Patent GB-709557-A (GB)
Title: Improvements in or relating to a method of washing
IPC: C11D10/04
Filed: 1950-04-25
Abstract: Sulphated amides of the formula R-CO-NR1-CH2-CH2-O-SO3X  and derivatives substituted by alkyl in the ethylene group are made by (1) condensing NHR1-CH2-CH2OH with RCOOH or ester, treating the product with sulphuric or chlorsulphonic acid and neutralizing, or (2) forming the sodium salt of the sulphated alkanolamine and condensing with the acid chloride.  R is a straight or branched saturated or unsaturated aliphatic radical which may contain cyclic substituents and inorganic substituents such as hydroxyl or halogen; it has 5-17 carbon atoms in all; R1 is hydrogen or C1-C3 alkyl; X is an alkali metal, ammonium or substituted ammonium, or other cation which does not precipitate soap.  When R is unsaturated, sulphation may occur here also and in either case sulphonation may take place as well.  In method (1) the ester used may be methyl or ethyl, or may be a glyceride in which case the glycerine produced is washed out with brine.  The following products are mentioned:-sodium salt of sulphated coconut oil fatty acid ethanolamide, sodium salt of sulphated palm kernel fatty acid ethanolamide, sodium salt of sulphated sperm oil fatty acid ethanolamide and sodium salt of sulphated oleic acid ethanolamide.  Isopropanolamides are mentioned, and the neutralizing cation may be triethanolammonium.ALSO:Yarns and fabrics are treated first with an emulsion of a soap-forming fatty acid containing a soap-compatible sulphated amide of the formula R-CO-NR1-CH2-CH2-O-SO3 X (or derivative alkyl-substituted in the ethylene group), and then with an alkali to generate soap in situ. Alternatively the material is treated with a mixture of soap and the sulphated amide, acidified to deposit free acid, and alkali added as before.  The cleansing operation is completed by rinsing with warm water.  In the formula R is a straight or branched saturated or unsaturated aliphatic radical which may contain cyclic substituents and inorganic substituents such as halogen, hydroxyl or sulphate groups; it has 5-17 carbon atoms in all; R1 is hydrogen or C1-C3 alkyl; X is an alkali metal, ammonium or substituted ammonium, or other cation which does not precipitate soap; there may be sulphonate as well as sulphate groups present. Mixtures of sulphated amides and/or of fatty acids may be used. The group R is preferably the same as or closely related to the corresponding group of the fatty acid used.  As manufactured the sulphated amide may contain electrolyte (e.g. sodium or potassium sulphate) up to 200 per cent; when using a concentrated emulsion as stock solution this amount is preferably reduced to below 50 per cent (see below).  The sulphated amide may be used in amounts of 2 per cent to 300 per cent of the fatty acid, preferably 10-50 per cent.  The alkali used for soap-formation may be sodium carbonate or bicarbonate or a mixture of the two, sodium metasilicate or ammonia.  Preferably an excess is used over that needed to neutralize the acid and the hardness-producing ions in the water.  Thus in washing cotton goods 1000 per cent (based on soap formed) of sodium carbonate may be present.  There may also be added builders such as sodium silicate, orthophosphate, pyrophosphate or tripolyphosphate, sequestering agents, oxygenating agents (e.g. sodium percarbonate or perborate), suspending agents such as carboxymethylcellulose or partially hydrolysed polymethyl methacrylate, non-ionic surface active agents, e.g. polyglycol ethers of higher alcohols or of cholesterol or unsulphonated amides such as oleic acid ethanolamide, or other anionic detergents, e.g. sulphated fatty alcohols such as those from sperm oil.  Preferably the emulsion is prepared in concentrated form as a stock solution and diluted before use.  Such concentrated emulsion may contain 10-90 per cent (e.g. 20-70) of fatty acid, the ingredients being mixed 10 DEG C. above the melting point of the acid (but not below 55 DEG C.). Some (e.g. 10-30 per cent) of the acid may be neutralised with alkali to yield an emulsion of the desired consistency.  On heating the mixture of fatty acid and sulphated amide to 70 DEG C. the aqueous layer containing electrolytes separates and is run off; this improves the stability of the emulsion.  The emulsion may contain the additives mentioned above and also thickeners or stabilizers such as gelatine, sodium alginate or polyvinyl alcohol.  