JPH02167320A - Optical material - Google Patents

Abstract

PURPOSE:To provide a colorless transparent optical material having low specific gravity and excellent impact resistance and consisting of a novel resin having high refractive index and produced by the radical polymerization of a polyfunctional (meth)acrylate, (alpha-methyl)styrene and an unsaturated acrylic compound at specific ratios. CONSTITUTION:The objective resin having high refractive index can be produced by the radical polymerization of (A) 5-94.5wt.% of a polyfunctional (meth) acrylate of formula I or II [R1, R2 and R4 are H or CH3; X is group of formula III or IV (R3 is H, OH, etc.; l is 2-14), etc.; R5 is q-valent saturated aliphatic hydrocarbon group which may contain ether, etc.; q is 2-6], (B) 5-94.5wt.% of styrene and/or alpha-methylstyrene and (C) 0.5-40wt.% of an unsaturated nitrile (the sum of A-C is 100wt.%). The component A is e.g. diethylene glycol di(meth) acrylate.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an optical material made of a novel high refractive index resin that is low specific gravity, colorless and transparent, and has excellent impact resistance.

<Prior Art> Materials used to manufacture optical components such as lenses, prisms, optical waveguides, and disk substrates must be colorless and transparent. As an alternative material, transparent synthetic resins are being used in an expanding range of applications as organic optical materials due to their light weight, impact resistance, moldability, and dyeability.

Transparent synthetic resins used as optical materials are required to have various properties, among which the refractive index has an extremely important effect. For example, when used as a lens, in order to obtain a lens with the same focal length, a transparent synthetic resin with a high refractive index allows the lens to be made much thinner than a material with a low refractive index. The use of thin lenses has the advantage of reducing the volume of space occupied by the lenses in the optical assembly, making the optical device lighter and smaller.

In order to obtain a highly durable optical material for the housing, it is desirable that the impact strength is also high.

Conventionally, diethylene glycol bisallyl carbonate resin, polymethyl methacrylate, polycarbonate, etc. are generally known as resins used as plastic lens materials, but diethylene glycol bisallyl carbonate resin and polymethyl methacrylate have a refractive index of 1.49 to 1.49. Because of its small value of 1.50, when these resins are molded into plastic lenses, they have the disadvantage that the center thickness, edge thickness, and curvature become larger than inorganic optical glass lenses. Although polycarbonate has a high refractive index of 1.58 to 1.59, it tends to generate birefringence during molding and has drawbacks in optical uniformity. Furthermore, since polymethyl methacrylate and polycarbonate are thermoplastic resins with a non-crosslinked structure, the resins fuse during cutting or polishing, making them difficult to use in fields that require such processing, such as lenses for precision optical equipment, It was not satisfactory as an optical element or eyeglass lens material.

In order to improve the above-mentioned drawbacks of thermoplastic resins, a method of producing a resin having a crosslinked structure using ethylene glycol dimethacrylate as a crosslinking agent has been known (Japanese Patent Application Laid-open No. 4964G91). Resins obtained using ethylene glycol dimethacrylate have poor impact resistance.

JP-A No. 62-34102 discloses an example of using a styrene derivative in which the aromatic ring is substituted with a halogen as a high refractive index component, but the use of this material increases the specific gravity and reduces the light resistance. It has the disadvantage of being bad.

<Problems to be Solved by the Present Invention> The purpose of the present invention is to provide an optical material made of a high refractive index/low dispersion resin that is colorless and transparent, has excellent heat resistance, and impact resistance, and has a low specific gravity. be.

Means and Effects for Solving the Problems In view of the current situation, the present inventors have made intensive studies and found that a monomer component having a specific composition is polymerized in the presence of a radical polymerization initiator. We have discovered that the resin solves the above problems, is colorless and transparent, has excellent heat resistance, impact resistance, low specific gravity, high refractive index, and low dispersion, and is suitable as an optical material. This has led to the completion of the present invention.

