JP2008037939A - Lactic acid resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin composition that can productively afford a heat-resistant molded product composed of a lactic acid resin composition and its manufacturing method. <P>SOLUTION: The lactic acid resin composition comprises 100 pts.wt. of a lactic acid resin (A), and incorporated therewith, 0.1-50 pts.wt. of a crystal nucleating agent (B) and 1-15 pts.wt. of a crystallization promoting agent (C) having a melting point of 60-130°C. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a resin composition in which a specific compound is added as a lactic acid resin, a crystal nucleating agent and a crystallization accelerator to accelerate the crystallization speed, a method for producing the composition, and a molding produced thereby. About the body. More specifically, the present invention relates to a molded product having a short molding cycle and good productivity and excellent heat resistance, and a molding method thereof.

  As awareness of global environmental issues increases, fossil raw materials, petroleum resources are depleted, and carbon dioxide is increasing. Polylactic acid having excellent moldability has attracted attention as a plant-derived resin that uses lactic acid obtained by fermentation from cereal resources such as corn as a raw material.

  However, although polylactic acid is a crystalline resin, its crystallization rate is remarkably slow, and although the melting point of crystalline polylactic acid is as high as 160-180 ° C, the heat resistance of amorphous polylactic acid is low because of its glass transition point of 58 ° C. There was a drawback that the heat-resistant deformation temperature was as low as less than 60 ° C., and there was a limit to application development. Improvement of these lactic acid-based resins is desired for use in everyday environments.

  As a technique for improving the heat resistance, there is a method of highly crystallizing by heat treatment at the time of molding or after molding. However, the method of crystallizing at the time of molding is not practical because the crystallization rate of polylactic acid is slow and the holding time in the mold is required for a long time, resulting in poor production efficiency.

Further, the method of crystallizing after molding has some problems such as deformation because it takes a long time to crystallize in the process of crystallizing by heat treatment.
Several methods for increasing the crystallization speed have been disclosed for such problems.

In Patent Document 1, poly (3-hydroxybutyrate / poly-3-hydroxyvalerate copolymer, polycaprolactone or polylactic acid, biodegradable plastic, calcium carbonate having an average particle size of 20 μm or less, and talc are added. It is described that 10-40% is mixed.
This technique promotes the decomposition of biodegradable plastics by adding a large amount of inorganic filler, and is not a technique for improving heat resistance by crystallizing a polymer.

Patent Document 2 describes that a crystalline inorganic powder containing 50% or more of silica, such as talc, is added to a lactic acid-based polymer and injection molded into a mold having a mold temperature of 85 to 125 ° C. Further, it is described that without the dispersant, the crystallization agent is locally dispersed because the dispersion of the crystal nucleating agent is poor, and the molded product is brittle, so that a molded product that can withstand practical use cannot be obtained.
In the examples, the molded product obtained by crystallization at a mold temperature of about 100 to 110 ° C. at the time of injection molding is a heat-resistant molded product, but the molding cycle needs a long cooling time of 30 seconds, and There is a problem that the molded product is deformed when it is taken out from the mold, and it cannot be said that it is a sufficient technique yet.

  Patent Document 3 discloses a composition in which a lactic acid polymer is mixed with a phosphoric acid ester metal salt and a basic inorganic aluminum compound. In the examples, the composition is injection molded in a mold maintained at 100 ° C. And holding for 45 seconds (cooling time) to obtain the obtained JIS physical property evaluation test piece, and further, it is disclosed that the deflection temperature becomes 100 ° C. or more as an index of heat resistance. However, this method also requires a long cooling time, and the productivity is not practical.

Patent Document 4 describes a method in which a resin composition composed of whiskers is melted in a lactic acid-based polymer, filled in a mold set at a temperature higher than the glass transition temperature in DSC and lower than the melting start temperature, and molded while crystallizing. ing.
In the examples, it is described that the mold temperature of the composition was set to 100 ° C., the solidification time was kept at 45 seconds, and a test piece was obtained by injection molding. Even this method requires a long cooling time, and the productivity is not practical.

Thus, although a method of adding and crystallizing an inorganic crystal nucleating agent such as talc, phosphate metal salt, whisker or the like to improve the heat resistance of polylactic acid is disclosed, the crystallization rate of polylactic acid is Since it is extremely slow, the time required for crystallization is long, and the fact is that the molding cycle is long and the productivity is poor.
Japanese Patent Application Laid-Open No. 5-70696 JP-A-8-193165 JP 2003-192883 A JP 2003-231799 A

  The problem to be solved by the present invention is to improve the crystallization speed of the lactic acid resin composition, and in a molding method such as injection molding, vacuum molding, blow molding, etc., it is crystallized at the time of molding or after molding and heat-resistant molding It is to develop a technology for obtaining products in a normal molding cycle.

  In the present invention, 0.1 to 50 parts by weight of the crystal nucleating agent (B) and 1 to 15 parts by weight of a crystallization accelerator (C) having a melting point of 60 to 130 ° C. with respect to 100 parts by weight of the lactic acid resin (A). A lactic acid resin composition comprising

  The lactic acid resin composition, wherein the crystallization accelerator (C) is one or a mixture of two or more selected from amide compounds, alcohol compounds, carboxylic acid compounds, and ester compounds, is a preferred embodiment of the present invention. It is.

The lactic acid resin composition in which the crystal nucleating agent (B) is a crystalline inorganic compound containing 50% or more of SiO ₂ component is also a preferred embodiment of the present invention.

  The lactic acid resin composition wherein the crystal nucleating agent (B) is selected from the group consisting of talc, clay, kaolinite, kaolin clay and silicic acid compound is also a preferred embodiment of the present invention.

  A lactic acid resin composition comprising 1 to 50 parts by weight of a thermoplastic resin (D) having a heat distortion temperature measured by a method according to ASTM D-648 of 70 ° C. or more in 100 parts by weight of the lactic acid resin composition This is a preferred embodiment of the present invention.

  The lactic acid resin composition wherein the thermoplastic resin fat (D) is at least one or a mixture of two or more from the group consisting of polypropylene, polycarbonate, acrylonitrile-styrene copolymer, and acrylonitrile-butadiene-styrene copolymer. This is a preferred embodiment of the present invention.

  Also provided is a method for producing a molded body, characterized in that the lactic acid resin composition is crystallized at or after molding in a temperature range of glass transition temperature (Tg) to melting point (Tm) of the lactic acid resin composition. To do.

  Inserting the lactic acid resin composition into a mold maintained at a temperature from the crystallization start temperature to the crystallization end temperature of the lactic acid resin composition, followed by crystallization as it is, to produce a molded article A method is also provided.

