GB1022680A - Improvements in or relating to detergent briquettes - Google Patents

Abstract

Detergent briquettes consist of three layers, the first and third layers being outer layers each comprising a compressed material which itself comprises one or more functional ingredients of the detergent briquette and which, on compression, produces a relatively smooth, abrasion resistant surface, and the second layer being an inner layer comprising a built detergent composition which is a mixture of one or more particulate inorganic builder salts and a particulate detergent composition, and which would produce, if compressed alone, a rougher and more easily abraided surface than that produced by either of the outer layers, the mixture being produced in the absence of liquid or in the presence of insufficient liquid to destroy the particulate nature of the mixture, the second layer constituting at least 50%, by weight, of the briquette. The briquettes are produced by superposing the three layers in the die-box of a briquetting press, and then compressing the layers together. The layers may be of different colours, and the first and third layers may be of the same functional composition. The ingredients of each layer are chosen merely to satisfy the above requirements, provided that the whole briquette is of suitable composition. In examples, the inner layer is composed of two or more of the following:-sodium tripolyphosphate, sodium silicate, sodium perborate, soap, sodium dodecyl benzene sulphonate, sodium tallow alkyl sulphate, lauric acid monoethanolamide, coconut fatty acid amide, sodium carboxy methyl cellulose, tetra sodium salt of EDTA, and water, but may also contain alkali metal pyrophosphates, orthophosphates, and carbonates, sodium sulphate, and aqueous sodium silicate or starch as binding agent instead of water; whilst the outer layers comprise one or more of the following:-sodium tripolyphosphate, trisodium phosphate, sodium sulphate, sodium silicate, sodium perborate, soap, sodium toluene sulphonate, sodium dodecyl benzene sulphonate, coconut and lauric fatty acid monoethanolamides, cetyl alcohol, and water, but may also contain fatty acids and amides. Preferably the inner layer is 85-95% of the whole briquette.