Patent GB-451682-A (GB)
Title: Improvements in or relating to filter filling for cigarettes
IPC: D01D5/247
Filed: 1935-02-13
Abstract: A filter filling for cigarettes, cigars, or tobacco pipes which has longitudinally extending passageways or cavities therein is formed by extruding through an orifice a cellulose derivative dissolved in a suitable solvent (preferably together with fibrous material, e.g. finely divided cotton or wood pulp) and also passing through said orifice streams of air or other gas from a plurality of jets and then coagulating the cellulose derivative. Coagulation of viscose solutions may be effected by means of an aqueous bath of sulphuric acid and sodium sulphate, the rod being allowed if desired to remain in the bath for some time for coagulation to be completed, or by heat, e.g. by passing the rod into a heated tube tapered to allow for shrinkage during coagulation.  The size of the extrusion orifice is chosen to give a coagulated rod which only requires cutting to the desired length.  In a modification, cellulose acetate or formate or a mixture thereof dissolved in acetone or other suitable solvent is extruded, together with streams of air, and the rod passes into a chamber in which it meets a counter-current of warm air, or into a bath of water or other coagulant.  Inert fillers such as calcium carbonate or kieselguhr and plasticizers such as tricresyl phosphate or triacetin may be added to the compositions.ALSO:A filter filling for cigarettes, cigars or tobacco pipes which has longitudinally extending passageways or cavities therein is formed by extruding through an orifice a cellulose derivative dissolved in a suitable solvent (preferably together with fibrous material, e.g. finely divided cotton or wood pulp) and also passing through said orifice streams of air or other gas from a plurality of jets and then coagulating the cellulose derivative. Coagulation of viscose solution may be effected by means of an aqueous bath of sulphuric acid and sodium sulphate or by heat, e.g. by passing the rod into aheated tube tapered to allow for shrinkage during coagulation.  The size of the extrusion orifice is chosen to give a coagulated rod which only requires cutting to the desired length.  In In a modification cellulose acetate or formate or a mixture thereof dissolved in acetone or other suitable solvent is extruded together with streams of air and the rod passes into a chamber in which it meets a counter current of warm air, or into a bath of water or other coagulant. Inert fillers such as calcium carbonate or kieselguhr and plasticizers such as tricresyl phosphate or triacetin may be added to the compositions.ALSO:A filter filling for cigarettes, cigars, or tobacco pipes which has longitudinally-extending passageways or cavities therein, is formed by extruding through an orifice a cellulose derivative dissolved in a suitable solvent (preferably together with fibrous material, e.g. finely-divided cotton or wood pulp), and also passing through said orifice streams of air or other gas from a plurality of jets and then coagulating the cellulose derivative. Coagulation of viscose solution may be effected by means of an aqueous bath of sulphuric acid and sodium sulphate or by heat, e.g. by passing the rod into a heated tube tapered to allow for shrinkage during coagulation.  The size of the extrusion orifice is chosen to give a coagulated rod which only requires cutting to the desired length.  In a modification, cellulose acetate or formate or a mixture thereof dissolved in acetone or other suitable solvent is extruded together with streams of air, and the rod passes into a chamber in which it meets a counter-current of warm air, or into a bath of water or other coagulant.  Inert fillers such as calcium carbonate or kieselguhr and plasticizers such as tricresyl phosphate or triacetin may be added to the compositions.