The lactic acid resin composition is once cooled and solidified to obtain an amorphous molded body, and then the resin composition is heat treated at a temperature of (glass transition temperature (Tg) +10) ° C. to (melting point (Tm) −20) ° C. Then, a method for producing a molded article, characterized by being crystallized, is also provided.
A molded body obtained by the production method is also provided.

  According to the present invention, a molded product of a heat-resistant lactic acid resin composition can be obtained with high productivity.

Hereinafter, the present invention will be described in detail.
[Lactic acid resin]
In the present invention, the lactic acid-based resin (A) means a polymer containing L-lactic acid and / or D-lactic acid as a main constituent and a polymer composition containing it as a main component. It refers to a polymer composition whose main component is a polymer containing at least 50 mol% or more, preferably 60 mol% or more, more preferably 75 mol% or more, and most preferably 80% or more.

  When the lactic acid resin is a copolymer, lactic acid, other hydroxycarboxylic acid, a copolymer comprising at least a lactic acid component consisting of a polyvalent carboxylic acid and a polyhydric alcohol (for example, a copolymer of lactic acid and glycolic acid, a copolymer of lactic acid and caproic acid, etc. And block copolymers of polylactic acid and polybutylene succinate). The arrangement of the copolymer may be any of random copolymer, alternating copolymer, block copolymer, graft copolymer and the like.

  Furthermore, these may be at least partially crosslinked with a polyvalent isocyanate such as xylylene diisocyanate or 2,4-tolylene diisocyanate or a crosslinking agent such as cellulose, polysaccharides such as acetyl cellulose or ethyl cellulose. At least a part may take any structure such as a linear shape, a circular shape, a branched shape, a star shape, or a three-dimensional network structure, and there is no limitation.

  Synthesized by polycondensation of lactic acid or ring-opening polymerization of lactide, a cyclic dimer of lactic acid, with other monomers copolymerizable with lactic acid within a range that does not significantly impair the properties of the polymer, etc. A composition in which a resin, an additive and the like are mixed may be used.

  Of the lactic acid resins (A), polylactic acid is preferred. When the component of the L-form or D-form increases as polylactic acid, the heat resistance and the like are improved, so the amount of the L-form is 90 mol% or more, more preferably 95 mol% or more, and most preferably 98 mol% or more. . Alternatively, the amount of Form D is 90 mol% or more, more preferably 95 mol% or more, and most preferably 98 mol% or more.

  Monomers that can be copolymerized with lactic acid include hydroxycarboxylic acids (eg, glycolic acid, caproic acid, etc.), aliphatic polyhydric alcohols (eg, butanediol, ethylene glycol, etc.) and aliphatic polycarboxylic acids (eg, succinic acid). Acid, adipic acid, etc.). When the lactic acid resin (A) is a copolymer, the copolymer may be arranged in any manner such as a random copolymer, an alternating copolymer, a block copolymer, and a graft copolymer. Furthermore, these are at least partially ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, ethylene glycol / propylene glycol copolymer, 1,3-butanediol, 1,4-butanediol. , Polyfunctional alcohols such as 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,9-nonanediol, neopentyl glycol, polytetramethylene glycol, glycerin, trimethylolpropane, etc. , Polyisocyanates such as xylylene diisocyanate, 2,4-tolylene diisocyanate, etc., and polysaccharides such as cellulose, acetyl cellulose, ethyl cellulose and the like may be copolymerized. Some and also has a linear, cyclic, branched, star-shaped, three-dimensional network structure, any structure may take the equal, there is no limit.

  As a method for producing the lactic acid-based resin (A), a publicly known method can be used, for example, a method of directly dehydrating polycondensation of the raw materials, or a cyclic dimer of the lactic acid or hydroxycarboxylic acid, for example, lactide, It can be obtained by ring-opening polymerization of a cyclic ester intermediate such as glycolide or ε-caprolactone.

  When producing by direct dehydration polycondensation, the raw materials lactic acid or lactic acids and hydroxycarboxylic acids, aliphatic dicarboxylic acids and aliphatic diols are preferably azeotroped in the presence of an organic solvent, particularly a phenyl ether solvent. Polymerization is carried out by a method of dehydrating and condensing, particularly preferably removing the water from the azeotropic solvent to return the solvent to a substantially anhydrous state.

The weight average molecular weight (Mw) of the lactic acid resin (A) is preferably from 50,000 to 1,000,000, more preferably from 50,000 to 500,000, and even more preferably from 70,000 to 30. 10,000 or less, and most preferably 100,000 or more and 300,000 or less. Within this range of weight average molecular weight, heat resistance, strength, moldability, and processability are good.
Further, the molecular weight distribution (Mw / Mn) is usually 2 or more and 15 or less, and a more preferable molecular weight distribution range is 2 or more and 10 or less, and more preferably 2 or more and 8 or less. The weight average molecular weight (Mw) and the number average molecular weight (Mn) shown in the present invention having good heat resistance, strength, moldability, and workability within this molecular weight distribution range are measured by gel permeation chromatography (GPC). Value.

[Crystal nucleating agent (B)]
In the present invention, the crystal nucleating agent (B) is a compound that can be a crystal nucleus of the lactic acid-based resin (A), and examples thereof include an inorganic compound (B-1) and an organic compound (B-2).

Examples of the inorganic crystal nucleating agent (B-1) include crystalline inorganic compounds containing 50% or more of SiO ₂ component, and examples thereof include silicate compounds such as talc, clay, kaolinite, kaolin clay, and the like. In particular, talc, clay and kaolin are preferable, and talc and clay are more preferable.

Specifically, talc TM-30 (manufactured by Fuji Talc Industrial Co., Ltd.), talc XE71 (manufactured by Fuji Talc Industrial Co., Ltd.), talc LMS350 (manufactured by Fuji Talc Industrial Co., Ltd.), kaolin JP-100 (manufactured by Tsuchiya Kaolin Co., Ltd.), NN kaolin Examples include clay (manufactured by Tsuchiya Kaolin Co., Ltd.), kaolinite ASP-170 (manufactured by Fuji Talc Kogyo Co., Ltd.), kaolin UW (manufactured by Engelhard Co., Ltd.), talc RF (manufactured by Fuji Talc Kogyo Co., Ltd.), and the like.
In particular, when talc is used, since the heat resistance and impact strength of the obtained molded product are increased, talc is preferably used. Further, talc having an average particle size of 0.1 to 6 μm, preferably 0.5 to 5 μm is desirable because it contributes significantly to the improvement of heat resistance and impact strength.

