JPH01246501A - Plastic lens having high refractive index - Google Patents

Abstract

PURPOSE:To obtain a plastic lens having high refractive index, superior formability and dyeability, generating scarcely yellowing in a polymn. stage by using a copolymer of a diallyl ester having an aromatic ring with diethylene glycol bis(allyl carbonate) and a specified maleic diester. CONSTITUTION:A copolymer of a diallyl ester having an aromatic ring with diethylene glycol bis(allyl carbonate) and a maleic diester expressed by the formula I, is used for a material of the title plastic lens. In the formula I, each A<1> and A<2> is 1-12C alkyl group, 1-12C alkenyl group, 3-12C cycloalkyl group, etc.; X is a halogen atom.; each m and n is zero or an integer 1-5. Suitable proportion of each component is 10-100pts.wt. diethylene glycol bis(allyl carbonate) and 1-30pts.wt. maleic diester per 100pts.wt. diallyl ester. By this constitution, a plastic lens having high refractive index, superior formability and dyeability, and generating scarcely yellowing in a polymn. stage, is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a high refractive index plastic lens that has excellent moldability, transparency, and dyeability, and exhibits little yellowing during monopolymerization.

[Prior Art] In recent years, plastic lenses have rapidly become popular in place of glass lenses. This is because plastic lenses are lighter than conventional lenses, have better impact resistance and workability, and are easy to dye, so they are used in eyeglass lenses. Another point is that it enhances fashionability. in general,
The materials used in plastic lenses are transparent plastics made of homopolymers or copolymers such as diethylene glycol bis(allyl carbonate), methyl methacrylate, styrene, polycarbonate, and vinyl chloride, and diethylene glycol bis has particularly excellent transparency. (allylic carbonate) is said to be the most preferred.

However, diethylene glycol bis(allyl carbonate) polymer has a refractive index of about 1.50, while conventional glass lenses (crown glass) have a refractive index of 1.52.
The refractive index is lower than that of about 3, and as a result, concave lenses have the disadvantage that the peripheral thickness of the lens is larger than that of glass lenses, and this problem becomes especially noticeable as the lens power increases. .

Therefore, in order to solve these problems, efforts have been made to increase the refractive index of not only diethylene glycol bis(allyl carbonate) polymers but also various plastic lens materials, and many proposals have been made. For example, a high refractive index plastic lens made of a copolymer of diethylene glycol bis(allyl carbonate) and diallyl phthalate is disclosed in JP-A-53-7787. In addition, in general, to obtain high refractive index plastic,
It is known that the monomer contains an aromatic group, a halogen (excluding fluorine), a metal salt, etc., for example, an aromatic monomer t-form substituted with a bromine atom. A method of obtaining a high refractive index plastic lens using
This method is disclosed in Japanese Patent Application Laid-open No. 602, Japanese Patent Application Laid-Open No. 60-51706, Japanese Patent Application Laid-Open No. 61-64716, and the like.

[Problems to be Solved by the Invention] In the above-mentioned proposal for increasing the refractive index of wood for plastic lenses, a copolymer of diethylene glycol bis(allyl carbonate) and diallyl phthalate has a refractive index of 1.
．． Although it is possible to change the value from 50 to 1.57,
As the refractive index increases, moldability, impact resistance, dyeability, etc. decrease compared to diethylene glycol bis(allyl carbonate) homopolymer, and yellowing is particularly severe during polymerization, making it difficult to use as an eyeglass lens. There is a problem in that it is difficult to put into practical use.

Further, in the case of an aromatic monomer substituted with a bromine atom, the refractive index can be increased to around 1.60. However, the volumetric shrinkage associated with polymerization is large, and as a result, a phenomenon occurs in which the polymer molded product peels off from the mold.This phenomenon reduces the precision of the plastic lens.1 The surface becomes uneven, and the refractive index is uniform. will no longer be shown. Furthermore, it has various drawbacks such as being prone to striae, being inferior in dyeability to diethylene glycol bis(allyl carbonate) homopolymer, and having insufficient physical properties such as impact resistance.

The present invention was made in view of the above-mentioned problems, and its objectives are to improve moldability, dyeability, physical
The purpose of the present invention is to provide a high refractive index plastic lens made of a polymer having good chemical properties and little yellowing during polymerization.
Diethylene glycol bis(allyl carbonate),
Furthermore, the present invention was completed based on the discovery that a copolymer with maleic acid diester as the third component is suitable.

