| 摘要 |
PURPOSE:To enhance radial crushing strength constant and durability and enable an ink to smoothly exude when printing, by forming a sintered nylon resin body from a powder of a eutectic mixture of a 6,6-nylon resin and a 6,10-nylon resin. CONSTITUTION:A magnet piece 9 is fitted into a hole 8' provided in a printing body fitting surface 8 of a platen substrate 7, and an ink-impregnated sintered nylon resin body 5 with an iron plate 6 fixed to the bottom surface thereof is replaceably fitted to the magnet piece 9. The sintered body 5 is produced as follows. First, 6,6-nylon resin pellets having a relative viscosity of 4.0 are mixed with 6,10-nylon resin pellets in a weight ratio of 7:3, the resultant mixed pellets are dissolved in a mixed solution based on ethylene glycol by heating to a temperature of 165-170 deg.C, followed by cooling to precipitate an eutectic mixture, thereby obtaining a powder of the eutectic mixture. Then, the powder is press- molded, followed by sintering to obtain a sintered body having a porosity of 15-35%, a Shore hardness of D67-79 and a radial crushing strength constant of 2.2-2.8kg/mm.<2>. Accordingly, printing quality and durability can be enhanced. |
