Patent GB-181393-A (GB)
Title: Manufacture of cellulose ethers
IPC: C08B11/02
Filed: 1922-06-12
Abstract: Ethyl ethers of cellulose, insoluble in water at 16 DEG  C. but which swell or dissolve in water at lower temperatures, are prepared from cellulose or an alkali-insoluble cellulose conversion products such as cellulose hydrate, hydrocellulose and oxycellulose, by treatment with an alkylating-agent in the presence of 0.48-2.5 parts of water and 0.6-8 parts of caustic alkali to one part of cellulose, the amount of alkali in any case exceeding the weight of water present. The caustic alkali may be introduced as a solution or in the solid state, or partly in the solid state and partly as a saturated solution; and the treatments with alkali and alkylating-agent may be carried out in succession or at the same time.  As ethylating-agents, diethyl sulphate or ethyl halides may be employed.  The temperature of the reaction may vary between 80 and 180 DEG  C.  By reason of their property of swelling or dissolving in cold water, the ethers may be used for the manufacture of articles that have to be incorporated with substances soluble in water, for example, dyes; and they are also suitable for the manufacture of artificial silk, hair, &c., films, photographic lacquers, emulsions, &c., coatings, dressings, fillings and finishings for textiles, paper, leather, &c., sizes, printing agents, thickening-agents for printing-compositions, agents for fixing pigments, adhesives, cements, artificial leather and book cloth; and for these uses, the ethers may be combined with other water-soluble or water-insoluble cellulose derivatives or colloids and may be mixed with binding-, thickening- and softening-agents, and plastifiers. The Specification contains a number of examples, the products of which show slight differences in their behaviour towards cold water, but which are soluble in a wide range of organic solvents. Specifications 12854/12, 6035/13 and 163,018 are referred to.  The Specification as open to inspection under Sect. 91 (3) (a) includes the production of alkyl ethers generally, and contains two additional examples, in one of which dimethyl sulphate is the alkylating-agent, and in the other ethyl chloride; and it fixes the lower limit of the proportion of water at 0.3 parts to one part of cellulose.  This subject-matter does not appear in the Specification as accepted.ALSO:Ethyl ethers of cellulose which are insoluble in water at 16 DEG  C. but which swell or dissolve in water at lower temperatures and are prepared by treating cellulose or its conversion products with limited amounts of water and caustic alkali, are used in the preparation of dressings, fillings and finishings for textiles, paper, leather, &c., sizes, adhesives and cements.  For these uses the ethers may be combined with other cellulose derivatives or colloids, and may be mixed with braiding, thickening and softening agents, and with plastifiers.  The Specification as open to inspection under Sect. 91 (3) (a) includes the use of alkyl ethers in general and refers also to methyl ethers of cellulose.  This subject-matter does not appear in the Specification as accepted.ALSO:Ethyl ethers of cellulose which are insoluble in water at 16 DEG  C. but which dissolve or swell therein at lower temperatures, and are prepared by treating cellulose or an alkali-insoluble cellulose conversion product with an ethylating-agent in the presence of limited amounts of water and alkali, are used in the preparation of printing-agents as thickening-agents for printing-compositions, &c.  For these uses the ethers may be combined with other cellulose derivatives and with other colloids, and may be mixed with binding, thickening and softening agents, and with plastifiers.  The Specification, as open to inspection under Sect. 91 (3) (a) includes the use of alkyl ethers in general and refers also to the use of methyl ethers of cellulose. This subject-matter does not appear in the Specification as accepted.