To provide a tubular body of FRP(fiber reinforced plastic) which has excellent flexural strength and compression strength under the conditions of high temperature and moisture absorption and is suitable for a golf club shaft, a truss structure member, etc.
In a tubular body of FRP, FRP has reinforcing fibers which are oriented at an angle of ±25° to the axial direction of the tubular body, and the reinforcing fibers contain non-circular cross section fibers in which a minimum secondary profile degree Pmin defined by an expression of Pmin= Imin/A2 is 0.085 or more, where Imin is the minimum value of cross section secondary moment concerning an axis passing through the center of gravity of a single fiber; A is the cross section of the single fiber.
YOSHIOKA KENICHI
HIROSE TAKEHIKO
