JPH0570524A - Optical resin - Google Patents

Abstract

PURPOSE:To obtain an optical resin excellent in optical properties such as refractive index and transparency and mechanical properties by polymerizing and curing a polymerizable composition containing a mixture obtained by an addition reaction among a compound of a specified formula, a dithiol compound and divinylbenzene. CONSTITUTION:An optical resin is obtained by polymerizing and curing a polymerizable composition containing a polymerizable mixture obtained by an addition reaction among a compound of formula I (wherein R1 and R2 are each H or CH3) (e.g. 2-hydroxy-1,3-diacryloxypropane), a dithiol compound of formula II (e.g. 1,4-benzenedithiol) and divinylbenzene. This resin has a refractive index of 1.55 or above, a high Abbe's number and low optical strain, excels in optical transparency, heat resistance, solvent resistance and impact resistance, has a low specific gravity, is capable of weight reduction, is easy in the control of its polymerization and curing, can give a cured resin easily subjected to various surface treatments, and is useful as the material of ophthalmic lenses.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical resin, and more particularly to an optical resin useful for plastic lenses for eyeglasses and the like, which are excellent in optical properties such as refractive index and transparency and various mechanical properties.

[0002]

2. Description of the Related Art In recent years, synthetic resin materials excellent in light weight, moldability, impact resistance and dyeability have been used as lens materials instead of inorganic glass. Known examples of the synthetic resin material include polymethyl methacrylate, polydiethylene glycol bisallyl carbonate, polystyrene, and polycarbonate. The polymethyl methacrylate and polydiethylene glycol bisallyl carbonate are excellent in lightness and impact resistance, but when used as a lens because of their low refractive index of about 1.49, a lens thicker than inorganic glass is required, It has a drawback that it is not suitable for high magnification and light weight. Also,
The polystyrene and polycarbonate have a high refractive index of about 1.58 to 1.59, but since they are thermoplastic resins, they have a problem that optical distortion due to birefringence is likely to occur during injection molding. There are drawbacks such as lack of resistance and scratch resistance.

Therefore, recently, some technical proposals have been made to improve these conventional drawbacks with a high refractive index. For example, JP-A-53-7787 discloses a copolymer of diethylene glycol biscarbonate and diallyl isophthalate, and JP-A-59-81318.
JP-A-59-1 discloses a copolymer of diallyl phthalate and unsaturated fatty acid alcohol benzoate.
Japanese Patent No. 91708 discloses a copolymer of di (meth) acrylate having bisphenol A and diallyl isophthalate with diethylene glycol bisallyl carbonate and the like.

However, the above-mentioned copolymer has a problem that the refractive index is as low as 1.52 to 1.56, and unreacted allyl monomer is likely to remain.

Further, Japanese Patent Application Laid-Open No. 57-28115 discloses that
As a copolymer of a styrene-based vinyl monomer and an unsaturated carboxylic acid heavy metal salt, JP-A-60-55007 proposes a copolymer of a halogen-substituted diallyl phthalate and a halogen-substituted allyl benzoate. Although the copolymer has a high refractive index of about 1.58 to 1.60, it uses a metal salt or an allylic monomer having a halogen-substituted aromatic ring, so that the specific gravity of the polymer is large, There is a drawback that the lens becomes heavy and the weight reduction is impaired.

Further, JP-A-55-13747 discloses a copolymer of halogen-substituted styrene, di (meth) acrylate having bisphenol A, a benzyl methacrylate-based monomer and a phenol methacrylate-based monomer. Japanese Patent No. 133211 proposes a polymer of a hydroxydi (meth) acrylate having an aromatic ring and a diisocyanate compound and a styrene monomer. In the case of the compound, the refractive index is around 1.60. However, it is difficult to control the polymerization reaction and has a large specific gravity, and there is a problem in weather resistance.

Further, JP-A-2-58001 and JP-A-2-289622 disclose a compound having two or more unsaturated groups in one molecule or divinylbenzene and two thiol groups in one molecule. An optical resin obtained by reacting with a compound having is disclosed. However, the above-mentioned optical resin has a problem that it is difficult to perform a surface treatment such as a hard coat, which is particularly important when it is put into practical use as a plastic lens for eyeglasses.

[0008]

SUMMARY OF THE INVENTION Therefore, the object of the present invention is to obtain various mechanical properties, heat resistance, solvent resistance, and resistance to a desired refractive index, transparency, etc. for plastic lenses or other optical resins. It is an object of the present invention to provide an optical resin which has excellent impact resistance, low specific gravity, low odor and excellent handling property when cured, and which is easy in reaction control and molding during polymerization and curing. Another object of the present invention is to provide an optical resin in which the resin after curing has excellent dyeability and which can be easily surface-treated such as a hard coat and an antireflection film.

