| 摘要 |
PROBLEM TO BE SOLVED: To provide a retard roller composed of an inexpensive polishingless roller, stiking little paper powder, excellent in maintenability of a friction coefficient and capable of preventing a squeak in a low speed area, the retard roller for reducing an outer diameter difference while being the polishingless roller, and also provide a paper feeder using the retard roller. SOLUTION: A surface of the retard roller has the crest-like part 10 and a sea-like part 11 recessed more than the crest-like part 10. A crimp surface composed of the crest-like part 10 and the sea-like part 11 is composed of a fine recess-projection part 12. The ratio S1/S2 of the area S1 of the crest-like part 10 to the area S2 of the sea-like part 11 falls within a range of 0.25 to 0.55, and the height of the fine recess-projection part 12 falls within a range of 3 to 25μm. An outer diameter of the axis for pressing in a roller part is gradually reduced toward the opposite side from the press-in end to reduce the outer diameter difference.
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