Sulphone-compounds having the general formula R1.SO2.R2.CONRR3 wherein R and R3 are hydrogen or a hydrocarbon radical, R1 is a hydrocarbon radical and R2 is a hydrocarbon radical linking the sulphone group to the carbonyl carbon atom by a chain of not more than 4 carbon atoms, R1 and/or R3 containing a chain of 8 to 18 carbon atoms, may be prepared by oxidizing, for example with nitric acid, the corresponding thioether substituted carboxylic acids and reacting the resulting sulphone-carboxylic acid with an amine. Thus betamethyl thio propionic acid is oxidized to betamethylsulphonyl propionic acid which is then condensed with myristylamine yielding N-myristyl beta (methyl sulphonyl) propionamide. N - lauryl - 2(methyl sulphonyl) - acetamide, N - methyl N - palmityl - 2(methyl sulphonyl)-acetamide and N - methyl - 3(lauryl sulphonyl)-propionamide are given as further examples. Sulphones having the general formula R1.CO. N(R)(R2.SO2.R3) wherein R1 and R3 represent hydrocarbon radicals, at least one of which contains a chain of 8 to 18 carbon atoms, R is hydrogen or a hydrocarbon radical and R2 is a hydrocarbon radical linking the sulphone group to the nitrogen atom by a chain of not more than 4 carbon atoms may be prepared by reacting an olefinic amine with a mercaptan, oxidizing the resulting thio amine to the sulphoneamine and acylating with an appropriate carboxy acid or by reacting a hydroxy sulphide such as 2-methyl mercapto ethanol with ammonia, acylating the resulting thio amine and then oxidizing with nitric acid or hydrogen peroxide to form the sulphone-amide. Specified compounds so obtainable are N(2-methyl sulphonyl)-ethyl lauramide, N(3-methyl sulphonyl)-propyl myristamide, N(undecyl sulphonyl)-methyl acetamide and N-2(methyl sulphonyl)-ethyl N-methyl capramide. The compounds are used as additives in surface-active compositions (see Group IV (c)).ALSO:Surface-active compositions yielding aqueous solutions having improved foaming properties comprise a water-soluble surface-active salt of an organic acid having a hydrotropic group comprising a hydrocarbon chain of at least 8 carbon atoms and a sulphone free from sulphonic acid groups and containing at least one hydrotropic radical of from 8 to 18 carbon atoms, at least one imidocarbonyl group - NR.CO-, wherein R represents a hydrogen atom or a hydrocarbon radical, and at least one sulphone-containing group CSO2C the sulphur atom of which is linked through not more than four intervening carbon atoms either to the nitrogen atom or to the carbonyl carbon atom of the imido-carbonyl group. Suitable sulphone compounds include those having the general formula R1.SO2.R2.CO N RR3 wherein R and R3 represent hydrogen or a hydrocarbon radical, R1 is a hydrocarbon radical and R2 is a hydrocarbon radical linking the sulphone group to the carbonyl carbon atom by a chain of not more than 4 carbon atoms, at least one of the radicals R1 and R3 being a hydrocarbon radical containing a chain of 8 to 18 carbon atoms; in addition R1 and R2, R1 and R or R and R2 may be hydrocarbon radicals linked together to form a ring. Examples given of these sulphones include N-myristyl beta-(methyl sulphonyl) propionamide, N-methyl-N-palmityl-2 (methyl sulphonyl) acetamide, 3-decyl-5-sulpholanyl-carboxamide, N-lauryl-2-sulpholanyl-carboxamide, 2-(1-methyl hexadecyl)-5-ketothiamorpholine-1-dioxide, 1-(octadecyl sulphonyl-acetyl)-3-methyl urea and 1-(3-sulpholanyl carboxyl)-3-hexadecyl urea. Another suitable class of sulphones has the general formula R1.CO.N(R) (R2.SO2.R3) wherein R1 and R3 are hydrocarbon radicals, at least one of which contains a chain of 8-18 carbon atoms, R is hydrogen or a hydrocarbon radical and R2 is a hydrocarbon radical linking the sulphone group to the nitrogen atom of the imido-carbonyl group by a chain of not more than 4 carbon atoms; in addition R may be linked to R2 or R3 or R1 to R2 or R3. Examples given of these include N-(2-methylsulphonyl) ethyl lauramide, N-(undecyl sulphonyl) methyl acetamide, 4-(methyl sulphonyl)-1-lauroyl-piperidide, 4-hendecanoyl) thiamorpholine-1-dioxide, delta-(lauryl sulphonyl) valerolactam, N - (3-sulpholanyl) lauramide, N-(4-thianyl-1-dioxide) palmitamide and others described in U.S.A. Specification 2,435,071. Amides of sulphone-substituted amines and sulphone-substituted carboxylic acids may also be used such as N-octadecyl sulphonylmethyl methyl sulphonyl acetamide and N-(3-sulpholanyl) hexadecyl sulphonyl acetamide. The sulphones are normally used in amounts of between 1 and 50 per cent of the weight of surface-active material. The surface-active materials specified include the alkali-metal, ammonium and amine salts of carboxylic acids, sulphonic acids, organic phosphorus-containing acids and sulphuric acid esters, each having a hydrophobic group as stated above. Reference is made to the salts of alkyl aryl sulphonic acids such as those obtained by alkylating a benzene hydrocarbon