JP5332552B2 - Chip-like product made of polylactic acid resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a chip-formed material consisting of a composition containing mainly of a polylactic acid-based resin having a good molding processability, showing a good roll release of film on forming time, not blocking the film produced by film formation and also having a good flexibility and transparency. <P>SOLUTION: This chip-formed material consists of a composition containing (A) &ge;24 and &le;64 wt.% polylactic acid-based resin, (B) &ge;10 and &le;50 wt.% aliphatic polyester other than the polylactic acid-based resin (A) and/or an aliphatic aromatic polyester, (C) &ge;5 and &le;30 wt.% plasticizer and (D) &ge;0.1 and &le;5 wt.% organic lubricant, and shows &ge;0.1 and &le;15 g/10 min melt mass flow rate. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a chip-like product composed of a polylactic acid resin composition mainly composed of a polylactic acid resin softened by a plasticizer. Specifically, it has good molding processability, anti-blocking properties and transparency. The present invention relates to a chip-like product made of a polylactic acid resin composition having good biodegradability.

  Conventionally, plastic waste has been mainly treated by incineration or landfill. However, problems such as generation and discharge of harmful by-products due to incineration, reduction of landfill sites, and environmental pollution due to illegal dumping have become apparent.

  As interest in such plastic waste disposal problems increases, research and development of biodegradable plastics that are decomposed by enzymes and microorganisms are actively conducted. In recent years, aliphatic polyester materials have attracted attention as biodegradable materials, and among these, technological development is particularly advanced for polylactic acid.

  Polylactic acid is a polymer obtained by using starch obtained from corn, potatoes, and the like as a raw material and further chemically synthesizing the produced lactic acid. Polylactic acid has excellent mechanical properties, heat resistance, and transparency among aliphatic polyesters, so research aimed at developing various molded products such as films, sheets, tapes, fibers, ropes, nonwoven fabrics, and containers. Development is actively underway. However, in applications such as wrapping films for food packaging, for example, polylactic acid has insufficient properties such as flexibility as it is, and therefore a technique for imparting necessary properties such as flexibility and anti-blocking properties has been studied. However, at present, the technology related to the chip-like product is not disclosed.

  For example, Patent Document 1 is a patent relating to a polyester film that has flexibility and suppresses volatilization, exudation, and extraction (bleed out) of oligomer components and plasticizers when used as a molded product. Although there is a description of a polylactic acid polymer chip containing a high concentration of a plasticizer in this document, this chip does not contain an effective lubricant, so that there is a problem that it is easily blocked during film formation.

Patent Document 2 discloses a film containing a polylactic acid polymer and another aliphatic polyester in a certain ratio. However, in this technique, the flexibility of the film was insufficient for use as a packaging material.
Patent Document 3 provides applied products such as films, sheets, and molded products using a plasticizer for suppressing bleed-out to the surface of the polylactic acid resin and imparting excellent flexibility. In the examples of this document, polylactic acid and polypropylene glycol polycarbonate compound A are added and melt-mixed using a twin-screw kneading extruder to obtain a mixture chip. However, even if this chip was used, it was difficult to form a film and it was difficult to obtain a film having no defects.

  Further, Patent Document 4 proposes an agricultural polylactic acid film which is formed by forming a resin composition containing a polylactic acid-based resin, a plasticizer, a lubricant and the like into a film shape and does not block the film. Unlike the present invention, the resin composition does not contain an aliphatic polyester or an aliphatic aromatic polyester (B) other than the polylactic acid resin (A). In the examples, the blended composition is directly supplied to an extruder to form a film, and no chips are formed. We tried to make a chip by a twin screw extruder with reference to the conditions of the examples of the blended composition, but because the temperature setting was not appropriate, the discharge was not stable and the uniformity was insufficient, and the chip was dried. As a result, the chips were partially fused together, and a desired chip that did not block was not obtained. The reason for this is that it does not contain an aliphatic polyester or aliphatic aromatic polyester (B) other than the polylactic acid-based resin (A), and the viscosity is reduced by not managing the water content of the blended composition, that is, melt mass flow. It is possible that the rate value was not appropriate.

As described above, in the prior art, the chip-like materials are easily fused with each other, the metal roll roll is not easily separated at the time of forming the film, and the formed film is also blocked, and the flexibility and transparency are also low. It was difficult to obtain a good biodegradable polylactic acid film.
JP-A-2005-105150 JP-A-11-222528 JP 2006-199799 A JP-T-2006-45290

The present invention has been made in order to solve the above-described problems, and has good moldability, and further, the film is easily separated from the roll during molding, and the formed film does not block and is flexible. In addition, the present invention has been made for the purpose of providing a chip-like product comprising a polylactic acid resin composition mainly composed of a polylactic acid resin having good transparency.

The present invention adopts the following means in view of the above-described state of the prior art. That is:
1) A polylactic acid resin composition comprising a polylactic acid resin (A), an aliphatic aromatic polyester (B), a plasticizer (C), and an organic lubricant (D),
In a total of 100% by mass of the polylactic acid resin (A), aliphatic polyester and / or aliphatic aromatic polyester (B), plasticizer (C), and organic lubricant (D), the polylactic acid resin (A) 24 mass% to 64 mass%, aliphatic polyester and / or aliphatic aromatic polyester (B) is 10 mass% to 50 mass%, plasticizer (C) is 5 mass% to 30 mass%, organic lubricant (D) is 0.1 mass% or more and 5 mass% or less,
The melt mass flow rate is 0.1 g / 10 min or more and 15 g / 10 min or less,
A block copolymer in which the plasticizer (C) has a polyether segment and / or a polyester segment and has at least one polylactic acid segment having a number average molecular weight of 1,200 to 10,000 in one molecule. A chip-like product characterized by being a polymer.
2) The polylactic acid resin composition further includes a pigment (E),
In a total of 100% by mass of the polylactic acid resin (A), aliphatic polyester and / or aliphatic aromatic polyester (B), plasticizer (C), organic lubricant (D), and pigment (E), the polylactic acid resin The resin (A) is 24% by mass or more and 64% by mass or less, the aliphatic polyester and / or the aliphatic aromatic polyester (B) is 10% by mass or more and 50% by mass or less, and the plasticizer (C) is 5% by mass or more and 30% by mass. The chip shape as described in 1), wherein the organic lubricant (D) is 0.1% by mass or more and 5% by mass or less, and the pigment (E) is 0.01% by mass or more and 20% by mass or less. object.
3) The chip-like product according to 1) or 2), wherein the aliphatic polyester and / or the aliphatic aromatic polyester (B) is a polybutylene succinate resin.
4) The chip-like product according to any one of 1) to 3), wherein the plasticizer (C) is solid at 20 ° C. ± 5 ° C.
5) The chip-like product according to any one of 1) to 4) above, wherein a crystal melting heat quantity ΔHpl by differential scanning calorimetry is 5 J / g or more and 40 J / g or less.
6) The chip-like product according to any one of 1) to 5), wherein the moisture content is 1000 ppm or less.
7) The chip-like product according to any one of 1) to 6), which is used for an inflation film-forming method.
8) A film formed using the chip-like material according to any one of 1) to 7).

  According to the chip-like product of the present invention, flexibility is imparted by blending the plasticizer, and the chip-like product is fused to each other by the action of the organic lubricant, or at the time of film formation using the chip-like product of the present invention. A biodegradable polylactic acid film having no adhesion to the metal roll, good separation from the roll, no blocking of the film formed, and good flexibility and transparency can be obtained.

  The polylactic acid-based resin (A) used in the present invention is one having L-lactic acid and / or D-lactic acid as a main component and a component derived from lactic acid of 70% by mass or more and 100% by mass or less. Homopolylactic acid composed of lactic acid and / or D-lactic acid is preferably used.

