Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Mixing of two or more solid polymers; mixing of solid...
Reexamination Certificate
2001-01-23
2002-07-09
Sergent, Rabon (Department: 1711)
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
Mixing of two or more solid polymers; mixing of solid...
C522S142000, C522S143000, C522S144000, C522S090000, C522S095000, C522S096000, C522S173000, C522S174000, C522S180000, C522S181000, C522S182000, C522S183000, C525S127000, C525S455000, C525S457000, C526S286000, C526S288000, C526S301000, C351S159000, C359S642000
Reexamination Certificate
active
06417273
ABSTRACT:
TECHNICAL FIELD
The present invention relates to a monomer composition which provides a plastic optical material having high refractive index and Abbe number, a low specific gravity and excellent physical properties, such as dyeing properties, heat resistance, impact resistance and the like, a plastic optical material and a lens.
BACKGROUND ART
In recent years, in the field of optical materials used for lenses and the like, the properties for reduced weight, safety, fashion and the like are being regarded as great importance, and the material is changing from the conventional inorganic glass to synthetic resins. As representative synthetic resin materials, polydiethylene glycol bisallyl carbonate (hereinafter, referred to simply as “PADC”), polymethyl methacrylate (hereinafter, referred to simply as “PMMA”), polycarbonate (hereinafter, referred to simply as “PC”), and the like are well known.
PADC and PMMA are more excellent than inorganic glass in respect of the low specific gravity, the impact resistance and the dyeing properties. However, the refractive index of each of PADC and PMMA is about 1.49, and the refractive index is lower than that of the general inorganic glass which is 1.52. Therefore, there has been a drawback in that, when the lens becomes stronger, the thickness of the lens becomes larger. In addition, in PC, the refractive index is as high as about 1.58, but the Abbe number is as low as 29. Further, PC is shaped by a melt molding method, and thus, PC had other problems about optical anisotropy, discoloration and the like.
For solving these problems, a plastic lens having a higher refractive index and a higher Abbe number is disclosed. For example, in Japanese Unexamined Patent Publication No. Sho 55-13747, a copolymer of dimethacrylate of a bisphenol A derivative and styrene is disclosed. In Japanese Unexamined Patent Publication No. Sho 55-69543, a polymer of dimethacrylate of a halogenated bisphenol A derivative is disclosed.
In Japanese Unexamined Patent Publication No. Sho 63-23908, for the purpose of further increasing the refractive index, a polymer of diallyl diphenate is disclosed. In Japanese Patent No. 2707613, a polymer comprising an isocyanate compound having an unsaturated group and polythiol is disclosed. In Japanese Unexamined Patent Publication No. Sho 62-267316, a thiourethane resin comprising polyisocyanate and polythiol is disclosed.
However, with respect to the copolymer disclosed in Japanese Unexamined Patent Publication No. Sho 55-13747, the refractive index is about 1.55 and was not satisfactory. With respect to the polymer disclosed in Japanese Unexamined Patent Publication No. Sho 55-69543, the refractive index is as high as about 1.60; however, the specific gravity was high due to halogenation, and the weathering resistance was poor.
Further, with respect to the polymer disclosed in Japanese Unexamined Patent Publication No. Sho 63-23908, the Abbe number was as low as about 29, and the impact resistance was poor. With respect to the polymer in Japanese Patent No. 2707613, the refractive index is about 1.58 and was not satisfactory, and the heat resistance also was poor. The resin disclosed in Japanese Unexamined Patent Publication No. Sho 62-267316 had a high specific gravity and a poor heat resistance.
DISCLOSURE OF THE INVENTION
It is an object of the present invention to provide a monomer composition for a plastic optical material, a plastic optical material and a lens, which are excellent in respect of refractive index, Abbe number, specific gravity, heat resistance, dyeing properties and impact resistance.
For attaining the above object, the first embodiment of the present invention provides a monomer composition for a plastic optical material, which comprises: a di(meth)acrylate compound; at least one of divinylbenzene and divinylbiphenyl; a crosslinking-type isocyanate compound; a compound having two or more thiol groups; and a thiourethane bonding accelerating compound.