That is, the present invention is a polymerizable monomer [■] consisting of a lai't or 2 m or more of a polyfunctional (meth)acrylate represented by the following general formulas (1) to (2) [■] 5 to 94.5 weight percent, Polymerizable monomer [II] consisting of styrene and/or α-methylstyrene 5 to 94.5% by weight and polymerizable monomer CI [[) consisting of unsaturated nitrile 0.5 to 40% by weight (However, the total of the polymerizable monomer components is 100% by weight.) Consisting of a high refractive index resin with low specific gravity and excellent impact resistance obtained by radical polymerization of the polymerizable monomer component. It relates to optical materials.

(Note) General formula (1) % formula % [In the formula, R1 and R8 are each independently H or R,
is H%CH, or 0H11, m is an integer of 2 to 14, and n is an integer of 4 to 14. ). ] General formula 2) (wherein, R4 is H or CH, R, represents K [a saturated aliphatic hydrocarbon group which may contain ether, alcohol, or ester on the child side q, and q is 2 to 6 ) The polymerizable monomer [■] used in the present invention is not particularly limited as long as it is represented by the general formula (1) or (2), and includes, for example, diethylene glycol di(meth)acrylate, Triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, nonaethylene glycol di(meth)acrylate, tetradecaethylene glycol di(meth)acrylate,
Dipropylene glycol di(meth)acrylate, nonapropylene glycol di(meth)acrylate, butanediol di(meth)acrylate, pentanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, hexanediol di(meth)acrylate , alkylene glycol di(meth)acrylates such as dodecanediol di(meth)acrylate; trimethylolpropane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate; ) acrylate, dipentaerythritol tri(meth)acrylate, trimethylolethane tri(meth)acrylate, etc., and one stack or two or more of these may be used.

The polymerizable monomer [II] used in the present invention is styrene and/or α-methylstyrene, each of which is used singly or as a mixture of 2 m.

The polymerizable monomer (lit) used in the present invention is acrylonitrile and/or methacrylonitrile.

These are used alone or as a mixture of two.

The polymerizable monomer component used in obtaining the optical material of the present invention may consist only of polymerizable monomers (1), [II, 1 and CI[[], but if necessary, Other polymerizable monomers (IV) may be used in the copolymerization component for the purpose of imparting other physical properties. Other usable polymerizable monomers [IV]
It is not particularly limited as long as it can be radically copolymerized with polymerizable monomers (1), (II) and/or (I [I), and it can be used with polymerizable monomers (II) and (III). In addition to monofunctional monomers that do not fall under the category of monofunctional monomers and polyfunctional monomers that do not fall under the polymerizable monomer (1), polymerizable polymers collectively referred to as oligomers can be used. Specific examples of such polymerizable monomers [IV] include methyl methacrylate, butyl methacrylate, cyclohexyl methacrylate), 4-
t-Butylcyclohexyl methacrylate, 2,3-dibromopropyl methacrylate, phenyl (meth)acrylate, benzyl (meth)acrylate, 2-methacryloyloxymethylthiophene, 3-methacryloyloxymethylthiophene, 2-(2-methacryloyloxyethyl) )thiophene, 2-tricyclo(5,2,
1,02°6]-3-decenyloxyethyl methacrylate, methyl-2-chloroacrylate, methyl-2-
Bromoacrylate, cyclohexyl-2-chloroacrylate, cyclohexyl-2-bromoacrylate,
2-Tricyclo(5,2,1,0)-3-decenyloxyethyl 2-chloro≠acrylate, ethylene glycol di(
Monofunctional or polyfunctional such as meth)acrylates.

Evaluation of (meth)acrylic acid esters; allyl benzoate, diallyl phthalate, diethylene glycol bisallyl carbonate, 2,2-bis(4-allyloxycarbonyloxyethoxy-3,5-dibromophenyl)furopane, 2,2-bis Allyl esters such as (4-allyloxy-3,5-dibromophenyl)propane, allyl carbonates, allyl ethers; epoxy (meth)acrylates, polyester (meth)acrylates, urethanes (
Mention may be made of reactive oligomers such as meth)acrylates.

In the present invention, the polymerizable monomer [III] imparts a crosslinked structure to the high refractive index resin, and therefore has excellent heat resistance and is less likely to cause fusion or clogging during cutting or beading. It is used to obtain a heat-resistant, high-refractive-index optical material that does not have any particles attached to it. In order to express such characteristics, the amount of the polymerizable monomer (1) used is 5 to 94.5% by weight, preferably 10 to 90% by weight of the polymerizable monomer component. I am in charge. If the amount is less than 5% by weight, the crosslinking density will be low and the effect on improving heat resistance, cutting workability, beading workability, impact resistance, etc. will be small), 94.
If the amount exceeds 5% by weight, the refractive index of the resulting resin will decrease.

