GB604990A - Improvements in cleansing compositions - Google Patents

Abstract

Cleansing compositions, particularly for artificial dentures, comprise an oxygen-liberating compound other than an alkali-metal percarbonate, an activating agent and an alkaline material, the ingredients being so proportioned that a dilute aqueous solution of the composition has a pH of from 9.0 to 10.5. The alkaline material, e.g. sodium carbonate and sodium bicarbonate may function as a buffer to maintain the pH within the above range and preferably within the range 9.2 to 10.2. The oxygen liberating compound may be an alkali metal perborate, perpyrophosphate or urea peroxide, and the activating agent may comprise a water-soluble alkali-stable substance coated with a material, e.g. an organic carboxylic acid not more than slightly soluble in water but capable of forming water-soluble salts with alkalis, capable of preventing interaction between the oxidising compound and the activating agent during storage. The activating agent may be a complex of a hydroxycarboxylic acid, e.g. gluconic acid with a metal, e.g. cobalt which is capable of existing in at least two states of oxidation. Methods are given for the preparation of cobalto-gluconate and similar complexes and for coating them with higher fatty acids. The composition may include a wetting agent and a dye, e.g. phenol phthalein, which will become colourless after the composition has been dissolved in water for a predetermined period. One of the compositions exemplified consists of 250 parts by weight sodium perborate monohydrate, 125 p of sodium carbonate and bicarbonate respectively, 10 of an activating agent, and 0.1 of sodium lauryl sulphate.