Patent GB-449984-A (GB)
Title: Improvements in or relating to the manufacture of articles comprising cellulose derivatives
IPC: B44C1/14
Filed: 1935-07-24
Abstract: A preformed cellulose derivative sheet containing a water-soluble plasticizer, swelling agent, or softener, is shaped by bringing it into contact with a rigid surface, and subsequently the plasticizer is removed by solution in water.  Articles or coatings of any desired shape may be obtained.  The sheet may be stretched over the rigid surface and then treated with water so as to form a tightly fitting covering.  The sheet may be shaped by blowing, swedging, or other operation.  The plasticizer may be incorporated in the solution or plastic composition from which the sheet is formed, or it may subsequently be applied to the sheet.  The process is applicable to forming coatings on wood, glass, metal, cellulose derivative material, wooden shoe heels, artificial limbs, or table legs, and to the production of articles such as dolls' heads, and vials.  The products may readily be printed or dyed.  Cellulose acetate or other ester or methyl cellulose or other cellulose ether may be used. Water soluble plasticizers specified are ethylene, propylene, and diethylene glycol, and ethers of these glycols, glycerine, ethyl lactate, diacetone alcohol, glycol diacetate, ethylene chlorhydrin mono-, di-, and tri-acetin, di-methyl, ethyl, and butyl tartrate, toluene sulphonamides, and the acetate of glycol monoethyl ether. The sheets may contain other plasticizers such as aryl phosphates, alkyl phthalates, or sulphonamides.  The sheets may be formed by extrusion or casting methods, or by block pressing methods.  The sheets may be further softened by treatment with solvent vapours prior to the shaping process.  In an example a white sheet is made by cutting from a block comprising cellulose acetate, methyl phthalyl ethyl glycollate, triphenyl phosphate, titanium dioxide, diethylene or triethylene glycol, and acetone.  The seasoned sheet is treated with solvent vapour and then moulded or stretched over the article to be covered.  The shaped sheet is leached with water.  In another example, cellulose acetate sheets are treated with a solution of diethylene glycol and diacetin.  In another example, sheets are cut from a block made from cellulose acetate, diacetin or other water soluble plasticizer, and acetone, or obtained by casting, or extrusion, and the sheets are shaped by contact with a rigid surface, and then leached with water.  The Specification as open to inspection under Sect. 91 specifies also the application of the process to the production or shaping of tubes, sausage casings, or caps for sealing bottles.  This subject-matter does not appear in the Specification as accepted.ALSO:A preformed cellulose derivative sheet containing a water-soluble plasticizer, swelling agent, or softener, is shaped by bringing it into contact with a rigid surface, and subsequently the plasticizer is removed by solution in water. Articles or coatings of any desired shape may be obtained.  The sheet may be stretched over the rigid surface and then treated with water so as to form a tightly fitting covering.  The sheet may be shaped by blowing, swedging or other operation.  The plasticizer may be incorporated in the solution or plastic composition from which the sheet is formed, or it may subsequently be applied to the sheet.  The process is applicable to forming coatings on wood, glass, metal, cellulose derivative material, wooden shoe heels, artificial limbs, or table legs, and to the production of articles such as dolls' heads, and vials.  The products may readily be printed or dyed.  Cellulose acetate or other ester or methyl cellulose or other cellulose ether may be used. Water soluble plasticizers specified are ethylene, propylene, and diethylene glycol, and ethers of these glycols, glycerine, ethyl lactate, diacetone alcohol, glycol diacetate, ethylene, chlorhydrin, mono-, di-, and tri-acetin, di-methyl, ethyl, and butyl tartrate, toluene sulphonamides, and the acetate of glycol monoethyl ether. The sheets may contain other plasticizers such as aryl phosphates, alkyl phthalates, or sulphonamides.  The sheets may be formed by extrusion or casting methods, or by block pressing methods.  The sheets may be further softened by treatment with solvent vapours prior to the shaping process.  In an example a white sheet is made by cutting from a block comprising cellulose acetate, methyl phthalyl ethyl glycollate, triphenyl phosphate, titanium dioxide, diethylene or triethylene glycol, and acetone.  The seasoned sheet is treated with solvent vapour and then moulded or stretched over the article to be covered.  The shaped sheet is leached with water.  In another example, cellulose acetate sheets are treated with a solution of diethylene glycol and diacetin.  In another example, sheets are cut from a block made from cellulose acetate, diacetin or other water soluble plasticizer, and acetone, or obtained by casting, or extrusion, and the sheets are shaped by contact with a rigid surface and then leached with water.  The Specification as open to inspection under Sect. 91 specifies also the application of the process to the production or shaping of tubes, sausage casings, or caps for sealing bottles.  This subject-matter does not appear in the Specification as accepted.