Abstract: The present invention provides a cyclic sulfide compound represented by a general formula (I) ##STR1## (where R.sup.1 represents --CH.sub.2 --CH.sub.2 --, --CH.sub.2 --CH.sub.2 --CH.sub.2 --, --CH.sub.2 --O--CH.sub.2 --, --CH.sub.2 --O--, or --CH.sub.2 --S--). According to this invention, a novel cyclic sulfide compound which gives high refractive index and high Abbe number can be obtained. The polymerizable compositions for manufacturing optical products with this compound as their main component can be readily molded into plastic lenses which give superhigh refractive indices and high Abbe numbers or those which give high refractive indices and high Abbe number with low sp.grs. in addition thereto. The castings obtained from said polymerizable compositions are useful as plastic lenses for glasses, manifesting optical uniformity and being excellent in processability, transparency, and thermal, impact and light resistance.

Abstract: The present invention provides a cyclic sulfide compound represented by a general formula (I) ##STR1## (where R.sup.1 represents --CH.sub.2 --CH.sub.2 --, --CH.sub.2 --CH.sub.2 --CH.sub.2 --, --CH.sub.2 --O--CH.sub.2 --, --CH.sub.2 --O--, or --CH.sub.2 --S--). Polymerizable compositions for manufacturing optical products with this compound as their main component can be readily molded into plastic lenses which give superhigh refractive indices and high Abbe numbers or those which give high refractive indices and high Abbe number with low sp.grs. in addition thereto. The castings obtained from said polymerizable compositions are useful as plastic lenses for glasses, manifesting optical uniformity and being excellent in processability, transparency, and thermal, impact and light resistance. Further these polymerizable resin compositions are usable preferably as such optical products as prisms, optical fibers, optical disc substrates, color filters, or infrared absorption filters.

Abstract: A polymerizable composition is provided which is constituted by adding isocyanate by 0.1 to 2 equivalent to the alcoholic hydroxyl group in a mixture dissolving component A prescribed below by 20 to 60 parts by weight to a total of 80 to 40 parts by weight of component B and component C in the ratio specified below:[Component A]A multifunctional (meth)acrylate possessing at least one alcoholic hydroxyl group, and also possessing at least one aromatic ring replaced by at least one halogen atom other than fluorine or phenyl group, and two or more (meth)acryloyl groups in a molecule:[Component B]A multifunctional (meth)acrylate possessing at least one aromatic ring having neither halogen atom nor phenyl group as substituent, and possessing two or more (meth)acryloyl groups in a molecule, or a mixture of radically polymerizable multifunctional unsaturated monomer including the compound; 5 to 80 wt.