JPH06172457A - Composition for plastic lens - Google Patents

Abstract

PURPOSE:To obtain the subject composition having low optical strain and specific gravity and excellent in transparency, heat-resistance, impact resistance, surface hardness and processability by mixing a specific urethane compound with a specific acrylate at a specific ratio. CONSTITUTION:The objective composition is produced by mixing (A) a compound of formula I (R1 and R2 are H or methyl) such as the urethanization reaction product of isopropenyldimethylbenzyl isocyanate with 2-hydroxyethyl (meth)acrylate with (B) a compound of formula II (R3 and R4 are R1; (m) is 1 or 2) such as phenoxyethyl (meth)acrylate at a molar ratio (B/A) of >=0.3 and a ratio of [ (the total molar number of acryloyl groups of the components A and BX2)+(the total molar number of methacryloyl groups of the components A and B)]/(the molar number of the component A) of 1.5-3.0. A plastic lens can be produced by polymerizing and curing the composition.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a composition which is excellent in heat resistance, impact resistance, low water absorption, moldability, and is useful for a plastic lens capable of greatly shortening a polymerization time. is there.

[0002]

2. Description of the Related Art Plastic lenses are widely used in optical products because they are lighter in weight than glass lenses and can be easily molded. Currently, diethylene glycol bisallyl carbonate (CR-39) is most widely used as a resin for eyeglass lenses. This resin is excellent in transparency, impact resistance, light resistance, etc., on the other hand, it has a low refractive index of 1.49 to 1.50, and it is polymerized in a polymerization tank after being injected into a mold. 16
The disadvantage is that it takes more than time. Such a long polymerization time increases the manufacturing cost of the plastic lens because the polymerization tank has a long occupation time and a large number of molds are required.

Therefore, a method of carrying out polymerization in a short time by using active energy rays such as ultraviolet rays (Japanese Patent Laid-Open No. 3-231)
908, JP-A-63-289011, etc.) have been proposed. However, in these methods, although productivity is improved, a dedicated device for generating active energy rays for polymerization is required, and the component of the composition is composed of only a (meth) acrylate compound, It has a drawback that optical distortion called striae is likely to occur. Also,
Japanese Unexamined Patent Publication (Kokai) No. 2-84406 describes, as a high-hardness transparent resin, a resin having a high surface hardness that can be polymerized in a short time by thermal polymerization, and a lens made of the resin. However, the composition in this specification has a high surface hardness but a low impact resistance, and cannot be said to have sufficient performance as a lens.

[0004]

SUMMARY OF THE INVENTION The object of the present invention is to perform polymerization in a short time by using an existing apparatus, to obtain a small optical strain, excellent impact resistance, and physical properties equal to or higher than those of diethylene glycol bisallyl carbonate. It is to provide a composition for a plastic lens having.

[0005]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventors have found that a composition containing a compound having a specific structure is used, and a composition having a specific molar ratio is further used. As a result, they have found that the object can be achieved, and have completed the present invention. That is, the present invention relates to a component A represented by the following general formula (I) (Chemical formula 3) and the following general formula (I
I) The component (B) represented by the formula (4) is used in which the number of moles of the component B with respect to the number of moles of the component A is 0.3 or more and the number of moles of the component A is [(acryloyl group of the components A and B. Of the total number of moles x 2) + (the total number of moles of the methacryloyl groups of the component A and the component B)] is in the range of 1.5 to 3.0, and the composition for a plastic lens obtained by mixing, The present invention relates to a plastic lens obtained by polymerizing and curing a composition.

[0006]

[Chemical 3] (In the formula, R ₁ and R ₂ represent hydrogen or a methyl group)

[0007]

[Chemical 4] (In the formula, R ₃ and R ₄ are hydrogen or a methyl group, and m is 1 or 2.)

As a result of the study by the present inventors, a composition containing the compound having a specific structure of the present invention in a specific molar ratio is a composition which has good injection workability and polymerizes in a short time. The polymer has little optical distortion, is excellent in transparency, impact resistance, heat resistance, surface hardness and workability, and has a higher refractive index, higher surface hardness and lower than diethyleneglycol diallyl carbonate resin. It has a specific gravity and was found to be good as a plastic lens.