[Means for Solving the Problems] That is, the present invention provides a diallyl ester having an aromatic ring, diethylene glycol bis(allyl carbonate), and the following - formula % formula % (wherein A' and △2 may be the same or different) ,
Alkyl group having 1 to 12 carbon atoms, alkenyl group having 1 to 12 carbon atoms, cycloalkyl group having 3 to 12 carbon atoms X represents a halogen atom, m,
n represents 0 or an integer of 1 to 5. ) A high refractive index plastic lens made of a copolymer with a maleic acid diester represented by:

Examples of the diallyl ester having an aromatic ring in the present invention include diallyl phthalate, diallyl terephthalate, diallyl isophthalate, triadyl isocyanurate, and the like. These diallyl esters can be used not only alone but also in combination of two or more. Therefore, it is particularly preferable to use diallylisophthalate because it is less colored and has excellent impact resistance.

In addition, diethylene glycol bis(allyl carbonate) is a liquid monomer represented by the following formula, and by polymerizing it in the presence of a polymerization initiator, it has excellent transparency, high strength,
It becomes a hardened body with wear resistance. Therefore, it is currently the main material of plastic lenses, and the commercially available product is well known under the trade name "CR-39" (PPG Corporation).

Further, specific examples of the maleic acid diester represented by the above formula include diphenyl maleate, di-orthochlorophenyl maleate, di-orthobromphenyl maleate, di-parachlorophenyl maleate,
Di-metabromphenyl maleate, di(2) maleate
, 4-dichlorophenyl), parabromphenyl-orthobromphenyl maleate, benzyl-phenyl maleate, dibenzyl maleate, di-orthochlorobenzyl maleate, di-parachlorobenzyl maleate,
Di-orthobromobenzyl maleate, di-orthobrombenzyl maleate
Metabromobenzyl, orthochlorobenzyl maleate, benzyl maleate - orthobromobenzyl maleate, di(2,4-dichlorobenzyl) maleate, medyluphenyl maleate, dimethyl maleate, ethyl benzyl maleate, diethyl maleate, maleic acid. acid g n
-butyl, di(2-ethylhexyl) maleate, dinonyl maleate, cyclohexyl-phenyl maleate, allyl-benzyl maleate, diallyl maleate,
Examples include methallyl-benzyl maleate.

A diallyl ester having an aromatic ring according to the present invention.

When manufacturing a high refractive index plastic lens made of a copolymer of diethylene glycol bis(allyl carbonate) and maleic acid ester, the proportion of each used is 10 to 100 parts by weight of diethylene glycol bis(allyl carbonate) per 100 parts by weight of diallyl ester. part, preferably 30 to 80 parts by weight, and furthermore 1 to 30 parts by weight, preferably 2 to 20 parts by weight of maleic acid diester. If the amount of diethylene glycol bis(allyl carbonate) used is less than 10 parts by weight, the resulting lens will have poor physical and chemical properties such as surface hardness, impact strength, and weather resistance. On the other hand, if it exceeds 100 parts by weight, the physical and chemical properties will improve, but the refractive index will become low. If the amount of maleic acid diester used is less than 1 part by weight, yellowing of the lens becomes noticeable, while if it exceeds 30 parts by weight, it becomes extremely difficult to remove the lens from the mold in polymerization molding.

The method for manufacturing the plastic lens of the present invention is not particularly limited. For example, in the conventional casting molding method, the above-mentioned monomers are mixed, and a prepared solution prepared by adding a polymerization initiator used for polymerization curing by heating is injected into a mold, and heat treatment is performed. A method of polymerizing and curing is adopted. In such a casting molding method, a glass mold is used as the mold, and assembled with a resin gasket. After injecting the preparation solution prepared as described above into this mold, the injection port is sealed and heat-treated.

The polymerization initiator used for polymerization curing by heating is not particularly limited, but typical examples include diisopropyl peroxydicarbonate, di-secondary-butyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, etc. Peroxydicarbonate, diacyl peroxide such as decainolbar oxide, lauroyl peroxide, acetyl peroxide, tert-butyl peroxyisobutyrate,
Examples include alkyloxyperesters such as tert-butyl peroxy 2-ethylhexanate and tert-butyl peroxy bivalate, and azo compounds such as azobisisobutyronitrile.

Use these polymerization initiators! Although i cannot be absolutely limited, it is generally 0.05 to 8 tonne weight %, preferably 0.1 weight 5 width M %, based on the total amount of each monomer.

Moreover, photopolymerization can also be adopted as a method for manufacturing the plastic lens of the present invention. In this case, a photosensitizer is added to the mixture of each II mer, for example, as a typical example,
Adding benzoin, penzoin methyl ether, benzoin ethyl ether, benzophenone, acetophenone, etc. in an amount of 0.1 to 8% by weight based on the total amount of each monomer,
It is polymerized and cured by irradiation with ultraviolet lamps, mercury lamps, etc. Of course, the above-mentioned polymerization initiators may be used in combination here.

Furthermore, each 1ij 7. (When preparing a preparation solution by mixing the lenses, for example, anti-static IL agents, anti-coloring agents, ultraviolet absorbers, ill-forming agents, etc. It can be added without any problem.

