To provide a method for manufacturing a high-quality seamless belt at a low cost by preventing oxidative degradation of a resin composition.
The method for manufacturing a seamless belt includes: a process of putting pellets of a resin composition into an annular flow channel having a melting body of a resin composition including a thermoplastic resin, and using a piston having a pressing surface whose temperature is adjusted less than the melting point of the resin composition, to press the pellets until the pressing surface is brought into contact with the melting body to thereby melt the pellets by pressing; a process of radially discharging the melting body from an annular die; a process of using a tight contact device to bring the discharged melting body into tight contact with a part of a cylindrical mold to cut off the communication of gas at the part in tight contact; a process of moving the cylindrical mold, the tight contact device, and the annular die relatively in the axial direction, and applying the melting body to an inner wall surface of the cylindrical mold to form a cylindrical layer; a process of filling gas in a space defined by the tight contact device, the cylindrical layer and the annular die, and bringing the cylindrical layer into tight contact with the inner wall surface of the annular mold; and a process of solidifying the cylindrical layer.
Ishibashi Masayuki
Masaaki Ogata