Jsp Corporation

Sumitomo Electric Industries, Limited

Mitsuru Shinohara

Masaharu Oikawa

Hisao Tokoro

Satoru Shioya

Akinobu Hira

Takuya Chiba

Hidehiro Sasaki

Tomoo Tokiwa

Tokunobu Nohara

Hiroshi Yamazaki

Keiichi Hashimoto

Masakazu Sakaguchi

Koichi Kimura

Masatoshi Kuroda

Masaomi Shima

Yoshiyuki Ishibashi

Kazutoshi Sasaki

Polylactic acid-based resin expanded beads obtained by releasing a softened, pressurized foamable resin composition, which has a polylactic acid-based resin and a physical blowing agent, to a low pressure atmosphere to foam and expand the resin composition, where the polylactic acid-based resin satisfies the conditions (1) to (3) shown below, and exhibits excellent secondary expansion properties and fusion bonding properties. A polylactic acid-based resin expanded beads molded article obtained by in-mold molding of the polylactic acid-based resin expanded beads exhibits excellent mechanical properties.MT&#x2264;30 mN&#x2003;&#x2003;(1)log MT&#x2264;0.93 log &#x3b7;&#x2212;1.75&#x2003;&#x2003;(2)CT&#x2265;600 sec&#x2003;&#x2003;(3)where MT represents a melt tension [mN] at 190&#xb0; C., &#x3b7; represents a melt viscosity [Pa&#xb7;s] at 190&#xb0; C. and a shear speed of 20 sec, and CTrepresents a half crystallization time [sec] at 110&#xb0; C.

Polylactic acid-based resin expanded beads and molded article thereof

A polylactic acid-based resin foamed molded article having a voidage of 5 to 45% by volume, a bulk density BD [g/cm] of 0.01 to 0.2 g/cmand a ratio FT/BD of a flexural strength FT [MPa] thereof to the bulk density BD in the range of 6 to 25 MPa&#xb7;cm/g.

Molded article of polylactic acid-based resin expanded beads

An electrostatic dissipating molded article having a surface resistivity of 1&#xd7;10to 1&#xd7;10&#x3a9; and obtained by in-mold molding of multi-layered polyolefin-based resin expanded beads each having an polyolefin-based resin expanded core layer and a polyolefin-based resin cover layer which covers the polyolefin-based resin expanded core layer and which is formed from a polyolefin-based resin (A), a polymeric antistatic agent (B) of a block copolymer of a polyether block and a polyolefin block, and an electrically conductive carbon black (C), the components (A) to (C) being present in a specific proportion.

Molded article of polyolefin-based resin expanded beads

An electrostatic dissipative, polypropylene-based resin expanded bead having an expanded core layer of a polypropylene-based resin, and a cover layer that covers the expanded core layer and that is composed of a mixed resin containing electrically conductive carbon black, wherein the mixed resin includes a polypropylene resin which forms a continuous phase and a polyethylene resin which forms dispersed phases dispersed in the continuous phase, with the electrically conductive carbon black being unevenly distributed to the dispersed phases side. In-mold molding of the expanded beads gave a molded article.

Polypropylene-based resin expanded beads, and polypropylene-based resin expanded beads molded article

An expanded bead of a polylactic acid resin, having an exterior surface, a surface region including the entire exterior surface and having a weight of one-sixth to one-fourth the weight of the expanded bead, and a center region located inside the surface region and having a weight of one-fifth to one-third the weight of the expanded bead, wherein the expanded bead, the surface region and the center region, after having been subjected to a pretreatment including a heat treatment at 110&#xb0; C. for 120 minutes followed by cooling at a cooling speed of 2&#xb0; C./min, have endothermic calorific values of (Br:endo), (Brs:endo) and (Brc:endo), respectively, when measured by heat flux differential scanning calorimetry at a heating speed of 2&#xb0; C./min in accordance with JIS K7122 (1987), and wherein (Br:endo) is greater than 25 J/g and (Brs:endo) is smaller than (Brc:endo) and is not smaller than 0 J/g.

Polylactic resin expanded beads and molded article of the expanded beads

A process produces a polyolefin-based resin expanded beads molded article that is excellent in bending deflection characteristics, high in porosity, low in bulk density and light in weight, and has interconnected void spaces. The process comprises filling, in a mold cavity, multi-layered polyolefin-based resin expanded beads each of which has a cylindrical, polyolefin-based resin expanded core layer and a polyolefin-based resin outer layer covering the expanded core layer and which satisfy specific requirements, introducing steam in the mold cavity to heat the multi-layered expanded beads filled in the mold cavity to fuse bond and mold the multi-layered expanded beads in the mold cavity.

