GB466490A - Improvements in or relating to thermoplastic compositions containing an organic derivative of cellulose, and articles coated or impregnated therewith - Google Patents

Abstract

Textile fabric, felt, paper or other fibrous material is coated or impregnated with a thermoplastic composition having a basis of an organic derivative of cellulose and a plasticizer therefor, and containing a condensation product of an aldehyde with an oxidized vegetable oil. The production of such condensation products is described in Specification 466,421. The composition is preferably employed as a film, foil or sheet-like web formed by pressing it in the form of a powder. Woven, netted, knotted or knitted fabrics, wire mesh, hair felts, cotton felts, paper, cardboard, asbestos fabrics may be coated or impregnated with the composition to produce materials which may be used in place of leather, oil-cloth or linoleum or may be veneered on iron or wood and used for covering floors, furniture, automobile bodies, walls, counters or containers. The composition may contain resins, halogenated rubber, filling materials and/or pigments such as clay, metal oxides, salts, dyes, or lakes. Suitable plasticizers are dibutyl phthalate, diethyl phthalate, dibutyl tartrate, monethyl xylene sulphonamide, monomethyl paratoluene sulphonamide p and diphenyl phosphate. The oxidized vegetable oil is preferably castor oil, but may be oxidized olive, soya bean or linseed oil. The aldehyde used may be formaldehyde, acetaldehyde, paraldehyde, metaldehyde or crotonic aldehyde, the proportion of aldehyde to oil being about 30 parts by weight of aldehyde to 100 parts by weight of oil. The composition may be formed into a sheet in any suitable manner and applied to the base material which may be preheated. Preferably the composition is applied as a sheet like web formed by heating and pressing a layer of powder until the particles adhere. Some of the particles may still however retain their particular form. The coated assembly is then pressed at elevated temperatures. The powder may be formed by grinding and dispersing the ingredients in a liquid which is non-solvent for the cellulose derivative, e.g. in a colloid mill between discs having opposite abrasive surfaces and opposite rotating movements. The composition may also be formed to a film by casting a solution thereof and applied to the base material in this form. Formation of sheets and application to the base may constitute a continuous operation. The degree of penetration of the composition into the base is governed by the amount of pressure employed. After coating or impregnation, the material may be embossed, e.g. in imitation of leather, e.g. skiver, pigskin, morocco, or in flower, check or striped designs. In an example cellulose acetate, triphenyl phosphate, ethyl paratoluene sulphonamide, diethyl phthalate, chrome yellow, and formaldehyde oxidized castor oil condensation product, are suspended in water and subjected to dispensing and grinding. The water is evaporated and the dry powder passed through a calender and formed to a sheet like web of about \ba5/100\be" thick. The web is applied to a cotton duck fabric under heat and pressure sufficient to cause partial permeation of the composition into the fabric. The composite material is then passed over a cold roll and then embossed by passage between nip rollers, one having a design and being heated. The Specification as open to inspection under Sect. 91, is not limited to the use of an oxidized vegetable oil for the manufacture of the condensation product.