Hard coating compsn. esp. for plastic lenses

摘要

A coating compsn. (I) which gives a hardened prod. with a high refractive index (RI) contains (1) 10-70 wt.% fine particles of the oxide(s) or mixed oxides of Si, Fe, Ti, Ce, Zr, Sb, Zn and/or Sn. (2) 5-90 wt.% of an epoxy gp.-contg. Si cpd. or a partial hydrolysis prod. thereof. (3) 1-45 wt.% of an organic cpd. which is soluble in water or 1-4C alcohol, contg. an OH or SH gp., at least one -O-, -COO-, -S-, -COS- and/or -CSS- gp. in the main chain and at least one unsatd. gp., and (4) a hardening catalyst. Also claimed are coated objects consisting of a transparent substrate with a RI of not less than 1.50, coated with a hardened layer of (I).