Patent ID: 8012596
Filing Date: 2011-09-06
Classification: C08F,G02B,Y10S,Y10T

Abstract:
1. A photochromic lens substrate, which comprises a cured product of a polymerization curable composition comprising: (I) a polyfunctional polymerizable monomer represented by the following formula (1): wherein R 1 is a hydrogen atom or methyl group, the group —R 2 — 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 3 is a trivalent to hexafunctional organic residue, a is an integer of 0 to 3 and b is an integer of 3 to 6; (II) a bifunctional polymerizable monomer represented by the following formula (2): wherein R 4 and R 5 are each independently a hydrogen atom or methyl group, R 6 and R 7 are each independently a hydrogen atom or alkyl group having 1 or 2 carbon atoms, the group —X— is —O—, —S—, —S(═O) 2 —, —C(═O)—O—, —CH 2 —, —CH═CH— or —C(CH 3 ) 2 —, and m and n satisfy (m+n)=0 to 30; and (III) another polymerizable monomer different than the above polymerizable monomers (I) and (II), selected from the group consisting of polyethylene glycol methacrylate having an average molecular weight of 526, polyethylene glycol methacrylate having an average molecular weight of 360, methyl ether polyethylene glycol methacrylate having an average molecular weight of 475, methyl ether polyethylene glycol methacrylate having an average molecular weight of 1,000, polypropylene glycol methacrylate having an average molecular weight of 375, polypropylene glycol methacrylate having an average molecular weight of 430, stearyl methacrylate, lauryl methacrylate, ethylene glycol glycidyl ether, propylene glycol glycidyl ether, tetraethylene glycol diacrylate, nonaethylene glycol diacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, tripropylene glycol dimethacrylate, tetrapropylene glycol dimethacrylate, nonaethylene glycol dimethacrylate, nonapropylene glycol dimethacrylate, ethylene glycol bisglycidyl methacrylate, 1, 4-butylene glycol dimethacrylate, 1, 9-nonylene glycol dimethacrylate, neopentylene glycol dimethacrylate, polyallyl compounds, acrylate and methacrylate compounds, vinyl compounds, bifunctional to hexafunctional polymerizable polyurethane oligomers and bifunctional to hexafunctional polymerizable polyester oligomers; (IV) a photochromic compound; and (V) a thermal polymerization initiator, wherein the amounts of the polyfunctional polymerizable monomer (I), the bifunctional polymerizable monomer (II) and the other polymerizable monomer (III) are 1 to 15 wt %, 10 to 80 wt % and 5 to 89 wt % based on the total of all the polymerizable monomers, respectively, the fading half-life period of the photochromic compound (IV) in the cured product is 30 times or less shorter than the fading half-life period of the photochromic compound (IV) in the polymerization curable composition, and said cured product has a tensile strength of 20 Kgf or more.