US Patent 7514158 Coumarin compound

A method for producing a coumarin compound represented by Formula 1, which comprises a step of reacting a coumarin compound represented by Formula 1 with a compound having an aldehyde group and an activated methylene group; luminous agents for organic EL elements and organic EL elements which all comprise the coumarin compound; and displaying panels and information displaying apparatuses using the organic EL elements:ø(Z)m  Formula 1wherein in Formula 1, ø is an aromatic ring, heterocycle, or a combination thereof, each Z is the same or a different coumarin group represented by Formula 2; and m is an integer of two or more;