Kuraray Co., Ltd.

Agc Inc.

Masako Kawagoe

Yosuke Kumaki

Shinsuke Nii

Masato Nakamae

Masaki Kato

Sho Masuda

Yoko Mori

Kazuki Tokuchi

Hideki Maki

Junsuke Kawana

Keishi Hachiya

Kiyofumi Enomoto

The present disclosure relates to a semipermeable membrane. The present disclosure aims to provide a semipermeable membrane having tolerance against a decrease over time in substance permeability. The present disclosure provides a semipermeable membrane containing a resin. The permeation rate of albumin in the semipermeable membrane is no lower than 30%. The albumin adsorption amount obtained when the semipermeable membrane measuring 1 cm on each side is immersed in a 0.1% albumin solution for 90 minutes is no greater than 10 &#x3bc;g/cm. The water permeation amount obtained when water is sucked through the semipermeable membrane at a negative pressure of 3&#xb1;0.2 kPa is expressed by no smaller than 1,000 L/(mhour). The semipermeable membrane can isolate a cell from an external environment.

Semipermeable membrane and method of manufacturing the same

The paper composite contains: a paper substrate having an air permeation resistance of 1,000 sec or less and bulk density of from 0.5 to 1.0 g/cm; and a greaseproof layer on at least one side thereof, the greaseproof layer containing an ethylene-vinyl alcohol polymer (A) and a cationic fluorine-containing polymer (B) having two specific constitutional units. A content of the copolymer (B) in the greaseproof layer is from 5 to 50 parts by mass with respect to 100 parts by mass of the polymer (A), an amount of the greaseproof layer on dry mass basis is from 0.1 to 3.0 g/m, and a water vapor permeability of the paper composite is 1,000 g/m&#xb7;24 h or greater.

Paper composite, packaging material, and production method of paper composite

Provided is greaseproof paper that, when folded, shows little reduction in grease resistance at the folded portion. The greaseproof paper includes a paper base and a greaseproof layer provided on at least one surface of the paper base, wherein the greaseproof layer includes an ethylene-vinyl alcohol-vinyl ester copolymer (A) and a fatty acid derivative (B), contains 1 to 100 parts by mass of the component (B) per 100 parts by mass of the component (A), and is in an amount of 0.5 to 5.0 g/min terms of dry mass. In the greaseproof paper, the ethylene-vinyl alcohol-vinyl ester copolymer (A) has a content of ethylene units of 1 to 15 mol %, has a total content of vinyl alcohol units and vinyl ester units of 85 to 99 mol %, and has a degree of polymerization of 300 to 2000. In the greaseproof paper, the fatty acid derivative (B) is a fatty acid amide compound.

Greaseproof paper having excellent folding resistance

The present invention addresses the problem of providing a composite paper which exhibits excellent oil resistance, water vapor permeability, and water resistance even when hot and oily food is wrapped therein. The above problem can be solved by using a composite paper comprising an oil-resistant layer formed on at least one surface of a base paper, wherein the oil-resistant layer comprises a vinyl alcohol polymer (A) having a content of ethylene units of 2 to 10 mol %, a viscosity-average degree of polymerization of 300 to 2000, a saponification degree of 95 to 99.5 mol %, a total content of carboxyl groups and lactone rings of 0.02 to 3 mol %, a melting point of 180 to 230&#xb0; C., a content of 1,2-glycol bonds of 1.2 to 2 mol %, and a molar fraction of central hydroxyl groups in chains of three consecutive hydroxyls by a triad expression relative to vinyl alcohol units of 65 to 98 mol %, the base paper has an air permeability resistance of 1000 seconds or less and a bulk density of 0.5 to 1.0 g/cm, and the oil-resistant layer is formed in an amount of 0.1 to 10.0 g/min terms of dry mass. The oil-resistant layer may also contain a fluorine compound (B), a layered inorganic compound (C) having an average aspect ratio of 20 to 1000, a fatty acid sizing agent (D), or a cross-linking agent (E).

Composite paper having oil resistance

Provided by the present invention is a PVA having highly harmonized adequate water solubility, thickening property and coating film strength, and having superior storage stability in terms of the viscosity in an aqueous solution. A vinyl alcohol polymer having a ratio (Mw (A)/Mn (A)) of the weight average molecular weight (Mw (A)) to the number average molecular weight (Mn (A)) of 3 or greater and 8 or less, and being capable of giving a vinyl alcohol polymer having a ratio (Mw/Mn) of a weight average molecular weight (Mw) to a number average molecular weight (Mn) of 2 or greater and less than 3 when treated at 40&#xb0; C. for 1 hour in a sodium hydroxide solution.

Vinyl alcohol polymer, thickening agent, stabilizer for emulsion polymerization, stabilizer for suspension polymerization, coating agent, coated article, sizing agent for fibers, sized yarn, and production method of textile

Provided are a vinyl acetal polymer that has sufficient plasticity and solubility in an alcohol solvent, imparts low viscosity, stability, etc., to a solution thereof, is less likely to cause phase separation from other components, and allows for formation of a slurry superior in dispersibility of particles and thixotropic nature, as well as a sheet superior in strength and flexibility, and the like. An alkyl-modified vinyl acetal polymer obtained by subjecting an alkyl-modified vinyl alcohol polymer to acetalization, in which the alkyl-modified vinyl alcohol polymer comprises a monomer unit represented by the following general formula (I), and has a viscosity average degree of polymerization P of 150 or greater and 5,000 or less, a degree of saponification of 20 mol % or greater and 99.99 mol % or less, and a percentage of alkyl modification S with the monomer unit of 0.05 mol % or greater and 5 mol % or less. 

Alkyl-modified vinyl acetal polymer, and composition

There is provided a polyoxyalkylene-modified vinyl acetal polymer which has polyoxyalkylene groups represented by general formula (I) in side chain, in which a viscosity-average polymerization degree P is 150 to 5000, an acetalization degree is 10 to 85 mol % and a polyoxyalkylene modification rate S is 0.1 to 10 mol %. Such a polymer has a feature that a film or sheet produced therefrom has improved film strength and flexibility, as well as a feature that a resin composition therefrom is free from phase separation.  wherein Rrepresents a hydrogen atom or a methyl group, Rrepresents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, and 1&#x2266;m&#x2266;10 and 3&#x2266;n&#x2266;20.

Polyoxyalkylene-modified vinyl acetal polymer, and composition comprising same

Provided is a polyoxyalkylene modified vinyl alcohol-based polymer comprising a polyoxyalkylene group in a side chain, wherein the polymer has a viscosity average degree of polymerization of not less than 150 and not more than 5000, a degree of saponification of not less than 40 mol % and not more than 99.99 mol %, and a polyoxyalkylene group modification rate of not less than 0.05 mol % and not more than 10 mol %; and the polyoxyalkylene group is composed of a polyoxypropylene block and a (poly)oxyethylene block and is represented by the following general formula (I). Such polymer is excellent in temperature-sensitive thickening properties. 

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Kurashiki, Japan

Masako Kawagoe