| 摘要 |
PURPOSE:To enale to obtain a magnetic roll of high surface magnetic flux density, to enable to obtain clearness of a picture, and to enable to obtain the magnetic roll of low cost by a method wherein magnetic substance layers of the plural number being in layers in the radial direction are provided, and the magnetic characteristics of the magnetic substance layer at the outermost circumference is made higher than the magnetic characteristics of the magnetic substance layer at the inside. CONSTITUTION:A magnetic substance layer 4 is provided around a shaft 3, and moreover a magnetic substance layer 5 is provided at the outside thereof. The magnetic substance layer 4 is not performed with an orienting process, and the magnetic substance layer 5 is oriented in the radial direction. The magnetic characteristics differ according to the rate of the oriented layer (the magnetic substance layer 5) occupying in the magnetic layers of the whole, and a favorable result is represented when the rate thereof is 0.3-0.7 in general. The magnetic substance layer 4 is formed by molding a cylindrical substance according to a wrapping process of a sheet according to a calender process, an extruding process and an injection molding process of a resin composition dispersed with isotropically magnetic powder, for example, and the magnetic substance layer 5 is formed by performing a calender process, an extruding process and an injection molding process under the action of a magnetic field to the resin composition of magnetic powder having magnetic anisotropy, for example. The number of the magnetic substance layers is not limited to two. |
