Kao Corporation

Nec Corporation

Hiroaki Kishimoto

Akira Takenaka

Kazuhiko Inoue

Masatoshi Iji

Shin Serizawa

Yukihiro Kiuchi

Haruomi Enomoto

Tsunenori Yanagisawa

Ryo Shibutani

Yoshiro Oda

Hirofumi Moriwaka

Tadashi Tachinami

A polylactic acid resin composition containing (A) a polylactic acid resin, (B) a plasticizer, (C) an organic crystal nucleating agent, and (D) an acrylic/styrene copolymer having an epoxy group, wherein the above (B) plasticizer is an ester compound having two or more ester groups in the molecule, wherein the ester compound contains one or more members selected from the group consisting of an ester compound in which at least one kind of the alcohol component constituting the ester compound is an alcohol reacted with an alkylene oxide having from 2 to 3 carbon atoms in an amount of from 0.5 to 5 mol on average, per one hydroxyl group, and an ester compound represented by formula (I), and wherein the above (D) acrylic/styrene copolymer having an epoxy group is from 0.1 to 0.9 parts by mass, based on 100 parts by mass of (A) the polylactic acid resin. The polylactic acid resin composition of the present invention can be suitably used in various applications such as wrapping materials for food containers, daily sundries, and household electric appliances, trays for industrial parts, and the like.

Polylactic acid resin composition

A method for producing an injection-molded article of a polylactic acid resin composition, including filling a melt-kneaded product of a polylactic acid resin composition containing a polylactic acid resin, a plasticizer containing a polyoxyalkylene group or an oxyalkylene group, and a mold releasing agent having a melting point of from 20&#xb0; to 75&#xb0; C. in an injection-molding machine to mold in a die, wherein the method is characterized in that the above-mentioned injection-molding machine comprises a cylinder at least a part of which has a set temperature of 200&#xb0; C. or higher, that the die has a surface temperature of 85&#xb0; C. or higher, and that the die has a surface roughness of 1.0 &#x3bc;m or less.

The present invention provides a polylactic acid resin composition, containing a polylactic acid resin and a metal hydrate surface-treated with at least one silane coupling agent selected from an amino-silane coupling agent, a mercapto-silane coupling agent and an isocyanate-silane coupling agent, wherein the content of an alkali metal component in the metal hydrate is not more than 0.2% by mass and a polylactic acid resin molded article produced by molding the polylactic acid resin composition.

The invention relates to a biodegradable resin composition containing a biodegradable resin, a plasticizer and a crystal nucleus agent, the plasticizer being a compound containing two or more ester groups in the molecule thereof, wherein at least one alcohol component constituting the ester contains an alkylene oxide having 2 to 3 carbon atoms, added in the average amount of 0.5 to 5 moles per one hydroxyl group, and the crystal nucleus agent is a mixture of the following crystal nucleus agent (1) and crystal nucleus agent (2); the crystal nucleus agent (1) being the following crystal nucleus agent (1-1) or crystal nucleus agent (1-2): crystal nucleus agent (1-1): at least one selected from compounds having a hydroxyl group and an amide group in the molecule thereof; and crystal nucleus agent (1-2): at least one selected from hydroxy fatty acid esters; crystal nucleus agent (2): at least one selected from a metal salt of phenylphosphonic acid, a metal salt of a phosphate, a metal salt of an aromatic dialkyl sulfonate, a metal salt of rosinic acids, an aromatic carboxylic acid amide, rosinic acid amide, carbohydrazides, N-substituted ureas, salts of melamine compounds and uracils.

Biodegradable resin composition

The present invention provides the method for producing a polylactic acid resin composition, including steps (1) and (2) step (1): adding the polycarbodiimide cross-linking agent to the polylactic acid resin to cross-link the polylactic acid resin; and step (2): mixing the cross-linked polylactic acid resin prepared in the step (1) with the uncross-linked polylactic acid resin.

Method for producing a polylactic acid resin composition

The invention relates to a biodegradable resin composition containing a biodegradable resin, a plasticizer and a crystal nucleus agent, the plasticizer being a compound containing two or more ester groups in the molecule thereof, wherein at least one alcohol component constituting the ester contains an alkylene oxide having 2 to 3 carbon atoms, added in the average amount of 0.5 to 5 moles per one hydroxyl group, and the crystal nucleus agent is a mixture of the following crystal nucleus agent (1) and crystal nucleus agent (2); the crystal nucleus agent (1) being the following crystal nucleus agent (1-1) or crystal nucleus agent (1-2): crystal nucleus agent (1-1): at least one selected from compounds having a hydroxyl group and an amide group in the molecule thereof; and crystal nucleus agent (1-2): at least one selected from hydroxy fatty acid esters; crystal nucleus agent (2): at least one selected from a metal salt of a phosphate, a metal salt of an aromatic dialkyl sulfonate, a metal salt of rosinic acids, an aromatic carboxylic acid amide, rosinic acid amide, carbohydrazides, N-substituted ureas, salts of melamine compounds and uracils.

A method of manufacturing a polylactic acid resin injection molded article, having the step (1): a step of melt-kneading a polylactic acid resin composition containing a polylactic acid resin and a specified organic crystal nucleus agent, while contacting the composition with a supercritical fluid; and step (2): a step of filling the melted product obtained in step (1) in a die to mold with injection-molding. The manufacturing method of the present invention is used as an advantageous technique as compared with the technique of achieving satisfactory moldability by the addition of plasticizer in the field, for example, which requires a polylactic acid resin molded article having high rigidity.

Growing community of inventors

Wakayama, Japan

Hiroaki Kishimoto