The second embodiment of the present invention provides a monomer composition for a plastic optical material, which comprises: a di(meth)acrylate compound; at least one of divinylbenzene and divinylbiphenyl; and a reaction product of a crosslinking-type isocyanate compound with a compound having two or more thiol groups.
The di(meth)acrylate is preferably represented by the following chemical formula (1):
wherein R
1
represents a hydrogen atom or a methyl group, Ph represents a phenylene group, x and z may be the same or different and each represent an integer of 1 to 5, and y is 0 or 1.
The thiourethane bonding accelerating compound is preferably at least one compound selected from the group consisting of an amine compound, an amine salt compound and an organometallic compound.
The third embodiment of the present invention provides a plastic optical material obtained by curing a mixture of the above-mentioned monomer composition and a radical polymerization initiator.
The fourth embodiment of the present invention provides a lens produced from the above-mentioned plastic optical material.
The above lens preferably has a hard coat layer on a surface thereof.
BEST MODE FOR CARRYING OUT THE INVENTION
The monomer composition for a plastic optical material of the present embodiment comprises, as essential components, the following components: a di(meth)acrylate compound, divinylbenzene and/or divinylbiphenyl (hereinafter, referred to as “divinylphenyl compound”), a crosslinking-type isocyanate compound, and a compound having two or more thiol groups (hereinafter, referred to as “polythiol compound”). And, a thiourethane bonding accelerating compound can be further added.
The di(meth)acrylate compound means a compound having two (meth)acryloyloxy groups per molecule. Specific examples include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, propylene di(meth)acrylate and polypropylene glycol di(meth)acrylate. In the present specification, the term “di(meth)acrylate” means dimethacrylate and diacrylate. From the viewpoint of improving the refractive index of the plastic optical material, di(meth)acrylate represented by chemical formula (1) is preferably used.
In chemical formula (1), R
1
represents a hydrogen atom or a methyl group, y is 0 or 1, and x and z may be the same or different and each represent an integer of 1 to 5, preferably integer of 1 to 3. When x and/or z is 6 or more, the refractive index and the heat resistance of the resultant resin become considerably low.
As di(meth)acrylate represented by chemical formula (1), for example, there can be mentioned 2,2-bis(4-methacryloxyethoxyphenyl)propane, 2,2-bis[4-(2-methacryloxyethoxy)ethoxy]propane, 2,2-bis[4-(2-methacryloxyethoxy)diethoxy]propane, 2,2-bis[4-(2-methacryloxyethoxy)triethoxyphenyl]propane, 2,2-bis[4-(2-methacryloxyethoxy)tetraethoxyphenyl]propane, 2,2-bis[4-(2-methacryloxyethoxycarbonyloxy)phenyl]propane, and 2,2-bis{4-[(2-methacryloxyethoxy)ethoxycarbonyloxy]phenyl} propane. Di(meth)acrylate can be used singly or in combination. The content of the di(meth)acrylate in the monomer composition is generally 5 to 50% by weight, preferably in the range of from 15 to 45% by weight. When the content is less than 5% by weight, the effect of imparting impact resistance and dyeing properties to the optical material cannot be satisfactorily obtained, and, when the content exceeds 50% by weight, the refractive index of the resultant optical material tends to lower.
The divinylphenyl compound includes divinylbenzene and divinylbiphenyl. The content of the divinylphenyl compound in the monomer composition is generally 5 to 40% by weight, preferably 7 to 30% by weight. When the content is less than 5% by weight, the effect of improving the refractive index of the optical material and imparting heat resistance to the optical material cannot be satisfactorily obtained, and, when the content exceeds 40% by weight, the impact resistance of the resultant optical material tends to
Koinuma Yasumi
Tanaka Katsuyoshi
NOF Corporation
Sergent Rabon
Synnestvedt & Lechner LLP
LandOfFree
Monomer composition for optical plastic optical material,... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Monomer composition for optical plastic optical material,..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Monomer composition for optical plastic optical material,... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2901187