Patent GB-181392-A (GB)
Title: Manufacture of cellulose derivatives
IPC: D06M13/13
Filed: 1922-06-12
Abstract: Cellulose ethers that are soluble in water or that swell in cold water water, are converted into products insoluble in water or in which the property of swelling is substantially reduced, by treatment with a reagent having the property of precipitating albumen, for instance, tannin or other natural or synthetic tanning agent, or trichloracetic acid, phosphotungstic acid, chrome or potash alum, or aluminium sulphate.  The treatment may be applied to the ethers in the crude state or to the articles prepared therefrom, such as films, artificial silk, coatings, dressings and sizings in textiles, paper, leather, &c., or plastic masses; and the treatment may be carried in aqueous solution, in which case the products are precipitated, or in organic solvents in which the ether and the conversion product are soluble, and in this case the resulting solution may be worked up directly into the desired article, or the products may be precipitated from the solution by dilution with water.  Suitable solvents for the water-insoluble products are,-acetic acid, benzolalcohol, chloroform, and chloroform-alcohol.  In examples, to a water solution of ethyl or methyl cellulose a solution of tannin is added, and the precipitate collected, washed, and dried or dissolved in acetic acid; alternatively, formalin may be added in addition to the tannin solution; a film or artificial silk made from a water solution of ethyl or methyl cellulose, or cloth or paper coated therewith, is immersed either in the finished condition or still wet, in a solution of tannin; an article made from an ethyl cellulose that swells in water at 16 DEG  C., is, after a previous swelling in water, treated with a solution of tannic acid or other tanning material, and the clear solution is either precipitated with water and the precipitate collected or dried, or the solution is worked up into a film or artificial silk or used as a coating or dressing.  The articles treated may contain other cellulose derivatives such as cellulose hydrate, nitrate and acetate, or other colloids such as albumen, fibroin, keratine, glue and gelatine, or softening or plastifying agents such as drying or non-drying oils, fats, balsams, phosphoric acid esters of phenols, high boiling point hydrocarbons, camphor, naphthalene and its derivatives, phenol ethers, other high boiling point ethers, or esters, glycerine, sugars, turkey red oil, soaps, &c. Specifications 12854/12, 181,393 and 181,395 are referred to.ALSO:Sizes and finishes are prepared with cellulose ethers that have been rendered insoluble in water, or in which the property of swelling therein is substantially reduced, by treatment with a reagent having the property of precipitating albumen, for instance, tannin or other natural or synthetic tanning agent, or trichloracetic acid, phosphotungstic acid, chrome or potash alum, or aluminium sulphate.  The treatment may be effected in aqueous solution, in which case the products are precipitated, or in organic solvents in which the ether and the conversion product are soluble, and in this case the resulting solution may be worked up directly into the desired article, or the products may be precipitated from the solution by dilution with water.  Suitable solvents for the water-insoluble products are: acetic acid, benzol-alcohol, chloroform, and chloroform-alcohol.  The finishes &c. may contain other cellulose derivatives such as cellulose hydrate, nitrate and acetate, or other colloids such as albumen, fibroin, keratin, glue, and gelatine, or softening or plastifying agents such as drying or non-drying oils, fats, balsams, phosphoric acid, esters of phenols, high boiling point hydrocarbons, camphor, naphthalene and its derivatives, phenol ethers, other high boiling point ethers or esters, glycerine, sugars, Turkey-red oil, soaps, &c.  Specifications 12854/12, 181,393 and 181,395 are referred to.