JPH11116783A - Molding and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polylactic acid resin molding having both transparency and crystallinity (heat resistance). SOLUTION: There is provided a polylactic acid resin molding containing a polylactic acid resin (A) and at least one transparentizing agent (B) selected from the group consisting of compounds represented by the formula (wherein R<1> and R<2> are each a 1-30C saturated or unsaturated hydrocarbon group and is a linear or branched hydrocarbon group; and n is an integer of 1-4), containing 94-99 wt.%, based on the total amount of components A and B, component A and 6-1 wt.% component B and having transparency and heat resistance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a polylactic acid-based resin molded article containing a polylactic acid-based resin (A) and a clarifying agent (B) having a specific chemical structure. Based on the total weight of (A) and the clarifying agent (B), the polylactic acid-based resin (A) is contained in an amount of 94 to 99% by weight, and the clarifying agent (B) is included in an amount of 6 to 1% by weight. ,And,
The present invention relates to a polylactic acid resin molded article having both transparency and heat resistance, and a method for producing the same.

[0002]

2. Description of the Related Art Recently, general-purpose plastics are disposed of semi-permanently even when buried, because they increase the amount of garbage when disposed after use and are hardly decomposed in the natural environment. Abandoned plastics have caused problems such as spoiling the landscape and destroying the living environment of marine life. On the other hand, as polymers having thermoplasticity and degradability, polyhydroxycarboxylic acids such as polylactic acid, and aliphatic polyhydric alcohols such as polybutylene succinate and aliphatic polycarboxylic acids derived from aliphatic polycarboxylic acids. Polyester and the like have been developed. Some of these polymers degrade 100% within a few months to one year in the body of an animal and, when placed in soil or seawater, begin to degrade in a few weeks in a humid environment, about one year Has disappeared in a few years, and its decomposition products are becoming harmless to humans because they have the property of becoming lactic acid, carbon dioxide, and water, and are attracting attention as a substitute for medical materials and general-purpose resins. .

On the other hand, in recent years, electronics, mechatronics, optoelectronics, lasers (optical communication,
CD-ROM, CD-R, LDNDVD) magneto-optical recording and the like are also included. ), Liquid crystal, optics, office automation (OA), factory automation, etc., and with the rapid development of technology, the demand for transparent plastic films is increasing, and the applications thereof are also expanding dramatically. Specific examples of the uses include, for example, uses for films for overhead projectors, films for plate making, tracing films, food wrapping films, agricultural films, and the like. Specific examples of high-performance applications include, for example, transparent conductive films (for example, screen touch panels for computer input), heat ray reflective films, films for liquid crystal displays, polarizing films for liquid crystal displays, and PCBs (printed circuit boards). No.

Conventionally, hard films having low flexibility (flexibility) such as glass, acrylic (polymethyl methacrylate, PMMA) and polycarbonate (PC) have been used for these applications. In the use of, there is a tendency that replacement with a transparent film excellent in flexibility, moldability, heat resistance and the like is required.
Some of these alternative demands can be met with polyethylene terephthalate (PET) films. However, for applications where degradability is required, PET may be a problem. From such a background, in the technical field of transparent films, it is expected that a transparent film having both transparency / heat resistance (crystallinity) / decomposability will play a significant role. by the way,
Molded products of aliphatic polyesters such as polylactic acid, which is a degradable thermoplastic polymer, lactic acid and other aliphatic hydroxycarboxylic acids and / or copolymers of aliphatic polyhydric alcohols and aliphatic polycarboxylic acids (for example, three-dimensional) Molded products such as bottles having a two-dimensional shape, unstretched films or sheets having a two-dimensional shape, and unstretched filaments or yarns having a one-dimensional shape) are usually amorphous immediately after molding. In addition, since there is almost no crystal having a size equal to or larger than the wavelength of light that causes light scattering, the crystal is transparent. However, since this transparent molded body is usually amorphous, it has poor heat resistance.

[0005] For example, amorphous polylactic acid containers have excellent transparency but low heat resistance, so that hot water or microwave ovens cannot be used, and their applications have been limited. For this reason,
In order to improve the heat resistance, the crystallinity is filled by filling in a mold kept near the crystallization temperature during molding, or by heat treatment (annealing) of the amorphous molded product after molding. In general, a crystal (for example, spherulite) having a size equal to or larger than the wavelength of light that causes light scattering is rapidly grown, and the crystal is grown to a size larger than the wavelength of visible light. However, the molded article becomes opaque.

As described above, according to the conventional technology,
It is not possible to simultaneously impart transparency and crystallinity to a polylactic acid-based resin molded article such as polylactic acid or a copolymer of lactic acid and other aliphatic hydroxycarboxylic acid and / or an aliphatic polyhydric alcohol and an aliphatic polycarboxylic acid. However, it is difficult, as if it were a trade-off, and there is no polylactic acid-based resin molded article having both transparency and crystallinity (heat resistance).

On the other hand, in the technical field relating to general-purpose resins, a technique is known in which the addition of a transparent nucleating agent (clearing crystal nucleating agent) controls the growth of spherulites and simultaneously imparts transparency to a molded article. ing. The clarifying agent, for the crystals,
Action to suppress excessive growth in "size", "number"
And a promoting effect on the “crystallization rate”. Specific examples thereof include, for example, a technique for imparting transparency to a polypropylene resin molded article by adding a sorbitol derivative to a polypropylene resin, and for promoting the crystallization rate of polyethylene terephthalate.
Examples thereof include a method of adding an aromatic polyester fine powder containing terephthalic acid and resorcin as main constituent units. However, in the technical field related to aliphatic polyesters, transparent nucleating agents suppress excessive growth of crystals in “size”, increase in “number”, promote in “crystallization rate”, and A technique for simultaneously imparting transparency and crystallinity to a molded article is not known.

[Action mechanism of transparent nucleating agent] The mechanism of the development of transparency by the transparent nucleating agent in the crystalline resin molded article is not always clear. Also, the present invention is not bound by any particular mechanism or hypothesis. When a transparent nucleating agent is added to make a crystalline resin molded article transparent, it is usually necessary to appropriately set conditions for crystal growth (for example, crystallization temperature, crystallization time, and the like). The mechanism of the development of transparency by the transparent nucleating agent in the crystalline resin molded article can be explained by the following model, for example.

Model of Crystalline Resin Mold without Addition of Transparent Nucleating Agent When the resin molding is crystallized without adding the transparent nucleating agent, the crystal is compared with a metal having the transparent nucleating agent added. Since there are few crystal nuclei that are a stepping stone for growth, a relatively small number of spherulites are generated, and as a result, the size of each spherulite becomes relatively overwhelmingly large. That is, as compared with the case where a transparent nucleating agent is added per unit volume, relatively few large crystals are generated even with the same degree of crystallinity, and as a result, the size is about the same as or larger than the wavelength of visible light. Crystals are formed, and visible light is scattered so as not to go straight, so that the crystalline resin molded body to which the transparent nucleating agent is not added becomes opaque.

