A prepreg includes composition elements [A], [B], and [C] described below,

[A] a reinforcing fiber,

[B] a thermosetting resin, and

[C] a thermoplastic resin.

[B] contains a thermoplastic resin having an aromatic ring with an amount of 10% or more by mass, a resin region containing [B] is present on one surface of the prepreg, a resin region containing [C] is present on another surface of the prepreg, and [A] that crosses over a boundary surface between the resin region containing [B] and the resin region containing [C] and that is in contact with both resin regions is present.

A composite rim for a bicycle wheel that has a wall of structural fibers incorporated in a thermosetting polymeric material and a plurality of spoke attachment seats. The composite material includes at least one layer of woven bi-directional fibers where some fibers are in a nominal direction substantially parallel to the circumferential direction of the rim and some fibers are substantially orthogonal to the circumferential direction of the rim.

A bicycle wheel has a wheel frame. The wheel frame is a hollow and annular frame and is composited by multiple equally sized wheel bars. Each one of the wheel bars has two halves connected to each other to form the wheel bar, and each one of the two halves being made by laminating, heating and forming a thermoplastic prepreg. The equally sized wheel bars are connected to each other to form the bicycle wheel.

Embodiments disclosed herein relate to composite laminate structures including a polymer layer having sp.sup.2 carbon-containing material and improved heat release properties, and methods of making the same.

A polyimide laminated film containing a thermoplastic polyimide layer that includes a block (A) having a storage elastic modulus of 0.15 GPa or more at 380 C. and a block (B) having a storage elastic modulus of 0.10 GPa or less at 380 C. is used as a polyimide laminated film that has high peel strength and can suppress occurrence of a crack in an alkaline environment.

A bicycle wheel has a wheel frame. The wheel frame is a hollow and annular frame and is composited by multiple equally sized wheel bars. Each one of the wheel bars has two halves connected to each other to form the wheel bar, and each one of the two halves being made by laminating, heating and forming a thermoplastic prepreg. The equally sized wheel bars are connected to each other to form the bicycle wheel.

A laminated structure has a first layer formed from a fiber reinforced plastic, a second layer formed from a fiber reinforced plastic and arranged opposed to the first layer, a first core layer formed from a first resin foam and arranged between the first layer and the second layer, and a second core layer formed from a second resin foam and arranged between the first core later and the second layer. The first resin foam has a higher flame resistance than the second resin foam. A laminated structure having flame resistance and high strength enough to endure a bird strike or the like at the same time can be manufactured at relatively low manufacturing cost.

A sandwich component has a first cover layer, a second cover layer, and a core disposed therebetween. In the sandwich component, the cover layers are each formed from an outer layer made of a fiber-reinforced thermoplast material having greater resistance to a certain solvent and, fused therewith, an inner layer made of a thermoplast material having lower resistance to the solvent. The core has outer layers, each of which is formed from a thermoplast material having lower resistance to the solvent, and an inner structure, which is formed entirely or partially from a thermoplast material having greater resistance to the solvent. The inner layers of the cover layers were each fused with one of the outer layers of the core with the use of the solvent.

A sandwich component and method of producing the sandwich component are provided wherein the sandwich component has a first cover layer, a second cover layer, and a core disposed therebetween. In the sandwich component, the cover layers are each formed from an outer layer made of a fiber-reinforced high-melting-point thermoplast material and, fused therewith, an inner layer made of a low-melting-point thermoplast material. The core has outer layers, each of which is formed from a low-melting-point thermoplast material, and an inner structure, which is formed entirely or partially from a high-melting-point thermoplast material. The inner layers of the cover layers were each fused with one of the outer layers of the core.

A composite rim for a bicycle wheel that has a wall of structural fibers incorporated in a thermosetting polymeric material and a plurality of spoke attachment seats. The composite material includes at least one layer of woven bi-directional fibers where some fibers are in a nominal direction substantially parallel to the circumferential direction of the rim and some fibers are substantially orthogonal to the circumferential direction of the rim.