Daikin Industries, Ltd.

The Green Cross Corporation

Shunji Kasai

Yasuhiko Sawada

Taku Yamanaka

Makoto Ono

Yoshiyuki Shibuya

Hiroyuki Yoshimoto

Kunihiko Inui

Shinichi Chaen

Masayuki Tsuji

Yoshinori Nanba

Shuji Tagashira

Tetsuo Shimizu

Taketo Kato

Michio Asano

Kazuya Kawahara

Makoto Kobayashi

Hideyuki Kiyotani

Hitoshi Niinuma

Seigo Yamamoto

Masayoshi Miyamoto

Li Bao

Shinichi Yano

Mayumi Yamauchi

Hiroyuki Sato

Takahiro Taira

Hirofumi Arimura

Masanori Morita

Haruhide Kawabe

Toshizumi Tanabe

Ryuji Hiramatsu

Shusei Uno

Masanori Nagai

Yasuo Amatsuji

Masaaki Hirose

A mixed powder and a material for molding have polytetrafluoroethylene as a main component. Each includes polytetrafluoroethylene that can be fibrillated, a non-hot melt processable component that is not fibrillated, and a hot melt processable component with a melting point of lower than 320&#xb0; C. that is not fibrillated. The non-hot melt processable component that is not fibrillated is contained in a range of 20 to 40% by weight of the total weight. The hot melt processable component is contained at equal to or more than 0.1% by weight but less than 20% by weight of the total weight. A drawn porous body includes a plurality of fibrils, and a plurality of knotted portions that are connected to each other by the fibrils.

Mixed powder and material for molding having PTFE as main component, and drawn porous body

A composition, a mixed powder and a material for molding have polytetrafluoroethylene as a main component. Each includes polytetrafluoroethylene that can be fibrillated, a non-hot melt processable component that is not fibrillated, and a hot melt processable component with a melting point of lower than 320&#xb0; C. that is not fibrillated. The hot melt processable component is contained at equal to or more than 0.1% by weight but less than 20% by weight of a total weight. A filtering medium for an air filter includes a porous membrane made of these components, and an air permeable support. The porous membrane is manufactured, by mixing these components, extruding the mixture, rolling and drawing.

Composition having PTFE as main component, mixed powder, material for molding, filtering medium for filter, air filter unit, and a method for manufacturing a porous membrane

Provided is a dripping inhibitor excellent in handling characteristics. The present invention provides a dripping inhibitor including a modified polytetrafluoroethylene, the inhibitor having an average particle size of 300 to 800 &#x3bc;m, an apparent density of 0.40 to 0.52 g/ml, a compression ratio of 1.20 or less, an aggregate disintegration degree with 50-sec vibration of 70% or more, a cylinder extrusion pressure at a reduction ratio 1500 of 80 MPa or less, and a standard specific gravity (SSG) of 2.140 to 2.230.

Dripping inhibitor and resin compound

A filter medium includes a porous film and a support material supporting the porous film. The porous film includes polytetrafluoroethylene, has an average pore diameter of at least 2.5 &#x3bc;m, and has a porosity of at least 95%. A pressure loss is less than 100 Pa when air is passed through the filter medium at a velocity of 5.3 cm/sec. A collection efficiency of NaCl particles is at least 95% when air including NaCl particles with a particle diameter of 0.3 &#x3bc;m is passed through the filter medium at a velocity of 5.3 cm/sec. A PF value is at least 30, where PF={&#x2212;log [(100&#x2212;collection efficiency (%))/100]/pressure loss (Pa)}&#xd7;1000. A dust holding capacity of polyalphaolefin particles held in the filter medium is at least 15 g/mwhen air including polyalphaolefin particles with a count median diameter of 0.25 &#x3bc;m is continuously passed through the filter medium at a velocity of 5.3 cm/sec and pressure loss reaches 300 Pa.

Filter medium equipped with porous film, method of manufacturing same, filter pack, and filter unit

Provided are modified polytetrafluoroethylene particles having excellent moldability and processability. The modified polytetrafluoroethylene particles each have a core-shell structure that includes a particle core and a particle shell, the particle core having repeating units of tetrafluoroethylene and a comonomer (a), the particle shell having repeating units of tetrafluoroethylene and a comonomer (b), the comonomer (a) being a (perfluoroalkyl)ethylene represented by the following formula (I):CH&#x2550;CH&#x2014;Rf&#x2003;&#x2003;(I)

Modified polytetrafluoroethylene particles, method for producing the same, and modified polytetrafluoroethylene molded product

Provided is a material that can be easily biaxially oriented, homogeneously stretched even with a high draw ratio, and formed into a PTFE porous membrane with low pressure loss. The present invention relates to a polytetrafluoroethylene mixture comprising: a fibrillable modified polytetrafluoroethylene; and a fibrillable polytetrafluoroethylene homopolymer, the polytetrafluoroethylene homopolymer having strength at break of 25 N or higher.

