# US 12,179,394 B2 · Multilayer core molding method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,179,394 B2 - Document ID: US12179394B2 - Status: Granted - Kind: B2 - Application number: 18/164,614 - Filed: 2023-02-06 - Published: 2023-06-15 - Granted: 2024-12-31 - Earliest claimed: 2019-12-05 - Assignees: Bridgestone Sports Co., Ltd. - Applicants: Bridgestone Sports Co., Ltd. - Inventors: Kazunori Nakajima; Satoru Judai - Web page: https://patentgrep.com/patent/US12179394B2 ## CPC - B29C 43/18: incorporating preformed parts or layers, e.g. compression moulding around inserts or for coating articles {(B29C43/206 takes precedence)} - B29C 43/146: {for making multilayered articles} - B29C 43/203: {Making multilayered articles} - B29C 43/52: Heating or cooling - B29C 43/58: Measuring, controlling or regulating {(for bank adjustment in calendering B29C43/245)} - B29C 2043/182: {completely} - B29C 2043/366: {plates pressurized by an actuator, e.g. ram drive, screw, vulcanizing presses} - B29C 2043/5816: {temperature} - B29L 2031/546: {Golf balls} - 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) - B29L: INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES ## Abstract A multilayer core molding method includes: an upstream process of obtaining an intermediate molded body 33; and a downstream process of performing molding using a downstream process molding apparatus 2, and wherein the downstream process includes: an intermediate molded body arrangement step of arranging the intermediate molded body on the intermediate plate cavity surface or the first downstream process mold cavity surface; and a first vulcanization step, performed after the intermediate molded body arrangement step, of vulcanization-molding the intermediate molded body until it is substantially or completely vulcanized, in a state in which at least the first downstream process mold and the intermediate plate are closed against each other. ## Claims ### Claim 1 A multilayer core molding method for molding a multilayer core of a golf ball, the multilayer core molding method comprising: an upstream process of obtaining an intermediate molded body; and a downstream process of performing molding using a downstream process molding apparatus, wherein the intermediate molded body includes: an inner core; and an unvulcanized or semi-vulcanized first outer core material that covers only part of a surface of the inner core and is integrated with the inner core, and the downstream process molding apparatus includes: a first downstream process mold including a substantially hemispherical first downstream process mold cavity surface; a second downstream process mold including a substantially hemispherical second downstream process mold cavity surface; and an intermediate plate including a substantially hemispherical intermediate plate cavity surface configured to be arranged facing the first downstream process mold cavity surface, and wherein the downstream process includes: an intermediate molded body arrangement step of arranging the intermediate molded body on the intermediate plate cavity surface or the first downstream process mold cavity surface; and a first vulcanization step, performed after the intermediate molded body arrangement step, of vulcanization-molding the intermediate molded body until the intermediate molded body is substantially or completely vulcanized, in a state in which at least the first downstream process mold and the intermediate plate are closed against each other. ### Claim 2 (depends on 1) The multilayer core molding method according to claim 1, wherein the downstream process further includes: an intermediate plate removal step, performed after the first vulcanization step, of removing the intermediate plate in a state in which the intermediate molded body is held on the first downstream process mold cavity surface; a second outer core arrangement step, performed after the intermediate plate removal step, of arranging a second outer core material on the second downstream process mold cavity surface or the intermediate molded body; and a second vulcanization step, performed after the second outer core arrangement step, of integrally vulcanization-molding the intermediate molded body and the second outer core material, in a state in which the first downstream process mold and the second downstream process mold are closed against each other. ### Claim 3 (depends on 1) The multilayer core molding method according to claim 1, wherein, in the first vulcanization step, part of the first outer core material of the intermediate molded body sticks out from between the first downstream process mold cavity surface and the intermediate plate cavity surface to form a first flash. ### Claim 4 (depends on 1) The multilayer core molding method according to claim 1, wherein, in the first vulcanization step, a temperature T1 of the first downstream process mold and a temperature T3 of the intermediate plate satisfy the relation T1≥T3. ### Claim 5 (depends on 1) The multilayer core molding method according to claim 1, wherein, the first vulcanization step is performed in a state in which the first downstream process mold, the second downstream process mold, and the intermediate plate are closed against each other, and in the first vulcanization step, a temperature T1 of the first downstream process mold, a temperature T2 of the second downstream process mold, and a temperature T3 of the intermediate plate satisfy the relation T2≥T1≥T3. ### Claim 6 (depends on 1) The multilayer core molding method according to claim 1, wherein in the first vulcanization step, a temperature T1 of the first downstream process mold and a temperature T3 of the intermediate plate satisfy the relation T1=T3. ### Claim 7 (depends on 1) The multilayer core molding method according to claim 1, wherein the first vulcanization step is performed in a state in which the first downstream process mold, the second downstream process mold, and the intermediate plate are closed against each other, and in the first vulcanization step, a temperature T1 of the first downstream process mold, a temperature T2 of the second downstream process mold, and a temperature T3 of the intermediate plate satisfy the relation T1=T2=T3. ### Claim 8 (depends on 1) The multilayer core molding method according to claim 1, wherein in the first vulcanization step, a temperature T1 of the first downstream process mold satisfies 80° C.T3. ### Claim 10 (depends on 1) The multilayer core molding method according to claim 1, wherein, the first vulcanization step is performed in a state in which the first downstream process mold, the second downstream process mold, and the intermediate plate are closed against each other, and in the first vulcanization step, a temperature T1 of the first downstream process mold, a temperature T2 of the second downstream process mold, and a temperature T3 of the intermediate plate satisfy the relation T2>T1>T3. ### Claim 11 (depends on 1) The multilayer core molding method according to claim 1, wherein, in the upstream process, molding is performed using an upstream process molding apparatus, and the upstream process molding apparatus includes: a first upstream process mold including a first upstream process mold cavity surface; and a second upstream process mold including a second upstream process mold cavity surface, and the upstream process molding apparatus is configured to define an upstream process mold cavity between the first upstream process mold cavity surface and the second upstream process mold cavity surface, in a state in which the first upstream process mold and the second upstream process mold are closed against each other, and wherein the upstream process includes: an inner core arrangement step of arranging the vulcanized inner core on the second upstream process mold cavity surface; and a covering step, performed after the inner core arrangement step, of covering the inner core with the first outer core material to obtain the intermediate molded body. ### Claim 12 (depends on 11) The multilayer core molding method according to claim 11, wherein, the covering step uses extrusion molding to cover the inner core with the first outer core material. ### Claim 13 (depends on 11) The multilayer core molding method according to claim 11, wherein, in the covering step, the inner core is covered with the first outer core material inside the upstream process mold cavity, in a state in which the first upstream process mold and the second upstream process mold are closed against each other.