Patent GB-879873-A (GB)
Title: Stable aminoplast precondensation products and process for preparing them
IPC: C08G12/24
Filed: 1958-02-03
Abstract: Aminoplasts are formed in the presence of an N-sulphonic acid salt and a polyhydroxy compound at a pH between 7 and 8,5. Suitable aminoplast-formers are melamine, urea, dicyandiamide, guanylurea or ethylene diurea and formaldehyde, acetaldehyde, furfural, acrolein, glyoxal or benzaldehyde or mixtures thereof. These bodies may be reacted together alone and the product then reacted, with the sulphonate and, simultaneously or subsequently with the polyhydroxy compound.  Alternatively the sulphonate may be included in the initial reaction of the aminoplast formers and the product reacted with the polyhydroxy compound.  Suitable sulphonates are metal, especially alkali metal salts of melamine-N-sulphonic acid; benzamide-N-sulphonic acid; acetamide-N-sulphonic acid; hydrazine-N-sulphonic acid; or amidosulphonic acid.  Suitable salts can also be formed by reacting chlorsulphonic acid in pyridine with an aminoplast-former.  Suitable polyhydroxy compounds are glycol, diglycol, glycerine, trimethylol propane, 1,4-butanediol, sorbitol, glucose, glycerine-mono-benzyl ether, glycerine-monophenyl ether, triethanolamine, bis-[di-b -hydroxyethyl)-amino]-diethyl ether or the ether of triethanolamine having the formula: <FORM:0879873/IV (a)/1> The products are stable in neutral or alkaline solution, or in acid solution at room temperature.  Heated in neutral or acid medium above 100 DEG C. if desired in presence of a catalyst, e.g. an ammonium salt they lose sulpho groups and give water-insoluble products.  They are useful for treating furs, skins, leather, textiles or paper if desired together with other textile finishing agents.  They are also good dispersing agents for pigments, e.g. copper phthalocyanine, TiO2 or soot.  In examples condensation products are formed from sodium amidosulphonate, melamine and formaldehyde with (1) trimethylol propane, (2) glycerine, (3) sorbitol, (4) glycol, (5) 1, 4-butanediol, (7) triethanolamine (in this example the product was after-treated with dimethyl sulphate).  In Example (6) the condensate is formed from sodium amidosulphonate, 1, 4-butanediol-bis-urethane, formaldehyde and 1, 4-butane-diol.  In Example (8) the condensate was prepared from sodium amidosulphonate, urea, formaldehyde and glycol.ALSO:Modified aminoplasts containing sulpho groups (see Group IV(a)), stable in neutral or alkaline solution and in acidic textile treating baths at room temperature, may be used, if desired in conjunction with other known textile finishing agents, to treat textiles.  Heating above 100 DEG C. under acid or neutral conditions then drives off sulpho groups and leaves a waterresistant finish. The process may produce antishrinking, anti-felting, stiffening, embossing or similar effects.  The products are also good dispersing agents for pigments, e.g. copper phthalocyanine, TiO2 or soot, to produce printing pastes which, after heating, give water-resistant prints.  They may also be used for dyestuff fixing on furs, skins, leather or textiles.  In Example (4) a bath containing an aqueous condensate from sodium amido sulphonate, melamine, formaldehyde and glycol in admixture with polyvinyl acetate and ammonium nitrate is padded on to cotton fabric which is then dried and heated to give a water-resistant stiffening.  Alternatively the condensate solution may be mixed with ammonium caseinate, or glycollic acid, or ammonium sulphate and octadecyl ethylene urea, or a water-soluble cellulose ether before being used to treat textiles.  A dyestuff printing paste is prepared from the condensate with a press cake of copper phthalocyanine, ammonium nitrate and a kerosene emulsion as thickener.  In Example (7) a condensate from sodium amidosulphonate, melamine, formaldehyde and triethanolamine is after-treated with dimethyl sulphate, and the solution of the product is added to a bath of direct dyestuff, acidified with acetic or glycollic acid.  Fabric dyed in the bath and heated has increased resistance to water.