METHOD FOR MANUFACTURING FILM FOR DIAPHRAGM OF SPEAKER

• Main Authors: GONDA TAKASHI, ISHIDA JUNYA
• Format: Patent
• Language: English; Japanese
• Published: 24.06.2019
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; DEAF-AID SETS; ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKEACOUSTIC ELECTROMECHANICAL TRANSDUCERS; PERFORMING OPERATIONS; PUBLIC ADDRESS SYSTEMS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

To provide a method for manufacturing a film for a diaphragm of a speaker capable of securing heat resistance at 160°C or higher, and of improving durability of a diaphragm.SOLUTION: A method for manufacturing a film for a diaphragm of a speaker includes: melt-kneading a thermoplastic polyimide resin-containing molding material 1; continuously extrusion-molding a film 2 for a diaphragm of a speaker into a band shape from a T-die 13 using the molding material 1; and cooling the extrusion-molded film 2 while sandwiched between a pressure-bonding roll 17 and a cooling roll 18 to control a thickness of the cooled film 2 to 2 μm or more and 110 μm or less, control a tensile elastic modulus at 23°C of the film 2 after cooling to 1,000 N/mmor more and 3,000 N/mmor less, control a tensile elastic modulus at 160°C of the film 2 after cooling to 700 N/mmor more and 2,000 N/mmor less, control a specific gravity of the film 2 after cooling 2 to 1.2 or more and 1.4 or less, and control a loss tangent at 20°C of the film 2 after cooling to 0.010 or more.SELECTED DRAWING: Figure 1 【課題】１６０℃以上の耐熱性を確保でき、振動板の耐久性を向上させ得るスピーカの振動板用フィルムの製造方法を提供する。【解決手段】熱可塑性ポリイミド樹脂含有の成形材料１を溶融混練し、成形材料１を用いてＴダイス１３からスピーカの振動板用のフィルム２を連続的に帯形に押出成形し、押出成形したフィルム２を圧着ロール１７と冷却ロール１８の間に挟持させて冷却することにより、冷却したフィルム２の厚さを２μｍ以上１１０μｍ以下とし、冷却後のフィルム２の２３℃における引張弾性率を１０００Ｎ／ｍｍ２以上３０００Ｎ／ｍｍ２以下とするとともに、冷却後のフィルム２の１６０℃における引張弾性率を７００Ｎ／ｍｍ２以上２０００Ｎ／ｍｍ２以下とし、冷却後のフィルム２の比重を１．２以上１．４以下とし、冷却後のフィルム２の２０℃における損失正接を０．０１０以上とする。【選択図】図１