The polymerizable monomer [II] is used to impart a high refractive index to the resulting resin. In order to sufficiently express such characteristics, the amount of polymerizable monomer (II) used should be 5 to 94.5% by weight in the polymerizable monomer component, preferably 10 to 94.5% by weight. 90 weight class.

If the amount is less than 5-m coefficient, the contribution to the change in the refractive index of the resulting resin will be small, and if the amount exceeds 94.5% by weight, the crosslinking density will be small, and the heat resistance, cutting workability, beading workability,
The effect on improving impact resistance etc. is small.

The snowballing monomer [■] is used to dramatically improve the impact resistance of the resulting high refractive index resin. In order to fully express these characteristics, polymerizable monomer (I[
The usage amount of [) is 0.5 to 40ff in the polymerizable monomer component.
ii%), preferably 2-30M.

If the amount is less than 0.5% by weight, the effect on improving the impact resistance of the resulting high refractive index resin will be small, and if the amount exceeds 40% by weight, the heat resistance of the resulting resin will be low.

The polymerizable monomer OV) is used to add various properties other than those described above to the resulting high refractive index resin. For example, among the above polymerizable monomers [IV], (meth)acrylic esters are used as polymerizable monomers [III] to arbitrarily adjust the refractive index, heat resistance, moldability, etc. of the resulting high refractive index resin. ], (II) and (III), and is preferably used in an amount of 1 to 50% by weight in the polymerizable monomer components. Allyl esters, (meth)allyl esters, allyl carbonates, and allyl ethers are useful in controlling the polymerization reaction, and are particularly effective in increasing the production yield in cast polymerization. It is preferably used in an amount of 1% to 30% by weight, preferably 0.5 to 20% by weight. Reactive oligomers such as epoxy (meth)acrylate, polyester (meth)acrylate, and urethane (meth)acrylate not only have the effect of reducing shrinkage during polymerization, but also improve production yield in cast polymerization. In order to improve the effect, it is preferably used in an amount of 1 to 50% by weight, more preferably 5 to 40% by weight, based on the polymerizable monomer component.

The high refractive index resin that is effective as an optical material of the present invention is a polymeric resin that contains polymerizable monomers [III], [II] and [■] as essential components, and optionally contains a polymerizable monomer [IV]. It is obtained by radical polymerization of monomer components.

There are no particular restrictions on the method of seven radical polymerizations (although conventionally well-known methods can be employed, specific examples include: (1) a method of heating and polymerizing a polymerizable monomer component in the presence of a radical polymerization initiator; .

■ A method in which polymerizable monomer components are polymerized with ultraviolet light in the presence of a photosensitizer.

■ A method of electron beam polymerization of polymerizable monomer components.

etc. can be mentioned.

Method (2) is the most common method, and the equipment is simple and the radical polymerization initiator is relatively inexpensive.

In the case of method (2), the curing speed is fast and the polymerization time can be shortened.

In the method (2), since polymerization can be performed even in the absence of a radical polymerization initiator or a photosensitizer, it is also possible to reduce the amount of impurities mixed into the high refractive index resin.

In the case of method (2), the polymerization method is not particularly limited, and conventionally known methods such as bulk polymerization, solution polymerization, suspension polymerization, etc. can be used. Among these methods, bulk polymerization is preferable for manufacturing lenses because cast polymerization can be used to form a shadow in a desired shape.
For example, a polymerizable monomer component to which a radical polymerization initiator has been added is poured into a glass mold, and heated to 30 to 60°C.
A specific example is a method in which polymerization is carried out by gradually raising the temperature from .

