Patent GB-481099-A (GB)
Title: Process for rendering cellulosic material water-repellent
IPC: D06M15/423
Filed: 1936-08-26
Abstract: Cellulosic materials such as cotton, jute or linen fabrics, paper, regenerated cellulose, cellulose esters and ethers, e.g. viscose and cellulose acetate are rendered water repellent by treatment with an aldehyde and an amide of a higher fatty acid having at least 10 carbon atoms, or with a pre-formed reaction product of such an amide compound with an aldehyde, and subjecting the treated material, preferably in the presence of an acid substance as catalyst, to the action of dry heat.  The treatment may be carried out in the presence of a wax.  Example 3 described treating mercerized cotton fabric with an aqueous dispersion made by milling in a ball mill stearohydroxy-ethylamide water and a naphthalene formaldehyde sulphuric acid condensation product prepared as described in Specification 224,077, [Class 1 (i)], and adding sodium dihydrogen phosphate, drying at 30-40 DEG  C. and then heating at 120 DEG  C. Reference has been directed by the Comptroller to Specification 463,300.ALSO:Cellulosic materials such as cotton, jute, or linen fabrics, paper, regenerated cellulose, cellulose esters and ethers, e.g. viscose and cellulose acetate are rendered water repellent by treatment with an aldehyde and an amide of a higher fatty acid having at least 10 carbon atoms, or with a pre-formed reaction product of such an amido compound with an aldehyde, and subjecting the treated material, preferably in the presence of an acid substance as catalyst, to the action of dry heat.  The treatment may be carried out in the presence of a wax.  Suitable acid amides are oleyl amide, stearamide, lauramide, lauryl benzamide, stearomethylamide and stearanilide.  The reaction product may be stearohydroxymethylamide prepared as described in Specification 475,170.  The reagents may be applied simultaneously or successively as solutions in organic solvents such as acetone or as aqueous dispersions.  The aldehyde, e.g. formaldehyde or paraformaldehyde may be applied in aqueous solution or as vapour. Suitable acid catalysts are sodium dihydrogen tartrate, tartaric acid and lactic acid; they may be applied before, together with, or after the treatment reagents.  Examples describe (1) treating cotton fabric in an acetone solution of stearamide, drying and immersing in aqueous formaldehyde containing sodium dihydrogen phosphate, drying at 30 DEG  C. and heating at 130 DEG C.; (2) wetting cotton fabric with an aqueous solution of sodium dihydrogen phosphate, drying, treating with an ethanol or acetone solution of stearohydroxymethylamide or oleyl hydroxymethylamide at 40 DEG  C., drying at 30-40 DEG  C. and heating at 120 DEG  C. Alternatively, the catalyst may be phosphoric acid added to the solution of the amide; (3) treating mercerized cotton fabric with an aqueous dispersion made by milling in a ball mill stearohydroxyethylamide, water and a naphthalene formaldehyde sulphuric acid condensation product prepared as described in Specification 224,077, [Class 2 (iii)], and adding sodium dihydrogen phosphate, drying at 30-40 DEG  C. and then heating at 120 DEG  C.; (4) impregnating cotton fabric in a warm solution containing paraffin wax dissolved in benzene and methylol stearamide and phosphoric acid dissolved in methylated spirits, drying at 35 DEG  C. and then heating at 130 DEG  C.  French Specification 797,049 also is referred to.  Reference has been directed by the Comptroller to Specification 463,300.