  As the organic crystal nucleating agent (B-2), an amide compound or polyamide compound having a melting point of 140 ° C. or higher, preferably 140 to 250 ° C., preferably 20 to 50, phosphate ester, CO, NH, A cyclic compound having a functional group selected from S and O in the molecule, or a mixture of a cyclic compound having CO in the molecule and a cyclic compound having a functional group selected from NH, S and O in the molecule; It is done.

  Examples of amide compounds having a melting point of 140 ° C. or higher and 20 or more carbon atoms include methylene bis stearic acid amide, ethylene bis lauric acid amide, ethylene bis capric acid amide, ethylene bis oleic acid amide, ethylene bis stearic acid amide, and ethylene bis erucic acid. Amides, ethylene bisbehenic acid amides, ethylene bisisostearic acid amides, ethylene bishydroxystearic acid amides, butylene bisstearic acid amides, hexamethylene bisoleic acid amides, hexamethylene bisstearic acid amides, hexamethylene bisstearic acid amides Aliphatic biscarboxylic amides such as ninamide, hexamethylenebishydroxystearic acid amide, m-xylylene bisstearic acid amide, m-xylylene bis-12-hydroxystearic acid amide And the like. These may be used alone or in a mixture of two or more.

  When these crystal nucleating agents (B) are mixed with the inorganic crystal nucleating agent (B-1) and the organic crystal nucleating agent (B-2), the dispersion of the inorganic crystal nucleating agent (B-1) is improved. This is particularly preferable because the conversion rate is improved. In particular, a preferable combination is a mixture of talc and alkylene bisamides such as ethylene bis stearamide, ethylene bis oleate amide, and ethylene laurate amide.

  The addition amount of the crystal nucleating agent (B) is 0.1 part by weight or more and 50 parts by weight or less, preferably 0.5 part by weight or more and 40 parts by weight or less with respect to 100 parts by weight of the lactic acid resin (A). More preferred is 1 to 30 parts by weight, still more preferred is 1 to 20 parts by weight, and most preferred is 1 to 10 parts by weight. Productivity, strength, heat resistance, workability, and economy are good within the range of this addition amount.

[Crystal Accelerator (C)]
In the present invention, the crystallization accelerator (C) means a compound having an effect of increasing the growth rate of the crystal of the lactic acid resin (A). For example, the aliphatic carboxylic acid amide (C-1), the aliphatic Carboxylic acid (C-2), aliphatic alcohol (C-3), and aliphatic carboxylic acid ester (C-4) are mentioned, and a compound having a melting point of 60 to 130 ° C. is preferable, and more preferably 70 to 130. ° C, more preferably 80 to 130 ° C, most preferably 80 to 130 ° C.

Within the above range, the heat resistance, storage stability, and durability of the obtained molded product are not impaired, the target crystallization rate of the present invention can be promoted, and the molded product according to the present invention can be obtained with high productivity. it can.
These may be one kind or a mixture of two or more kinds.

[Aliphatic carboxylic acid amide (C-1)]
The aliphatic carboxylic acid amide (C-1) used in the present invention is a compound usually having at least one bond called an amide bond in the molecule, having a melting point of 60 to 130 ° C. and having 10 to 10 carbon atoms. An aliphatic carboxylic acid amide having 50, preferably 15 to 40 carbon atoms, more preferably 15 to 30 carbon atoms, and most preferably 15 to 25 carbon atoms is preferable.
Examples of the aliphatic carboxylic amide in the method of the present invention include aliphatic monocarboxylic amides, aliphatic monocarboxylic bisamides, N-substituted aliphatic monocarboxylic amides, aliphatic biscarboxylic amides, and N-substituted fats. Group carboxylic acid bisamides and N-substituted ureas, and amides having a melting point of 60 to 130 ° C. shown above are preferably used. These may be one kind or a mixture of two or more kinds.

  Specific examples of the aliphatic carboxylic acid amide (C-1) include lauric acid amide, palmitic acid amide, stearic acid amide, oleic acid amide, erucic acid amide, behenic acid amide, hydroxystearic acid amide, It is available inexpensively and is preferably used.

[Aliphatic carboxylic acid (C-2)]
As aliphatic carboxylic acid (C-2) used by this invention, the compound shown by following General formula (1) is included, and especially aliphatic carboxylic acid whose melting | fusing point is 60 to 130 degreeC is preferable.

(R ¹ is a saturated or unsaturated or linear or branched hydrocarbon group having 10 to 40 carbon atoms). Specific examples include lauric acid, myristic acid, palmitic acid, oleic acid, stearin, isostearic acid, behenic acid, and montanic acid. These may be one kind or a mixture of two or more kinds.

[Fatty alcohol (C-3)]
As aliphatic alcohol (C-3) used by this invention, it is a compound shown by General formula (2), and especially the aliphatic alcohol whose melting | fusing point is 60 to 130 degreeC is preferable.

(R ² is a saturated, unsaturated, linear, branched or cyclic hydrocarbon group having 6 to 40 carbon atoms, and X represents a hydrogen atom or a hydroxyl group.)
Specific examples of the aliphatic alcohol (C-3) include aliphatic monoalcohols, aliphatic polyhydric alcohols, and cyclic alcohols (alicyclic alcohols).
These may be one kind or a mixture of two or more kinds.

[Aliphatic carboxylic acid ester (C-4)]
The aliphatic carboxylic acid ester (C-4) used in the present invention includes an aliphatic monocarboxylic acid ester represented by the following general formula (3), an ethylene glycol monoester represented by the general formula (4), and ethylene. Glycol diesters, glycerin monoesters represented by the general formula (5), glycerin diesters and glycerin triesters are included, and aliphatic carboxylic acid esters having a melting point of 60 ° C to 130 ° C are particularly preferable.

(R ³ and R ⁴ are each a saturated, unsaturated, or linear or branched hydrocarbon group having 10 to 40 carbon atoms, and X ₁ , X ₂ , X ₃ , X ₄ , and X ₅ are hydrogen atoms. Or a saturated or unsaturated or linear or branched acyl group having 2 to 40 carbon atoms, and n ₁ , n ₂ , n ₃ , n ₄ , and n ₅ may be the same or different, 0-4 is an integer of .X1, at least one X2 is a saturated or unsaturated carbon atoms 2 to 40, or a straight or branched acyl group, at least X _3, X _4, X ₅ One is a saturated or unsaturated, linear or branched acyl group having 1 to 40 carbon atoms)

  In the present invention, in terms of long-term storage stability of a molded product obtained from the resin composition (E), among these crystallization accelerators (C), there is a system in which an aliphatic carboxylic acid amide (C-1) is added. Since it is most stable, it can be preferably used. The crystallization accelerator (C) may be used alone or as a mixture of two or more thereof, and there is no limitation on the composition thereof.

