JP2000136220A - Optical material made from synthetic resin and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an optical material made from a synthetic resin having a high refractive index, excellent in solvent resistance and mechanical characteristics, also having a high heat resistance and further having a large Abbe's number, and to provide a method for producing the same. SOLUTION: This optical material made from a synthetic resin consists of a copolymer obtained by treating the following components (A), (B) and (C) for polymerization. (A) Component: a fluorine derivative expressed by the formula [(m) and (n) are each 0-3 integer], (B) Component: a compound having isocyanate group and an unsaturated bond, (C) Component: an unsaturated compound copolymerizable with the component (B).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a synthetic resin optical material, and more particularly to a synthetic resin optical material having a high refractive index and excellent heat resistance and solvent resistance.

[0002]

2. Description of the Related Art Glass materials have conventionally been used as optical materials for forming lenses, prisms and the like, but recently, optical materials made of synthetic resins have been reduced in weight, workability and cost. It has been widely used with optical materials made of glass for reasons such as the possibility.

[0003] As synthetic resin optical materials, those made of a thermoplastic resin and those made of a thermosetting resin are known. However, since the optical material made of a thermoplastic resin has low heat resistance and solvent resistance, it is subjected to a heat history in post-processing such as formation of a hard coat layer for improving scratch resistance, or Contact with an organic solvent may cause deformation and surface deterioration. Further, an optical material made of a thermoplastic resin has a drawback that optical anisotropy such as birefringence easily occurs during molding. On the other hand, an optical material made of a thermosetting resin having a crosslinked structure has higher heat resistance and solvent resistance than an optical material made of a thermoplastic resin. It has the potential as an alternative material. Therefore, optical materials made of various thermosetting resins have been conventionally proposed. For example, JP-A-63-
JP 2001-163702, JP 2-58511, and the like disclose a synthetic resin optical material comprising a crosslinked copolymer having a urethane bond.

However, these synthetic resin optical materials are mainly used for spectacle lenses, and can withstand the heat history in post-processing but do not have higher heat resistance. In some cases, they are not sufficient as a substitute for glass optical materials. Further, from the viewpoint of reducing the thickness and weight of the lens, it is preferable that the optical material has a high refractive index. Further, it is preferable that the optical material has low light dispersion, that is, a material having a large Abbe number. for that reason,
It has been strongly desired to develop a synthetic resin optical material having a high refractive index, excellent solvent resistance, excellent mechanical properties, high heat resistance, and a large Abbe number.

[0005]

SUMMARY OF THE INVENTION The present invention has been made based on the above circumstances. A first object of the present invention is to have a high refractive index, excellent solvent resistance, excellent mechanical properties,
Moreover, it is to provide a synthetic resin optical material having high heat resistance. A second object of the present invention is to provide a synthetic resin optical material having a high refractive index, excellent solvent resistance, excellent mechanical properties, high heat resistance, and a large Abbe number. A third object of the present invention is to provide a method capable of advantageously producing the above-mentioned synthetic resin optical material.

[0006]

The synthetic resin optical material of the present invention comprises a copolymer obtained by polymerizing the following components (A), (B) and (C). It is characterized by. (A) component: a fluorene derivative represented by the following formula (1), (B) component: a compound having an isocyanate group and an unsaturated bond, (C) component: an unsaturated compound copolymerizable with the (B) component.

[0007]

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[0008] The synthetic resin optical material of the present invention comprises a copolymer obtained by polymerizing the following components (A), (B), (C) and (D). It is characterized by becoming. (A) component: a fluorene derivative represented by the above formula (1), (B) component: a compound having an isocyanate group and an unsaturated bond, (C) component: an unsaturated compound copolymerizable with the (B) component. , (D) component: a compound having two or more mercapto groups in the molecule

The synthetic resin optical material of the present invention further comprises a urethane bond-containing monomer obtained by subjecting the component (A) and the component (B) to a urethane reaction, the component (C), (D) It is characterized by comprising a copolymer obtained by polymerizing the component.

