The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 10, 1992
Filed:
Jun. 21, 1990
Applicant:
Inventors:
Thomas G Krivak, Akron, OH (US);
Timothy A Okel, Trafford, PA (US);
Melvin P Wagner, Wadsworth, OH (US);
Assignee:
PPG Industries, Inc., Pittsburgh, PA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C01B / ;
U.S. Cl.
CPC ...
423339 ; 423335 ; 424 49 ;
Abstract
Reinforced precipitated silica having, on a coating-free and impregnant-free basis, a surface area of from about 220 to about 340 square meters per gram, a pore diameter at the maximum of the volume pore size distribution function of from about 9 to about 20 nanometers, and a total intruded volume of from about 2.6 to about 4.4 cubic centimeters per gram, is produced by a process wherein precipitated silica is heavily reinforced using a multiplicity of precipitation and aging steps.