Model of Crystalline Resin Mold with Added Transparent Nucleating Agent When the resin molded body is crystallized by adding the transparent nucleating agent, the transparent nucleating agent forms a crystal nucleus that can hinder crystal growth. Therefore, compared with the case where the transparent nucleating agent is not added, relatively overwhelmingly large number of crystals are generated, and as a result, the size of each crystal can be relatively overwhelmingly small. it can. That is, per unit volume,
Compared with the case where the transparent nucleating agent is not added, even with the same crystallinity, a relatively large number of small crystals are generated,
As a result, a crystal having a shape considerably smaller than the wavelength of visible light is generated, and the visible light is allowed to travel straight without being scattered. Therefore, the crystalline resin molded article to which the transparent nucleating agent is added can be made transparent.

[Transparent Nucleating Agent for Aliphatic Polyester] The present inventors have conceived that it is a very significant problem to make a molded article of a polylactic acid resin exhibit transparency and crystallinity at the same time. Conventionally, the person skilled in the art has never recognized the location of such a problem by the present inventors. The present inventors, from such a viewpoint,
A transparent nucleus for a polypropylene resin as a transparent nucleating agent for a polylactic acid-based resin such as polylactic acid or a copolymer of lactic acid and other aliphatic hydroxycarboxylic acids and / or an aliphatic polyhydric alcohol and an aliphatic polycarboxylic acid. Injection molding using sorbitol derivatives, sorbitol derivatives, phosphorus-based nucleating agents, talc, silica, calcium lactate, sodium benzoate, etc. And crystallinity could not be imparted at the same time. As described above, polylactic acid-based resins such as polylactic acid and copolymers of lactic acid and other aliphatic hydroxycarboxylic acids and / or aliphatic polyhydric alcohols and aliphatic polycarboxylic acids are commonly used for injection molding and blow molding. In molding techniques such as compression molding, it is difficult to simultaneously exhibit transparency and crystallinity (heat resistance) even at the time of molding or before and after molding, even if a known and used transparent nucleating agent is used.

[0012]

SUMMARY OF THE INVENTION An object of the present invention is to provide a polylactic acid-based resin molded article such as polylactic acid, which has both transparency and crystallinity (heat resistance).

[0013]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, added a compound having a specific chemical structure to a polylactic acid-based resin, and formed a molded article at or after molding. It has been found that a crystal having both transparency and crystallinity (heat resistance) can be obtained by crystallizing the compound, thereby completing the present invention. The present invention is specified by the following items [1] to [15].

[1] A polylactic acid-based resin containing a polylactic acid-based resin (A) and at least one transparentizing agent (B) selected from the group of compounds represented by the general formula (1) [Formula 3] A molded article, wherein the polylactic acid-based resin (A) is 94 to 99% by weight based on the total weight of the polylactic acid-based resin (A) and the clarifying agent (B), and the clarifying agent is A polylactic acid-based resin molded product containing (B) in an amount of 6 to 1% by weight and having both transparency and heat resistance.

[0015]

Embedded image (In the general formula (1), R ¹ and R ^{2 each} have 1 to 1 carbon atoms.
It is a saturated or unsaturated hydrocarbon, linear or branched hydrocarbon group of 30 and n is an integer of 1-4. [2] The polylactic acid-based resin is at least one selected from the group consisting of polylactic acid, a copolymer having a polylactic acid block and a polybutylene succinate block, and a copolymer having a polylactic acid block and a polycaproic acid block. The polylactic acid resin molded article according to [1].

[3] The at least one clarifying agent (B) selected from the group of compounds represented by the general formula (1) [formula 3] is diisodecyl adipate as described in [1] or [2]. Polylactic acid resin molded article. [4] The polylactic acid-based resin molded article according to any one of [1] to [3], wherein transparency is equivalent to a haze value of 1 mm thickness being 30% or less. [5] The polylactic acid-based resin molded article according to any one of [1] to [4], wherein the heat resistance is exhibited by crystallinity having a crystallinity of 10% or more.

[6] Heat resistance, Vicat softening point is 1
The polylactic acid-based resin molded product according to any one of [1] to [4], which corresponds to a temperature of 00 to 160 ° C. [7] A polylactic acid-based resin molded article containing a polylactic acid-based resin (A) and at least one transparentizing agent (B) selected from the group of compounds represented by the general formula (1) [Formula 4] A method for producing, wherein the polylactic acid-based resin (A) is 94 to 99% by weight based on the total weight of the polylactic acid-based resin (A) and the clarifying agent (B), and the clarifying agent is used. When molding a polylactic acid-based resin composition containing 6 to 1% by weight of (B), heat treatment is performed during or after molding, and polylactic acid having both transparency and heat resistance. A method for producing a resin-based molded article.

[0018]

Embedded image (In the general formula (1), R ¹ and R ^{2 each} have 1 to 1 carbon atoms.
It is a saturated or unsaturated hydrocarbon, linear or branched hydrocarbon group of 30 and n is an integer of 1-4. [8] In the heat treatment method, after once melting the polylactic acid-based resin composition, the polylactic acid-based resin composition is filled into a mold kept in a temperature range from a crystallization start temperature to a crystallization end temperature. The production method according to [7], wherein the crystallization is performed. [9] In the heat treatment method, after the melt of the polylactic acid-based resin composition is cooled and solidified in a mold to obtain an amorphous molded body, the molded body is subjected to a glass transition of the polylactic acid-based resin (A). [7] characterized in that it is crystallized in a temperature range from a temperature to a melting point.
Production method described in 1.

[10] The polylactic acid-based resin is polylactic acid,
Any one of [7] to [9], which is at least one selected from the group consisting of a copolymer having a polylactic acid block and a polybutylene succinate block, and a copolymer having a polylactic acid block and a polycaproic acid block. Manufacturing method described. [11] The method according to any one of [7] to [10], wherein the at least one clarifying agent (B) selected from the group of compounds represented by the general formula (1) [Formula 4] is diisodecyl adipate. Production method. [12] The production method according to any one of [7] to [11], wherein transparency is equivalent to a haze value of 1 mm thickness being 30% or less.

[13] The heat resistance is exhibited by crystallinity having a degree of crystallinity of 10% or more. [7]
Or the production method according to any one of [12] to [12]. [14] Heat resistance, Vicat softening point is 100-16
The production method according to any one of [7] to [12], which corresponds to 0 ° C. [15] A polylactic acid-based resin molded article having both transparency and heat resistance, obtained by the production method according to any one of [7] to [14].

