JP5484112B2 - Molded body - Google Patents

Description

  The present invention relates to a molded body made of a polylactic acid-based long fiber nonwoven fabric.

  In recent years, synthetic fibers using petroleum as a raw material have a large amount of heat generated during incineration, and therefore need to be reviewed from the viewpoint of protecting the global environment. In contrast, fibers made of aliphatic polyester that biodegrades in nature have been developed and are expected to contribute to environmental protection. Among aliphatic polyesters, polylactic acid polymers that are plant-derived polymers that do not use petroleum as a raw material have a relatively high melting point, and polylactic acid polymers are among biodegradable polymers, Excellent mechanical properties and cost balance. Along with this, development of fibers using these has been carried out, and it is expected to be used in a wide range of fields.

  From such a viewpoint, a long fiber nonwoven fabric using a polylactic acid polymer has been developed (for example, Patent Document 1). However, the long-fiber nonwoven fabric using the polylactic acid polymer has the disadvantages of low elongation at high temperatures and poor moldability.

  In order to compensate for the above disadvantages, a nonwoven fabric composed of two-component core-sheath composite long fibers made of polylactic acid and / or a thermoplastic polymer mainly composed of polylactic acid has been proposed (for example, Patent Document 2). . However, when these non-woven fabrics are molded at 130 ° C. or higher to obtain a molded body, the polylactic acid polymer cannot exhibit good moldability because the elongation at high temperature is not sufficient. was there.

JP 2003-64569 A JP 2000-136478 A

The present invention uses a polylactic acid-based polymer that is a plant-derived polymer, and is a molded article made of a nonwoven fabric that has high elongation at high temperatures, excellent dimensional stability, and excellent moldability. The issue is to provide.

In order to solve the above-mentioned problems, the present inventors have intensively studied to improve the elongation, dimensional stability and moldability at high temperatures in the long-fiber nonwoven fabric using polylactic acid, and as a result, have reached the present invention. . That is, the gist of the present invention is as follows.
(1) Molding of a container shape obtained by preheating a polylactic acid-based long fiber nonwoven fabric comprising composite long fibers including a polylactic acid-based polymer and a polypropylene-based polymer, and press-molding using a predetermined mold The composite form of the composite long fiber is a core-sheath type composite long fiber in which a polylactic acid polymer forms a core and a polypropylene polymer forms a sheath, and the polylactic acid long fiber A molded article characterized in that the elongation at break of the nonwoven fabric at 130 ° C is 150% or more in both the vertical and horizontal directions.
(2) The molded article according to (1), wherein the basis weight of the polylactic acid-based long fiber nonwoven fabric is 10 to 300 g / m ² .
(3) The molded article according to (1) or (2), wherein the dry heat shrinkage at 140 ° C. of the polylactic acid long fiber nonwoven fabric is 10% or less .

  According to the present invention, a polylactic acid polymer that is inferior in extensibility at a high temperature by forming a composite fiber using a polypropylene polymer as a sheath in a nonwoven fabric for obtaining a molded body. Thus, a molded article having excellent elongation at high temperatures and less heat shrinkage can be obtained. In addition, since a biodegradable resin derived from a natural product is used, it can contribute to saving depleted resources such as petroleum.

Hereinafter, the present invention will be described in detail.
The molded product of the present invention comprises a polylactic acid-based long fiber nonwoven fabric. The polylactic acid-based long fiber non-woven fabric is a composite long-fiber non-woven fabric having composite long fibers containing a polypropylene polymer and a polylactic acid-based polymer as constituent fibers.

  The polypropylene-based polymer used in the present invention may be propylene alone or a copolymerized polypropylene whose main repeating unit is a propylene unit. In the case of copolymerized polypropylene, it is preferable that 85 mol% or more of propylene units are contained.

  Examples of the copolymer polypropylene include ethylene random copolymer polypropylene obtained by random copolymerization of ethylene. Moreover, you may use the mixture which made the main component polypropylene and mixed polyethylene etc. in the range with which the objective of this invention is achieved.

From the viewpoint of protecting the global environment, it is preferable to use a polypropylene raw material derived from natural components or obtained by biotechnology.
When the molded body of the present invention is used as a filter, it is preferable to use polypropylene synthesized with a metallocene catalyst because the content of low molecular weight components is reduced and the generation of foreign matters is reduced.

  The melt flow rate (MFR) of the polypropylene polymer is preferably 10 to 80 g / 10 minutes, more preferably 30 to 60 g / 10 minutes, from the viewpoint of spinnability.