In examples, (1) an emulsion is made from palm oil fatty acids, the sodium salt of sulphated coconut oil fatty acid ethanolamide and sodium sulphate; soiled white cotton articles are introduced into the diluted emulsion at 35 DEG C. and excess of soda ash added, followed by further warm water, and the mixture boiled; the goods are then removed and rinsed; (2) an emulsion is prepared of the fatty acids and sulphated amide of (1) and caustic soda (to neutralize part of the acid); soiled goods are introduced into the diluted emulsion and final neutralization effected by adding soda ash, sodium metasilicate and carboxymethyl-cellulose; the goods are washed as in (1); (3) an emulsion similar to that of (2) is made from the sodium salt of sulphated palm kernel fatty acid ethanolamide, sodium polyphosphate being added; it can be used as in (1) or (2); (4) sperm oil is condensed with ethanolamine, sulphated and neutralized giving a mixture of sulphated alcohols and ethanolamides; this is mixed with caustic soda and olein (M.P. 30 DEG C.); the emulsion is diluted and used to wash soiled white blankets by addition of sodium carbonate/bicarbonate mixture; (5) as in (4) with the addition of an ethylene oxide cholesterol condensation product; (6) soiled cotton goods are introduced into a solution of soap and sulphated oleic acid ethanolamide and free fatty acid is liberated with disodium dihydrogen pyrophosphate; the soap is reformed with sodium metasilicate, and the goods are finally rinsed.ALSO:Cleansing compositions for yarns and fabrics comprise an emulsion of a soap-forming fatty acid containing a soap-compatible sulphated amide of the formula R-CO-NR1-CH2-CH2-O-SO3X (or derivative alkyl-substituted in the ethylene group); the goods are treated with this emulsion and then with an alkali to generate soap in situ. Alternately the goods are impregnated with a mixture of soap and the sulphated amide, acidified to deposit free acid, and alkali added as before.  In the formula R is a straight or branched saturated or unsaturated aliphatic radical which may contain cyclic substituents and inorganic substituents such as halogen, hydroxyl or sulphate groups; it has 5-17 carbon atoms in all; R1 is hydrogen or C1-C3 alkyl; X is an alkali metal, ammonium or substituted ammonium, or other cation which does not precipitate soap; there may be sulphonate as well as sulphate groups present.  Mixtures of sulphated amides and/or of fatty acids may be used.  The group R is preferably the same as or closely related to the corresponding group of the fatty acid used.  As manufactured the sulphated amide may contain electrolyte (e.g. sodium or posassium sulphate) up to 200 per cent.; when using a concentrated emulsion as stock solution this amount is preferably reduced to below 50 per cent. (see below).  The sulphated amide may be used in amounts of 2 per cent. to 300 per cent. of the fatty acid, preferably 10-50 per cent.  The alkali used for soap formation may be sodium carbonate or bicarbonate or a mixture of the two, sodium metasilicate or ammonia.  Preferably an excess is used over that needed to neutralise the acid and the hardness-producing ions in the water.  Thus in washing cotton goods 1,000 per cent. (based on soap formed) of sodium carbonate may be present.  There may also be added builders such as sodium silicate, orthophosphate, pyrophosphate or tripolyphosphate, sequestering agents, oxygenating agents (e.g. sodium perborate or percarbonate), suspending agents such as carbonymethyl-cellulose or partially hydrolysed polymethyl methacrylate, non-ionic surface active agents, e.g. polygycol ethers of higher alcohols or of cholesterol or unsulphonated amides such as oleic acid ethanolamide, or other anionic detergents, e.g. sulphated fatty alcohols such as those from sperm oil.  Preferably the emulsion is prepared in concentrated form as a stock solution and diluted before use.  Such concentrated emulsion may contain 10-90 per cent. (e.g. 20-70) of fatty acid, the ingredients being mixed 10 DEG C. above the melting point of the acid (but not below 55 DEG C.). Some (e.g. 10-30 per cent.) of the acid may be neutralised with alkali to yield an emulsion of the desired consistency.  On heating the mixture of fatty acid and sulphated amide to 70 DEG C. the equeous layer containing electrolytes separates and is run off; this improves the stability of the emulsion.  The emulsion may contain additives mentioned above and also thickeners or stabilisers such as gelatine, sodium alginate or polyvinyl alcohol.  Examples describe the following compositions: (1) palm oil fatty acids, sodium salt of sulphated coconut oil fatty acid ethanolamide and sodium sulphate, made alkaline on the fibre; (2) emulsions of (1) partly neutralised with caustic soda; final neutralisation is effected on the fibre with soda ash, sodium metasilicate and carboxymethyl-cellulose; (3) fatty acids of (1) with the sodium salt of sulphated palm kernel fatty acid ethanolamide and sodium polyphosphate, used as in (1) or (2); (4) emulsion made from olein (M.P. 30 DEG C.), caustic soda and the mixture of sulphated alcohols and ethanolamides obtained by condensing sperm oil with ethanolamine and sulphating; neutralisation is effected on the fibre with sodium carbonate/bicarbonate mixture; (5) as in (4) with the addition of an ethylene oxide cholesterol condensation product; (6) mixture of soap and, sulphated oleic acid ethanolamide; free fatty acid is liberated on the fibre with disodium dihydrogen pyrophosphate and soap