GB941689A - Improvements in or relating to cellulosic textile materials - Google Patents

Abstract

The crease resistance of cellulosic textile materials, e.g yarns threads and woven, knitted or unwoven fabrics composed wholly or partially of natural cellulose such as cotton, regenerated cellulose or cellulose derivatives such as cellulose acetate is improved by treating the materials with a sensitiser which is an ethylenically-unsaturated organic compound, an aromatic compound or a primary, secondary or tertiary amine in a proportion sufficient to sensitise the cellulose to irradiation without causing any changes in its appearance or finish, subjecting it to ionising radiation able to penetrate the material without inducing substantial radioactivity therein, e.g. gamma radiation, X-rays and accelerated electron radiation, at a dosage less than 107 rad and then contacting it, preferably at a temperature above 40 DEG C., with a substance able to undergo graft reaction with substances having free radicals, with the exception of aldehydes or condensable substances as defined in Specification 930, 427, to effect grafting between the graftable substance and the cellulosic textile material. In a modification of the process the irradiation and grafting are carried out simultaneously by treating the material first with the sensitiser and then with the graftable substance and then irradiating. The sensitiser may be an aromatic hydrocarbon having 1-4 rings either condensed or uncondensed, an aliphatic compound having 4-20 carbon atoms in a chain and 1-3 isolated or conjugated double bonds or an aromatic saturated or unsaturated ketone, preferred sensitisers being 1,4-diphenyl benzene, pyrene and 1,4-diketo 2,3-dihydronaphthalene. Suitable sources of gamma radiation are Co60 and Cs137 and the accelerated electrons which preferably have an energy of 0.50-0.6 Mev may be generated by cascade, Vander Graaf or linear accelerators or radioactive sources such as Sr90 may be used. The graftable substances may be polymerizable monomeric compounds, e.g. acrylamide, acrylates, methacrylates, styrene, vinylacetate, vinyl chloride, vinylidene chloride, ethylene, tetrafluorethylene, butadiene, isoprene and divinyl sulphone, substances incapable of polymerization, e.g. alcohols, ketones, acetals, halogenated hydrocarbons, amines, esters, ethers and phenols, or fully polymerized compounds, e.g. polyethylene, polymethacrylates and polyvinyl chloride. The sensitisers and the graftable substances may be applied to the cellulosic materials in the form of a solution or dispersion in water or an organic solvent. Transparentised fine fabrics obtained by the treatment of cellulosic fabrics with sulphuric acid, cuprammonium solution or sodium zincate cellulose solution and fine cellulose fabrics composed or relatively high twist yarns, e.g. voiles and marquisettes, may be treated. Specification 895, 478 also is referred to.