Sulphone-substituted derivatives of pyrazoline

摘要

Brightening agents which can be incorporated in moulding or spinning masses used for the production of formed bodies such as foils, fibres or filaments or in plastic masses, e.g. soft polyvinyl chloride, comprise compounds of formula in which R1 and R2 represent hydrogen or halogen atoms or alkoxy radicals, R3 is a hydrogen atom or unsubstituted phenyl radical, and R4 is an alkyl radical which may be substituted by cyano, carboxyl, sulphone or alkyl substituted amino groups. In Example (2), 1 - (p - methylsulphonylphenyl) - 3 - p - (chlorophenyl)-pyrazoline is incorporated on a roller mill into opaque soft polyvinyl chloride. The concentration of brightening agent is generally far below 1% by weight of the material to be brightened. Specifications 669,590 and 808,113 are referred to.ALSO:The invention comprises compounds of formula in which R1 and R2 are hydrogen or halogen atoms, or alxoxy radicals R4 is a hydrogen atom or unsubstituted phenyl radical, and R4 is an alkyl radical which may be substituted by cyano, carboxyl, sulphone or alkyl substituted amino groups, and the preparation thereof by the action of sulphone group containing phenyl hydrazines on vinyl aryl ketones, o -halopropiophenones or the salts of aminoethylaryl ketones, or in some cases by reacting substituted styrenes with 3-aryl sydnones. The pyrazoline compounds are nearly colourless, blue-fluorescent substances and are used as brightening agents. (See Divisions C3 and D1. Specifications 669,590 and 808,113 are referred to.ALSO:Brightening agents for paper, leather and textile materials, especially synthetic fibres, e.g. polyacrylonitrile, polyamide or allulose ester fibres, comprise compounds of formula in which R1 and R2 represent hydrogen or halogen atoms, or alkoxy radicals, R3 is a hydrogen atom or unsubstituted phenyl group, and R4 is an alkyl radical which may be substituted by cyano, carboxyl, sulphone or alkyl substituted amino groups. The compounds are used in aqueous solutions or dispersions, or in solution in organic solvents. Example 1 illustrates the use of 1-(p-methylsulphonyliphenyl)-3-phenylpyrazoline in aqueous solution in treating polyacrylonitrile or cellulose acetate fibres. The concentration of brightening agents is generally far below 1% by weight of the material to be brightened. They may be used in combination with washing agents. Specifications 669,590 and 808,113 are referred to.