Toda Kogyo Corporation

Dic-hercules Chemicals, Inc.

Canon Kabushiki Kaisha

Unitika Ltd.

Toshiyuki Hakata

Tomoko Okita

Shigeru Takaragi

Kazuo Fujioka

Tetsuro Toda

Hiroshi Akai

Masaaki Fukugauchi

Hiroomi Kakihara

Yushi Mikuriya

Yoshiaki Echigo

Nanao Horiishi

Yasuhiko Fujii

Seiichi Takahashi

Hiromitsu Misawa

Kazumi Yoshizaki

Kenji Okada

Eiichi Kurita

Tomoyuki Imai

Toshiki Matsui

Keiichi Asami

Hirofumi Kawasaki

Shinji Uemoto

Satoshi Hatakeyama

Tsutomu Sakaida

Souichiro Kishimoto

Tsuyoshi Ikeda

Atsushi Maeda

Ryoma Masui

Tsugumi Ikegaya

Tetsuya Hara

Keigo Goshiki

The present invention relates to a magnetic particle-containing water dispersion wherein the magnetic particles have a primary particle diameter of 5 to 15 nm and an average secondary particle diameter of 10 to 60 nm, and the water dispersion has a zeta potential of not more than &#x2212;20 mV when a pH value of the water dispersion lies within the range of 6 to 8, and further a surface of the respective magnetic particles is coated with a carboxyl group-containing polymer. The magnetic particle-containing water dispersion is produced by heating an aqueous solution in which the carboxyl group-containing polymer is dissolved, to a temperature of 90 to 100&#xb0; C. in a nitrogen atmosphere; adding a solution of a ferrous (II) salt and a ferric (III) salt and an alkali solution to the aqueous solution to react with each other at the same temperature; adding ethanol to the solution to obtain a precipitate; and removing a supernatant liquid from the solution, and then dispersing the precipitate in water and subjecting the resulting dispersion to dialysis. The magnetic particle-containing water dispersion is useful as a magnetic particle-containing water dispersion capable of producing magnetic particle-containing drugs for diagnosis and therapies which can exhibit a uniform functionality, with a good reproducibility.

Magnetic iron oxide fine particles, and magnetic particle-containing water dispersion and process for producing the same

Disclosed is a paving resin composition which comprises a thermoplastic resin in small lumps, containing 30 to 70% by weight of an ethylene-vinyl acetate copolymer having a vinyl acetate content of 20 to 45% by weight and a melting temperature of 40 to 100&#xb0; C. The paving resin composition of the present invention is melted within a short time, excellent in wettability and adhesion property to aggregates, and capable of providing a paved face excellent in durability free from problems of deformation during summer and cracking during winter. Moreover, the paving resin composition of the present invention can be thrown directly to a mixer without being passed through a measurement apparatus and accordingly, washing work of the measurement apparatus or pipes is made unnecessary and the workability is thus significantly increased.

Paving resin composition, paving asphalt composition, and method for producing paving asphalt composition

There are provided a pharmaceutical raw material capable of exhibiting a uniform functionality and producing magnetic particle-containing drugs for diagnosis and medical treatments with a high reproducibility. The pharmaceutical raw material comprises a monodisperse colloid sterile aqueous solution of magnetic iron oxide fine particles having an average particle diameter of 5 to 30 nm, a saturation magnetization of 50 to 90 Am/kg and a coercive force of 0.1 to 1.6 kA/m. The pharmaceutical raw material can be produced by forming magnetic iron oxide fine particles in the form of a colloid aqueous solution, purifying the resultant colloid aqueous solution of superparamagnetic iron oxide particles by water-washing and removing water-soluble salts by-produced upon the reaction from the reaction solution by an ordinary method, and replacing a dispersing medium of the purified colloid aqueous solution with ultrapure water.

Pharmaceutical raw material

A magnetic carrier exhibiting excellent durability against mechanical impact as exerted by vibration and capable of exhibiting a stable charging performance in electrophotography is provided. The magnetic carrier is formed through a process including steps of: surface treating inorganic compound particles with a lipophilizing agent having a functional group (A) selected from epoxy group, amino group, mercapto group, organic acid group, ester group, ketone group, halogenated alkyl group and aldehyde group; forming composite particles from the surface-treated inorganic compound particles and a binder resin; and then surface-coating the composite particles with a coupling agent having a functional group (B) different from the functional group (A) of the lipophilizing agent and selected from epoxy group, amino group and mercapto group, or with a coating resin having a functional group (C) different from the functional group (A) of the lipophilizing agent and selected from epoxy group, amino group, organic acid group, ester group, ketone group and halogenated alkyl group.

Magnetic carrier

Magnetic particles and magnetic carrier for electrophotographic developer

Porous composite particles contain 80 to 98% by weight of a filling material and 2 to 20% by weight of carbon, and have an average pore diameter of not more than 5 nm when measured with respect to pores existing in both the surface and inside portions thereof, an average particle size of 1 to 1,000 &mgr;m and a specific surface area of 45 to 200 m /g. These porous composite particles individually contain the filling material in as large an amount as possible, so they have not only a high catalytic but also a high adsorption ability, thereby exhibiting an excellent catalytic activity.

Porous composite particles and process for producing the same

Method for treating organohalogen compound-containing soil or ash

Magnetic particles of the present invention comprise:

An electrophotographic magnetic carrier of the present invention has an average particle diameter of 10 to 300 .mu.m and comprising a composite particle having a two-layered structure, comprises:

Electrophotographic magnetic carrier and process for producing the same

Spherical-like composite particles having an average particle size of 1 to 1,000 .mu.m, a volume resistivity of 10.sup.10 to 10.sup.13 .OMEGA.cm and a coercive force of 100 to 4,000 Oe, comprising:

Spherical-like composite particles and electrophotographic magnetic

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

The disclosure describes a magnetic carrier for electrophotography having a number-average particle diameter of 1 to 1000 .mu.m, and comprising ferromagnetic iron compound particles, non-magnetic metal oxide particles and a phenol-based resin as a binder resin, the total amount of said ferromagnetic iron compound particles and said non-magnetic metal oxide particles being 80 to 99 wt %, and the ratio of the number-average particle diameter of said non-magnetic metal oxide particles and the number-average particle diameter of said ferromagnetic iron compound particles being more than 1.0.

Magnetic carrier for electrophotography

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

Toshiyuki Hakata