  Examples of the polylactic acid polymer used in the present invention include poly (D-lactic acid), poly (L-lactic acid), a copolymer of (D-lactic acid) and (L-lactic acid), and (D-lactic acid) and hydroxy. A copolymer of carboxylic acid, a copolymer of (L-lactic acid) and hydroxycarboxylic acid, a copolymer of (D-lactic acid), (L-lactic acid) and hydroxycarboxylic acid, and a blend thereof. It is done.

  Examples of the hydroxycarboxylic acid include glycolic acid, hydroxybutyric acid, hydroxyvaleric acid, hydroxypentanoic acid, hydroxycaproic acid, and hydroxyoctanoic acid. Of these, hydroxycaproic acid and glycolic acid are preferable from the viewpoint of cost reduction.

  In the present invention, the polylactic acid polymer preferably has a melting point of 150 ° C. or higher, and more preferably 160 ° C. or higher. When the melting point is 150 ° C. or higher, the crystallinity increases and the heat resistance is excellent. Therefore, shrinkage during heat treatment at high temperature does not occur, and heat treatment can be performed stably.

  The melting point of poly (L-lactic acid), which is a homopolymer of polylactic acid, and poly (D-lactic acid) is about 180 ° C. Therefore, when using a copolymer as the polylactic acid polymer instead of a homopolymer, it is necessary to adjust the copolymerization ratio of the monomer components so that the melting point of the copolymer is 150 ° C. or higher.

The copolymerization ratio of (L-lactic acid) and (D-lactic acid) is a molar ratio of (L-lactic acid) / (D-lactic acid) = 5/95 to 0/100, or (L-lactic acid) / ( D-lactic acid) = 95/5 to 100/0 is preferable. When the copolymerization ratio is out of the above range, the melting point of the copolymer becomes less than 150 ° C., and the amorphousness becomes high, so that the heat resistance is inferior and shrinkage occurs during heat treatment at a high temperature.
The MFR of the polylactic acid polymer is preferably 10 to 80 g / 10 minutes, more preferably 20 to 70 g / 10 minutes, from the viewpoint of spinnability.

  Other components can be blended with the polylactic acid polymer. As the component, for example, an aliphatic polyester copolymer (“GSPLa” manufactured by Mitsubishi Chemical Corporation) having an aliphatic diol, an aliphatic dicarboxylic acid and an aliphatic hydroxycarboxylic acid as constituent components, an aliphatic diol and an aromatic Biodegradable aliphatic-copolymerized aromatic polyester copolymers ("Easter Bio GP" manufactured by Novamont, "ECOFLEX" manufactured by BASF) obtained by condensing with carboxylic acid can be used.

  As long as the effects of the present invention are not impaired, the above polypropylene-based polymer and polylactic acid-based polymer have pigments, heat stabilizers, antioxidants, weathering agents, flame retardants, end-capping agents, plasticizers, lubricants, Release agents, antistatic agents, fillers, crystal nucleating agents, and the like may be added. Especially, it is suitable to mix | blend talc as a crystal nucleating agent.

  In the present invention, a composite form of a composite long fiber comprising a polypropylene polymer and a polylactic acid polymer is a core-sheath type in which the polylactic acid polymer forms a core and the polypropylene polymer forms a sheath. It is necessary to be. The reason will be described below.

  Polylactic acid polymers are inferior in high temperature mechanical properties. Therefore, when it exceeds 60 degreeC which is glass transition temperature (Tg), it softens rapidly, and becomes a factor of the physical property fall at the time of the high temperature of the molded object which consists of a nonwoven fabric which uses a polylactic acid-type polymer as a constituent fiber. On the other hand, polypropylene has high mechanical properties even at a high temperature of 130 ° C. Therefore, by placing the polylactic acid polymer in the core part and covering the core part with the sheath part of the polypropylene polymer, compared with a non-woven fabric comprising only the polylactic acid polymer as a constituent fiber, in a high temperature atmosphere A material having a very high elongation at break can be obtained.

  The composite ratio (mass ratio) of the polylactic acid polymer and the polypropylene polymer in the composite long fiber is (polylactic acid polymer) / (polypropylene polymer) = 3/1 to 1/3. preferable. When the ratio of the core part exceeds 3/1, the ratio of the sheath part becomes too small, so that the thermal adhesiveness is inferior, and the shape retention and mechanical performance of the composite long fiber may be inferior. On the other hand, when the ratio of the core portion is less than 1/3, the obtained nonwoven fabric has insufficient mechanical strength.

