, and chemical resistance.

Diethylene glycol bisallyl carbonate resin improves the drawbacks of polymethyl methacrylate resin and is most commonly used as a plastic lens for vision correction glasses.

However, polymethyl methacrylate resin and diethylene glycol bisallyl carbonate resin both have a refractive index of 1.49 to 1.50, and when this resin is used as a corrective lens, the disadvantage is that the lens will be thicker than a glass lens. There is.

This is particularly noticeable when the lens power increases.

Particularly in recent years, there has been a desire for plastic lenses to be smaller, smaller, and thinner, and there has been an increasing need for resins for plastic lenses that have a high refractive index that makes this possible.

[Purpose of the invention]

The present invention was arrived at as a result of repeated studies to meet these demands.

Therefore, an object of the present invention is to provide a resin for plastic lenses that has a high refractive index, is strong, and has a low polymerization shrinkage rate.

[Invention II, @) That is, the present invention relates to a high refractive index plastic lens formed by molding a polymer obtained by vinyl polymerizing 20 to 100% by weight of component A and 80 to 80% by weight of component B. It is something.

Component A is a mixture of the following components (■) and (◎) in which the NGO10H molar ratio is adjusted to 0.5 to 2.0, or an addition reaction product thereof.

■ Isocyanate compound with two or more functionalities ◎ General formula (1
) Vinyl monomer (1) containing a hydroxyl group (in the formula, R represents a methyl group or hydrogen) On the other hand, component B is a vinyl monomer whose polymer has a refractive index of 1.55 or more. It is.

The component used in the present invention is a bifunctional or higher-functional isocyanate compound that reacts with the hydroxyl group in the component to form a urethane bond, and by introducing this urethane bond, the impact resistance and bending required for eyeglass lenses can be improved. Improve elasticity etc.

Examples of bifunctional or more functional isocyanate compounds include the following.

Hexamethylene diisocyanate, isophorone diisocyanate, 2.2.4-trimethylhexamethylene diisocyanate, dicyclohexylmethane diisocyanate, lysine diisocyanate methyl ester, xylylene diisocyanate, tolylene diisocyanate,
Bis(incyanatomethyl)cyclohexane, 4,4
'-Diisocyanate compounds such as diphenylmethane diisocyanate, and trifunctional or higher functional isocyanate compounds such as biuret-forming reaction products of hexamethylene diisocyanate, reaction adducts of hexamethylene diisocyanate and trimethylolpropane, and ethyl 2-isocyanate. , 6-diycyane 5-monotoethylhexanoate, 1,6.11-undecane triisocyanate, reaction adduct of isophorone diisocyanate 1 and trimethylpropane, reaction adduct of silylene diisocyanate and trimethylolpropane , a reaction adduct of bis(isocyanatomethyl)cyclohexane and trimethylolpropane.

Particularly preferred among the above isocyanate compounds are:
xylylene diisocyanate, bis(isocyanatomethyl)cyclohexane, isophorone diisocyanate,
2-isocyanate ethyl-2,6-diincyanate ethylhexanoate and the like.

The component ◎ used in the present invention is a monomer having a xenyl group in its molecule, and is an essential component for obtaining a strong lens with a high refractive index. Specific examples include 3-(2-xenyloxy)-2-hydroxypropyl acrylate and 3-(2-xenyloxy)-2-hydroxypropyl methacrylate compounds.

-〇- The vinyl monomer as component B is necessary to copolymerize with component A to improve the various performances required for eyeglass lenses, and the refractive index of the polymer is 1.55 or more. It is.

Specific examples of vinyl monomers include styrene, chlorostyrene, dichlorostyrene, bromostyrene, iodostyrene, divinylbenzene, tribromophenyl methacrylate, tribromophenyl acrylate, pentabromophenyl methacrylate, tribromophenoxyethyl methacrylate, Nylcarbazole acrylate, Jetoxy-3,5-dibromphenyl)propane, 2,2-bis(4-acryloxyethoxy-3,5-
dibromphenyl)propane, 2-(4-methacryloxy-3.5-dibromphenyl)-2-(4-hydroxy-3.5-dibromphenyl)propane, diallyl phthalate, diallyl isophthalate, dimethallylchlorene chlorendate, ethyl diacrylate, benzyl acrylate, etc.

Among the above vinyl monomers, styrene, chlorostyrene,
Particularly preferred are bromstyrene, dibromstyrene, tribromophenyl methacrylate, tribromophenoxyethyl methacrylate, divinylbenzene, and mixtures thereof.

The amounts of component (■) and component (◎) to be used can be selected within the range such that the molar ratio of the NGO group in component (■) to the OH group in component (◎) is 0.5 to 2.0, but preferably NGOlo)I=
It is 0.5 to 1.5. Outside this range, the mechanical properties and thermal properties of the lens tend to deteriorate, and the machinability and polishability tend to be poor.

The vinyl monomer can be used in an amount of 0 to 80% by weight, but it is preferable to use an appropriate amount depending on the reactivity and physical properties. For example, if it exceeds 80% by weight, mechanical properties and machinability become poor. If it is less than 20% by weight, it will be difficult to obtain a high refractive index, so 30 to 70% by weight is preferable.

The method for producing plastic lenses using components ■ and ◎ and vinyl monomers of the present invention will be explained using the cast polymerization method. After completing the reaction between the group and the hydroxyl group, a polymerization initiator is added, the mixture is poured into a mold, and the mixture is heated and polymerized.

