Method for the carbonization of an at least inherently stable two-dimensional textile structure

Abstract

The invention relates to a method for the carbonization of an at least inherently stable two-dimensional textile structure, according to which preoxidized fibers or a mixture of preoxidized and non-oxidized fibers is combined to give a two-dimensional structure and is solidified. Said two-dimensional structure is heated up to temperatures ranging from 600° C. to 900° C. line by line or column by column by means of a laser beam and while supplying air, and the temperature increases as the process output increases.

What is claimed is:  
     
         1 . A method for carbonizing an at least inherently stable textile fabric, in which preoxidized or a mixture of preoxidized and non-oxidized fibers are combined to form a fabric, and are stiffened, 
 wherein the textile fabric is heated under the admission of air, by a laser beam, by lines or columns, to temperatures of between 600° C. and 900° C., the heating taking place with increasing process power.    
     
     
         2 . The method as recited in  claim 1 , 
 wherein the process power is varied in steps between 0.01 und 0.5 watt-seconds g −1 .    
     
     
         3 . The method as recited in  claim 1  or  2 , 
 wherein the low process powers are input repeatedly.  
 
     
     
         4 . The method as recited in one of claims  1  through  3 , 
 wherein the heating is effected using a CO 2  laser.  
 
     
     
         5 . The device as recited in one of claims  1  through  4 , 
 wherein the laser beam is moved by motor and is directed along adjoining paths in such a way over the surface of the fabric that the fabric is irradiated in all surface zones substantially consistently.  
 
     
     
         6 . A carbonized nonwoven fabric produced in accordance with one or more of the claims  1  through  4 , 
 wherein it has a flexural rigidity of about 8 Taber to about 1 Taber, a tensile strength (machine running direction) of 0.4 to 4 N/mm 2  and a tensile strength (transversely to the machine running direction) of 0.7 to 4 N/mm 2 , an elongation property of 0.12 to 14 (flexible) %, an elongation property (transverse) of 0.15 (rigid) to 19%, as well as an air permeability at 200 Pa pressure difference of 200 to 1600 l(m 2 *s).