Kureha Kagaku Kogyo K.k.

Kureha Kagaku Kogyo Kabushiki Kaisha

Kureha Corporation

Other

Polyplastics Co., Ltd.

Kureha Chemical Industry Company, Limited

Kureha Kagaku Kagyo K.k.

Yukichika Kawakami

Zenya Shiiki

Mitsuru Hoshino

Toshitaka Kouyama

Nobuo Sato

Hiroyuki Sato

Kazuyuki Yamane

Yo Iizuka

Takayuki Katto

Yoshikatsu Satake

Takao Iwasaki

Takashi Sato

Ken Kashiwadate

Fuminori Kobayashi

Kazuhiko Sunagawa

Makoto Fukuda

Toshio Hosokawa

Hajime Hoshi

Masahiro Segawa

Tomohiro Hoshi

Yoshikazu Amano

Masayuki Niwa

Sirou Suzuki

Shuji Morinishi

Morio Shirai

Kazuyuki c/o Nishiki Res Lab Yamane

Hiroyuki Nishiki Res Lab Sato

Yoshikazu c/o Kureha Corporation Amano

Takashi c/o Packaging Materials Sato

Fuminori c/o Research Center Kobayashi

Hiroyuki c/o Research Center Sato

Kazuyuki c/o Research Center Yamane

A human healing ability enhancing apparatus includes an airtight part that is capable of being airtight; a decompression pump that decompresses air pressure in the airtight part and communicates with an exhaust port of the airtight part; and an over-decompression prevention device for preventing over-decompression in which the air pressure in the airtight part is lower than a predetermined threshold air pressure.

Human healing ability enhancing apparatus and method for actuating human healing ability enhancing apparatus

In the production of an aliphatic polyester by ring-opening polymerization of a cyclic ester, at least a latter period of polymerization is proceeded with by way of solid-phase polymerization, and the resultant aliphatic polyester is subjected to removal of residual cyclic ester. As a result, an aliphatic polyester with a minimized content of residual monomer is obtained.

Process for producing aliphatic polyester reduced in residual cyclic ester content

The invention relates to a glycolide production process wherein a depolymerization reaction system comprising a glycolic acid oligomer or a glycolic acid oligomer and a polar organic solvent is heated to depolymerize the glycolic acid oligomer into glycolide, the resulting glycolide or the glycolide and polar organic solvent are distilled out of the depolymerization reaction system, and the glycolide is recovered from distillates obtained by distillation. The glycolic acid oligomer or the glycolic acid oligomer and polar organic solvent are continuously or intermittently charged into the depolymerization reaction system, thereby carrying out depolymerization reactions continuously or repeatedly. During the depolymerization reactions, a compound having an alcoholic hydroxyl group is permitted to exist at a specific quantitative ratio in the depolymerization reaction system. The invention is also concerned with a glycolic acid oligomer for the production of glycolide, which is obtained by condensation of glycolic acid in the presence of the compound having an alcoholic hydroxyl group.

Glycolide production process, and glycolic acid oligomer for glycolide production

A polyglycolic acid-based resin composition is formed by adding a relatively small amount of aromatic polyester resin to a polyglycolic acid resin. The thus-formed composition is provided with remarkably improved moisture resistance stability and hot-melt processability, and further improved stretchability, while retaining the excellent properties as represented by gas barrier property of the polyglycolic acid resin. As a result of stretching by utilizing the improved stretchability, a shaped product having an improved transparency can be obtained.

Polyglycolic acid-based resin composition and shaped product thereof

Polyhydroxycarhoxylic acids are provided, which are controlled in terms of the rate of biodegradability, and give molded or otherwise formed articles that are of uniform quality with neither premature strength drop nor premature deterioration of retention of outside shape, and their production process is provided as well. The poly-hydroxycarboxylic acids are obtained by ring-opening polymerization of cyclic esters. The polyhydroxy-carboxylic acids have a weight-average molecular weight (Mw) in the range of 10,000 to 1,000,000, a molecular weight distribution in the range of 1.0 to 2.5 as represented by the weight-average molecular weight-to-number-average molecular weight ratio (Mw/Mn) and a yellowness index (YI) of 40 or less, and have a precisely controlled rate of biodegradability.

Polyhydroxycarboxylic acid and its production process

The present invention provides a process for production of a cyclic ester by depolymerization of an aliphatic polyester. In the process, a mixture containing the aliphatic polyester and a specific polyalkylene glycol ether, which has a boiling point of 230-450&#xb0; C. and a molecular weight of 150-450, is heated under normal or reduced pressure to a temperature at which depolymerization of the aliphatic polyester takes place. Then, a substantially homogeneous solution phase, consisting of the melt phase of the aliphatic polyester and the liquid phase of the polyalkylene glycol ether, is formed. Heating of the solution phase is continued to form the cyclic ester by depolymerization and distil out the cyclic ester together with the polyalkylene glycol ether, and then the cyclic ester is recovered from the distillate. The present invention also provides a process for purification of a crude cyclic ester by use of the specific polyalkylene glycol ether described above.

