Toda Kogyo Corporation

Agency of Industrial Science and Technology

Unitika Ltd.

Dai-ichi High Frequency Co., Ltd.

Shigeru Takaragi

Yasuhiko Fujii

Tetsuro Toda

Minoru Ohsugi

Toshiyuki Hakata

Yasushi Nishio

Nanao Horiishi

Kazuo Fujioka

Tomohisa Moriya

Yosuke Koyama

Yoshiaki Echigo

Masao Kato

Eiichi Kurita

Hachiro Nakanishi

Keiichi Asami

Osamu Sasaki

Kotaro Hirayama

Hiroshi Yamamoto

Hiro Matsuda

Shuji Okada

Masaharu Abe

Souichiro Kishimoto

Tsutomu Sakaida

Kyoichi Nakamura

Masanori Terasaki

Takahiro Araki

Takayoshi Ohara

Tatsuya Ishida

Kazuhisa Kanefuji

Yasuhiko Fuji

The present invention relates to ferrite particles for bonded magnet, having a volume-average particle diameter of 2.1 to 2.7 &#x3bc;m and a particle diameter &#xd7;90 of 4.3 to 5.4 &#x3bc;m wherein the &#xd7;90 represents a particle diameter at which a cumulative percentage of particles under sieve (undersize particles) based on a volume thereof is 90%, when determined from a particle size distribution thereof measured by using a laser diffraction type particle size distribution measuring apparatus.

Ferrite particles for bonded magnet, resin composition for bonded magnet and molded products using the same

The present invention relates to ferrite particles for bonded magnets and a resin composition for bonded magnets which exhibit a good moldability, in particular, a good mechanical strength even when rapidly quenched upon injection-cooling, and is capable of producing a bonded magnet molded product having excellent magnetic properties, as well as a bonded magnet molded product such as a magnet roll using the ferrite particles and the resin composition. There are provided ferrite particles for bonded magnets which comprise phosphorus adsorbed and/or incorporated in ferrite, in which a content of the phosphorus in the ferrite is 120 to 5000 mg/kg (0.012 to 0.50% by weight) in terms of P; a resin composition for bonded magnets; and a magnet roll.

Ferrite particles for bonded magnets, resin composition for bonded magnets, and molded product comprising the same

The present invention relates to ferrite particles for bonded magnet, having a volume-average particle diameter of 2.1 to 2.7 &#x3bc;m and a particle diameter x90 of 4.3 to 5.4 &#x3bc;m wherein the x90 represents a particle diameter at which a cumulative percentage of particles under sieve (undersize particles) based on a volume thereof is 90%, when determined from a particle size distribution thereof measured by using a laser diffraction type particle size distribution measuring apparatus.

Resin composition for bonded magnet and bonded magnet using the same

The disclosure described a material having a damping property, comprising 100 parts by weight of a binder resin composed of 85 to 99% by weight of at least one base resin selected from the group consisting of polypropylenes, polystyrenes, acrylonitrile-butadiene-styrene copolymers, polycarbonates, polyphenylene ethers and modified polyphenylene ethers and 1 to 15% by weight of styrene-isoprene-styrene block copolymer, and 1 to 20 parts by weight of iron compound particles.

Material having a damping property and masterbatch pellets thereof

An injection-molding device including an injection machine, a mold unit connected to the injection machine having separable molds defining a cavity for forming a molded product, and chucks next to the mold unit for removing a molded product from the mold. The molded product is initially coolied in the mold cavity then again cooled after removal from the mold unit. Plural chucks are advanced into and retreated from a region defined by the open molds, the chucks being a pair of blocks grasping the surface of the molded product, each block having a circulating path through which a heating medium is passed to cool the grasping surface. The injection-molding apparatus produces articles having high dimensional accuracy, for example, electronic parts such as a magnet roll or the like.

Injection-molding apparatus and method of injection-molding

Material having a damping property and masterbatch pellets therefor

Disclosed are herein spherical magnetic particles comprising magnetic particles, a thermosetting resin and carbon which is derived from the thermosetting resin by carbonizing at least a part of the thermosetting resin, and having an average particle diameter of 1 to 1000 .mu.m.

Spherical magnetic composite particles

Disclosed herein are polydiphenyldiacetylenes having the following repeating unit (III): ##STR1## (wherein R.sup.1 denotes a hydrogen atom or a methoxy group; R.sup.2 denotes a hydrogen atom, a methoxy group or a methylamino group; R.sup.3 denotes a hydrogen atom or a trifluoromethyl group; and R.sup.4 denotes a hydrogen atom or a trifluoromethyl group; provided that R.sup.1 is not a hydrogen atom when R.sup.2 is hydrogen atom, and R.sup.3 is not a hydrogen atom when R.sup.4 is hydrogen atom).

Polydiphenyldiacetylenes

Disclosed herein is a method for bonding a resin part, which comprises disposing a magnetic complex composed of a resin and magnetic particles as a heating-medium at the resin parts to be bonded, and applying an alternating magnetic field to the heating-medium by using a magnetic field generating means composed of an electromagnetic core and an exciting coil, thereby making said heating-medium generate heat for fuse-bonding said resins.

Resin-bonding method

Disclosed herein are magnetic particles used for an electrostatic latent image developer comprising composite particles containing from more than 80% by weight to not more than 99% by weight of fine ferromagnetic particles and a cured phenol resin, and having a number-average particle diameter of from not less than 1 .mu.m to less than 10 .mu.m and an apparent density of not greater than 1.5 g/cm.sup.3.

Magnetic particles used for electrostatic latent image developer and

Disclosed herein are composite carrier particles for electrophotography comprising 80 to 99% by weight of ferromagnetic fine particles and a phenol resin, and having a number-average particle diameter of 10 to 1,000 .mu.m, a bulk density of not more than 2.0 g /cm.sup.3, and a curved surface configuration, and a process for producing the same.

Composite carrier particles for electrophotography and process for

Growing community of inventors

Hiroshima, Japan

Shigeru Takaragi