Abstract: On a folding section of the thermoplastic sheet there is provided one or more thin-walled section, extending in a longitudinal direction of the folding section, whose minimum thickness is not less than 1/10 and not more than ? the thickness of the thermoplastic resin sheet. Thus, it is possible to provide a box in which rebound of the folding section is reduced and an operation efficiency upon setting up the box and putting goods into the box can be improved.

Abstract: On a folding section of the thermoplastic sheet there is provided one or more thin-walled section, extending in a longitudinal direction of the folding section, whose minimum thickness is not less than {fraction (1/10)} and not more than ⅔ the thickness of the thermoplastic resin sheet. Thus, it is possible to provide a box in which rebound of the folding section is reduced and an operation efficiency upon setting up the box and putting goods into the box can be improved.

Abstract: A mold assembly for making a multilayer molded article comprising: a first mold; a second mold; a shut-off pin slidably received in a resin-supplying gate opened to a cavity face of the first mold; a pin-driving unit for moving the shut-off pin among an opening position, a closing position and a projecting position; a resin-supplying unit for supplying a molten thermoplastic resin from said resin-supplying gate; and a press unit for moving the molds between an open position and a closed position.

Abstract: A method is disclosed for making a multi-layer up molded article.

Abstract: A drive shaft made of fiber-reinforced plastics comprising a pipe made of fiber-reinforced plastics to which a fitting is connected, in which a connecting portion of the pipe and a connecting portion of the fitting engage each other through bite of serrations formed on the inner or outer surface of the connecting portion of the fitting into the connecting portion of the pipe, with the space between the pipe and the fitting at the biting sites being filled with an adhesive.

Abstract: Inorganic fiber such as carbon fiber is modified by a surface treatment with a dinitrodiamine compound represented by the formula of ##STR1## wherein X is a divalent aliphatic, alicyclic or aromatic group which may contain halogen or oxygen in the group, R.sup.1 is hydrogen, an aliphatic group, an alicyclic group or an aromatic group, with the proviso that two nitrogen atoms linking through X may further link through R.sup.1 when both X and R.sup.1 are the aliphatic groups, and R.sup.2 and R.sup.3 independently of one another are each hydrogen or an alkyl of 1 to 12 carbon atoms, with the proviso that R.sup.2 and R.sup.3 may conjointly form a ring. The inorganic fiber thus modified is useful for reinforcement of resins.

Abstract: A drive shaft made of fiber reinforced plastic includes pipe made of fiber reinforced plastic to which a fitting is connected. A connecting portion of the fiber-reinforced resin-made pipe and a connecting portion of the fitting engage each other through the bite of serrations formed on the outer side or inner side of the fitting, with a film, e.g., a metallic foil, being interposed therebetween.

Abstract: A fiber-reinforced metal composite material comprising a metal or alloy as the matrix and an inorganic fiber as the reinforcing material, characterized in that at least one element selected from the group consisting of elements belonging to the fourth or higher periods of the group (IA) in the periodic table, elements belonging to the fifth or higher periods of the group (IIA) in the periodic table, and Bi and In in the form of simple substance or organic or inorganic compound is incorporated into either one or both of the matrix metal or the reinforcing material in an amount of 0.0005 to 10% by weight (calculated in terms of the element) so as to enhance the mechanical strength of the composite material.

Abstract: A fiber-reinforced metal composite material comprising a metal or alloy as the matrix and an inorganic fiber as the reinforcing material, characterized in that at least one element selected from the group consisting of tin, cadmium and antimony in the form of simple substance or organic or inorganic compound is incorporated into the matrix metal in an amount of 0.0005 to 10% by weight (calculated in terms of the element) so as to enhance the mechanical strength of the composite material.

Abstract: A fiber-reinforced metal composite material comprising a reinforcing material and a matrix, said reinforcing material being inorganic fibers containing at least two components selected from carbon (as a simple substance), metal oxides, metal carbides, metal nitrides and metal borides, and said matrix being metal alloys containing zinc and aluminum, or zinc and magnesium as main component.

Abstract: A fiber-reinforced metal composite material comprising a metal or alloy as the matrix and an inorganic fiber as the reinforcing material, characterized in that at least one element selected from the group consisting of elements belonging to the fourth or higher periods of the group (IA) in the periodic table, elements belonging to the fifth or higher periods of the group (IIA) in the periodic table, and Bi and In in the form of simple substance or organic or inorganic compound is incorporated into either one or both of the matrix metal or the reinforcing material in an amount of 0.0005 to 10% by weight (calculated in terms of the element) so as to enhance the mechanical strength of the composite material.

Abstract: A fiber-reinforced metal composite material comprising a metal or alloy as the matrix and an inorganic fiber as the reinforcing material, characterized in that at least one element selected from the group consisting of tin, cadmium and antimony in the form of simple substance or organic or inorganic compound is incorporated into the matrix metal in an amount of 0.0005 to 10% by weight (calculated in terms of the element) so as to enhance the mechanical strength of the composite material.

Abstract: A process for producing a fiber-reinforced metal composite material which comprises mixing an inorganic fiber with an aluminum alloy at a temperature of not lower than the melting point of said alloy to form a composite,(1) removing the composite from the mold at a temperature of not higher than the solid phase line of said alloy (i.e. a temperature at which a liquid phase appears in said alloy) and heating the composite to a temperature of more than the solid phase line and holding the temperature (heat treatment) during a definite time (Indirect method), or(2) without allowing to cool the composite to a temperature of not higher than the solid phase line (Direct method),quenching the composite to a temperature of 200.degree. C. or lower from a temperature of higher than the solid phase line but lower than the melting temperature.

Abstract: A process for preparing a fiber-reinforced metal composite material which comprises (1) combining an inorganic fiber comprising alumina as the main component and silica as the secondary component with an aluminum alloy containing at least one of copper, silicon, magnesium and zinc as the secondary component at a temperature of not lower than the melting point of said alloy to make a composite, (2) subjecting said composite to solid solution treatment, (3) quenching the treated composite and (4) optionally tempering the quenched composite at a temperature of from 100 to 250.degree. C.

Abstract: The present invention provides for a curable polyurethane composition comprising a keto compound and a liquid mixture of an organic aliphatic polyfunctional polyisocyanate and a compound having active hydrogen, the keto compound having the general formula: ##EQU1## wherein R.sub.1 and R.sub.2 are each an alkyl group, an aromatic group, and a heterocyclic group, which may be the same or different, and R.sub.2 is a lower alkylene or alkenyl group having 1 to 2 carbon atoms. The curable polyurethane composition is characterized by exhibiting a long pot life due to the existence of the aforementioned keto compound therein.