  In the present invention, the single yarn fineness of the composite continuous fiber is preferably 1 to 15 dtex, more preferably 2 to 12 dtex, and particularly preferably 3 to 8 dtex. If the single yarn fineness is less than 1 dtex, the operability may be impaired in the spinning process. When the single yarn fineness exceeds 15 dtex, the cooling property of the spun yarn is inferior, and the flexibility of the resulting nonwoven fabric may be impaired.

  The polylactic acid-based long fiber nonwoven fabric constituting the molded body of the present invention is configured by a known method using the above-described composite long fiber. The method is not particularly limited, and can be efficiently produced by, for example, a spunbond method. Below, the manufacturing method by a spun bond method is demonstrated.

  First, a polylactic acid polymer and a polypropylene polymer are prepared. Each polymer is weighed individually, and melt-spun through a core-sheath compound spinneret so that the polylactic acid-based polymer forms the core and the polypropylene-based polymer forms the sheath. The yarn is cooled using a conventionally known cooling device such as horizontal spraying or annular spraying, and then pulled down and pulled using a suction device. The pulling speed is preferably 2000 to 5500 m / min. When the pulling speed is less than 2000 m / min, the molecular orientation is not sufficiently promoted in the yarn, and the resulting nonwoven fabric tends to be inferior in dimensional stability and thermal stability. On the other hand, if the pulling speed exceeds 5500 m / min, the spinning stability may be inferior.

  The stretched and thinned composite long fibers are opened with a known spreader, and then spread and deposited on a movable collection surface such as a screen conveyor to form a nonwoven web in which the constituent fibers are randomly deposited. To do. Next, the polylactic acid-based long-fiber nonwoven fabric constituting the molded body of the present invention can be obtained by heat-welding this web with a heat-welding apparatus. Examples of the heat pressure welding apparatus include an emboss roll and a flat roll, and a pair of flat rolls, and a plurality of heat pressure welding apparatuses may be used.

Although the shape of the front-end | tip part of the convex part of embossing becomes the shape of a heat press-contacting part, this shape is not specifically limited. For example, various shapes such as a round shape, an ellipse shape, a rhombus shape, a triangle shape, a T shape, a well shape, a rectangle shape, and a square shape can be adopted. The tip end area of the convex portion is not particularly limited, but may be about 0.1 to 1.0 mm ² .

If necessary, a polylactic acid-based non-woven fabric constituting the molded body of the present invention may be manufactured by applying a binder resin and bonding the constituent fibers together with the binder resin.
When the binder resin is applied, the binder resin may be applied after heat treatment is performed to bond the constituent fibers together. That is, the binder resin is emulsified and dispersed in water to obtain a binder resin liquid, and the binder resin liquid is impregnated with a heat-treated web, or the heat-treated web is applied with a technique such as spraying. For example, a drying method can be employed after the treatment.

From the viewpoint of moldability, the adhesion amount of the binder resin is preferably 20% by mass or less with respect to the fiber mass.
As the binder resin, an aliphatic polyester copolymer (Mitsubishi Chemical Co., Ltd.) containing an aliphatic diol, an aliphatic dicarboxylic acid and an aliphatic hydroxycarboxylic acid as the components blended with the polylactic acid polymer described above. "GSPLa"), biodegradable aliphatic-copolymerized aromatic polyester copolymer obtained by condensing aliphatic diol and aromatic carboxylic acid ("Easter Bio GP" manufactured by Novamont, manufactured by BASF) "ECOFLEX").

  As the binder resin, polyvinyl alcohol, polysaccharides such as starch that are natural products, proteins, chitosan, and the like can be used. In addition, a desired molar ratio can be obtained by combining two or more conventionally used monomers such as methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, acrylonitrile, and styrene. Copolymers copolymerized with can also be employed. Moreover, you may use the bridge | crosslinking type binder resin which bridge | crosslinked these copolymers with crosslinking agents, such as a melamine resin and a phenol resin.

The polylactic acid-based long fiber nonwoven fabric preferably has a basis weight of 10 to 300 g / m ² , more preferably 50 to 200 g / m ² . When the basis weight is less than 10 g / m ² , tearing tends to occur when a molded body is obtained. On the other hand, if the basis weight exceeds 300 g / m ² , the amount of fibers is too large, which is disadvantageous in terms of cost.

