Jsp Corporation

Akinobu Hira

Hisao Tokoro

Hidehiro Sasaki

Keiichi Hashimoto

Shota Takagi

Satoru Shioya

Mitsuru Shinohara

Hiroshi Yamazaki

Tomoo Tokiwa

Tatsuya Hayashi

Tokunobu Nohara

Takumi Sakamura

Kazutoshi Sasaki

Naoki Mochida

Kazuya Ogiyama

Hiroki Yanagisawa

A molded article of polyolefin-based resin expanded beads having excellent appearance and further suppressed color unevenness is provided. Polyolefin-based resin expanded beads obtained by expanding polyolefin-based resin particles including one or two or more metal borates selected from zinc borate and magnesium borate, wherein the particles of the metal borate has an arithmetic average particle diameter based on the number of 1 μm or more, and a number rate of the particles of the metal borate having a particle diameter of 5 μm or more is 20% or less. A method for producing polyolefin-based resin expanded beads by releasing expandable polyolefin-based resin particles containing one or two or more metal borates selected from zinc borate and magnesium borate and a physical blowing agent dispersed in an aqueous medium in a closed vessel together with the aqueous medium from the closed vessel to a low pressure region than an inside of the closed vessel to expand the expandable polyolefin-based resin particles, the method comprising: using a metal borate having an arithmetic average particle diameter based on the number of 1 μm or more and a number rate of the particles having a particle diameter of 5 μm or more of 20% or less as the metal borate.

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

The present invention relates to cylindrical expanded thermoplastic elastomer beads provided with through-holes, the expanded thermoplastic elastomer beads including a core layer in an foamed state constituted of a base polymer containing a thermoplastic elastomer and a cover layer covering the core layer and constituted of a thermoplastic polymer, wherein a coefficient of dynamic friction of the thermoplastic polymer is 0.8 or less, and a difference between a melting point (Tmc) of the base polymer and a melting point (Tms) of the thermoplastic polymer is −20° C. or more and 20° C. or less. The present invention also relates to an expanded thermoplastic elastomer beads molded article formed by subjecting expanded thermoplastic elastomer beads provided with through-holes to in-mold molding, the molded article including a core layer in a foamed state and a cover layer covering the core layer, wherein a voidage is 15% or more, a density is 10 kg/mor more and 200 kg/mor less, and the product of a tensile strength (MPa) and a tensile elongation (%) is 5 or more.

Thermoplastic elastomer foam particles and molded body of same

A polyamide-based resin expanded bead comprising a foam layer formed by expanding a polyamide-based resin, wherein on a first DSC curve and a second DSC curve, the first DSC curve has a melting peak (intrinsic peak) having a peak top temperature on a low temperature side equal to or lower than a peak top temperature of a melting peak of the second DSC curve and a melting peak (high temperature peak) having a peak top temperature on a high temperature side exceeding the peak top temperature of the second DSC curve, and, the peak top temperature of the melting peak of the second DSC curve is 180° C. or higher and 280° C. or lower, and the polyamide-based resin expanded bead has an apparent density of 10 to 300 kg/mand a closed cell ratio of 85% or more.

Polyamide resin foamed particles and method for producing same

Expanded beads are those including a mixture of an olefin-based thermoplastic elastomer and a polyethylene-based resin, wherein a melt flow rate MFR(I) of the olefin-based thermoplastic elastomer is 2-10 g/10 min; a difference ((MFR(II))−(MFR(I))) between a melt flow rate MFR(II) of the polyethylene-based resin and the melt flow rate MFR(I) of the olefin-based thermoplastic elastomer is 1-35 g/10 min; and a content of the polyethylene-based resin in the mixture is 3-40% by weight.

Foam particles

A laminated article includes a thermoplastic resin expanded beads molded layer A having a volume Va and a tensile modulus TMa which is 2 to 100 MPa, and a thermoplastic elastomer expanded beads molded layer B having a volume Vb and a tensile modulus TMb which is 0.05 MPa or more and less than 2 MPa, the layers A and B being laminated and bonded to each other. Va:Vb is 90:10 to 50:50 and TMb/TMa is 0.025 or less.