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. [Polylactic acid-based resin] In the present invention, polylactic acid-based resin refers to polylactic acid, a copolymer of lactic acid and hydroxycarboxylic acid (for example, a copolymer of lactic acid and glycolic acid, a copolymer of lactic acid and caproic acid, and a copolymer of polylactic acid and polycaproic acid). A copolymer of lactic acid and an aliphatic polyhydric alcohol and an aliphatic polycarboxylic acid (for example, a copolymer of lactic acid and butanediol with succinic acid and adipic acid, a copolymer of lactic acid with ethylene glycol and a copolymer of butanediol and succinic acid), Block copolymers of polylactic acid and polybutylene succinate), and mixtures thereof. In the case of a mixture, a compatibilizer may be contained. When the polylactic acid-based resin is a copolymer, the mode of arrangement of the copolymer may be any mode such as a random copolymer, an alternating copolymer, a block copolymer, and a graft copolymer. Furthermore, these may be at least partially cross-linked with a cross-linking agent such as xylylene diisocyanate, polyvalent isocyanate such as 2,4-tolylene diisocyanate or polysaccharide such as cellulose, acetyl cellulose or ethyl cellulose. At least a part thereof may have any structure such as a linear, annular, branched, star, and three-dimensional network structure, and there is no limitation.

In the polylactic acid resin of the present invention, polylactic acid, particularly poly-L-lactic acid, polycaproic acid, particularly poly-lactic acid
ε-caproic acid, a block copolymer of polylactic acid and poly-6-hydroxycaproic acid, particularly a block copolymer of poly-L-lactic acid and poly-6-hydroxycaproic acid,
Preference is given to block copolymers of polylactic acid and polybutylene succinate, especially block copolymers of poly-L-lactic acid and polybutylene succinate.

[Aliphatic hydroxycarboxylic acid] Specific examples of the aliphatic hydroxycarboxylic acid constituting the polylactic acid resin in the present invention include, for example, glycolic acid, lactic acid, 3-hydroxy drank acid, 4-hydroxy drank acid, 4-hydroxyvaleric acid, 5-hydroxyvaleric lactic acid, 6-hydroxycaproic acid and the like. These may be one kind or a mixture of two or more kinds. When the aliphatic hydroxycarboxylic acid has an asymmetric carbon, it may be an L-form, a D-form, or a mixture thereof, that is, a racemic form.

[Aliphatic polycarboxylic acid and its anhydride]
Specific examples of the aliphatic polycarboxylic acid constituting the polylactic acid-based resin in the present invention include, for example, oxalic acid, succinic acid, malonic acid, glutaric acid, adipic acid, pimelic acid,
Examples thereof include aliphatic dicarboxylic acids such as suberic acid, azelaic acid, sebacic acid, undecandioic acid, dodecandioic acid, and anhydrides thereof. These may be one kind or a mixture of two or more kinds.

[Aliphatic polyhydric alcohol] Specific examples of the aliphatic polyhydric alcohol constituting the polylactic acid resin in the present invention include, for example, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, , 3-butanediol, l, 4-butanediol, 3-methyl-1,5-
Pentanediol, 1,6-hexanediol, 1,9
-Nonanediol, neopentyl glycol, tetramethylene glycol, 1,4-cyclohexanedimethanol and the like. These may be one kind or a mixture of two or more kinds.

[Polysaccharides] Specific examples of polysaccharides include, for example, cellulose, cellulose nitrate, cellulose acetate, methylcellulose, ethylcellulose, celluloid, viscose rayon, regenerated cellulose, cellophane, cupra, cuprammonium rayon, cuprophan, bemberg , Hemicellulose, starch, amylopectin, dextrin, dextran, glycogen, pectin, chitin, chitosan, gum arabic, guar gum, locust bean gum, acacia gum, and the like, and derivatives thereof, with acetyl cellulose and ethyl cellulose being particularly preferred. Used for These may be one kind or a mixture of two or more kinds.

[Molecular weight of polylactic acid-based resin] The molecular weight of the polylactic acid-based resin used in the present invention depends on the intended use, for example, when formed into a molded article such as a packaging material and a container.
The molecular weight is not particularly limited as long as it exhibits substantially sufficient mechanical properties. The molecular weight of the polylactic acid-based resin is generally 1 to 500 as a weight average molecular weight.
And preferably 3 to 3,000,000, more preferably 5 to 20
100,000 is more preferable, 70-100,000 is still more preferable,
9 to 500,000 are most preferred. In general, when the weight average molecular weight is smaller than 10,000, mechanical properties are not sufficient. On the contrary, when the molecular weight is larger than 5,000,000, handling may be difficult or uneconomical. The weight average molecular weight and molecular weight distribution of the polylactic acid-based resin used in the present invention, the production method, the type of solvent,
It can be controlled to a desired one by appropriately selecting reaction conditions such as the type and amount of the catalyst, the reaction temperature, the reaction time, the method of embedding the solvent distilled by azeotropic distillation, and the degree of dehydration of the solvent in the reaction system. it can.

[Method for producing polylactic acid-based resin] The method for producing the polylactic acid-based resin of the present invention is not particularly limited. For example, as a specific example of a method for producing polylactic acid and a polylactic acid-based resin having lactic acid as a structural unit, see JP-A-6-65360.
Reference is made to the method disclosed in the above-mentioned publication, for example, a method as shown in Production Example 2 described below. That is, it is a direct dehydration condensation method in which lactic acid and / or a hydroxycarboxylic acid other than lactic acid, or an aliphatic diol and an aliphatic dicarboxylic acid are directly dehydrated and condensed in the presence of an organic solvent and a catalyst.
As another reference example of the method for producing a polylactic acid-based resin having lactic acid as a structural unit, for example, the following production examples 3 to 6 referred to the method disclosed in JP-A-7-173266.
The method shown in FIG. That is, this is a method in which a homopolymer of at least two kinds of polylactic acid-based resins is copolymerized and transesterified in the presence of a polymerization catalyst. As another specific example of the method for producing polylactic acid, for example, a method as shown in Production Example 1 described below with reference to the method disclosed in US Pat. No. 2,703,316 is exemplified. That is, it is an indirect polymerization method in which lactic acid and / or a hydroxycarboxylic acid other than lactic acid is once dehydrated into a cyclic dimer, and then subjected to ring-opening polymerization.

[Clarifying agent] The clarifying agent used in the present invention is a fatty acid ester represented by the general formula (1) [Formula 5].

[0030]

Embedded image (In the general formula (1), R ¹ and R ^{2 each} have 1 to 1 carbon atoms.
It is a saturated or unsaturated hydrocarbon, linear or branched hydrocarbon group of 30 and n is an integer of 1-4. Examples of the fatty acid esters in the method of the present invention include dimethyl adipate, di-2-ethylhexyl adipate, diisobutyl adipate, dibutyl adipate, diisodecyl adipate, dibutyl diglycol adipate, di-2-ethylhexyl adipate, dibutyl sebacate, and dibutyl sebacate. -2-ethylhexyl sebacate and the like. Particularly, diisodecyl adipate is preferred.

[Amount of Clarifying Agent] The amount of the clarifying agent added to the polylactic acid-based resin is 1 to the polylactic acid-based resin composition.
-6% by weight, preferably 1.5% by weight.
To 5.5% by weight, more preferably 2.0 to 5.0% by weight. When the amount is less than 1% by weight, the effect as a clarifying agent may be insufficient. On the other hand, when the amount is more than 6% by weight, not only the effect as a clarifying agent is not obtained, but also the crystallization becomes transparent. In some cases, appearance and physical properties (rigidity) may change, such as deterioration of properties.

