摘要:
An article may be temporarily colored by application of an aqueous solution of a polyoxyalkylene substituted chromophore characterized by a C = N pair with an electron withdrawing group bonded to one element of the pair and an electron donating group bonded to the opposite element. The polyoxyalkylene substituent imparts solubility to the colorant and bulk to prevent penetration into interstices in the article being colored. The colorant may be subsequently decolorized by hydrolysis when an aqueous acid solution is applied to the colorant.