JP5282436B2 - Polylactic acid film and resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polylactic acid-based film having excellent heat resistance, impact resistance and transparency, and to provide a resin composition. <P>SOLUTION: The polylactic acid-based film and the resin composition have crystallinity regulated so that the film and the resin composition may have an &alpha; crystal of the polylactic acid, and a crystal (&alpha;' crystal) of the polylactic acid, having a peak of 2&theta; within the range of (a-0.2)&deg;&le;2&theta;&le;(a-0.01)&deg; [wherein (a) is the peak of the 2&theta; of the &alpha; crystal by X-ray diffraction], the ratio of crystal intensities of the &alpha; crystal to the &alpha;' crystal is from 99/1 to 1/99, and the crystallinity is 3-60%. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a polylactic acid film having heat resistance, impact resistance, transparency, and moldability, and a resin composition.

  In recent years, with increasing environmental awareness, attention has been focused on soil pollution problems caused by the disposal of plastic products and global warming problems caused by increased carbon dioxide caused by incineration. Various biodegradable resins have been researched and developed as countermeasures against the former, and resins made from plant-derived materials that do not give a new carbon dioxide load to the atmosphere even when incinerated as countermeasures against the latter. Yes. For shape retainers used for display and packaging of various products, and containers such as food trays and beverage cups, products using various biodegradable resins and resins made from plant-derived materials have been developed. Yes. In particular, polylactic acid, which is an aliphatic polyester, has attracted the most attention as a promising material because it is biodegradable and has a high glass transition point of about 60 ° C. as a plant-derived plastic and is transparent.

  However, polylactic acid has a glass transition point of about 20 ° C. lower than that of conventional petroleum-derived raw materials such as polyethylene terephthalate. For this reason, when it uses for each present use, there exists a problem that heat resistance is insufficient.

  As a means for solving this problem, a technique for crystallizing polylactic acid and improving heat resistance has been proposed (see, for example, Patent Documents 1 to 5).

  For example, Patent Document 1 describes a technique for increasing the crystallinity by heat-treating a polylactic acid composition containing a transparent nucleating agent during or after molding. In this technique, heat treatment is performed by crystallizing by molding die heat treatment during molding or heat treatment after molding. For this reason, there exists a problem that the heat resistance of film itself is insufficient.

  Patent Document 2 describes a technique for imparting heat mold releasability at the time of molding by heat-treating or stretching-oriented the film before molding. However, this technique has a problem that the transparency of the film and the molded product is greatly insufficient.

  Patent Document 3 describes a technique for imparting thermoformability to a stretched film by mixing crystalline polylactic acid and amorphous polylactic acid. However, this technique contains 50% or more of amorphous polylactic acid. For this reason, there exists a problem that sufficient heat resistance cannot be provided.

  Patent Document 4 proposes a polylactic acid-based film having a two-fold, three-layer film structure having a polylactic acid and a lactic acid-based polyester in the inner layer and a polylactic acid containing a transparent nucleating agent in the outer layer and having a high bending strength. However, the technique disclosed herein has a problem that transparency is deteriorated by heat treatment during molding.

Patent Document 5 proposes a technique for achieving both moldability and heat resistance by thermally crystallizing a laminated film composed of two layers having a difference in D-form content of the polylactic acid resin, that is, crystallinity. However, this technique has a problem that transparency is greatly insufficient.
JP-A-9-278991 JP 2003-245971 A JP 2004-204128 A JP 2005-119062 A JP 2005-125765 A

  Accordingly, an object of the present invention is to solve the above-described problems and provide a polylactic acid film and a resin composition excellent in heat resistance, impact resistance, and transparency.

  In order to solve the above-mentioned problems, the present inventors suppress the excessive growth of either crystal by causing polylactic acid α crystal and a crystal different from α crystal to exist in the composition or film. The present inventors have found that a polylactic acid film and a resin composition excellent in heat resistance, impact resistance and transparency can be obtained by finely arranging fine crystals, and completed the present invention. That is, the present invention is as follows.

  The polylactic acid-based film and the polylactic acid-based resin composition of the present invention are a polylactic acid-based film having a crystallinity and a resin composition, and the polylactic acid-based film or the resin composition is an α of polylactic acid. A polylactic acid having a peak in the range of (a−0.2) ° ≦ 2θ ≦ (a−0.01) ° when the 2θ peak of the α crystal is defined as a ° by X-ray diffraction The crystal ratio obtained from the intensity ratio of the α crystal and the α ′ crystal is 99/1 to 1/99, and the crystallinity is 3 to 60%.

  The polylactic acid film and the resin composition may contain a crystal nucleating agent.

  The crystal nucleating agent is preferably at least one selected from the group consisting of aliphatic carboxylic acid amides and N-substituted ureas.

  It is preferable that the polylactic acid film and the resin composition contain a compound having hydrogen bonding property with the crystal nucleating agent together with the crystal nucleating agent. The compound having hydrogen bonding property with the crystal nucleating agent may be at least one selected from the group consisting of aliphatic alcohols, sorbitol compounds, amino acids, and polypeptides.

  The polylactic acid film may have a haze of 20% or less.

The polylactic acid film and the resin composition of the present invention have good heat resistance, impact resistance, and transparency. The resin composition in the present invention includes a film and a molded body (→ In the present invention, the crystal ratio and crystallinity in the final use state are important, but this application seems to be pointed out. However, it was difficult to specify the degree of crystallinity before molding of resin compositions other than film (such as injection-molded bodies). Therefore, in this application, we would like to change the shape of the resin composition to include film, molded product, etc. Please confirm that the description is tailored to the change.
), Shape retainers such as various blister packs, food trays that require heat resistance and transparency, containers such as beverage cups, display bottles and cans for beverage vending machines that require heat resistance It can be preferably used for packaging materials, industrial materials such as surface materials and laminates, and electronic parts conveying applications such as carrier tape.

Hereinafter, embodiments of the present invention will be described in detail.
[Polylactic acid]
The polylactic acid used in the present invention is a polymer mainly composed of L-lactic acid and / or D-lactic acid unit. The poly-L-lactic acid referred to in the present invention is preferably such that the content ratio of L-lactic acid units in the total lactic acid component of the polylactic acid polymer is more than 50 mol% and not more than 100 mol%. The content of the L-lactic acid unit in the total lactic acid component of the coalescence is more preferably from 80 mol% to 100 mol%, more preferably from 95 mol% to 100 mol%, and from 98 mol% to 100 mol%. Is even more preferred. On the other hand, the poly D-lactic acid referred to in the present invention preferably has a D-lactic acid unit content of more than 50 mol% and not more than 100 mol% in the total lactic acid component of the polylactic acid polymer. The content ratio of the D-lactic acid unit in the total lactic acid component of the lactic acid polymer is more preferably from 80 mol% to 100 mol%, more preferably from 95 mol% to 100 mol%, and from 98 mol% to 100 mol%. Even more preferably. In poly L-lactic acid, the crystallinity of the resin itself varies depending on the content ratio of the D-lactic acid unit. That is, if the content ratio of the D-lactic acid unit in the poly-L-lactic acid increases, the crystallinity of the poly-L-lactic acid becomes lower and becomes closer to an amorphous state, and conversely, the content ratio of the D-lactic acid unit in the poly-L-lactic acid. As the amount decreases, the crystallinity of poly-L-lactic acid increases. Similarly, in poly D-lactic acid, the crystallinity of the resin itself changes depending on the content ratio of the L-lactic acid unit. That is, if the content ratio of the L-lactic acid unit in the poly-D-lactic acid increases, the crystallinity of the poly-D-lactic acid becomes low and approaches an amorphous state. Conversely, the content ratio of the L-lactic acid unit in the poly-D-lactic acid. As the amount decreases, the crystallinity of poly-D-lactic acid increases.

  In addition, the polylactic acid used in the present invention is preferably composed of a mixture of poly L-lactic acid and poly D-lactic acid from the viewpoint of improving the heat resistance using a stereocomplex crystal having a high crystal melting point.