[Inorganic Additive] As long as the transparency of the molded article is not impaired,
In order to improve various physical properties such as an improvement in crystallization speed, an improvement in heat resistance, an improvement in mechanical properties, and an improvement in blocking resistance, an inorganic additive may be added. Specific examples of the inorganic additive include, for example, talc, kaolinite, SiO ₂ , and clay, but it is necessary to appropriately select conditions (addition amount, particle size) so as not to impair the transparency of the molded article. There is. In order to maintain the transparency of the molded article, it is generally recommended to select a particle size substantially smaller than the wavelength of visible light.

More specifically, for the purpose of improving the properties of blocking resistance, for example, SiO ₂ having a particle size of 1 to 50 nm is preferably used without impairing the transparency. In the production method of the present invention, when the aim is to further improve the crystallization rate during molding such as crystallization in a mold during molding or crystallization by heat treatment of the formed molded body, the SiO ₂ component Is preferred. Specifically, talc TM-30 (manufactured by Fuji Talc), kaolin JP-100 (manufactured by Tsuchiya Kaolin), NN kaolin clay (manufactured by Tsuchiya Kaolin), Kaolinite ASP-170 (manufactured by Fuji Talc), Kaolin UW (manufactured by Engelhard), talc RF (manufactured by Fuji Talc), and the like. In this case, a material having a small particle size and being well dispersed without being aggregated when melt-kneaded with a resin is suitably used.

[Amount of Inorganic Additive] The amount of the inorganic additive is preferably such that the transparency of the molded article is not extremely impaired.
Suitable is 30% by weight or less, preferably 20% by weight or less, more preferably 10% by weight or less, still more preferably 5% by weight or less, and most preferably 1% by weight or less.

As long as the transparency of the molded article is not impaired, various elastomers (SBR, NBR, SBS type ternary block copolymer thermoplastic elastomer, etc.) and additives may be further added to the molded article produced by the production method of the present invention. Agents (plasticizers, pigments, stabilizers, antistatic agents, UV absorbers, antioxidants,
Flame retardants, release agents, lubricants, dyes, antibacterial agents), fillers (impact-resistant core / shell particles, impact modifiers, etc.) and pigments (metallic pigments, pearl pigments) are used as appropriate according to the purpose and application. can do.

[Molding / Processing Method] <Mixing / Kneading / Kneading> In the present invention, a polylactic acid-based resin and at least one transparentizing agent selected from the group of compounds represented by the general formula (1) [formula 5] are used. The method for producing a polylactic acid-based resin composition by mixing, kneading, and kneading is a known and publicly known kneading technique, for example, mixing each raw material with a Henschel mixer, a ribbon blender, or the like, or further using an extruder or the like. And a method of kneading the molten polymer while injecting it into the melted polymer.

<Molding> A method for producing a molded article having both transparency and crystallinity, which is the object of the present invention, will be described below. The present invention is a method for producing a molded article having both transparency and crystallinity by crystallizing the above-mentioned polylactic acid-based resin composition during or after molding. As the molding method, generally, injection molding, extrusion molding, blow molding,
Examples thereof include ordinary methods such as inflation molding, profile extrusion molding, injection blow molding, vacuum pressure molding, and spinning, but the resin composition shown in the present invention can be applied to any molding method, and is not limited at all. In the present invention, the molded product needs to be crystallized by some method (for example, heat treatment) at the time of molding or after the molding of the polylactic acid-based resin composition. Specific examples thereof include, for example, a method in which a melt of the composition is filled in a mold at the time of molding and crystallized in the mold as it is (hereinafter, referred to as an in-mold crystallization method). A method of heat-treating an amorphous compact (hereinafter referred to as a post-crystallization method) can be given. In the in-mold crystallization method and the post-crystallization method, the optimum temperature conditions for crystallizing the molded product are different.

Temperature Conditions for Crystallization in In-Mold Crystallization In the case of in-mould crystallization, the set temperature condition of the mold is determined from the crystallization start temperature at the time of temperature decrease in the differential scanning calorimetry of the composition. The temperature range up to the crystallization end temperature is preferable, and the temperature near the top of the crystallization peak is more preferable. At a temperature higher than the crystallization start temperature, the crystallization rate becomes extremely low, the productivity and the operability are deteriorated, and further, the crystallization does not occur, and the desired molded product may not be obtained,
Conversely, if the temperature is lower than the crystallization end temperature, the crystallization rate is extremely low, and the desired molded product may not be obtained.
In this method, the holding time in the mold varies depending on the composition, but is not particularly limited as long as it is equal to or longer than the time required for the molded article to sufficiently crystallize in the mold.

Temperature conditions for crystallization in the post-crystallization method On the other hand, in the case of the post-crystallization method, the set temperature conditions of the mold include a temperature range from the glass transition temperature (Tg) to the melting point (Tm) of the composition, More preferably, (Tg + 5 ° C.) to (Tm−
20 ° C.), more preferably from (Tg + 10 ° C.) to (Tg
m-30 ° C) most preferably from (Tg + 15 ° C) to (Tg
m-40 ° C). When the set temperature is higher than Tm, transparency may be impaired even if crystallization is performed in a short time, or the shape may be distorted. Conversely, if the temperature is lower than Tg, the crystallization speed is extremely low, and the desired crystalline molded product may not be obtained. In this method, the time for heat-treating the molded article varies depending on the composition, but is not particularly limited as long as the molded article is sufficiently long enough to be crystallized.

<Embodiment of Method for Producing a Molded Body Having Both Transparency and Crystallinity> The following is a description of a molding method for a molded body according to the present invention, which can simultaneously impart transparency and crystallinity to a molded body. An embodiment will be described.

Injection Molding (In-Mold Crystallization Method) In the injection molding (in-mold crystallization method), for example, pellets of a composition obtained by adding a clarifying agent to the polylactic acid obtained in Production Example 2 described below. Is filled in a mold held in a temperature range from the crystallization start temperature to the crystallization end temperature, and held, thereby forming a molded article having both transparency and crystallinity intended in the present invention. Can be molded.

Injection molding (post-crystallization method) In the injection molding (post-crystallization method), for example, an amorphous molded article obtained by molding at a mold temperature of 20 ° C. using the above-mentioned pellets From Tg (58 ° C.) to Tm (16
By maintaining the composition in an atmosphere within a temperature range of 5 ° C.) or by bringing it into contact with an appropriate heat medium, an injection-molded article having both transparency and crystallinity intended in the present invention can be formed.

Extrusion molding (post-crystallization method) In the extrusion molding (post-crystallization method), for example, an amorphous film or sheet obtained by molding the above-mentioned pellet by a general T-die extruder is used. , Tg (58 ° C) to T
m (165 ° C.), and continuously passed through an oven (heating furnace) or hot water maintained within a range of m (165 ° C.) to perform heat treatment, or batch heat treatment to obtain the transparency desired in the present invention. A sheet or film having both crystallinity and crystallinity can be formed.

