Claims
- 1. A method of forming a ceramic coating on a substrate comprising:
- coating the substrate with a solution comprising a solvent and hydrogen silsesquioxane resin with a number average molecular weight between about 700 and about 6000 and a dispersity less than about 3.0;
- evaporating the solvent to deposit a preceramic coating on the substrate; and
- subjecting the preceramic coating to a temperature sufficient to facilitate conversion of the preceramic coating to a ceramic coating.
- 2. The method of claim 1 wherein the solvent is selected from the group consisting of alcohols, aromatic hydrocarbons, alkanes, ketones, esters, glycol ethers and cyclic dimethylpolysiloxanes and is present in an amount sufficient to dissolve the hydrogen silsesquioxane to between about 0.1 and about 50 weight percent.
- 3. The method of claim 1 wherein the preceramic coating is subjected to a temperature of about 20.degree. up to about 1000.degree. C. for up to about 6 hours.
- 4. The method of claim 3 wherein the preceramic coating is subjected to the temperature under an a gaseous atmosphere selected from the group consisting of air, O.sub.2, an inert gas, ammonia, and amines.
- 5. The method of claim 1 wherein the solution also contains a modifying ceramic oxide precursor comprising a compound containing an element selected from the group consisting of titanium, zirconium, aluminum, tantalum, vanadium, niobium, boron and phosphorous wherein the compound contains at least one hydrolyzable substituent selected from the group consisting of alkoxy or acyloxy and the compound is present in an amount such that the ceramic coating contains 0.1 to 30 percent by weight modifying ceramic oxide.
- 6. The method of claim 1 wherein the solution also contains a platinum or rhodium catalyst in an amount of about 5 to about 500 ppm platinum based on the weight of the fraction.
- 7. The method of claim 5 wherein the solution also contains a platinum or rhodium catalyst in an amount of about 5 to about 500 ppm platinum based on the weight of the fraction.
Parent Case Info
This is a divisional of copending application Ser. No. 07/618,865 filed on Nov. 28, 1990 now U.S. Pat. No. 5,063,267.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
4911992 |
Haluska et al. |
Mar 1990 |
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Divisions (1)
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Number |
Date |
Country |
Parent |
618865 |
Nov 1990 |
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