摘要:
To provide a method for manufacturing an injection-molded article that can control an amount of flash generated during molding, and obtain a molded article of a high degree of crystallinity.In injection molding of a polyarylene sulfide resin composition, injection molding is performed using a mold having a heat-insulating layer formed on an inner surface of a mold, and at a mold temperature of 100° C. or less.It is preferable for the thermal layer to have a thermal conductivity ratio of 5 W/(m·K) or less.Furthermore, a composition including a polyimide resin can be exemplified as a preferable heat-insulating layer.The heat-insulating layer is preferably the one including a polyimide resin.
摘要:
Provided is a method for manufacturing a mold for manufacturing a molded article, by which not only is the occurrence of flash suppressed but also the crystallization of the surface is sufficiently accelerated when the mold temperature during the molding of a crystalline thermoplastic resin is set at Tc2−100° C. or less. Based on a relationship between crystallization rate and resin temperature of the crystalline thermoplastic resin, a temperature at which the crystalline thermoplastic resin filled into a mold has a sufficiently fast crystallization rate near a cavity surface and a retention time during which the crystalline thermoplastic resin in the mold is retained at a temperature equal to at least at a temperature at which the resin has the sufficiently fast crystallization rate are derived, such that the derived temperature and the derived retention time allow the molded article to have a surface whose crystallinity falls within a desired range, and a heat-insulating layer which, when mold temperature is Tc2−100° C. or less, allows a time, during which temperature near surface of the mold cavity is retained at no less than the derived temperature, to fulfill the derived retention time is provided.
摘要:
Provided is a method for manufacturing an injection-molded article, where the method is capable of obtaining a molded article having a high crystallinity while reducing the amount of flash generated and has excellent productivity. A polyarylene sulfide-based resin composition is injection-molded at a mold temperature of 100° C. or less using a mold on the inner surface of which a heat-insulating layer constituted of porous zirconia is formed. It is preferable that the heat-insulating layer is formed by a spraying method. Preferably, the heat-insulating layer has a thermal conductivity of 2 W/(m·K) or less. Preferably, the heat-insulating layer has a thickness of no less than 200 μm.
摘要:
The present invention is to provide a liquid crystal polymer molded article which has an excellent low warpage and is able to be suitably used particularly as a connector or the like. That is, a molded article of a liquid crystal composition in which 100 parts by weight of a liquid crystal polymer (A) and 5-100 parts by weight of a non-fibrous filler (B) are compounded where the non-fibrous filler is so dispersed that, when a diffraction peak of the non-fibrous filler is measured by a transmission method and a reflection method by means of a wide-angle X-ray diffraction, the diffraction peak of the non-fibrous filler which can be confirmed by the reflection method is not confirmed by the transmission method.
摘要:
Conductive circuits are formed by first metallizing a surface of a molded synthetic resin substrate to form an electrically conductive metallic film coating thereon of a thickness (e.g., between 0.2 to 2 .mu.m) effective to exhibit sufficient electrical conductivity for subsequent electroplating thereon. Non-circuit portions of the metallic film coating are thereafter removed with laser light so as to expose an underlying surface portion of the substrate and thereby form a circuit pattern on the substrate surface which is established by a portion of the metallic film remaining on the substrate surface. An additional metal layer may then be electroplated directly onto the remaining portion of the metallic film to thereby form the conductive circuit.
摘要:
Provided is a technology that sufficiently suppresses dimensional change in the usage environment even without applying heat treatment in advance to a resin-molded article constituted of a crystalline thermoplastic resin. A resin composition constituted of a crystalline thermoplastic resin is injection-molded using a mold on the inner surface of which a heat-insulating layer is formed. It is preferable, in the present invention, to use a mold on which a heat-insulating layer is formed, the layer being constituted of porous zirconia formed by spraying method and having a thermal conductivity of 2 W/(m·K) or less and a thickness of no less than 200 μm. The injection-molded article obtained by the manufacturing method of the present invention has a dimensional change rate of 0.2% or less when left for 2 hours in an environment of a mold temperature+20° C. where the mold temperature is that at the time of injection molding and is Tg+30° C. or more and Tg+80° C. or less, in which Tg is a glass transition temperature of the crystalline thermoplastic resin.
摘要:
To provide a resin material excellent in electric conductivity and judiciously usable in the manufacture of fuel cell separators and so forth. An electroconductive resin composition which comprises 100 parts by weight of a liquid-crystalline polymer (A) and 200 to 500 parts by weight of at least one species of graphite (B) selected from synthetic graphite, flake graphite and amorphous graphite with a fixed carbon content of not less than 95% by weight and an average particle size of 50 to 200 μm as incorporated in the polymer, the composition resulting from melt-kneading under such conditions that the ratio Q/N, where Q (kg) is the hourly extrusion throughput rate during kneading and N (rpm) is the screw revolution rate, may amount to 0.1 to 1.5, the composition having a volume resistivity of not more than 2×10−2 Ω·cm.
摘要:
To provide a resin material excellent in electric conductivity and judiciously usable in the manufacture of fuel cell separators and so forth. An electroconductive resin composition which comprises 100 parts by weight of a liquid-crystalline polymer (A) and 200 to 500 parts by weight of at least one species of graphite (B) selected from synthetic graphite, flake graphite and amorphous graphite with a fixed carbon content of not less than 95% by weight and an average particle size of 50 to 200 μm as incorporated in the polymer, the composition resulting from melt-kneading under such conditions that the ratio Q/N, where Q (kg) is the hourly extrusion through put rate during kneading and N (rpm) is the screw revolution rate, may amount to 0.1 to 1.5, the composition having a volume resistivity of not more than 2×10−2 Ω·cm.
摘要:
Provided is a technology for solving the drawback such as chipping of a heat-insulating layer which is caused by the contact of a heat-insulating layer formed on a first mold with a second mold at the mold parting surface. A mold divided into two or more is provided in which a heat-insulating layer is formed on a substantially entire surface of an inner wall surface of the mold, and the heat-insulating layer does not exist on a mold parting surface. For example, the mold is provided with a first mold occupying a majority of a cavity and a second mold which forms at least a part of the cavity together with the first mold, in which the first mold is provided with a flange part, and a part of a surface of the flange part constitutes a part of the mold parting surface.
摘要:
Provided is a technology for suppressing, in a mold having a heat-insulating layer formed therein, a problem of chipping of the heat-insulating layer and the like even when a penetrating member is inserted through a through-hole provided in the mold. The mold is provided with a mold body having a convex part on an inner wall surface of the mold body, a heat-insulating layer arranged on the inner wall surface, and a through-hole which penetrates the convex part in a thickness direction of the mold body and through which the penetrating member can be inserted. An outer periphery of the through-hole is inside an outer periphery of a top surface of the convex part. A spacing between the outer periphery of the through-hole on the top surface of the convex part and the outer periphery of the top surface of the convex part is preferably 0.5 mm or less.