In the blow molding (post-crystallization method), in the blow molding (post-crystallization method), the pellets shown above are melted by a general blow molding machine and filled in a mold to form an amorphous material. After obtaining the preform, heating the obtained preform in an oven (heating furnace),
It is placed in a mold maintained in the range of Tg (58 ° C.) to Tm (165 ° C.), and is blown by sending out pressurized air to have both the transparency and the crystallinity intended in the present invention. Blow bottles can be molded. Here, as the pressurized air, a high temperature [for example, T from room temperature (25 ° C.) or more
When m (temperature of 165 ° C. or lower) is used, the time required for crystallization of the molded body can be reduced.

Vacuum forming / vacuum pressure forming (crystallizing method in a mold) An amorphous film formed by the same method as described above is converted from a crystallization start temperature to a crystallization end temperature by a general vacuum forming machine. By performing vacuum molding or vacuum pressure molding in a mold held within the range, a molded article having both transparency and crystallinity intended in the present invention can be molded. Here, high pressure [for example, room temperature (2
When a material having a temperature of 5 ° C. or more and Tm (a temperature of 165 ° C. or less) is used, the time required for crystallization of the molded body can be reduced.

Vacuum Forming / Vacuum Pressure Forming (Vacuum Forming of a Crystalline Film) A crystalline film formed by the same method as described above is subjected to vacuum pressure forming to obtain the transparency and crystallinity intended in the present invention. It is possible to mold a molded article having the same. The polylactic acid-based resin molded article of the present invention obtained by molding by the above-described molding method has both crystallinity and transparency, and has high heat resistance.

In the present invention, the fact that the polylactic acid-based resin molded article has transparency means that when a molded article having a thickness of 1 mm is overlaid on a newspaper, characters of the newspaper can be recognized through the molded article. And the haze of the molded article having a thickness of 1 mm is 30% or less. In the present invention, that the polylactic acid-based resin molded article has heat resistance means that the crystallinity measured by an X-ray diffraction method is 10% or more. That is, the heat resistance means that the Vicat softening point (Vicat softening temperature) is 100 to 160 ° C. in the Vicat softening point (Vicat softening temperature) measurement (ASTM D1525).
Means that According to the production method of the present invention, a polylactic acid-based resin molded article having both crystallinity (heat resistance) and transparency having a crystallinity of 10% or more and a haze of 30% or less at a thickness of 1 mm is obtained. According to the production method of the present invention, even when the crystallinity is 30% or more, the haze is 30% or less, 20% or less, 15% or less at a thickness of 1 mm.
Further, a polylactic acid-based resin molded article having both crystallinity (heat resistance) of 10% or less and transparency is obtained.

The polylactic acid-based resin molded product having transparency, crystallinity (heat resistance) and decomposability of the present invention can be prepared by injection molding, film, bag, tube, or the like obtained by a known and publicly used molding method.
It includes sheets, cups, bottles, trays, yarns, etc., and there is no restriction on the shape, size, thickness, design, etc.
Specifically, the molded article of the present invention is a food packaging bag, tableware and forks, spoons, bottles for dairy products, soft drinks and alcoholic beverages, food containers such as wrap films, trays,
Daily miscellaneous goods such as bottles and films, cosmetic containers, garbage bags, caps, (adhesive) tapes, air mats, containers for bleach, bottles for liquid detergents, leisure goods such as tents and waterproof sheets, medical equipment Containers and packaging materials for medical materials and pharmaceuticals, fishing lines, fish nets, containers and packaging materials and capsules for agricultural supplies, containers and packaging materials and capsules for fertilizers, containers and packaging materials and capsules for seedlings, agriculture and horticulture Film, product packaging film, overhead project film, heat ray reflective film, liquid crystal display film and the like.

In addition, the film or sheet obtained by the method of the present invention may be laminated with a sheet of another material such as paper or another polymer by laminating or laminating with an adhesive or heat fusion, etc. It can also be a body. In particular, conventionally, an amorphous film of a polylactic acid-based resin having excellent transparency such as a copolymer having polylactic acid or a polylactic acid block and a polybutylene succinate block, for example,
When heat lamination is performed on paper or the like, there has been a problem that heat is generated during lamination, which causes crystallization and opacity. Therefore, in applications where transparency is required, heat treatment conditions during thermal lamination are limited, or a lamination method using an adhesive is preferably used.Moreover, in applications where transparency and heat resistance are required, The resin composition could not be used. However, when those resin compositions containing the clarifying agent of the present invention are used, for example, a transparent amorphous film is directly heat-laminated on paper or the like, bonded to paper or the like, and crystallized from the composition. May be performed simultaneously. Further, the laminated body once subjected to thermal lamination may be further heat-treated to be crystallized.
Under any conditions, maintain its transparency, and furthermore,
A laminate having heat resistance can be obtained.

[0050]

[Examples] Production examples, examples and comparative examples are shown below.
The present invention will be described in detail. Note that descriptions of synthesis examples, examples, comparative examples, aspects and the like in the specification of the present application are descriptions for assisting understanding of the contents of the present invention, and the description narrows the technical scope of the present invention. It is not of a nature to be interpreted.

A. Production Examples Production methods of polylactic acid-based resins used in Examples and Comparative Examples are described below. All parts in the text are based on weight. The average molecular weight (weight average molecular weight Mw) of the polymer was measured by gel permeation chromatography using polystyrene as a standard under the following conditions. Apparatus: Shimadzu LC-IOAD Detector: Shimadzu RID-6A Column: Hitachi Chemical GL-S350DT-5, GL-
S370DT-5 Solvent: chloroform Concentration: 1% Injection amount: 20 μl [Production Example 1] <Production of polymer A (poly L-lactide)> 100 parts by weight of L-latatide and stannous octoate 0.1%
01 parts and 0.03 parts of lauryl alcohol were sealed in a thick cylindrical stainless steel polymerization vessel equipped with a stirrer, degassed under vacuum for 2 hours, and then replaced with nitrogen gas. The mixture was heated at 200 ° C. for 3 hours with stirring under a nitrogen atmosphere. While maintaining the temperature as it was, the air was gradually degassed by a vacuum pump through an exhaust pipe and a glass receiver, and the pressure inside the reaction vessel was reduced to 3 mmHg. One hour after the start of degassing, the distillation of monomers and low-molecular-weight volatiles disappeared, so the inside of the vessel was replaced with nitrogen, the polymer was drawn out from the lower part of the vessel in the form of a strand, pelletized, and homopolymer of L-lactide (polymer A) was obtained. The yield was 78% and the weight average molecular weight Mw was 136,000.