[0009]

According to the present invention, a compound represented by the following general formula 3 (hereinafter referred to as compound A),

[0010]

[Chemical 3]

A compound represented by the following general formula (4) (hereinafter referred to as dithiol compound B)

[0012]

[Chemical 4]

An optical resin obtained by polymerizing and curing a polymerizable composition containing a polymerizable mixture (hereinafter referred to as a polymerizable mixture C) obtained by the addition reaction of divinylbenzene.

The present invention will be described in more detail below.

The polymerizable mixture C used as an essential component of the polymerizable composition in the present invention includes the compound A represented by the general formula 3, the dithiol compound B represented by the general formula 4, and divinylbenzene. Which is a mixture obtained by addition-reacting, and examples of the addition reaction product include a compound or a prepolymer in which a double bond in the compound A and / or divinylbenzene and a thiol group of the dithiol compound B are subjected to an addition reaction. And the like, but may contain unreacted compound A, dithiol compound B, and divinylbenzene.

Specific examples of the compound A used as a raw material component of the polymerizable mixture C include 2-hydroxy-1,3-diacryloxypropane and 2-hydroxy-
1,3-dimethacryloxypropane, 2-hydroxy-
1-acryloxy-3-methacryloxypropane, which can be used alone or as a mixture when used.

The dithiol compound B used as a raw material component of the polymerizable mixture C will be specifically listed below.
4-benzenedithiol and bis- (4-mercaptophenyl) -sulfide, which can be used alone or as a mixture when used.

As the divinylbenzene, p-
Divinylbenzene or m-divinylbenzene can be used alone or as a mixture.

The charging ratio of the compound A, the dithiol compound B and the divinylbenzene in carrying out the addition reaction is not particularly limited, but preferably 5 to 60% by weight of the compound A and 10 to 50% by weight of the dithiol compound B, Divinylbenzene is in the range of 20 to 60% by weight. If it is out of the above range, the refractive index, mechanical properties and dyeability of the resin after curing are deteriorated, and the surface treatment of a hard coat, an antireflection film and the like becomes difficult, which is not preferable.

To carry out the addition reaction, for example, in the presence of a catalyst or a basic catalyst such as triethylamine, an acid catalyst such as sulfuric acid, a catalyst such as a peroxide such as benzoyl peroxide, in the air or under a nitrogen stream. , Preferably 0-80
The reaction can be carried out at a temperature of 30 ° C. for 30 minutes to 48 hours.

Also, the above-mentioned polymerizable mixture C in the polymerizable composition.
The compounding ratio of is not particularly limited, but is preferably 20% by weight or more based on the entire polymerizable composition. If the blending ratio is less than 20% by weight, a sufficient refractive index cannot be obtained, which is not preferable.

In the present invention, examples of the monomer other than the polymerizable mixture C which can be used as the polymerizable composition component include, for example, styrene, p-methylstyrene, p-chlorostyrene, o-chlorostyrene, p. -Bromstyrene, o-bromostyrene, α-methylstyrene, vinyl acetate, vinyl propionate, methyl methacrylate, butyl methacrylate, methyl acrylate,
Ethyl acrylate, phenyl acrylate, phenyl methacrylate, benzyl acrylate, benzyl methacrylate, bromphenyl methacrylate, acrylonitrile, methacrylonitrile, 2,2-bis (4-
(Meth) acryloyloxyethoxyphenyl) propane, 2,2-bis (4- (meth) acryloyloxypolyethoxyphenyl) propane, 2,2-bis (4-
2'-hydroxy-3 '-(meth) acryloxypropoxyphenyl) propane, diethyleneglycol bisallyl carbonate, diallyl tetrachlorophthalate, diallyl phthalate, p-divinylbenzene, m-divinylbenzene, divinylbiphenyl, ethylene Glycol bis (meth) acrylate, diethylene glycol bis (meth) acrylate, dipropylene glycol bis methacrylate, propylene glycol bis acrylate
And triethylene glycol bis (meth) acrylate
And tetraethylene glycol bis (meth) acrylate
Polyethylene glycol bis (meth) acrylate
And bisphenol A bismethacrylate, diallyl tetrachlorophthalate, diallyl isophthalate, and allyl methacrylate can be preferably mentioned.

The high refractive index optical resin of the present invention can be prepared, for example, by photopolymerization or thermal polymerization or copolymerization of the polymerizable composition in the presence of a radical polymerization initiator. The radical polymerization initiator is 10
An organic peroxide or an azo compound having a time half-life temperature of 160 ° C. or lower can be used, and specifically, for example, benzoyl peroxide, diisopropyl peroxydicarbonate, t-butylperoxy-2-ethylhexanoate. , T-butylperoxypivalate, t-butylperoxydiisobutyrate, lauroyl peroxide, t-butylperoxyacetate, t-peroxyoctoate, t-butylperoxybenzoate, azobisisobutyronitrile and the like are used. In this case, they can be used alone or as a mixture. The amount of the radical polymerization initiator used is 10 parts by weight or less, particularly preferably 5 parts by weight or less, based on 100 parts by weight of the polymerizable composition.