[Addition amount of crystallization accelerator (C)]
The amount added to the lactic acid resin (A) is preferably 1 to 15 parts by weight, more preferably 1 to 13 parts by weight, still more preferably 100 parts by weight of the lactic acid resin (A). 3 to 10 parts by weight, most preferably 3 to 7 parts by weight. Productivity, strength, heat resistance, processability, and economic efficiency are good within the range of the addition amount. The lactic acid resin composition according to the present invention includes a lactic acid resin (A), a crystal nucleating agent (B), and A resin composition comprising a crystallization accelerator (C).

The lactic acid resin composition according to the present invention may contain a resin other than the lactic acid resin (A). As the resin other than the lactic acid resin (A), a thermoplastic resin is preferable.
Examples of the thermoplastic resin other than the lactic acid-based resin (A) include other hydroxycarboxylic acids, homopolymers and copolymers composed of polyhydric carboxylic acids and polyhydric alcohols (for example, polyglycolic acid, polycaproic acid, polybutylene succinate, poly Butylene succinate adipate, polyethylene adipate, polyethylene terephthalate adipate, polybutylene terephthalate adipate, etc.), polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, polyacetal, ABS, AS and the like.

  In particular, in applications where biodegradability is required, when polybutylene succinate or polyethylene terephthalate adipate is used, heat resistance is improved while maintaining biodegradability, which can be suitably used.

  On the other hand, when biodegradability is not required, a thermoplastic resin having a heat deformation temperature of 70 ° C. or higher, preferably 80 to 200 ° C., more preferably 80 to 175 ° C., particularly measured by a method according to ASTM D-648. Is preferably mixed. The thermoplastic resin in this range is preferable because the melted kneading with the lactic acid resin (A) can be performed well, so that the physical properties of the obtained mixture are stable, and higher heat resistance and impact resistance can be imparted. Can be used for

For example, polypropylene, polystyrene, polycarbonate, polyethylene terephthalate, polyethylene terephthalate, polyacetal, acrylonitrile-styrene copolymer (AS), acrylonitrile-butadiene-styrene copolymer (ABS), polymethylpentene, and the like are used.
In particular, polypropylene, polycarbonate, and ABS are highly effective in improving heat resistance, impact resistance, and durability, and are also preferable in terms of moldability and economy.
These thermoplastic resins can be used alone or in combination of two or more.

  The mixing amount is 5 to 75 parts by weight of the thermoplastic resin with respect to 25 to 95 parts by weight of the lactic acid resin (A), and preferably 10 to 10 parts of the thermoplastic resin with respect to 40 to 90 parts by weight of the lactic acid resin (A). 60 parts by weight is preferable, more preferably 10 to 50 parts by weight of thermoplastic resin with respect to 50 to 90 parts by weight of lactic acid resin (A), and most preferably 50 to 70 parts by weight of lactic acid resin (A). 30 to 50 parts by weight of the plastic resin is preferable.

[Other additives]
For the lactic acid-based resin composition of the present invention, a stabilizer (antioxidant, ultraviolet absorber, light stabilizer, etc.), flame retardant (bromine-based) depending on the application within the range not impairing the object of the present invention. Flame retardants, phosphorus flame retardants, melamine compounds, etc.), lubricants, mold release agents, antistatic agents, surface wetting improvers, colorants including dyes and pigments, and plasticizers, end-capping agents (epoxy compounds, oxazoline compounds, Carbodiimide compounds), modifiers such as impact modifiers, and the like can be added.
These additives can be used alone or in combination of two or more.

The impact modifier shown in the present invention means an additive capable of improving the impact resistance of the lactic acid resin composition. For example, usually a flexible polymer is added.
For example, in applications where biodegradability is required, a homopolymer or copolymer (for example, polycaproic acid, polyhydric acid) comprising hydroxycarboxylic acid, polycarboxylic acid and polyhydric alcohol having a lactic acid unit content of less than 50%. Butylene terephthalate adipate, copolymers of lactic acid and other components, etc., and in particular, polybutylene terephthalate adipate, Pramate PD-150 (trade name, manufactured by Dainippon Ink), Pramate PD-350 (trade name, large Nippon Ink Co., Ltd.) can be suitably used.

On the other hand, in the case of applications where biodegradability is not required, general-purpose impact resistance improvers and the like can be mentioned. For example, metabrene, styrene-ethylene-butadiene-rubber, in particular, metabrene has a high impact resistance improvement effect and is preferably used. I can do things.
These impact resistance improvers may be used alone or in a mixture of two or more.

The mixing amount of these impact resistance improvers is preferably 1 to 50 parts by weight, more preferably 3 to 30 parts by weight, and further preferably 5 to 25 parts by weight with respect to 100 parts by weight of the lactic acid resin (A). Parts are good, most preferably 5 to 20 parts by weight.
Within this range, it is possible to effectively improve the impact resistance of the lactic acid-based resin composition without impairing the effects of the present invention.

[Molding method] <Mixing, kneading, and kneading>
In the present invention, a method for producing a lactic acid-based resin composition can be carried out by a publicly known kneading technique such as a Henschel mixer, a ribbon blender, or the like. C) If necessary, other additives may be mixed in a solid state, or a method of kneading while melting the polymer using an extruder or the like may be employed.

For example,
(1) After powder-like or pellet-like lactic acid resin (A), crystal nucleating agent (B) and crystallization aid (C), and other additives as needed, are mixed together in a ribbon blender, etc. A method of extruding pellets while heating and melting the composition in a shaft extruder;
(2) When extruding and pelletizing a powdered or pelleted lactic acid resin (A), side feed the crystal nucleating agent (B) and the crystallization aid (C), and other additives as necessary. Or by adding and mixing into the cylinder of the extruder with a liquid injection pump;
(3) An organic crystal nucleating agent (B), a crystallization accelerator (C), and other additives as necessary are extruded in high concentration to produce pellets (master batch), and then the master batch. A method of processing a molded article by diluting with a lactic acid resin (A) in powder form or pellet form by dry blending or the like;
(4) A method in which the above methods are combined and mixed may be mentioned.

  In addition, when adding a crystal nucleating agent (B) and a crystallization aid (C), and other additives as a master batch as required, a master batch for each additive or a master of two or more additives. It may be added as a batch, and there is no limitation on the method. When added as a master batch, the mixing ratio with the lactic acid resin (A) is such that the weight ratio of the master batch / lactic acid resin (A) is 1/100 to 1/2, preferably 1/50 to 1 /. 3, more preferably 1/30 to 1/5, particularly preferably 1/30 to 1/10.