As the compound of the component A represented by the general formula (I) of the present invention, a urethanization reaction product of isopropenyldimethylbenzyl isocyanate and 2-hydroxyethyl (meth) acrylate or 2-hydroxypropyl (meth) acrylate is used. Is. Examples of isopropenyldimethylbenzyl isocyanate include 3-isopropenyl-α, α-dimethylbenzyl isocyanate, 4
-Isopropenyl-α, α-dimethylbenzyl isocyanate. Further, the urethanization reaction is a known method, that is, isopropenyl dimethyl benzyl isocyanate with 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and a catalyst (for example, di-n-butyltin laurate). The mixture is added dropwise under the condition of 30 to 90 ° C. and reacted.

The component B of the present invention has a high viscosity only with the component A and is difficult to inject into the mold. Therefore, in order to reduce the viscosity, the polymerization with the component A alone is insufficient. It is a component added for the purpose of completing the process. Furthermore, since the B component has a benzene ring and has an ethyleneoxy or propyleneoxy chain, it is possible to reduce the specific gravity without causing a decrease in the refractive index of the obtained lens, and the surface accuracy, It is also excellent in weather resistance and impact resistance. Specific examples of the B component monomer include phenoxyethyl (meth) acrylate, 2-phenoxy-1-methylethyl (meth) acrylate, 2- (2-phenoxyethoxy) ethyl (meth) acrylate, and 2- (2 -Phenoxy-1-methylethoxy) -1-methylethyl (meth) acrylate and the like.

The plastic lens composition of the present invention,
The range of the molar ratio for mixing the A component and the B component is 0.3 or more with respect to the number of moles of the component A and the number of moles of the component A [(A component And (the total number of moles of the acryloyl group of the component B x 2) + (the total number of moles of the methacryloyl group of the component A and the component B)] is 1.5 to 3.0.
Is. The number of moles of the B component relative to the number of moles of the A component is 0.
When it is 3 or less, the viscosity is high and injection becomes difficult, so that it is not suitable as a lens composition. Further, with respect to the number of moles of the component A,
[(Total number of moles of acryloyl groups of component A and component B x
2) + (the total number of moles of the methacryloyl groups of the A component and the B component)] is 1.5 or less, polymerization is incomplete, optical strain such as striae occurs, and the impact resistance of the lens is further deteriorated. And lowers heat resistance. Further, if it is 3.0 or more, it becomes difficult to control the polymerization, and in the intended short-time polymerization, that is, within 6 hours, more preferably within 4 hours, there is no pulse in the resin. It is not suitable for use as a lens because it causes a lot of optical distortion such as reasoning.

In the composition for a plastic lens of the present invention, in addition to the components A and B, an ultraviolet absorber may be added, if necessary, within a range that does not impair the effects of the present invention. As the ultraviolet absorber, general salicylate type, benzophenone type, benzotriazole type, hindered amine type, cyanoacrylate type and the like are used, but cyanoacrylate type is preferable for improving light resistance. Also, other,
Various additives such as an antioxidant, an anti-yellowing agent, a bluing agent, a pigment and a release agent may be added. The method for curing the composition for a plastic lens of the present invention is not particularly limited and any method can be adopted, but the thermal polymerization method is preferable because existing equipment can be used.

The radical polymerization initiator in the thermal polymerization is not particularly limited, and known benzoyl peroxide, p-chlorobenzoyl peroxide, lauroyl peroxide,
Acetyl peroxide, di-t-butyl peroxide, 1,1-di-t-butyl peroxy-3,3,5-
Trimethylcyclohexane, t-butylperoxypivalate, t-butylperoxy-2-ethylhexanoate, t-butylperoxybenzoate, bis (4-
t-butylcyclohexyl) peroxydicarbonate, diisopropylperoxydicarbonate, peroxides such as t-butylperoxyisopropylcarbonate, and one or a mixture of two or more azo compounds such as azobisisobutyronitrile, Total of A and B components 1
It is used in an amount of 0.005 to 5 parts by weight, preferably 0.1 to 3 parts by weight, based on 00 parts by weight.

The composition for plastic lenses of the present invention comprises
The above components are thoroughly mixed, filtered, and sufficiently defoamed under reduced pressure, and then polymerized and cured. The polymerization and curing method includes, for example, polyethylene, an ethylene-vinyl acetate copolymer, and two glass plate molds which are mirror-polished through a gasket made of vinyl chloride, and the composition of the present invention containing a polymerization initiator. It is injected and heat-treated.
Here, the mold includes glass and glass, glass and plastic plate, glass and metal plate, or a combination thereof. As the gasket, the above-mentioned soft thermoplastic resin may be used, and two molds may be fixed with a polyester adhesive tape or the like. Further, the mold may be subjected to a mold release treatment or the like. The polymerization temperature and the polymerization time when the composition for a plastic lens of the present invention is cured by a thermal polymerization method are determined by the radical polymerization initiator used, the frequency of the lens, etc., but at a temperature of 50 ° C to 130 ° C, It is possible to cure by raising the temperature and holding it within about 4 hours.