The heating temperature varies depending on the type of polymerization initiator, but distortion of the lens can be minimized by first conducting the reaction at a relatively low temperature (for example, 30 to 50°C) and gradually increasing the temperature as the reaction progresses to polymerize slowly. This is preferable in this respect.

As a reaction initiator, dibutyltin dilaurate, 1,
2,2,6,6-bentamethyl-4-hydroxypiperidine, stannath octoate, dimethyltin dichloride, and the like. The amount used is 0 per 100 parts by weight of the resin component.
．． 01 to 3.0 parts by weight is preferred.

Various known polymerization initiators can be used. For example, diisopropyl peroxydicarbonate, benzoyl peroxide, -butyl peroxide, dicumyl peroxide, 1,1'-azobiscyclohexane carbonate, 1-t-butylazo-1-cyanocyclohexane,
Good examples include t-butylperoxyisopropyl carbonate. The type and amount of the polymerization initiator used are determined by considering the monomer components, ◎ components, vinyl monomer mixture composition, reactivity, reaction rate control, etc., but generally the resin component 0.01 to 5.0 parts by weight per 100 parts by weight is suitable.

The lens in the present invention is a transparent plate through which light is transmitted and refracted, and includes convex/lens and concave lenses for eyeglasses and other optical equipment, and is particularly suitable for use as a lens for eyeglasses.

(Effects of the Invention) The synthetic resin lens according to the present invention provides a plastic lens that is stronger, colorless and transparent, and has a high refractive index (for example, a refractive index of 1.60 or more and an Abbe number of 30 or more) compared to conventional plastic lenses. Furthermore, since the shrinkage rate during molding polymerization is small, the phenomenon of separation between the glass mold and the lens does not occur, and a lens with beautiful homogeneity can be obtained.

The synthetic resin lens of the present invention can be subjected to known techniques such as antireflection, high hardness, abrasion resistance, improved chemical resistance, and antifogging properties.

The present invention will be explained in more detail with reference to Examples below. Note that the refractive index in the example is a value at the D line with a wavelength of 5892.9.

Example 1 Xylylene diisocyanate 12.0% by weight 3-(2
-xenyloxy)-2-hydroxypropyl acrylate 38.0% by weight Chlorstyrene (0 position/p position -6
5/35) 1100 pp of dibutyltin dilaurate as an NGO-OH reaction catalyst was added to the 50% by weight mixture and heated at 50°C for 2 hours. After that, it was cooled to room temperature, and di-
0.1% by weight of t-butyl peroxide was added.

This adjustment liquid was colorless and transparent and had a low viscosity, and could be easily cast into a lens mold consisting of a glass mold and a polyethylene gasket.

Polymerization was carried out stepwise from 60°C to 110°C.
I completed it in 0 hours.

After the polymerization was completed, the polymer was gradually cooled and released from the mold. The obtained resin was tough, colorless and transparent, had a high refractive index np of 1.60, and an A bbe number of 30.

Moreover, the specific gravity was small and lightweight at 1.21.

Example 2 Xylylene diisocyanate 12.0% by weight 3-(2
-xenyloxy)-2-hydroxypropyl acrylate 38.0% by weight Chlorstyrene (0 position/p position = 6
5/35) After dissolving a mixture of 25.0% by weight and 25.0% by weight of tribromophenoxyethyl methacrylate at 50°C, 1100pp of dibutyltin dilaurate was added as an NGO-OH reaction catalyst, and 50% by weight was added.
℃ for 2 hours. After that, it was cooled to room temperature, and diisopropyl peroxydicarbonate 50 was added as a polymerization initiator.
0 ppm and 0.1% by weight of di-t-butyl peroxide were added, mixed, and poured into a lens mold. This liquid mixture was colorless and transparent and had low viscosity.

The polymerization reaction was solidified by heating at 30° C. for 5 hours and 40° C. for 5 hours, and then the temperature was raised stepwise from 50° C. to 110° C. over 30 hours to complete.

The obtained cured product is colorless and transparent, tough, and has a refractive index of np.
was 1.61, and the Abbe number was 01.54.

Example 3 After thoroughly mixing 12% by weight of xylylene diisocyanate, 38% by weight of 3-(2-xenyloxy)-2-hydroxypropyl acrylate, and 50% by weight of p-bromustyrene, 1100 pp of dibutyltin dilaurate was added as an NCO-OH reaction catalyst. , and reacted at 50°C for 2 hours. Thereafter, 0.1% by weight of t-butylperoxyisopropyl carbonate was added as a polymerization initiator. This adjustment liquid was colorless and transparent, had low viscosity, and could be easily poured into lens molds.

The polymerization reaction was carried out in the same manner as in Example 1, and a colorless, transparent and tough resin was obtained.

13- The refractive index np of the resin was as high as 1.61, the Abbe number was -30, and the specific gravity was 1.38.

Patent applicant Higashi Shikikai Co., Ltd. 14-

Claims (1)

[Scope of Claims] (A) 20 to 100% by weight of a mixture consisting of the following components ■ and ◎, or an addition reaction product thereof, in which the molar ratio of NC010H is adjusted to 0.5 to 2.0 02-functional or higher isoleanate compound ◎ General A vinyl monomer (1) containing a hydroxyl group represented by formula (I) (in the formula, R represents a methyl group or hydrogen) and (B) a vinyl monomer whose polymer has a refractive index of 1.55 or more A high refractive index plastic lens made of a polymer obtained by polymerizing 0 to 80% by weight of a polymer.