Photochromic compounds of the formula <IMAGE> wherein one of R1 and R2 is halogen or lower alkoxy, and the other is hydrogen, and R3 and R4 are hydrogen, lower alkyl, lower alkoxy, or halogen and their use in lenses are disclosed.
申请公布号
AU5024479(A)
申请公布日期
1980.03.13
申请号
AU19790050244
申请日期
1979.08.23
申请人
AMERICAN OPTICAL CORP
发明人
RICHARD J. HOVEY;NORI Y.C. CHU;CHARLES H. FUCHSMAN;PETER G. PIUSZ