In the synthetic resin optical material of the present invention,
When the number of moles of hydroxyl groups in the component (A) is a and the number of moles of isocyanate groups in the component (B) is b ₁ , the ratio (a / b ₁ ) is 0.95 to 1.2. Preferably, there is. Further, the total ratio of the component (A) and the component (B) is preferably 5 to 60% by mass of the total of all components to be polymerized. Further, the number of moles of unsaturated bonds in the component (B) is b ₂ ,
The mole number of the unsaturated bond in the component (C) is represented by c,
When the number of moles of the mercapto group in the component (D) is d, the value of the ratio [(b ₂ + c) / d] is preferably 1.9 or more.

The method for producing an optical material made of synthetic resin according to the present invention is characterized in that the component (A) and the component (B) are subjected to a urethanization reaction in the presence of the component (C) to obtain a urethane bond-containing monomer. Preparing a copolymer, and thereafter, polymerizing the urethane bond-containing monomer with the component (C) to obtain a copolymer. Also,
The method for producing a synthetic resin optical material according to the present invention includes the method (C)
A urethane bond-containing monomer is prepared by subjecting the component (A) and the component (B) to a urethane reaction in the presence of the component, and thereafter, the urethane bond-containing monomer and the component (C) And a step of obtaining a copolymer by polymerizing the component (D).

[0012]

Embodiments of the present invention will be described below in detail. The synthetic resin optical material of the present invention comprises the fluorene derivative represented by the above formula (1) (A)
Crosslinking obtained by polymerizing a component, a component (B) composed of a compound having an isocyanate group and an unsaturated bond, and a component (C) composed of an unsaturated compound copolymerizable with the component (B). By subjecting the copolymer or the component (A), the component (B), the component (C), and the component (D) comprising a compound having two or more mercapto groups in a molecule to a polymerization treatment. The resulting crosslinked copolymer (hereinafter, these crosslinked copolymers are also referred to as “specific crosslinked copolymers”).

<Component (A)> The fluorene derivative represented by the above formula (1) used as the component (A) (hereinafter referred to as “component (A)”)
Also referred to as “specific fluorene derivative”. ) Has two hydroxyl groups capable of urethanation reaction with an isocyanate group in the molecule. As shown in the formula (1), the specific fluorene derivative contains a high proportion of an aromatic ring in the molecule. By using such a specific fluorene derivative as the component (A), the refractive index can be increased. Is obtained.

In the formula (1) showing the structure of a specific fluorene derivative, the values of m and n are integers of 0 to 3, preferably 1 to 2. When the value of m or n exceeds 3, the proportion of the aromatic ring in the molecule of the fluorene derivative becomes relatively low, so that a crosslinked copolymer having a high refractive index and a small specific gravity cannot be obtained. When the values of m and n are 0, the reactivity with the isocyanate group in the component (B) is reduced due to steric hindrance. As a result, a large amount of unreacted hydroxyl groups and isocyanate groups remain. In some cases, yellowing or devitrification may occur in the obtained crosslinked copolymer. As such a specific fluorene derivative,
9,9-bis (4- (2-hydroxyethoxy) phenyl) fluorene can be preferably used.

<Component (B)> The component (B) is a compound having both one isocyanate group and one unsaturated double bond in the molecule. The isocyanate group in this component (B) undergoes a urethanization reaction with the hydroxyl group in the above-mentioned component (A) to form a urethane bond, and the resulting copolymer has a cross-linked structure formed by residues derived from the component (A). It is formed. On the other hand, the unsaturated double bond in the component (B) undergoes an addition polymerization reaction with the unsaturated double bond in the component (C) to be described later, or the unsaturated double bond in the component (D) to be described later. A copolymer is formed by a radical polyaddition reaction with a mercapto group. As such a component (B), m-isopropenyl-α, α-dimethylbenzyl isocyanate can be preferably used.

<Component (C)> The component (C) is composed of an unsaturated compound copolymerizable with the component (B) (hereinafter, also referred to as “copolymerizable monomer”). Such a copolymerizable monomer includes a monofunctional unsaturated compound having one unsaturated double bond in the molecule and an unsaturated double bond having two unsaturated double bonds in the molecule.
Any of the polyfunctional unsaturated compounds having at least one aromatic compound such as styrene, α-methylstyrene, divinylbenzene, p-tert-butylstyrene, and m-diisopropenylbenzene can be used. '-
Bis (methacryloylthio) diphenyl sulfide,
Sulfur-containing compounds such as 1,2-bis (methacryloylthio) ethane, 2,2-bis (4- (meth) acryloyloxyethyldiphenyl) propane, 2,2-bis (3
Bisphenol A derivatives such as 5-dibromo-4-methacryloyloxyethyldiphenyl) propane and the like can be suitably used in that an optical material having a high refractive index can be obtained. Further, a fluorene derivative such as bisphenoxyethanol fluorene (meth) acrylate can also be used.

