Toda Kogyo Corporation

Unitika Ltd.

Toda Gokyo Corporation

Souichiro Kishimoto

Tetsuro Toda

Yoshiaki Echigo

Tsutomu Sakaida

Shigeru Takaragi

Eiichi Kurita

Toshiyuki Hakata

Keiichi Asami

Kazuo Fujioka

Hiromitsu Misawa

Koso Aoki

Yoji Okano

Kaori Kinoshita

Minoru Kozawa

Yasuhiko Fujii

Shinji Uemoto

Shigenori Harada

Nobuya Shimo

Muneyoshi Sakamoto

Katsuji Iwami

Kunihiro Ichimura

Naoki Uchida

Haruki Kurokawa

Kazushi Takama

Ryo Iwai

Masahide Ueda

Youzi Okano

Kazuya Fujita

A solid recovery material for carbon dioxide includes from 1% by weight to 99% by weight of sodium ferrite and from 1% by weight to 99% by weight of porous material. The material has an average particle diameter of 1 mm to 10 mm, and having a specific surface area of 5 m/g to 1500 m/g. An axial ratio of an average major axis diameter to an average minor axis diameter of primary particles of the sodium ferrite is from 1 to 2.

Solid recovery material for carbon dioxide and method for producing same

The sodium ferrite particle powder according to the present invention is characterized in that at least one metal or more selected from the metal group consisting of silicon, aluminum, titanium, manganese, cobalt, nickel, magnesium, copper and zinc is contained in an amount of 0.05 to 20% by weight in terms of the oxide, and the molar ratio of Na/Fe is 0.75 to 1.25.

Sodium ferrite particle powder and production method thereof

The present invention relates to a magnetic carrier for an electrophotographic developer comprising spherical composite core particles comprising at least ferromagnetic iron oxide fine particles and a cured phenol resin, and having an average particle diameter of 20 to 60 &#x3bc;m, the magnetic carrier for an electrophotographic developer satisfying the formula (1): &#x3c3;&#x2212;&#x3c3;=&#x2212;2 to 0 wherein &#x3c3;represents a saturation magnetization (Am/kg) of the carrier particles having a particle diameter in the vicinity of the average particle diameter of the magnetic carrier for an electrophotographic developer; and &#x3c3;represents a saturation magnetization (Am/kg) of the carrier particles having a particle diameter of less than 20 &#x3bc;m, and a two-component system developer using the magnetic carrier. The two-component system developer of the present invention includes a magnetic carrier used for an electrophotographic developer which can exhibit a good durability, is free from occurrence of carrier adhesion, and can maintain a high quality of images produced for a long period of time, and comprises the magnetic carrier for an electrophotographic developer and a toner.

Magnetic carrier for electrophotographic developer and process for producing the same, and two-component system developer

The present invention relates to a magnetic carrier for an electrophotographic developer comprising spherical magnetic composite particles comprising a phenol resin as a binder and ferromagnetic iron oxide particles bonded to each other through the phenol resin, wherein the spherical magnetic composite particles have a ten-point mean roughness Rz of 0.3 to 2.0 &#x3bc;m. The magnetic carrier for an electrophotographic developer according to the present invention exhibits an excellent durability against peeling-off and abrasion of coating resins formed thereon and a high stability to mechanical stress exerted onto the carrier, is free from occurrence of spent toner, can be stably held over a long period of time without occurrence of fogging and unevenness in density of toner images, and can keep high-quality images with an excellent gradation for a long period of time.

The present invention provides a magnetic carrier for an electrophotographic developer which has an excellent durability and a stable charging property and is free from occurrence of spent toner thereonto, and a two-component system developer comprising the magnetic carrier for an electrophotographic developer and a toner. The present invention relates to a core material of a magnetic carrier for an electrophotographic developer comprising spherical composite particles comprising at least ferromagnetic iron oxide fine particles and a cured phenol resin and having an average particle diameter of 1 to 100 &#x3bc;m, a resin index of the spherical composite particles being within the range of 35 to 80%, and a magnetic carrier obtained by coating a surface of respective particles of the magnetic carrier core material with a resin.

