Table A3 Optical Brighteners

R1 and R2 are each Q 12 aliphatic alkyl, cycloaliphatic, araliphatic, or monocyclic aryl radicals and are optionally substituted. Hal is a halogen atom 

Used for optical brightening of PVC, 642 polypropylene, polystyrene, and poly(methyl methacrylate) 

R is a Ci-i alkyl, phenyl, or benzyl group or phenyl or benzyl substituted by Cl or Me 

and R2 may be the same or different and each denotes an optionally substituted sulphonic acid group, a sulphone, cyano-, or modified carboxylic acid group. R2 can also denote an alkyl or alkoxy-group or a H or Cl atom. R1, and R2 , which may be the same or different, each denote a sulphonic acid group or a salt thereof, a H or Cl atom or an alkyl or alkoxy-group 

Used to brighten polyamides, polyesters, polyacrylonitrile, polystyrene, and PVC 

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