Patent GB-861451-A (GB)
Title: Optical brightening triazolyl stilbenes, their production and use
Filed: 1957-08-22
Abstract: The invention comprises triazolyl stilbenes of the general formula <FORM:0861451/IV (b)/1> and their alkali metal and ammonium salts and their manufacture by tetrazotizing 1 mol. of 4,31-diaminostilbene-2-sulphonic acid, coupling the tetrazo product with 2 mols. of the same or different aminonaphthalene sulphonic acids, viz. 1- or 2-aminonaphthalene sulphonic acids coupling in the 2- or 1-position respectively and free from any other substituents, and oxidizing the di-o-amino azo dyestuff obtained to form the desired 4,31-bis-[sulphonaphtho-(1,2)-triazolyl] stilbene-2-sulphonic acid or salt thereof.  The alkali metal and ammonium salts of the products are useful as optical brightening agents in treating textiles (see Group IV (c)) and in cleansing compositions (see Group III).  In examples: (1) 4,31-diaminostilbene-2-sulphonic acid is tetrazotized, then coupled with 2-amino-naphthalene-5-sulphonic acid or 1-amino-4-sulphonic acid and the resulting di-o-amino azo dyestuff is oxidized with ammoniacal copper sulphate or sodium hypochlorite and the product isolated as the tris-sodium salt; (2) 2-amino-naphthalene-6-sulphonic acid; and (3) 2-amino-naphthalene-7-sulphonic acid are used in like manner; (4) 4,31 - diamino stilbene-2-sulphonic acid is tetrazotized and coupled with one mol. of 2- aminonaphthalene-5-sulphonic acid and aminonaphthalene-5-sulphonic acid and then with one mol. of 2-amino-6-sulphonic acid or 2-amino-7-sulphonic acid and the diazo dye oxidized as above.  The 4,31-diamino stilbene-2-sulphonic acid is prepared by condensing m-nitrobenzaldehyde with 1-methyl-4-nitrobenzene-2-sulphonic acid phenyl ester, saponifying the product and then reducing the nitro groups of the resulting 4,31-dinitro stilbene-2-sulphonic acid.  Specification 683,895 is referred to.ALSO:Textile materials including cellulose and linear polyamide fibres, e.g. nylon and perlon, are optically brightened by means of the alkali metal or ammonium salts of triazolyl stillbene sulphonic acids of the general formula. <FORM:0861451/IV(c)/1> The brightening agents may be utilized for this purpose in washing or rinsing liquors, starch pastes, discharging and reserve printing pastes, soaps or synthetic detergents.  According to Examples, the trisodium salt of 4.31-bis-[(51-sulphonaphtho-11.21 : 4.5)-1. 2. 3-triazolyl-2] -stilbene-2-sulphonic acid is used (5) in an aqueous Glanber's salt bath for rinsing cotton poplin, (6) in an aqueous bath containing grain soap and soda for washing cotton goods and (7) in an aqueous formic acid dye bath for treating pale yellow nylon fabric. Di-#s-amino azo stilbene dyestuffs, which on oxidation yield the above-defined brightening agents (see Group IV (b), are prepared by coupling one mole of tetrazotized 4.31-diamino stilbene-2-sulphonic acid with two moles of the same or different amino-naphthalene sulphonic acids viz. 1- or 2-amino napthalene sulphonic acids coupling in the 2- or 1- position respectively and free from any other substituents, e.g. 2-amino naphthalene-5-, -6- or -7- sulphonic acid or 1- aminonaphthalene-4-sulphonic acid. Specification 683,895 is referred to.ALSO:Detergent compositions comprise, as optical brightening agents, the alkali metal and ammonium salts of triazolyl stilbene sulphonic acids of the general formula <FORM:0861451/III/1> In Example 6, a washing liquid comprises grain soap, soda and the trisodium salt of 4,31-bis-[(51 - sulphonaphtho - 11,21 : 4,5) - 1,2,3 - triazolyl - 2] - stilbene - 2 - sulphonic acid, Specification 683,895 is referred to.