| 摘要 |
1441705 Pitch-tar oil binding agent CINDU CHEMIE BV 28 March 1974 [17 April 1973] 13898/74 Heading C5E A binding agent for refractory materials which is workable in cold condition is produced from coil tar by mixing a pitch having a softening point (ring-and-ball) of at least 90‹ C. and a content of C2-resins of at least 20% with a tar oil fraction no more than 20% of which boils at 250‹ C. and at least 80% of which boils at 300‹ C. in a weight ratio of pitch to tar oil of 55 : 45 to 65 : 35. The binding agent may have a content of toluene-insoluble components higher than 20%, a content of anthracene oil-insoluble components less than 10%, whereas the difference between the values is at least 12%, with a viscosity (H÷ppler-Viskowaage, ball Nr2) of 50 to 100 P/20‹ C. and having a flash point higher than 100‹ C. The pitch may be produced by subjecting crude coal tar to a distillation until a residue is obtained having a softening point of 80‹ to 90‹ C. and further heating the residue to raise the softening point by at least 10‹ to 20‹ C. The tar oil is obtained as a fraction of the distillation of crude tar and may have the following boiling range (ASTM-D246): 1% at 225‹ C., 20% at 250‹ C., min. 80% at 300‹ C., 95% at 325‹ C. Refractory articles are produced by mixing the binding agent with components usual for refractory materials. |