In the present invention, the copolymerizable monomer used as the component (C) is not limited to the above compounds. Further, these compounds are appropriately selected according to the properties required for the target optical material, and are used as the component (C) alone or in combination of two or more. For example, when higher heat resistance is required for the target optical material, it is preferable to use a polyfunctional unsaturated compound as the component (C).

<Component (D)> The component (D) is a compound having two or more mercapto groups in a molecule (hereinafter, referred to as a "polythiol compound"). Accordingly, specifically, the component (D) is an optional component used when a target optical material is required to have low light dispersibility, that is, a material having a large Abbe number. Is copolymerized by a radical polyaddition reaction with the reaction product of the aforementioned components (A) and (B) or the polyfunctional unsaturated compound in the component (C).

Specific examples of such a polythiol compound include 1,4-bismercaptomethylbenzene, ethanedithiol, 1,4-butanedithiol, ethylene glycol dithioglycolate, 1,2-propanedithiol, and bismercaptoethyl sulfide. , Bis (mercaptoethylthio) ethane, trimethylolpropane tris (thioglycolate), trimethylolpropane tris (thiopropionate), pentaerythritol tetrakis (thioglycolate), pentaerythritol tetrakis (thiopropionate), etc. Examples include, but are not limited to, these compounds. In addition, these compounds can be used alone or in combination of two or more as the component (D).

<Specific Cross-Linked Copolymer> The specific cross-linked copolymer constituting the synthetic resin optical material of the present invention may be any one of the above components (A), (B) and (C), or And a component (D) obtained by polymerization. Specifically, the hydroxyl group in the component (A) and the isocyanate group in the component (B) undergo a urethanization reaction, and the unsaturated double bond in the component (B) and the unsaturated double bond in the component (C) are combined. A specific crosslinked copolymer can be obtained by addition polymerization and further by subjecting these unsaturated double bonds to a polyaddition reaction with the mercapto group in the component (D).

The ratio of the component (A) to the component (B) is
(A) the number of moles of hydroxy groups in component and a, (B) when the number of moles of the isocyanate groups of component a b _1, the value of the ratio (a / b ₁₎ is 0.95 to 1.2 Is preferred. When the value of this ratio (a / b ₁ ) is less than 0.95, unreacted isocyanate groups remain in a high concentration, and thus the isocyanate groups constitute a mold in casting polymerization described below. As a result of reacting with the glass surface, the releasability of the obtained molded article of the crosslinked copolymer may be remarkably reduced, or the weather resistance and the temporal stability of the obtained crosslinked copolymer may be reduced. On the other hand, this ratio (a
When the value of / b ₁ ) exceeds 1.2, a high ratio of hydroxyl groups remains in the obtained cross-linked copolymer, so that the weather resistance and the temporal stability of the cross-linked copolymer are reduced, or The crosslinked copolymer may have high water absorption, and furthermore, when the obtained optical material is subjected to processing such as an antireflection film by an inorganic vapor deposition film, a cause of impairing the durability of the inorganic vapor deposition film. It may be.

The total proportion of the components (A) and (B) is preferably 5 to 60% by mass of the total of all the components to be polymerized. If this proportion is less than 5% by mass, the structural units derived from the component (A) will be too small, so that a crosslinked copolymer having a high refractive index may not be obtained. Further, as a result of an excessively high proportion of the component (C),
When styrene, divinylbenzene, or the like is used as the component (C), the resulting radically polymerizable monomer composition has high solubility in the sealing material of the mold used in the casting polymerization described below, so that moldability is high. May be significantly reduced. On the other hand, when this ratio exceeds 60% by mass, the obtained crosslinked copolymer may have a large specific gravity. In addition, as a result of the proportion of the component (C) being too small, the resulting radically polymerizable monomer composition may have a high viscosity, which may make casting polymerization difficult.