  The polylactic acid resin (A) used in the present invention preferably has crystallinity. The polylactic acid resin has crystallinity when the polylactic acid resin is sufficiently crystallized under heating and then subjected to differential scanning calorimetry (DSC) measurement in an appropriate temperature range. This means that the heat of crystal melting derived from is observed. In general, homopolylactic acid has higher melting point and crystallinity as the optical purity is higher. The melting point and crystallinity of polylactic acid are affected by the molecular weight and the catalyst used during polymerization, but normally, homopolylactic acid having an optical purity of 98% or higher has a melting point of about 170 ° C. and a relatively high crystallinity. In addition, as the optical purity decreases, the melting point and crystallinity decrease. For example, homopolylactic acid having an optical purity of 92% has a melting point of about 150 ° C., and homopolylactic acid having an optical purity lower than 76% is often the case. It has no clear melting point and becomes amorphous.

  The polylactic acid resin (A) used in the present invention can be mixed with crystalline homopolylactic acid and amorphous homopolylactic acid, and the proportion of amorphous homopolylactic acid impairs the effects of the present invention. What is necessary is just to determine within a range. In order to obtain a chip-like product having a heat of crystal fusion ΔHpl of 5 J / g or more and 40 J / g or less, polylactic acid having an optical purity of 90% or more in at least 100% by mass in total of the chip-like product. It is preferable to contain 5 mass% or more. Further, from the viewpoint of suppressing the bleeding of the plasticizer and imparting flexibility when the film is formed, the polylactic acid having an optical purity of 90% or more is 50% by mass or less in the total 100% by mass of the whole chip-like product. preferable.

  In addition, the polylactic acid resin (A) used in the present invention may be a copolymerized polylactic acid obtained by copolymerizing other monomer components having ester forming ability in addition to L-lactic acid and D-lactic acid. Examples of copolymerizable monomer components include glycolic acid, 3-hydroxybutyric acid, 4-hydroxybutyric acid, 4-hydroxyvaleric acid, 6-hydroxycaproic acid, and other hydroxycarboxylic acids, as well as ethylene glycol, propylene glycol, and butane. Compounds containing a plurality of hydroxyl groups in the molecule such as diol, neopentyl glycol, polyethylene glycol, glycerin, pentaerythritol or their derivatives, succinic acid, adipic acid, sebacic acid, fumaric acid, terephthalic acid, isophthalic acid, 2 , 6-naphthalenedicarboxylic acid, 5-sodium sulfoisophthalic acid, 5-tetrabutylphosphonium sulfoisophthalic acid and the like, or compounds containing a plurality of carboxylic acid groups in the molecule. In addition, it is preferable to select the component which has biodegradability among the above-mentioned copolymerization components according to a use.

  The polylactic acid resin (A) used in the present invention includes not only a polymer composed only of lactic acid but also a copolymerized polylactic acid obtained by copolymerizing other monomer components having the ester forming ability as described above. . The weight average molecular weight of the polylactic acid-based resin (A) is not particularly limited, but is preferably about 10,000 to 1,000,000, particularly 30,000 to 50 from the viewpoints of film strength and moldability. About ten thousand is preferable.

  The chip-like product of the present invention has a polylactic acid resin (A), aliphatic polyester and / or aliphatic aromatic polyester (B), plasticizer (C), and organic lubricant (D) in a total of 100% by mass, It consists of a polylactic acid resin composition containing 24% by mass or more and 64% by mass or less of the polylactic acid resin (A). The polylactic acid-based resin composition to be a chip-like product of the present invention comprises a polylactic acid-based resin (A), an aliphatic polyester and / or an aliphatic aromatic polyester (B), a plasticizer (C), and an organic lubricant (D In the case where the polylactic acid-based resin (A) is contained in an amount of less than 24% by mass in a total of 100% by mass, it is insufficient as a practical technology for plant-derived materials, which is the object of the present invention. In addition, the polylactic acid-based resin composition to be a chip-like material is a polylactic acid-based resin (A), an aliphatic polyester and / or an aliphatic aromatic polyester (B), a plasticizer (C), and an organic lubricant (D). When the polylactic acid resin (A) exceeds 64 mass% in a total of 100 mass%, sufficient flexibility cannot be obtained when the chip-like product of the present invention is used as a polylactic acid resin film. A composition containing a polylactic acid-based resin (A), an aliphatic polyester and / or an aliphatic aromatic polyester (B), a plasticizer (C), an organic lubricant (D), and the like constituting the chip-like material is hereinafter referred to as poly It is called a lactic acid resin composition.

  Examples of the aliphatic polyester and / or aliphatic aromatic polyester (B) other than the polylactic acid resin (A) contained in the polylactic acid resin composition constituting the chip-like product of the present invention include, for example, polyglycolic acid , Poly (3-hydroxybutyrate), poly (3-hydroxybutyrate / 3-hydroxyvalerate), polycaprolactone, or aliphatic diols such as ethylene glycol and 1,4-butanediol, succinic acid, adipic acid, etc. And aliphatic polyesters composed of aliphatic dicarboxylic acids, and copolymers of aliphatic polyesters and aromatic polyesters such as poly (butylene succinate / terephthalate) and poly (butylene adipate / terephthalate). Among them, polybutylene succinate resins such as polybutylene succinate and polybutylene succinate adipate are preferably used as those having a large improvement effect in both heat sealability and impact resistance, and in particular, polybutylene succinate Adipate is preferably used.

The use amount of the aliphatic polyester and / or the aliphatic aromatic polyester (B) other than the polylactic acid resin (A) is the polylactic acid resin (A), the aliphatic polyester and / or the aliphatic aromatic polyester (B). In the total of 100% by mass of the plasticizer (C) and the organic lubricant (D), it is important that the aliphatic polyester and / or the aliphatic aromatic polyester (B) is 10% by mass to 50% by mass. In particular, 20 mass% or more and 40 mass% or less are preferable. Aliphatic polyester and / or aliphatic in a total of 100% by mass of polylactic acid resin (A), aliphatic polyester and / or aliphatic aromatic polyester (B), plasticizer (C), and organic lubricant (D) If content of aromatic polyester (B) is less than 10 mass%, there exists a problem that the width shrinkage of a film becomes large. On the other hand, the aliphatic polyester and / or the polylactic acid resin (A), the aliphatic polyester and / or the aliphatic aromatic polyester (B), the plasticizer (C), and the organic lubricant (D) in a total of 100% by mass. If the content of the aliphatic aromatic polyester (B) exceeds 50% by mass, the film forming property tends to be lowered, and the transparency of the film tends to deteriorate.

  On the other hand, the plasticizer (C) contained in the polylactic acid resin composition in the present invention is not particularly limited as long as it can be suitably used for the polylactic acid resin (A). For example, as organic plasticizers, aliphatic alcohol plasticizers such as triethylene glycol and polyethylene glycol, aliphatic ester plasticizers such as tributyl acetylcitrate, glycerin monolauryl diacetate, triacetin, and sebacic acid, and ester modification Examples of such products include epoxidized soybean oil and epoxidized linseed oil. Preferably, a polyglycerol acetate plasticizer and an acetylated monoglyceride plasticizer are used.

  Furthermore, from the viewpoint of suppressing bleeding out of the plasticizer (C) and blocking as a chip-like product made of a polylactic acid resin composition, the plasticizer (C) used in the present invention has, for example, a number average molecular weight of 1, 000 or more polyethylene glycol or the like is preferably a solid at 20 ° C. ± 5 ° C. (Here, the solid at 20 ° C. ± 5 ° C. is a solid by visual observation after standing at 20 ° C. ± 5 ° C. for 24 hours. Is preferred). From the same viewpoint, the plasticizer (C) used in the present invention has a polyether-based segment and / or a polyester-based segment as a plasticizing component, and has a number average molecular weight of 1,200 to 10, in one molecule. A block copolymer having one or more polylactic acid segments of 0000 or less is more preferable.

  In the block copolymer plasticizer preferably used in the present invention, the number average molecular weight of the polyether segment and / or the polyester segment in one molecule of the plasticizer is preferably 7000 or more and less than 20000. By forming the number average molecular weight of the polyether-based segment and / or the polyester-based segment in one molecule of the plasticizer to be 7000 or more and less than 20000, the film was formed using the chip-like material made of the polylactic acid-based resin composition of the present invention. Stabilize the film formation by giving the polylactic acid resin film the desired flexibility and maintaining the melt mass flow rate at 170 ° C. at 15 ° C / 10 min or less when the polylactic acid resin composition and the chip-like material composed thereof are used. It is preferable also from the point which can be made.

