A resin composition, the resin composition comprising a prepolymer (209) and optionally one or more diluent(s) (FIG. 3A), the prepolymer (209) comprising repeating units having at least one carbonate linkage and at least one unsaturated side-chain, the at least one optional diluent(s) comprising at least one unsaturated side-chain, wherein either or both of the prepolymer (209) and the at least one optional diluent(s) comprises at least one O═C—N linkage, preferably a urethane linkage.

A method of preparing a low bubbling and low yellowing, high refractive index polyurethane or polythiourethane is provided. A method of evaluating an aromatic polyiso(thio)cyanate material, such as an aromatic diisocyanate, e.g., m-xylylene cyanate, is provided. The method evaluates transmittance in a sample of the isocyanate to determine if the aromatic polyiso(thio)cyanate material will lead to unacceptable bubbling or yellowing in a high refractive index or high Abbe number polymer composition.

A polymerizable composition for optical materials of the present invention includes a polymer (a) comprised of one or more compounds selected from compounds represented by the following General Formulas (1) to (4), a compound (b) of which light absorption characteristics vary by sensing changes in environment; and a polymerization reactive compound (c) (except for the polymer (a)). ##STR00001##

A xylylene diisocyanate, a compound represented by the following chemical formula (1), and a compound represented by the following chemical formula (2) are contained in a xylylene diisocyanate composition.

##STR00001##

An internal release agent includes at least one phosphodiester represented by the following general formula (1).

##STR00001##

In the formula, R.sub.1 and R.sub.2 independently represent a hydrocarbon group having 1 to 30 carbon atoms, which is optionally substituted with at least one hydroxyl group, and R.sub.3 represents an alkylene group having 2 to 4 carbon atoms. A plurality of R.sub.3's may be the same as or different from each other. M represents a hydrogen atom, an ammonium ion, an alkali metal ion, or a monovalent/divalent alkali earth metal ion, and n is an integer of 1 to 60.

Embodiments of the disclosure generally provide compositions and methods related to oligomeric and polymeric urethane materials that contain hydrolyzable polythioaminal groups for use in biomedical applications.

An embodiment relates to an isocyanate composition with improved stability and reactivity and a plastic optical lens using the same. The isocyanate composition has improved stability since the content of chlorine in the composition is adjusted to 22-500 ppm, and thus the isocyanate composition can prevent the deterioration in reactivity even in the long-term storage. Therefore, the isocyanate composition according to an example, even when used after long-term storage after preparation, can be prepared, through polymerization with a thiol-based compound, as a polythiourethane-based optical material with excellent physical properties, such as refractive index, Abbe number, transparency, glass transition temperature, and yellowness, and thus the isocyanate composition is useful in fields of glass lenses, a camera lens, and the like.

One embodiment according to the present disclosure relates to a spectacle lens containing a compound in which the transmittance of light with a wavelength of 410 nm is 5% or less and the transmittance of light with a wavelength of 430 nm is 70% or more under the following transmittance measurement conditions.

transmittance measurement conditions: for a sample containing a standard resin from curing 50.28 parts by mass of a mixture of 2,5-bis(isocyanatomethyl)-bicyclo[2.2.1]heptane and 2,6-bis(isocyanatomethyl)-bicyclo[2.2.1]heptane and a mixture of 25.50 parts by mass of pentaerythritol tetrakis(3-mercaptopropionate) and 24.22 parts by mass of 1,2-bis(2-mercaptoethylthio)-3-mercaptopropane and 0.55 parts by mass of the above compound with respect to 100 parts by mass of the standard resin, the sample having a thickness of 1.6 mm at the measurement point, the transmittance of light with a wavelength of 410 nm and 430 nm is measured with a spectrophotometer.

One embodiment of the present invention can provide an optical material composition that includes a cyclic compound that is represented by formula (1) and an episulfide that is represented by formula (2). Another embodiment of the present invention can provide an optical material production method that includes a step wherein, with respect to the total amount of the optical material composition, 0.0001-10 mass % of a polymerization catalyst is added to the optical material composition and the optical material composition is polymerization cured. (In formula (2), m is an integer from 0 to 4, and n is an integer from 0 to 2.)

##STR00001##

The invention relates to a composition which forms an insulating layer and which contains a binder based on polyurea. The inventive composition, which has a relatively high expansion rate, allows application, in a simple and rapid manner, of coatings having the layer thickness required for the particular fire resistance time, it being possible to reduce the layer thickness to a minimum and nevertheless to achieve high insulating action. The inventive composition is particularly suitable for fire protection, especially as a coating for metallic and nonmetallic substrates, for instance steel components such as pillars, beams and bars, for increasing the fire resistance time.