When the component (D) is used,
The number of moles of unsaturated bonds in the component (B) is b ₂ ,
The mole number of the unsaturated bond in the component (C) is represented by c,
When the number of moles of the mercapto group in the component (D) is d, the ratio of the sum of the unsaturated bonds in the component (B) and the unsaturated bonds in the component (C) to the mercapto group [(b ₂
+ C) / d] is preferably 1.9 or more.
If the value of the ratio [(b ₂ + c) / d] is less than 1.9, the resulting crosslinked copolymer may have low heat resistance.

In the present invention, a mixture comprising the above-mentioned components (A), (B) and (C) or a mixture comprising these components and (D) is added to a urethane reaction catalyst and a radical polymerization initiator. Is added, and the urethanization reaction and the radical polymerization reaction are allowed to proceed simultaneously under appropriate conditions, whereby a specific crosslinked copolymer can be obtained. However, when casting polymerization described below is performed, urethane is formed in that the elution of the sealing material constituting the glass mold is small, the polymerization shrinkage is small, and the releasability from the glass mold is good. A urethane bond-containing monomer is prepared by subjecting the components (A) and (B) to urethanization reaction in the presence of a reaction catalyst, and then the urethane bond-containing monomer is prepared in the presence of a radical polymerization initiator. It is preferable to produce a specific crosslinked copolymer by subjecting the monomer and the component (C) or the component and the component (D) to a radical polymerization reaction.

In the above method, since the obtained urethane bond-containing monomer is a considerably viscous liquid or solid, it is difficult to sufficiently dissolve the urethane bond-containing monomer in the component (C). It may be. Therefore, when preparing the urethane bond-containing monomer, the component (C) is used as a solvent for the urethanization reaction between the component (A) and the component (B), that is, in the presence of the component (C), A)
It is preferable that the component and the component (B) undergo a urethanization reaction. Specifically, the components (A), (B) and (C)
A urethanization reaction catalyst is added to the mixture of the components, and the components (A) and (B) in the mixture are urethanized under appropriate conditions. As a result, a monomer mixture in which the urethane bond-containing monomer as a reaction product is dissolved in the component (C) is obtained.

In such a method, when performing the urethanization reaction between the component (A) and the component (B), all of the component (C) used to obtain a specific crosslinked copolymer is used. It is also possible to prepare a monomer mixture by performing a urethanization reaction between the component (A) and the component (B) using a part of the component (C) to be used, and thereafter, the obtained reaction product liquid And the remaining component (C) may be added to the mixture to prepare a monomer mixture.

As the urethanization catalyst for the urethanization reaction between the components (A) and (B), amine catalysts, metal salt catalysts, organometallic catalysts and the like can be used. , Dibutyltin acetate,
A highly active organotin catalyst such as dibutyltin dilaurate is preferred. The urethanization reaction between the component (A) and the component (B) can be carried out at the same temperature and for the same time as the usual urethanization reaction, but the components (B) and (C) are unsaturated double Since it has a bond, it is preferable to perform the reaction under relatively mild conditions. From such a viewpoint, it is preferable to use a highly active urethane-forming catalyst.

By adding a radical polymerization initiator to the monomer mixture obtained as described above or further to the monomer mixture obtained by mixing the component (D), the radical polymerizable monomer composition is obtained. Can be prepared. As the radical polymerization initiator, an ordinary organic peroxide-based polymerization initiator is used, but tert-butyl peroxy neodecanoate,
tert-butyl peroxypivalate, tert-butyl peroxy-2-ethylhexanoate, tert
Non-aromatic peroxyesters such as -butylperoxylaurate, lauroyl peroxide, 3,5,5
-A diacyl peroxide such as trimethylhexanoyl peroxide can be preferably used. Also, 2,2′-azobis (isobutyronitrile) and 2,2′-azobis (isobutyronitrile)
2'-azovisi (2,4-dimethylvaleronitrile),
An azo radical polymerization initiator such as 1,1'-azobis (cyclohexane-2-carbonitrile) can also be preferably used. In addition, additives such as an antioxidant, an ultraviolet absorber, a polymerization rate regulator, and a light stabilizer can be added to the radical polymerizable monomer composition as needed.