The high refractive index plastic lens of the present invention obtained in this manner can be coated on its outer surface by a known surface treatment to impart antireflection, high hardness, scratch resistance, antifogging properties, etc., or by dyeing. Formation of a dyed layer, etc. can be suitably performed.

[Example] Next, the present invention will be explained in more detail with reference to Examples.

In the examples, the properties of the obtained high refractive index plastic lenses were evaluated by the following test method.

(1) Refractive index Based on Atago's refractometer.

(2) Transmittance The luminous transmittance measured with "ASC-Model 304" manufactured by Asahi Bunko Co., Ltd. was used.

(3) Impact resistance A lens with a center thickness of 2 mm was tested in accordance with FDA standards.

(4) Add 5.0 g of dyeing agent (“Asahibu Russell stain AG-13G”, manufactured by Asahi Glass Co., Ltd.) and 7.0 g of the dyeing agent (“AG coat dyeing aid”, manufactured by Asahi Glass Co., Ltd.) to 11 parts of water. The dispersed liquid was heated to 90° C., and the lenses were immersed in this dye bath for 3 minutes, and those showing the same dyeing properties as diethylene glycol bis(allyl carbonate) ttt monochrome aggregate were judged as passing.

(5) Surface hardness JIS-691 using Percoll hardness tester type 934-1
This was carried out in accordance with 1.

(6) Initial coloring By visual inspection, those with a slight degree of coloring were judged to have passed.

(7) Peeling between the mold and the mold After using a lens mold with a dioptric power of -5.00, 20 lenses were placed on the chassis, and the state of peeling between the mold and the mold was observed with the naked eye. The number of peeled sheets was defined as the number of sheets that peeled off from the mold.

(8) Striae +00 W ultra-high pressure mercury lamp irradiation device (manufactured by Ushio Electric Co., Ltd., “
A lens was held up to the parallel light rays emitted from the old model -100 model, 118-101A model), and those that showed no shadow in the lens image projected on the white screen were considered to be passed.

Example 1 A mixed solution consisting of 65 parts of diallyl isophthalate, 32 parts of diethylene glycol bis(allyl carbonate), 3 parts of diazyl maleate, and 2.5 parts of diisopropyl peroxydicarbonate was prepared. The mixed solution was injected into a mold assembled using two glass molds and a polyethylene gasket, and after sealing the injection port, it was heated from 30°C to 95°C for 18 hours.
It took a long time to heat the stomach. Thereafter, the polymerized and hardened lens was taken out from the mold and further heat treated at +20'C for 1 hour to obtain a lens with a power of -5.00. The characteristics of this lens were evaluated according to the IYi test method.

Its characteristics are shown in Table 1.

Examples 2 to 5 Lenses were obtained by cast molding in the same manner as in Example 1, except that the raw material composition was changed to the amounts shown in Table 1. The characteristics of this lens were evaluated.

Its characteristics are shown in Table 1.

Comparative Examples 1 to 3 Lenses were obtained by cast molding in the same manner as in Example 1, except that the raw material composition was changed to the amounts shown in Table 1. The characteristics of this lens were evaluated.

The results are shown in Table 1.

As shown in Table 1, in Examples 1 to 5, the copolymer with maleic acid diester has good moldability as a lens, has a high refractive index, and fully satisfies the required properties. ing. On the other hand, although Comparative Example 1 does not contain maleic acid diester, the initial coloration is significant. In addition, in Comparative Examples 2 and 3 made of bromine-substituted aromatic monomers, the refractive index of the copolymer was increased, but the volumetric shrinkage accompanying polymerization was large, and therefore peeling from the mold was difficult. It is clear that the lens is unsuitable as a lens because it is found to have striae and poor impact resistance and stainability.

[Effects of the Invention] The present invention solves various problems of conventional high refractive index plastic lenses, and provides excellent effects such as less yellowing during polymerization and good moldability and dyeability. do. Therefore, as a plastic lens, the center thickness and edge thickness of the lens can be reduced, and the appearance is also extremely excellent.

Claims (1)

[Claims] (1) Diallyl ester having an aromatic ring, diethylene glycol bis(allyl carbonate) and the following general formula ▲ Numerical formula, chemical formula, table, etc. ▼ (In the formula, A^1 and A^2 may be the same or different, Selected from alkyl groups with 1 to 12 carbon atoms, alkenyl groups, cycloalkyl groups with 3 to 12 carbon atoms, ▲ mathematical formulas, chemical formulas, tables, etc. ▼, ▲ mathematical formulas, chemical formulas, tables, etc. ▼, and X is A high refractive index plastic lens made of a copolymer with a maleic acid diester represented by (representing a halogen atom, m and n representing 0 or an integer of 1 to 5).