  The polylactic acid used in the present invention may contain a monomer unit other than lactic acid. Other monomers include ethylene glycol, propylene glycol, butanediol, heptanediol, hexanediol, octanediol, nonanediol, decanediol, 1,4-cyclohexanedimethanol, neopentyl glycol, glycerin, pentaerythritol, bisphenol. A, glycol compounds such as polyethylene glycol, polypropylene glycol and polytetramethylene glycol, oxalic acid, adipic acid, sebacic acid, azelaic acid, dodecanedioic acid, malonic acid, glutaric acid, cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, phthalate Acid, naphthalenedicarboxylic acid, bis (p-carboxyphenyl) methane, anthracene dicarboxylic acid, 4,4′-diphenyl ether dicarboxylic acid, -Dicarboxylic acids such as sodium sulfoisophthalic acid, 5-tetrabutylphosphonium isophthalic acid, glycolic acid, hydroxypropionic acid, hydroxybutyric acid, hydroxyvaleric acid, hydroxycaproic acid, hydroxybenzoic acid and other hydroxycarboxylic acids, caprolactone, valerolactone, Examples include lactones such as propiolactone, undecalactone, and 1,5-oxepan-2-one. The copolymerization amount of the other monomer units is preferably 0 to 30 mol%, and more preferably 0 to 10 mol%, based on the entire monomer units of the polylactic acid resin.

  The weight average molecular weight of the polylactic acid used in the present invention is preferably 50,000 to 500,000, more preferably 100,000 to 250,000, in order to satisfy appropriate molding processability and practical mechanical properties. . In addition, a weight average molecular weight here means the molecular weight which measured with the chloroform solvent by the gel permeation chromatography (GPC), and was calculated by the polymethylmethacrylate conversion method.

  The polylactic acid resin composition and film of the present invention may contain a resin other than polylactic acid. The content is preferably 0 to 80% by mass, more preferably 0 to 60% by mass, and still more preferably 0 to 40% by mass with respect to the total mass.

  Examples of resins other than polylactic acid include thermoplastic resins such as polyacetal, polyethylene, polypropylene, polyamide, poly (meth) acrylate, polyphenylene sulfide, polyether ether ketone, polyester, polysulfone, polyphenylene oxide, polyimide, and polyetherimide, Thermosetting resins such as phenol resin, melamine resin, polyester resin, silicone resin, epoxy resin, ethylene / glycidyl methacrylate copolymer, polyester elastomer, polyamide elastomer, ethylene / propylene terpolymer, ethylene / butene-1 copolymer, etc. And a soft thermoplastic resin.

  Among these, poly (meth) acrylate is preferred because it has good compatibility with polylactic acid, improves the glass transition temperature of the resin composition after mixing, and improves high-temperature rigidity. The poly (meth) acrylate has at least one monomer selected from acrylate and methacrylate as a structural unit, and two or more monomers may be copolymerized and used. Specifically, polymethyl methacrylate or the like can be used. In particular, polyester resins are preferable from the viewpoint of imparting impact resistance. Specifically, polybutylene adipate / terephthalate, polybutylene succinate / adipate, and the like can be used.

The polylactic acid-based film and the resin composition of the present invention have a carboxyl group terminal concentration of the polylactic acid-based resin of 0.1 to 30 equivalents / 10 ³ from the viewpoint of suppressing strength reduction due to decomposition and improving heat resistance. It is preferably kg, more preferably 0.5 to 20 equivalents / 10 ³ kg, and particularly preferably 1 to 10 equivalents / 10 ³ kg. When the carboxyl group terminal concentration of the polylactic acid-based resin is 30 equivalents / 10 ³ kg or less, the polylactic acid-based film and the resin composition are used under conditions of high temperature and high humidity or contact with hot water. It is preferable in that it can prevent a decrease in strength due to hydrolysis. That is, when used for applications such as containers, it is possible to prevent problems such as the containers becoming brittle and easily broken.

Examples of the method for setting the carboxyl group terminal concentration to 30 equivalents / 10 ³ kg or less include, for example, a method of controlling by a catalyst or thermal history during synthesis of a polylactic acid resin, a method of blocking a carboxyl group terminal using a reactive compound, etc. Is mentioned. Examples of reactive compounds include condensation reactive compounds such as aliphatic alcohols and amide compounds, and addition reactive compounds such as carbodiimide compounds, epoxy compounds, and oxazoline compounds, but extra byproducts are generated during the reaction. Addition reaction type compounds are preferred because of their difficulty.

  In the polylactic acid-based film and the resin composition of the present invention, the amount of lactic acid oligomer components contained in the film and the resin composition is preferably 0% by mass or more and 0.3% by mass or less. More preferably, they are 0 mass% or more and 0.25 mass% or less, More preferably, they are 0 mass% or more and 0.2 mass% or less. When the amount of the lactic acid oligomer component contained in the film and the resin composition is 0.3% by mass or less, the lactic acid oligomer component remaining in the film and the resin composition is precipitated as a powder or liquid and handled. It is preferable at the point which can prevent deterioration of a property and transparency, and the point which can advance the hydrolysis of polylactic acid resin and can also prevent the deterioration of the aging resistance of a film and a resin composition. The term “lactic acid oligomer component” as used herein refers to a cyclic dimer (lactide) of lactic acid, which is the most quantitatively representative of lactic acid, linear oligomers of lactic acid, and cyclic oligomers present in the composition and film. LL-lactide and DD-lactide, DL (meso) -lactide.

(Crystal nucleating agent)
The polylactic acid film and the resin composition of the present invention preferably contain a crystal nucleating agent. The role of the crystal nucleating agent is to suppress excessive growth of the polylactic acid-based film and the polylactic acid crystal forming the resin composition, to refine the crystal, and to increase the crystallization speed. Crystal nucleating agents having such a role include aliphatic carboxylic acid amides, N-substituted ureas, aliphatic carboxylates, aliphatic alcohols, aliphatic carboxylic acid esters, aliphatic / aromatic carboxylic acid hydrazides, and sorbitols. Compounds, melamine compounds, phenylphosphonic acid metal salts, amino acids, polypeptides and the like can be used. Among these, compounds selected from aliphatic carboxylic acid amides, sorbitol compounds, amino acids, and polypeptides can be preferably used.

  Aliphatic carboxylic acid amides that can be used include aliphatic carboxylic acid amides such as lauric acid amide, palmitic acid amide, oleic acid amide, stearic acid amide, erucic acid amide, behenic acid amide, ricinoleic acid amide and hydroxystearic acid amide. Amides, N-oleyl palmitic acid amide, N-oleyl oleic acid amide, N-oleyl stearic acid amide, N-stearyl oleic acid amide, N-stearyl stearic acid amide, N-stearyl erucic acid amide, methylol stearic acid amide, N-substituted aliphatic monocarboxylic amides such as methylol behenic acid amide, methylene bis stearic acid amide, ethylene bis lauric acid amide, ethylene bis capric acid amide, ethylene bis oleic acid amide, ethylene bis Arynic acid amide, ethylene biserucic acid amide, ethylene bis behenic acid amide, ethylene bisisostearic acid amide, ethylene bishydroxystearic acid amide, butylene bisstearic acid amide, hexamethylene bisoleic acid amide, hexamethylene bisstearic acid Amides, aliphatic carboxylic acid bisamides such as hexamethylene bisbehenic acid amide, hexamethylene bishydroxystearic acid amide, m-xylylene bisstearic acid amide, m-xylylene bis-12-hydroxystearic acid amide, N-substituted fats such as N, N'-dioleyl sebacic acid amide, N, N'-dioleyl adipic acid amide, N, N'-distearyl adipic acid amide, N, N'-distearyl sebacic acid amide Carboxylic acid bisamide Kind. Among these, compounds selected from aliphatic monocarboxylic amides, N-substituted aliphatic monocarboxylic amides and aliphatic carboxylic bisamides are preferably used. An amide of an aliphatic carboxylic acid having 4 to 30 carbon atoms, more preferably 12 to 30 carbon atoms, and an amine selected from ammonia or an aliphatic / aromatic monoamine / diamine having 1 to 30 carbon atoms is preferable. Used. In particular, palmitic acid amide, stearic acid amide, erucic acid amide, behenic acid amide, ricinoleic acid amide, hydroxy stearic acid amide, N-oleyl palmitic acid amide, N-stearyl erucic acid amide, ethylenebiscapric acid amide, ethylenebisolein A compound selected from acid amide, ethylene bis stearic acid amide, ethylene bis lauric acid amide, ethylene bis erucic acid amide, m-xylylene bis stearic acid amide and m-xylylene bis-12-hydroxy stearic acid amide is preferably used. .

