| 摘要 |
<p>An ester polymer composed of solely the following repeating units (I): -(-W-X-O-CO-)- or both of the repeating units (I) and (II) and having a reduced viscosity [θsp/C] of 0.2-10.0 dl/g as measured with a solution thereof in methylene chloride at a concentration of 0.5 g/dl at 20 °C; a process for producing the ester polymer by the reaction of a dihydric phenol (III): HO-X-OH or a mixture of dihydric phenols (III) and (IV) with a carbonate-forming compound or a dibasic acid; and an electrophotographic photoreceptor comprising a photosensitive layer provided on a conductive support, wherein the ester polymer is used as a charge transport substance or a binder resin in the photosensitive layer. In said formulae, W represents -O- or a single bond; X represents a divalent group derived from a dihydric phenol containing a hydrazine structure; R?25 and R26¿ represent each halogen, alkyl, cycloalkyl or aryl; m and n represents each an integer of 0 to 4; and Y represents a single bond, -O-, -S-, -SO-, -SO¿2?-, -CR?27R28¿-, 1,1-cycloalkylene or a α,φ-alkylene.</p> |
