Application of Ewald Katzschmann

SMITH, Judge.

As an improvement on the process of his U. S. Patent 2,894,978 appellant discovered' that undesirable by-products were reduced and an improved space-time yield was achieved in the production of esters of phthalic acids by 1) using xylenes of 98.5% concentration and 2) using p-xylene or m-xylene. His application for patent on this improved process1 has been refused under 35 U.S.C. § 103 as covering but an obvious modification of the process of appellant’s Canadian patent No. 557,345, issued May 13, 1958. Appellant states that this patent corresponds to his U. S. patent which was…