TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Composition: The organic dye is of formula: D'-((A)n-(P')m)p-G (I).D'=triarylamino of formulae (II)-(VIII), preferably triarylamino (II);R1,R2=H or group (G1) chosen from 1-20C alkyl, linear or branched, optionally saturated 4-12C cycloalkyl optionally containing heteroatoms, 6-24C aryl, heteroaryl, 4-11C heterocyclyl, 1-20C alkoxy or aryloxy, or thioalkoxy or thioaryloxy (all optionally substituted), and trialkyl- or triaryl-silyl, or polyethylene oxide group of formula: R'-O-(-CH2-CH2-O)r-, preferably H;R'=H or 1-20C saturated, linear or branched alkyl;r=1-20;A=benzo-heterodiazolyl of formula (IX);R3,R4=H, group (G1), cyano, nitro or halo chosen from fluoro, chloro, bromo and iodo, preferably H;or R3+R4,R8+R9,R10+R11=optionally saturated 1-12C aryl optionally substituted by group (G1), dialkyl- or diaryl-amino, dialkyl- or diaryl-phosphino, cyano, nitro, or halo chosen from fluoro, chloro, bromo and iodo, and optionally containing heteroatoms chosen from oxygen, sulfur, nitrogen, silicon, phosphorus, selenium and boron;Z=heteroatom chosen from oxygen, sulfur, selenium and tellurium, or group of formula: X(R5), preferably sulfur;X=heteroatom chosen from nitrogen, phosphorus, arsenic and boron;R5=H, or 6-24C aryl, heteroaryl, 4-12C cycloalkyl or 4-11C heterocyclyl (all optionally substituted), 1-20C linear or branched, optionally saturated alkyl optionally containing heteroatoms, or group of formula: Y'(R6R7);Y',V'=carbon, silicon or germanium;R6,R7=group (G1);n=1-5, preferably 1;P'=(pi)-conjugated unit of formula (X), (XI) or (XII), preferably (pi)-conjugated unit (X);R8,R9=H, or group (G1), trialkyl-or triaryl-silyl, or halo chosen from fluoro, chloro, bromo and iodo, preferably H;R10,R11=4-12C cycloalkyl, 6-24C aryl, heteroaryl or 4-11C heterocyclyl (all optionally substituted), or linear or branched, optionally saturated 1-20C alkyl optionally containing heteroatoms;W'=heteroatom chosen from oxygen, sulfur, selenium and tellurium, preferably sulfur;m=1-7, preferably 1;p=1-3, preferably 1;G=anchoring group chosen from -COOH, -PO(OH)2 or -PO(OH)(R12), or carboxycyanovinylene of formula (XIII) or (XIV), preferably group (XIII) or (XIV);R12=linear or branched, optionally saturated 1-20C alkyl;andR13-R15=H, halo chosen from fluoro, chloro, bromo and iodo, or group chosen from 6-24C aryl, heteroaryl, 4-12C cycloalkyl and 4-11C heterocyclyl (all optionally substituted), linear or branched, optionally saturated 1-20C alkyl optionally containing heteroatoms, cyano and nitro, preferably H.