(Molding)
Below, the manufacturing method of the molded object which concerns on this invention is demonstrated. A method for producing a molded article having heat resistance which is an object of the present invention with high productivity will be described.

The present invention is a method for producing a molded article having high crystallinity and high heat resistance by crystallizing the lactic acid resin composition described above at the time of molding or after molding.
As molding methods, in general, injection molding, extrusion molding, blow molding (direct blow molding, injection blow molding, stretch blow molding), inflation molding, profile extrusion molding, injection blow molding, thermoforming (vacuum molding, vacuum pressure) Molding) and the like, and usual methods such as spinning, etc., but the resin composition shown in the present invention can be applied to any molding method and there is no limitation.

In the present invention, the molded body obtained from the lactic acid-based resin composition is preferably crystallized by some method (for example, heat treatment) at the time of molding or after molding.
As a specific example of crystallizing a lactic acid resin composition at the time of molding or after molding, for example, a method of filling a melt of the composition into a mold at the time of molding and crystallizing the mold as it is in the mold (hereinafter, And an in-mold crystallization method) and a method of once crystallizing an amorphous molded body of the composition (hereinafter referred to as a post-crystallization method).

Crystallization temperature condition and time The optimum temperature condition for crystallization of the lactic acid resin composition is preferably a temperature range of glass transition temperature (Tg) to melting point (Tm) in differential scanning calorimetry of the resin composition. A temperature range from the crystallization start temperature to the crystallization end temperature is more preferable, and a temperature near the top of the crystallization peak is more preferable.

  For example, when the lactic acid resin composition is a polylactic acid, the crystal nucleating agent (B) is talc, and the crystallization accelerator (C) is a stearamide, the Tg is about 60 ° C. and the Tm is about 165. C., the temperature of the crystallization peak is about 110.degree. C. Therefore, the set temperature of the mold is preferably 60 to 165.degree. C., the preferred temperature range is 90 to 120.degree. C., the more preferred temperature range is 95.degree. A preferred temperature range is 100 ° C to 110 ° C.

  Within this temperature range, the crystallization speed is remarkably increased and crystallization can be performed in a short time, and a molded product can be obtained stably and with good productivity.

  In addition, the time required for crystallization of the lactic acid resin composition at the time of molding or after molding varies slightly depending on the composition of the resin composition, the shape of the molded body, and the molding method. It is sufficient if the time is sufficient to crystallize substantially.

Below, the aspect of the shaping | molding method of the molded object which can provide crystallinity to a molded object based on this invention is demonstrated.
(1) Injection molding (in-mold crystallization method)
In injection molding (in-mold crystallization method), for example, a mixed composition in which a lactic acid resin composition is polylactic acid, a crystal nucleating agent (B) is talc, and a crystallization accelerator (C) is stearamide. In this case, the set temperature of the mold is preferably 60 to 165 ° C., preferably 90 to 120 ° C., more preferably 95 to 115 ° C., and further preferably 100 to 110 ° C. By holding and holding, the molded article having the crystallinity intended in the present invention can be molded in a short time.
The cooling time in the mold varies slightly depending on the thickness and shape of the molded product, but in the case of a 3 mm thick ASTM test piece, it is 5 to 40 seconds, preferably 10 to 35 seconds, more preferably 10 to 30 seconds.
In this range, crystallization proceeds to a high degree, and a molded product exhibiting high heat resistance can be obtained stably and with good productivity.

(2) Injection molding (post crystallization method)
In injection molding (post-crystallization method), for example, when using the lactic acid-based resin composition shown above, an amorphous molded body obtained by molding at a mold temperature of 20 ° C. is formed from Tg to Tm. Maintain in an atmosphere maintained at a temperature range, preferably 90 ° C. to 120 ° C., more preferably 95 ° C. to 115 ° C., and still more preferably 100 ° C. to 110 ° C., or contact with a solid material or a suitable heating medium As a result, it is possible to obtain in a short time an injection molded article having a high degree of crystallization and high heat resistance, which is the object of the present invention.

(3) Extrusion molding (crystallization method)
In extrusion molding (crystallization method), for example, the above-described lactic acid-based resin composition, a melted film or sheet obtained by a general T-die extrusion molding machine, and the temperature of a cooling roll are shown above. By maintaining the temperature within the above-described temperature range, the molded article having the crystallinity targeted by the present invention can be molded in a short time.
Specifically, by using a cooling roll maintained at a roll temperature of 60 to 165 ° C, preferably 90 ° C to 120 ° C, more preferably 95 ° C to 115 ° C, still more preferably 100 ° C to 110 ° C, A film or sheet having a high degree of crystallinity targeted by the invention can be formed in a short time.
The contact time with the cooling roll varies slightly depending on the thickness and shape of the film and sheet, but in the case of a 3 mm thick film and sheet, it is 5 to 40 seconds, preferably 10 to 35 seconds, more preferably 10 to 30 seconds. is there.
In this range, crystallization is advanced to a high degree, and a film and seam exhibiting high heat resistance can be obtained stably and with high productivity.

(4) Extrusion molding (post-crystallization method)
In extrusion molding (post-crystallization method), for example, an amorphous film / sheet obtained by molding the lactic acid resin composition shown above with a general T-die extruder is used as described above. High crystallization targeted by the present invention can be maintained in an oven maintained in the indicated temperature range, continuously passed through a metal roll or a suitable heating medium, or heat treated batchwise. A film or sheet having a degree can be obtained in a short time.
The holding time or contact time at this time is a film. Although it varies slightly depending on the thickness and shape of the sheet, it is 5 to 40 seconds, preferably 10 to 35 seconds, more preferably 10 to 30 seconds in the case of a 3 mm thick film or sheet. In this range, crystallization is advanced to a high degree, and a film and seam exhibiting high heat resistance can be obtained stably and with high productivity.

(5) Thermoforming (post-crystallization method)
In this molding method, an amorphous film sheet obtained by the same method as in the above (4) is used, and a hot plate heating / compressing air used in a vacuum (compressed air) molding machine or OPS usually used in PS or PET. The film sheet is once preheated by molding or the like, and then formed into a mold held in the temperature range shown above.
A suitable temperature range in the case of this molding method is the same as the aforementioned range.
The time for contacting with the mold is relatively short, since crystallization proceeds in advance during preheating, and is 1 to 20 seconds, preferably 1 to 10 seconds, more preferably 1 to 5 seconds. Within this range, crystallization proceeds to a high degree, and a thermoformed product exhibiting high heat resistance can be obtained stably and with good productivity.

