JP2010014851A5 - - Google Patents

Claims (6)

A magnetic carrier having a coating layer on the surface in the resin composition of the magnetic core particles, the magnetic carrier and the magnetic carrier, and satisfies the following relational expression (A).
700 ≦ Et100 (mJ) ≦ 950 (A)
[Et100 (mJ) in the above formula (A) is a powder flowability analyzer equipped with a rotary blade, and the magnetic carrier is filled while rotating the peripheral speed of the outermost edge of the propeller blade at 100 mm / sec. Rotation obtained by vertically intruding into the magnetic carrier powder layer in the measured container, starting measurement from a position of 100 mm from the bottom surface of the powder layer, and entering the blade to a position of 10 mm from the bottom surface. Represents the sum of torque and vertical load. ] 2. The magnetic carrier according to claim 1, wherein the abundance ratio of particles having a circularity of 0.950 or less is 2.0% by number or less in a circularity distribution measured by a flow particle image analyzer. The magnetic carrier described. The magnetic carrier according to claim 1, wherein the coating layer contains fine particles, and the number average particle diameter of the fine particles is 80 nm or more and 300 nm or less. The magnetic carrier according to claim 3, wherein the fine particles contain silica fine particles produced by a sol-gel method. The magnetic carrier has the coating layer formed by fixing the fine particles on the surface of the particles obtained by coating the resin composition on the surface of the magnetic core particles using a coating processing apparatus,
The coating apparatus is provided with a rotating body in which a plurality of agitating members are disposed on the surface, and a casing having an inner periphery which is located at a gap with respect to the agitating member, said plurality of agitating members by a part of the agitating member of the resin composition and the a particles coated treated surface of the magnetic core particles particles, Ru sent in one direction in the axial direction of the rotating body, and feeding said plurality The particles obtained by coating the resin composition on the surface of the magnetic core particles by the other part of the stirring members of the stirring members and the fine particles are opposite to the one direction in the axial direction of the rotating body. passed back in a direction, returning, by the city is performed, the magnetic carrier according to claim 3 or 4, wherein that you fixing process. The resin composition comprises a copolymer having a monomer having a structure represented by the following formula (A1) and a macromonomer having a structure represented by the following formula (A2) or the following formula (A3) as a copolymerization component. magnetic carrier according to any one of claims 1 to 5, characterized in that a resin composition containing.