| 摘要 |
PROBLEM TO BE SOLVED: To obtain bright-red luminescence by using a luminescent layer obtained by continuously laminating two components of Eu complex and Alq3 or laminating a mixture of two components. SOLUTION: Eu complex contained in a luminescent layer is represented by formula I. In the formula, R1 and R2 show alkyl and/or allyl compounds, and at least one compound contain conjugated double bonds. R3 indicates a phenyl group, a methyl group, or a methoxy group. Alq3 is represented by formula II. When the Eu complex and the Alq3 are laminated, preferably, the thickness of the Eu complex is limited to 300-700Å, and that of the Alq3 is limited to 100-300Å. The mixing ratio of Alq3 to Eu is preferably 30-60 parts Alq3 to 100 parts Eu complex. An organic EL element formed by incorporating the Eu complex and the Alq3 as a luminescent layer shows sufficient luminescence at a low voltage of 1-2 V, and can prolong service life to up to about 50,000 hours.
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