Patent GB-680924-A (GB)
Title: Dry surface-active compositions
IPC: C11D3/384
Filed: 1950-02-21
Abstract: Solid dry surface-active compositions containing water-soluble salts of alkyl sulphuric acid esters possessing a hydrocarbon radical of 6 to 25 carbon atoms are prepared by adding to an aqueous solution of the salts at least one of the following substances (as hereinafter further characterized) namely a starch, a protein or a polymeric partial hydrolysis product of a starch or protein, and subjecting the resulting mixture in a thin layer to a drying operation on a heated surface.  The starches, proteins and their said products are those having melting or decomposition temperatures above 100 DEG  C. and are capable of being rendered anhydrous; the proteins should also be soluble or dispersible in the liquid to be dried.  Potato, rice, corn, wheat and other vegetable starches, cold-soluble starch, thin-boiling starch, the various grades of dextrin, casein-bearing materials, albumins, gelatine, glue, proteoses, peptones and peptides are specified. The alkyl sulphuric esters may be those obtained by sulphation of fatty alcohols produced by hydrogenation of higher fatty acids, by sulphation of the higher Oxo alcohols or by sulphation of the appropriate alkenes or corresponding secondary alcohols.  The additives may be used in amounts of, e.g., 25-30 up to 200 per cent or more of the alkyl sulphate salts.  If desired, there may be alkali sulphates, phosphates or borates or other readily crystallizing inorganic salts incorporated in the solutions to be dried.  Alkaline substances are preferably added to ensure that the pH of the product does not fall below 7 during the drying.  In examples: (1) and (2) dextrin or cold-soluble starch and some sodium carbonate are added to a solution of secondary alkyl sodium sulphates (average M.W. 315) which is then drum-dried, yielding a flaky or powdery solid; (3) solutions of skimmed milk powder and Glaubers salt are added to a solution of C16 sodium alkyl sulphate and the mixture is dried as in (1), yielding a product in the form of scales.ALSO:Solide detergent compositions containing water-soluble salts of alkyl sulphuric acid esters possessing a hydrocarbon radical of from 6 to 25 carbon atoms are prepared by adding to an aqueous solution of the water-soluble salts at least one of the following substances (as hereinafter further characterized), namely a starch, a protein or a polymeric partial hydrolysis product of a starch or protein, and subjecting the resulting mixture in a thin layer to a drying operation on a heated surface.  The starches, proteins and their said products are those having melting or decomposition temperatures above 100 DEG C and capable of being rendered anhydrous; the proteins should also be soluble or dispersible in the liquid to be dried.  Potato, rice, corn, wheat and other vegetable starches, cold-soluble starch, thin-boiling starch and the various grades of dextrin, and casein-bearing materials, albumins, gelatin, glue, proteoses, peptones and peptides are specified.  The alkyl sulphuric esters may be those obtained by sulphation of fatty alcohols produced by hydrogenation of higher fatty acids, of the higher oxo-alcohols or of the appropriate alkenes or corresponding secondary alcohols. The additives may be used in amounts of e.g., 25-30 per cent up to 200 per cent or more of the sulphuric acid ester salt.  If desired, alkali sulphates, phosphates or borates or other readily crystallizing inorganic salts may be incorporated in the solutions to be dried.  It is preferred to ensure that the pH of the product does not fall below 7 during drying.  In examples (1) and (2) dextrin or cold-soluble starch and some sodium carbonate are added to an aqueous solution of secondary sodium alkyl sulphates (average M.W. 315) and the solution is then drum-dried, yielding a dry flaky or powdery solid; (3) solutions of skimmed milk powder and Glauber's salt are added to a solution of C16 primary sodium alkyl sulphate and the mixture is dried as in (1), yielding a solid product in the form of scales.