Toshiba Tec Kabushiki Kaisha

Kabushiki Kaisha Toshiba

Other

Yasuhito Noda

Tsuyoshi Itou

Takayasu Aoki

Masahiro Ikuta

Takafumi Hara

Takashi Urabe

Motonari Udo

Kazuhisa Takeda

Satoshi Araki

Shuitsu Sato

Koji Imamiya

Noboru Furuyama

Asumi Matsumoto

Takahito Kabai

Taishi Takano

Tsuyoshi Ito

Yoshihito Shimada

Yuichi Hori

A reversibly allochroic toner contains a binder resin and a colorant. The colorant reversibly switches between first and second color states in response to temperature changes. The colorant exhibits a hysteresis in a temperature-color state curve thereof in which the following relationships are satisfied.Tr&#x3c;T&#x3c;T&#x3c;T&#x3c;T&#x3c;TgT&#x2264;50&#xb0; C.20&#xb0; C.&#x2264;Tr&#x2264;30&#xb0; C.

Reversibly allochroic toner, method of producing the same, toner cartridge, and image forming apparatus

Certain embodiments provide a marking apparatus, which marks on media that is reusable by recording and erasing decolorable material, comprising a scanner configured to read media to which a first mark representing the reuse times of media is attached; a determination section configured to determine whether or not the media is reusable according to a reading result of the first mark or a use state of the media; and a recording section configured to print a second mark different from the first mark on the media according to a determination result representing that the media cannot be reused.

Marking apparatus and decoloring apparatus

In accordance with one embodiment, a color erasing apparatus comprises a conveyance path, a color erasing section and a control section. The conveyance path conveys a sheet. The color erasing section erases the color of an image formed with color erasable recording agent serving as recording agent containing coloring agent the color of which can be erased by heating. The control section carries out a control, in a case where the image formed on the sheet is not an image formed with the color erasable recording agent, so that the sheet is not subjected to a color erasing processing by the color erasing section.

Color erasing apparatus, color erasing system and color erasing control method

A reversibly allochroic toner contains a binder resin and a colorant. The colorant reversibly switches between first and second color states in response to temperature changes. The colorant exhibits a hysteresis in a temperature-color state curve thereof in which the following relationships are satisfied.Tr&#x3c;T&#x3c;T&#x3c;T&#x3c;T&#x3c;TgT&#x2266;50&#xb0; C.20&#xb0; C.&#x2266;Tr&#x2266;30&#xb0; C. where, Tis a temperature at which the colorant starts to change from the first color state to the second color state, Tis a temperature at which the colorant completely changes to the second color state, Tis a temperature at which the colorant starts to change from the second color state to the first color state, Tis a temperature at which the colorant completely changes to the first color state, and Tg is a glass transition temperature of the binder resin.

A toner set is used in a printing system that is capable of recycling a print medium and includes a first image forming portion which forms a toner image on the medium with a decolorable toner which is decolored by being heated at a temperature T(&#xb0; C.) or higher, a second image forming portion which forms a toner image on the medium with a non-decolorable toner and forms an image on the medium with at least one of the toners, and a decoloring apparatus provided with a heating portion which heats the medium on which a toner image is formed by the image forming apparatus at the temperature T(&#xb0; C.) or higher. When heated by the decoloring apparatus, the decolorable toner may be decolored without causing hot offset.

Toner set for printing system and printing system

According to one embodiment, there is provided an image forming apparatus which forms an decolorable image and an non-decolorable image by fixing a toner image including a decolorable toner and a toner image including a non-decolorable toner or a medium. The decolorable toner has a first peak of a loss tangent tan &#x3b4; at a temperature T, and the non-decolorable toner has a first peak of a loss tangent tan &#x3b4; at a temperature T. A difference between the temperature Tand the temperature Tis within 20&#xb0; C.

Image forming apparatus and image forming and decoloring system

According to one embodiment, a method of manufacturing an erasable toner includes washing toner particles including therein a coloring material that is erasable by heating and a binder resin to obtain a toner cake having the amount of water of 20% by weight to 60% by weight, and drying the toner cake at 40&#xb0; C. or more and at a temperature which is lower than the complete color erasing temperature of the toner particles by 30&#xb0; C. or more.

Method of manufacturing erasable toner

An electrophotographic toner contains an electron donating color former compound, an electron accepting color developing agent, and a binder resin, wherein a toluene insoluble content in the electrophotographic toner is 10% by mass or more and 40% by mass or less, and the toner is decolorized by heating.

Electrophotographic toner

An electrophotographic toner contains an electron donating color former compound, an electron accepting color developing agent, and a polyester binder resin having a weight average molecular weight Mw of 6000 or more and 25000 or less, and the toner is decolorized by heating.

An electrophotographic toner, which is decolorized by heating and a glossiness after decolorization of which is less than 10, comprising an electron donating color former compound, an electron accepting color developing agent, and a polyester binder resin.

The method for producing a developing agent according to the invention contains subjecting the toner material dispersion liquid to mechanical shearing to make the granular mixture into fine particles, thereby providing a dispersion liquid containing fine particles having a smaller particle diameter than a particle diameter of the granular mixture. The toner material dispersion liquid is subjected to mechanical shearing under a temperature of a glass transition point Tg of the binder resin or more and a pressure of 10 MPa or more, and the resulting dispersion liquid containing the fine particles is depressurized with two or more stages while maintaining the temperature of a glass transition point Tg of the binder resin or more and then cooled to a temperature of a glass transition point Tg of the binder resin or less.

Growing community of inventors

Mishima, Japan

Yasuhito Noda