| 摘要 |
1281796 Scouring powder UNILEVER Ltd 19 April 1971 [24 Feb 1970] 22349/71 Heading C5D A scouring powder including a bleach and a colouring agent to indicate whether the bleach is still active is made by spraying an aqueous dispersion of the colouring agent on to a particulate water-soluble inorganic hydrate-forming salt and mixing the coloured product with an abrasive and a bleach. The dye may be naphthalene green or acid green. It may be dissolved in water, heated to 50-90‹ C. and then sprayed whilst still hot. The inorganic salt may be an alkali metal carbonate, sodium orthophosphate, disodium hydrogen phosphate or sodium tripolyphosphate. The sprayed inorganic salt may be ground to less than 0À2 mm. particle size before mixing with the bleach and abrasive. The bleach may be trichlorooyanuric acid. The abrasive may be calcite or felspar. The composition may also include a surfactant, e.g. a sodium alkyl benzene sulphonate, a perfume and another dye. |
