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The vitreous carbon disclosed herein is prepared from intimate uniform mixtures of powder or otherwise blendable form of 20-80% by weight of a solid phenolic-aldehyde Novolak resin and of 20-80% by weight of a solid phenolic-aldehyde resol resin, the percentages being based on the combined weight of

The vitreous carbon disclosed herein is prepared from intimate uniform mixtures of powder or otherwise blendable form of 20-80% by weight of a solid phenolic-aldehyde Novolak resin and of 20-80% by weight of a solid phenolic-aldehyde resol resin, the percentages being based on the combined weight of the Novolak and resol resins, and the aldehyde in said Novolak resin comprising at least 50 molar percent, preferably substantially 100 percent, furfuraldehyde, together with a carbonaceous filler, preferably graphite, in a proportion as high as 76% by weight based on the total composition. Generally the graphite may comprise 30-70%, advantageously 35-65% and preferably 40-60% of the molding composition. The vitreous carbon is improved in electrical properties and in the capability of being shaped into large thin plates which are much more stress-free than otherwise produced. The intimate mixture of the resins used for this preparation is advantageously made by blending resin components having a particle size of less than 40 mesh, preferably less than 100 mesh.

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1. A process for preparing a vitreous carbon from a solid thermosettable intimate blend comprising 30-76 percent by weight of a finely divided carbonaceous particulate filler and 24-70 percent by weight of a finely divided phenolic resin mixture comprising 20-80 parts by weight of a phenolic-furfura

1. A process for preparing a vitreous carbon from a solid thermosettable intimate blend comprising 30-76 percent by weight of a finely divided carbonaceous particulate filler and 24-70 percent by weight of a finely divided phenolic resin mixture comprising 20-80 parts by weight of a phenolic-furfuraldehyde Novolak resin, which is fusible upon heating, and 20-80 parts by weight of a phenolic-aldehyde resol resin, which is thermosettable upon heating, the sum of said parts of Novolak and resol resins totaling 100 parts by weight, the aldehyde in said Novolak comprising at least 50 molar percent of furfuraldehyde, comprising the steps of: (1) grinding said phenolic furfuraldehyde Novolak resin to a particle size of less than 40 mesh on a U.S. Standard sieve; (2) grinding said phenolic-aldehyde resol resin to a particle size of less than 40 mesh on a U.S. Standard sieve; (3) mixing said ground resins together with said finely divided carbonaceous powder to a homogeneous mixture; (4) molding the resultant mixture at a temperature of 100°-180° C. and a pressure between 500 pounds per square inch and 8 tons per square inch; and (5) heating the resultant molded product gradually up to a temperature of 600°-700° C. with the temperature increased at a rate of 1°-5° C. per hour, then above the range of 600°-700° C. at an increasing rate of 10°-50° C. per hour up to 800°-850° C. and thereafter at 20°-25° C. per hour up to a maximum temperature of 1800°-3000° C., which maximum temperature is held for at least 24 hours. 2. The process of claim 1, in which after being held at maximum temperature for at least 24 hours the temperature is gradually dropped at a rate of 10°-20° C. per hour. 3. The process of claim 2 in which both said resins are ground to a particle size not exceeding 32 microns in diameter. 4. The process of claim 1 in which said mixture of resin and carbonaceous powder is further pulverized to a finer size, then densified and reground to a particle size suitable for molding. 5. The process of claim 4, in which said step of mixing said ground resins is performed in an extruder or on heated rolls. 6. The process of claim 5 in which said step (2) is effected in an air mill, impact grinder or ball mill. 7. The process of claim 6 in which said step (3) is effected on a differential 2-roll heated mill. 8. The process of claim 7, in which the front roll of said mill is maintained at 220°-230° F. and the back roll at 80°-100° F. 9. The process of claim 4, in which said steps (1) and (2) are effected to produce a particle size of less than 100 mesh for both said Novolak and said resol resins. 10. The process of claim 4, in which said step (3) is effected to produce a homogeneous blend of particles having a size no greater than 32 microns. 11. The process of claim 4 in which said molding is effected at a temperature of 149°-166° C. 12. A process for preparing a shaped molded object from an intimate blend of a finely divided carbonaceous powder and a mixture of a phenolic-furfuraldehyde Novolak resin, the aldehyde in said Novolak comprising at least 50 molar percent of furfuraldehyde, and a phenolic-aldehyde resol resin comprising the steps of: (1) grinding the solid phenolic furfuraldehyde Novolak resin to a particle size of less than 40 mesh on a U.S. Standard sieve; (2) grinding the solid phenolic-aldehyde resol resin to a particle size of less than 40 mesh on a U.S. Standard sieve; (3) mixing said ground resins together with said finely divided carbonaceous powder to a homogeneous mixture suitable for molding, said carbonaceous powder being used in a proportion of 30-76 percent based on total weight of carbonaceous powder and resin powders, and said Novolak and resol powders being used in a proportion of 20-80 percent by weight of said Novolak and 20-80 parts by weight of said resol, the combined weight of said Novolak and said resol totalling 100 parts by weight; and (4) molding the resultant mixture at a temperature of 100°-180° C. and a pressure between 500 pounds per square inch and 8 tons per square inch. 13. A thermoset resin shaped object produced according to the process of claim 12. 14. The process of claim 12 in which both said resins are ground to a particle size not exceeding 32 microns in diamter. 15. The process of claim 12 in which said mixture of resin and carbonaceous powder is further pulverized to a finer size, then densified and reground to a particle size suitable for molding. 16. The process of claim 15, in which said step of mixing said ground resins is performed in an extruder or on heated rolls. 17. The process of claim 16 in which said resol resin grinding is effected in an air mill, impact grinder or ball mill. 18. The process of claim 17 in which said step mixing is effected on a differential 2-roll heated mill. 19. The process of claim 18 in which the front roll of said mill is maintained at 220°-230° F. and the back roll at 80°-100° F. 20. The process of claim 15 in which said resin grinding steps are effected to produce a particle size of less than 100 mesh for both said Novolak and said resol reins. 21. The process of claim 15 in which said mixing step is effected to produce a homogeneous blend of particles having a size no greater than 32 microns. 22. The process of claim 15 in which said molding is effected at a temperature of 149°-166° C. 23. A thermoset resin shaped object prepared according to the process of claim 12. 24. A shaped object of claim 23 comprising a thin plate having a thickness of 0.04-0.05 inch. 25. A shaped object of claim 24 having other dimensions up to 50 inches by 50 inches.