Abstract: According to one embodiment, a method for erasing an image includes erasing an image formed using a toner containing at least a binder resin, an electron donating color developable agent, and an electron accepting color developing agent by heating for 10 seconds or less. A color difference ?E between a region where the image is erased and a paper is 5 or less.

Abstract: An image forming apparatus includes a first image forming unit configured to form a first image to be transferred to a sheet with a non-decolorizable material, and a second image forming unit configured to form a second image to be transferred to the sheet with a decolorizable material. At least a part of the second image transferred to the sheet is formed on the first image transferred to the sheet.

Abstract: 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.

Abstract: 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 Te (° 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 Te (° C.) or higher. When heated by the decoloring apparatus, the decolorable toner may be decolored without causing hot offset.

Abstract: 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<TL2<TL1<TH1<TH2<Tg TH2?50° C. 20° C.?Tr?30° C. where, TH1 is a temperature at which the colorant starts to change from the first color state to the second color state, TH2 is a temperature at which the colorant completely changes to the second color state, TL1 is a temperature at which the colorant starts to change from the second color state to the first color state, TL2 is a temperature at which the colorant completely changes to the first color state, and Tg is a glass transition temperature of the binder resin.

Abstract: 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 Te (° 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 Te (° C.) or higher. When heated by the decoloring apparatus, the decolorable toner may be decolored without causing hot offset.

Abstract: 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 ? at a temperature TE1, and the non-decolorable toner has a first peak of a loss tangent tan ? at a temperature TU1. A difference between the temperature TE1 and the temperature TU1 is within 20° C.

Abstract: An image forming apparatus includes a first image forming unit and a second image forming unit. The first image forming unit is configured to form a first image portion to be transferred to a sheet with a first decolorizable material that is decolorized at a first temperature. The second image forming unit is configured to form a second image portion to be transferred to the sheet with a second decolorizable material that has a color different from the first decolorizable material and that is decolorized at a second temperature that is higher than the first temperature.

Abstract: 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° C. or more and at a temperature which is lower than the complete color erasing temperature of the toner particles by 30° C. or more.

Abstract: 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.

Abstract: 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.

Abstract: An electrophotographic toner contains an electron donating color developable agent, an electron accepting color developing agent, and a polyester resin binder which is a polyester resin obtained by polycondensation of a carboxylic acid component and an alcohol component and has a crosslinked structure formed of a crosslinking component including at least either one of a trivalent or higher valent carboxylic acid and a trihydric or higher hydric alcohol, and is decolorized by heating.

Abstract: Disclosed is a decolorizable electrophotographic toner, including: a binder resin; and a colorant which contains at least a color developable compound and a color developing agent and is covered with an outer shell so as to have a capsule structure, wherein the number ratio of particles having an equivalent circle diameter of 0.6 ?m or more and 2.5 ?m or less of the toner when measured using a flow particle image analyzer after the toner is dispersed in an aqueous medium at a ratio of 0.08% by weight and the resulting dispersion is subjected to a stirring treatment in which stirring is performed at 5000 rpm for 30 minutes using a homogenizer (T-25 digital ULTRA-TURRAX (manufactured by IKA Japan K.K., provided with a shaft generator S25N-10G)) is 30% by number or less.

Abstract: According to one embodiment, a method of manufacturing a color erasable developing agent including preparing a dispersion containing a fine particle containing a leuco dye and a developer, a fine particle containing a color erasing agent, a toner binder resin fine particle and a medium, aggregating the fine particles in the medium, and heat fusing the aggregate to form a toner particle is provided.

Abstract: According to one embodiment, a method for erasing an image includes erasing an image formed using a toner containing at least a binder resin, an electron donating color developable agent, and an electron accepting color developing agent by heating for 10 seconds or less. A color difference ?E between a region where the image is erased and a paper is 5 or less.

Abstract: An image forming apparatus includes a first image forming unit configured to form a first image to be transferred to a sheet with a non-decolorizable material, and a second image forming unit configured to form a second image to be transferred to the sheet with a decolorizable material. At least a part of the second image transferred to the sheet is formed on the first image transferred to the sheet.

Abstract: An image forming apparatus includes a first image forming unit and a second image forming unit. The first image forming unit is configured to form a first image portion to be transferred to a sheet with a first decolorizable material that is decolorized at a first temperature. The second image forming unit is configured to form a second image portion to be transferred to the sheet with a second decolorizable material that has a color different from the first decolorizable material and that is decolorized at a second temperature that is higher than the first temperature.

Abstract: Disclosed is a process for production of a decolorable toner, including: aggregating dispersed fine particles of a color material comprising at least a color-forming compound, a color-developing agent and a decoloring agent with dispersed fine particles comprising at least a binder resin comprising a polyester resin to form aggregates in an aqueous medium, adding a reactive polymer having an oxazoline group in to the aqueous medium, and fusing the aggregates in the aqueous medium. As a result, it becomes possible to produce a decolorable toner which suppresses the generation of fine powder due to the release of fine particles of an erasable color material from the toner.

Abstract: According to one embodiment, a decolorizable water-based inkjet ink includes a color material, a solvent, and a nonionic surfactant. The color material contains a color developable compound and a color developing agent, and the solvent contains water and a water-soluble organic solvent. The nonionic surfactant is contained in the ink in an amount of 5 wt % or more of the total amount of the solvent.

Abstract: According to one embodiment, an image forming apparatus includes a mode setting section configured to set an operation mode in a manner that the image forming apparatus is operated in an erasing mode if an erasing operation is instructed, a supplying section configured to supply a medium on which the image formation is completed, and which is set in an designated or specified receiving section, a decoloring section configured to decolor the color of the formed image by carrying the medium to a heating section that includes at least heating and decoloring function, and a return section configured to return the operation mode to a predetermined mode except for the erasing mode from the erasing mode, when the last medium on which the image formation is completed and which is set in the receiving section is decolored.