  Next, the block copolymer plasticizer having one or more polylactic acid segments having a number average molecular weight of 1,200 or more and 10,000 or less in one molecule, and further having a polyether-based and / or polyester-based segment. A more specific example will be described.

A polyethylene glycol having a hydroxyl terminal at both ends (hereinafter referred to as PEG) is prepared. The number average molecular weight (M _PEG ) of a PEG having hydroxyl groups at both ends is usually calculated from the hydroxyl value determined by a neutralization method or the like in the case of a commercially available product. In a system in which lactide: w _A part by mass is added to PEG: w _B part by mass with PEG having both hydroxyl groups at both ends, lactide is ring-opening addition polymerized at both hydroxyl groups of PEG and sufficiently reacted. A block copolymer of the PLA (A) -PEG (B) -PLA (A) type can be obtained (wherein PLA represents polylactic acid). This reaction is performed in the presence of a catalyst such as tin octylate as necessary. The number average molecular weight of one polylactic acid-based segment of the plasticizer made of this block copolymer can be determined substantially as (1/2) × (w _A / w _B ) × M _PEG . The mass percentage of the total plasticizer polylactic acid segment component can be substantially determined as _{100 × w A / (w A} + w B)%. Furthermore, the mass ratio of the plasticizer component excluding the polylactic acid-based segment component to the entire plasticizer can be substantially calculated as 100 × w _B / (w _A + w _B )%.

  When the plasticizer (C) contains a large amount of unreacted PEG, a reaction product with PEG having a terminal polylactic acid segment molecular weight of less than 1,200, a by-product such as a lactide oligomer, or impurities. These are preferably removed, for example, by the following purification method. After uniformly dissolving the synthesized plasticizer (C) in an appropriate good solvent such as chloroform, an appropriate poor solvent such as a water / methanol mixed solution or diethyl ether is added dropwise. Alternatively, precipitation is performed by adding a good solvent solution in a large excess of poor solvent, and the solvent is evaporated after separating the precipitate by centrifugation or filtration. After immersing the plasticizer (C) in water, the mixture is heated to 50 to 90 ° C. and stirred as necessary, and then the organic phase containing the plasticizer is extracted and dried to remove water. The purification method is not limited to the above, and the above operation may be repeated a plurality of times as necessary. Removal of by-products such as lactide oligomers can prevent the polylactic acid resin (A) from decreasing in viscosity, and the melt mass flow at 170 ° C. of the chip-like material comprising the polylactic acid resin composition. It is also preferable for the rate to be 15 g / 10 min or less.

When the plasticizer (C) of the PLA (A) -PEG (B) -PLA (A) type block copolymer is prepared by the above-described method, one polylactic acid system which the prepared plasticizer (C) has The molecular weight of the segment can be determined by the following method. That is, based on a chart obtained by ¹ H-NMR measurement using a deuterated chloroform solution of a plasticizer (C), {I _PLA × (molecular weight of polylactic acid monomer unit) / (number of polylactic acid segments)} / {I _PEG × (molecular weight of PEG monomer unit) / (number of chemically equivalent protons)} × M _PEG . That is, when a plasticizer (C) of a PLA (A) -PEG (B) -PLA (A) type block copolymer is prepared, {I _PLA × 72/2} / {I _PEG × 44/4 } × M _PEG . However, I _PEG is the signal integral intensity derived from the hydrogen of the methylene group of the PEG main chain part, and I _PLA is the signal integral intensity derived from the hydrogen of the methine group of the PLA main chain part. When synthesizing under the conditions that the reaction rate of lactide during the synthesis of the plasticizer (C) is sufficiently high and almost all lactide is ring-opening added to the PEG end, it is often obtained by ¹ H-NMR measurement. It is preferable to obtain the molecular weight of one polylactic acid-based segment of the plasticizer (C) by the above method based on the chart.

  In addition, as a method of separating the used plasticizer (C) from the chip-like product composed of the polylactic acid-based resin composition in the present invention for the evaluation of the molecular weight of the polylactic acid-based segment in the plasticizer (C), etc. For example, after the polyester is uniformly dissolved in a suitable good solvent such as chloroform, a precipitate mainly containing the polylactic acid-based resin (A) is filtered by dropping it into a suitable poor solvent such as water or a water / methanol mixed solution. A reprecipitation method for removing and volatilizing the solvent of the filtrate to obtain a separated plasticizer (C) is included, but is not limited to this, and the plasticizer (C) or polylactic acid resin ( A suitable method can be selected or combined according to A) or the like.

The plasticizer (C) separated from the chip-like material for molecular weight evaluation is dissolved in a solution such as THF (tetrahydrofuran), and the number average of the plasticizer (C) using GPC (gel permeation chromatography) or the like. The molecular weight (hereinafter referred to as M) is measured, and the polylactic acid-based segment, the polyether-based segment and / or the polyester-based segment are specified by ¹ H-NMR measurement or the like. By using these measurement results, the molecular weight of one polylactic acid segment possessed by the plasticizer separated from the chip-like material comprising the polylactic acid resin composition for molecular weight evaluation can be obtained as follows. it can. That is, based on the chart obtained by ¹ H-NMR measurement, M × {1 / (number of polylactic acid segments)} × {I _PLA × (molecular weight of PLA monomer unit = 72)} / [(I _PEPE × UM _PEPE / N _PEPE ) + {I _PLA × (PLA monomer unit molecular weight = 72)}]. However, I _PEPE is the signal integrated intensity in ¹ H-NMR measurement derived from the polyether segment and / or the polyester segment, UM _PEPE is the molecular weight of the monomer unit of the polyether segment and / or the polyester segment, N _PEPE is the number of chemically equivalent protons that give signal integral strength among polyether-based segments and / or polyester-based segments.

  For example, PLA (A) -PEG (B) -PLA (A) type obtained by the above-described method and having one or more polylactic acid-based segments having a number average molecular weight of 1,200 or more and less than 10,000 in one molecule If this block copolymer is used as a plasticizer (C), it has sufficient flexibility and can suppress volatilization, leaching and extraction (bleed out) of the plasticizer (C), which could not be achieved by the prior art. A chip-like material for obtaining a polylactic acid-based resin film can be provided.

  As a method of adding the above-mentioned plasticizer (C) to the polylactic acid resin (A), the plasticizer (C) is added and melted at a desired mass ratio in the molten state of the polylactic acid resin (A). Although it can be obtained by kneading, from the viewpoint of increasing the degree of polymerization of the polylactic acid resin (A) and suppressing residual low molecular weight substances such as lactide, the plasticity after the polymerization reaction of the polylactic acid resin (A) is completed. It is preferable to add and melt knead the agent (C). A method in which the plasticizer (C) is added and melt-kneaded after the completion of the polymerization reaction of the polylactic acid resin (A) is preferable because residual low molecular weight substances can be reduced in the polylactic acid resin (A). As the addition / melt kneading of the polylactic acid resin (A) and the plasticizer (C) described above, for example, immediately after the completion of the polycondensation reaction, the plasticizer (C) is added to the molten polylactic acid resin (A). A method of stirring and melt-kneading, a method of adding and mixing a plasticizer (C) to a chip of polylactic acid resin (A), and then melt-kneading with a reaction vessel or an extruder, etc., plasticizing a polylactic acid resin (A) with an extruder A method of continuously adding the agent (C), melt-kneading, mixing a polylactic acid resin (A) master chip containing a high concentration of the plasticizer (C) and a homo chip of the polylactic acid resin (A) It can be carried out by a melt kneading method using an extruder or the like.

  Regarding the content of the plasticizer (C), the total amount of the polylactic acid resin (A), the aliphatic polyester and / or the aliphatic aromatic polyester (B), the plasticizer (C), and the organic lubricant (D) is 100 mass. %, The plasticizer (C) is 5 to 30% by mass, preferably 10 to 25% by mass. The content of the plasticizer (C) in a total of 100% by mass of the polylactic acid resin (A), aliphatic polyester and / or aliphatic aromatic polyester (B), plasticizer (C), and organic lubricant (D) is If it is less than 5% by mass, the plasticizing effect is not sufficient, and if it exceeds 30% by mass, the chip-like product composed of the polylactic acid-based resin composition and the film obtained therefrom are excessively tacky, resulting in poor workability. is there.

