| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a developer conveyance roller and a developing device which contribute to the formation of an image having a desired print density stably over a long period of time even if mounted on an image forming device of a high-speed printing type, and an image forming device for forming an image having a desired print density stably over a long period of time. <P>SOLUTION: There are provided a developer conveyance roller 1 including a cylindrical foam elastic layer 3 in which the hardness ratio of an Asker F hardness (an Asker F hardness after the rotation testing/an Asker F hardness before the rotation testing) is 0.80 or more and a developing device and an image forming device having the developer conveyance roller 3. <Rotation Testing> In a state where a cylindrical roller made of stainless steel (SUS304) having an outer diameter of 20 mm and the developer conveyance roller are press-contacted in parallel so that the foam elastic layer is excavated by 2 mm, a developer conveyance roller is continuously rotated for 8 hours under the conditions of a temperature of 20°C and a rotational speed of 915 rpm. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
