Process for the manufacture of waxes for carbon paper
AssigneeHoechst Aktiengesellschaft
InventorsKlaus Rieger, Karl-Heinz Stetter, Josef Wildgruber
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Abstract
For coating carbon paper waxes are required which are not only capable to disperse high amounts of carbon black but also have good oil binding properties. For this purpose natural waxes carrying ester groups are treated with oxygen until they have a high carbon black absorption. The waxes are oxidized in the melt. They can also be oxidized in admixture with hydrocarbon waxes or the derivatives thereof.
Claims12
A process for the manufacture of a carbon paper wax having a carbon black absorption in the range of from 80 to 140% by weight and an oil binding temperature of at least 30.degree. C. by treating a molten natural wax having ester wax character with an oxygen-containing gas, which comprises treating the molten wax at a temperature in the range of from its melting point to 250.degree. C with oxygen, air, or another oxygen-containing gas in an amount of from 0.01 to 10 m.sup.3 per hour and per kilogram of wax, throughout the treatment maintaining the oxygen in excess and intensely mixing same with the wax, continuing the treatment until a carbon paper wax is obtained having a carbon black absorption within said range, thereby producing a wax having an acid number which does not exceed the acid number of the starting wax.
Dependencies are inferred from the claim text.