Process for the preparation of cyclic esters and method for purification of the same

The invention provides a process for producing glycolide by depolymerization by heating of a glycolic acid oligomer in the presence or absence of a solvent, which process ensures stable depolymerization. The depolymerization reaction is carried out while the content of alkaline metal ions in a glycolic acid oligomer-containing depolymerization reaction system is controlled to 0.001% by mass or lower; a sulfate or an organic acid salt, each in the form of di- or poly-valent cations, or a mixture thereof is allowed to be present as a stabilizer in the depolymerization reaction system; or the content of alkaline metal ions in the depolymerization reaction system is controlled to 0.001% by mass or lower, and a sulfate or an organic acid salt, each in the form of di- or poly-valent cations, or a mixture thereof is allowed to be present as a stabilizer in the depolymerization reaction system.

Glycolide production process, and glycolic acid composition

The invention provides a polyester production process by bulk polymerization in a reactor, wherein the volume of the resulting polyester is shrunk for a release from the inner surface of the reactor, so that the polyester can be recovered in the form of a bulky mass. The invention also provides a reactor for bulk polymerization for polyester, which comprises an inner surface that enabling the resulting polyester to be released therefrom upon its volume shrinkage.

Polyester production process and reactor apparatus

Gas-barrier, multi-layer hollow container

A composite gas barrier film having a layer structure comprises a thermoplastic resin film laminated on at least one side of a film formed from polyglycolic acid containing at least 60 wt. % of a repeating unit represented by the following formula (1):

Gas-barrier composite film

The invention provides an injection-molded product of polyglycolic acid obtainable by molding a thermoplastic resin material at an injection temperature ranging from the melting point, Tm of the polymer to 255&deg; C., wherein the thermoplastic resin material comprises polyglycolic acid having a repeating unit represented by the following formula (1):

Production process for injection-molded product of polyglycolic acid

The invention provides a stretch blow molded container formed from a thermoplastic resin material which comprises polyglycolic acid having (a) a repeating unit represented by the following formula (1): ##STR1## (b) a melt viscosity, .eta.* [as measured at a temperature of (the melting point, Tm of the polymer+20.degree. C.) and a shear rate of 100/sec] of 500-100,000 Pa.s; (c) a melting point, Tm of at least 180.degree. C.; (d) a melt enthalpy, .DELTA.Hm of at least 20 J/g; and (e) a density of at least 1.50 g/cm.sup.3 as measured in an unoriented, crystallized form, wherein the stretch blow molded container has tensile strength (in a circumferential direction) of at least 100 MPa and a carbon dioxide permeability (as measured at a temperature of 23.degree. C. and 80% relative humidity; in terms of the thickness of 50 .mu.m) of 300 cc/m.sup.2.day.atm or smaller at the body sidewall thereof, and a production process thereof.

Stretch blow molded container and production process thereof

An injection-molded product is obtained by injection molding a thermoplastic resin material. The thermoplastic resin material comprises a polyglycolic acid homopolymer or copolymer having a repeating unit represented by the following formula (1): ##STR1## in a proportion not lower than 70 wt. % and a repeating unit derived from at least one cyclic comonomer selected from the group consisting of ethylene oxalate and lactide in a proportion not higher than 30 wt. %, and having the following physical properties: (a) a melt viscosity, n*, measured at a temperature of the melting point, Tm, of the polyglycolic acid homopolymer or copolymer +20.degree. C. and a shear rate of 1,000/sec, of 30-10,000 Pa.multidot.s; (b) a melting point, Tm, of at least 150.degree. C.; (c) a melt enthalpy, .DELTA.Hm, of at least 20 J/g; and (d) a density of at least 1.50 g/cm.sup.3 as measured in an unoriented, crystallized form. The injection-molded product has Izod impact strength, unnotched, 25.degree. C., of at least 20 kJ/m.sup.2, tensile strength of a least 60 MPa, tensile elongation of at least 5%, flexural strength of at least 100 MPa, and flexural modulus of at least 5 GPa, and is obtained by injection molding at an injection temperature ranging from the melting point, Tm, of the homopolymer or copolymer to 255.degree. C.

Injection-molded product of polyglycolic acid and production process

The invention provides a stretch blow molded container formed from a thermoplastic resin material which comprises polyglycolic acid having

The invention provides a polyglycolic acid sheet obtainable by melt-extruding a thermoplastic resin material into a sheet in a temperature range of from the melting point, Tm of the polymer to 255.degree. C., wherein the thermoplastic resin material comprises polyglycolic acid having a repeating unit represented by the following formula (1): ##STR1## and the following physical properties: (a) the melt viscosity, .eta.* �as measured at a temperature of (the melting point, Tm of the polymer+20.degree. C.) and a shear rate of 100/sec! being 500-100,000 Pa.s;

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Fukushima, Japan

Yukichika Kawakami