Patent GB-658616-A (GB)
Title: A process for the production of fine non-coherent powders containing surface-active substances
IPC: C11D17/06
Filed: 1948-03-18
Abstract: A process for the production of surface-active compositions in the form of fine, non-coherent powders starting from dry or substantially dry surface-active substances which are secondary sulphuric acid alkyl ester salts, or mixtures thereof with inorganic salts, the particles of which substances display a tendency to stick together, comprises grinding these substances in the presence of a substance added to them which in finely-divided condition shows no or only little tendency to stick together.  The substance to be added may be alkali metal or ammonium sulphates, phosphates or chlorides, or talc, kaolin or bentonite, but anhydrous sodium sulphate is preferred.  In an example a dry powder containing 60 per cent of ester salt and 40 per cent of sodium sulphate, formed by atomization-drying of an aqueous secondary sodium alkyl sulphate solution, is ground with an equal quantity of sodium sulphate.  The Specification as open to inspection under Sect. 91 comprises also the use of the process with other surface-active substances such as primary sulphuric acid ester salts, alkyl sulphonates, alkyl aryl sulphonates and sulpho-succinic acid ester salts.  In an example, sodium salt of sulpho-succinic acid di-octyl ester is ground together with bentonite or talc.  This subject-matter does not appear in the Specification as accepted.ALSO:A process for the production of surface-active compositions in the form of fine, non-coherent powders starting from dry or substantially dry surface-active substances which are secondary sulphuric acid alkyl ester salts, or mixtures thereof with inorganic salts, the particles of which substances display a tendency to stick together, comprises grinding these substances in the presence of a substance added to them which in finely-divided condition shows no or only little tendency to stick together.  The substance to be added may be alkali metal or ammonium sulphates, phosphates or chlorides, or talc, kaolin or bentonite, but anhydrous sodium sulphate powder is preferred.  In an example given, a dry powder containing 60 per cent of ester salt and 4 per cent of sodium sulphate, formed by atomization-drying of an aqueous secondary sodium alkyl sulphate solution, is ground with an equal quantity of sodium sulphate.  The Specification as open to inspection under Sect. 91 comprises also the use of the process with other surface-active material such as primary sulphuric acid ester salts, alkyl sulphonates, alkyl aryl sulphonates and sulphosuccinic acid ester salts.  A further example is given in which the sodium salt of sulphosuccinic acid di-octyl ester is ground with bentonite or talc. This subject-matter does not appear in the Specification as accepted.ALSO:A process for the production of surfaceactive compositions in the form of fine, non-coherent powders starting from dry or substantially dry surface-active substances which are secondary sulphuric acid alkyl ester salts, or mixtures thereof with inorganic salts, the particles of which substances display a tendency to stick together comprises grinding these substances in the presence of a substance added to them which in finely divided condition shows no or only little tendency to stick together.  The substance to be added may be alkali metal or ammonium sulphates, phosphates or chlorides, or talc, kaolin or bentonite, but anhydrous sodium sulphate powder is preferred.  In an example given, a dry powder containing 60 per cent of ester salt and 40 per cent of sodium sulphate, formed by atomization-drying of an aqueous secondary sodium alkyl sulphate solution, is ground with an equal quantity of sodium sulphate.  The Specification as open to inspection under Sect. 91 comprises also the use of the process with other surface-active substances such as primary sulphuric acid ester salts, alkyl sulphonates, alkyl aryl sulphonates and sulpho-succinic acid ester salts.  In an example, sodium salt of sulpho-succinic acid di-octyl ester is ground together with bentonite or talc.  This subject-matter does not appear in the Specification as accepted.