Abstract: A prepreg having high processability and laminating performance and a method to produce such a prepreg is described, the prepreg comprising at least the components [A] to [E] shown below, and having a structure incorporating a first layer composed mainly of the component [A] and a first epoxy resin composition that contains the components [B] to [D] but which is substantially free of the component [E], and a second layer composed mainly of a second epoxy resin composition that contains the components [B] to [E], [A] carbon fiber, [B] epoxy resin, [C] curing agent, [D] thermoplastic resin, and [E] particles containing a thermoplastic resin as primary component and having a volume-average particle diameter of 5 to 50 ?m.

Abstract: A prepreg having high processability and laminating performance and a method to produce such a prepreg in an industrially advantageous way is described, the prepreg comprising at least the components [A] to [E] shown below, and having a structure incorporating a first layer composed mainly of the component [A] and a first epoxy resin composition that contains the components [B] to [D] but which is substantially free of the component [E], and a second layer composed mainly of a second epoxy resin composition that contains the components [B] to [E] and which is disposed adjacent to each surface of the first layer, the second epoxy resin composition being characterized in that its component [D] has a weight-average molecular weight of 2,000 to 30,000 g/mol and accounts for 5 to 15 parts by mass relative to the total quantity of its components [B] to [E], which accounts for 100 parts by mass, [A] carbon fiber, [B] epoxy resin, [C] curing agent, [D] thermoplastic resin, and [E] particles containing a thermoplasti

Abstract: A prepreg having a high processability and laminating performance in an automated lay-up device and serving to produce a cured product having good physical properties is described, and also a method for the production thereof, the prepreg comprising at least the components [A] to [E] listed blow and having a structure incorporating a first layer composed mainly of the component [A] and a first epoxy resin composition that contains the components [B] to [D] but is substantially free of the component [E] and a second layer composed mainly of a second epoxy resin composition that contains the components [B] to [E] and disposed adjacent to each surface of the first layer: [A] carbon fiber, [B] epoxy resin, [C] curing agent, [D] thermoplastic resin, and [E] particles containing a thermoplastic resin as primary component and having a volume-average particle diameter of 5 to 50 ?m.

Abstract: To measure a thickness or a coverage of a resin present at a surface layer of a prepreg in a non-contact manner using a simple technique, a measurement method for a resin state which is a method for measuring a state of a resin present at a surface layer of a prepreg impregnated with the resin in an unidirectional reinforced fiber base material includes: irradiating the surface layer of the prepreg with light from an irradiation source; receiving reflected light from the surface layer of the prepreg by a sensor; and calculating at least one of a thickness or a coated state of the resin present at the surface layer of the prepreg from intensity of the reflected light.

Abstract: A method of producing a fiber-reinforced resin by press-molding a prepreg preform contains a reinforcing fiber and a thermosetting resin, the method including (a) a preform production step of producing a preform; (b) a placement and preheating step of placing the preform in a mold and preheating the preform; (c) a pressing step of changing the preform into a product shape; and (d) a curing step of curing the preform while pressurizing the preform, wherein, at start of the pressing step (c), a degree of cure ?e of the thermosetting resin in a specific part of the preform is higher than a degree of cure ?i of the thermosetting resin in a region other than the specific part of the preform.

Abstract: A reinforcing fiber prepreg has a thermosetting resin as a matrix, wherein a part of the reinforcing fiber prepreg is a low-adhesion region that has been treated to reduce adhesiveness, and the resin reaction rate of the low-adhesion region is preferably 0.1%-20%; a tape and a wound body is obtained from the reinforcing fiber prepreg; and methods produce the reinforcing fiber prepreg and reinforcing fiber prepreg tape. This makes it possible to provide a reinforcing fiber prepreg tape of which the adhesiveness is appropriately reduced to enable suitable application to conveyance for AFP while using a simple technology.

Abstract: A production method for a fiber-reinforced plastic, in which a preform made of a reinforcing fiber substrate and having a three-dimensional shape and an inner mold operatable in a lateral direction different from an up-down direction are disposed in a mold cavity formed by an upper mold and a lower mold, and a state in which a plate thickness of the preform has been made greater than the thickness of a molded article to be obtained is brought about, and a matrix resin is injected and impregnated into the preform, and, after that, at least one of the upper mold and the lower mold is operated toward the other and the inner mold is operated in the lateral direction to pressurize the preform, whereby the thickness of the preform is controlled so as to be equal to a predetermined product's thickness, and subsequently the matrix resin is hardened by heating to obtain the molded article, and a production apparatus for a fiber-reinforced plastic for use in the production method.