By subjecting such a radical polymerizable monomer composition to a polymerization treatment, a specific crosslinked copolymer constituting the synthetic resin optical material of the present invention can be obtained. The specific polymerization treatment method is not particularly limited, and a usual polymerization method can be adopted, but the specific cross-linked copolymer obtained is difficult to use as a molding material in a molding method involving melting. Therefore, it is preferable to use a casting polymerization method in which a shape as a target optical product is directly obtained. In addition, it is possible to obtain an optical product having a required shape by producing a molded product having a size larger than the intended optical product by a cast polymerization method and subjecting the molded product to a cutting process.

When a specific cross-linked copolymer is obtained by a casting polymerization method, for example, a pair of glass mold plates is provided.
A mold composed of a gasket or a sealing material such as an adhesive tape is used. Specifically,
By disposing a pair of mold plates at a constant interval so as to face each other, and surrounding the side surfaces of these mold plates with a sealing material, a mold having a cavity formed between the pair of mold plates is configured. . Then, the radical polymerizable monomer composition is injected into the cavity of the mold and heated or irradiated with light so that the urethane bond-containing monomer in the radical polymerizable monomer composition and ( The component (C) or the component (D) is copolymerized with the component (C), whereby a specific crosslinked copolymer molded into, for example, a sheet, a plate, or another shape is obtained.

In the above, when a component acting as an organic solvent such as styrene is used as the component (C), a material made of a solvent-resistant material, for example, a gasket made of a fluorine-based rubber or the like is used as a sealing material. However, since the urethane bond-containing monomer is dissolved in the component (C), the erosion of the component (C) is reduced, so that the sealing material is not necessarily high in solvent resistance. It is not necessary to use a material such as an ethylene-vinyl acetate copolymer or an ethylene-ethyl acrylate copolymer, which is commonly used for casting polymerization of spectacle lenses. In addition, the radical polymerization reaction in the cavity of the mold can be performed at the same reaction temperature and reaction time as in a normal radical polymerization reaction.

[0032]

EXAMPLES The present invention will be described below in more detail with reference to Examples, but it should not be construed that the invention is limited thereto.
In the following, “parts” means “parts by mass”.

Example 1 18.78 parts of 9,9-bis (4- (2-hydroxyethoxy) phenyl) fluorene, 16.22 parts of m-isopropenyl-α, α-dimethylbenzyl isocyanate, and To a mixture with 45 parts of pure divinylbenzene (purity: 96% by mass), 0.05 parts of di-n-butyltin dilaurate as a urethanation catalyst was added, and the mixture was treated with 9,9-bis ( 4-
(2-hydroxyethoxy) phenyl) fluorene;
Urethane reaction was performed with m-isopropenyl-α, α-dimethylbenzyl isocyanate. Thereafter, bismercaptoethyl sulfide was added to the obtained reaction product solution.
0 parts and 0.2 parts of 2- (2'-hydroxy-5'-tert-octylphenyl) benztriazole as an ultraviolet absorber were added, and these were stirred and dissolved. By adding 0.8 parts of tert-butylperoxy-2-ethylhexanoate as a polymerization initiator to the monomer mixture thus prepared, a radically polymerizable monomer composition was obtained. In the above, the value of the ratio (a / b ₁ ) of the molar number a of the hydroxyl group in the component (A) to the molar number b ₁ of the isocyanate group in the component (B) is 1.06, and the component (A) And the ratio of the total of the components (B) is
35.6% by mass of the total of the components (A) to (D), the sum of the number of moles b _{2 of} unsaturated bonds in the component (B) and the number c of moles of unsaturated bonds in the component (C),
The value of the ratio [(b ₂ + c) / d] to the number of moles d of the mercapto group in the component (D) is 2.97.

This radical polymerizable monomer composition was molded into a circular glass mold plate 2 having a thickness of 5 mm and a diameter of 80 mm.
Into a glass mold composed of a sheet and a silicone rubber gasket having a thickness of 1 mm and a width of 5 mm.
After holding at 5 ° C. for 8 hours, the temperature was raised to 65 ° C. over 4 hours, then raised to 120 ° C. over 2 hours, and further increased to 120 ° C.
By holding at 1 ° C. for 1 hour, cast polymerization of the monomer was carried out. Then, the temperature of the glass mold is lowered to 60 ° C.
4.7mm thick by releasing from mold plate
A colorless and transparent disc-shaped optical material was obtained.

