Abstract: The invention relates to a process for the production of cellulosic flat films whereby a solution of cellulose is extruded in an aqueous tertiary amine oxide by means of an extrusion die which has an extrusion gap whereby the solution is moulded in the shape of a film and the extruded solution is led via an air gap to a precipitation bath. The process in accordance with the invention is characterised in that an extrusion die is used which has an extrusion gap b of 220 &mgr;m≦b≦280 &mgr;m. Moreover, the invention relates to flat films, obtainable by the amine oxide process with a thickness d of less than 20 &mgr;m, a width B of more than 30 cm, and a factor f of 65 or less, whereby f is defined as f=d*(MD/TD), d is used in &mgr;m and whereby MD stands for the tenacity of the film in the longitudinal direction (N/mm2) and TD for the tenacity of the film in the transverse direction (N/mm2).

Abstract: The invention relates to a process for the production of a spunlaid fabric containing solvent-spun cellulosic fibers.

Abstract: The invention relates to a process for the production of cellulosic flat films whereby a solution of cellulose is extruded in an aqueous tertiary amine oxide by means of an extrusion die which has an extrusion gap whereby the solution is moulded in the shape of a film and the extruded solution is led via an air gap to a precipitation bath. The process in accordance with the invention is characterized in that an extrusion die is used which has an extrusion gap b of 220 &mgr;m≦b≦280 &mgr;m. Moreover, the invention relates to flat films, obtainable by the amine oxide process with a thickness d of less than 20 &mgr;m, a width B of more than 30 cm, and a factor f of 65 or less, whereby f is defined as f=d*(MD/TD), d is used in &mgr;m and whereby MD stands for the tenacity of the film in the longitudinal direction (N/mm2) and TD for the tenacity of the film in the transverse direction (N/mm2).

Abstract: The invention relates to a process for the production of cellulosic moulded bodies in the form of flat or tubular films and cellulosic membranes in the form of flat or tubular films whereby a solution of cellulose in an aqueous tertiary amine oxide is extruded using an extrusion nozzle whereby the solution can as the case may be also contain additives such as stabilizing and softening agents, pore formers and so on whereby a moulded solution results which has two surfaces and the extruded moulded solution is led over a gap into a precipitation bath and drawn off from the precipitation bath. The process in accordance with the invention is characterized in that the two surfaces of the moulded solution in the gap are each exposed to at least one gaseous medium whereby the medium to which the first surface is exposed differs from the medium to which the second surface is exposed in composition, properties and/or the state of motion.

Abstract: The invention relates to a planar assembly made of a polymer, which planar assembly includes threads interconnected in a net-like manner via connection sites while forming meshes, wherein the threads at least partially are fused together on the connection sites, and is characterized in that the polymer substantially is cellulose.

Abstract: The invention relates to a device for the production of cellulosic tubular films by extruding a solution of cellulose in an aqueous tertiary amine oxide into a precipitant present below the device, which device comprises an extrusion die having a substantially annular extrusion gap, wherein a supply duct for precipitant and a discharge duct for used precipitant are provided in the interior of the ring formed by the extrusion gap, characterized in that the supply duct (3) for the precipitant terminates below the discharge duct (4) for the used precipitant.

Abstract: The invention relates to a process for the production of a spunlaid fabric containing solvent-spun cellulosic fibres.

Abstract: The invention relates to a process for the production of cellulosic flat films whereby a solution of cellulose is extruded in an aqueous tertiary amine oxide by means of an extrusion die which has an extrusion gap whereby the solution is moulded in the shape of a film and the extruded solution is led via an air gap to a precipitation bath. The process in accordance with the invention is characterised in that an extrusion die is used which has an extrusion gap b of 220 &mgr;m≦b≦280 &mgr;m. Moreover, the invention relates to flat films, obtainable by the amine oxide process with a thickness d of less than 20 &mgr;m, a width B of more than 30 cm, and a factor f of 65 or less, whereby f is defined as f=d*(MD/TD), d is used in &mgr;m and whereby MD stands for the tenacity of the film in the longitudinal direction (N/mm2) and TD for the tenacity of the film in the transverse direction (N/mm2).

Abstract: The invention relates to a process for the manufacture of cellulosic flat films and of cellulosic membranes in the form of flat membranes whereby a solution of cellulose in an aqueous tertiary amine oxide is extruded by means of an extrusion nozzle, which has an extrusion gap, whereby the solution is shaped in the form of a film and the solution is led into a precipitation bath via an air gap and is characterized in that an extrusion nozzle is used which has an extrusion gap with a minimum length of 40 cm.

Abstract: The invention relates to a process for the manufacture of cellulosic flat films and cellulosic membranes in the form of flat membranes whereby a solution of cellulose in an aqueous tertiary amine oxide is moulded in film form using an extrusion nozzle which has an oblong extrusion gap and is led into a precipitation bath via an air gap whereby the cellulosic flat film is formed in the precipitation bath, characterized in that the cellulosic flat film is stretched in the transverse direction after entering the precipitation bath.

Abstract: The invention relates to a process for producing a strengthened fiber assembly containing cellulosic fibers with the cellulose being present in the crystalline structure of cellulose II, by contacting the fiber assembly with an aqueous solution of N-methylmorpholine-N-oxide (NMMO) at elevated temperature and subsequently washing the fiber assembly, characterized in that contacting is effected in a manner that from the relation-947+0.30.times.log.sub.(10) t+0.046.times.T-3.53.times.C +645.times.log.sub.(10) Cwherein t indicates the time in minutes during which the fiber assembly is contacted with the aqueous NMMO solution, T indicates the temperature of the aqueous NMMO solution in .degree.C. and C is the concentration of NMMO in % by mass, based on the aqueous NMMO solution, a number in the range of 0.30 to 1.70 results with the proviso that the temperature T is smaller than 130.degree. C. and the concentration C ranges between 70 and 84 % by mass.

Abstract: The invention relates to a process for the manufacture of cellulosic flat films and cellulosic membranes in the form of flat membranes whereby a solution of cellulose in an aqueous tertiary amine oxide is moulded in film form using an extrusion nozzle which has an oblong extrusion gap and is led into a precipitation bath via an air gap whereby the cellulosic flat film is formed in the precipitation bath, characterized in that the cellulosic flat film is stretched in the transverse direction after entering the precipitation bath.