  Examples of N-substituted urea that can be used include N-butyl-N′-stearyl urea, N-propyl-N′-stearyl urea, N-stearyl-N′-stearyl urea, N-phenyl-N′-stearyl urea, Examples include xylylene bisstearyl urea, toluylene bisstearyl urea, hexamethylene bisstearyl urea, diphenylmethane bisstearyl urea, diphenylmethane bislauryl urea, and the like.

  Examples of the aliphatic carboxylate that can be used include metal salts of aliphatic carboxylic acids having 4 to 30 carbon atoms, more preferably 14 to 30 carbon atoms. Specific examples of the aliphatic carboxylic acid having 14 to 30 carbon atoms include lauric acid, myristic acid, palmitic acid, oleic acid, stearic acid, isostearic acid, behenic acid, and montanic acid. Examples of the metal include lithium, sodium, potassium, magnesium, calcium, barium, aluminum, zinc, silver, copper, lead, thallium, cobalt, nickel, and beryllium. In particular, a salt of stearic acid or a salt of montanic acid is preferably used, and in particular, a compound selected from sodium stearate, potassium stearate, zinc stearate and calcium montanate is preferably used.

  Examples of the aliphatic alcohol that can be used include aliphatic alcohols having 4 to 30 carbon atoms, more preferably 15 to 30 carbon atoms. Specifically, aliphatic monoalcohols such as pentadecyl alcohol, cetyl alcohol, heptadecyl alcohol, stearyl alcohol, nonadecyl alcohol, eicosyl alcohol, ceryl alcohol, melyl alcohol, 1,6-hexanediol, 1,7 -Aliphatic polyhydric alcohols such as heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, cyclopentane-1,2-diol, cyclohexane-1,2-diol, And cyclic alcohols such as cyclohexane-1,4-diol. In particular, aliphatic monoalcohols are preferably used, and stearyl alcohol is particularly preferably used.

  Examples of aliphatic carboxylic acid esters that can be used include aliphatic carboxylic acids having 4 to 30 carbon atoms, more preferably 12 to 30 carbon atoms, and aliphatic / aromatic monools, diols and triols having 1 to 30 carbon atoms. Esters with alcohols selected from are preferably used. Specific examples include lauric acid cetyl ester, lauric acid phenacyl ester, myristic acid cetyl ester, myristic acid phenacyl ester, palmitic acid isopropyl ester, palmitic acid dodecyl ester, palmitic acid tetradecyl ester, palmitic acid pentadecyl ester, palmitic acid Aliphatic monocarboxylic acid esters such as octadecyl acid ester, cetyl palmitate, phenyl ester palmitate, phenacyl palmitate, cetyl stearate, ethyl behenate, glycol monolaurate, glycol monopalmitate, monostearate Monoesters of ethylene glycol such as acid glycol, glycol dilaurate, glycol dipalmitate, distearate Diesters of ethylene glycol such as coal, monolauric acid glycerin ester, monomyristic acid glycerin ester, monopalmitic acid glycerin ester, monostearic acid glycerin ester and other glycerin monoesters, dilauric acid glycerin ester, dimyristic acid glycerin ester, Diesters of glycerin such as glycerin dipalmitate and glyceryl distearate, glyceryl trilaurate, glyceryl trimyristate, glycerin tripalmitate, glycerin tristearate, palmitodiolein, palmitodistearin, oleodistearin And glycerin triesters. Of these, ethylene glycol diesters are preferred, and ethylene glycol distearate is particularly preferred.

  Examples of the aliphatic / aromatic carboxylic acid hydrazide that can be used include sebacic acid dibenzoic acid hydrazide, and specific examples of sorbitol compounds include dibenzylidene sorbitol, bis (p-methylbenzylidene) sorbitol, and bis (p-ethylbenzylidene). Specific examples of sorbitol, bis (3,4-dimethylbenzylidene) sorbitol, melamine compounds include melamine cyanurate and polymelate melamine, phenylphosphonic acid metal salts, phenylphosphonic acid zinc salt, phenylphosphonic acid Calcium salts and magnesium phenylphosphonic acid salts can be used.

  Examples of amino acids that can be used include glycine, alanine, valine, leucine, isoleucine, serine, threonine, cysteine, methionine, phenylglycine, tryptophan, proline, o-tyrosine, glutamic acid, asparagine, which are components constituting proteins contained in living organisms. Specific examples of acid, glutamine, asparagine, lysine, arginine, histidine, and polypeptide include leuprolide.

  These crystal nucleating agents may be used alone or in combination of two or more. When two or more types are used in combination, there may be cases where the respective synergistic effects are exhibited, and the increase in crystallization speed and the promotion of crystal refinement are more remarkable than in the case where each is used alone.

  The content of these crystal nucleating agents is preferably 0.1 to 5% by mass, more preferably 0.3 to 3% by mass, and still more preferably in the polylactic acid film or polylactic acid resin composition of the present invention. 0.5 to 2% by mass. When content is 0.1 mass% or more, it is preferable at the point which can express heat resistance and transparency. Moreover, when content is 5 mass% or less, the effect as a crystal nucleating agent is saturated and it is preferable at the point which can prevent a change of an external appearance or a physical property.

(Compound having hydrogen bonding property with crystal nucleating agent)
In the polylactic acid-type film and resin composition of this invention, it is preferable to contain the said crystal nucleating agent and the compound which has hydrogen bonding property between the said crystal nucleating agent. The exemplified crystal nucleating agent is often self-associating, and in that case, the crystal nucleating agent is added in an aggregated state in the resin, which may be inconvenient for crystal refinement. Therefore, by further mixing a compound having a hydrogen bonding property with the crystal nucleating agent, the self-association of the crystal nucleating agent may be dissolved and the crystal nucleating agent may be further finely dispersed. In this case, crystal miniaturization becomes more effective.

  There is no particular limitation on the method of adding the compound having hydrogen bonding property with the crystal nucleating agent. The compound having hydrogen bonding property with the crystal nucleating agent may be melted or mixed with polylactic acid or the crystal nucleating agent at the same time, or the one previously melted or mixed with the crystal nucleating agent is added to the polylactic acid. May be. Moreover, the method of making a master pellet and diluting it may be used. Among these, from the viewpoint of solving the self-association of the crystal nucleating agent, a method in which a compound having a hydrogen bonding property with the crystal nucleating agent is first melted or mixed with the crystal nucleating agent and added to polylactic acid. Is preferred.

  The compound that can be used as a compound having hydrogen bonding with the crystal nucleating agent may be a compound that can be used as the crystal nucleating agent, or may not be a compound that can be used as the crystal nucleating agent. Specifically, as shown below, it is confirmed whether or not it has hydrogen bonding property with the crystal nucleating agent to be used, and what has been confirmed has hydrogen bonding property with the crystal nucleating agent. What is necessary is just to use it as a compound.

Determination of whether a compound including the above-described crystal nucleating agent has hydrogen bonding property with respect to the crystal nucleating agent can be analyzed by NMR. For example, the presence or absence of a hydrogen bond can be confirmed from the chemical shift change comparing the ¹ H-NMR spectrum of a solution mixture of a compound that can be used as the crystal nucleating agent and the crystal nucleating agent, respectively. For example, when an amide compound is used as the crystal nucleating agent and a sorbitol-based compound is used as the compound having hydrogen bonding property with the crystal nucleating agent, in the case of a solution mixture, each of the simple substance comparisons, the proton peak of the amide bond is shifted in a low magnetic field And since the proton peak of the hydroxyl group of sorbitol is shifted in a high magnetic field, it can be confirmed that a hydrogen bond exists between them.

