GOLF CLUB BY REVERSE INTERLAMINAR PLACEMENT (RIP) TECHNOLOGY

1 . A golf club shaft, comprising:

an elongated, generally tapered shaft having a generally circular transverse cross-sectional shape, the circular wall of the shaft including:

at least one flexural rigidity layer disposed around the entire length of the shaft, reinforcement fibers of the flexural rigidity layer substantially oriented in the longitudinal direction of the shaft, and

an outer layer, having no longitudinally-oriented fibers, disposed concentrically about an outermost flexural rigidity layer and extending at least one third the length of the shaft from a tip end of the shaft.

2 . The golf club shaft according to claim 1 , wherein the outer layer comprises at least one outer bias layer, each outer bias layer having unidirectional reinforcement fibers angled with respect to the shaft's longitudinal axis, the unidirectional reinforcement fibers of each successive outer bias layer oriented at a substantially equal but opposite angle with respect to the orientation of fibers belonging to any adjacent outer bias layer.

3 . The golf club shaft according to claim 1 or claim 2 , wherein the at least one outer layer extends the entire length of the shaft.

4 . The golf club shaft according to claim 2 , further comprising:

at least two inner bias layers alternatingly disposed beneath the entire length of the innermost flexural rigidity layer, each inner unidirectional bias layer having unidirectional fibers angled complementarily to the fibers of the next of the inner unidirectional bias layers with respect to the shaft axis and disposed substantially from the tip end to the butt end of the shaft.

5 . The golf club shaft according to claim 3 , further comprising:

at least two inner unidirectional bias layers alternatingly disposed, for the entire length of the shaft, beneath an inner surface of the innermost base unidirectional flex layer, each inner unidirectional bias layer having unidirectional fibers angled complementarily to the fibers of the next of the inner unidirectional bias layers with respect to the shaft axis and disposed substantially from the tip end to the butt end of the shaft.

6 . The golf club shaft according to claim 2 , wherein the unidirectional fibers of the outer unidirectional bias layers are oriented between about +35° and +55° or between about −35° and −55° with respect to the longitudinal axis of the shaft such that the fibers of one outer unidirectional bias layer are oriented at a substantially equal but opposite angle with respect to the orientation of fibers belonging to the next outer unidirectional bias layer.

7 . The golf club shaft according to claim 4 , wherein the unidirectional fibers of the inner unidirectional bias layers are oriented between about +35° and +55° or between about −35° and −55° with respect to the longitudinal axis of the shaft such that the fibers of one inner unidirectional bias layer are oriented at a substantially equal but opposite angle with respect to the orientation of fibers belonging to the next inner unidirectional bias layer.

8 . The golf club shaft according to claim 2 , wherein the outer unidirectional bias layers are formed by a tape having unidirectional reinforcement fibers and wound spirally along the selected longitudinal portion of the shaft.

9 . The golf club shaft according to claim 1 wherein the outer layer extends at least half the length of the shaft from a tip end of the shaft.

10 . A method of producing a golf club shaft, comprising:

providing an elongated mandrel having an outside surface shaped to form the inside surface of the shaft;

applying about the entire length of the mandrel at least one flexural rigidity layer of composite material, reinforcing fibers of which are oriented substantially parallel to the longitudinal axis of the mandrel; to form a tubular body for the shaft; and

applying concentrically about the at least one flexural rigidity layer, at least one outer layer having no longitudinally-oriented fibers, the at least one outer layer disposed over at least one third the longitudinal length of the shaft.

11 . The method according to claim 10 , further comprising:

applying about the entire length of the mandrel at least one bias layer of composite material, unidirectional reinforcing fibers of which are oriented at an angle with respect to the shaft's longitudinal axis, the unidirectional reinforcement fibers successive bias layers oriented at substantially equal but opposite angles with respect to the orientation of fibers belonging to an adjacent bias layer, wherein

the at least one flexural rigidity layer is applied to the mandrel first, forming an innermost one or more bias layers of the shaft, the at least one flexural rigidity layer and at least one outer layer respectively disposed about the mandrel.

12 . The method according to claim 10 , wherein the at least one outer layer includes unidirectional reinforcement fibers oriented at an angle with respect to the longitudinal direction of the shaft, each adjacent outer layer having its reinforcement fibers oriented at a substantially equal but opposite angle with respect to reinforcement fibers of an adjacent outer layer.

13 . The method according to claim 11 wherein the angle of the unidirectional reinforcing fibers of the at least one bias layer is between about +35° and +55° or between about −35° and −55° with respect to the longitudinal axis of the shaft.

14 . The method according to claim 10 wherein at least one of the outer layers is formed by spirally wrapping a tape comprising the unidirectional fibers.

15 . The method according to claim 11 wherein at least one of the bias layers is formed by spirally wrapping a tape comprising the unidirectional fibers of each bias layer.

16 . The method according to claim 10 wherein the at least one outer layer is disposed over at least half the longitudinal length of the shaft.