Verfahren zur Herstellung eines optischen Aufhellungsmittels.

摘要

Natural and artificial fibres and films are brightened by the application of a fluorescent pyrazoline compound of the general formula in which R1 is hydrogen, a furyl residue or an unsubstituted or substituted hydrocarbon group but excluding nitro-substituted groups, Ar1 is an unsubstituted or substituted aromatic hydrocarbon residue but excluding such residues containing sulphonic, carboxylic, nitro or cyano groups, and Ar2 is an unsubstituted or substituted aromatic hydrocarbon residue but excluding nitro-substituted residues, which compound is colourless in aqueous or alcoholic solution. Particularly favourable are compounds in which R1 or Ar2 contain carboxylic or sulphonic acid groups which in the form of their salts are substantive to the fibres and films and as free acids are substantive to protein and polyamide fibres. Many compounds falling within the general formula given are specified, including compounds in which R1 or Ar2 is phenyl, m-tolyl, methyl, p-chlorophenyl-phenyl, p-methoxyphenyl, p-sulphophenyl, p-chlorophenyl, m-sulphophenyl, p-methyl-m-sulphophenyl, p-methyl-o-sulphophenyl, 4-sulpho-2, 5-dichlorophenyl-4, 8-disulphonaphthyl, o-sulphophenyl, p-acetamidophenyl or furyl, and in which Ar1 is phenyl, m-tolyl, p-bromophenyl, p-tolyl, p-methoxyphenyl, p-ethoxyphenyl, p-phenoxyphenyl, p-phenylphenyl, p-ethoxy-m-methylphenyl, p-chlorophenylphenyl, p-methoxyphenyl or p-chlorophenyl. The compounds may be applied to white materials to improve the whiteness, or to dyed materials to improve the colour. In the case of artificial fibres and films, the compounds may be applied at any stage, e.g. they may be incorporated in cellulose acetate compositions before extruding or casting.ALSO:Natural and artificial fibres and films are brightened by the application of a fluorescent pyrazoline compound of the general formula in which R1 is hydrogen, a furyl residue or an unsubstituted or substituted hydrocarbon group but excluding nitro-substituted groups, Ar1 is an unsubstituted or substituted aromatic hydrocarbon residue but excluding such residues containing sulphonic, carboxylic, nitro or cyano groups, and Ar2 is an unsubstituted or substituted aromatic hydrocarbon residue, but excluding nitro-substituted residues, which compound is colourless in aqueous or alcoholic solution. Particularly favourable are compounds in which R1 or Ar2 contain carboxylic or sulphonic acid groups which in the form of their salts are substantive to the fibres and films and as free acids are substantive to protein and polyamide fibres. Many compounds falling within the general formula given are specified, including compounds in which R1 or Ar2 is phenyl, m-tolyl, methyl, p-chlorophenylphenyl, p-methoxyphenyl, p-sulphophenyl, p-chlorophenyl, m-sulphophenyl, p - methyl - m - sulphophenyl, p-methyl-o-sulphophenyl, 4-sulpho-2,5-dichlorophenyl, 4,8-disulphonaphthyl, o-sulphophenyl, p-acetamidophenyl or furyl, and in which Ar is phenyl, m-tolyl, p-bromophenyl, p-tolyl, p-methoxyphenyl, p-ethoxyphenyl, p-phenoxyphenyl, p-phenylphenyl, p-ethoxy-m-methylphenyl, p - chlorophenylphenyl, p - methoxyphenyl or p-chlorophenyl. The compounds may be prepared by the process of Specification 669,591; by the condensation of an aryl hydrazine with a reaction product obtained from an acetophenone, formaldehyde and an amine; or by the condensation of a ketone of the type Ar-CO-CR=CH2 with an aryl hydrazine.ALSO:Natural and artificial fibres and films are brightened by the application of a fluorescent pyrazoline compound of the general formula in which R1 is hydrogen, a furyl residue or an unsubstituted or substituted hydrocarbon group but excluding nitro-substituted groups, Ar1 is an unsubstituted or substituted aromatic hydrocarbon residue but excluding such residues containing sulphonic, carboxylic, nitro or cyano groups, and Ar2 is an unsubstituted or substituted aromatic hydrocarbon residue but excluding nitro-substituted residues, which compound is colourless in aqueous or alcoholic solution. Particularly favourable are compounds in which R1 or Ar2 contains carboxylic or sulphonic acid groups, which in the form of their salts are substantive to the fibres and films and as free acids are substantive to protein and polyamide fibres. Many compounds falling within the general formula given are specified, including compounds in which R1 or Ar2 is phenyl, m-tolyl, methyl, p-chlorophenylphenyl, p-methoxyphenyl, p-sulphophenyl, p-chlorophenyl, m-sulphophenyl, p - methyl - m - sulphophenyl, p - methyl - o - sulphophenyl, 4 - sulpho - 2,5 - dichlorophenyl, 4,8 - disulphonaphthyl, o - sulphophenyl, p-acetamidophenyl or furyl, and in which Ar1 is phenyl, m-tolyl, p-bromophenyl, p - tolyl, p - methoxyphenyl, p - ethoxyphenyl, p - phenoxyphenyl, p - phenylphenyl, p - ethoxy - m - methylphenyl, p - chlorophenylphenyl, p-methoxyphenyl or p-chlorophenyl. The compounds may be applied to white materials to improve the whiteness, or to dyed materials to improve the colour. In the case of artificial fibres and films, the compounds may be applied at any stage, e.g. they may be incorporated in cellulose acetate compositions before extruding or casting.