  As specific examples of the compound having hydrogen bonding property with the crystal nucleating agent, when an aliphatic carboxylic acid amide or N-substituted urea is used as the crystal nucleating agent, aliphatic alcohols, sorbitol compounds, amino acids, Polypeptides can be used. Therefore, at least one selected from the group consisting of aliphatic carboxylic acid amides and N-substituted urea is used as the crystal nucleating agent, and aliphatic alcohols are used as the compound having hydrogen bonding property with the crystal nucleating agent. It is particularly preferable to use at least one selected from the group consisting of sorbitol compounds, amino acids, and polypeptides.

  When a compound having hydrogen bonding properties with the crystal nucleating agent is contained, the amount relationship with the crystal nucleating agent is not particularly limited, but from the viewpoint of effectively releasing the self-association of the crystal nucleating agent, the crystal nucleating agent And the weight ratio of the compound having hydrogen bonding property to the crystal nucleating agent is preferably 1: 9 to 9: 1. More preferably, it is 1: 5 to 5: 1, and further preferably 1: 2 to 2: 1.

  From the viewpoint of solving the above self-association of the crystal nucleating agent and finely dispersing the crystal nucleating agent in the resin, only the crystal nucleating agent is once dissolved in a solvent and the self-association is dissolved in the resin. You can also use this method.

(Other additives)
In addition, the polylactic acid-based film and the resin composition of the present invention have additives, for example, flame retardants, heat stabilizers, light stabilizers, if necessary, as long as the effects of the present invention are not impaired. Antioxidants, anti-coloring agents, UV absorbers, antistatic agents, plasticizers, tackifiers, fatty acid esters, organic lubricants such as waxes, antifoaming agents such as polysiloxanes, and coloring agents such as pigments and dyes Can be blended.

(Crystallinity)
It is important that the polylactic acid film and the resin composition of the present invention have a crystallinity of 3 to 60%. A preferable range of crystallinity is 4 to 50%, and a more preferable range is 5 to 40%. When the crystallinity is less than 3%, the heat resistance may be insufficient. Further, when the crystallinity exceeds 60%, the transparency may be deteriorated. The degree of crystallinity can be determined by the Rrand method by performing wide-angle X-ray measurement on the polylactic acid-based resin composition and film or molded article.

(Crystal ratio obtained from strength ratio of polylactic acid)
In the polylactic acid-based film and the resin composition of the present invention, either α-crystal of polylactic acid or a crystal different from the α-crystal (α ′ crystal) is present in the film and the resin composition. Suppresses the excessive growth of crystals and finely arranges fine crystals. In this specification, 2θ is a peak in the range of (a−0.2) ° ≦ 2θ ≦ (a−0.01) ° when the 2θ peak of the α crystal is defined as a ° by X-ray diffraction. A crystal of polylactic acid having the above is called “α ′ crystal”.

  The polylactic acid-based film and the resin composition of the present invention have an α crystal of polylactic acid and 2θ of (α−0.2) ° ≦ 2θ when the 2θ peak of the α crystal is a ° by X-ray diffraction. It has both polylactic acid crystals (α ′ crystals) having a peak in the range of ≦ (a−0.01) °, and the crystal ratio obtained from the intensity ratio is 99/1 to 1/99. is important.

  When the α-crystal of polylactic acid and the 2θ peak of the α-crystal by X-ray diffraction are set to a °, the peak of 2θ is in the range of (a−0.2) ° ≦ 2θ ≦ (a−0.01) °. The preferable range of the crystal ratio obtained from the intensity ratio of the crystals (α ′ crystal) is 95/5 to 5/95, and the more preferable range is 90/10 to 10/90. When the ratio is out of the range of 99/1 to 1/99, the transparency may be insufficient.

  The above-mentioned α-crystal of polylactic acid and the peak in the range of (a−0.2) ° ≦ 2θ ≦ (a−0.01) ° when the 2θ peak of the α crystal is a ° in X-ray diffraction. There is no particular limitation on the method for causing the crystals having a phenoline to be present in the film or the resin composition, but heat treatment at a low temperature region, specifically less than 120 ° C., and a high temperature region, specifically 120 A method of crystallizing a polylactic acid resin by combining heat treatment at a temperature of 0 ° C. or higher can be used.

  The crystal ratio is determined as follows. First, the X-ray diffraction intensity is measured for a polylactic acid film or a resin composition. Next, when the main peak of the obtained X-ray diffraction pattern is α crystal and the 2θ peak of the α crystal is a °, 2θ is (a−0.2) ° ≦ 2θ ≦ (a−0). The crystals are separated into polylactic acid crystal peaks having a peak in the range of .01) °, and the crystal ratio is determined from the intensity ratio.

[Production method]
Next, the method for producing the polylactic acid film or resin composition of the present invention will be specifically described.

  The polylactic acid in the present invention can be obtained by the following method. As a raw material, a lactic acid component of L-lactic acid and / or D-lactic acid is used, but a hydroxycarboxylic acid other than the lactic acid component may be used in combination. Cyclic ester intermediates such as lactide and glycolide can also be used as raw materials. Furthermore, dicarboxylic acids and glycols can be used in combination.

  Polylactic acid can be obtained by a method of directly dehydrating and condensing the raw materials or a method of ring-opening polymerization of the cyclic ester intermediate. For example, when producing by direct dehydration condensation, lactic acid or lactic acid and hydroxycarboxylic acid are preferably subjected to azeotropic dehydration condensation in the presence of an organic solvent, preferably a phenyl ether solvent, and water is removed from the solvent distilled by azeotropic distillation. A polymer having a high molecular weight can be obtained by polymerizing by a method in which the solvent in a substantially anhydrous state except for is returned to the reaction system. It is also known that a high molecular weight polymer can be obtained by subjecting a cyclic ester intermediate such as lactide to ring-opening polymerization under reduced pressure using a catalyst such as tin octylate. At this time, a method for adjusting the conditions for removing moisture and low molecular weight compounds during heating and refluxing in an organic solvent, a method for suppressing the depolymerization reaction by deactivating the catalyst after completion of the polymerization reaction, and a method for heat-treating the produced polymer Can be used to obtain a polymer with a small amount of lactide.

  Although the method for making the polylactic acid-type film of this invention or resin composition into desired crystallinity degree is not specifically limited, For example, the following four types of methods can be utilized.

(1) Crystallization of film during film formation or after film formation During film formation, that is, temperature-falling crystallization at the base to cast part, temperature rising crystallization during heating roll conveyance or by tenter, uniaxial or biaxial Method using orientation crystallization by stretching, temperature crystallization by reheating after film formation (offline), and the like.

(2) Crystallization by preheating at the time of molding a film and a resin composition A method using crystallization by heating in molding a film and a resin composition by a molding machine.

(3) Crystallization in a heated mold after the film and the resin composition are molded The mold for molding the film and the resin composition is heated with a molding machine, and after the molding, the mold The method of crystallization above.

(4) Crystallization by heating the molded body A method of crystallizing the molded body itself in a heating oven or the like.

  These methods may be used alone, or two or more methods may be used in combination.

  Next, crystallization during film formation of the polylactic acid film, that is, crystallization at the base to cast part, and crystallization during the heating roll conveyance, and then molding the film with a molding machine An example of obtaining a body will be described in detail.

  The poly-L lactic acid resin and the poly-D lactic acid resin are dried at 100 to 120 ° C. for 3 hours or more under reduced pressure of 5 torr (5 × 133.3 Pa) or less, respectively, and the resin is supplied to the extruder, and 150 to 250 depending on the melt viscosity. Melt and knead at ℃. In addition, when obtaining the film of a multilayer structure, what is necessary is just to melt-knead at 150-250 degreeC according to melt viscosity, supplying lactic acid resin from which a composition differs to each independent separate extruder. Here, the die is cooled to 120 to 200 ° C. according to the temperature-falling crystallization temperature of the resin in order to cause the temperature-falling crystallization at the die to the cast part. It is compounded outside or inside the die and discharged from a slit-shaped die having a lip interval of 1 to 3 mm by the T-die method. The discharged resin is brought into close contact with a metal cooling casting drum by electrostatic application using a wire electrode having a diameter of 0.5 mm to obtain a non-oriented cast film.

