Patent ID: 8691926

Claim:
A polymerization curable composition comprising: (I) 100 parts by mass of a polymerizable monomer composition consisting of: (I-1) 10 to 80 mass % of a bifunctional polymerizable monomer represented by the following formula (1), wherein R 1 and R 2 are each independently a hydrogen atom or methyl group, R 3 and R 4 are each independently hydrogen atom or alkyl group having 1 or 2 carbon atoms, —X— is —O—, —S—, —S(═O) 2 —, —C(═O)—O—, —CH 2 —, —CH═CH— or —C(CH 3 ) 2 —, and m and n are each independently an integer which satisfies (m+n)=2 to 30, (I-2) 1 to 15 mass % of a polyfunctional polymerizable monomer represented by the following formula (2), wherein R 5 is a hydrogen atom or methyl group, —R 6 — is —CH 2 CH 2 O—, —CH 2 CH(CH 3 )O— or —C(═O)CH 2 CH 2 CH 2 CH 2 CH 2 O—, R 7 is a tervalent to hexavalent organic residue, a is an integer of 0 to 3, and b is an integer of 3 to 6; and (I-3) 5 to 89 mass % of a polymerizable monomer other than (I-1) and (I-2); (II) 0.001 to 5 parts by mass of a photochromic compound; and (III) 0.001 to 0.5 part by mass of a light stabilizer which is a compound having a 2,2,6,6-tetramethyl-4-piperidyl skeleton.