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:
May. 26, 1992
Filed:
Apr. 05, 1990
Satoshi Ozawa, Hitachi, JP;
Naoto Oki, Hitachi, JP;
Yasuhisa Shibata, Ibaraki, JP;
Hiroyuki Miyagi, Kokubunji, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An anion-selective electrode of the present invention comprises, as anion sensitive substance, a tetraalkyl type, quaternary phosphonium salt having four alkyl radicals, each having 8 to 24 carbon atoms; a combination of a tetraalkyl onium salt having four alkyl radicals each having 10 to 24 carbon atoms, and an onium salt having one alkyl radical with 1 to 20 carbon atoms and three alkyl radicals with the proviso that the number of carbon atoms contained in the three alkyl radicals each is larger than that contained in the one alkyl radical; or a tetraalkyl type, quaternary onium salt having an asymmetrical molecular structure. The anion-selective electrode has good properties including selectivity and measurement accuracy. An anion-selective, field effect transistor or a chemical analysis apparatus, provided with the anion-selective sensitive substance, is suitable for measuring an anion concentration with a high accuracy.