John H. Davis Sr., 88, former chairman of the board of Judd and Detweiler, Inc., died Tuesday at the Bethesda-Silver Spring Nursing Home after a long illness.

A third generation Washingtonian, Mr. Davis started work at Judd and Detweiler, which became Washington's largest commercial printing firm, while he was still in grammar school.

He eventually rose to general manager, vice president and president and was named chairman of the board in 1953. He resigned as chairman in 1960 but continued to serve as a director for a number of years.

During his tenure, Mr. Davis introduced many innovations in printing the National Geographic Magazine, one of the major productions of the firm. He also helped introduce a management council for the company, which was considered unique for its time.

Mr. Davis was a former member of the Rotary Club and a lifetime member of the Printing Industry of Washington. He also was a lifetime director of the Boys Club of Greater Washington and belonged to the Early Birds Breakfast Club and the Columbia Country Club.

He is survived by two sons, John H. Jr. and Richard A., both of Bethesda; four daughters, Sydney D. Hartford, of Washington, Katherine D. Carrico, of Annandale, Barbara D. Ruppert, of Chevy Chase, and Mary D. Connors, of Potomac, 24 grandchildren and nine great-grandchildren.