PURPOSE: To obtain the title uniform frame having a dense structure free from voids, by packing a hollow laminate, impregnated with a thermosetting resin whose hollow part is provided with a pressing tube, into a mold under specific temperature conditions, followed by heating and curing the laminate.
CONSTITUTION: For example, high-moldulus fibers, e.g. carbon fibers, etc. and low-moldulus fibers, e.g. glass fibers, etc. are knitted and braided into cylinders separately, then laminated and impregnated with a thermosetting resin, e.g. epoxy resin, etc. The resin is semi-dried or semi-cured to form the hollow laminate 4. The pressing tube 8 is attached to the hollow part of the laminate 4. The laminate 4 is then packed into the groove 3 of the molds 1 and 2 under the following conditions: TrsTm (Tm is a mold temperature) when Trs is ≥140°C, Trs>Tm when Trs is <140°C. The laminate 4 is hot-cured while being pressurized by a fluid sent to the tube 8 to give the desired racket frame.
SHIMADA TOSHIO
SHIOKAWA SHIYOUGO
