| abstract |
1388492 Methin dyes MINNESOTA MINING & MFG CO 31 Aug 1972 [3 Sept 1971] 40496/72 Heading C4P [Also in Divisions G2 and C3] s-Triazines capable of generating free radicals on stimulation by actinic radiation in the 330- 700 mÁ wavelength range comprise at least one mono-, di- or tri-halomethyl group and at least one chromophoric moiety conjugated with the triazine ring by ethylenic unsaturation. Preferred dyes are of formula (in which Q is Br, or Cl, P is -CQ 3 , -NH 2 , -NHR, -NR 2 or -OR; R is phenyl or 1-6 C alkyl; n is 1-3; W is an optionally substituted aromatic or heterocyclic nucleus or of Formula (II) Z is O or S; R<SP>1</SP> is H, 1-6 C alkyl or phenyl). The dyes are prepared by conventional condensation reactions and used as photoinitiators in photosensitive compositions (see Divisions G2- G3 and C3). In specified dyes Q is Cl; P is CCl 3 or NH 2 ; n is 1-3; W is Formulae II above in which Z is O and R<SP>1</SP> is C 2 H 5 , is phenyl which may be substituted by Cl, N(CH 3 ) 2 , amyloxy or mono- or di-methoxy, or is 1-methyl-2-(pmethoxyphenyl)-indol-3-yl. |