Core material of magnetic carrier for electrophotographic developer and process for producing the same, magnetic carrier for electrophotographic developer, and two-component system developer

The present invention provides magnetic iron oxide particles having a high bonding property to a resin as well as a magnetic carrier for electrophotographic developers which is improved in durability by enhancing adhesion between a magnetic carrier core material and a coating resin. The magnetic iron oxide particles of the present invention are magnetic iron oxide particles having an average particle diameter of 0.5 to 30 &#x3bc;m onto which a plurality of granules are bonded, and the magnetic carrier for electrophotographic developers according to the present invention is a magnetic carrier for electrophotographic developers which comprises spherical magnetic composite particles produced by dispersing magnetic iron oxide particles in a binder resin in which the magnetic iron oxide particles comprise at least the above magnetic iron oxide particles having an average particle diameter of 0.5 to 30 &#x3bc;m onto which the plurality of granules are bonded.

Magnetic iron oxide particles, magnetic carrier for electrophotographic developers and process for producing the same, and two-component system developer

Black magnetic iron oxide particles having an average particle diameter of 0.05 to 2.0 &#x3bc;m and an electric resistance value at an applied voltage of 100 V of not less than 1&#xd7;10&#x3a9;&#xb7;cm. Also a magnetic carrier for electrophotographic developer having spherical magnetic composite particles obtained by dispersing black magnetic iron oxide particles in a binder resin. The magnetic carrier has an electric resistance value Rat an applied voltage of 100 V of 1&#xd7;10to 1&#xd7;10&#x3a9;&#xb7;cm, and an electric resistance value Rat an applied voltage of 300 V which satisfies the relationship represented by the formula:0.1&#x2266;300/100&#x2266;1.

Black magnetic iron oxide particles, magnetic carrier for electrophotographic developer and two-component developer

The present invention relates to magnetic composite particles comprising at least magnetic fine particles and a bio-based polymer, wherein the magnetic composite particles have an average particle diameter of 10 to 100 &#x3bc;m, and a content of the magnetic fine particles in the magnetic composite particles is 50 to 99.9% by weight; a magnetic carrier; and a developer. The magnetic composite particles, magnetic carrier and developer according to the present invention are effective for reduction of environmental burden such as saving of underground sources and prevention of global warming, have a high safety for human bodies and a high durability, and are capable of forming developed images with a high quality.

Magnetic composite particles, magnetic carrier and developer

The present invention relates to a magnetic carrier for an electrophotographic developer comprising spherical composite particles comprising spherical composite core particles comprising at least ferromagnetic iron oxide fine particles and a cured phenol resin and having an average particle diameter of 1 to 100 &#x3bc;m, and a melamine resin coating layer formed on the respective core particles, wherein a ratio of Rto R(R/R) in which Ris an electric resistance value as measured when applying a voltage of 100 V to the magnetic carrier; and Ris an electric resistance value as measured when applying a voltage of 300 V to the magnetic carrier, is controlled to lie within the range of 1 to 50. The magnetic carrier according to the present invention is capable of maintaining an adequate electric resistance value upon development, providing images having an excellent image quality, exhibiting a good durability, obtaining a good reproducibility of uniform solid image portions having a high image density, and keeping high quality images having an excellent gradation for a long period of time.

Disclosed herein is iron oxide particles comprising:

Iron oxide particles and process for producing the same

The disclosure describes a surface reforming agent comprising a cone-type calix �4! resorcinarene compound represented by the formula (I): ##STR1## wherein R is an alkyl group having 3 to 18 carbon atoms, an alkenyl group having 3 to 18 carbon atoms, an aralkyl group having 3 to 18 carbon atoms or a substituted or non-substituted aryl group; R.sup.1 is a hydrogen atom, a carboxyalkyl group in which the alkyl group has 1 to 3 carbon atoms, or a hydroxyalkyl group having 2 to 4 carbon atoms.

Surface reforming agent, surface reforming method and cone-type calix �4! r

The disclosure describes coated granular magnetite particles comprising:

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Hiroshima, Japan

Eiichi Kurita