GB386328A - Preparation of compositions containing synthetic resins and soluble alginates - Google Patents

Abstract

Mixtures of water-insoluble urea or thiourea formaldehyde condensation products free from strong acids with water-soluble salts of alginic acid such as sodium, potassium, ammonium or magnesium alginate or double alginates of metals and ammonia yield compositions capable of forming stable solutions and non-crazing films. The compounds may be mixed dry or in aqueous solution and in the latter case they may be carefully dried. The condensation product is preferably one containing excess of the basic component, i.e. urea or thiourea. Accelerators which do not coagulate or precipitate the algin as acid or salt may be added to the mixture. Organic acids, such as acetic, tannic, formic, benzoic, butyric or succinic acids ; boracic or carbolic acid ; potassium hydrogen sulphate ; acidic salts of magnesium or manganese such as sulphates or chlorides or salts of metals of lower atomic weight than that of magnesium may be used as accelerators. In examples, (1) a resin syrup prepared by condensing urea with formaldehyde is mixed with a solution of sodium alginate and, if desired, neutralized with an acid or acid salt such as potassium acid sulphate when required for use. Solutions thus prepared may be used as varnishes or paint vehicles with or without inert ingredients such as pigments, fibrous or other fillers, accelerators being used at the time of use. (2) The liquid composition of claim 1 may be dried to yield a readily water soluble powder which may be mixed with a dry accelerator, colours or fillers. A suitable filler is a soluble alkaline silicate. The product may be used as a size for fabrics, a wood or fibre impregnation agent, a stain or distemper for a plaster face or a solid water paint.ALSO:Mixtures of water-soluble urea- or thiourea-formaldehyde condensation products free from strong acids and water-soluble salts of alginic acid such as sodium, potassium, ammonium and magnesium, alginates or double alginates of metals with ammonia yield compositions capable of forming, with or without the addition of accelerators which do not coagulate or precipitate alginic acid, stable solutions which may be used as distempers or paint vehicles. Suitable accelerators are organic acids such as acetic, tannic, formic, benzoic, butyric or succinic acids; boracic or carbolic acid; potassium hydrogen sulphate; acidic salts of magnesium or manganese such as sulphates or chlorides; salts of metals of lower atomic weight than manganese. A suitable filler is a soluble alkaline silicate.ALSO:Mixtures of water-soluble urea- or thioureaformaldehyde condensation products free from strong acids and water-soluble salts of alginic acid such as potassium, ammonium, sodium or magnesium alginates or double alginates of metals and ammonia yield compositions capable of yielding, with or without the addition of accelerators which do not precipitate or coagulate alginic acid, a sizing agent for fabrics.