Plastic lens material, production process of the material, composition for plastic lens, plastic lens obtained by curing the composition, and production process of the plastic lens

Abstract

A plastic lens material comprising a compound in which a part or all of 1,4-cyclohexane dicarboxylate structural units are a cis structure; a production process of the material; a plastic lens composition containing the material; a plastic lens obtained by curing the composition; and a production process of the plastic lens. A plastic lens material free of changing into a white and turbid material during storage for a long period of time is provided.

Description

[0001] This application is an application filed under 35 U.S.C. .sctn.111(a) claiming benefit pursuant to 35 U.S.C. .sctn.119(e)(1) of the filing date of the Provisional Application 60 / 208,495 filed Jun. 2, 2000, pursuant to 35 U.S.C. .sctn.111(b).[0002] The present invention relates to a plastic lens material, a production process of the material, a plastic lens composition containing the material, a plastic lens obtained by curing the composition, and a production process of the plastic lens.[0003] More specifically, the present invention relates to a plastic lens material which can produce a plastic lens while preventing the generation of uneven dyeing and which can be used for a plastic lens composition capable of preventing damaging of a mold used for the cast polymerization; a production process of the material; a plastic lens composition containing the material; a plastic lens obtained by curing the composition; and a production process of the plastic lens.[0004] Recently, or...

AI Technical Summary

Benefits of technology

[0021] The present invention has been made as an attempt to improve the crystallinity of the diallyl ester oligomer compounds containing a cyclohexane dicarboxylate structure by taking notice of the problem that the compound becomes white and turbid when stored at normal temperature. Accordingly, the object of the present invention is to provide a plastic lens material, a production process of the material, a plastic lens composition containing the material, a plastic lens obtained by curing the composition, and a production process of the plastic lens, in which the effect of improving the releasability of a plastic lens from a mold and also the dyeability of the plastic lens as described in WO99 / 17137 and WO99 / 38899 can be more simply implemented.

[0023] As a result, it has been found that a plastic lens material free of occurrence of changing into a white and turbid material due to crystallization at room temperature can be produced by controlling the ratio of a cis structure to a trans structure in the cyclohexane dicarboxylate structural units contained in a diallyl ester oligomer compound containing cyclohexane dicarboxylate structural units.

[0091] If the amount of the material blended is less than 0.05 mass %, the effect of reducing uneven dyeing may not be brought out, whereas if the amount blended exceeds 30 mass %, the profitability is disadvantageously low, though there is no problem in the performance.

[0115] The constructive material of the mold used here may be a metal or glass. In general, the mold for plastic lenses must be cleaned after the casting and such cleaning is usually performed using a strong alkali solution or a strong acid. Unlike metal, glass is scarcely changed in the quality by the cleaning and furthermore, glass can be easily polished and thereby extremely reduced in the surface roughness, therefore, glass is preferably used.

Problems solved by technology

The plastic lens derived from polystyrene resin has a problem in that a sufficiently high value cannot be obtained with respect to the birefringence and light scattering, though the refractive index is high.

The plastic lens derived from polycarbonate resin is disadvantageously inferior in solvent resistance and scratch resistance, though the impact resistance are high.

In the plastic lens derived from polymethyl methacrylate resin, the refractive index is low and the impact resistance are not at a satisfactory level.

However, the plastic lens derived from polydiethylene glycol bis(allyl carbonate) resin has a problem in that when the lens is polymerized in a mold for lenses and then the cured product is separated from the mold, the mold is damaged.

At this time, a very great energy is released and occasionally even a shock may be caused.

More specifically, the glass mold is partly drawn out and cannot be used as a glass mold any more.

The loss caused by this usually reaches several % of the production yield of plastic lenses.

In order to decrease such damage to the mold, a slight amount of a mold-releasing agent is added in some cases, however, this adversely affects other properties of the lens, for example, adhesion of a scratch-resistant coating which is applied in the next step.

Accordingly, the use of a mold-releasing agent is not proper for solving this problem.

However, this technique is still not at a satisfactory level.

In addition, there is a problem in the weather resistance.

However, the diallyl ester oligomer compounds containing a cyclohexane dicarboxylate structure disclosed in these publications have a relatively high crystallinity and suffer from a problem that when stored at a normal temperature or less for a long period of time, the compound becomes white and turbid.

In such a case, if the compound is redissolved by raising the temperature using some means, the compound may be used as a raw material of a plastic lens without any problem, however, a fear still remains for possibilities that the compound structure changes due to excess heating or in turn the improvement effect intended by the addition of the compound decreases.

Furthermore, an extra process of heating the compound on use is necessary and the profitability is disadvantageously low in view of the energy required.

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