# US 9,378,439 B2 · Image forming apparatus for printing an original image and an image indicating sheet reuse > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,378,439 B2 - Document ID: US9378439B2 - Status: Granted - Kind: B2 - Application number: 14/632,989 - Filed: 2015-02-26 - Published: 2015-10-15 - Granted: 2016-06-28 - Earliest claimed: 2014-04-10 - Assignees: Kabushiki Kaisha Toshiba; Toshiba Tec Kabushiki Kaisha - Applicants: Kabushiki Kaisha Toshiba; Toshiba Tec Kabushiki Kaisha - Inventors: Taizo Kimoto - Web page: https://patentgrep.com/patent/US9378439B2 ## CPC - G06K 15/1868: {for fitting to an output condition, e.g. paper colour or format} - G03G 15/6585: {by using non-standard toners, e.g. transparent toner, gloss adding devices} - G03G 2215/00797: Printing device, i.e. annotation - G06K: GRAPHICAL DATA READING (image or video recognition or understanding G06V); PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS - G03G: ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY ## Abstract According to an embodiment, an image forming apparatus includes an image forming unit and a controller. The image forming unit prints an original image and a specific image in a recording medium. In a case where it is determined that the recording medium is a reused recording medium, the controller controls the image forming unit to newly print the specific image at a position different from a print position of the previously-printed specific image. ## Claims ### Claim 1 An image forming apparatus comprising: an image acquisition unit which acquires an original image; an image forming unit which prints the acquired original image on a recording medium using a decolorable color material and prints a specific image on the recording medium using the decolorable color material, the specific image being substantially not visible to the human eye under standard light conditions; and a controller which determines whether the recording medium is a reused recording medium, arbitrarily sets a print position of the specific image on the recording medium, and controls the image forming unit to newly print the specific image at a position on the recording medium different from a print position of the previously-printed specific image when the recording medium is determined as the reused recording medium. ### Claim 2 (depends on 1) The image forming apparatus according to claim 1, further comprising: a mark read unit which detects a reuse mark on the recording medium indicating the number of reused times of the recording medium. ### Claim 3 (depends on 2) The image forming apparatus according to claim 2, wherein the controller determines whether the recording medium is the reused recording medium based on a detection result of the reuse mark of the mark read unit. ### Claim 4 (depends on 3) The image forming apparatus according to claim 3, wherein the controller controls the image forming unit to shift the print position of the specific image to a position different from the print position of the previously-printed specific image according to the number of reused times of the recording medium based on the detection result of the reuse mark of the mark read unit. ### Claim 5 (depends on 3) The image forming apparatus according to claim 3, further comprising: a reuse mark print unit which prints the reuse mark on the recording medium using a non-decolorable color material. ### Claim 6 (depends on 5) The image forming apparatus according to claim 5, wherein the reuse mark print unit prints the reuse mark on the recording medium each time that the image forming unit prints the original image and the specific image on the recording medium. ### Claim 7 (depends on 2) The image forming apparatus according to claim 2, wherein the controller controls the image forming unit to shift the print position of the specific image by a predetermined pitch each time that the recording medium is repeatedly reused. ### Claim 8 (depends on 7) The image forming apparatus according to claim 7, wherein the controller controls the image forming unit to shift the print position of the specific image within a predetermined range. ### Claim 9 (depends on 8) The image forming apparatus according to claim 8, wherein the controller sets the predetermined pitch based on an upper limit value of the number of reused times of the recording medium. ### Claim 10 (depends on 9) The image forming apparatus according to claim 9, wherein the controller sets the predetermined pitch with respect to each of a conveyance direction of the recording medium and a direction perpendicular to the conveyance direction. ### Claim 11 (depends on 10) The image forming apparatus according to claim 10, wherein the controller sets the predetermined range based on a size of the specific image. ### Claim 12 (depends on 11) The image forming apparatus according to claim 11, wherein the controller sets the predetermined range with respect to each of the conveyance direction of the recording medium to be conveyed and the direction perpendicular to the conveyance direction based on the size of the specific image. ### Claim 13 (depends on 2) The image forming apparatus according to claim 2, wherein the mark read unit detects the reused mark by reading both surfaces of the recording medium. ### Claim 14 (depends on 13) The image forming apparatus according to claim 13, wherein the controller determines whether the recording medium is the reused recording medium based on a detection result of the mark read unit for each recording medium.