Electrophoresis process for preparation of ceramic fibers

A process for the preparation of a ceramic fiber, said process comprising the steps of:

• a) providing a sol comprising metal hydrate particles selected from the group consisting of aluminum hydrate, yttrium hydrate, and mixtures thereof, said particles being less than 150 Angstroms in size, said sol also comprising an alcohol such that the molar ratio of said alcohol to said metal hydrate is from about 50 to about 70;
• b) electrophoretically depositing particles from said sol onto an electrically conductive fiber core by applying a direct current potential between said fiber core and an anode, said potential being from about 0.1 to about 100 volts, for sufficient time to obtain a uniform deposit of metal hydrate on said fiber core, said deposit being of greater thickness than the diameter of said fiber core, while providing means for removal of hydrogen gas generated by said electrophoresis;
• c) removing the metal hydrate coated fiber core from said sol;
• d) heating the metal hydrate coated fiber core to dry the coating and to transform said metal hydrate to the corresponding metal oxide;
• and
• e) recovering the ceramic fiber.