Polytetrafluoroethylene mixture

The present invention provides a polytetrafluoroethylene powder having moldability/processability as well as electrical characteristics in microwave bands. The present invention is a modified polytetrafluoroethylene powder which has (1) a dielectric loss tangent at 12 GHz of not higher than 2.0&#xd7;10and (2) a cylinder extrusion pressure of not higher than 45 MPa at a reduction ratio of 1600.

Modified polytetrafluoroethylene powder and method for producing tetrafluoroethylene polymer

Provided is a material that can be easily biaxially oriented, homogeneously stretched even with a high draw ratio, and formed into a polytetrafluoroethylene porous membrane with low pressure loss. The present invention relates to a polytetrafluoroethylene mixture comprising: a modified polytetrafluoroethylene; and a fibrillable polytetrafluoroethylene homopolymer, the modified polytetrafluoroethylene having an extrusion pressure to a cylinder, at a reduction ratio of 1600, of 70 MPa or higher.

The present invention provides a low-molecular weight polytetrafluoroethylene powder that, when used as an additive in a coating material, etc., can form a coating with excellent texture and gliding properties, while also improving dispersibility and viscosity; and a production process therefor. The present invention is a process for producing a low-molecular weight polytetrafluoroethylene powder, the process comprising: an emulsion polymerization step of polymerizing at least tetrafluoroethylene in the presence of a polymerization initiator and an aqueous medium to produce emulsified particles thereof; an agglomeration step of agglomerating the emulsified particles to form an agglomerated powder thereof; and a suspension polymerization step of polymerizing at least tetrafluoroethylene in the presence of the agglomerated powder, a polymerization initiator, and an aqueous medium.

Low molecular weight polytetrafluoroethylene powder and preparation method therefor

The invention provides a TFE polymer capable of providing stretched materials excellent in membrane homogeneity. The present invention is related to a tetrafluoroethylene polymer having stretchability and non-melt-processability and having a standard specific gravity of 2.140 to 2.165, wherein, with regard to the heat-of-fusion curve obtained by subjecting the tetrafluoroethylene polymer in the form of an unbaked polymer to be measured having no history of being heated to a temperature of 300&#xb0; C. or higher to differential scanning calorimetry at a programming rate of 2&#xb0; C./minute, the ratio S/Sis not lower than 0.90.

Tetrafluoroethylene polymer and aqueous dispersion thereof

The present invention provides a molded article comprising a polytetrafluoroethylene resin (A) and a thermoplastic resin (B) having a melting point of not lower than 100&#xb0; C. but lower than 322&#xb0; C., wherein the maximum peak temperature of the endothermic curve appearing on the crystal melting curve of the above polytetrafluoroethylene resin (A) as measured by a differential scanning calorimeter is higher by at least 3&#xb0; C. than the maximum peak temperature of the endothermic curve appearing on the crystal melting curve of the above polytetrafluoroethylene resin (A) after heating to a temperature of not lower than 340&#xb0; C. as measured by the differential scanning calorimeter.

Molded object process for producing the same product for high-frequency signal transmission and high-frequency transmission cable

It is an object of the present invention to provide a polytetrafluoroethylene-based-resin tube high in longitudinal tensile strength and a method of producing the same. The present invention provides a polytetrafluoroethylene-based-resin tube characterized in that the tensile strength thereof in the longitudinal direction is not lower than 60 MPa.

Polytetrafluoroethylene-based-resin tube and production method thereof

The present invention provides a polytetrafluoroethylene molded article, particularly a PTFE molded article for high-frequency insulation, which is excellent in various electric properties and mechanical properties in a high frequency range of 3 to 30 GHz. The present invention also provides PTFE fine powder, which is excellent in extrusion moldability and capable of providing the molded article, and a process for preparing the same. More specifically, the present invention relates to a polytetrafluoroethylene fine powder having a standard specific gravity of 2.180 to 2.225, which is obtained by contacting polytetrafluoroethylene fine powder having a standard specific gravity of 2.180 to 2.225 with a fluorine radical source, wherein tan&#x3b4; at 12 GHz of a film comprising the powder, which is obtained by cooling at 5 to 50&#xb0; C./second after baking, is at most 2.0&#xd7;10.

Polytetrafluoroethylene fine powder of particular specific standard gravity, polytetrafluoroethylene formed article prepared from the same and method for preparation of the same

The present invention provides a TFE resin molding material which has electric characteristics, particularly low dielectric dissipation factor, in a microwave area, can also lower extrusion pressure as the material is of low molecular weight and can provide a molded article excellent in surface smoothness. The material is especially useful as a coating material for a coaxial cable for equipment in which microwave is used, including satellite transmitting equipment and a cell phone base station. A tetrafluoroethylene resin molding material excellent in high frequency electric characteristics, which provides a molded article having a dielectric constant of at most 2.2 and a dielectric dissipation factor of at most 1.60&#xd7;10under 12 GHz, and a standard specific gravity of at least 2.192 and less than 2.3 is provided. As the tetrafluoroethylene resin, a tetrafluoroethylene homopolymer or a copolymer of 99.9 to 99.9999% by mole of tetrafluoroethylene and 0.0001 to 0.1% by mole of a specific fluoromonomer is used.

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Settsu, Japan

Shunji Kasai