Ladas & Parry
Photochromic composition and photochromic resin obtainable by using the same
 A photochromic composition comprising (a) 100 parts by weight of a di(meth)acrylate compound represented by the formula (I): ##STR1## wherein R.sup.1 s each independently represent hydrogen or methyl, R.sup.2 s and R.sup.3 s each independently represent alkylene having 1 to 4 carbon atoms, X represents halogen other than fluorine, Y represents oxygen or sulfur, and m is an integer of 0 to 4, and (b) 0.01 to 5 parts by weight of a photochromic compound. The photochromic composition is excellent in heat resistance, mechanical strength, adhesion to a hard coat layer and moldability, and the photochromic properties thereof is highly resistant to light. By the use of the photochromic composition, a thin and light-weight photochromic lens or the like can be obtained. 
Seiko Epson Corp. Tokuyama Corp.
G C G
G03C C09K G02B
inventional inventional inventional
Hitoshi Tooru Takashi Satoshi Toshiyuki
Mizuno Saito Kobayakawa Kubota Miyabayashi