TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Composition: The mixture of non-polymeric compound further comprises two or more different linking group-containing compounds of formulae: (R1Y2)p((Z2Y2)mR2Y3)nZ2Y4R3, (R1Y1)p((Z1Y2)mR2Y3)nZ2Y4R3 and (R1Y1)p((Z1Y2)mR2Y3)nZ2Y4R3, and has glass transition temperature of more than 20 degrees C. The organic light-emitting layer contains a light-emitting material selected to produce blue light, charge-transporting material having triplet energy of more than 2.60 eV, and charge-transporting material having a band gap of more than 3 eV, and has glass transition temperature of less than 25 degrees C. The low-glass transition temperature crosslinkable plasticizer is chosen from compounds of formulae (I)-(III). The organic light-emitting layer contains a non-crosslinkable small molecule host material, non-crosslinkable polymeric host material and non-crosslinkable charge transporting material chosen from polyvinyl carbazole, tris(8-hydroxyquinolinato)aluminum and 2-(4-biphenylyl)-5-(4-tert-butyl-phenyl)-1,3,4-oxadiazole. The mixture further contains molecular glass mixture chosen from intermediate glass mixture 1 comprising free hydroxyl and indole derivative, intermediate glass mixture 2 comprising indole derivative, intermediate glass mixture 3 comprising indole derivatives, glass mixture 1, glass mixture 2, glass mixture 3, glass mixture 4, glass mixture 5, glass mixture 6, glass mixture 7 and molecular glass mixture of example 1.m=0 or 1;n=0 to integer at which compound becomes polymer;p=1-8;R1,R3=monovalent aliphatic or cycloaliphatic 1-20C hydrocarbyl, aryl, multicyclic aryl, monovalent moiety containing crosslinkable groups or polymerizable groups;R2,Z1,Z2=multivalent aliphatic or cycloaliphatic 1-20C hydrocarbyl or aryl;andY1-Y4=linking group. Preferred Definitions:    crosslinkable groups and polymerizable groups=vinyl, allyl, acryl and methacryl;and    multivalent charge-transporting group=electron-transporting group, hole-transporting group, bipolar charge-transporting group or electroluminescent group.