PD

Paul F. Duffer

PI Ppg Industries: 9 patents #107 of 1,216Top 9%
📍 New Kensington, PA: #25 of 233 inventorsTop 15%
🗺 Pennsylvania: #9,221 of 74,527 inventorsTop 15%
Overall (All Time): #593,205 of 4,157,543Top 15%
9
Patents All Time

Issued Patents All Time

Showing 1–9 of 9 patents

Patent #TitleCo-InventorsDate
4606946 Method of applying interleaving material to glass sheets Joseph D. Kelly, Helmut Franz 1986-08-19
4568605 Acidified powdered interleaving Helmut Franz, Joseph D. Kelly 1986-02-04
4530889 Acidified powdered interleaving Helmut Franz, Joseph D. Kelly 1985-07-23
4529648 Method of applying interleaving material to glass sheets Joseph D. Kelly, Helmut Franz 1985-07-16
4489106 Two step interleaving method Helmut Franz, Joseph D. Kelly 1984-12-18
4487807 Mixed acid stain inhibitor Joseph D. Kelly, Helmut Franz 1984-12-11
4447496 Organotin surface treatment and interleaving material for glass sheets Helmut Franz, Joseph D. Kelly 1984-05-08
4360544 Organotin surface treatment and interleaving material for glass sheets Helmut Franz, Joseph D. Kelly 1982-11-23
4254046 Method for making dimethyltin difluoride Helmut Franz, James H. Hanlon 1981-03-03