Abstract: A method for producing a heating filament made of a composite material and having a longitudinal axis is provided. Carbon fibers are embedded in a matrix made of carbon and a planar structure is prepared that contains carbon fibers in a textile bond. The planar structure is impregnated with thermoplastic material, and then the impregnated planar structure is carbonized in a protective gas or vacuum while forming the composite material. The planar structure is prepared from a fiber composite material, in which plastic threads made of the thermoplastic material are incorporated into the textile bond of the planar structure. The resulting carbon heating filament provides for the smallest possible material loss in the cutting process from a large surface area, namely to form a strip-shaped semi-finished product. Also, the resulting carbon heating filament filament has a high specific electrical resistance and is distinguished by high mechanical stability.

Abstract: A method for manufacturing an electrically conductive material includes steps of: (a) providing a carbon fiber; (b) providing a plastic fiber that differs from the carbon fiber; (c) producing a mixture in the form of a two-dimensional mat from the carbon fiber and the plastic fiber; (d) drying the mixture, optionally; (e) consolidating the mixture; (f) cutting the mixture to size, optionally; (g) carbonizing the mixture, wherein the carbonized plastic fibers form a carbon-based matrix possessing electrical conductivity that at least partially surrounds the carbon fibers. Electrically conductive materials obtained by the method have an increased electrical resistance. An emitter is specified that contains a transparent or translucent housing and an electrically conductive material as above. These now allow emitters of virtually any length to be operated at customary line voltages.

Abstract: A method is provided for manufacture of an electrically conductive material, including the steps of: (a) providing a structure made of electrically conductive fibers, and (b) producing a carbon-based, electrically conductive matrix at least partially enveloping the electrically conductive fibers. Before or after producing the matrix, at least part of the electrically conductive fibers are interrupted in the direction of possible current flow. Electrically conductive materials obtained in corresponding manner are also provided. An emitter is specified that contains a transparent or translucent housing and an electrically conductive material according to the above. The electrically conductive materials have an increased electrical resistance. These allow emitters of virtually any length to be operated at customary line voltages.

Abstract: A method for manufacturing an electrically conductive material includes steps of: (a) providing a carbon fiber; (b) providing a plastic fiber that differs from the carbon fiber; (c) producing a mixture in the form of a two-dimensional mat from the carbon fiber and the plastic fiber; (d) drying the mixture, optionally; (e) consolidating the mixture; (f) cutting the mixture to size, optionally; (g) carbonizing the mixture, wherein the carbonized plastic fibers form a carbon-based matrix possessing electrical conductivity that at least partially surrounds the carbon fibers. Electrically conductive materials obtained by the method have an increased electrical resistance. An emitter is specified that contains a transparent or translucent housing and an electrically conductive material as to above. These now allow emitters of virtually any length to be operated at customary line voltages.