Abstract: A simple technique measures a width of a gap present in a surface layer of a reinforced fiber laminate and is applicable to a fiber placement process. In the method in which at least one of a fiber reinforced substrate of the surface layer and a fiber reinforced substrate having an exposed part due to the presence of a gap is a unidirectional reinforced fiber substrate, the reinforced fiber laminate is irradiated with light in a direction vertical to an orientation direction of a continuous fiber present in a unidirectional reinforced fiber substrate of the reinforced substrate and at an acute angle with respect to a surface of the fiber reinforced substrate of the surface layer, and a sensor receives reflected light from the irradiation light, thereby calculating the width of the gap.

Abstract: A joint structure is a joint structure between a first member having a pillared end part made of a fiber-reinforced plastic and a second member different from the first member. The end part of the first member is reversely tapered in an axial direction, while a joining member is disposed along a reversely tapered form of the end part. The second member is provided in contact with an end face of the first member and connected to the joining member. A plurality of fibers substantially extending in the axial direction of the end part of the first member are provided within the end part and disposed to form a larger angle with the axial direction of the end part of the first member as they are disposed to be closer to a surface constituting the reversely tapered form in a radial direction of the end part.

Abstract: A joint structure is a joint structure between a first member having a pillared end part made of a fiber-reinforced plastic and a second member different from the first member. The end part of the first member is reversely tapered in an axial direction, while a joining member is disposed along a reversely tapered form of the end part. The second member is provided in contact with an end face of the first member and connected to the joining member. A plurality of fibers substantially extending in the axial direction of the end part of the first member are provided within the end part and disposed to form a larger angle with the axial direction of the end part of the first member as they are disposed to be closer to a surface constituting the reversely tapered form in a radial direction of the end part.

Abstract: A production method for a fiber-reinforced plastic, in which a preform made of a reinforcing fiber substrate and having a three-dimensional shape and an inner mold operatable in a lateral direction different from an up-down direction are disposed in a mold cavity formed by an upper mold and a lower mold, and a state in which a plate thickness of the preform has been made greater than the thickness of a molded article to be obtained is brought about, and a matrix resin is injected and impregnated into the preform, and, after that, at least one of the upper mold and the lower mold is operated toward the other and the inner mold is operated in the lateral direction to pressurize the preform, whereby the thickness of the preform is controlled so as to be equal to a predetermined product's thickness, and subsequently the matrix resin is hardened by heating to obtain the molded article, and a production apparatus for a fiber-reinforced plastic for use in the production method.

Abstract: The pressure vessel includes a tubular portion and a cover portion made of fiber reinforced plastics. The outer peripheral surface of an end portion of the tubular portion has a reverse-tapered shape of which the diameter is increased toward an end face. The cover portion includes a wedge-shaped member installed along the reverse-tapered shape of the outer periphery surface of the end portion of the tubular portion, an outer ring for covering the wedge-shaped member from the outside, an inner ring installed to cover an opening of the tubular portion and the wedge-shaped member and connected to the outer ring, and a sample cap connected to the inner ring.

Abstract: Providing an exhaust gas energy recovery device by which the optimal engine operating condition can be continuously maintained in a manner that the flow rate of the engine exhaust gas fed to the power turbine is regulated so that the scavenging air pressure becomes optimal in order that the engine performance (the fuel consumption rate) corresponding to the engine load and the engine speed becomes optima. The engine exhaust gas energy recovery device provided the engine load detecting sensor, the engine speed detecting sensor and the scavenging air pressure detecting sensor, the device regulating the flow rate of the exhaust gas streaming into the exhaust gas turbocharger via controlling the flow rate of the exhaust gas streaming into the power turbine of the exhaust gas energy recovery device, so that the scavenging air pressure is maintained at an arbitrarily ordered level and the engine is operated under a condition that the fuel consumption rate is minimal.