Granted Patent
Utility
US 5,246,491 · App. 07/910,397
Paper sizing agent composition
Inventors:
Yoshio Takahashi, Shigeto Hatanaka
Patented Case
View Patent ↗
Granted: Sep 21, 1993
Filed: Jul 8, 1992
Inventors
Yoshio Takahashi
Shigeto Hatanaka
Assignee (at issue)
Mitsubishi Oil Co., Ltd.
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.