  The surface temperature of the metal cooling roll may be set to a temperature in the vicinity of the temperature lowering crystallization temperature of the resin in order to promote the temperature lowering crystallization. A preferable range is 5 to 40 ° C, and a more preferable range is 10 to 30 ° C. By setting the surface temperature of the metal cooling roll within this range, adhesion between the metal roll and the film can be prevented, and good transparency can be exhibited.

  The non-oriented cast film thus obtained is crystallized to have a desired crystallinity by being conveyed on a heating roll. The preferable temperature range of the heating roll which becomes the highest temperature is 60 to 160 ° C, more preferably 70 to 150 ° C, and further preferably 80 to 140 ° C. The surface of the heating roll is preferably made of a material such as silicone or fluorine (for example, “Teflon (registered trademark)”) in order to prevent adhesion of the film. The final surface temperature of the film at this time is preferably 70 to 150 ° C, more preferably 80 to 140 ° C, and further preferably 90 to 130 ° C. Subsequently, the film temperature is lowered by transporting on a 0 to 50 ° C. cooling roll to obtain an unstretched film.

  When performing tenter-type sequential biaxial stretching, the non-oriented cast film obtained above is heated to a temperature at which longitudinal stretching is performed by conveying the film on a heating roll. An auxiliary heating means such as an infrared heater may be used in combination for raising the temperature. The preferable range of the stretching temperature is 70 to 95 ° C, more preferably 75 to 90 ° C. The non-oriented film heated in this way is stretched in one or two or more stages in the longitudinal direction of the film using the peripheral speed difference between the heating rolls. The total draw ratio is preferably 1.2 to 3.5 times, more preferably 1.5 to 3.0 times.

  After the film uniaxially stretched in this way is once cooled, both ends of the film are held with clips and guided to a tenter, and stretched in the width direction. The stretching temperature is preferably 70 to 95 ° C, more preferably 75 to 90 ° C. The draw ratio is preferably 1.2 to 3.5 times, more preferably 1.5 to 3.0 times. In order to reduce the difference in performance in the width direction of the film, it is preferable to stretch in the width direction at a temperature lower by 1 to 15 ° C. than the stretching temperature in the longitudinal direction. Further, if necessary, re-longitudinal stretching and / or re-lateral stretching may be performed.

  Next, this stretched film is heat-set under tension or while relaxing in the width direction. From the viewpoint of mainly imparting thermal dimensional stability to the film and from the viewpoint of reducing the amount of lactide by scattering the lactide contained in the film, the preferred heat treatment temperature is 100 to 160 ° C., more preferably 120 to 150. ° C. The heat treatment time is preferably in the range of 0.2 to 30 seconds. The relaxation rate is preferably 1 to 8%, more preferably 2 to 5%, from the viewpoint of reducing the thermal contraction rate in the width direction. More preferably, the film is once cooled before the heat setting treatment.

  Further, if necessary, the film is cooled to room temperature while being subjected to a relaxation treatment in the longitudinal and width directions, and a biaxially stretched polylactic acid film is successively obtained.

[Polylactic acid film]
Although the thickness of the polylactic acid-type film of this invention is not specifically limited, It is preferable that it is 50-2000 micrometers. More preferably, it is 100-1500 micrometers, More preferably, it is 200-1000 micrometers. When the thickness of the film is 50 μm or more, it is preferable from the standpoint of maintaining the strength of the molded body by preventing film breakage during molding. Moreover, when film thickness is 2000 micrometers or less, it is preferable from the point which can prevent the moldability and transparency by long-time heating at the time of shaping | molding.

  The polylactic acid film of the present invention may have a single layer structure or a multilayer structure composed of two or more layers. In the case of a multilayer structure, it is sufficient that at least one layer has the characteristics of the polylactic acid film of the present invention, and preferably all the layers have the characteristics of the polylactic acid film of the present invention.

  When the polylactic acid-based film of the present invention has a multi-layer structure, 2θ is (a−0.2) ° ≦ the α crystal of polylactic acid and the 2θ peak of the α crystal as a ° in X-ray diffraction. A crystal of polylactic acid having a peak in the range of 2θ ≦ (a−0.01) ° (this crystal is α ′ crystal) at a crystal ratio of 99/1 to 1/99, and crystallinity The layer which is 3 to 60% may be at least one layer in the film. More preferably, from the viewpoint of achieving both transparency and heat resistance, the other layers in the multilayer structure preferably satisfy these conditions.

  When the polylactic acid film of the present invention has a multilayer structure, the α crystal to α ′ crystal ratio is 99/1 to 1/99 and the crystallinity is 3 to 60% with respect to the total thickness of the polylactic acid film. The proportion of the layer is preferably 5 to 100%, more preferably 30 to 100%, and still more preferably 50 to 100%.

  Moreover, it is preferable that the haze of the polylactic acid-type film of this invention is 20% or less. It is 15% or less, more preferably 10% or less. By setting the haze to 20% or less, both transparency, heat resistance and impact resistance can be achieved.

  In addition, the haze as used in the field of this invention is the conversion haze value at the time of converting into thickness 0.4mm, H0.4 (%) = Hx0.4 / d (H0.4: 0.4mm thickness conversion haze value) (%), H: Actual haze value of film sample (%), d: Film sample thickness (mm) of haze measurement section) In the present invention, the converted haze value is preferably 20% or less.

  Next, as an example of a method for producing a resin composition other than the polylactic acid film in the present invention, a method for molding an injection-molded product will be described. Under reduced pressure of 5 torr (5 × 133.3 Pa) or less, dried at 100 to 120 ° C. for 3 hours or more, dry blended polylactic acid resin raw material, supplied to twin screw extruder, 150 to 250 depending on melt viscosity It is melt-kneaded at a temperature of 0 ° C. and extruded into a strand shape to produce pellets. The pellets prepared by the above method are sufficiently dried to remove moisture, and then the pellets are melted by an injection molding device and filled into a mold to obtain a polylactic acid resin composition by injection molding. The injection molding method of the present invention is not particularly limited, but typically, an injection molding method such as a general injection molding method, a gas assist molding method, and an injection compression molding method for thermoplastic resins can be employed. . In addition to the above methods, an in-mold molding method, a gas press molding method, a two-color molding method, a sandwich molding method, PUSH-PULL, SCORIM, or the like can also be employed according to other purposes. The injection molding apparatus is composed of a general injection molding machine, a gas assist molding machine, an injection compression molding machine, etc., and a molding die and ancillary equipment used therefor, a mold temperature control device, a raw material drying device, and the like. . The molding conditions are preferably such that the molten resin temperature is in the range of 170 ° C. to 210 ° C. in order to avoid thermal decomposition of the resin in the injection cylinder. When the injection mold is obtained in an amorphous state, the temperature of the molding die is as low as possible in order to shorten the cooling time of the molding cycle (mold closing to injection to holding pressure to cooling to mold opening to taking out). It is preferable to set. In general, the mold temperature is desirably 15 ° C to 55 ° C. However, in order to suppress shrinkage, warping, and deformation of the molded body during post-crystallization, it is advantageous to increase the temperature within this range.

[Molded body]
Next, a method for molding the polylactic acid film or the resin composition obtained above to obtain the molded body of the present invention will be described below.

  The molded product as used in the present invention includes a bag, a tube, a cup, a bottle, a tray, a thread, and the like, and there is no limitation on the shape, size, thickness, design, and the like. Among them, shape retainers such as blister packs used for display and packaging of products, food trays, bottles for display of beverage vending machines, containers such as lunch boxes and beverage cups, and other various packaging Various industrial materials, such as a molded object and a surface material, can be mentioned preferably.

  As a molding method, various molding methods such as vacuum molding, vacuum pressure molding, plug assist molding, straight molding, free drawing molding, plug and ring molding, skeleton molding, and the like can be applied.

