Abstract: A melt-blowing head is used to produce long thermoplastic filaments which are collected on a sieve belt and form crossing welds at cross-over points. The resulting mat may be calendered and is composed of filaments having a diameter of less than 100 .mu.m and a degree of crystallinity which is less than 45%. The mat is heated to a stretching temperature of 80 to 150.degree. C. and is then biaxially stretched by 100 to 400% before being thermally fixed at a higher temperature. The result is a nonwoven web which can have a greater strength for a given area weight or a reduced area weight for a given strength than earlier systems.

Abstract: A novel pitch material made from coal tar pitch has:a) mesophase content of .ltoreq.2%,b) content of toluene-insolubles (.beta.-resin) between 58 and 75%,c) content of quinoline-insolubles of <2%,d) softening point in the 200.degree. to 300.degree. C. range, according to the Kramer-Sarnow (KS) measurement,e) content of volatile matter .ltoreq.20% andf) ash content of .ltoreq.0.06%.The pitch material of high coke yield (80 to beyond 90%) is suitable for the manufacture of molded carbonaceous shapes of high quality and of pitch coke. A further application would be as impregnation agent or bind. The method of making new pitch uses hot filtration in the presence of a filtration and followed by thin-film evaporation.