Further, a high refractive index resin can also be produced by a reaction injection molding method by appropriately selecting the type and amount of the polymerization initiator used. In cases other than cast polymerization, a step of shading into a desired shape is required after polymerization. Examples of radical polymerization initiators that can be used during polymerization include peroxides such as benzoyl peroxide, acetyl peroxide, di-t-butyl peroxide, diisopropyl peroxydicarbonate, and t-butyl peroxy-2-ethylhexanoate. Things and 2゜2'-
Azobisisobutyronitrile, 2,2'-azobis(2
, 4-dimethylvaleronitrile), and 1,1'-azobis(cyclohexane-1-carbonitrile). One stack or two or more of these are usually used as a necessary aging accelerator in an amount of 0.01 to 10% by weight, or 0.05 to 5% by weight, based on the polymerizable monomer component. It can be used and used.

Polymerization conditions cannot be determined unambiguously because they are affected by the type of polymerizable monomer, ui or ratio, and type of polymerization initiator, but in general, polymerization is started at a relatively low temperature and then the temperature is slowly raised. A suitable polymerization method is to carry out post-polymerization and curing at a high temperature upon completion of polymerization. However, since the polymerization time varies depending on various conditions, it is preferable to determine the optimal time according to these conditions in advance, but in general, the polymerization time is 2 to 40 minutes.
It is preferable to select conditions such that polymerization is completed within a certain amount of time.

In the case of methods (1) and (2), it is usually preferable to employ bulk polymerization by casting. However, method (2) requires the presence of a photosensitizer. For example, in the method (■), a photosensitizer is blended into the polymerizable monomer component and irradiated with ultraviolet rays; in the method (2), the polymerizable monomer component is irradiated with an electron beam. Yes, it can be easily made into a high refractive index resin. At this time, examples of photosensitizers that can be used in method (2) include benzoin,
Benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, 2-hydroxy-
2-benzoylpropane, benzyl dimethyl ketal,
For the azobisisobutyronito polymerizable monomer component, o,
It can be used in the range of oi to 10 weight ratios, preferably 0.05 to 8 weight ratios.

In the present invention, which of the methods ① to ② is used may be appropriately selected depending on the desired performance of the optical material made of the high refractive index resin obtained, and in some cases, a plurality of methods may be combined. .

The optical material of the present invention may appropriately contain known additives such as ultraviolet absorbers, antioxidants, drip-proofing agents, colorants, and the like. These additives may be blended in advance into the polymerizable monomer component before polymerization, or may be blended into the high refractive index resin after polymerization by a method well known to those skilled in the art.

The optical material of the present invention uses a high refractive index resin produced by the above procedure. For example, among the production methods described in detail above, those using the cast polymerization method have the t'! ! Alternatively, the optical material of the present invention can be obtained by subjecting the surface to an appropriate treatment. Moreover, the optical material of the present invention can be obtained by shaping the material by other methods into an appropriate shape and, if necessary, further subjecting the surface to an appropriate treatment.

<Effects of the Invention> Since the optical material of the present invention uses a polymerizable monomer component containing polymerizable monomers (1), (II) and polymerizable monomer (III) as essential components, it is colorless. It is made of a low specific gravity, high refractive index resin that has excellent transparency and impact resistance, as well as excellent heat resistance and cutting workability.

Therefore, the optical material of the present invention has a high refractive index, is lightweight, colorless and transparent, and has excellent impact resistance, heat resistance, and machinability, and is therefore suitable for use in, for example, lenses, prisms, optical fibers, and optical waveguides. , optical discs, films, and the like.

<Example> Hereinafter, the present invention will be specifically explained with reference to Examples.

The method for evaluating physical properties in each example is as follows.

[Colorless transparency]

The degree of coloring of a 1.5B thick sheet polymer obtained by cast polymerization was determined by visual observation.

[Refractive index and Abbo number]

The refractive index of a small piece of sheet-like polymer having a thickness of 1.5 ax obtained by casting the polymer was measured using an Abbe refractometer, and the Abbe number was determined from a dispersion table.

[Total light transmittance]

A sheet-like polymer having a thickness of 1.5 JIm obtained by casting was measured using a turbidity meter.

[Cutting workability]

A sheet-like polymer having a thickness of 1.5 mm obtained by casting with heavy metal casting was cut with a diamond cutter, and the presence or absence of cracks, cracks, fusion, etc. on the cut surface at that time was observed. No cracks, cracks,
Items with no fusion etc. are marked with a circle. For other defective products, defective points were indicated.

