Granted Patent
Utility
US 6,133,331 · App. 09/125,272
Expanded particles of polyolefin resin and process for preparing the same
Inventors:
Masaharu Oikawa, Kazuo Tsurugai, Hisao Tokoro
Patented Case
View Patent ↗
Granted: Oct 17, 2000
Filed: Aug 13, 1998
Inventors
Masaharu Oikawa
Kazuo Tsurugai
Hisao Tokoro
Assignee (at issue)
JSP Corporation
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.