The invention relates to the use of compounds of formulae (I) and/or (II) as colorless IR absorbers wherein M is Ni, Pd, Pt, Au, Ir, Fe, Zn, W, Cu, Mo, In, Mn, Co, Mg, V, Cr or Ti, X1, X2 and X3 are each independently of the others sulfur or oxygen, R1, R2, R3, R4, R5 and R6 are each independently of the others hydrogen, NR7R8, unsubstituted or substituted C1-C18alkyl, C1-C18 alkyl wherein the alkylene chain is interrupted with oxygen, unsubstituted or substituted C1-C18alkenyl, unsubstituted or substituted aryl, unsubstituted or substituted arylalkyl or unsubstituted or substituted heteroarylalkyl, R2 and R8, each independently of the other, being unsubstituted or substituted C1-C18alkyl, unsubstituted or substituted aryl, unsubstituted or substituted arylalkyl or unsubstituted or substituted heteroarylalkyl, a further IR absorber optionally being added to the compounds of formulae (I) and (II). The invention relates also to novel dithiolene compounds of formulae (I) and (II) wherein X1 is oxygen and X2 and X3 are oxygen or sulfur. The invention relates furthermore to novel dithiolene compounds of formulae (I) and (II) wherein R1 to R6 arc NR7R8.