# US 10,455,120 B2 · Image forming apparatus, decoloring apparatus and image forming method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,455,120 B2 - Document ID: US10455120B2 - Status: Granted - Kind: B2 - Application number: 16/158,232 - Filed: 2018-10-11 - Published: 2019-02-07 - Granted: 2019-10-22 - Earliest claimed: 2014-09-22 - Assignees: Kabushiki Kaisha Toshiba; Toshiba Tec Kabushiki Kaisha - Applicants: Kabushiki Kaisha Toshiba; Toshiba Tec Kabushiki Kaisha - Inventors: Masanaka Mizuno - Web page: https://patentgrep.com/patent/US10455120B2 ## CPC - H04N 1/60: Colour correction or control {(H04N1/54 takes precedence)} - H04N 1/4433: {to an apparatus, part of an apparatus or an apparatus function} - H04N 2201/0094: Multifunctional device, i.e. a device capable of all of reading, reproducing, copying, facsimile transception, file transception - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract In one embodiment, an image forming apparatus forms an image on a recording medium using a plurality of decolorable coloring materials having different decoloring conditions. Further, the image forming apparatus forms a mark relating to authority information indicating authority capable of decoloring one of the plurality of decolorable coloring materials for each of the decolorable coloring materials on the recording medium. Further, in another embodiment, a decoloring apparatus grasps the authority information, and decolors the image of the decolorable coloring material, in accordance with the grasped authority information. ## Claims ### Claim 1 An image forming apparatus comprising: a conveyance device configured to convey a sheet; a first image forming unit configured to form a first image using a non-decolorable toner; a second image forming unit configured to form a second image using a decolorable toner that is decolored at and above a decoloring temperature; a transfer device configured to transfer the first and second images to the sheet conveyed by the conveyance device; and a processor configured to control the first and the second image forming unit and the transfer device such that the second image formed by the decolorable toner is superposed on at least a part of the first image formed by the non-decolorable toner. ### Claim 2 (depends on 1) The image forming apparatus according to claim 1, wherein the transfer device comprises: a transfer belt on which the first image is formed and the second image is formed after the first image is formed, and a transfer roller configured to transfer the first and second images to the sheet conveyed by the conveyance device. ### Claim 3 (depends on 2) The image forming apparatus according to claim 2, further comprising: a heating device configured to fix the first and second images transferred to the sheet by the transfer device by heating the first and second images to a fixing temperature lower than the decoloring temperature, and decolor the second image transferred to the sheet by the transfer device by heating the second image to the decoloring temperature. ### Claim 4 (depends on 1) The image forming apparatus according to claim 1, wherein the second image forming unit forms a solid image as the second image by using the decolorable toner. ### Claim 5 (depends on 1) The image forming apparatus according to claim 1, wherein the second image forming unit installed in the image forming apparatus is interchangeable with a third image forming unit, and the third image forming unit forms the second image using another decolorable toner that is decolored at or above a decoloring temperature different from the decoloring temperature of the decolorable toner used by the second image forming unit. ### Claim 6 (depends on 1) The image forming apparatus according to claim 1, wherein the second image forming unit forms the second image using a plurality of decolorable toners, and each of the decolorable toners has a decoloring temperature range that starts at different temperatures. ### Claim 7 (depends on 6) The image forming apparatus according to claim 6, further comprising: a user interface configured to receive a first operation to select a decolorable toner used to form the second image from the plurality of decolorable toners. ### Claim 8 (depends on 7) The image forming apparatus according to claim 7, wherein the user interface has a display controlled to display one or more available decolorable toners among the plurality of decolorable toners. ### Claim 9 (depends on 8) The image forming apparatus according to claim 8, wherein the user interface is configured to receive a second operation to determine an image area of the sheet on which the second image is formed. ### Claim 10 (depends on 9) The image forming apparatus according to claim 9, wherein the processor is configured to control the first and second image forming unit and the transfer device based on the first and the second operation received by the user interface. ### Claim 11 An image forming method carried out by an image forming apparatus, the image forming method comprising: conveying a sheet with a conveyance device; forming a first image using a non-decolorable toner with a first image forming unit; forming a second image using a decolorable toner that is decolored at and above a decoloring temperature with a second image forming unit; and transferring, with a transfer device, the first and second images to the sheet such that the second image formed by the decolorable toner is superposed on at least a part of the first image formed by the non-decolorable toner. ### Claim 12 (depends on 11) The image forming method according to claim 11, wherein the second image is formed on a transfer belt after the first image is formed on the transfer belt, and the first and second images are transferred to the sheet by a transfer roller. ### Claim 13 (depends on 12) The image forming method according to claim 12, further comprising: fixing the first and second images transferred to the sheet by heating the first and second images to a fixing temperature lower than the decoloring temperature, and decoloring the second image transferred to the sheet by heating the second image to the decoloring temperature. ### Claim 14 (depends on 11) The image forming method according to claim 11, wherein a solid image is formed as the second image by using the decolorable toner. ### Claim 15 (depends on 11) The image forming method according to claim 11, wherein the second image forming unit installed in the image forming apparatus is interchangeable with a third image forming unit, and the third image forming unit forms the second image using another decolorable toner that is decolored at or above a decoloring temperature different from the decoloring temperature of the decolorable toner used by the second image forming unit. ### Claim 16 (depends on 11) The image forming method according to claim 11, wherein the second image is formed using a plurality of decolorable toners, and each of the decolorable toners has a decoloring temperature range that starts at different temperatures. ### Claim 17 (depends on 16) The image forming method according to claim 16, further comprising: receiving by a user interface a first operation to select a decolorable toner used to form the second image from the plurality of decolorable toners. ### Claim 18 (depends on 17) The image forming method according to claim 17, further comprising: displaying on a display of the user interface one or more available decolorable toners among the plurality of decolorable toners. ### Claim 19 (depends on 18) The image forming method according to claim 18, further comprising: receiving by the user interface a second operation to determine an image area of the sheet on which the second image is formed. ### Claim 20 (depends on 19) The image forming method according to claim 19, wherein the first and second image forming unit and the transfer device are controlled based on the first and the second operation received by the user interface.