〔Heat-resistant〕

The cast polymer sheet with a thickness of 1.5 mm was placed in a hot air dryer at 100° C. for 3 hours, and deformation such as warping was observed during this time. Those in which no deformation was observed were marked with an O mark. For other defective products, defective points were indicated.

〔Pencil hardness〕

Measured according to JIS K 5400.

[Shock resistance (lens)]

Evaluation was made according to ASTM F 659. That is, a steel ball f of wg was dropped onto a lens having a center thickness of Tcm from a height of Hcm, and the lens that did not break was designated as WXH/Tc.

[Stainability]

The lens was immersed for 10 minutes in hot water (85° C. or higher) in which a disperse dye (disperse brown) and a carrier agent were dissolved, and the dyed state was observed. Items that could be dyed with even color were marked with an O mark. For other defective products, defective points were indicated.

〔exterior〕

Visually check hue, transparency, and optical surface condition 1i3! Based on the results, those that were colorless and transparent and in good surface condition were labeled as "good."

Example 1 50 parts by weight of tetraethylene glycol dimethacrylate, 40 parts by weight of styrene, 10 parts by weight of acrylonitrile, 0.1 part by weight of 2,2'-azobis-2,4-dimethylvaleronitrile and 2-(2-hydroxy- A mixture of 0.11 parts of 5-methylphenyl)benzotriazole was poured into a mold consisting of two glass plates and a silicone rubber gasket, kept at 50°C for 6 hours, and then heated for 1
Polymerization was carried out by raising the temperature at 10° C. over 16 hours. The obtained high refractive index resin [1] was colorless and transparent. Table 1 shows the physical properties of this high refractive index resin as an optical material.

Example 2 2. Diisopropyl peroxydicarbonate 0 in place of 2'-azohis-2,4-dimethylvaleronitrile b
．． The same procedure as in Example 1 was carried out except that 2 parts by weight was used. The obtained high refractive index resin [2] was colorless and transparent. Various physical properties of this high refractive index resin as an optical material are also shown in Table 1.

Example 3 A mixture of 50 parts by weight of tetraethylene glycol dimethacrylate, 40 parts by weight of styrene, 10 parts by weight of acrylonitrile and 2.0 parts by weight of benzoin isopropyl ether was poured into a mold consisting of two glass plates and a gasket made of silicone rubber. Then, ultraviolet rays were irradiated from a distance of 10 crIL for a total of 120 seconds on each of the front and back sides using a 3 kW high-pressure mercury lamp with a lamp output of 80 W/crIL. Thereafter, the mixture was heated and polymerized at 110° C. for 2 hours. The obtained high refractive index resin [3] was colorless and transparent. Various physical properties of this high refractive index resin as an optical material are also shown in Table 1.

Examples 4 to 7 High refractive index resin [
4] to [7] were obtained. Their physical properties as optical materials are also shown in Table 1.

Comparative Example 1 100 parts by weight of diethylene glycol bisallyl carbonate and 2.5 parts of diisopropyl peroxydicarbonate
The mixed solution with parts by weight was poured into a mold made of two glass plates and a silicone rubber gasket, and heated at 40°C for 1 hour, at 45°C for 1 hour, at 50°C for 1 hour, and at 60°C for 16 hours. Polymerization was carried out at 110°C for 2 hours and then at 110°C for 2 hours.

The obtained comparative resin [1] was colorless and transparent. Various physical properties of this comparative resin as an optical material are also shown in Table 1.

Comparative Example 2 Methyl methacrylate 100! A mixture of part i and 0.5 weight 1 L part of 2,2'-azobis-2,4-dimethylvaleronitrile was poured into a mold made of two glass plates and a silicone rubber gasket, and heated at 50°C. 6 hours, 6
Polymerization was carried out at 0°C for 16 hours and then at 90°C for 2 hours. The obtained comparative resin [2] was colorless and transparent. Various physical properties of this comparative resin [2] as an optical material are also shown in Table 1.

Comparative Examples 3 to 4 Comparative resins [3] to [4] were obtained in the same manner as in Example 1, except that the composition of the polymerizable monomer component in Example 1 was the same as shown in Table 1. Ta. Their physical properties as optical materials are also shown in Table 1.