  From the viewpoint of further increasing the heat resistance of the molded body, it is preferable to perform a heat treatment during or after the molding. As the method, the above-mentioned methods (2) to (4) can be used. In the crystallization by preheating at the time of molding the film or resin composition of (2), the surface temperature of the film or resin composition is the melting point (Tm) from the glass transition point (Tg) of the polylactic acid film or resin composition. It is preferable that it exists in the temperature range up to. More preferably, it is (Tg + 5) ° C. to (Tm−20) ° C., and more preferably (Tg + 10) ° C. to (Tm−40) ° C. Here, when a plurality of glass transition points are observed as a polylactic acid film, such as when the polylactic acid film is composed of a plurality of layers having different types of resins, the lowest of the glass transition points of the respective layers. The value is used as Tg, and the lowest value among the melting points of the respective layers is used as Tm.

  In the in-mold crystallization heated after molding the film or resin composition of (3), the design temperature condition of the mold is preferably (Tg + 5) ° C. to (Tm−20) ° C., more preferably (Tg + 10) ° C. To (Tm-40) ° C. Here, when a plurality of glass transition points are observed as a polylactic acid film, such as when the polylactic acid film is composed of a plurality of layers having different types of resins, the lowest of the glass transition points of the respective layers. The value is used as Tg, and the lowest value among the melting points of the respective layers is used as Tm.

  In the crystallization of the molded body by heating in (4), it is preferable that the surface temperature of the molded body is in the temperature range from the glass transition point (Tg) to the melting point (Tm) of the polylactic acid film or resin composition. When the set temperature is higher than Tm, even if crystallization is performed in a short time, the transparency of the molded body may be impaired or the shape may be distorted. When it is lower than Tg, the molded body does not crystallize, and the target crystallization may not occur.

  The polylactic acid film and resin composition of the present invention are excellent in heat resistance, impact resistance and transparency. In addition, the resin composition in the present invention includes a film and a molded body, and includes various shape retention tools such as blister packs, containers such as food trays and beverage cups that require heat resistance and transparency, and heat resistance. Can be preferably used for packaging materials such as display bottles and cans for beverage vending machines, industrial materials such as surface materials and laminates, and electronic parts conveying applications such as carrier tape.

  Hereinafter, the present invention will be described in detail based on examples, but the present invention is not necessarily limited thereto.

[Measurement method and evaluation method]
Measurements and evaluations shown in the examples were performed under the following conditions.

(1) Formability A vacuum forming machine (Forming 300X type manufactured by Seiko Sangyo Co., Ltd.) equipped with a cup-shaped aluminum mold (mold temperature 50 to 120 ° C.) having a diameter of 95 mm and a height of 7 mm is 210 mm wide. Set a sheet of polylactic acid film with a length of 300 mm and a thickness of 0.4 mm, heat the film for 15 seconds with a ceramic heater heated to 350 ° C., and vacuum press-fit the mold for 10 seconds to 10 minutes Thus, a molded body was obtained.
The obtained molded body was visually observed and evaluated according to the following criteria.
○: The edge can be formed at a right angle. Δ: The edge portion is slightly rounded. X: The shape of the mold is remarkably different.
Among the above evaluations, ◯ and Δ were acceptable.

(2) Crystallinity The film or the molded body molded in (1) is cut to an appropriate size and fixed to an aluminum sample holder (20 mm x 18 mm x 0.15 mm). X-ray measurement was performed.

  RU-200R (rotary anti-cathode type) manufactured by Rigaku Corporation as an X-ray generator (X-ray source: CuKα ray (using curved crystal monochromator), output: 50 kV, 200 mA), Rigaku Denki Co., Ltd. as a goniometer 2155D type (slit: 1 ° -0.15 mm-1 ° -0.45 mm, detector: scintillation counter) manufactured by Rigaku Electric Co., Ltd. as a counting recording device Wide angle X-ray measurement was performed at 2θ / θ: continuous scan, measurement range: 2θ = 5 to 145 °, step: 0.02 °, scanning speed: 2 ° / min, and the crystallinity was determined by the Rand method.

(3) Layer thickness ratio A film or a cross-section of the molded body molded in (1) was photographed with transmitted light using a metal microscope Leica DMLM manufactured by Leica Microsystems Co., Ltd., and the thickness of each layer was measured. .

  In order to facilitate cross-sectional observation, the measurement was performed after heating or crystallizing the film or molded body as necessary.

(4) Haze The haze value of the film or the molded article formed in (1) was measured using a turbidimeter (NDH5000, manufactured by Nippon Denshoku Industries Co., Ltd.). The measurement was performed 5 times per level, and the haze value (%) was determined as a converted value when the thickness was 0.4 mm from the average value of the 5 measurements. The conversion formula is as follows.
H _0.4 (%) = H × 0.4 / d
here,
H _0.4 : 0.4 mm thickness converted haze value (%)
H: Actual value (%) of haze of film or molded body sample
d: Sample thickness (mm) of haze measurement part of film or molded product

(5) Heat resistance The molded article was visually evaluated for deformation when placed in an oven set at 60 ° C for 2 hours.
○: No deformation Δ: Small deformation ×: Large deformation
Among the above evaluations, ◯ and Δ were acceptable.

(6) Impact resistance Ten strip samples of 10 mm x 50 mm were made from the film or the molded body molded in (1), and the strip samples were slowly folded 180 ° so that the length of 50 mm was halved. Based on the sample shape, the following criteria were used.
○: Neither 10 breaks (breaks)
Δ: The number of unbreakable samples is 1 or more and 9 or less.
Among the above evaluations, ◯ and Δ were acceptable.

(7) When the main peak of the X-ray diffraction pattern measured in the same manner as in the crystal ratio (2) is α crystal and the 2θ peak of the α crystal is a °, 2θ is (a−0.2) The crystals were separated into polylactic acid crystal peaks having a peak in the range of ° ≦ 2θ ≦ (a−0.01) °, and the crystal ratio was determined from their intensity ratio. Note that the Pseudo-Voigt function was used for peak separation, the 2θ position of the α crystal was fixed at 16.7 °, and the peak height and shape factor were refined. When the 2θ peak of the α crystal is a °, 2θ is 2θ for the polylactic acid crystal having a peak in the range of 2θ (a−0.2) ° ≦ 2θ ≦ (a−0.01) °, and the peak height Now we refined the parameters of the shape factor.

[Polylactic acid resin]
It shows about the polylactic acid resin used in the Example.
P-1:
Poly-L-lactic acid resin P-2 having a D-lactic acid unit content of 1 mol% and a weight average molecular weight of 190,000 in terms of PMMA:
Poly-L-lactic acid resin P-3 having a D-lactic acid unit content ratio of 5 mol% and a weight average molecular weight of 190,000 in terms of PMMA:
What mixed P-1 and the poly D-lactic acid resin (L-lactic acid unit content rate 1 mol%) of the weight average molecular weight 10,000 of PMMA conversion by mass ratio 90:10.
P-4:
What mixed P-1 and the poly D-lactic acid resin (L-lactic acid unit content rate 1 mol%) of the weight average molecular weight 10,000 of PMMA conversion by mass ratio 60:40.

[Crystal nucleating agent or compound having hydrogen bonding property with crystal nucleating agent]
The crystal nucleating agent used in the examples or the compound having hydrogen bonding property with the crystal nucleating agent will be described.
Q-1:
Ethylene bislauric acid amide (EBLA)
Q-2:
Ethylene bis-stearic acid amide (EBSA)

Q-3:
Bis (p-methylbenzylidene) sorbitol When an amide compound is used as the crystal nucleating agent and a sorbitol-based compound is used as the compound having hydrogen bonding property with the crystal nucleating agent, each of the solution mixtures is compared with each of the simple substance The proton peak of the bond is shifted in a low magnetic field, and the proton peak of the hydroxyl group of sorbitol is shifted in a high magnetic field, confirming the presence of a hydrogen bond between them.

[Production of polylactic acid film and molded product]
Example 1
Polylactic acid resin (P-1) and ethylenebislauric acid amide (Q-1) were supplied to a vent type twin screw extruder at a mass ratio of 99: 1 and extruded from a T die die having a die temperature set at 200 ° C. By an electrostatic application method, it was brought into close contact with a casting drum at 30 ° C. and solidified by cooling to obtain a non-oriented cast film.

