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. 26, 2023
Filed:
Feb. 18, 2021
Sumitomo Chemical Company, Limited, Tokyo, JP;
Satoshi Kobayashi, Tsukuba, JP;
Makoto Anryu, Tokyo, JP;
Mika Shirasaki, Tsukuba, JP;
Hiroyuki Hayasaka, Osaka, JP;
Toshiaki Sasada, Tsukuba, JP;
SUMITOMO CHEMICAL COMPANY, LIMITED, Tokyo, JP;
Abstract
A method of producing a film having excellent external quantum efficiency when used in a light emitting layer of a light emitting device is provided. A method of film production includes preparing an ink containing a specific metal complex, storing the ink for 3 days or more under light shielding, and forming a film by using the stored ink. The total content of metal complexes having a molecular weight larger by 16, 32 or 48 than that of the specific metal complex according to an area percentage value determined by liquid chromatography is 0.6 or less when the content of the specific metal complex is taken as 100.