The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 10, 1984
Filed:
Jul. 22, 1983
Applicant:
Inventor:
Thomas L Peters, Midland, MI (US);
Assignee:
The Dow Chemical Company, Midland, MI (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B44C / ; C03C / ; C03C / ;
U.S. Cl.
CPC ...
156663 ; 65 31 ; 252 793 ; 252 794 ; 427309 ;
Abstract
An improved process for etching (eroding) the inner surface of a glass capillary column in which ammonium bifluoride in liquid methanol is passed slowly through the capillary bore for a prolonged period, followed by rinsing with methanol, thereafter a gradually diluting rinse mixture of methanol and water, and finally a pure water rinse. A very fine structured etch of uniform depth is produced with no apparent air entrainment making the columns suitable for all standard stationary phase coating procedures.