  The chip-like product of the present invention has a polylactic acid resin (A), aliphatic polyester and / or aliphatic aromatic polyester (B), plasticizer (C), and organic lubricant (D) in a total of 100% by mass, The organic lubricant (D) needs to be contained in an amount of 0.1% by mass to 5% by mass, and preferably 0.5% by mass to 3% by mass. The content of the organic lubricant (D) is 100% by mass in total of the polylactic acid resin (A), the aliphatic polyester and / or the aliphatic aromatic polyester (B), the plasticizer (C), and the organic lubricant (D). When the content is less than 0.1% by mass, the chip-like product is inferior in handling, and blocking tends to occur particularly during drying. When the content of the organic lubricant (D) exceeds 5% by mass, the organic lubricant (D) bleeds. Out is likely to occur, blocking is also likely to occur during drying, and problems such as a decrease in melt viscosity, deterioration in workability, and poor appearance such as bleeding out and haze up when formed into a film are likely to occur.

  On the other hand, examples of the organic lubricant (D) include aliphatic hydrocarbons such as liquid paraffin, natural paraffin, synthetic paraffin, and polyethylene, stearic acid, lauric acid, hydroxystearic acid, fatty acid such as hard castor oil, and stearic acid amide. , Fatty acid amides such as oleic acid amide, erucic acid amide, lauric acid amide, ethylene bis-stearic acid amide, ethylene bis-oleic acid amide, ethylene bis-lauric acid amide, aluminum stearate, lead stearate, calcium stearate, magnesium stearate Fatty acid metal salts such as glycerin fatty acid esters, fatty acid (partial) esters of polyhydric alcohols such as rubitan fatty acid esters, long chain fats such as long chain ester waxes such as butyl stearate and montan wax Ester and the like. Of these, stearic acid amide and ethylene bis stearic acid amide, which are easy to obtain an effect in a small amount due to appropriate compatibility with the polylactic acid resin (A), are preferable.

  Further, the chip-like product of the present invention is required to have a melt mass flow rate at 170 ° C. (measured in accordance with JIS-K7210) of 15 g / 10 min or less, and preferably 11 g / 10 min or less. When the melt mass flow rate exceeds 15 g / 10 min, discharge is likely to be unstable when the chip-like product of the present invention is produced by a twin-screw extruder or the like, and blocking due to partial fusion is likely to occur when drying. . In addition, the film obtained using the chip-like product of the present invention is too soft and the film formation tends to be unstable. In particular, in the inflation method, the film reacts sensitively to the increase or decrease in the amount of air blown into the inside, and the film formation is not good. In the case of the top blowing inflation method, the polymer drips and film formation is impossible. Further, the melt mass flow rate at 170 ° C. is preferably as low as possible so that extrusion is possible, but according to the current technical level, the lower limit is considered to be about 0.1 g / 10 min.

  In order to set the melt mass flow rate to 15 g / 10 min or less, the types of polylactic acid resin (A), aliphatic polyester and / or aliphatic aromatic polyester (B), plasticizer (C), and organic lubricant (D) The content may be appropriately selected. For example, as the polylactic acid resin (A), the aliphatic polyester and / or the aliphatic aromatic polyester (B), a high-viscosity type is selected within a range where the processability is not hindered. For example, a method of selecting a high molecular weight type as the plasticizer (C) or using a plasticizer with high plasticization efficiency and reducing the addition amount of the plasticizer (C) is effective. Further, when processing into chips, the water content of the polylactic acid resin (A), the aliphatic polyester and / or the aliphatic aromatic polyester (B) is 600 ppm in advance (here, ppm is based on weight) The same shall apply hereinafter.) A compound having low water absorption is selected as the plasticizer (C), and the moisture content is set to 1800 ppm or less in advance, and the temperature and time for melting and kneading are within a range that does not hinder processing. -It is also effective to use short-term conditions.

  On the other hand, the chip-like product made of the polylactic acid resin composition of the present invention can be colored simultaneously with the molding process by further containing the pigment (E). The pigment (E) used in the present invention is a conventionally used ordinary pigment, for example, organic pigments such as azo, phthalocyanine, quinacridone, dioxazine, perylene, and isoindolinone. Inorganic pigments such as titanium oxide, bengara, red, and carbon black are listed. In the present invention, these organic pigments and inorganic pigments are used alone or in combination. The film obtained by adding the pigment (E) to color the chip-like material, the film obtained using the chip-like material of the present invention can be used for agricultural purposes such as agricultural multi-films and pine worm fumigation sheets and garbage. It can be utilized for bags, compost bags, or various packaging applications.

Among these, a pigment that does not release harmful pigments into the environment when the biodegradable resin is decomposed in the environment or soil is preferable. From this point of view, the pigment (E) is selected from the group consisting of carbon black, titanium dioxide, iron black (Fe ₃ O ₄ ), dial (Fe ₂ O ₃ ), magnesium ferrous oxide, ultramarine and bitumen. Inorganic pigments are useful. Among these, titanium dioxide can be used as a white pigment, carbon black or iron black can be used as a black pigment, the petite can be used as a red pigment, magnesium sulfite can be used as a yellow pigment, and ultramarine and bitumen can be used as blue pigments.

  The content of the pigment (E) in the chip-like product of the present invention is as follows: polylactic acid resin (A), aliphatic polyester and / or aliphatic aromatic polyester (B), plasticizer (C), organic lubricant (D) , And pigment (E) in a total of 100% by mass, it is preferably 0.01% by mass or more and 20% by mass or less. Pigment (E) in a total of 100% by mass of polylactic acid resin (A), aliphatic polyester and / or aliphatic aromatic polyester (B), plasticizer (C), organic lubricant (D), and pigment (E) If the content is less than 0.01% by mass, the coloring is insufficient. On the other hand, if the content exceeds 20% by mass, the flexibility of the film obtained by film formation becomes poor, and the mechanical properties such as the tear strength. There arises a problem of a large decrease in. In addition, content, such as polylactic acid-type resin (A) in the case of containing a pigment (E), is as above-mentioned, Polylactic acid-type resin (A), aliphatic polyester, and / or aliphatic aromatic polyester (B) , The plasticizer (C), the organic lubricant (D), and the pigment (E) in a total of 100% by mass, the polylactic acid resin (A) is from 24% by mass to 64% by mass, aliphatic polyester and / or aliphatic The aromatic polyester (B) is 10% by mass to 50% by mass, the plasticizer (C) is 5% by mass to 30% by mass, the organic lubricant (D) is 0.1% by mass to 5% by mass, a pigment ( E) is preferably 0.01% by mass or more and 20% by mass or less.

  In addition, the polylactic acid resin (A), the aliphatic polyester and / or the aliphatic aromatic polyester (B), the plasticizer (C), in a total amount of 100% by mass of the polylactic acid resin composition constituting the chip-like material, The total amount of the organic lubricant (D) and the pigment (E) is preferably 80% by mass or more and 100% by mass or less, more preferably 90% by mass or more and 100% by mass or less, and 95% by mass or more and 100% by mass. More preferably, it is at most mass%.

  On the other hand, in the chip-like product composed of the polylactic acid-based resin composition of the present invention, the polylactic acid-based resin composition (chip-like) is used to prevent the film from sticking to the metal roll during molding or blocking the films from each other. It is also possible to include inorganic particles, organic particles, crosslinked polymer particles, etc. in the product.

  The inorganic particles are not particularly limited, but silicon oxide such as silica, various carbonates such as calcium carbonate, magnesium carbonate and barium carbonate, various sulfates such as calcium sulfate and barium sulfate, various composite oxides such as kaolin and talc. Fine particles comprising various phosphates such as lithium phosphate, calcium phosphate, and magnesium phosphate, various oxides such as aluminum oxide, titanium oxide, and zirconium oxide, and various salts such as lithium fluoride can be used.

  As the organic particles, fine particles made of calcium oxalate, terephthalate such as calcium, barium, zinc, manganese, magnesium, or the like are used.