[0015]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. The parts in the examples represent parts by weight. Synthesis Example-1 2-isopropenyl-α, α-dimethylisocyanate was added to 201.3 parts while maintaining the liquid temperature at 40 ° C.
A mixture of 130.1 parts of hydroxyethyl methacrylate and 0.2 part of n-butyltin laurate was added dropwise and reacted. After completion of the dropping, the mixture was stirred at that temperature for 3 hours and left overnight to obtain urethane methacrylate monomer UM-I. Synthesis Example-2 In Synthesis Example-1, 116.1 parts of 2-hydroxyethyl acrylate was used instead of 130.1 parts of 2-hydroxyethyl methacrylate, and the same reaction was performed to obtain urethane methacrylate monomer UA-I. .

Synthetic Example-3 In Synthetic Example-1, 144.2 parts of 2-hydroxypropyl methacrylate was used instead of 130.1 parts of 2-hydroxyethyl methacrylate, and the same reaction was carried out to produce urethane methacrylate monomer UM-II. Got Synthesis Example-4 In Synthesis Example-1, 130.1 parts of 2-hydroxypropyl acrylate was used instead of 130.1 parts of 2-hydroxyethyl methacrylate, and the same reaction was performed,
Urethane acrylate monomer UA-II was obtained.

Example 1 UM-I, 82.9 parts (0.25 mol), phenoxyethyl acrylate 30.8 parts (0.16 mol), bis (4-t-butylcyclohexyl) peroxydicarbonate 0. 57 parts and 0.57 part of t-butylperoxy-2-ethylhexanoate were dissolved and mixed, filtered and defoamed, and then a center composed of two spherical glasses and a gasket of ethylene-vinyl acetate copolymer. Thickness 2.0 mm, outer diameter 7
It was poured into a 5 mm concave lens mold. The mold was placed in a polymerization oven, heated from 50 ° C. to 130 ° C. in 3 hours, kept at 130 ° C. for 1 hour and then cooled, and the cured product was taken out from the mold. The lens thus manufactured was evaluated by the following method, and the results are shown in (Table 1).
It was shown to.

Transparency: Visually judged, and those with high transparency without coloring or turbidity (○), those with slight coloring or turbidity (△), those with coloring or turbidity (×) did. Refractive index: Measured with an Abbe refractometer. -Heat resistance: measured by the TMA method. -Impact resistance: According to FDA standards, 16.3 g of an iron ball was dropped from a height of 127 cm and was not broken (o), and broken was (x). -Injection workability: The one that was easy to inject into the mold was (○), and the one that was difficult was (x). -Hardness: Measured with a pencil hardness meter. Striae: visually determined by a strain tester. Those with no striae were marked (○) and those with striae were marked (x).

Example 2 UM-II, 86.4 parts (0.25 mol), phenoxyethyl acrylate 19.2 parts (0.10 mol), bis (4-t-butylcyclohexyl) peroxycarbonate 0.53 Parts, and 0.53 parts of t-butylperoxy-2-ethylhexanoate were dissolved and mixed, filtered, defoamed, and then cured in the same manner as in Example 1, and the obtained lenses were evaluated. The results are shown in (Table 1).

Example 3 UA-I, 79.3 parts (0.25 mol), 2- (2-phenoxyethoxy) ethyl acrylate 23.6 parts (0.10 mol), bis (4-t-butylcyclohexyl) ) 0.51 part of peroxydicarbonate and 0.51 part of t-butylperoxy-2-ethylhexanoate are dissolved and mixed, filtered, defoamed and then cured in the same manner as in Example 1,
The obtained lenses were evaluated. The results are shown in (Table 1).

Example 4 UA-II, 82.9 parts (0.25 mol), phenoxyethyl methacrylate 24.7 parts (0.12 mol), bis (4-t-butylcyclohexyl) peroxycarbonate 0.54 Parts and 0.54 parts of t-butylperoxy-2-ethylhexanoate were dissolved and mixed, filtered, defoamed, and cured in the same manner as in Example 1, and the obtained lenses were evaluated. The results are shown in (Table 1).