To carry out the heat polymerization or copolymerization, for example, the polymerizable composition and the radical polymerization initiator are directly charged into a desired mold, and preferably 0 to 200 ° C., 1 to 4
It can be polymerized by heating for 8 hours. At this time, the polymerization system is preferably carried out in an atmosphere of an inert gas such as nitrogen, carbon dioxide or helium. In addition, before the polymerization, the polymerizable composition is, for example, 0 to 200.
After preliminarily polymerizing at 0.5 ° C. for 0.5 to 48 hours, it can be charged in a desired mold and post-polymerized.

Further, additives such as a UV absorber and a coloring preventing agent may be added to these polymerizable compositions as required. Further, for the purpose of improving the surface properties of the cured product, various surface treatments such as hard coating and antireflection film may be applied after the curing.

[0026]

INDUSTRIAL APPLICABILITY The optical resin of the present invention has a refractive index of 1.55 or more and a high Abbe number, has a small optical strain, and has optical transparency, heat resistance, solvent resistance and impact resistance. Is also excellent, and further, the specific gravity is small and the weight can be reduced.
In addition, reaction control during polymerization and curing is easy, and since various surface treatments such as hard coating and dyeing of the resin obtained after curing can be easily performed, lenses for glasses, camera lenses, optical materials, etc. It is useful as a plastic lens material or other optical resin material.

[0027]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

[0028]

Example 1 In a four-necked flask equipped with a stirrer and a nitrogen blowing tube, 5 g of 2-hydroxy-1,3-diacryloylpropane, 45 g of 1,4-benzenedithiol and divinylbenzene (manufactured by Tokyo Kasei Co., Ltd.) , Reagent) 50g
And 0.02 g of triethylamine as a catalyst
Was added and the mixture was stirred at room temperature for 6 hours to give a polymerizable mixture 1.
00g was obtained.

To 10 g of the obtained polymerizable mixture, 0.05 g of t-butylperoxybenzoate was added and mixed to obtain a monomer composition. Then, after charging the monomer composition into two glass molds, the monomer composition was placed in a constant temperature bath at 80 ° C., heated at a curing temperature of 80 ° C. for 6 hours, and further heated at 100 ° C. for 3 hours.
The temperature was raised to 0 ° C and finally heated at 100 ° C for 3 hours. Finally, an annealing treatment was performed at 100 ° C. for 2 hours to obtain a cured resin. The obtained cured resin was taken out of the mold, and the refractive index, Abbe number, b * value, hard coat adhesion, dyeability and heat resistance were measured according to the following methods. The results are shown in Table 2.

Refractive index and Abbe number: An Abbe refractometer (manufactured by Atago Co., Ltd.) was used, and measurement was carried out using a methyl iodide saturated solution as an intermediate solution.

B * value (yellowness): measured using a photometer model 1001 manufactured by Nippon Denshoku Industries Co., Ltd. The smaller this value, the smaller the yellowness and the better.

-Heat resistance: A sample having no deformation or discoloration in an oil bath at 110 ° C was rated as ◯, and a sample having deformation or discoloration was rated as x.

Hard coat adhesion: a commercially available dyeable silicone hard coat agent (trade name "TS-56-
T ", manufactured by Tokuyama Soda Co., Ltd., using the above resin (diameter 70 m
m, thickness 2 mm) dipping method (pulling speed 70 cm / min)
After coating and drying at room temperature for 15 minutes, 130 ℃
And heat treated for 1 hour. Then, the mixture was cooled to room temperature, 100 squares having a width of about 2 mm were drawn with a cutter knife, and adhesion and peeling were repeated 5 times using cellophane tape, and those with no peeling were marked with ◯, and those with peeling were marked with x.

Dyeability: Commercially available as a dye (various product names "HOYA COBALT BLUE", HOYA
(Manufactured by K.K.) was immersed in a 0.1% aqueous solution at 90 ° C. for 10 minutes, and what was visually dyed was marked with ◯, and that which could not be dyed was marked with x.

[0035]

Examples 2 to 9 Example 1 was repeated except that a polymerizable mixture was prepared in the same manner as in Example 1 except that the raw material components shown in Table 1 were used, and then the polymerizable composition shown in Table 2 was used. A cured resin was prepared in the same manner as in, and each measurement was performed. The results are shown in Table 2.

[0036]

Comparative Examples 1 to 3 Except that the raw material components shown in Table 1 were used,
A polymerizable mixture was prepared in the same manner as in Example 1, and then a cured resin was prepared in the same manner as in Example 1 except that the polymerizable composition shown in Table 2 was used, and each measurement was performed. The results are shown in Table 2.

[0037]

[Table 1]

[0038]

[Table 2]

Claims (1)

[Claims] 1. A compound represented by the following general formula 1, A compound represented by the following general formula 2 And an optical resin obtained by polymerizing and curing a polymerizable composition containing a polymerizable mixture obtained by addition reaction of divinylbenzene.