Patent GB-683527-A (GB)
Title: Improvements in or relating to auxiliary washing agents
Inventor: LIND OTTO
IPC: C11D3/08
Filed: 1949-02-25
Abstract: An auxiliary washing composition, which is a dry powder free from oxygen-evolving substances and does not contain soaps or other detergents, comprises an alkaline reacting salt, e.g. soda, and up to about 20 per cent, preferably 2-10 per cent, of magnesium silicate, which is colloidally soluble in water. Magnesium metasilicate is preferably used, and minor quantities, preferably 1-5 per cent, of alkali metal salts of phosphoric acids more anhydrous than orthophosphoric acid may also be present, as well as sodium meta-silicate and neutral salts, e.g. sodium chloride or sulphate. The compositions may be added to baths for washing clothes or to baths for soaking clothes before washing.  In examples: (1) magnesium silicate, obtained by precipitating magnesium chloride with sodium metasilicate and drying, is sprinkled into water at 70-80 DEG  C. and anhydrous soda is added; the composition is cooled and pulverized; (2) magnesium silicate, precipitated from sodium metasilicate solution by magnesium chloride, is washed and dried at 100 DEG  C., added to anhydrous soda and sodium pyrophosphate, and the mixture pulverized; (3) sodium metasilicate is stirred into a solution of magnesium chloride and anhydrous soda is added; the composition is pulverized after solidification.  Specification 683,526, [Group III], is referred to.ALSO:An auxiliary washing composition, which is a dry powder free from oxygen-evolving substances and does not contain soaps or other detergents, comprises an alkaline reacting salt, e.g. soda, and up to about 20 per cent, preferably 2-10 per cent, of magnesium silicate which is collidally soluble in water. Magnesium metasilicate is preferably used, and minor quantities, preferably 1-5 per cent, of alkali metal salts of phosphoric acids more anhydrous than orthophophoric acid may also be present, as well as sodium metasilicate and neutral salts, e.g. sodium chloride or sulphate. The magnesium silicate may be precipitated in suspension in a solution of the other components of the composition and the product reduced to a dry powder by known methods, or ready-formed magnesium silicates may be mixed with the other constituents in powdered form. The compositions may be added to baths for washing clothes or to baths for soaking clothes before washing.  In examples, (1) magnesium silicate, obtained by precipitating magnesium chloride with sodium metasilicate and drying, is sprinkled into water at 70-80 DEG C and anhydrous soda is added; the composition is cooled and pulverized; (2) magnesium silicate, precipitated from sodium metasilicate solution by magnesium chloride, is washed and dried at 100 DEG C, added to anhydrous soda and sodium pyrophosphate, and the mixture pulverized; (3) sodium metasilicate is stirred into a solution of magnesium chloride and anhydrous soda is added; the composition is pulverized after solidification.  Use may also be made of magnesium silicates prepared by treating silica gel with boiling magnesium chloride solution in the presence of alkaline substances. Specification 683,526 is referred to.ALSO:A water-softening composition, which is a dry powder free from oxygen-evolving substances and does not contain soaps or other detergents, comprises an alkaline reacting salt, e.g. soda, and up to about 20 per cent, preferably 2-10 per cent, of magnesium silicate which is colloidally soluble in water.  Magnesium metasilicate is preferably used, and minor quantities, preferably 1-5 per cent, of alkali metal salts of phosphoric acids more anhydrous than orthophosphoric acid may also be present, as well as sodium metasilicate and neutral salts, e.g. sodium chloride or sulphate.  In examples, (1) magnesium silicate, obtained by precipitating magnesium chloride with sodium metasilicate and drying, is sprinkled into water at 70-80 DEG C and anhydrous soda is added: the composition is cooled and pulverized; (2) magnesium silicate, precipitated from sodium metasilicate solution by magnesium chloride, is washed and dried at 100 DEG C, added to anhydrous soda and sodium pyrophosphate, and the mixture pulverized; (3) sodium metasilicate is stirred into a solution of magnesium chloride and anhydrous soda is added: the composition is pulverized after solidification.  Use may also be made of magnesium silicates prepared by treating silica gel with boiling magnesium chloride solution in the presence of alkaline substances.  Specification 683,526, [Group III], is referred to.