Example 5 UM-I, 82.9 parts (0.25 mol), 2-phenoxy-1-methylethyl acrylate 41.2 parts (0.2
0 mol), bis (4-t-butylcyclohexyl) peroxycarbonate 0.62 parts, and t-butylperoxy-2-ethylhexanoate 0.62 parts are dissolved and mixed,
After filtration and defoaming, curing was performed in the same manner as in Example 1, and the obtained lens was evaluated. The results are shown in (Table 1).

Comparative Example 1 A lens was manufactured using only UM-I, but the viscosity was high and injection into a mold was difficult. Comparative Example 2 A lens was manufactured using only UA-I, but the viscosity was high and injection into a mold was difficult.

Comparative Example 3 UM-I, 82.9 parts (0.25 mol), phenoxyethyl acrylate 76.9 parts (0.40 mol), bis (4-t-butylcyclohexyl) peroxycarbonate 0.80. Parts and 0.80 parts of t-butylperoxy-2-ethylhexanoate were used for curing in the same manner as in Example 1, but the polymerization was runaway during the temperature rise.

Comparative Example 4 UM-I, 82.9 parts (0.25 mol), phenoxyethyl acrylate 52.9 parts (0.28 mol), bis (4-t-butylcyclohexyl) peroxycarbonate 0.68 And 0.68 parts of t-butylperoxy-2-ethylhexanoate were used and cured in the same manner as in Example 1 to evaluate the obtained lens. The results are (Table 1)
It was shown to.

Comparative Example 5 UM-I, 82.9 parts (0.25 mol), phenoxyethyl methacrylate 20.6 parts (0.10 mol), bis (4-t-butylcyclohexyl) peroxycarbonate 0.52. And 0.52 parts of t-butylperoxy-2-ethylhexanoate were used and cured in the same manner as in Example 1 to evaluate the obtained lens. The results are (Table 1)
It was shown to.

Comparative Example 6 UM-I, 82.9 parts (0.25 mol), benzyl methacrylate 33.5 parts (0.19 mol), bis (4-t)
-Butylcyclohexyl) peroxycarbonate 0.
A lens obtained by curing in the same manner as in Example 1 using 58 parts and 0.58 part of t-butylperoxy-2-ethylhexanoate was evaluated. The results are shown in (Table 1). Comparative Example 7 A commercially available CR-39 lens was evaluated in the same manner, and the results are shown in (Table 1).

[0028]

[Table 1]

Like Comparative Examples 1 and 2 in (Table 1), a lens cannot be manufactured without the B component. In addition, as in Comparative Examples 3 and 4, with respect to the number of moles of the A component, (the total number of moles of the acryloyl groups of the A component and the B component × 2) + (the total number of moles of the methacryloyl group of the A component and the B component) When the number) is 3.0 or more, striae are generated in the lens and the polymerization is runaway. Furthermore, as in Comparative Example 5, when the above-mentioned value is 1.5 or less, striae are generated and impact resistance is lowered. Further, as in Comparative Example 6, the compound in which the B component is similar to the B component of the present invention has a problem in impact resistance. The lens obtained using the plastic lens composition of the present invention is superior in refractive index, heat resistance, surface hardness, specific gravity, etc. to the lens CR-39 made of diethylene glycol diallyl carbonate shown in Comparative Example 7. ing.

[0030]

INDUSTRIAL APPLICABILITY The composition of the present invention has the advantage that the polymerization time can be greatly shortened in the production of plastic lenses. In addition, the obtained plastic lens has a low optical strain, a low specific gravity, and excellent transparency, heat resistance, impact resistance, surface hardness, and workability.

Front page continued (72) Inventor Kenichi Fujii 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Mitsui Toatsu Chemical Co., Ltd.

Claims (2)

[Claims] 1. A represented by the following general formula (I) (Chemical formula 1)
Ingredients and (In the formula, R ₁ and R ₂ each represent hydrogen or a methyl group) The component B represented by the following general formula (II) (In the formula, R ₃ and R ₄ are each hydrogen or a methyl group, m
Represents 1 or 2) The number of moles of the B component relative to the number of moles of the A component is 0.3 or more, and [(the total number of moles of acryloyl groups of the A component and the B component x
2) + (the total number of moles of the methacryloyl groups of the component A and the component B)] is in the range of 1.5 to 3.0, and the composition for a plastic lens is formed by mixing them. 2. A plastic lens obtained by polymerizing and curing the composition according to claim 1.