Tokuyama Soda Kabushiki Kaisha

Shunichi Nakamura

Satoshi Nagou

Shingo Kaneko

Yukio Mizutani

Kazuo Shikata

Michio Yoshimizu

Kenji Okamura

Kaneko Shingo

Hisashi Nakanishi

Tomoyasu Kawamura

Takeshi Nishibayashi

Kiyoshi Sumi

Disclosed is a microporous shaped polyolefin article comprising a polyolefin and synthetic resin particles dispersed therein and having a softening temperature or a decomposition temperature higher than the shaping temperature of the polyolefin resin, said article having a network structure composed of open-cellular pores with a maximum pore diameter of not more than 5 micromoters, having a porosity of 20 to 90% and being molecularly oriented by stretching. A process for its production is also provided.

Microporous shaped article and process for preparation thereof

Disclosed is a microporous polyproplene film comprising a propylene homopolymer, a copolymer of propylene with other copolymerizable monomer or a blend thereof, which has an intrinsic viscosity (.eta.) of 1.9 to 3.0 dl/g, especially 2.0 to 3.0 dl/g, as measured at 135.degree. C. in tetralin, said microporous film having a network structure comprising intercommunicating pores having a maximum pore size smaller than 1.mu. and an average pore size of 0.005 to 0.6.mu. and having a porosity of 30 to 90%, an air permeability of 5 to 500 sec/100 cc and a thickness of 5 to 200.mu., said microporous film being molecularly oriented by stretching.

Microporous film and process for production thereof

A porous sheet having a good softness and being excellent in moisture permeability, water resistance and mechanical strength characteristics such as tensile strength and tear strength is obtained by forming into a sheet a composition comprising 100 parts by weight of a polyolefin resin, 50 to 400 parts by weight of a filler and 0.1 to 10 parts by weight of a silicone oil, and drawing the sheet.

Process for preparation of porous sheets

A stretching device for stretching a tubular film includes a mandrel including a stretching section, a pair of payoff nip rolls disposed upstream of the mandrel and a pair of take-up nip rolls disposed downstream of the mandrel. The stretching section of the mandrel is comprised of a plurality of rings arranged substantially concentrically in spaced-apart relationship in the travelling direction of the tubular film. The outside diameter of a ring on the downstream side is larger than that of a ring on the upstream side. Each of the rings has a plurality of rotating members mounted rotatably, and the plurality of rotating members define an outer circumferential ring edge which is generally smoothly circular.

Stretching device for stretching tubular film

A process for the preparation of soft porous sheets, comprises forming into a sheet a composition comprising (i) 40 to 80% by weight of an inorganic filler and (ii) 60 to 20% by weight of a polyolefin type thermoplastic elastomer composition comprising at least 50% by weight of a polyolefin type thermoplastic elastomer substantially free of a polar group, in which the tensile stress at a temperature of 25.degree. C. under 100% stretching (100% modulus) is 10 to 100 Kg/cm.sup.2, the elongation at break under stretching is at least 100% and the permanent strain under 100% stretching is less than 50% and up to 50% by weight of a thermoplastic plastomer, and stretching the sheet at a temperature lower than the softening temperature of the polyolefin type thermoplastic elastomer. A porous sheet obtained according to this process has a good combination of flexibility, air permeability and water resistance.

Porous sheet

A process for producing flame-retardant shaped articles of thermoplastic synthetic resins is disclosed which process comprises dispersing homogeneously in a thermoplastic synthetic resin an inorganic metal compound and a surfactant, said inorganic metal compound being one capable of forming a hydrate by reacting with a member of the group consisting of water and an aqueous acid solution, forming the resulting composition into a desired shaped article, and thereafter contacting the thus obtained shaped article with a member selected from the group consisting of water and an aqueous acid solution, thereby converting said inorganic metal compound contained in said shaped article to a hydrate.

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Hikari, Japan

Shunichi Nakamura