Process for producing molded article of expanded polyolefin-based resin beads, and molded article of expanded polyolefin-based resin beads

Polylactic acid resin expanded beads exhibiting excellent fusion bonding at the time of in-mold molding have such a crystal structure that gives a first time DSC curve when heated according to heat flux differential scanning calorimetry referenced in JIS K7122(1987) and a second time DSC curve when thereafter cooled and then again heated, the second time DSC curve having a fusion peak having a reference peak temperature and the first time DSC curve having at least one fusion peak with a peak temperature higher than the reference peak temperature and another at least one fusion peak with a peak temperature not lower temperature than the reference peak temperature.

Polylactic acid resin expanded beads and molded article of polylactic acid resin expanded beads

A seed beads dispersing disperse system is obtained by dispersing olefin resin seed beadswith a specific tubular shape in an aqueous medium. Then, the olefin resin seed beadsare impregnated with styrene monomers and the styrene monomers are polymerized in the presence of a polymerization initiator by heating at a temperature in a specified range, to thereby obtain tubular thermoplastic resin composite beads. Expandable thermoplastic resin composite beads obtained by impregnating the thermoplastic resin composite beads with a blowing agent, expanded thermoplastic resin composite beads obtained by foaming and expanding the expandable thermoplastic resin composite beads, and a foamed molded article formed from the expanded thermoplastic resin composite beads by molding are also obtained.

Thermoplastic resin composite bead production method, expandable thermoplastic resin composite bead, expanded thermoplastic resin composite bead, and foamed molded article formed from expanded thermoplastic resin composite beads

Foamed polyolefin resin beads having antistatic properties obtained by a process, which includes dispersing polyolefin resin beads into an aqueous medium, injecting a blowing agent, stirring and allowing the polyolefin resin beads to foam and expand. The polyolefin resin beads are composite resin beads comprising a core layer of a core layer polyolefin resin and a covering layer of a covering layer polyolefin resin.

Method for producing foamed polyolefin resin beads

A hemispherical Luneberg dielectric lens including a hemispherical center layer having a hemispherical outer surface, and a plurality of hemispherical dome-shaped layers each having concentric hemispherical inner and outer surfaces, the outer surfaces of the center layer and dome-shaped layers having different diameters and the inner surfaces of said dome-shaped layers having different diameters. The center layer and dome-shaped layers are successively concentrically fitted into one another and integrated into a hemispherical shape. The center layer is a foam molding of ceramic-containing thermoplastic resin expanded beads, while each of said dome-shaped layers is a foam molding of thermoplastic resin expanded beads containing 0 to 80% by weight of a ceramic. The ceramic content per unit volume of the center and dome-shaped layers decreases from the center layer to the outermost dome-shaped layer, and the standard deviation of the apparent density of each of the center and dome-shaped layers is 0.07 g/cm3 or lower.

Luneberg dielectric lens and method of producing same

A process of producing a foamed molding, wherein expanded, substantially non-crosslinked polypropylene-based resin beads are heated in a mold to fuse-bond the beads together into a unitary body. Each of the expanded beads has been surface-modified with an organic peroxide.

Process of producing foamed molding from expanded polypropylene resin beads

An expansion-molded article (foamed body) produced by using foamed and expanded beads, and having open voids has sound absorbing qualities, and can be used as a sound absorbing material. A sound absorbing material which is able to attain a high sound absorption coefficient in a wide acoustic frequency range is provided by a molded article produced by using resin particles, having through hole(s) and a porosity of 45 to 80% in a most densely packed state. The void content of the molded article is 10 to 60%, and the bulk density thereof is 0.01 to 0.6 g/cm . The molded article has not less than 3 continuous center frequency measuring points at which the sound absorption coefficient is at least 70%, and not less than 7 continuous center frequency measuring points at which the sound absorption coefficient is at least 50% in the sound absorption coefficients at the center frequencies of 250, 315, 400, 500, 630, 800, 1000, 1250, 1600, 2000, 2500 and 3150 (Hz) as determined by the measuring method of reverberant absorption coefficient prescribed in JIS A 1409.

Molded body of thermoplastic resin having sound absorption characteristics

Foamed and expanded beads including a polyester-based resin containing at least 35 mole % of an aliphatic ester component. The foamed beads have a gel fraction of at least 5 % by weight and comprises at least one gel accelerating agent selected from fatty acids having 12-25 carbon atoms, metal salts of the fatty acids, esters of the fatty acids and amides of the fatty acids in an amount of 0.15-3 % by weight. A foam molding is obtained by heating the foamed and expanded beads in a mold.

Foamed and expanded beads of polyester-based resin and foam molding obtained therefrom

A polycarbonate resin foamed molding having a density D of 0.6 g/cm,or less and at least 30 (kg&middot;cm/cm,)/(g/cm,) of a value E,/D obtained by dividing an amount of energy absorbed through 50% compression of the molding at 80&deg; C. (E,kg&middot;cm/cm,) by the density of the molding. A shock absorber for a vehicle includes a core of the above molding, and a skin covering a surface of the core.

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Yokkaichi, Japan

Mitsuru Shinohara