Laminated article

An inorganic filler-containing, polyolefin-based resin expanded bead having an expanded core layer of a first polyolefin-based resin, and a cover layer of a second polyolefin-based resin that covers the expanded core layer, wherein a weight ratio of the cover layer to the expanded core layer is 1:99 to 20:80, the expanded core layer contains an inorganic filler in a weight percentage amount of 5 to 90%, and the cover layer contains no inorganic filler or contains an inorganic filler in a weight percentage amount lower than that in the expanded core layer.

Polyolefin-based resin expanded beads comprising inorganic fillers

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 and process of producing expanded polypropylene resin beads

Process of producing foamed molding from expanded polypropylene resin beads

A process for the production of expanded beads, including kneading a base resin containing a polypropylene resin and having a tensile modulus of at least 1,200 MPa together with a mixture of a coloring agent and a thermoplastic polymer having a tensile modulus lower than that of the base resin to form a kneaded mixture including a matrix of the base resin and a multiplicity of domains dispersed in the matrix and each containing the thermoplastic polymer and the coloring agent. The kneaded mixture is formed into resin particles, then treated with an organic peroxide to modify surfaces of the resin particles therewith. Foaming and expanding of the surface-modified resin particles gives expanded beads having an inside region surrounded by a surface region. The heat of fusion of a high temperature peak of the surface region is lower than that of the inside region.

Expanded polypropylene resin beads and process for the production thereof

A composite foamed polypropylene resin molding including a plurality of sections which are fuse-bonded to each other, at least two of which differ from each other in color, apparent density, composition and/or mechanical strengths, each of which is formed from expanded polypropylene resin beads, and each of which shows a high temperature endothermic peak in a DSC curve thereof. At least one of the sections satisfies conditions (d) to (f) at the same time: (d) to be formed from specific expanded polypropylene resin beads of a base resin having a tensile modulus of at least 1,200 MPa, (e) to have an apparent density Dof 10&#x2013;500 g/L, and (f) to have such a high temperature endothermic peak with a calorific of EJ/g, wherein Dand Ehave the relationship 20&#x2212;0.020&#xd7;D&#x2266;E&#x2266;65&#x2212;0.100&#xd7;DThe composite molding may be prepared by filling expanded polypropylene resin beads in each of a plurality of contiguous spaces defined in a mold cavity and heating the expanded beads to fuse-bond respective expanded beads together into a unitary body. At least one of the spaces is filled with the specific expanded polypropylene resin beads.

Composite foamed polypropylene resin molding and method of producing same

Expanded, substantially non-crosslinked polypropylene resin beads capable of producing a high rigidity foamed molding at a relatively low temperature. The beads are produced by a process including a step of dispersing substantially non-crosslinked polypropylene resin particles in a dispersing medium containing an organic peroxide to obtain a dispersion, a step of heating the dispersion to decompose the organic peroxide and to modify the surface of the surface-modified polypropylene resin particles, and a step of expanding the non-crosslinked, surface-modified polypropylene resin particles using a blowing agent.

Expanded polypropylene resin bead and process of producing same

A method for producing expanded polypropylene resin particles wherein polypropylene resin particles impregnated with a physical blowing agent are heated along with an aqueous medium and a dispersant and are released and expanded at reduced pressure from the interior of a pressure-tight vessel, wherein the aforementioned aqueous medium has an electrical conductivity of from not less than 0.00 ms/m to not more than 20.00 mS/m. The resulting particles obtained are without inconsistencies caused by differences in the amount of dispersant adhering to the particles or the amount of dispersant added to prevent the particles from fusing together during the heat treatment step of the method.

Production method of foamed 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

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.

Polycarbonate resin foam and shock absorber using the same

Disclosed herein is an molded article of foamed and expanded beads of a propylene resin, which is obtained by heating and molding the foamed beads of the propylene resin, wherein the apparent density of the molded article is 0.11 to 0.45 g/cm.sup.3, a value obtained by dividing its maximum bending strength (kgf/cm.sup.2) determined in accordance with JIS K 7221 by the apparent density (g/cm.sup.3) is at least 160 (kgf/cm.sup.2)/(g/cm.sup.3), and the average number of cells at its section is within a range of 5 to 100 cells/mm.sup.2.

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Kanuma, Japan

Akinobu Hira