摘要:
The present invention provides blow bottles of a polyolefin resin having excellent transparency by the utilization of characteristics of the polypropylene. That is, they are the blow bottles of a polyolefin resin obtained by subjecting, to an extrusion blow molding method, a composition having a melt flow rate at 230.degree. C. of 0.5 to 10 g/10 minutes prepared by blending (A) 70 to 99.99% by weight of a propylene random copolymer of multi-component system having a crystalline melting point of 110.degree. to 145.degree. C. and containing 3 to 10% by weight of ethylene units with (B) a certain amount of two or three kinds of polyethylenes selected from 15 to 0.01% by weight of a straight-chain low-density polyethylene, 4 to 0.01% by weight of a low-density polyethylene and 4 to 0.01% by weight of a high-density polyethylene.
摘要:
A polypropylene composition for the production of various molded articles which are excellent in moldability, mold shrinkage factor on molding, rigidity, flexibility, impact resistance, in particular low-temperature impact resistance, transparency, gloss, stress-whitening resistance, and the balance thereof; various molded articles having the above properties; a propylene composition which is suitable for a base resin for the polypropylene composition; and a process for the production thereof. The propylene composition comprises a propylene homopolymer and a propylene-ethylene copolymer, the intrinsic viscosity of the copolymer ([&eegr;]RC) is in the range of 1.7 to 2.8 dl/g, the intrinsic viscosity ratio of the homopolymer to the copolymer ([&eegr;]RC/[&eegr;]pp) is in the range of 0.7 to 1.2 and a product [(WPP/WRC)×([&eegr;]RC/[&eegr;]pp)] of the weight ratio (WPP/WRC) of the homopolymer to the copolymer and the intrinsic viscosity ratio thereof is in the range of 1.0 to 3.0.
摘要:
A process for producing a hollow or sheet molded product having a superior appearance is provided, which process is characterized in that a multi-layer molded product having a surface layer (A) of a propylene random polymer of m.p. of 100.degree. to 150.degree. C. having a thickness of 1 to 20% of that of the molded product, and a substrate layer (B) of a thermoplastic resin of a m.p. higher than that of the propylene random polymer is formed and the surface layer (A) is heat-treated into a molten state, followed by immediately cooling to form a smooth surface.
摘要:
A process for producing a hollow or sheet molded product having a superior appearance is provided, which process is characterized in that a multi-layer molded product having a surface layer (A) of a propylene random polymer of m.p. of 100.degree. to 150.degree. C. having a thickness of 1 to 20% of that of the molded product, and a substrate layer (B) of a thermoplastic resin of a m.p. higher than that of the propylene random polymer is formed and the surface layer (A) is heat-treated into a molten state, followed by immediately cooling to form a smooth surface.
摘要:
By enlarging a range, in which an insertion and extraction port is opened, optical disks as stored are made easy to turn over to enable readily retrieve the optical disks as stored.A storage casing includes a bottom plate, a front plate provided on the bottom plate through a first hinge composed of a first bent portion along a first side of the bottom plate, a back plate provided on the bottom plate through a second hinge composed of a second bent portion along a second side opposed to the first side, and a pair of side plates provided on the back plate. When the front plate turns through the first hinge, it turns until engaging parts of turning pieces of the front plate engage with first turning restriction portions, and when the back plate turns through the second hinge, it turns until restriction portions of the side plates engage with second turning restriction portions. The front plate and the back plate are opened outward to enlarge an insertion and extraction port.
摘要:
By enlarging a range, in which an insertion and extraction port is opened, optical disks as stored are made easy to turn over to enable readily retrieve the optical disks as stored. A storage casing includes a bottom plate, a front plate provided on the bottom plate through a first hinge composed of a first bent portion along a first side of the bottom plate, a back plate provided on the bottom plate through a second hinge composed of a second bent portion along a second side opposed to the first side, and a pair of side plates provided on the back plate. When the front plate turns through the first hinge, it turns until engaging parts of turning pieces of the front plate engage with first turning restriction portions, and when the back plate turns through the second hinge, it turns until restriction portions of the side plates engage with second turning restriction portions. The front plate and the back plate are opened outward to enlarge an insertion and extraction port.
摘要:
A plastic molded product of olefin (co)polymer composition comprises 0.01-5.0 weight parts high molecular weight polyethylene with an intrinsic viscosity &eegr;E in the range of 15-100 dl/g measured in 135° C. tetralin and preferably 100 weight parts polypropylene. The high molecular weight polyethylene has an average particle size in the range of 1-5000 nm and is finely dispersed as fine granules in the polypropylene, so that high melt strength and high crystallization temperature are attained, enabling various molding methods to be performed with high speed productivity. Using the polymer composition, plastics such as a resin foam, a film, a sheet, a layered plastic article with a coated substrate surface, a hollow plastic article, an injection molded plastic article, a fiber, a nonwoven web or a continuous tube-shaped plastic are provided. The olefin (co)polymer composition is obtained by preparing high molecular weight polyethylene granules using e.g. a titanium transition metal compound catalyst, and adding these, e.g. as a polymerization catalyst of propylene, singly or together with a polyolefin preparing catalyst.
摘要:
In a DC brushless motor including a rotor assembly having permanent magnets and a stator assembly having coils arranged in the magnetic field generated by the permanent magnets of the rotor assembly, with the energization of the coils being controlled so as to impart a rotational torque to the rotor assembly; the permanent magnets of the rotor assembly are flat and are attached to a rotor yoke, which can be constructed as an octagonal prism, to provide a path for the magnetic flux emanating from the magnets and to support the flat magnets so that the latter form substantially a regular polygon in cross section. The magnets can be arranged with their poles in a north-south-north-south sequence against flat side walls of the rotor yoke to provide a flux density pattern that is substantially sinusoidal. Alternatively, the flat magnets can be arranged so that magnets of like polarization are disposed on either side of selected corners of a polygonal rotor yoke, thereby providing a flux density pattern that is substantially trapezoidal or rectangular.