A panel (1000) for a cabin of an aircraft, the panel (1000) including a laminate (150) with a first layer formed of lithiated carbon fibers (100), a second layer form of carbon fibers with a cathode lithium coating (200), and an electrolyte-containing separator (300) interposed between the first and the second layers and a pressure sensor (50a, 50b) on an outer surface of the laminate (150), and a switch (40) to regulate a voltage to the laminate (150) based on an output of the pressure sensor (50a, 50b) so that the panel (1000) expands.

A prepreg containing a carbon fiber [A] and a thermosetting resin [B], and in addition, satisfying at least one of the following (1) and (2). (1) a thermoplastic resin particle or fiber [C] and a conductive particle or fiber [D] are contained, and weight ratio expressed by [compounding amount of [C] (parts by weight)]/[compounding amount of [D] (parts by weight)] is 1 to 1000. (2) a conductive particle or fiber of which thermoplastic resin nucleus or core is coated with a conductive substance [E] is contained.

A panel (1000) for a cabin of an aircraft, the panel (1000) including a laminate (150) with a first layer formed of lithiated carbon fibers (100), a second layer form of carbon fibers with a cathode lithium coating (200), and an electrolyte-containing separator (300) interposed between the first and the second layers and a pressure sensor (50a, 50b) on an outer surface of the laminate (150), and a switch (40) to regulate a voltage to the laminate (150) based on an output of the pressure sensor (50a, 50b) so that the panel (1000) expands.

A fiber-reinforced composite material is provided which is capable of achieving CAI, ILSS, and interlaminar fracture toughness concurrently at high levels, in particular, capable of achieving high CAI. The composite material is composed of a laminated body including a plurality of reinforcing-fiber-containing layers and a resin layer in each interlaminar region between adjacent reinforcing-fiber-containing layers, wherein the resin layer is a layer wherein a cured product of a compound having in its molecule a benzoxazine ring of formula (1) and epoxy resin is impregnated with at least polyamide 12 powder: ##STR00001##
(R.sub.1: C1-C12 chain alkyl group or the like; H is bonded to at least one of the carbon atoms of the aromatic ring at ortho- or para-position with respect to C to which the oxygen atom is bonded).

A method produces a flat semi-finished product from a fiber composite material that contains individual carbon fibers, carbon fiber bundles, or a mixture thereof in a defined anisotropic fiber orientation and a thermoplastic matrix material. The anisotropy of the carbon fibers is created in a carding process using the high orientability of admixed non-carbon textile fibers, at least some of the non-carbon textile fibers being thermoplastic, and the carbon fibers having been isolated from waste or used parts. The flat fibrous web which is produced by a carding process and which has a specific orientation of the carbon fibers in the longitudinal direction is compressed into a sheet material under the effect of heat. This enables the use of carbon fibers, for example from production waste, as reinforcing fibers, whereby a less expensive raw material is provided and the carbon fibers are contained in the waste materials are recycled.

A prepreg containing a carbon fiber [A] and a thermosetting resin [B], and in addition, satisfying at least one of the following (1) and (2). (1) a thermoplastic resin particle or fiber [C] and a conductive particle or fiber [D] are contained, and weight ratio expressed by [compounding amount of [C] (parts by weight)]/[compounding amount of [D] (parts by weight)] is 1 to 1000. (2) a conductive particle or fiber of which thermoplastic resin nucleus or core is coated with a conductive substance [E] is contained.