This optical material has a refractive index at 20 ° C. (according to ASTM D542) of 1.630 and a specific gravity (AS
TMD792) was 1.17, and the Abbe number was 30. Further, when the penetration at 100 ° C. was measured under a load of 5 kg by a Vicat softening point measurement method based on ASTM D1525, the penetration was 0.1 mm, and it was confirmed that the material had high heat resistance. In addition, when immersed in each of methanol, toluene and acetone at room temperature for 24 hours, no surface abnormality such as cracking was observed, and it was confirmed that the material was excellent in solvent resistance.

Example 2 13.04 parts of 9,9-bis (4- (2-hydroxyethoxy) phenyl) fluorene and 11.96 parts of m-isopropenyl-α, α-dimethylbenzyl isocyanate were added. A mixture with 25.0 parts of pure divinylbenzene (purity: 96% by mass) was mixed with 0.05% of di-n-butyltin dilaurate as a urethanation catalyst.
And 9,9-bis (4- (2-hydroxyethoxy) phenyl) fluorene is reacted with m-isopropenyl-α, α-dimethylbenzyl isocyanate at 50 ° C. for 3 hours. I let it. Thereafter, 30.0 parts of pentaerythritol tetrakis (thiopropionate) and 2,2-bis (4
-(Meth) acryloyloxyethyldiphenyl) propane (20.0 parts) and 2- (2 ′
-Hydroxy-5'-tert-octylphenyl) benztriazole 0.2 part was added and these were stirred to dissolve. A radically polymerizable monomer composition was obtained by adding 1.0 part of tert-butyl peroxypivalate as a polymerization initiator to the monomer mixture thus prepared. In the above, the value of the ratio (a / b ₁ ) of the molar number a of the hydroxyl group in the component (A) to the molar number b ₁ of the isocyanate group in the component (B) is 1.0, and the component (A) And the ratio of the total of the components (B) is
25.3% by mass of the total of the components (A) to (D), and the sum of the number of moles b _{2 of} unsaturated bonds in the component (B) and the number c of moles of unsaturated bonds in the component (C);
The value of the ratio [(b ₂ + c) / d] to the number of moles d of the mercapto group in the component (D) is 2.14.

This radical polymerizable monomer composition was prepared with a thickness of 5
into a glass mold composed of two circular glass mold plates having a diameter of 80 mm and a diameter of 80 mm, and an adhesive tape coated with a silicone adhesive.
After holding for 4 hours, the temperature was raised to 65 ° C. over 4 hours, then to 100 ° C. over 2 hours, and further maintained at 100 ° C. for 1 hour to perform cast polymerization of the monomer. Thereafter, the temperature of the glass mold was lowered to 60 ° C., and the mold was released from the mold plate, whereby a colorless and transparent disk-shaped optical material having a thickness of 4.7 mm was obtained.

This optical material has a refractive index at 20 ° C. (according to ASTM D542) of 1.597 and a specific gravity (AS
TMD792) was 1.17, and the Abbe number was 32. Further, when the penetration at 100 ° C. under a load of 5 kg was measured by a Vicat softening point measurement method based on ASTM D1525, it was 0.3 mm, and it was confirmed that the material had high heat resistance. In addition, when immersed in each of methanol, toluene and acetone at room temperature for 24 hours, no surface abnormality such as cracking was observed, and it was confirmed that the material was excellent in solvent resistance.

Example 3 13.90 parts of 9,9-bis (4- (2-hydroxyethoxy) phenyl) fluorene and 12.77 parts of m-isopropenyl-α, α-dimethylbenzyl isocyanate were added. A mixture with 26.67 parts of pure divinylbenzene (purity: 96% by mass) was added with di-n-butyltin dilaurate as a urethanation catalyst in an amount of 0.06%.
5 parts were added and 9,9-bis (4- (2-hydroxyethoxy) phenyl) fluorene and m-isopropenyl-α, α-dimethylbenzyl isocyanate were urethanized at 50 ° C. for 3 hours. Reacted. Thereafter, 30.0 parts of 4,4′-bis (methacryloylthio) diphenyl sulfide, 16.67 parts of bismercaptoethyl sulfide, and 2- (2′-hydroxy-5′-) as an ultraviolet absorber were added to the obtained reaction product liquid. 0.5 part of tert-octylphenyl) benztriazole and 0.1 part of bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate as a light stabilizer were added, and these were stirred and dissolved. . A radically polymerizable monomer composition is obtained by adding 0.6 parts of 1,1′-azobis (cyclohexane-2-carbonitrile) as a polymerization initiator to the monomer mixture thus prepared. Was. In the above, the ratio (a / molar) of the molar number a of the hydroxyl group in the component (A) to the molar number b ₁ of the isocyanate group in the component (B).
The value of b ₁ ) is 1.0, and the components (A) and (B)
The total ratio of the components is 27.0% by mass of the total of the components (A) to (D), the number of moles b _{2 of the} unsaturated bonds in the component (B) and the number of the unsaturated bonds in the component (C). The value of the ratio [(b ₂ + c) / d] of the total of the number of moles c to the number of moles d of the mercapto group in the component (D) is 2.91.

