Douglas Blackburn

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Port Clinton, OH, US

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Patents Grantslast 30 patents

Information Patent Grant
Oil well cementing products with synthetic gypsum and methods
- Patent number 9,346,996
- Issue date May 24, 2016
- United States Gypsum Company
- Dennis Mark Lettkeman
- C09 - DYES PAINTS POLISHES NATURAL RESINS ADHESIVES MISCELLANEOUS COMPOSITION...
Information Patent Grant
Low fiber calcination process for making gypsum fiberboard
- Patent number 7,918,950
- Issue date Apr 5, 2011
- United States Gypsum Company
- Marsha S. Skinner
- C04 - CEMENTS CONCRETE ARTIFICIAL STONE CERAMICS REFRACTORIES

Patents Applicationslast 30 patents

Information Patent Application
COMPOSITIONS WITH SYNTHETIC GYPSUM AND METHODS
- Publication number 20160107931
- Publication date Apr 21, 2016
- United States Gypsum Company
- Dennis Mark Lettkeman
- C04 - CEMENTS CONCRETE ARTIFICIAL STONE CERAMICS REFRACTORIES
Information Patent Application
LOW FIBER CALCINATION PROCESS FOR MAKING GYPSUM FIBERBOARD
- Publication number 20090159173
- Publication date Jun 25, 2009
- United States Gypsum Company
- Marsha S. SKINNER
- C04 - CEMENTS CONCRETE ARTIFICIAL STONE CERAMICS REFRACTORIES