  Examples of the crosslinked polymer particles include fine particles made of a vinyl monomer such as divinylbenzene, styrene, acrylic acid or methacrylic acid, or a copolymer. In addition, organic fine particles such as polytetrafluoroethylene, benzoguanamine resin, thermosetting epoxy resin, unsaturated polyester resin, thermosetting urea resin, and thermosetting phenol resin are also preferably used.

  The blending amount of these fine particles is 0.05 to 2% by weight, preferably 0.1 to 1.5% by weight, with respect to 100% by weight of the polylactic acid resin composition constituting the chip-like material. When the blending amount is less than 0.05% by weight, the effect of improving the adhesion to the processing roll of the melt film using the chip-like material composed of the polylactic acid resin composition and the blocking between the films is poor, and the content exceeds 2% by weight. And the transparency of the film using the chip-like material comprising the polylactic acid resin composition is likely to be impaired.

  Furthermore, the heat of crystal fusion ΔHpl of the chip-like product made of the polylactic acid resin composition of the present invention is preferably 5 J / g or more and 40 J / g or less. This heat of crystal melting is a value measured in a region where the temperature at the time of temperature increase is 120 ° C. or higher using a differential scanning calorimeter. If the heat of crystal fusion ΔHpl of the chip-like product is less than 5 J / g, the handling property of the chip-like product is inferior, and blocking may occur particularly during drying. On the other hand, when the amount of heat of crystal melting ΔHpl of the chip-like product exceeds 40 J / g, the plasticizer (C) cannot be retained and the plasticizer (C) bleeds out as the amorphous region decreases due to the improved crystallinity of the resin. May be likely to occur.

  The chip-like product comprising the polylactic acid resin composition of the present invention may be made into a chip-like product having a moisture content of 1000 ppm or less by drying the polylactic acid resin to be used at 60 to 110 ° C. for 6 hours or more. preferable. When the moisture content of the chip-like material exceeds 1000 ppm, hydrolysis may occur during melt-kneading, and the molecular weight of the polylactic acid resin (A) may decrease. More preferably, the moisture content of the chip-like material is 600 ppm or less. The moisture content of the chip-like material is preferably as small as possible. However, long-time drying is required to reduce the moisture content to less than 50 ppm, and the chip-like material may be deteriorated by long-time drying. The lower limit of the rate is preferably about 50 ppm.

  Other components can also be added to the chip-like product made of the polylactic acid resin composition used in the present invention within a range not impairing the effects of the present invention. Examples of such additive components include antioxidants, ultraviolet absorbers, hindered amine light stabilizers, antistatic agents, thermal stabilizers, nucleating agents, tackifiers, pigments, dyes, and various polymers. (For example, EVA resin).

  The chip-like product comprising the polylactic acid resin composition of the present invention can be produced by a general method. Specifically, a desired raw material is dry-mixed with a Henschel mixer or a ribbon mixer, and supplied to a known melt-kneader such as a single-screw or twin-screw extruder, a Banbury mixer, a kneader, or a mixing roll, and melt-kneaded. Can do. For example, first, each resin composition is put into a tumbler and stirred and mixed for 10 to 20 minutes. Next, it is melt kneaded at a temperature of 140 to 210 ° C. with a single-screw or twin-screw extruder, etc., and extruded into a gut shape, then cooled and solidified in a water bath and cut into a fixed length, etc. A chip-like product made of a polylactic acid-based resin composition can be produced by forming a pellet of the composition.

When the chip-like product comprising the polylactic acid resin composition of the present invention is used as a melt-molded product such as a colored film containing the pigment (E), the polylactic acid (A), aliphatic polyester and / or Alternatively, a chip-shaped product of a composition containing an aliphatic aromatic polyester (B), a plasticizer (C), and an organic lubricant (D) and a so-called masterbatch containing a pigment (E) at a high concentration in polylactic acid are separately provided. These can be prepared and mixed in the desired proportions and provided, for example, to a single screw extruder. However, in general, a master batch containing a pigment at a high concentration may have a higher melt viscosity than a base polymer (here, polylactic acid) alone. In some cases, it cannot be sufficiently dispersed. In such a case, in addition to polylactic acid (A), aliphatic polyester and / or aliphatic aromatic polyester (B), plasticizer (C), organic lubricant (D), pigment (E) is also added from the beginning, Simultaneously melt-kneading to once form a chip-like product, and using this, a melt-molded product with sufficiently enhanced dispersibility of the pigment (E) can be obtained.

  Examples of the shape of the chip-like product comprising the polylactic acid-based resin composition of the present invention include a sphere, a spheroid, a bowl, a dice, and the like. It is preferable that it is a chip-like product having an aspect ratio of 1: 1 to 10: 1. Examples of the chip-like material referred to in the present invention include, for example, various pellets used for film formation of general films, flakes obtained by pulverizing films and sheets, lump-like materials, and other shapes of pulverized materials. .

  On the other hand, in producing a polylactic acid resin film using a chip-like material comprising the polylactic acid resin composition of the present invention, existing methods such as a known T-die casting method, an inflation method, and a tubular method are used. Can be adopted. In order to produce a flexible film stably and economically, the inflation method is particularly preferable.

  In the case of producing by the inflation method in the present invention, for example, a chip-like product made of a polylactic acid resin composition prepared by the method as described above is heated and melted in a twin-screw extruder with a vent hole and extruded into an annular die. , Extruded from an annular die, supplied with dry air inside to form a balloon (bubble), further air-cooled and solidified uniformly with an air ring, and taken up at a predetermined take-up speed while folded flat with a nip roll, then necessary Depending on the situation, both ends or one end may be cut open and wound.

  In addition, the extrusion temperature of the chip-like product composed of the polylactic acid-based resin composition is usually in the range of 150 to 240 ° C., but to suppress a thickness error in order to impart a good roll winding shape and unwinding property, Further, the temperature of the annular die is important for imparting an appropriate heat shrinkage rate, preferably the temperature of the annular die is in the range of 150 to 190 ° C, more preferably in the range of 150 to 170 ° C.

  Furthermore, after forming into a film, various surface treatments may be applied for the purpose of improving printability, laminate suitability, coating suitability, and the like. Examples of the surface treatment include corona discharge treatment, plasma treatment, flame treatment, acid treatment, etc., and any method can be used, but continuous treatment is possible, and equipment for existing film forming equipment is used. Corona discharge treatment can be exemplified as the most preferable because of its easy installation and simple processing.

Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited thereto.
[Measurement and evaluation method of characteristics]
(1) Melt mass flow rate value of chip-like material [g / 10 min]
After the chip-like product sample is dried or the like to reduce the moisture content to 700 ppm or less, in accordance with JIS-K7210 B method (1976), the melt mass flow rate at a load of 2.16 kg and a temperature of 170 ° C. with a melt indexer. The value was measured. The moisture content was measured according to (3) moisture content measurement described later.
(2) Heat of crystal melting ΔHpl
After the chip sample was dried under reduced pressure at 30 ° C. for 12 hours, 4.0 mg was weighed to prepare a sample.

Using a DSC7 differential scanning calorimeter manufactured by PerkinElmer, Inc., the temperature was raised from −50 ° C. to 200 ° C. at a temperature rising rate of 20 ° C./min under a nitrogen gas flow to obtain a DSC curve. In the DSC curve chart, the amount of heat of crystallization and the amount of heat of fusion (J / g) per gram of the sample were measured from the area of the crystallization peak and the melting peak that appeared in the region where the temperature at the time of temperature increase was 120 ° C. or higher.
(3) Moisture content measurement [ppm]
Using a Karl Fischer moisture meter MKC-510N (Kyoto Electronics Industry Co., Ltd.), measurement was performed by the Karl Fischer method (coulometric titration method). The heating conditions during the measurement were 150 ° C.
(4) Film flexibility and elastic modulus
A film sample was cut into a longitudinal direction of 150 mm and a width direction of 10 mm, and conditioned for 24 hours in an atmosphere of a temperature of 23 ° C. and a humidity of 65% RH in advance. This sample was subjected to a tensile test under the conditions of an initial length of 50 mm and a tensile speed of 300 mm / min using a Tensilon universal testing machine UTC-100 (manufactured by Orientec Co., Ltd.) in an atmosphere of 23 ° C. according to JIS K7127 (1989). And the tensile modulus in the longitudinal direction was measured.

