Granted Patent
Utility
US 4,988,752 · App. 07/359,247
Colored thermoplastic resin composition
Inventors:
Rainer Hamprecht, Michael Kressner, Georg Pape
Patented Case
View Patent ↗
Granted: Jan 29, 1991
Filed: May 31, 1989
Inventors
Rainer Hamprecht
Michael Kressner
Georg Pape
Assignee (at issue)
Bayer Aktiengesellschaft
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.