  Here, the pressure air is a high temperature [for example, a temperature of Tg (60 ° C.) or more to Tm (165 ° C.) or less, more preferably 70 to 145 ° C., more preferably 80 to 135 ° C., and even more preferably. When the temperature of 90 ° C. to 125 ° C., most preferably 100 ° C. to 115 ° C. is used, the time required for crystallization of the molded product can be shortened.

(6) Injection stretch blow molding (post-crystallization method)
In this blow molding (post-crystallization method), for example, a pellet of a lactic acid resin composition is melted with a general injection molding machine and filled into a mold to form an amorphous preform (Parison). After the obtained parison is preheated in an oven (heating furnace), it is placed in a mold maintained in the temperature range shown above, and is sent by blowing out pressure air, The blow bottle having the crystallinity intended in the present invention can be formed in a short time.

Also in this molding method, a suitable temperature range is the same as the above-described range.
Further, the time for contacting the mold is the same as in the case of the thermoforming, and since crystallization proceeds in advance during preheating, the time is relatively short, 1 to 20 seconds, preferably 1 to 10 seconds, more preferably 1 ~ 5 seconds. Crystallization proceeds to a high degree within this range, and a blow bottle exhibiting high heat resistance can be obtained stably and with good productivity.

  Here, as in the case of the above thermoforming, the pressure air is a high temperature [for example, a temperature of Tg (60 ° C.) or higher to Tm (165 ° C.) or lower, more preferably a temperature of 70 to 145 ° C., more preferably 80 ° C. to If the temperature is 135 ° C., more preferably 90 ° C. to 125 ° C., most preferably 100 ° C. to 115 ° C., the time required for crystallization can be shortened.

(Physical properties of lactic acid resin composition)
The molded body obtained from the lactic acid-based resin composition of the present invention exhibits physical properties that are hard and have high heat resistance by the above molding methods. For example, the physical properties of a test piece obtained by injection molding have a flexural modulus of 2000 MPa to 5000 MPa in a method according to ASTM D790.

  Moreover, the heat deformation temperature (0.45 MPa load) measured on the conditions based on ASTM D648 shows 70-150 degreeC, Preferably it shows 80-140 degreeC, More preferably, it shows 80-130 degreeC, More preferably Shows 90-130 degreeC, Most preferably, it shows 100-130 degreeC.

(Use)
Molded articles comprising the lactic acid resin composition of the present invention are injection-molded articles, films, bags, tubes, sheets, cups, bottles, trays, fibers, foams, laminates, tapes obtained by known and publicly-known molding methods. -Including yarn, non-woven fabric molding (spunbond method, meltblown method), yarn, etc., there are no restrictions on the shape, size, thickness, design, etc.

  Specifically, the molded article of the present invention includes food packaging bags, containers and trays for food such as tableware, forks and spoons, bottles for dairy products, soft drinks and alcoholic beverages, wrap films, cosmetic containers, Garbage bags, umbrellas, tents, tarpaulins, (adhesive) tapes, air mats, bleach containers, liquid detergent bottles, containers and packaging materials for medical instruments and materials, pharmaceutical containers and packaging materials, Suspension, fishnet, containers and packaging materials and capsules for agricultural products, containers and packaging materials and capsules for fertilizers, containers and packaging materials and capsules for seedlings, agricultural and horticultural films, films for product packaging, films for overhead projectors, It can be used for a heat ray reflective film, a liquid crystal display film and the like. In addition, the film or sheet obtained by the method of the present invention is made into a multilayered structure by laminating or bonding with sheets of other materials such as paper and other polymers, and adhesive or heat fusion. You can also. In particular, when an amorphous amorphous polyester film having excellent transparency such as a polylactic acid or a copolymer having a polylactic acid block and a polybutylene succinate block is thermally laminated on, for example, paper There is a problem that it becomes crystallized and opaque due to heat during lamination. Therefore, in applications where transparency is required, heat treatment conditions during thermal lamination are preferably limited, or lamination methods using adhesives are preferably used, and furthermore, in applications where transparency and heat resistance are required. The resin composition could not be used. However, when those resin compositions (E) containing the transparent nucleating agent of the present invention are used, for example, an amorphous film is directly heat-laminated to paper or the like, bonded to paper or the like, and the composition of Crystallization may be performed simultaneously. Further, the laminated body once thermally laminated may be further heat-treated to be crystallized. Under any condition, it is possible to obtain a laminate that maintains its transparency and further imparts heat resistance.

  The resin composition of this invention can be shape | molded with the various shaping | molding processing method mentioned above, and can be used suitably for various uses, without being specifically limited. In addition, these resin compositions are excellent in heat resistance and impact resistance, and also have good moldability, so electric / electronic parts, home appliance parts, building civil engineering members, automotive interior / exterior parts, agricultural materials, packaging materials, clothing, It can be used in various applications such as daily necessities, various films, breathable films and sheets, foams suitable for general industrial and recreational use, yarns and textiles, medical or sanitary products, and the like.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.
In the present invention, various physical properties were measured and evaluated by the following methods.
The evaluation conditions for the physical properties of the molded articles produced using the lactic acid resin compositions obtained in Production Examples 1 to 7 are as follows.

[Glass transition temperature (Tg), melting point (Tm), crystallization peak temperature (Tc), crystallinity]
Using a differential scanning calorimeter (manufactured by Shimadzu Corporation, DSC-50), the point at which the lactic acid resin composition changes to a rubbery shape when heated at 10 ° C./min is the glass transition point (Tg), The crystallization temperature (Tc) and the crystallization energy (ΔHc) were measured at the top of the crystallization peak, and the melting point (Tm) and the melting energy (ΔHm) were measured at the top of the crystallization melting peak. The temperature at which crystallization starts was defined as the crystallization start temperature (Tcs), and the temperature at which the crystallization was terminated was defined as the crystallization end temperature (Tce). The degree of crystallinity was calculated by the following equation using the values of ΔHm and ΔHc.
Crystallinity = (ΔHm−ΔHc) / 93 × 100

[Impact resistance (Izod impact strength)]
It measured on the conditions based on ASTM D-256 using the ASTM test piece of thickness 3.2mm of a lactic acid-type resin composition. The notch is a molded notch.

[Tensile strength, tensile elongation]
It measured on the conditions based on ASTM D-638 using the ASTM test piece of thickness 3.2mm of a lactic acid-type resin composition.

[Bending strength, flexural modulus]
It measured on the conditions based on ASTM D-790 using the ASTM test piece of thickness 3.2mm of a lactic acid-type resin composition.