The measurement was performed 5 times in total, and the average value was obtained and used as the tensile modulus, and evaluated according to the following criteria.
A: Range in which the tensile modulus is 0.1 GPa or more and less than 1.0 GPa ○: Range in which the tensile modulus is 1.0 GPa or more and less than 1.5 GPa Δ: Range in which the tensile modulus is 1.5 GPa or more and less than 2.0 GPa ×: (5) Haze value of film Haze value was measured using “Haze Meter” HGM-2DP type manufactured by Suga Test Instruments Co., Ltd. The measurement was performed 5 times for each level, and the average value of the 5 measurements was determined according to the following formula.

Haze: Ha (%) = Td / Tt × 100
Td: Diffuse transmittance, Tt: Total light transmittance (6) Film width shrinkage The film width immediately after film formation was measured and set to L1 (mm) and left in the product state for 1 hour at 23 ° C. The film width is measured and set to L2 (mm). From this value, film width shrinkage (mm) = L1-L2.
The measurement was performed three times in total, and the average value was obtained and used as the width shrinkage of the film.
A: Film shrinkage 0 to 1 mm
○: Film shrinkage 1 to 4 mm
Δ: film shrinkage 4 to 10 mm
X: Film shrinkage 10 mm or more (7) Bleed-out property of chip-like product during drying The chip-like product was dried for 10 hours with dehumidified hot air at a temperature of 80 ° C and a dew point of -25 ° C. Immediately after taking out, the state was confirmed and evaluated according to the following criteria: No bleed was observed.
Δ: Slightly bleed on the surface of the chip, but not so much that the chips stick to each other. X: Sticking between the chips was observed on the surface of the chips.
(8) Blocking property of the chip-like product at the time of drying The chip-like product was dried for 5 hours with dehumidified hot air at a temperature of 80 ° C. and a dew point of −25 ° C., taken out, immediately checked for condition, and evaluated according to the following criteria.
A: No blocking was observed.
○: There was a blocking to a size of 10 grains or less, but it was easily loosened by hand.
Δ: Some were blocked to a size of 10 grains or more, but were easily loosened by hand.
X: What was blocked to the size of 10 or more grains was generated and firmly fixed.
(9) Inflation film forming property Inflation film forming property was evaluated according to the following criteria.
○: Bubbles can be blown up and the film formation was stable without breaking for 12 hours.
Δ: Although it was blown up in a bubble shape, it was slightly unstable, and after film formation for 12 hours, it was torn 1 to 5 times.
X: Although it was able to blow up like a bubble, it was unstable, and after 12 hours of film formation, it was torn 6 times or more, or film formation was impossible.
[Polylactic acid resin used]
Polylactic acid P1
D body content = 12.0 wt%, melt mass flow rate = 3 g / 10 min,
Water content = 490 ppm, Tm = none, weight average molecular weight = 200,000
Polylactic acid P2
D-form content = 1.4 wt%, melt mass flow rate = 2 g / 10 min,
Water content = 360 ppm, Tm = 166 ° C., weight average molecular weight = 220,000
Polylactic acid P3
D body content = 1.4 wt%, melt mass flow rate = 30 g / 10 min
Water content = 450 ppm, Tm = 166 ° C., weight average molecular weight = 110,000
Polylactic acid P4
D-form content = 4.0 wt%, melt mass flow rate = 2 g / 10 min
Water content = 380 ppm, Tm = 153 ° C., weight average molecular weight = 220,000
The weight average molecular weight was measured by using Waters 2690 manufactured by Japan Waters Co., Ltd., using polymethyl methacrylate as a standard, a column temperature of 40 ° C., and a chloroform solvent.

[Method for producing plasticizer]
Plasticizer S1
By mixing 62% by weight of polyethylene glycol having a number average molecular weight of 8000, 38% by weight of L-lactide and 0.025% by weight of tin octylate and polymerizing at 150 ° C. for 3 hours in a nitrogen atmosphere, there are several at both ends of the polyethylene glycol. A plasticizer S1 having a polylactic acid segment having an average molecular weight of 2500 was obtained. When the water content was measured, it was 1650 ppm.
Plasticizer S2
By mixing 62% by weight of polyethylene glycol having a number average molecular weight of 10,000, 38% by weight of L-lactide and 0.025% by weight of tin octylate and polymerizing at 150 ° C. for 3 hours in a nitrogen atmosphere, there are several at both ends of the polyethylene glycol. A plasticizer S2 having a polylactic acid segment with an average molecular weight of 2400 was obtained. The water content was measured and found to be 1380 ppm.
Plasticizer S3
By mixing 62% by weight of polyethylene glycol having a number average molecular weight of 6000, 38% by weight of L-lactide and 0.025% by weight of tin octylate and polymerizing at 150 ° C. for 3 hours in a nitrogen atmosphere, the number of both ends of polyethylene glycol is several. A plasticizer S3 having a polylactic acid segment with an average molecular weight of 2300 was obtained. The water content was measured and found to be 1500 ppm.
Plasticizer S4
Polyethylene glycol having a number average molecular weight of 8,000. The water content was measured and found to be 1700 ppm.
Plasticizer S5
Acetyltributyl citrate (manufactured by Morimura Shoji Co., Ltd., “Citroflex A-4”, water content: 1000 ppm).
[Additives used]
Organic lubricant SL1
Stearic acid amide (Nippon Yushi Co., Ltd., “Alflow S-10”)
Additive A1
Carbodiimide-modified isocyanate (manufactured by Nisshinbo Co., Ltd., “Carbodilite LA-1”)
Polyester PA1
Polybutylene succinate and adipate resin (manufactured by Showa Polymer Co., Ltd., “Bionore # 3001”), melt mass flow rate = 1.4
Polyester PA2
Polybutylene succinate / adipate resin (Mitsubishi Chemical Corporation, trade name “GSPla” AD92W), melt mass flow rate = 4.5
Polyester PA3
Polybutylene succinate / adipate resin (manufactured by Showa Polymer Co., Ltd., trade name, “Bionole # 3003), melt mass flow rate = 5
Polyester PA4
Polybutylene succinate resin (product name “Bionore” # 1003, manufactured by Showa Polymer Co., Ltd.) Melt mass flow rate = 5
Polyester PA5
Polybutylene succinate resin (Mitsubishi Chemical Corporation, trade name “GSPla” AZ91TN), melt mass flow rate = 4.5
Polyester PA6
Polybutylene terephthalate / adipate resin (BASF, trade name Ecoflex)
[Pigments used]
Pigment Master MB1
Carbon black master Carbon black particles 20% by weight and polylactic acid P4 80% by weight Kneaded pigment Master MB2
Kneaded mixture of 27% by weight of brown master iron oxide particles and 73% by weight of polylactic acid P4
Pigment Master MB3
Mixture of titanium oxide master titanium oxide particles 50% by weight and polylactic acid P4 50% by weight [Preparation of polylactic acid resin composition]
( Reference Example 1)
A mixture of 32% polylactic acid P1, 12% polylactic acid P2, 30% polyester PA1, 25% plasticizer S1 and 1.0% organic lubricant SL1 is a screw having a cylinder temperature of 190 ° C. It is used in a twin screw extruder with a 44 mm diameter vacuum vent, melted and kneaded while degassing the vacuum vent part, homogenized and extruded into a gut shape, then cooled and solidified in a water bath and cut to obtain a resin composition chip It was.

  This chip was dried with dehumidified hot air at a temperature of 100 ° C. and a dew point of −25 ° C. for 5 hours. The evaluation results of the obtained chip are shown in Table 1.

  This chip is supplied to a single-screw extruder with a screw diameter of 65 mm at an extruder cylinder temperature of 190 ° C., and from a spiral annular die with a diameter of 250 mm, a lip clearance of 1.3 mm, and a temperature of 165 ° C. at a blow ratio of 3.4. Then, it was air-cooled with a cooling ring, taken up at 20 m / min while being folded with a nip roll above the die, cut at both ends with an edge cutter, and cut into two pieces, each wound with a winder. . A film having a final thickness of 20 μm was obtained by adjusting the discharge amount.