Example 8 50 parts by weight of dipropylene glycol dimethacrylate, 40 parts by weight of styrene, 10 parts by weight of acrylonitrile, 2
,2'-azobis-2,4-dimethylvaleronitrile0
．． A mixture of 1 part by weight and 0.1 part by weight of 2-(2-hydroxy-5-methylphenyl)benzotriazole was poured into a mold consisting of two glass plates and a silicone rubber gasket, and the mixture was heated at 50°C for 6 hours. hold and then 110'
Polymerization was carried out by raising the temperature in C cabinet over 16 hours. The mixture was further held at 110° C. for 2 hours for post-polymerization. Obtained high refractive index resin [8]
was colorless and transparent. Table 2 shows the physical properties of this high refractive index resin as an optical material.

Examples 9 to 13 High refractive index resin [
9] to [13] were obtained. Their physical properties as optical materials are also shown in Table 2.

Example 14 50 parts by weight of trimethylolpropane trimethacrylate, 40 parts by weight of styrene, 10 parts by weight of acrylonitrile,
2. A mixture of 0.1 part by weight of 27-azobis-2,4-dimethylvaleronitrile and 0.1 part by weight of 2-(2-hydroxy-5-methylphenyl)benzotriazole was placed between two glass plates and silicone rubber. It was injected into a mold consisting of a gasket, held at 50°C for 6 hours, and then
The temperature was raised over 16 hours at C2 for polymerization. Further 110℃
The mixture was held for 2 hours and then polymerized. Obtained high refractive index resin [1
4] was colorless and transparent. Various physical properties of this high refractive index resin as an optical material are also shown in Table 2.

Examples 15 to 17 High refractive index resins [15] to [17] were obtained in the same manner as in Example 14, except that the composition of the raw material monomer was as shown in Table 2. . Their physical properties as optical materials are also shown in Table 2.

Example 18 30 parts by weight of tetraethylene glycol dimethacrylate, 1oti of trimethylolpropane trimethacrylate
t part, 50 parts by weight of styrene, 10 parts by weight of acrylonitrile, 0.1 part by weight of 2,2'-azobis-2,4-dimethylvaleronitrile, and 0.1 part by weight of 2-(2-hydroxy-5-methylphenyl)benzotriazole. Parts by weight of the mixture were poured into a mold consisting of two glass plates and a silicone rubber gasket, kept at 50°C for 6 hours, and then 1
Polymerization was carried out by raising the temperature at 10° C. over 16 hours. 110 more
The mixture was held at ℃ for 2 hours for post-polymerization. Obtained high refractive index resin [
18] was colorless and transparent. Table 3 shows the physical properties of this high refractive index resin as an optical material.

Examples 19 to 26 High refractive index resins [19] to [26] were obtained in the same manner as in Example 18, except that the composition of the raw material monomer was as shown in Table 3. . Table 3 also shows their physical properties as optical materials.

Example 27 1 part of tetraethylene glycol dimethacrylate 36, 1 part of 1,3-butanediol dimethacrylate 9f (:i
1 part by weight, 46 parts by weight of styrene, 9 parts by weight of acrylonitrile, 0.1 part by weight of 2-(2-hydroxy-5-methylphenyl)benzotriazole and 0 parts by weight of 4-methacryloyloxy-2,2,6,6-titramethylpiperidine. 0.1 part by weight of raw monomer and 0.1 part by weight of lauroyl peroxide.
2 parts by weight and 0.3 parts by weight of t-butylperoxy-2-ethylhexanoate were added, and the mixture was poured into a glass mold and a soft polyethylene mold designed to yield a lens with an inner diameter of 75 m and a power of -3,00 D. It was made with a gasket made of vinyl chloride and was gradually heated to 120'C1 over 15 hours, and then heated to 120'C1.
Cast polymerization was carried out by holding at 20°C for 30 minutes.

Next, the glass mold and gasket were removed from the polymerized product to obtain a lens [1] with a diameter of 75 ni and a power of -3.0 OD. The optical surface condition of the obtained lens [1] was good, and the various physical properties as a lens were excellent as shown in Table 4.