[Production Example 2] <Production of polymer B (poly-L-lactic acid)> 10 kg of 90% L-lactic acid was placed at 150 ° C / 5 in a 100-liter reactor equipped with a Dien-Stark trap.
After distilling water while stirring at 0 mmHg for 3 hours, 6.2 g of tin powder was added, and the mixture was further heated at 150 ° C / 30 mmHg for 2 hours.
The mixture was oligomerized by stirring for an hour. 28.8 g of tin powder and 21.1 kg of diphenyl ether were added to this oligomer,
An azeotropic dehydration reaction at 150 ° C./35 mmHg was performed, and the distilled water and the solvent were separated by a water separator, and only the solvent was returned to the reactor. After 2 hours, the organic solvent to be returned to the reactor was passed through a column packed with 46 kg of molecular sieve 3A, and then returned to the reactor. The reaction was carried out at 150 ° C./35 mmHg for 40 hours, and the weight average molecular weight was 146,000. A solution of polylactic acid was obtained. Diphenyl ether 44 dehydrated in this solution
After addition of kg, the mixture was diluted and cooled to 40 ° C., and the precipitated crystals were filtered, washed three times with 10 kg of n-hexane, and dried at 60 ° C./50 mmHg. 0.5 N of this powder
-Add 12 kg of HCl and 12 kg of ethanol at 35 ° C
After stirring for 1 hour, the mixture was filtered and dried at 60 ° C./50 mmHg. 1 kg (85% yield)
I got The weight average molecular weight Mw of this polylactic acid (Polymer B) was 145,000.

[Production Example 3] <Production of copolymer C (polybutylene succinate / polylactic acid copolymer)> 50.5 g of 1,4-butanediol and 66.5 succinic acid
g to 293.0 g) Metal tin 2.02
g was added and heated and stirred at 130 ° C./140 mmHg for 7 hours while distilling water out of the system to oligomerize. to this,
Attach Dean-Stark trap, 140 ° C
After azeotropic dehydration for 8 hours at / 30 mmHg, a tube filled with 40 g of molecular sieve 3A was attached, and the distilled solvent was returned to the reactor through the molecular sieve tube, and stirred at 130 ° C / 17 mmHg for 49 hours. did. The reaction mass was dissolved in 600 ml of chloroform, added to 4 liters of acetone and reprecipitated, and then a solution of HCl in isopropyl alcohol (hereinafter abbreviated as IPA) (H
(Cl concentration 0.7 wt%) for 0.5 hour (three times), washed with IPA, and dried under reduced pressure at 60 ° C. for 6 hours to obtain polybutylene succinate (hereinafter abbreviated as PSB). The weight average molecular weight Mw of this polymer is 1
It was 18,000. To 80.0 g of the obtained polybutylene succinate, 0.7 g of metal tin was mixed with 120.0 g of polylactic acid (weight average molecular weight Mw is 2,000,000) and 800 g of diphenyl ether obtained in the same manner as in Production Example 2. And
The dehydration condensation reaction was performed again at 130 ° C./17 mmHg for 20 hours. After the reaction, post-treatment was performed in the same manner as in Production Example 2,
Copolymer of polybutylene succinate and polylactic acid 1
88 g (94% yield) were obtained. The weight average molecular weight Mw of this copolymer of polybutylene succinate and polylactic acid (copolymer C) was 14,000.

[Production Example 4] <Production of copolymer D (polybutylene succinate / polylactic acid copolymer)> 40.0 g of polybutylene succinate (weight average molecular weight Mw is 118,000), 160.0 g of polylactic acid (Weight average molecular weight Mw was 50000), except that a copolymer of polybutylene succinate and polylactic acid (copolymer D) was obtained. The yield is 9
6%, and the weight average molecular weight Mw was 136,000.

[Production Example 5] <Production of copolymer E (polybutylene succinate / polylactic acid copolymer)> 20.0 g of polybutylene succinate (weight average molecular weight Mw is 118,000), 180.0 g of polylactic acid Except for using (weight average molecular weight Mw of 100,000), the same procedure as in Production Example 3 was carried out to obtain a copolymer of polybutylene succinate and polylactic acid (copolymer E). The yield was 94% and the weight average molecular weight Mw was 142,000.

[Production Example 6] <Production of copolymer F (polycaproic acid / polylactic acid copolymer)> A reaction was carried out in the same manner as in Production Example 2 except that 6-hydroxycaproic acid was used instead of lactic acid. As a result, polycaproic acid (weight average molecular weight Mw was 150,000) was obtained. Next, 20.0 g of the obtained polycaproic acid and 18 of polylactic acid were obtained.
Using 0.0 g (weight average molecular weight Mw is 100,000) and in the same manner as in Production Example 4, a copolymer (copolymer F) of polycaproic acid and polylactic acid was obtained. The yield is 92%,
The weight average molecular weight Mw was 153,000.

B. Evaluation method [Evaluation of physical properties] The conditions for evaluating the physical properties of the molded articles produced using the polylactic acid-based resin compositions obtained in Production Examples 1 to 6 are as follows. Transparency (Haze) According to JIS K-6714, Tokyo Denshoku Haze M
The measurement was carried out using an eter.

Crystallinity A test piece after molding was measured using an X-ray diffractometer (Rint 1500, manufactured by Rigaku Corporation), and the ratio of the crystal peak area to the total area of the obtained chart was determined. Heat resistance [Vicat softening temperature (ASTM-D152
5)] A test piece after molding was measured under a load of 1 kgf.

Crystallization start temperature, crystallization end temperature Differential scanning calorimeter (manufactured by Shimadzu Corporation, DSC-50)
The temperature at which the crystallization peak was observed when the temperature was lowered at 10 ° C./min after the molded body was once melted was defined as the crystallization start temperature, and the temperature at which the crystallization peak was no longer recognized as the crystallization end temperature. And

Glass transition temperature (Tg), melting point (T
m) Differential scanning calorimeter (manufactured by Shimadzu Corporation, DSC-50)
The point at which the molded body changed to a rubbery state when the temperature of the molded body was raised at 10 ° C./min was defined as the glass transition point (Tg), and the peak of the melting peak was defined as the melting point (Tm).

C. Examples and Comparative Examples In the following examples, when the molded body is subjected to heat treatment,
If the crystallization in the mold is performed at the time of cooling, the temperature should be set within the range from the crystallization start temperature at the time of cooling to the crystallization end temperature or more, and after the molding, the crystallization is performed at the time of the temperature increase by the heat treatment operation. If so, the temperature was set within the temperature range from the glass transition temperature to the melting point.

Example 1 [Injection molding] 95 parts by weight of the polylactic acid obtained in Production Example 2 and 5 parts by weight of diisodecyl adipate as a clarifying agent were thoroughly mixed with a Henschel mixer, and the cylinder temperature of the extruder was set to 170. The pellet was formed under the condition of ~ 210 ° C. The pellets are made by Japan Steel Works J
SW-75 injection molding machine, cylinder set temperature 180-2
Melted under the condition of 00 ° C., filled in a mold at a set temperature of 30 ° C., and cooled for 30 seconds. A 0 mm thick transparent flat plate was obtained. The transparency (haze) of this flat plate is 2
%, Crystallinity was 0%, and Vicat softening point was 58 ° C. This flat plate was heat-treated in a dryer at 120 ° C./5 min. The transparency (haze) of the obtained flat plate was 6%, the crystallinity was 40%, and the Vicat softening point was 150 ° C. The results are shown in Table 1 [Table 1].

