A polymerizable composition for optical materials of the present invention contains (A) a polyisocyanate compound, (B) a polythiol compound, (C) a photochromic compound, (D) a polyether compound having a number-average molecular weight of 50 to 10,000, and (E) a polyether-modified siloxane compound having a viscosity of 1 mPa.Math.s or more and less than 1,600 mPa.Math.s.

A polymerizable composition for optical materials of the present invention contains (A) a polyisocyanate compound, (B) a polythiol compound, (C) a photochromic compound, (D) a polyether compound having a number-average molecular weight of 50 to 10,000, and (E) a polyether-modified siloxane compound having a viscosity of 1 mPa.Math.s or more and less than 1,600 mPa.Math.s.

An embodiment relates to an aromatic polythiol compound for optical materials, and the aromatic polythiol compound according to the embodiment contains a phenyl group and a large number of sulfur atoms in its polythiol structure so that a polymerizable composition and an optical material obtained therefrom have excellent optical properties such as high refractive index and low specific gravity, as well as excellent mechanical properties such as low cure shrinkage; thus, they can be advantageously used for producing various plastic optical lenses such as eyeglass lenses and camera lenses.

An embodiment relates to an aromatic polythiol compound for optical materials, and the aromatic polythiol compound according to the embodiment contains a phenyl group and a large number of sulfur atoms in its polythiol structure so that a polymerizable composition and an optical material obtained therefrom have excellent optical properties such as high refractive index and low specific gravity, as well as excellent mechanical properties such as low cure shrinkage; thus, they can be advantageously used for producing various plastic optical lenses such as eyeglass lenses and camera lenses.

The invention relates to compounds and methods for extending the pot life of mixtures of isocyanates and isocyanate-reactive compounds when using acidic phosphoric acid ester as a mould release agent.

The invention relates to compounds and methods for extending the pot life of mixtures of isocyanates and isocyanate-reactive compounds when using acidic phosphoric acid ester as a mould release agent.

Isocyanate-terminated chain-extended polythioether prepolymers, compositions thereof, and methods of use thereof are disclosed. The isocyanate-terminated chain-extended polythioether prepolymers are useful in sprayable coatings and sealants and especially sprayable coatings and sealants having a high filler content.

Actinic radiation-curable compositions containing polythiols and urethane/urea-containing polyalkenyl prepolymers that can be used for aerospace coatings and sealants. The coatings can be applied to surfaces and rapidly cured.

Actinic radiation-curable compositions containing polythiols and urethane/urea-containing polyalkenyl prepolymers that can be used for aerospace coatings and sealants. The coatings can be applied to surfaces and rapidly cured.

Actinic radiation-curable compositions containing polythiols and urethane/urea-containing polyalkenyl prepolymers that can be used for aerospace coatings and sealants. The coatings can be applied to surfaces and rapidly cured.