NOVELTY - Mono- and di-imide naphthalene compounds, are new.    USE - In a thin film semiconductor useful in transistor device, transparent organic transistor device (claimed) (e.g. organic field-effect transistor device), organic light-emitting device and photovoltaic device.    ADVANTAGE - The compound enhances oxidative stability and/or provides more positive reduction potential(s) of such compounds, as compared to unsubstituted polycyclic compounds of the prior art. The naphthalene mono- and di-imides can be functionalized at various core and imide position(s) with varying moieties for improved solubility and/or radical anion stability, while maintaining strong pi - pi interactions and/or intermolecular coupling. The cyano-substituted naphthalene imides have low reduction potentials, high solubility, and interesting optical characteristics.    DETAILED DESCRIPTION - Mono- and di-imide naphthalene compounds of formulae (I)-(IV), are new.    R1 and R2=1-20C alkyl, 2-20C alkenyl, 2-20C alkynyl, 3-10C cycloalkyl, 6-14C aryl, 3-14 membered cycloheteroalkyl, 5-14 membered heteroaryl (all optionally mono- to penta-substituted with Ra), 1-20C haloalkyl or H;    Ra=halo, CN, NO2, -N+(Rb)3, -S(O)mRb, -S(O)mORb, -C(O)Rb, -C(O)ORb, -(CH2CH2O)nCH2CH2OH or 1-20C haloalkyl;    Rb=H, 1-20C alkyl, 1-20C haloalkyl, 6-14C aryl, 1-20C alkyl-6-14C aryl or (1-20C haloalkyl)-6-14C aryl;    m=0-2;    n=1-10;    R3-R6=3-10C cycloalkyl, 6-14C aryl, 3-14C membered cycloheteroalkyl, 5-14 membered heteroaryl (all optionally mono- to penta-substituted with Ra), H, halo, -NO2, -N+(Rb)3, -S(O)2Rb, -S(O)2ORb, -C(O)Rb, -C(O)ORb, -(CH2CH2O)nCH2CH2OH or 1-20C haloalkyl;    R7 and R8=3-10C cycloalkyl, 6-14C aryl, 3-14 membered cycloheteroalkyl, 5-14 membered heteroaryl (all optionally mono- to penta-substituted with Ra), H, halo, -CN, -NO2, -N+(Rb)3, -S(O)2Rb, -S(O)2ORb, -C(O)Rb, -C(O)ORb, -(CH2CH2O)nCH2CH2OH or 1-20C haloalkyl.    Provided that at least one of R3-R6 is not H. INDEPENDENT CLAIMS are included for the following:    (1) a thin film semiconductor comprising the mono- and di-imide naphthalene compound;    (2) a composite comprising a substrate and the thin film semiconductor deposited on the substrate; and    (3) a transistor device and a transparent organic transistor device comprising the composite.