Com. epoxy resins, Bakelite's Ruetapox 0162 and Vantico's Araldite GY 793 (containing active diluents), were modified with 5, 10, or 15 wt.% of 9-(2,3-epoxypropyl)carbazole, or 5(9-carbazolyl)methyl-1,3-oxothiolane-2-thione, or with their 3,6-dichloro- or 3,6-dibromo-derivatives to prepare homogeneous compositions that were crosslinked with isophorone diamine. Unique materials were obtained. Fluorescence spectrophotometry of the spin-coats (less than or equal to300 mum thick) made of the modified resins, gave spectra typical of isolated carbazole molecules (emission max. at 348 and 365 nm) and a few times as intensive as those of poly(9-vinylcarbazole). The 3,6-derivatives shifted the maxima of photoluminescence. Modification kept the original resin strength, hardness and thermal stability unaffected, reduced slightly water gain and flammability (O-2 index) (except for the 3,6-derivatives as modifiers), provided high adhesion to various substrates and a good thin-film formability; and made application for LED construction possible.