[Examples 1-2 to 1-6 [Injection molding]] The same as Example 1-1 except that the amounts of the polymer and the clarifying agent were changed as shown in Table 1 [Table 1]. The transparency (haze), crystallinity, and Vicat softening point of each obtained flat plate were measured. The results are shown in Table 1 [Table 1].

[Comparative Examples 1-1 to 1-6 [Injection Molding]] The same procedure as in Example 1 was carried out except that diisodecyl adipate as a clarifying agent was omitted. The transparency (haze), crystallinity, and Vicat softening point of each obtained flat plate were measured.
The results are shown in Table 2 [Table 2].

Example 2-1 [Blow molding] The polylactic acid obtained in Production Example 2 as a polymer and 5% by weight of diisodecyl adipate as a clarifying agent were sufficiently mixed with a Henschel mixer, and the extruder cylinder temperature was set. 170 ~
Pellets were formed at 210 ° C. The pellets are melted under an injection blow molding machine (manufactured by Nissei ASB Machine Co., ASB-50) at a cylinder set temperature of 180 to 200 ° C.,
Filling the mold (A) at the set temperature of 20 ° C, cooling time is 30
Seconds, a preformed body (bottomed parison) having a thickness of 2.0 mm was obtained. The obtained parison is heated in a heating furnace to a parison temperature of 1
A mold heated to 20 ° C. and kept at 120 ° C.
(B), and under the condition of a pressure of pressurized air of 4 kgf / cm ² , the vertical magnification was doubled and the horizontal magnification was doubled, and the internal volume was 500 m.
1 container was obtained. The transparency (haze) of the obtained container (thickness: 0.5 mm) was 3% (7% in terms of 1 mm thick haze), the crystallinity was 43%, and the Vicat softening point was 150 ° C.
Met.

Comparative Example 2-1 [Blow Molding] Example 4 was repeated except that the clarifying agent (diisodecyl adipate) was omitted.
Was performed in the same manner as described above. The resulting container (0.5 m thick)
m) had a transparency (haze) of 75% (80% in terms of a 1 mm thick haze), a crystallinity of 45%, and a Vicat softening point of 150 ° C.

Comparative Example 2-2 [Blow Molding] A parison temperature was set to 55 ° C. and a mold (B) temperature was set to 30 ° C.
It carried out by the method similar to Example 4-1. The transparency (haze) of the obtained container (thickness 0.5 mm) was 1.3% (lmm).
The thickness was 3% in terms of haze value), the crystallinity was 0%, and the Vicat softening point was 59 ° C.

Example 3-1 [Extrusion molding] The polylactic acid carried in Production Example 1 as a polymer and 5% by weight of diisodecyl adipate as a clarifying agent were sufficiently mixed with a Henschel mixer, and then the extruder cylinder temperature was set. 170-2
Pellets were formed at 10 ° C. The pellets are extruded from a T-die 50 mmΦ extruder (Frontier, die width 400 m).
m) Melting was performed under the condition of a cylinder set temperature of 180 to 200 ° C, and a transparent 0.5 mm thick sheet was obtained at a die temperature of 185 ° C. The transparency (haze) of this sheet (thickness: 0.5 mm) is 1% (converted to a haze value of 1 mm thickness).
%) And the crystallinity was 0%. Further, the sheet was continuously passed through a hot-air dryer (temperature: 100 ° C., residence time: 2 min) and heat-treated. The transparency of the obtained sheet was 3% (8% in terms of 1 mm thick haze), and the crystallinity was 40%.

Comparative Example 3-1 [Extrusion molding] The same procedure as in Example 5-1 was carried out except that diisodecyl adipate as a clarifying agent was omitted. Transparency (haze) of the obtained sheet
Was 73% (84% in terms of 1 mm thick haze), and the crystallinity was 39%.

Comparative Example 3-2 [Extrusion Molding]
The haze value of the sheet (thickness 0.5 mm) obtained in 1 was 1
%, Crystallinity is 0%) in a hot air dryer at 55 ° C.
Heat treatment was performed for 0 min. The resulting sheet (0.5 m thick)
m) had a transparency (haze) of 1% (2% in terms of a 1 mm thick haze) and a crystallinity of 0%.

Example 4-1 [Inflation molding] Using the polymer obtained in Production Example 4 (copolymer of polybutylene succinate and polylactic acid), 5 parts by weight of diisodecyl adipate as a clarifying agent was added to Henschel After sufficiently mixing with a mixer, the mixture was pelletized under the conditions of an extruder cylinder set temperature of 170 to 210 ° C. The bellet was blown with an inflation molding machine (Kawada Seisakusho, 45 mm
Φ) Melted under the condition of a cylinder set temperature of 165 to 180 ° C. to obtain an inflation film having a die temperature of 170 ° C., an expansion ratio (BUR) of 2.5, a folded diameter of 250 mm and a thickness of 0.05 mm. The transparency (haze) of this film was 0.5% (3% in terms of 1 mm thick haze), and the crystallinity was 0%. Further, the obtained film was heat-treated in warm water (temperature: 85 ° C., residence time: 2 min). The transparency (haze) of this film (thickness: 0.05 mm) was 0.7% (5% in terms of 1 mm thick haze), and the crystallinity was 35%.

[Comparative Example 4-1 [Inflation molding]] The same procedure as in Example 4-1 was carried out except that the clarifying agent (diisodecyl adipate) was omitted. The transparency (haze) of the obtained sheet (thickness 0.5 mm) was 43% (lm).
70% when converted to a m-thick haze), with a crystallinity of 34%
Met.

[Example 5-1 [Extruded Molding]] The polylactic acid obtained in Production Example 2 as a polymer and 5% by weight of diisodecyl adipate as a clarifying agent were sufficiently mixed with a Henschel mixer, and then set in an extruder cylinder. Temperature 170
It was pelletized under the condition of ~ 210 ° C. The pellets are melted under a condition of a cylinder setting temperature of 180 to 200 ° C., extruded at a die temperature of 175 ° C., and a sizing box equipped with a vacuum device (cooling temperature of 30 mm). ℃)
A hollow molded body having a thickness of 0.5 mm and an outer dimension of 40 mm × 30 mm was obtained. The transparency (haze) of this hollow body is 1.5%
(2% in terms of 1 mm thick haze), and the crystallinity is 0
%Met. Furthermore, the hollow body is heated with a hot air drier (temperature 100
C) and a heat treatment was carried out by continuously passing the mixture for a residence time of 2 min) to obtain a hollow body. Obtained hollow body (thickness 0.5 mm)
Had a transparency (haze) of 3.5% (8% in terms of a 1 mm thick haze) and a crystallinity of 41%.

[Comparative Example 5-1 [Extruded Molding]] The same procedure as in Example 8 was carried out except that the clarifying agent (diisodecyl adipate) was omitted. The obtained sheet (thickness 0.5 mm)
Had a transparency (haze) of 71% (77% in terms of a 1 mm thick haze) and a crystallinity of 40%.

