Aufhellmittel fuer Polyester

摘要

Optical brighteners which may be incorporated in polyester moulding or spinning compositions comprise oxazoles of the formula wherein R1 is a substituted or unsubstituted p-phenylene radical, R2 is an aromatic radical containing a single benzene ring which may be substituted and is condensed with one oxazole ring, and R2 is a substituted or unsubstituted naphthalene radical condensed with the other oxazole ring. Example 2 relates to a spinning mass based on a polyterphthalic acid ethyleneglycol ester.ALSO:The invention comprises compounds of the formula wherein X is a hydrocarbon radical, a chlorine atom or an alkoxy group and Y represents hydrogen or together with X forms a saturated carbocyclic ring condensed with the benzene ring. These, and compounds (which are free from acid groups imparting water solubility) of the more general formula where R is a substituted or unsubstituted p-phenylene radical, R2 is an aromatic radical containing a single benzene ring which may be substituted and is condensed with the oxazole ring and R3 is a substituted or unsubstituted naphthalene residue condensed with the oxazole ring, are prepared by reacting 1 mol. of an orthohydroxyaminoaryl compound (4) with 1 mol. of carboxylic acid (5). The compounds are used as optical brightening agents for polyester materials (see Divisions D1 and C3). A large number of compounds are specified. The carboxylic acids of the Formula (5) are prepared by condensing vic-aminohydroxyaryl compounds with an alkylester of carboxychloride benzoic acid followed by hydrolysis of the alkyl group.ALSO:Polyester material is optically brightened by incorporating therein, or fixing thereon, an oxazole compound which is free from acid groups which impart water solubility and has the formula wherein R1 represents a substituted or unsubstituted p-phenylene radical, R2 is an aromatic radical containing a single benzene ring which may be substituted and is condensed with the isoxazole ring and R3 is a substituted or unsubstituted naphthalene residue condensed with the oxazole ring. It is p preferred to apply the brightener using an aqueous suspension of the oxazole compound, which may contain a carrier and/or dispersant, maintained at 50 DEG -100 DEG C. The treated material is dried and may be subjected to heating up to 225 DEG C. Example 1 describes the treatment of a polyester fabric.