This radical polymerizable monomer mixed solution was placed in a glass mold composed of two circular glass mold plates having a thickness of 5 mm and a diameter of 80 mm and an adhesive tape coated with an acrylic adhesive. At 45 ° C.
After maintaining for 5 hours, the temperature was raised to 65 ° C. over 4 hours, then to 120 ° C. over 2 hours, and further maintained at 120 ° C. for 3 hours to perform cast polymerization of the monomer. . Thereafter, the temperature of the glass mold was lowered to 70 ° C., and the mold was released from the mold plate to obtain a colorless and transparent disk-shaped optical material having a thickness of 4.5 mm.

This optical material has a refractive index at 20 ° C. (according to ASTM D542) of 1.647 and a specific gravity (AS
TMD792) was 1.21, and the Abbe number was 26. Further, when the penetration at 100 ° C. was measured under a load of 5 kg by a Vicat softening point measurement method based on ASTM D1525, the penetration was 0.1 mm, and it was confirmed that the material had high heat resistance. In addition, when immersed in each of methanol, toluene and acetone at room temperature for 24 hours, no surface abnormality such as cracking was observed, and it was confirmed that the material was excellent in solvent resistance.

Example 4 17.2 parts of 9,9-bis (4- (2-hydroxyethoxy) phenyl) fluorene and 15.8 parts of m-isopropenyl-α, α-dimethylbenzyl isocyanate were used. A mixture with 15.0 parts of pure divinylbenzene (purity: 81% by mass) was added with 0.05% of di-n-butyltin dilaurate as a urethanization catalyst.
And 9,9-bis (4- (2-hydroxyethoxy) phenyl) fluorene is reacted with m-isopropenyl-α, α-dimethylbenzyl isocyanate at 50 ° C. for 3 hours. I let it. Thereafter, 42.0 parts of phenoxyethyl methacrylate, 10 parts of styrene, and 0.5 part of 2- (2'-hydroxy-5'-tert-octylphenyl) benztriazole as an ultraviolet absorber were added to the obtained reaction product liquid. Were added and these were stirred to dissolve. A radically polymerizable monomer composition was obtained by adding 0.8 parts of tert-butyl peroxyneodecanate as a polymerization initiator to the monomer mixture thus prepared. In the above, (A)
The value of the ratio (a / b ₁ ) of the molar number a of the hydroxyl group in the component to the molar number b ₁ of the isocyanate group in the component (B) is 1.0, and the ratio of the component (A) and the component (B) is The total ratio is 34.0% by mass of the total of the components (A) to (C). In this example, since the component (D) was not used, the number of moles d of the mercapto group was 0.

This radical polymerizable monomer mixed solution was placed in a glass mold composed of two circular glass mold plates each having a thickness of 3 mm and a diameter of 80 mm, and an adhesive tape coated with an acrylic adhesive. And 8 at 40 ° C
After maintaining the temperature for 4 hours, the temperature was raised to 70 ° C. over 4 hours, then raised to 100 ° C. over 2 hours, and further maintained at 100 ° C. for 3 hours to perform cast polymerization of the monomer. Thereafter, the temperature of the glass mold was lowered to 70 ° C., and the mold was released from the mold plate, thereby obtaining a colorless and transparent disc-shaped optical material having a thickness of 2.7 mm.

