Abstract: During rolling with a rolling mill, which includes a sheet shape altering device capable of altering a mechanical sheet crown, while the sheet shape altering device is operated correspondingly with a target mechanical sheet crown set value during the dimensional alteration in rolling, the invention enables a stable sheet shape to be achieved, even when the mechanical sheet crown is altered to a large extent during rolling. Specifically, the target mechanical sheet crown set value, during the dimensional alteration in rolling, is previously set based on target mechanical sheet crown set values, before and after the dimensional alteration, prior to start of the dimensional alteration in rolling. The sheet shape altering device is then operated so that an actual mechanical sheet crown, during the dimensional alteration in rolling, is equal to the target mechanical sheet crown set value during the dimensional alteration in rolling.

Abstract: The present invention relates to a benzidine derivative represented by the general formula (1): ##STR1## wherein R.sup.1 to R.sup.6, m and n are as defined in the present specification. The benzidine derivative improves durability and heat resistance of a membrane containing the same while maintaining high hole transferring capability. Therefore, an electrophotosensitive material, which comprises a photosensitive layer containing the benzidine derivative, has high sensitivity and is superior in durability and heat resistance.

Abstract: The present invention provides an electrophotosensitive material having an improved sensitivity in comparison with a conventional one, obtained by combining a trinitrofluorenoneimine derivative represented by the formula (1): ##STR1## wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are the same or different and indicate a hydrogen atom, an alkyl group, an alkoxy group, an aryl group which may contain a substituent, an aralkyl group which may contain a substituent, or a halogen atom! as an electron transferring material with a prescribed electric charge generating material or hole transferring material.