Examples 28 to 32 Lenses [2] to [6] were prepared in the same manner as in Example 27, except that the composition of the mixture consisting of the raw material monomer button and the polymerization initiator was changed as shown in Table 4. Obtained. The various physical properties of these lenses were excellent as shown in Table 4.

Comparative Examples 5 to 8 Lenses [7] to [10] were obtained in the same manner as in Example 27, except that the composition of the mixture consisting of the raw material monomer and the polymerization initiator was changed to the composition shown in Table 4. Ta. Table 4 shows the physical properties of those lenses.

The physical properties required for a lens were not satisfied.

In addition, the abbreviations in Tables 1 to 4 indicate the following compound names.

EG: Ethylene glycol dimethacrylate 2
EG: diethylene glycol dimethacrylate 3EG:) diethylene glycol dimethacrylate 4
EG: Tetraethylene glycol dimethacrylate 4KG': Tetraethylene glycol dimethacrylate 2PG: Dipropylene glycol dimethacrylate BG: 1,3-butanediol dimethacrylate BM: Butylene glycol dimethacrylate PM: Bentanediol dimethacrylate HM: Hexanediol dimethacrylate TMTM: ) Limethylolpropane trimethacrylate PETM: Pentaerythritol trimethacrylate 2PETM
: Dipentaerythritol trimethacrylate St
: Styrene α-8t : α-methylstyrene AN : Acrylonitrile MMA : Methyl methacrylate BzMA
: Benzyl methacrylate UMA : Polyurethane methacrylate (Kyo 4a Fat Chemical Industry ■
ADC: diethylene glycol diallyl carbonate V65: 2,2'-azobis(2,4-
dimethylvaleronitrile) V2O: 2,2'-azobisisobutyronitrile zpp: diisopropyl peroxydicarbonate BIE: benzoin isopropyl ether L, PO: lauroyl peroxide BEH: t-butyl peroxy-2-
Ethylhexanoate HMPBT: 2-(2hydroxy-5-methylphenyl)benzotriazole = 4-methacryloyl-2,2,6,6-titramethylpiperidine MP

Claims (1)

[Claims] 1. Polymerizable monomer [I] consisting of one or more polyfunctional (meth)acrylates represented by the following general formulas (1) to (2): 5 to 94.5 weight %, polymerizable monomer [II] consisting of styrene and/or α-methylstyrene 5~
94.5% by weight and a polymerizable monomer [III] consisting of 0.5 to 40% by weight of unsaturated nitrile (however, the total of the polymerizable monomer components is 100% by weight) An optical material made of a high refractive index resin with low specific gravity and excellent impact resistance obtained by radical polymerization of body components. (Note) General formula (1) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [In the formula, R_1 and R_2 are each independently H or OH_2, and X is ▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲
There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (However, R_3 is H, CH_2 or OH, l and m are 2 to 14 an integer, n is an integer from 4 to 14). ] General formula (2) ▲ Numerical formulas, chemical formulas, tables, etc. q represents an integer of 2 to 6.) 2. The polymerizable monomer component further contains a polymerizable monomer [I],
The optical material according to claim 1, which also contains another polymerizable monomer [IV] capable of radical copolymerization with [II] and/or [III]. 3. Polymerizable monomer [IV] is a group consisting of (meth)acrylic acid ester, (meth)allyl ester, allyl carbonate, allyl ether, epoxy (meth)acrylate, polyester (meth)acrylate, urethane (meth)acrylate The optical material according to claim 2, which is one or more polymerizable monomers selected from the following. 4. The optical material according to claim 3, wherein the polymerizable monomer [IV] is one or more selected from the group consisting of (meth)acrylic acid esters in an amount of 1 to 50% by weight. 5. A claim in which one or more selected from the group consisting of (meth)allyl ester, allyl carbonate, and allyl ether is used as the polymerizable monomer [IV] in an amount of 0.1 to 30% by weight. Optical material according to 3. 6. As the polymerizable monomer [IV], 1 selected from the group consisting of epoxy (meth)acrylate, polyester (meth)acrylate, and urethane (meth)acrylate
4. The optical material according to claim 3, wherein the species or two or more species are used in an amount of 1 to 50% by weight. 7. A lens made of the optical material according to claims 1 to 6.