The evaluation results of the obtained film are shown in Table 1.
( Reference Example 2)
A mixture of 32% by weight of polylactic acid P1, 12% by weight of polylactic acid P2, 30% by weight of polyester PA2, 25% by weight of plasticizer S1, and 1.0% by weight of organic lubricant SL1 is a screw having a cylinder temperature of 190 ° C. A chip was obtained by using a twin screw extruder with a 44 mm diameter vacuum vent, melted and kneaded while degassing the vacuum vent part, homogenized, extruded into a gut shape, cooled and solidified in a water bath and cut.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 1.
( Reference Example 3)
A mixture of 32% by weight of polylactic acid P1, 12% by weight of polylactic acid P2, 30% by weight of polyester PA3, 25% by weight of plasticizer S1, and 1.0% by weight of organic lubricant SL1 is a screw diameter at a cylinder temperature of 190 ° C. A chip was obtained by using a 44 mm twin-screw extruder equipped with a vacuum vent, melt-kneading while homogenizing the vacuum vent and extruding it into a gut shape, cooling and solidifying in a water bath and cutting. This chip was dried with dehumidified hot air at a temperature of 100 ° C. and a dew point of −25 ° C. for 5 hours.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 1.
( Reference Example 4)
A mixture of 32% by weight of polylactic acid P1, 12% by weight of polylactic acid P2, 30% by weight of polyester PA4, 25% by weight of plasticizer S1, 1.0% by weight of organic lubricant SL1, and a screw diameter at a cylinder temperature of 190 ° C. A resin composition chip was obtained by subjecting it to a twin screw extruder with a 44 mm vacuum vent, melt-kneading while homogenizing the vacuum vent part, extruding it into a gut shape, cooling and solidifying in a water bath and cutting. . This chip was dried with dehumidified hot air at a temperature of 100 ° C. and a dew point of −25 ° C. for 5 hours.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 1.
( Reference Example 5)
A mixture of 32% by weight of polylactic acid P1, 12% by weight of polylactic acid P2, 30% by weight of polyester PA5, 25% by weight of plasticizer S1, and 1.0% by weight of organic lubricant SL1 is a screw diameter at a cylinder temperature of 190 ° C. A chip was obtained by using a 44 mm twin-screw extruder equipped with a vacuum vent, melt-kneading while homogenizing the vacuum vent and extruding it into a gut shape, cooling and solidifying in a water bath and cutting. This chip was dried with dehumidified hot air at a temperature of 100 ° C. and a dew point of −25 ° C. for 5 hours.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 1.

(Example 6)
A mixture of 32% by weight of polylactic acid P1, 12% by weight of polylactic acid P2, 30% by weight of polyester PA6, 25% by weight of plasticizer S1 and 1.0% by weight of organic lubricant SL1 is a screw diameter at a cylinder temperature of 190 ° C. A chip was obtained by using a 44 mm twin-screw extruder equipped with a vacuum vent, melt-kneading while homogenizing the vacuum vent and extruding it into a gut shape, cooling and solidifying in a water bath and cutting. This chip was dried with dehumidified hot air at a temperature of 100 ° C. and a dew point of −25 ° C. for 5 hours.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 1 ( Reference Example 7).
Screw diameter of a mixture of 22% by weight of polylactic acid P1, 8% by weight of polylactic acid P2, 44% by weight of polyester PA1, 25% by weight of plasticizer S1 and 1.0% by weight of organic lubricant SL1 at a cylinder temperature of 190 ° C. A chip was obtained by using a 44 mm twin-screw extruder equipped with a vacuum vent, melt-kneading while homogenizing the vacuum vent and extruding it into a gut shape, cooling and solidifying in a water bath and cutting.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 1.
( Reference Example 8)
Screw diameter of a mixture of 18% polylactic acid P1, 6% polylactic acid P2, 50% polyester PA1, 25% plasticizer S1 and 1.0% organic lubricant SL1 at a cylinder temperature of 190 ° C. A chip was obtained by using a 44 mm twin-screw extruder equipped with a vacuum vent, melt-kneading while homogenizing the vacuum vent and extruding it into a gut shape, cooling and solidifying in a water bath and cutting. This chip was dried with dehumidified hot air at a temperature of 100 ° C. and a dew point of −25 ° C. for 5 hours.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 1.
( Reference Example 9)
A mixture of 47% by weight of polylactic acid P1, 17% by weight of polylactic acid P2, 10% by weight of polyester PA1, 25% by weight of plasticizer S1, 1.0% by weight of organic lubricant SL1, and a screw diameter at a cylinder temperature of 190 ° C. A chip was obtained by using a 44 mm twin-screw extruder equipped with a vacuum vent, melt-kneading while homogenizing the vacuum vent and extruding it into a gut shape, cooling and solidifying in a water bath and cutting.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 1 ( Reference Example 10).
25% by weight of polylactic acid P1, 9% by weight of polylactic acid P2, 30% by weight of polyester PA1, 25% by weight of plasticizer S1, 2% by weight of carbon black (10% by weight of pigment master MB1), and organic lubricant SL1 The 1.0 wt% mixture was supplied to a twin screw extruder with a cylinder diameter of 190 ° C and a screw diameter of 44 mm and equipped with a vacuum vent, melted and kneaded while degassing the vacuum vent, extruded into a gut shape, and then placed in a water bath. Chips were obtained by solidification by cooling and cutting. This chip was dried with dehumidified hot air at a temperature of 100 ° C. and a dew point of −25 ° C. for 5 hours.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 1.
( Reference Example 11)
31.7% by weight of polylactic acid P1, 11.8% by weight of polylactic acid P2, 30% by weight of polyester PA1, 25% by weight of plasticizer S1, 0.1% by weight of iron oxide (0.5% of pigment master MB2) Wt%) and 1.0 wt% mixture of organic lubricant SL1 were supplied to a twin screw extruder with a vacuum diameter of 44 mm with a cylinder temperature of 190 ° C. and melt kneaded and homogenized while degassing the vacuum vent. After extruding into a shape, the chip was obtained by cooling and solidifying in a water bath and cutting. This chip was dried with dehumidified hot air at a temperature of 100 ° C. and a dew point of −25 ° C. for 5 hours.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 1.
( Reference Example 12)
3% by weight of polylactic acid P1, 1% by weight of polylactic acid P2, 30% by weight of polyester PA1, 25% by weight of plasticizer S1, 20% by weight of titanium oxide (40% by weight of pigment master MB3), and organic lubricant SL1 The 1.0 wt% mixture was supplied to a twin screw extruder with a cylinder diameter of 190 ° C and a screw diameter of 44 mm and equipped with a vacuum vent, melted and kneaded while degassing the vacuum vent, extruded into a gut shape, and then placed in a water bath. Chips were obtained by solidification by cooling and cutting. This chip was dried with dehumidified hot air at a temperature of 100 ° C. and a dew point of −25 ° C. for 5 hours.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 1.
( Reference Example 13)
A mixture of 32% by weight of polylactic acid P1, 12% by weight of polylactic acid P2, 30% by weight of polyester PA1, 25% by weight of plasticizer S5, 1.0% by weight of organic lubricant SL1, and a screw diameter at a cylinder temperature of 190 ° C. A chip was obtained by using a 44 mm twin-screw extruder equipped with a vacuum vent, melt-kneading while homogenizing the vacuum vent and extruding it into a gut shape, cooling and solidifying in a water bath and cutting. This chip was dried with dehumidified hot air at a temperature of 100 ° C. and a dew point of −25 ° C. for 5 hours.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 1.
( Reference Example 14)
Screw diameter of a mixture of 41% by weight of polylactic acid P1, 18% by weight of polylactic acid P2, 30% by weight of polyester PA1, 10% by weight of plasticizer S1 and 1.0% by weight of organic lubricant SL1 at a cylinder temperature of 190 ° C. A chip was obtained by using a 44 mm twin-screw extruder equipped with a vacuum vent, melt-kneading while homogenizing the vacuum vent and extruding it into a gut shape, cooling and solidifying in a water bath and cutting.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 1.
( Reference Example 15)
Screw diameter of a mixture of 33% polylactic acid P1, 7% polylactic acid P2, 30% polyester PA1, 29% plasticizer S4, 1.0% organic lubricant SL1 and 1.0% organic lubricant SL1 at a cylinder temperature of 190 ° C. A chip was obtained by using a 44 mm twin-screw extruder equipped with a vacuum vent, melt-kneading while homogenizing the vacuum vent and extruding it into a gut shape, cooling and solidifying in a water bath and cutting.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 1.
( Reference Example 16)
A mixture of 33% by weight of polylactic acid P1, 7% by weight of polylactic acid P2, 30% by weight of polyester PA1, 29% by weight of plasticizer S2, 1.0% by weight of organic lubricant SL1, and a screw diameter at a cylinder temperature of 190 ° C. A chip was obtained by using a 44 mm twin-screw extruder equipped with a vacuum vent, melt-kneading while homogenizing the vacuum vent and extruding it into a gut shape, cooling and solidifying in a water bath and cutting.