  Subsequently, the non-oriented cast film was transported on a silicone roll heated to 90 ° C. so that the contact time was 30 seconds, and then transported on a cooling roll at 30 ° C. A 40 mm non-oriented film was obtained.

  Next, the obtained non-oriented film is cut into a sheet sample, set in a vacuum forming machine, heated for 15 seconds with a ceramic heater heated to 350 ° C., and then placed in an aluminum mold set at 50 ° C. for 10 seconds. A cylindrical container having a diameter of 95 mm and a height of 7 mm was obtained by vacuum pressing.

  The obtained molded article had good heat resistance, transparency and impact resistance.

(Example 2, 6-9)
The same procedure as in Example 1 was performed except that the polylactic acid resin and the crystal nucleating agent constituting the film were changed as shown in Tables 1 and 2.

(Example 3)
The non-oriented film obtained in the same manner as in Example 1 was cut into single-wafer samples, set in a vacuum forming machine, heated for 15 seconds with a ceramic heater heated to 350 ° C., and then set to 90 ° C. The mold was vacuum-pressed for 60 seconds to obtain a molded body having the same shape as in Example 1.

  The obtained molded article had good heat resistance, transparency and impact resistance.

Example 4
Polylactic acid resin (P-1) and ethylenebislauric acid amide (Q-1) were supplied to a vent type twin screw extruder at a mass ratio of 99: 1 and extruded from a T die die having a die temperature set at 200 ° C. By an electrostatic application method, it was brought into close contact with a casting drum at 30 ° C. and solidified by cooling to obtain a non-oriented cast film.

  Subsequently, the non-oriented cast film was transported on a silicone roll heated to 90 ° C. so that the contact time was 120 seconds, and then transported on a cooling roll at 30 ° C. A 40 mm non-oriented film was obtained.

  Next, the obtained non-oriented film is cut into a sheet sample, set in a vacuum forming machine, heated for 15 seconds with a ceramic heater heated to 350 ° C., and then placed in an aluminum mold set at 50 ° C. for 10 seconds. A molded body having the same shape as in Example 1 was obtained by vacuum pressure bonding.

  The obtained molded article had good heat resistance, transparency and impact resistance.

(Example 10)
The polylactic acid resin (P-3) and ethylenebislauric acid amide (Q-1) were supplied to a vent type twin screw extruder at a mass ratio of 99: 1, melt-kneaded at 200 ° C, and then cooled to 180 ° C. The film was extruded from a die die, and brought into close contact with a casting drum at 30 ° C. by an electrostatic application method and solidified by cooling to obtain a non-oriented cast film.

  Subsequently, the non-oriented cast film was conveyed on a silicone roll heated to 120 ° C. so that the contact time was 10 seconds, and then conveyed on a cooling roll at 30 ° C. A 40 mm non-oriented film was obtained.

  Next, the obtained non-oriented film is cut into a sheet sample, set in a vacuum forming machine, heated for 15 seconds with a ceramic heater heated to 350 ° C., and then placed in an aluminum mold set at 50 ° C. for 10 seconds. A molded body having the same shape as in Example 1 was obtained by vacuum bonding.

  The obtained molded article had good heat resistance, transparency and impact resistance.

(Example 11)
The same operation as in Example 10 was carried out except that the polylactic acid resin constituting the film was changed as shown in Table 2.

(Example 12)
As a resin for the layer A, a polylactic acid resin (P-1) and ethylenebislauric acid amide (Q-1) at a mass ratio of 99: 1, and as a resin for the layer B, a polylactic acid resin (P- 2) and ethylene bislauric acid amide (Q-1) at a mass ratio of 99: 1, respectively, are supplied to separate vent type twin screw extruders, melted and kneaded at 200 ° C., and the layer structure is A / B / A The resulting composite was coextruded from a T-die die, and brought into close contact with a casting drum at 30 ° C. by an electrostatic application method and solidified by cooling to obtain a non-oriented cast film.

  Subsequently, the non-oriented cast film was transported on a silicone roll heated to 90 ° C. so that the contact time was 30 seconds, and then transported on a cooling roll at 30 ° C. A 40 mm non-oriented film was obtained.

  Next, the obtained non-oriented film is cut into a sheet sample, set in a vacuum forming machine, heated for 15 seconds with a ceramic heater heated to 350 ° C., and then placed in an aluminum mold set at 50 ° C. for 10 seconds. A molded body having the same shape as in Example 1 was obtained by vacuum bonding.

  The obtained molded article had good heat resistance, transparency and impact resistance.

(Examples 13 and 14)
The same operation as in Example 12 was performed except that the polylactic acid resin and the crystal nucleating agent constituting the film were changed as shown in Table 2.

(Example 15)
As a resin for the layer A, a polylactic acid resin (P-3) and ethylenebislauric acid amide (Q-1) at a mass ratio of 99: 1, and as a resin for the layer B, a polylactic acid resin (P- 2) and ethylene bislauric acid amide (Q-1) at a mass ratio of 99: 1, respectively, are supplied to separate vent type twin screw extruders, melted and kneaded at 200 ° C., and the layer structure is A / B / A The resulting composite was co-extruded from a T-die die cooled to 180 ° C., and brought into close contact with a 30 ° C. casting drum by an electrostatic application method to cool and solidify to obtain a non-oriented cast film.

  Subsequently, the non-oriented cast film was transported on a silicone roll heated to 90 ° C. so that the contact time was 30 seconds, and then transported on a cooling roll at 30 ° C. A 40 mm non-oriented film was obtained.

  Next, the obtained non-oriented film is cut into a sheet sample, set in a vacuum forming machine, heated for 15 seconds with a ceramic heater heated to 350 ° C., and then placed in an aluminum mold set at 50 ° C. for 10 seconds. A molded body having the same shape as in Example 1 was obtained by vacuum bonding.

  The obtained molded article had good heat resistance, transparency and impact resistance.

(Example 16)
Polylactic acid resin (P-1) and ethylenebislauric acid amide (Q-1) were supplied to a vent type twin screw extruder at a mass ratio of 99: 1 and extruded from a T die die having a die temperature set at 200 ° C. By an electrostatic application method, it was brought into close contact with a casting drum at 30 ° C. and solidified by cooling to obtain a non-oriented cast film.

  Subsequently, the non-oriented cast film was transported on a silicone roll heated to 90 ° C. so that the contact time was 30 seconds, and then transported on a cooling roll at 30 ° C. A 40 mm non-oriented film was obtained.

  Next, this non-oriented film is conveyed again on a silicone roll heated to 120 ° C. so that the contact time is 10 seconds, and then is conveyed on a cooling roll at 30 ° C. A non-oriented film of 0.40 mm was obtained.

  The obtained film had good heat resistance, transparency and impact resistance.

(Example 17)
As a resin for the layer A, a polylactic acid resin (P-1) and ethylenebislauric acid amide (Q-1) at a mass ratio of 99: 1, and as a resin for the layer B, a polylactic acid resin (P- 2) and ethylene bislauric acid amide (Q-1) at a mass ratio of 99: 1, respectively, are supplied to separate vent type twin screw extruders, melted and kneaded at 200 ° C., and the layer structure is A / B / A The resulting composite was coextruded from a T-die die, and brought into close contact with a casting drum at 30 ° C. by an electrostatic application method and solidified by cooling to obtain a non-oriented cast film.

  Subsequently, the non-oriented cast film was transported on a silicone roll heated to 90 ° C. so that the contact time was 30 seconds, and then transported on a cooling roll at 30 ° C. A 40 mm non-oriented film was obtained.

  Next, this non-oriented film is conveyed again on a silicone roll heated to 120 ° C. so that the contact time is 10 seconds, and then is conveyed on a cooling roll at 30 ° C. A non-oriented film of 0.40 mm was obtained.

  The obtained film had good heat resistance, transparency and impact resistance.

  The results of the above examples are shown in Tables 1 and 2.

