Patent GB-661277-A (GB)
Title: Process of producing insoluble layers on carriers from carboxylic acids of high molecular weight
IPC: D06M15/09
Filed: 1948-05-29
Abstract: A solution of a ferrous salt and a salt, which dissolves or swells in water, of a cellulose derivative containing one or more carboxyl groups and of which the ferrous salts are soluble and the ferric salts insoluble, is employed for impregnating or coating textiles, or as an adhesive, or as a binder for pigments or fillers, and the composition is subsequently rendered insoluble by oxidation. Oxidation may be effected by exposure to the air or to ultra-violet or infra-red light, or by the addition of an oxidizing-agent such as hydrogen peroxide, benzoyl peroxide or perbenzoic acid, or a siccative such as cobalt or manganese naphthenate or linoleate.  To retard oxidation, an anti-oxidant such as sodium hydrosulphite may be added.  The ferrous salt may be ferrous sulphate or ferrous ammonium sulphate.  The cellulose derivative may be a cellulose ether or cellulose ester carboxylic acid.  Other natural or synthetic compounds containing free carboxyl groups may be included, e.g. abietinic acid, fatty acids of high molecular weight, polymethacrylic acid, or shellac.  To increase water-resistance, a small amount of an artificial resin, if desired in the precondensation state, may be included, for example, a urea, melamine or phenol resin.  According to an example, a solution of ferrous sulphate is added to a solution of cellulose glycollate and a small amount of sodium hydrosulphite is added.  Specifications 494,927, 601,374, [Group IV (b)], 632,789, [Group V], and 661,278, [Group IV (b)], are referred to.ALSO:A process for forming an insoluble layer on a surface comprises treating the surface with a solution of a ferrous salt and a salt, which dissolves or swells in water, of an organic compound of high molecular weight containing one or more carboxyl groups and of which the ferrous salts are soluble and the ferric salts insoluble, and subsequently oxidizing the ferous salt.  Oxidation may be effected by exposure to the air or to ultra-violet or infra-red light, or by the addition of an oxidizing-agent such as hydrogen peroxide, benzoyl peroxide or perbenzoic acid, or a siccative such as cobalt or manganese naphthenate or linoleate. To retard oxidation, an anti-oxidant such as sodium hydrosulphite may be added.  The ferrous salt may be ferrous sulphate or ferrous ammonium sulphate.  The organic compound may be a starch-ether and/or starch-ester carboxylic acid containing in the ether and/or ester group one or more free carboxyl groups or alginic acid. Other natural or synthetic compounds containing free carboxyl groups may be included, e.g. abietinic acid, fatty acids of high molecular weight, polymethacrylic acid, or shellac.  To increase water-resistance, a small amount of an artificial resin, if desired in the precondensation state, may be included, for example a urea, melamine or phenol resin.  According to examples: (a) the sodium salt of starch-ether carboxylic acid, prepared by adding sodium monochloracetate to a mixture of starch and caustic soda in water as described in Specification 601,374, is dissolved in water and mixed, after acidifying with phosphoric acid or adding sodium hydrosulphite, with ferrous sulphate; (b) ferrous sulphate solution is added to a cold, slightly alkaline solution of sodium alginate.  Specifications 494,927, 632,789, [Group V], and 661,278, [Group IV (b)], are referred to.