TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Compound: The semiconductor layer contains titanium oxide or zinc oxide.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation: No general preparation given. Preferred Definitions:    X=carboxy, hydroxy, sulfonic acid group, or phosphonic acid group;    D'=organic group of formula: N(-Ar1)(-Ar2)-Ar3 or N(-Ar1)(-Ar2)-;    Ar1,Ar2=alkyl or aryl (both optionally substituted), or heterocyclyl;    Ar3=arylene or bivalent heterocyclyl (both optionally substituted);    Z=group of formula (i);    R2,R3=H, optionally substituted alkyl, or alkoxy;    R2+R3=ring;    Y'=oxygen, sulfur, or NR'a;and    R'a=H, or alkyl or aryl (both optionally substituted).    SPECIFIC COMPOUNDS - 2-(3-Cyano-4-(5-(4-(diphenylamino)phenyl)thiophen-2-yl)-2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)acetic acid of formula (IA), 2-(3-(7-(4-(bis(4-(hexyloxy)phenyl)amino)phenyl)-2H,3H-thieno(3,4-b)(1,4)dioxin-5-yl)-4-isocyano-2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)acetic acid, 2-(3-(7-(7-(7-(4-(bis(4-(hexyloxy)phenyl)amino)phenyl)-2H,3H-thieno(3,4-b)(1,4)dioxin-5-yl)-2H,3H-thieno(3,4-b)(1,4)dioxin-5-yl)-2H,3H-thieno(3,4-b)(1,4)dioxin-5-yl)-4-isocyano-2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)acetic acid, and 2-(3-(5-(bis(4-(2-phenylpropan-2-yl)phenyl)amino)thiophen-2-yl)-4-cyano-2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)acetic acid are disclosed as compound (I).    EXAMPLE - (In g) 2-chloro-3-cyano-maleimide (2) was dissolved in acetonitrile (100 ml), and 4-(thiophen-2-yl)triphenylamine (4.19) was added and reacted at room temperature. Water (600 ml) was added and the precipitated crystal was filter-separated and washed with warm water several times. 4-(5-(4-(Diphenylamino)phenyl)thiophen-2-yl)-2,5-dioxo-2,5-dihydro-1H-pyrrole-3-carbonitrile (3.15) was obtained by carrying out heat-stirring washing in ethanol (100 ml) with a yield of 55%. The compound (2) and t-butyl bromoacetate (1.31) were dissolved in acetonitrile (80 ml), and potassium carbonate (0.62) was added and stirred at 80 degrees C for 2 hours. The reaction mixture was poured into ice water (1000 ml) after cooling, and precipitated crystal was filter-separated. The crystal was washed with hexane/ethyl acetate (110 ml), to obtain t-butyl 2-(3-cyano-4-(5-(4-(diphenylamino)phenyl)thiophen-2-yl)-2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)acetate (1.2) with a yield of 48%. The obtained compound (1) was dissolved in acetonitrile (40 ml), and p-toluenesulfonic acid monohydrate (0.406) was added and heat-refluxed for 1 hour. The reaction mixture was poured into ice water (400 ml) after cooling, and the precipitated crystal was filter-separated and washed with water and then with warm water to obtain 2-(3-cyano-4-(5-(4-(diphenylamino)phenyl)thiophen-2-yl)-2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)acetic acid (0.39) with a yield of 44%. The compound had lambda max in acetonitrile of 563 nm.