[Heating deformation temperature]
Low load (0.45 MPa load) (low load HDT), high load (1.82 MPa load) by a method based on ASTM D-648 using a 3.2 mm thick ASTM test piece of lactic acid resin composition It was measured under two conditions (high load HDT).

[Evaluation of formability]
Evaluation was performed by observing the state of the obtained test piece when injection molding was performed at a cylinder set temperature of 190 to 200 ° C. using an ASTM test piece mold having a thickness of 3.2 mm set at a temperature of 100 ° C.
○ ・ ・ ・ Test specimen does not deform when removed × ・ ・ ・ Test specimen deforms when removed

[Example 1.1] Injection molding As lactic acid-based resin (A), LACEA H-100 (polylactic acid) (trade name: sold by Mitsui Chemicals, Mw = 14,000, D-body weight = 1.6%) 100 Part, talc 5 parts by weight (talc XE71, manufactured by Fuji Talc) as crystal nucleating agent (B), and 5 parts by weight stearamide as crystallization accelerator (C) are mixed with a Henschel mixer and extruded. Pelletization was performed at a machine cylinder set temperature of 170 to 210 ° C. The pellet of the obtained resin composition uses a mold for an ASTM test piece having a thickness of 3.2 mm, in which the Tg is 59 ° C., the crystallization peak temperature is 110 ° C., and the melting point is 168 ° C. The temperature is set to 100 ° C. The injection molding was performed with JSW-75 manufactured by Nippon Steel Works at a cylinder set temperature of 190 to 200 ° C.
When the injection time was 10 sec and the cooling time in the mold was 20 seconds, the moldability (presence or absence of deformation during removal) was good.

  The crystallinity of the obtained specimen is 45%, the heat deformation temperature under low load (low load HTD) is 110 ° C., the heat deformation temperature under high load (high load HTD) is 61 ° C., and the Izod impact strength is It was 45 J / m, the tensile strength was 59 MPa, the bending strength was 85 MPa, and the flexural modulus was 4800 MPa. The results are shown in Table 1.

[Examples 1.2 to 1.9] Injection type lactic acid-based resin (A), crystal nucleating agent (B), crystallization accelerator (C), other than changing the type and amount of other additives, The same method as in Example 1.1 was performed. The results are shown in Table 1.

[Comparative Example 1.1] Injection Molding As Lactic Acid Resin (A) LACEA H-100 (Polylactic Acid) (trade name: sold by Mitsui Chemicals, Mw = 14,000, D-body amount = 1.6%) 100 The same procedure as in Example 1 was carried out except that 5 parts by weight of the inorganic crystal nucleating agent talc was used as the weight part and the crystal nucleating agent (B).
The injection moldability of the obtained pellet was poor, such as deformation when taking out a test piece from the mold, and physical properties such as heat deformation temperature could not be measured. The crystallinity was 14%.

[Comparative Examples 1.2 to 1.9] Injection Molding Other than changing the type and amount of addition of lactic acid resin (A), crystal nucleating agent (B), crystallization accelerator (C), other additives, The same method as in Comparative Example 1 was performed. The results are shown in Table 2. In addition, when the test piece was taken out from the mold, the physical properties could not be measured when the deformation was large.

The lactic acid resin (A), crystal nucleating agent (B), crystallization accelerator (C), other resin, and modifier described in the table are the compounds shown below.
H-100: Polylactic acid (trade name: LACEA H-100, Mw = 14,000, D-body weight = 1.6%, sold by Mitsui Chemicals))
STA: Stearic acid (melting point: 60 ° C.)
ELA: erucic acid amide (melting point: 80 ° C.)
STA: stearamide (melting point 100 ° C.)
EBS: Ethylene bis stearamide (melting point: 140 ° C.)
PC: Polycarbonate (Panlite L-1225L; trade name, manufactured by Teijin Chemicals Ltd.)
(Low load HDT: 120 ° C)
PP: Polypropylene
(Prime Polypro J108M; trade name made by Prime Polymer)
(Low load HDT: 139 ° C)
ABS: Copolymer of acrylonitrile-butadiene-styrene
(Santac UT-61; product name manufactured by Nippon A & L Co., Ltd.)
(Low load HDT: 90 ° C)
ATBC: Acetyltributylcitric acid (freezing point: −80 ° C.)
METABLEN: Product name (Mitsubishi Rayon Co., Ltd.)
Talc: (Talc XE71, manufactured by Fuji Talc) Melting point: 500 ° C or higher

[Example 2.1] Extrusion molding LACEA H-100 (trade name: sold by Mitsui Chemicals) as lactic acid resin (A) 100 parts, talc of inorganic crystal nucleating agent as crystal nucleating agent (B) 5 parts by weight, crystals 5 parts by weight of stearamide as a crystallization accelerator (C) was mixed with a Henschel mixer, and then pelletized under conditions of an extruder cylinder set temperature of 170 to 210 ° C. The resulting resin composition pellets had a Tg of 59 ° C., a crystallization peak temperature of 110 ° C., and a melting point of 168 ° C.
Using the pellets of this resin composition, a T-die 50 mmΦ extruder (manufactured by Frontier, die width 400 mm) was melted under conditions of a cylinder set temperature of 180 to 200 ° C, and the sheet was extruded at a die temperature of 185 ° C. The roll temperature was set to 90 ° C., and the roll diameter and the rotation speed were adjusted with respect to the extrusion amount so that the time for which the sheet contacted the roll was 20 seconds. The crystallinity of the obtained sheet (thickness 0.25 mm) was 46%.

[Comparative Example 2.1] Extrusion molding As lactic acid-based resin (A), LACEA H-100 (trade name: sold by Mitsui Chemicals) 100 parts, as crystal nucleating agent (B), 5 parts by weight of inorganic crystal nucleating agent talc, Otherwise, the same method as in Example 2.1 was performed, but the sheet was not peeled off from the roll, and a good sheet could not be obtained. The crystallinity of this sheet was 18%.

[Example 2.2] Extrusion molding (post-crystallization)
LACEA H-100 (trade name: sold by Mitsui Chemicals) as lactic acid resin (A) 100 parts, talc of inorganic crystal nucleating agent 5 parts by weight as crystal nucleating agent (B), stearic acid as crystallization accelerator (C) After mixing 5 parts by weight of the amide with a Henschel mixer, the mixture was pelletized under conditions of an extruder cylinder set temperature of 170 to 210 ° C. The resulting resin composition pellets had a Tg of 59 ° C., a crystallization peak temperature of 110 ° C., and a melting point of 168 ° C.
Using the pellets of this resin composition, a T-die 50 mmΦ extruder (manufactured by Frontier, die width 400 mm) was melted under conditions of a cylinder set temperature of 180 to 200 ° C, and the sheet was extruded at a die temperature of 185 ° C. The roll temperature was set to 35 ° C., and an amorphous sheet having a thickness of 250 μm was obtained.
The sheet was passed through a hot air dryer (temperature 100 ° C., residence time 25 sec) continuously and heat-treated. The crystallinity of the obtained sheet was 43%.

