Development role with a development hole to support developers without tension through a regulatory element

摘要

A developing roller (3) used in a developing device (2) includes a magnet roller (3b) including a plurality of magnets (3a), and a developing sleeve (3c) provided outside of the magnet roller to carry and convey a developer while bearing the developer by a magnet force of the magnet roller. The surface of the developing sleeve is configured such that a transportation capacity of the developer in end portions of the developing sleeve which correspond to a vicinity of ends of the magnet roller is smaller than the transportation capacity of the developer in a central portion of the developing sleeve which corresponds to a central portion of the magnet roller. IMAGE