# US 10,479,081 B2 · Printhead with flexible substrate > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,479,081 B2 - Document ID: US10479081B2 - Status: Granted - Kind: B2 - Application number: 15/748,844 - Filed: 2015-10-12 - Published: 2018-08-02 - Granted: 2019-11-19 - Earliest claimed: 2015-10-12 - Assignees: Hewlett-Packard Development Company, L.P. - Applicants: Hewlett-Packard Development Company, L.P. - Inventors: Silam J. Choy - Web page: https://patentgrep.com/patent/US10479081B2 ## CPC - B41J 2/155: for line printing - B41J 2/04541: {Specific driving circuit} - B41J 2/0458: {controlling heads based on heating elements forming bubbles} - B41J 2/04581: {controlling heads based on piezoelectric elements} - B41J 2/04585: {controlling heads based on thermal bent actuators} - B41J 2002/14491: {Electrical connection} - B41J 2202/11: characterised by specific geometrical characteristics - B41J: TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS ## Abstract In one example in accordance with the present disclosure a flexible printhead is described. The printhead includes a number of printhead die, a printhead die including a number of nozzles to deposit an amount of fluid onto a print medium. The printhead also includes a fluid delivery system to deliver the amount of fluid from a fluid supply to the number of nozzles. The printhead also includes a number of electrical circuits to electronically couple the number of printhead die with a printing device. The printhead also includes a flexible substrate on which the number of printhead die and the number of electrical circuits are mounted. ## Claims ### Claim 1 A printhead comprising: multiple printhead dies, the printhead dies comprising a number of nozzles to deposit an amount of fluid onto a print medium; a fluid delivery system to deliver the amount of fluid from a fluid supply to the number of nozzles; a number of electrical circuits to electronically couple the multiple printhead dies with a printing device; and a flexible substrate on which the multiple printhead dies and the number of electrical circuits are mounted, wherein the flexible substrate is curved to follow a contour of a media transport assembly. ### Claim 2 (depends on 1) The printhead of claim 1, wherein the flexible substrate is at least one of a metallic material, a ceramic material, and a polymeric material. ### Claim 3 (depends on 1) The printhead of claim 1, wherein the flexible substrate has a radius of curvature to match a contour of a media transport assembly. ### Claim 4 (depends on 1) The printhead of claim 1, wherein the flexible substrate is less than a half a millimeter thick. ### Claim 5 (depends on 1) The printhead of claim 1, wherein the printhead is a page-wide printhead. ### Claim 6 (depends on 1) The printhead of claim 1, wherein the multiple printhead dies are sliver dies between 100 and 1,000 microns wide. ### Claim 7 (depends on 1) The printhead of claim 1, further comprising a film substrate in which the number of electrical circuits are formed as patterned metallic traces. ### Claim 8 (depends on 1) The printhead of claim 1, wherein a radius of curvature of the flexible substrate matches a web press or a drum printer. ### Claim 9 (depends on 1) The printhead of claim 1, wherein the media transport assembly is round. ### Claim 10 A method for forming a printhead comprising: forming a first layer of the printhead, the first layer comprising: a printhead die that includes a number of nozzles; and flexible electronic circuitry to provide electrical signals to the printhead die, the electrical signals to control ejection of fluid from the number of nozzles; forming a second layer of the printhead, the second layer comprising a flexible substrate on which the printhead die and the flexible electronic circuitry are to be mounted; and attaching the first layer of the printhead to the second layer of the printhead to form a flexible printhead. ### Claim 11 (depends on 10) The method of claim 10, wherein: forming the first layer of the printhead comprises positioning the flexible electronic circuitry and the printhead die on a release substrate; and forming the second layer of the printhead comprises positioning a circuit adhesive on a portion of a surface of the flexible substrate that will receive the flexible electronic circuitry. ### Claim 12 (depends on 10) The method of claim 10, further comprising forming a channel in the flexible substrate that aligns with the nozzles in the printhead die to facilitate fluid flow from a fluid supply to the number of nozzles. ### Claim 13 (depends on 12) The method of claim 12, wherein forming the channel in the flexible substrate comprises chemically etching the flexible substrate to form the channel. ### Claim 14 (depends on 12) The method of claim 12, wherein forming the channel in the flexible substrate comprises mechanically removing material from the flexible substrate to form the channel. ### Claim 15 (depends on 12) The method of claim 12, wherein the channel in the flexible substrate is formed after the first layer of the printhead is attached to the second layer of the printhead. ### Claim 16 (depends on 10) The method of claim 10, wherein attaching the first layer of the printhead to the second layer of the printhead comprises curing an adhesive between the first layer of the printhead and the second layer of the printhead. ### Claim 17 A printhead comprising: a number of nozzles in a printhead die, the number of nozzles to deposit an amount of fluid onto a print medium, each nozzle comprising; a firing chamber to hold the amount of fluid; an opening to dispense the amount of fluid onto the print medium; and an ejector to eject the amount of fluid through the opening; a number of flexible electrical circuits to electronically couple the printhead die with a printing device; and a flexible substrate on which the printhead die and the number of flexible electrical circuits are mounted, wherein the flexible substrate is curved to follow a contour of a media transport assembly. ### Claim 18 (depends on 17) The printhead of claim 17, wherein an angle of the openings in a printhead die are such that fluid drops ejected from the openings are closer or farther apart on the print media then the corresponding distance between the openings. ### Claim 19 (depends on 17) The printhead of claim 17, wherein the flexible substrate is a stainless steel foil less than 100 microns thick. ### Claim 20 (depends on 17) The printhead of claim 17, wherein the flexible substrate has a radius of curvature to match the contour of the media transport assembly.