[Comparative Example 2.2] Extrusion molding (post-crystallization)
Example 2.2 except that LACEA H-100 (trade name: sold by Mitsui Chemicals) as lactic acid resin (A) and 5 parts by weight of talc of inorganic crystal nucleating agent as crystal nucleating agent (B) were used. It went by the method.
The resulting amorphous sheet was passed through a hot-air dryer (temperature 100 ° C., residence time 25 sec) and heat-treated, but the crystallinity of the sheet was 12% and it was not sufficiently crystallized. Could not get the sheet.

[Example 3.1] Thermoforming The amorphous sheet having a thickness of 250 µm obtained in Example 2.2 was preheated at a heater temperature of 350 ° C for 5 seconds using a vacuum / pressure forming machine, and then the mold temperature was 100 ° C and the pressure was reduced. The mold was formed into a mold with a pressure of 4 kgf / cm ² and a degree of vacuum of 5 mmHg, and molded with a residence time of 5 sec in the mold. As the shape of the mold at this time, a mold tray having a length × width × height of 12 cm × 12 cm × 4 cm and a drawing ratio of 0.25 was used.
The resulting molded product tray did not deform even when left in an oven at 100 ° C. for 1 hour.

[Comparative Example 3.1] Thermoforming Using a sheet having a thickness of 250 μm obtained in Comparative Example 2.2, vacuum-pressure forming was performed in the same manner as in Example 3.1. Could not get. The crystallinity of the obtained tray was 11%, and the deformation was further increased when placed in an oven at 100 ° C.

[Comparative Example 3.2] Thermoforming Except that the mold temperature was set to 35 ° C., the same method as in Comparative Example 3.1 was used to obtain a tray with good saddle shape.
The crystallinity of this tray was 20%. The tray of the obtained molded product was deformed into a flat plate shape when left in an oven at 100 ° C. for 1 hour.

[Example 4.1 [Blow molding]]
LACEA H-100 (trade name: sold by Mitsui Chemicals) as lactic acid resin (A) 100 parts, talc of inorganic crystal nucleating agent 5 parts by weight as crystal nucleating agent (B), stearic acid as crystallization accelerator (C) After mixing 5 parts by weight of the amide with a Henschel mixer, the mixture was pelletized under conditions of an extruder cylinder set temperature of 170 to 210 ° C. The pellets of the resin composition thus obtained had an Tg of 59 ° C., a crystallization peak temperature of 110 ° C., and a melting point of 168 ° C. This pellet was injection blow molding machine (manufactured by Nissei ASB Machine, ASB-50), cylinder setting Melting was performed under conditions of a temperature of 180 to 200 ° C., filling in a mold (A) with a set temperature of 20 ° C., and a cooling time was 30 seconds, and a 2.0 mm thick preform (bottomed parison) was obtained. The obtained parison is heated in a heating furnace to a parison temperature of 110 ° C. and placed in a mold maintained at 100 ° C., and the vertical magnification is doubled under the condition of pressure air pressure of 4 kgf / cm ^2. The horizontal magnification was doubled, and a container with 500 ml of contents was obtained with a mold contact time of 5 sec.
The degree of crystallinity of the obtained container (thickness 0.5 mm) was 48%, and it did not deform even when the container was left in an oven at 100 ° C. for 1 hour.

[Comparative Example 4.1 [Blow Molding]]
The same as in Example 4.1 except that LACEA H-100 (trade name: sold by Mitsui Chemicals) as 100 parts of lactic acid resin (A) and 5 parts by weight of talc of inorganic crystal nucleating agent as nucleating agent (B) were used. However, the container was deformed when the container was taken out, and a good container could not be obtained.

[Comparative Example 4.2 [Blow Molding]]
Except that the mold temperature was set to 35 ° C., the same method as in Comparative Example 4.1 was used to obtain a tray with good saddle shape. The crystallinity of this tray was 24%. The tray of the obtained molded product was greatly deformed when left in an oven at 100 ° C. for 1 hour.

Claims (10)

It comprises 0.1 to 50 parts by weight of a crystal nucleating agent (B) and 1 to 15 parts by weight of a crystallization accelerator (C) having a melting point of 60 to 130 ° C. with respect to 100 parts by weight of a lactic acid resin (A). Lactic acid resin composition. The lactic acid resin composition according to claim 1, wherein the crystallization accelerator (C) is one or a mixture of two or more selected from amide compounds, alcohol compounds, carboxylic acid compounds, and ester compounds. The lactic acid resin composition according to claim 1 or ₂ , wherein the crystal nucleating agent (B) is a crystalline inorganic compound containing 50% or more of a SiO2 component. The lactic acid resin composition according to claims 1 to 3, wherein the crystal nucleating agent (B) is selected from the group consisting of talc, clay, kaolinite, kaolin clay and silicic acid compound. A thermoplastic resin (D) having a heat deformation temperature (0.45 MPa load) measured by a method according to ASTM D-648 of 100 parts by weight of the lactic acid resin composition (A) according to claims 1 to 4 ) A lactic acid resin composition comprising 1 to 50 parts by weight. 6. The lactic acid series according to claim 5, wherein the thermoplastic resin fat (D) is at least one or a mixture of two or more from the group consisting of polypropylene, polycarbonate, acrylonitrile-styrene copolymer, and acrylonitrile-butadiene-styrene copolymer. Resin composition. A molding characterized in that the lactic acid resin composition according to claim 1 is crystallized in a temperature range of a glass transition temperature (Tg) to a melting point (Tm) of the lactic acid resin composition at the time of molding or after molding. Body manufacturing method. The lactic acid resin composition according to any one of claims 1 to 6 is inserted into a mold held at a crystallization start temperature to a crystallization end temperature of the lactic acid resin composition and crystallized as it is. A method for producing a molded article. The lactic acid resin composition according to any one of claims 1 to 6 is once cooled and solidified to obtain an amorphous molded body, and then the resin composition is (glass transition temperature (Tg) +10) ° C. to (melting point (Tm) -20. ) A method for producing a molded article characterized by heat treatment at a temperature of ° C. and crystallization. The molded object obtained by the manufacturing method of Claims 7-9.