Composition of Enhanced Stability and a Process for Making such a Composition
The invention relates to a laundry detergent shading composition that has been coated with a polymer that serves to promote the stability of the dye.
1 . A granule, for use in the preparation of a basic laundry detergent shading composition, said granule having improved storage properties comprising:
a dye selected from the group consisting of acid dyes, direct dyes, basic dyes, solvent dyes, hydrolised reactive dyes, reactive dyes and disperse dyes and having a dye chromophore type of diarylmethane, triarylmethane, diazines, oxazines, or thiazines.
and, a component selected from the group consisting of: a cogranulent, a binder and a coating,
characterised in that the component is an acidic component.
2 . A granule according to claim 1 , wherein the dye is selected from: an acid dye and a direct dye.
3 . A granule according to claim 1 , wherein the dye is in the form of pregranules comprising the dye and a neutral water soluble material.
4 . A granule according to claim 1 , wherein the acidic component is a water soluble acidic polymer, said polymer having a water solubility greater than 5 g/l at 20° C., a molecular weight of from 1000 to 250000, and wherein a 1% solution of said polymer has a pH of less than 7.
5 . A granule according to claim 4 , wherein the water soluble acidic polymer is a polymer formed from the polymerisation of an unsaturated compound containing a carboxylic acid.
6 . A granule according to claim 5 , wherein the water soluble acidic polymer is a copolymer of acrylic acid and maleic acid.
7 . A granule according to claim 1 , wherein the dye is acid violet 15, 16, 17, 19, 21, 23, 24, 25, 38, 50, 72, and basic violet 1, 2, 3, 4, 5, 6, 7, 9, 13, 14, 15, 16, 17, 23, 27, 40, 43, 45, and 47.
8 . A granule according to claim 1 , wherein the dye is an acid selected from the group consisting of: acid violet 17, acid blue 3, acid blue 9, acid blue 7, and acid blue 10.
9 . A granule according to claim 1 , wherein the granule forms a part of a laundry detergent shading composition, wherein a unit dose provides alkalinity in the pH range 8 to 11 when it dissolves in an aqueous wash volume.
10 . A granule according to claim 9 , wherein the laundry detergent shading composition is in the form of a tablet.
11 . A granule according to claim 1 , wherein buffer capacity wherein when 1.00 gm of the granules are dissolved in 50 ml of demineralised water to provide an acidic solution at least 10 ml of a 0.01 M solution of sodium hydroxide is required to bring the pH of the acidic solution to 9.