# US 10,307,952 B2 · Cylindrical extruding die and method for producing seamless tube > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,307,952 B2 - Document ID: US10307952B2 - Status: Granted - Kind: B2 - Application number: 15/254,809 - Filed: 2016-09-01 - Published: 2017-03-09 - Granted: 2019-06-04 - Earliest claimed: 2015-09-07 - Assignees: Canon Kabushiki Kaisha - Applicants: Canon Kabushiki Kaisha - Inventors: Takayuki Hori; Masaaki Takahashi; Masayuki Morohashi; Akira Yane - Web page: https://patentgrep.com/patent/US10307952B2 ## CPC - B29B 7/582: {for discharging, e.g. doors} - B29B 7/325: {Static mixers (in general B01F25/42)} - B29B 7/82: Heating or cooling - B29C 48/022: {characterised by the choice of material} - B29C 48/09: Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels - B29C 48/29: in liquid form - B29C 48/32: with annular openings, e.g. for forming tubular articles - B29C 48/362: {using static mixing devices} - B29C 48/705: {in the die zone, e.g. to create flow homogeneity} - B29K 2101/12: Thermoplastic materials - B29K 2105/16: Fillers - B29K 2507/04: Carbon - B29L 2023/00: Tubular articles (B29L2024/00 takes precedence {; catheters B29L2031/7542}) - B29L 2029/00: Belts or bands {(conveyor belts B29L2031/7092; drive belts B29L2031/7094; fourdrinier belts B29L2031/733)} - B29B: PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS - B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00) - B29K: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR {MOULDS, } REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS - B29L: INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES ## Abstract A method for producing an electrically conductive seamless tube includes (1) preparing an electrically conductive resin composition containing a thermoplastic resin and an electrically conductive filler, (2) preparing a cylindrical extruding die including a cylindrical slit, at least one circumferential distribution channel communicating with the slit and distributing the resin composition that is plasticized in a circumferential direction of the slit, and at least one lead-in path that leads the plasticized resin composition into the circumferential distribution channel, the lead-in path containing a line mixer; (3) introducing the plasticized resin composition into the lead-in path toward the circumferential distribution channel; (4) introducing the plasticized resin composition flowing through the lead-in path into the circumferential distribution channel toward the slit; and (5) introducing the resin composition flowing through the circumferential distribution channel into the slit and extruding the resin composition from an outlet of the slit into a cylindrical shape. ## Claims ### Claim 1 A method for producing an electrically conductive seamless tube containing a thermoplastic resin serving as a binder and an electrically conductive filler dispersed in the thermoplastic resin, the method comprising the steps of: (1) preparing an electrically conductive resin composition containing a thermoplastic resin and an electrically conductive filler; (2) preparing a cylindrical extruding die comprising a cylindrical slit, a plurality of circumferential distribution channels communicating with the slit and configured to distribute the resin composition that is plasticized in a helical direction toward the slit, and a plurality of lead-in paths configured to lead the plasticized resin composition into the plurality of circumferential distribution channels, each of the plurality of lead-in paths containing a line mixer; (3) introducing the plasticized resin composition into the plurality of lead-in paths of the cylindrical extruding die toward the plurality of circumferential distribution channels; (4) introducing the plasticized resin composition that has flowed through the plurality of lead-in paths into the plurality of circumferential distribution channels toward the slit; and (5) introducing the plasticized resin composition that has flowed through the plurality of circumferential distribution channels into the slit and extruding the plasticized resin composition from an outlet of the slit into a cylindrical shape, wherein the step (3) comprises a step of interchanging the plasticized resin composition flowing through the plurality of lead-in paths between a flow near a wall of the plurality of lead-in paths and a flow in a radial center of the plurality of lead-in paths by the line mixers disposed in the plurality of lead-in paths, the plurality of lead-in paths has a circular cross section. ### Claim 2 (depends on 1) The method for producing a seamless tube according to claim 1, wherein the conductive filler comprises carbon black. ### Claim 3 (depends on 1) The method for producing a seamless tube according to claim 1, wherein the line mixer comprises a static mixer. ### Claim 4 (depends on 3) The method for producing a seamless tube according to claim 3, wherein the static mixer comprises at least one and at most 9 elements comprising a right element and a left element. ### Claim 5 (depends on 4) The method for producing a seamless tube according to claim 4, wherein the right element and the left element are alternately disposed.