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:
Sep. 28, 1999
Filed:
Jan. 22, 1997
Masato Ueda, Tsukuba, JP;
Fumi Yamaguchi, Tsuchiura, JP;
Sumitomo Chemical Co., Ltd., Osaka, JP;
Abstract
An organic electroluminescence device which has a pair of electrodes, at least one of which is transparent or semitransparent, and at least one organic layer formed between the electrodes. The organic layer contains a hole transporting material and a light emitting material in the same or different layer. The hole transporting material contains at least one polysilane whose main chain skeleton is composed of a repeating unit represented by the general formula (1) and a repeating unit represented by the general formula (2): ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 independently represent a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aryl group or a substituted or unsubstituted aralkyl group, Ar.sub.1 represents a substituted or unsubstituted arylene group and Ar.sub.2 represents a substituted or unsubstituted aryl group. The polysilane satisfies the expression 0.2.ltoreq.z.ltoreq.1 where a ratio of the number of the repeating unit (1) and that of the repeating unit (2) to the total number of the repeating units (1) and (2) are z and 1-z, respectively. The polysilane has a weight average molecular weight of not less than 5000 and a hole drift mobility of 10.sup.-3 -10.sup.-1 cm.sup.2 /v/sec. The organic EL device shows excellent characteristics of higher luminance and higher luminous efficiency at lower driving voltage.