This optical material has a refractive index at 20 ° C. (according to ASTM D542) of 1.594 and a specific gravity (AS
TMD792) 1.15 and Abbe number 31. Further, when the penetration at 100 ° C. under a load of 5 kg was measured by a Vicat softening point measurement method based on ASTM D1525, it was 0.45 mm, and it was confirmed that the material had high heat resistance. In addition, when immersed in each of methanol, toluene and acetone at room temperature for 24 hours, no surface abnormality such as cracking was observed, and it was confirmed that the material was excellent in solvent resistance.

[0045]

As described above, according to the present invention,
It is possible to provide a synthetic resin optical material having a high refractive index, excellent solvent resistance, high heat resistance, and a large Abbe number. Such a synthetic resin optical material is suitable as a substitute material for a glass optical material, and can be applied to, for example, a lens, a prism, a mirror base material, and various window materials. According to the production method of the present invention, the above-mentioned synthetic resin optical material can be advantageously produced.

Continued on the front page F-term (reference) 4J027 AC03 AC08 AJ02 BA03 BA05 BA07 BA18 BA19 CA26 CB03 CC02 CD03 CD04 4J100 AB02Q AB03Q AB07P AB15P AB15Q AB16Q AL62Q AL66Q BA02P BA08P BA38P BA51Q BB03Q BC43P BC43CA40 JA33

Claims (8)

[Claims] 1. An optical material made of a synthetic resin, comprising a copolymer obtained by polymerizing the following component (A), the following component (B), and the following component (C). Component (A): a fluorene derivative represented by the following formula (1): Component (B): a compound having an isocyanate group and an unsaturated bond. Component (C): an unsaturated compound copolymerizable with the component (B). 1) 2. A synthetic resin optical material comprising a copolymer obtained by subjecting the following component (A), the following component (B), the following component (C), and the following component (D) to a polymerization treatment. material. Component (A): a fluorene derivative represented by the formula (1) according to claim 1 Component (B): a compound having an isocyanate group and an unsaturated bond Component (C): copolymerizable with the component (B) Unsaturated compound (D) component: a compound having two or more mercapto groups in the molecule 3. A polymer obtained by polymerizing a urethane bond-containing monomer obtained by subjecting the following component (A) and the following component (B) to a urethane reaction, the following component (C), and the following component (D): An optical material made of a synthetic resin, comprising the obtained copolymer. Component (A): a fluorene derivative represented by the formula (1) according to claim 1 Component (B): a compound having an isocyanate group and an unsaturated bond Component (C): radical copolymerizable with the component (B) Unsaturated Compound (D) Component: Compound Having Two or More Mercapto Groups in the Molecule 4. The mole number of a hydroxyl group in the component (A) is represented by a
And then, (B) when the number of moles of the isocyanate groups of component a b _1, the value of the ratio (a / b ₁₎ is 0.95.
The synthetic resin optical material according to any one of claims 1 to 3, wherein 5. The method according to claim 1, wherein the total proportion of the component (A) and the component (B) is 5 to 60% by mass of the total of all the components to be polymerized. An optical material made of the synthetic resin according to any one of the above items 6. The number of moles of unsaturated bonds in component (B) is b ₂ , the number of moles of unsaturated bonds in component (C) is c, and the number of moles of mercapto group in component (D) is d.
4. The synthetic resin optical material according to claim 2, wherein the value of the ratio [(b ₂ + c) / d] is 1.9 or more. 7. In the presence of the following component (C), the following (A)
A urethane bond-containing monomer is prepared by subjecting the component and the following component (B) to a urethanization reaction, and then the copolymer is obtained by polymerizing the urethane bond-containing monomer and the following component (C). A method for producing a synthetic resin optical material, comprising the step of: Component (A): a fluorene derivative represented by the formula (1) according to claim 1 Component (B): a compound having an isocyanate group and an unsaturated bond Component (C): radical copolymerizable with the component (B) Unsaturated compounds 8. In the presence of the following component (C), the following (A)
A urethane bond-containing monomer is prepared by subjecting the component and the following component (B) to urethanization reaction, and thereafter, the urethane bond-containing monomer is polymerized with the following component (C) and the following component (D). A process for obtaining a copolymer by the method. Component (A): a fluorene derivative represented by the formula (1) according to claim 1 Component (B): a compound having an isocyanate group and an unsaturated bond Component (C): radical copolymerizable with the component (B) Unsaturated Compound (D) Component: Compound Having Two or More Mercapto Groups in the Molecule