A federal jury today awarded more than $10 million in damages to Washington dentist and inventor Robert I. Schattner, who contends that three chemical firms sabotaged his efforts to market a lucrative sterilizer-disinfectant he had invented.

The civil jury of five women and one man made the award after an 11-week trial before U.S. District Judge Walter E. Black Jr.

Schattner, 59, inventor of the antiseptic mouth spray Chloroseptic, lives in Bethesda and maintains an office in Washington, where he conducts research in germicides, disinfectants and sterilizers.

Schattner attorney Philip L. Cohan said the federal jury today awarded $10.2 million, most of it in punitive damages, against Chemed Corp., of Cincinnati, and two subsidiaries, Unidisco and Veratex, of Troy, Mich., for patent infringement, unfair competition and wrongful interference with Schattner's business contracts.

Attorneys for the chemical firms could not be reached for comment.

Cohan said that Schattner invented a product in the 1970s called Sporicidin, a chemical solution for sterilizing and disinfecting medical and dental instruments.

After obtaining a patent for it in 1978, Schattner entered into a license agreement with Girard Health Care Products Inc., of Chicago, for marketing the product. Subsequently, Cohan said, Girard entered into sublicense marketing agreements with Unidisco and Veratex without Schattner's consent, a violation of the master agreement with Girard.

After the sublicense agreements were ruled invalid in an arbitration proceeding, Unidisco and Veratex approached Schattner directly to get the right to sell Sporicidin, but were turned down, Cohan said.

The firms still had about 14,000 quarts of the chemical left over from the sublicense period, Cohan said. Without paying Schattner, he said, the firms sold the entire quantity to various dental dealers for about $500,000, placing "shoddy" labels on the individual bottles to cheapen their value.

Next, Cohan said, they planned to manufacture an identical sterilizer-disinfectant using Schattner's formula, and sued Schattner for having what they called an invalid patent. Schattner then countersued.