# US 12,474,656 B2 · Film, tubular fixing member, fixing device, and image forming apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,474,656 B2 - Document ID: US12474656B2 - Status: Granted - Kind: B2 - Application number: 18/624,642 - Filed: 2024-04-02 - Published: 2025-03-13 - Granted: 2025-11-18 - Earliest claimed: 2023-09-13 - Assignees: FUJIFILM Business Innovation Corp. - Applicants: Fujifilm Business Innovation Corp. - Inventors: Hiroaki Tanaka; Taiki Nagamatsu; Kenji Kajiwara; Tomotake Inagaki; Ryohei Yoshikawa - Web page: https://patentgrep.com/patent/US12474656B2 ## CPC - G03G 15/206: {Structural details or chemical composition of the pressure elements and layers thereof} - C08J 5/18: Manufacture of films or sheets - G03G 15/2057: {relating to the chemical composition of the heat element and layers thereof} - C08J 2379/08: Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors - C08K 7/06: Elements - C08K 7/18: inorganic - C08K 2201/001: Conductive additives - G03G 2215/2054: Inorganic filler, e.g. silica powder - G03G: ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY - C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29) - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) ## Abstract A film contains at least one macromolecular compound selected from the group consisting of resins and rubbers and an electrically conductive filler including at least a needle-shaped filler and dispersed in the macromolecular compound. The content of the electrically conductive filler is 40% by volume or more. ## Claims ### Claim 1 A film comprising: at least one macromolecular compound selected from the group consisting of resins and rubbers; and an electrically conductive filler including at least a needle-shaped filler and at least one of a spherical filler or a plate-shaped filler, the electrically conductive filler being dispersed in the macromolecular compound, wherein the content of the electrically conductive filler is 55% by volume or more and 70% by volume or less. ### Claim 2 (depends on 1) The film according to claim 1, wherein the film has a volume resistivity of 1,000 ohm·cm or less as measured at a measurement voltage of 0.1 V, and wherein the applied voltage dependence of the volume resistivity that is defined as the difference between the volume resistivity measured at a measurement voltage of 0.02 V and the volume resistivity measured at a measurement voltage of 0.1 V is 600 ohm·cm or less. ### Claim 3 (depends on 2) The film according to claim 2, wherein the applied voltage dependence of the volume resistivity that is defined as the difference between the volume resistivity measured at a measurement voltage of 0.02 V and the volume resistivity measured at a measurement voltage of 0.1 V is 300 ohm·cm or less. ### Claim 4 (depends on 3) A tubular fixing member comprising the film according to claim 3. ### Claim 5 (depends on 2) A tubular fixing member comprising the film according to claim 2. ### Claim 6 (depends on 1) The film according to claim 1, wherein the applied voltage dependence of a surface resistivity that is defined as the difference between the surface resistivity measured at a measurement voltage of 0.02 V and the surface resistivity measured at a measurement voltage of 0.1 V is 200 ohm/sq or more. ### Claim 7 (depends on 6) The film according to claim 6, wherein the applied voltage dependence of the surface resistivity that is defined as the difference between the surface resistivity measured at a measurement voltage of 0.02 V and the surface resistivity measured at a measurement voltage of 0.1 V is 400 ohm/sq or more. ### Claim 8 (depends on 7) A tubular fixing member comprising the film according to claim 7. ### Claim 9 (depends on 6) A tubular fixing member comprising the film according to claim 6. ### Claim 10 (depends on 1) The film according to claim 1, wherein the content of the electrically conductive filler is 60% by volume or more. ### Claim 11 (depends on 10) A tubular fixing member comprising the film according to claim 10. ### Claim 12 (depends on 1) The film according to claim 1, wherein the total amount of the spherical filler and the plate-shaped filler with respect to the total amount of the electrically conductive filler is 20% by volume or more and 60% by volume or less. ### Claim 13 (depends on 12) The film according to claim 12, wherein the total amount of the spherical filler and the plate-shaped filler with respect to the total amount of the electrically conductive filler is 30% by volume or more and 50% by volume or less. ### Claim 14 (depends on 1) The film according to claim 1, wherein the needle-shaped filler is a carbon material filler. ### Claim 15 (depends on 1) A tubular fixing member comprising the film according to claim 1. ### Claim 16 (depends on 15) A fixing device comprising: a first rotatable member; and a second rotatable member disposed in contact with an outer surface of the first rotatable member, wherein at least one of the first rotatable member and the second rotatable member is the tubular fixing member according to claim 15, and wherein a recording medium having an image formed on a surface thereof is caused to pass through a contact portion between the first rotatable member and the second rotatable member to fix the toner image. ### Claim 17 (depends on 16) An image forming apparatus comprising: an image holding member; a charging device that charges a surface of the image holding member; an electrostatic latent image forming device that forms an electrostatic latent image on the charged surface of the image holding member; a developing device that develops the electrostatic latent image formed on the surface of the image holding member with a developer containing a toner to thereby form a toner image; a transferring device that transfers the toner image onto a surface of a recording medium; and the fixing device according to claim 16 that fixes the toner image to the recording medium.