Example 6-1 [Vacuum / Compressed Air Forming-1; Forming of Crystallized Sheet] The polylactic acid obtained in Production Example 2 as a polymer, and 5% by weight of diisodecyl adipate as a clarifying agent were mixed with a Henschel mixer. After mixing well with
The extruder was pelletized under the conditions of a cylinder set temperature of 170 to 210 ° C. The bellet was melted at a T-die 50 mmφ extruder (manufactured by Frontier, die width 400 mm) at a cylinder set temperature of 180 to 200 ° C.
A sheet having a thickness of 0.25 mm was obtained at 5 ° C. The transparency (haze) of this sheet (0.25 mm thickness) is 1.0%.
(2% in terms of 1 mm thick haze), and the crystallinity is 0
%Met. Further, the sheet is heated with a hot air drier (temperature 1).
(00 ° C.) and a heat treatment was performed by continuously passing the solution for 2 minutes. The transparency (haze) of the obtained sheet (having a thickness of 0.25 mm) was 2.5% (7% in terms of 1 mm thick haze), and the crystallinity was 38%.

Next, the sheet was prepared with a long diameter of 146 mm and a short diameter.
Vacuum equipped with an elliptical mold having a diameter of 100 mm and a depth of 30 mm
Using a compressed air molding machine, heating temperature 120 ° C, holding time 30
The elliptical mold softened in seconds and set at a mold temperature of 60 ° C
4kgf / cm compressed air pressure ^TwoAnd vacuum adhesion for 10 seconds
(Decompression degree: 50 mmHg) to obtain a molded body. Molded
Transparency (haze) is 3% (converted to 1 mm thick haze)
And 8%), and the crystallinity was 40%.

Example 6-2 [Vacuum / Compressed Air Forming-2; Crystallizing an Amorphous Sheet in a Mold] The sheet having a thickness of 0.25 mm obtained in Example 6-1 (having a haze value of 0%, The crystallinity is 0%), and a vacuum pressure air molding machine equipped with an elliptical mold having a major axis of 146 mm, a minor axis of 100 mm and a depth of 30 mm is used. A compressed air pressure of 1 is applied to the elliptical mold with the mold temperature set to 100 ° C.
kgf / cm ² for 1 minute under vacuum (pressure reduction 50 mmH
g) to obtain a molded body. The transparency (haze) of the molded article was 3% (8% in terms of a 1 mm thick haze), and the crystallinity was 41%.

Comparative Example 6-1 A procedure was performed in the same manner as in Example 6-2 except that the clarifying agent (diisodecyl adipate) was omitted. The transparency (haze) of the obtained molded product is 73.
% (82% in terms of a haze having a thickness of 1 mm), and the crystallinity was 42%.

[Comparative Example 6-2] The same procedure as in Example 6-2 was carried out except that the mold temperature was 55 ° C. The transparency (haze) of the obtained molded product (having a thickness of 0.25 mm) is 1%.
(2% in terms of 1 mm thick haze), and the crystallinity is 0
%Met.

[0080]

[Table 1]

[0081]

[Table 2]

[0082]

According to the present invention, a polylactic acid-based resin molded article having both transparency and crystallinity (heat resistance) can be provided.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hisashi Aihara 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Prefecture Inside (72) Inventor Yasuhiro Kitahara 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Mitsui Chemicals Inc. 72) Inventor Kazuhiko Suzuki 1190 Kasama-cho, Sakae-ku, Yokohama City, Kanagawa Prefecture (72) Inventor Masanobu Ajioka 1190 Kasama-cho, Sakae-ku, Yokohama City, Kanagawa Prefecture Mitsui Chemicals Corporation

Claims (13)

[Claims] 1. A polylactic acid-based resin (A) having the general formula (1)
A polylactic acid-based resin molded article containing at least one transparentizing agent (B) selected from the group of compounds represented by Chemical Formula 1, wherein the polylactic acid-based resin (A) and the transparentizing agent ( 94-99% by weight of the polylactic acid-based resin (A) based on the total weight of B) and the clarifying agent (B)
A polylactic acid-based resin molded product containing 6 to 1% by weight of a polylactic acid and having both transparency and heat resistance. Embedded image (In the general formula (1), R ¹ and R ^{2 each} have 1 to 1 carbon atoms.
It is a saturated or unsaturated hydrocarbon, linear or branched hydrocarbon group of 30 and n is an integer of 1-4. ) 2. The polylactic acid-based resin is at least one selected from the group consisting of polylactic acid, a copolymer having a polylactic acid block and a polybutylene succinate block, and a copolymer having a polylactic acid block and a polycaproic acid block. The polylactic acid-based resin molded product according to claim 1, which is: 3. A method according to claim 1, wherein at least one clarifying agent (B) selected from the group of compounds represented by the general formula (1):
The polylactic acid-based resin molded product according to claim 1 or 2, which is diisodecyl adipate. 4. Transparency: 1% thick haze value of 30%
The polylactic acid-based resin molded product according to any one of claims 1 to 3, which is equivalent to the following. 5. A heat resistance, a Vicat softening point of 100 to 100.
The polylactic acid resin molded article according to any one of claims 1 to 4, which corresponds to a temperature of 160 ° C. 6. A polylactic acid-based resin (A) having the general formula (1)
A method for producing a polylactic acid-based resin molded product containing at least one transparentizing agent (B) selected from the group of compounds represented by Chemical Formula 2, wherein the polylactic acid-based resin (A) and the transparent Polylactic acid-based resin composition containing 94 to 99% by weight of the polylactic acid-based resin (A) and 6 to 1% by weight of the clarifying agent (B) based on the total weight of the agent (B) A method for producing a polylactic acid-based resin molded article having both transparency and heat resistance, wherein a heat treatment is performed at the time of molding or after molding. Embedded image (In the general formula (1), R ¹ and R ^{2 each} have 1 to 1 carbon atoms.
It is a saturated or unsaturated hydrocarbon, linear or branched hydrocarbon group of 30 and n is an integer of 1-4. ) 7. A heat treatment method comprising: once melting a polylactic acid-based resin composition, filling the polylactic acid-based resin composition in a mold kept at a temperature ranging from a crystallization start temperature to a crystallization end temperature. 7. The method according to claim 6, wherein the crystallization is performed. 8. A heat treatment method comprising: cooling and solidifying a melt of a polylactic acid-based resin composition in a mold to obtain an amorphous molded body; The method according to claim 6, wherein the crystallization is performed in a temperature range from a glass transition temperature to a melting point. 9. The polylactic acid-based resin is at least one selected from the group consisting of polylactic acid, a copolymer having a polylactic acid block and a polybutylene succinate block, and a copolymer having a polylactic acid block and a polycaproic acid block. The method according to claim 6, wherein: 10. A transparentizing agent (B) selected from the group consisting of compounds represented by the general formula (1):
Is diisodecyl adipate. The method according to claim 6, wherein 11. The transparency is 1 mm thick and the haze value is 30.
%. The method according to claim 6, which is equivalent to being equal to or less than 10%. 12. The heat resistance and the Vicat softening point are 100
The method according to any one of claims 6 to 11, which corresponds to a temperature of up to 160 ° C. 13. A polylactic acid-based resin molded article having both transparency and heat resistance, obtained by the production method according to claim 6. Description: