METHOD OF PRODUCING NONWOVEN CARBON MATERIAL Russian patent published in 2003 - IPC

FIELD: textile industry. SUBSTANCE: method involves forming nonwoven material of viscose raw material from two outer needle stitchable layers with number of punctures ranging from 60×10⁴ to 250×10⁴ per 1 sq.m and surface density of 150-450 g/sq.m, said layers being produced from viscose stapled filaments of at least 0.18 mm length, and inner carcass layer with surface density of 9.5- 38.0 g/sq.m, said inner carcass layer being composed of continuous viscose threads with density of 192 tex or 380 tex and extending in parallel with one another along outer layers; providing surface density ratio of nonwoven outer layers and inner carcass layer of (15.5-47.0):(1-4): (15.5-47.0); performing needle stitching of viscose raw material for obtaining of nonwoven material having volumetric density of 45.5-49.2 kg/cu.m and total number of punctures of from 120×10⁴ to 50×10⁴ per 1 sq.m; carbonizing resultant nonwoven material in nitrogen medium while permanently increasing temperature from 240 C to 600-700 C for 10-15 min; activating resultant carbonized nonwoven material with adjustable volumetric density and air-permeability at final temperatures of 650-850 C for 15-50 min or graphitizing said material at temperatures of 1,500-2,500 C for 7-20 min. Material of such structure may be used for manufacture of heat-insulating, current-conductive and filtering materials. EFFECT: adjustable strength, improved air-permeability, filtering and sorptive capacity of nonwoven material due to reduced volumetric density of carbon materials and wider range of usage. 3 cl, 1 dwg