GB896264A - New stilbene derivatives and process for their manufacture - Google Patents

Abstract

The invention comprises optical brightening agents of the formula <FORM:0896264/IV (b)/1> wherein X, Y and Z denote amino radicals derived from heterocyclic amines or from primary or secondary aliphatic, cycloaliphatic or aromatic amines which may be substituted (e.g. by halogen or by hydroxyl, alkoxy, sulphonic or sulphonamide groups) and which may be identical with the radical V, or the -NH2 group, R denotes hydrogen or the methyl group, R1 denotes hydrogen or a C1-4 alkyl group optionally substituted by hydroxyl, cyano or alkoxy groups, and n is 0 or 1, and salts (e.g. Na salts) thereof. The compounds are prepared by reacting in any desired sequence 2 mols of cyanuric chloride with (a) 1 mol. of 4,41-diaminostilbene-2,21-disulphonic acid or a salt thereof, (b) 1 to 4 mols of one or more cyanalkyl amines of the formula R1-NH-(CH2)n-CH(R)-CN and (c) 0 to 3 mols of one or more primary or secondary amines or ammonia, with the proviso that a total of 4 mols of bases (b) and (c) are used. Alternatively, 1 mol. of cyanuric chloride is reacted in any desired sequence with (a) 1 mol of 4-amino-41-nitrostilbene-2,21-disulphonic acid or a salt thereof, and (b) a total of 2 mols of one or more of primary or secondary amines, ammonia or cyanalkyl amines of the formula R1-NH-(CH2)n-CH(R)-CN the nitro group in the condensation product is reduced to an amino group, and a further mol. of cyanuric chloride is then reacted in any desired sequence with (c) one mol of the amino condensation product thus obtained, and (d) a total of 2 mols of the bases specified under (b), with the proviso that at least 1 mol. of the bases used under (b) and (d) is a cyanalkylamine of the formula R1-NH-(CH2)n-CH(R)-CNALSO:Paper sheets during their formation from a moist paper web in a "size press" in the presence of starch, or during their formation from bleached sulphite cellulose in a "hollander" in the presence of rosin size and aluminium sulphate solutions, and fibres of cotton (cretonne), viscose, nylon and wool in presence of acetic acid or ammonium sulphate, may be treated in conjunction with sizing agents such as dimethyl urea trimethylol melamine, or vinyl, acrylic or styrene polymers, or surface-active agents (e.g. detergents) with optical brightening agents of the formula <FORM:0896264/IV (c)/1> wherein X, Y and Z denote primary amino groups or amino radicals derived from heterocyclic amines or from primary or secondary aliphatic, cycloaliphatic or aromatic amines which may be substituted (e.g. by halogen or by hydroxyl, alkoxy, sulphonic or sulphonamide groups) and which may be identical with the radical V, R denotes hydrogen or methyl, R1 denotes hydrogen or a C1-4 alkyl group optionally substituted by hydroxyl cyano or alkoxy groups, and n is 0 or 1, and salts (e.g. Na salts) thereof.