METHOD OF PROTECTING POLYURETHANE RESINS FROM DEGRADATION BY ULTRA VIOLET RADIATION

摘要

1477945 5 - Chloro - 2 - (21,41 - dihydroxyphenyl)benzotriazole SUMITOMO CHEMICAL CO Ltd 7 Feb 1975 [8 Feb 1974] 5396/75 Heading C2C [Also in Division C3] The compound of formula is prepared by the reduction of a nitroazo compound of formula e.g. using reducing metals such as Zn, Sn and Fe to an alkaline solution. 4 - Chloro - 2 - nitro - 21,41 - dihydroxyazobenzene is prepared by reaction of diazotized 4-chloro-2-nitroaniline and resorcinol.