with a long chain alkylating agent e.g. an olefinic, olefine polymer or an alkyl halide and sulphonating the alkylate; salts of sulphuric acid esters as obtained by reacting sulphuric acid with olefines such as cracked paraffin wax olefines and alcohols such as those obtained by hydrogenation of fatty oils; salts of such sulphonates and sulphates as also contain halogen, ether-oxygen, carbonyl or carboxyl substituents, for example, sulphuric acid esters of hydroxy ethers of higher molecular alcohols such as mono- or di-ethylene glycol mono-myristyl ether, carboxylic acid esters of hydroxy-alkyl acid sulphates such as glycerine mono-laurate mono-sodium sulphate and ethylene glycol mono-stearate sodium sulphate, sulphated carboxylic acid alkylolamides such as coconut oil fatty acid ethanolamide sodium sulphate, ethers of long chain alcohols with lower molecular hydroxysulphonic acids such as the dodecyl ether of isethionic acid sodium salt, sulphocarboxylic acid esters such as salts of sulphoacetic acid esters of C8 to C20 alcohols, and the reaction products of higher fatty acids with hydroxy sulphonic acids and amino sulphonic acids such as isethionic acid and N-methyl taurine. The sulphones may also be used with the corresponding esters of phosphorus acids including phosphates and phosphites and with fatty acid soaps. The improved compositions may also comprise such additives as bleaching agents, perfumes, dyes, trisodium phosphate, tetrasodium pyrophosphate, sodium carbonate, sodium silicate and carboxymethyl cellulose. Examples describe compositions comprising soap, sodium dodecyl benzene sulphonate derived from propylene tetramer, "Teepol" (Registered Trade Mark), sodium 2-n-tetradecane, sulphonate, magnesium dodecyl benzene sulphonate or sodium dodecyl toluene sulphonate, N-(3-sulpholanyl) lauramide or myristamide, N-(2-methyl sulphonylethyl) capramide, N-(2-dodecylsulphonylethyl) acetamide or 3-methylsulphonyl propionic laurylamide and additives selected from sodium tripolyphosphate, sodium sulphate, magnesium sulphate, sodium pyro phosphate and carboxymethyl cellulose.ALSO:Washing and cleansing compositions yielding aqueous solutions having improved foaming properties comprise (1) a water-soluble surfaceactive salt of an organic acid having a hydrophobic group comprising a hydrocarbon chain of at least 8 carbon atoms, and (2) a sulphone free from sulphonic acid groups and containing at least one hydrophobic radical of from 8 to 18 carbon atoms, at least one imido carbonyl group -NR.CO-, wherein R represents a hydrogen atom or a hydrocarbon radical, and at least one sulphone-containing group -C.SO2C-, the sulphur atom of which is linked through not more than four intervening carbon atoms either to the nitrogen atom or to the carbonyl carbon atom of the imido-carbonyl group. Suitable sulphones include those having the general formula R1. SO2. R2 CO NRR3 wherein R and R3 represent hydrogen or a hydrocarbon radical, R1 is a hydrocarbon radical and R2 represents a hydrocarbon radical linking the sulphone group to the carbonyl carbon atom by a chain of not more than 4 carbon atoms, at least one of the radicals R1 and R3 being a hydrocarbon radical containing a chain of 8 to 18 carbon atoms; in addition R1 and R2, R1 and R or R and R3\h may be hydrocarbon radicals linked together to form a ring. Examples given of these sulphones include N-myristyl-beta-(methyl sulphonyl)propionamide, N-methyl-N-palmityl -2(methylsulphonyl)acetamide, 3 - decyl - 5 - sulpholanyl-carboxamide, N-lauryl-2-sulpholanyl-carboxamide, 2-(1-methylhexadecyl)-5-ketothiamorpholine-1-dioxide, 1-(octadecylsulphonyl-acetyl)-3-methyl urea and 1-(3-sulpholanylcarboxyl)-3-hexadecyl urea. Another suitable class of sulphones has the general formula R1. CO.N (R) (R2. SO2. R3), wherein R1 and R3 represent hydrocarbon radicals, at least one of which contains a chain of 8 to 18 carbon atoms, R is hydrogen or a hydrocarbon radical and R2 represents a hydrocarbon radical linking the sulphone group to the nitrogen atom of the imido-carbonyl group by a chain of not more than 4 carbon atoms; in addition R may be linked to R2 or R3 or R1 to R2 or R3. Examples given of these include N-(2-lethyl sulphonyl, ethyl lauramide, N-(undecylsulphonyl) methyl acetamide, 4-(methylsulphonyl)-1-lauroyl-piperidide, 4-hen-decanoylthiamorpholine-1-dioxide, delta-(laurylsulphonyl)valerolactam. N-(3-sulpholanyllauramide, N-(4-thianyl-1-dioxide) palmitamide and others described in U.S.A. Specification 2,435,071. Amides of sulphone-substituted amines and sulphone-substituted carboxylic acids may also be used, such as N- octadecyl sulphonylmethyl methylsulphonyl acetamide and N-(3-sulpholanyl) hexadecyl sulphonyl acetamide. The sulphones are normally used in amounts of between 1 and 50 per cent. of the weight of surface-active material. The surface-active materials include the alkali metal, ammonium and amine salts of carboxy