(Comparative Example 1)
Polylactic acid resin (P-1) is supplied to a vent type twin screw extruder, extruded from a T die die with a die temperature set at 200 ° C., and is brought into close contact with a 30 ° C. casting drum by an electrostatic application method and solidified by cooling. A non-oriented cast film having a thickness of 0.40 mm was obtained.

  Next, the obtained non-oriented film is cut into a sheet sample, set in a vacuum forming machine, heated for 15 seconds with a ceramic heater heated to 350 ° C., and then placed in an aluminum mold set at 50 ° C. for 10 seconds. A molded body having the same shape as in Example 1 was obtained by vacuum bonding.

  The crystallinity of the obtained molded product was not within the scope of the present invention, and the heat resistance of the molded product was insufficient.

(Comparative Example 2)
The non-oriented film obtained in the same manner as in Example 1 was cut into single-wafer samples, set in a vacuum forming machine, heated for 15 seconds with a ceramic heater heated to 350 ° C., and then set to 120 ° C. The mold was vacuum-bonded for 10 minutes to obtain a molded body having the same shape as in Example 1.

  The haze of the obtained molded product was not within the scope of the present invention, and the transparency and heat resistance of the molded product were insufficient.

(Comparative Example 3)
The non-oriented cast film obtained in the same manner as in Example 1 was conveyed on a silicone roll heated to 120 ° C. so that the contact time was 60 seconds, and then conveyed on a cooling roll at 30 ° C. The temperature was lowered to obtain a non-oriented film having a thickness of 0.40 mm.

  Next, the obtained non-oriented film is cut into a sheet sample, set in a vacuum forming machine, heated for 15 seconds with a ceramic heater heated to 350 ° C., and then placed in an aluminum mold set at 50 ° C. for 10 seconds. A molded body having the same shape as in Example 1 was obtained by vacuum bonding.

  The crystallinity and haze of the obtained molded product were not within the scope of the present invention, and the moldability of the film as the material of the molded product and the transparency of the molded product were insufficient.

The results of the above comparative examples are shown in Table 2.

    In Examples 1 and 2 in which the polylactic acid resin and the crystal nucleating agent constituting the film are the same and only the composition ratio is different, the moldability is inferior in Example 1 in which the composition ratio is in a more preferable range. However, the molded body obtained in Example 1 is superior to the molded body in Example 2 in heat resistance and impact resistance.

  It can be seen that Examples 1 and 6, which differ only in the type of crystal nucleating agent constituting the film, are excellent in film moldability, heat resistance of the molded body, and impact resistance. Moreover, the haze of the film and the haze of the molded product were both small.

  The film of Example 7 containing polylactic acid constituting the film, a crystal nucleating agent and a compound having hydrogen bonding properties with the crystal nucleating agent has a smaller haze than the film and molded article of Example 1. I understand that.

  It can be seen that Examples 1 and 9, which differ only in the type of polylactic acid constituting the film, are excellent in film moldability, heat resistance of the molded body, and impact resistance. Moreover, the haze of the film and the haze of the molded product are both small and excellent in transparency.

  The molded product of Example 3 in which the crystallinity was improved by heat-treating the film of Example 1 had a higher haze value than that of Example 1, because the crystallinity of the molded product was higher.

  It can be seen that the films of Examples 4, 5, and 16 having different film production methods compared to Example 1 are excellent in film moldability, heat resistance of the molded article, and impact resistance as in Example 1. . Moreover, the haze of the film and the haze of the molded product were both small.

  Also in the film of Example 9 in which the polylactic acid constituting the film, the crystal nucleating agent, and the film production method are different from those in Example 1, the film formability, the heat resistance of the molded body, and the impact resistance are the same as in Example 1. It turns out that it is excellent in property. Moreover, the haze of the film and the haze of the molded product were both small.

  In the polylactic acid constituting the film as compared with Example 1 and the films of Examples 10 and 11 having different film production methods, the film formability, the heat resistance of the molded body, and the impact resistance are the same as in Example 1. It turns out that it is excellent. Moreover, the haze of the film and the haze of the molded product were both small.

  In Examples 12 to 15 and 17 having a two-layer structure, it can be seen that the film formability, the heat resistance of the molded article, and the impact resistance are excellent as in Example 1. Moreover, the haze of the film and the haze of the molded product were both small.

  The film of Comparative Example 1 containing no crystal nucleating agent did not have crystallinity and was excellent in moldability, but the heat resistance of the molded body was inferior.

  The film and molded body of Comparative Example 2 obtained in the same manner as in Example 1 except that no crystal nucleating agent is contained, the haze exceeds the range of the present invention, the molded body has poor transparency, and heat resistance The properties are also lower than those of Example 1.

  The film of Comparative Example 3 containing no α ′ crystal had poor moldability and high haze. The molded product of Comparative Example 3 having a crystallinity of 70% obtained from this had a haze higher than the range of the present invention and poor transparency.

  The polylactic acid-based film and resin composition of the present invention are used for shape display such as blister packs used for display and packaging of products, food trays, bottles for display of beverage vending machines, lunch boxes and beverages. It can be applied to a wide range of applications, including containers such as cups, various industrial materials such as various molded articles for packaging, and surface materials.

The film made of the polylactic acid-based resin composition of the present invention can be applied to various molding methods such as vacuum molding, vacuum / pressure molding, plug assist molding, straight molding, free drawing molding, plug and ring molding, skeleton molding, and the like. Have sex. Moreover, it can use especially preferably for packaging materials, such as various shape-retaining tools and containers with which heat resistance, transparency, and impact resistance are requested | required.

Claims (12)

A molded body having a crystallinity,
The molded body has an α crystal of polylactic acid, and 2θ is (a−0.2) ° ≦ 2θ ≦ (a−0.01) when the 2θ peak of the α crystal is a ° in X-ray diffraction. ) Crystal of polylactic acid having a peak in the range of ° (this crystal is called α ′ crystal), and the crystal ratio obtained from the intensity ratio of α crystal and α ′ crystal is 99/1 to 1/99 There, and Ri crystallinity of 3-60% der,
A molded article obtained by combining a heat treatment at a temperature of less than 120 ° C and a heat treatment at a temperature of 120 ° C or more with respect to a polylactic acid film . The compact contains a crystal nucleating agent, molded product according to claim 1. The molded article according to claim 2, wherein the crystal nucleating agent is at least one selected from the group consisting of aliphatic carboxylic acid amides and N-substituted ureas. The molded body contains a compound having a crystal nucleating agent and the hydrogen-bonding, molding according to claim 2 or 3. The molded article according to claim 4, wherein the compound having hydrogen bonding property with the crystal nucleating agent is at least one selected from the group consisting of aliphatic alcohols, sorbitol compounds, amino acids, and polypeptides. . The molded body has a haze of 20% or less, the molded body according to any one of claims 1 to 5. A polylactic acid-based film having crystallinity,
The polylactic acid-based film has an α crystal of polylactic acid, and 2θ is (a−0.2) ° ≦ 2θ ≦ (a−0) when the 2θ peak of the α crystal is set to a ° by X-ray diffraction. .01) ° polylactic acid crystal having a peak in the range (this crystal is referred to as α ′ crystal), and the crystal ratio obtained from the intensity ratio of α crystal and α ′ crystal is 99/1 to 1 / 99, and, Ri crystallinity of 3-60% der,
A polylactic acid film obtained by combining a heat treatment at a temperature of less than 120 ° C. and a heat treatment at a temperature of 120 ° C. or higher . The polylactic acid film according to claim 7 , wherein the polylactic acid film contains a crystal nucleating agent. The polylactic acid film according to claim 8 , wherein the crystal nucleating agent is at least one selected from the group consisting of an aliphatic carboxylic acid amide and an N-substituted urea. The polylactic acid film according to claim 8 or 9 , wherein the polylactic acid film contains a compound having hydrogen bonding properties with the crystal nucleating agent. The polylactic acid according to claim 10 , wherein the compound having hydrogen bonding property with the crystal nucleating agent is at least one selected from the group consisting of aliphatic alcohols, sorbitol compounds, amino acids, and polypeptides. Film. The polylactic acid film according to any one of claims 7 to 11 , wherein the polylactic acid film has a haze of 20% or less.