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:
Oct. 26, 1993
Filed:
Dec. 13, 1991
Kunio Imai, Saitama, JP;
Masanao Shinkai, Saitama, JP;
Takeo Wakimoto, Saitama, JP;
Yasuhiko Shirota, Toyonaka, JP;
Pioneer Electronic Corporation, Tokyo, JP;
Abstract
An organic EL element comprises a cathode, an EL layer of organic compound, a first hole transport layer of organic compound, a second hole transport layer of organic compound and an anode which are laminated in sequence, wherein the second hole transport layer is made of a substance represented by the following chemical formula 1: ##STR1## where R each independently represents a hydrogen atom, an alkyl group of from 1 to 6 carbon atoms, a halogen group, a cyano group, a nitro group, a primary, secondary or tertiary amino group, or an aryl group of from 6 to 15 carbon atoms. This organic EL element prevents a leakage current and emits light stably for a long time.