The film formation and film evaluation were carried out in the same manner as in Reference Example 1 except that this chip was used in an extruder as a mixture of 70% by weight and polyester PA1 as 30% by weight. The results are shown in Table 1.
( Reference Example 17)
A mixture of 26% by weight of polylactic acid P1, 9% by weight of polylactic acid P2, 30% by weight of polyester PA1, 22% by weight of plasticizer S1, 1.0% by weight of organic lubricant SL1, and a screw having a cylinder temperature of 190 ° C. A chip was obtained by using a twin screw extruder with a 44 mm diameter vacuum vent, melted and kneaded while degassing the vacuum vent part, homogenized, extruded into a gut shape, cooled and solidified in a water bath and cut.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 1.
(Comparative Example 1)
A mixture of polylactic acid P1 54 wt%, polylactic acid P2 20 wt%, plasticizer S1 25 wt%, organic lubricant SL1 1.0 wt%, twin shaft with vacuum vent of cylinder temperature 190 ° C and screw diameter 44mm It was subjected to an extruder, melted and kneaded while degassing the vacuum vent part, homogenized and extruded into a gut shape, and then cooled and solidified in a water bath to obtain a chip.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 2. Film width shrinkage is inferior.
(Comparative Example 2)
A mixture of 23% by weight of polylactic acid P1, 12% by weight of polylactic acid P2, 30% by weight of polyester PA1, 25% by weight of plasticizer S1, and 10% by weight of organic lubricant SL1 was mixed at a cylinder temperature of 190 ° C. with a screw diameter of 44 mm. It was used in a twin screw extruder with a vacuum vent, melted and kneaded while degassing the vacuum vent part, homogenized and extruded into a gut shape, then cooled and solidified in a water bath to obtain a chip.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 2. When dried, the chip bleed-out property and inflation film-forming property were reduced.
(Comparative Example 3)
Screw diameter of a mixture of 12% polylactic acid P1, 4% polylactic acid P2, 80% polyester PA1, 3% plasticizer S1 and 1.0% organic lubricant SL1 at a cylinder temperature of 190 ° C A chip was obtained by using a 44 mm twin-screw extruder equipped with a vacuum vent, melt-kneading while homogenizing the vacuum vent and extruding it into a gut shape, cooling and solidifying in a water bath and cutting.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 2. The film was not flexible enough.
(Comparative Example 4)
A mixture of 48% by weight of polylactic acid P1, 18% by weight of polylactic acid P2, 30% of polyester PA1, 3% by weight of plasticizer S1, 1.0% by weight of organic lubricant SL1, and a screw diameter of 44 mm at a cylinder temperature of 190 ° C. Then, the mixture was melted and kneaded while degassing the vacuum vent part, homogenized, extruded into a gut shape, cooled, solidified in a water bath, and cut to obtain a chip.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 2. The film was not flexible enough.
(Comparative Example 5)
A mixture of 33% by weight of polylactic acid P1, 12% by weight of polylactic acid P2, 30% by weight of polyester PA1 and 25% by weight of plasticizer S1 is mixed into a twin screw extruder equipped with a vacuum vent with a cylinder diameter of 190 ° C. and a screw diameter of 44 mm. The chips were obtained by melting, kneading, homogenizing and extruding into a gut-like shape while degassing the vacuum vent part, cooling and solidifying in a water bath and cutting.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 2.
(Comparative Example 6)
10% by weight of polylactic acid P1, 4% by weight of polylactic acid P2, 30% of polyester PA1, 55% by weight of plasticizer S1, 1.0% by weight of organic lubricant SL1, and a screw diameter of 44 mm at a cylinder temperature of 190 ° C. Then, the mixture was melted and kneaded while degassing the vacuum vent part, homogenized, extruded into a gut shape, cooled, solidified in a water bath, and cut to obtain a chip.

Hereinafter, film formation was attempted in the same manner as in Reference Example 1, but the film could not be formed because it could not be pulled out and taken up in a valve shape from an annular die. The results are shown in Table 2.
(Comparative Example 7)
30% by weight of polylactic acid P1, 11% by weight of polylactic acid P3, 30% by weight of polyester PA1, 29% by weight of plasticizer S3, 1.0% by weight of organic lubricant SL1, and a screw diameter with a cylinder temperature of 190 ° C. A chip was obtained by using a 44 mm twin-screw extruder equipped with a vacuum vent, melt-kneading while homogenizing the vacuum vent and extruding it into a gut shape, cooling and solidifying in a water bath and cutting.

Hereinafter, film formation and film evaluation were performed in the same manner as in Reference Example 1, and the results are shown in Table 2.

  The laminated film of the present invention can be used for agricultural films, food packaging films, other packaging films, stretch films, protective films, and the like. Furthermore, depending on the purpose of use, the laminated film of the present invention can be used in combination with other films.

Claims (8)

A polylactic acid resin composition comprising a polylactic acid resin (A), an aliphatic aromatic polyester (B) , a plasticizer (C), and an organic lubricant (D);
In a total of 100% by mass of the polylactic acid resin (A), aliphatic polyester and / or aliphatic aromatic polyester (B), plasticizer (C), and organic lubricant (D), the polylactic acid resin (A) 24 mass% to 64 mass%, aliphatic polyester and / or aliphatic aromatic polyester (B) is 10 mass% to 50 mass%, plasticizer (C) is 5 mass% to 30 mass%, organic lubricant (D) is 0.1 mass% or more and 5 mass% or less,
Melt mass flow rate is Ri der less than 15g / 10min 0.1g / 10min,
A block copolymer in which the plasticizer (C) has a polyether segment and / or a polyester segment and has at least one polylactic acid segment having a number average molecular weight of 1,200 to 10,000 in one molecule. wherein the polymer der Rukoto, chip-like material. The polylactic acid resin composition further contains a pigment (E),
In a total of 100% by mass of the polylactic acid resin (A), aliphatic polyester and / or aliphatic aromatic polyester (B), plasticizer (C), organic lubricant (D), and pigment (E), the polylactic acid resin The resin (A) is 24% by mass or more and 64% by mass or less, the aliphatic polyester and / or the aliphatic aromatic polyester (B) is 10% by mass or more and 50% by mass or less, and the plasticizer (C) is 5% by mass or more and 30% by mass. The chip according to claim 1, wherein the organic lubricant (D) is 0.1 mass% or more and 5 mass% or less, and the pigment (E) is 0.01 mass% or more and 20 mass% or less. State.   The chip-like product according to claim 1 or 2, wherein the aliphatic polyester and / or the aliphatic aromatic polyester (B) is a polybutylene succinate resin.   The chip-like product according to any one of claims 1 to 3, wherein the plasticizer (C) is solid at 20 ° C ± 5 ° C. The chip-like product according to any one of claims 1 to 4 , wherein the crystal melting heat quantity ΔHpl by differential scanning calorimetry is 5 J / g or more and 40 J / g or less. Wherein the moisture content is 1000ppm or less, chip-like product according to any one of claims 1-5. The chip-like product according to any one of claims 1 to 6 , which is used for an inflation film forming method. Films formed by using the chip-like product according to any one of claims 1-7.