NOVELTY - A chlorinated naphthalenetetracarboxylic acid derivative is used as charge transport materials, exciton transport materials or emitter materials.    USE - Use of chlorinated naphthalenetetracarboxylic acid derivative (1) charge transport materials, exciton transport materials or emitter materials, as semiconductor material in organic electronics, particularly as n-semiconductors in organic FETs, as active material in organic photovoltaics, especially as charge transport material and/or exciton transport material in solar cells, and as exciton transport material in solar cells or excitonic solar cells; and for organic LED and organic solar cell (claimed).    ADVANTAGE - The use of chlorinated naphthalenetetracarboxylic acid derivative can provide high charge mobilities preferably e.g. of greater than or equal to 0.01 cm2-V-1s-1.    DETAILED DESCRIPTION - A chlorinated naphthalenetetracarboxylic acid derivative of formula (I) is used as charge transport materials, exciton transport materials or emitter materials.    R1-R4=Cl or H;    Y1=O or NRa;    Ra=H or organyl radical;    Y2=O or NRb;    Rb=H or organyl radical; and    Z1-Z4=O.    An INDEPENDENT CLAIM is included for a method for preparing a process for preparing compounds of formula (I-B) comprising:    (A) subjecting naphthalene-1,8:4,5-tetracarboxylic dianhydride to a reaction with an amine of formula RaNH2 and if appropriate an amine of the formula Rb-NH2 to obtain a compound of formula (D); and    (B) subjecting the compound to a chlorination by reaction with chlorine in the presence of iodine as a catalyst.    The chlorination of the compound (D) is brought about by reaction with chlorine in chlorosulfonic acid and in the presence of catalytic amounts of iodine.    R1, R4=Cl;    R2, R3=H; or    R1, R3=Cl; or    R2, R4=H; or    R1, R2, R3=Cl; or    R4=H; or    R1-R4=Cl; and    Ra, Rb=H or optionally substituted alkyl, cycloalkyl, bicycloalkyl, heterocycloalkyl, chlorinated aryl or chlorinated heteroaryl.