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SELECT DISTINCT patent.*, YEAR(date) as year FROM patent LEFT JOIN category ON category.patent = patent.patent AND category.type = patent.type WHERE (category.class = '516') AND (category.subclass = '139') ORDER BY date ASC, patent, type

Total of 1 patents found where: Class is '516'; Subclass is '139';

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T / S Patent Date Description Patentee Category Assigned To
 1939
U 2,155,835 April 25, 1939 Ceramic Insulating Material
Improved ceramic composition using titanium oxide that will fire at typical kiln temperatures		 MCCREERY, George L.
CAMPBELL, Van E.
HIGGINS, Ray
 Ceramic Composition The Ohio Brass Co.

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