  The molded body of the present invention is obtained by molding the polylactic acid-based long fiber nonwoven fabric obtained as described above by a method such as press molding. The molded body may be a container-shaped product or a board-shaped product. In the case of obtaining a container-shaped product by press molding, it is preferable to have a flange part and a container part protruding in a three-dimensional direction from the flange part. In the present invention, a method for obtaining a molded body is not particularly limited. As an example, press molding will be described below.

  When producing a molded body by press molding, the above-mentioned polylactic acid-based long fiber nonwoven fabric is first preheated and then press-molded using a mold or the like. By this preheating, the sheath components of the fibers in contact with each other are melted and softened to form a molded body.

  At the time of this preheating, the sheath portions of the fibers are formed by performing treatment in a range not lower than the softening temperature of the polypropylene copolymer forming the sheath component of the composite long fiber and not higher than the melting temperature of the polypropylene polymer. Fusing well. If the treatment temperature is lower than the softening temperature of the polypropylene polymer, the treatment temperature is too low, and it becomes difficult to fuse the sheath components well together. When the melting temperature of the polypropylene polymer is exceeded, not only the sheath component but also the core component is softened, making it difficult to maintain a desired fiber form. The method for measuring the melting temperature (melting point) will be described in detail in the evaluation methods of the examples.

  In press molding using a mold, it is preferable that the temperature of the mold be equal to or higher than the glass transition temperature of the polylactic acid aggregate forming the core component and lower than the melting point of the polypropylene polymer of the sheath component. . If the temperature of the mold is lower than the glass transition temperature of the polylactic acid polymer, the press moldability tends to deteriorate and it becomes difficult to perform the desired processing. On the other hand, when the mold exceeds the melting point of the polypropylene polymer, the polypropylene polymer melts, so that the press moldability tends to deteriorate.

  In the molded article of the present invention, the elongation at break at 130 ° C. needs to be 150% or more in both the vertical direction and the horizontal direction, and is preferably 200% or more. When the elongation at break at 130 ° C. is 150% or more in both the vertical and horizontal directions, the elongation at high temperature is excellent, and the molding process is easy.

  The polylactic acid-based long fiber nonwoven fabric for obtaining the molded body of the present invention preferably has an elongation at break at room temperature (for example, 25 ° C.) of 20% or more in both the vertical and horizontal directions, and 30% or more. It is preferable that When the elongation at break at normal temperature (for example, 25 ° C.) is 20% or more in both the vertical direction and the horizontal direction, it can be applied to an existing press molding machine.

  In the polylactic acid-based long-fiber nonwoven fabric for obtaining the molded article of the present invention, from the viewpoint of improving the breaking elongation at high temperature, (elongation at breaking at 130 ° C.) / (Elongation at breaking at normal temperature) ) Is preferably 2-7, more preferably 4-7.

  The polylactic acid long fiber nonwoven fabric for obtaining the molded body of the present invention preferably has a tensile strength at 130 ° C. of 5 to 40 N / 5 cm, more preferably 10 to 40 N / 5 cm. Moreover, the polylactic acid-based long fiber nonwoven fabric for obtaining the molded body of the present invention preferably has a tensile strength at room temperature of 40 to 250 N / 5 cm width, and more preferably 50 to 250 N / 5 cm width. When the tensile strength at 130 ° C. and the tensile strength at normal temperature are in the above-described ranges, it can withstand the stress during molding and can be molded satisfactorily.

  The polylactic acid-based long-fiber non-woven fabric for obtaining the molded body of the present invention preferably has a dry heat shrinkage rate at 140 ° C. for 5 minutes of 10% or less in both the vertical and horizontal directions, and preferably 4% or less. Is more preferable and 2% or less is particularly preferable. When the thermal shrinkage rate is 10% or less, the molded body can withstand shrinkage even during preheating and can be molded well.

Hereinafter, the present invention will be described more specifically with reference to examples. The measuring methods used for the evaluation of the resin compositions of Examples and Comparative Examples are as follows.
(1) MFR (g / 10 min)
According to ASTM-D-1238 (E), the temperature was 210 ° C. and the load was 2160 gf.

(2) Melting point (° C)
Using a differential scanning calorimeter (manufactured by Perkin Elma, “DSC-2”), the sample mass is measured at 5 g and the heating rate is 10 ° C./min, and the maximum value of the obtained melting endotherm curve is given. The temperature was taken as the melting point.

(3) Fineness (dtex)
The fiber diameter of any 50 fibers of the nonwoven web was measured with an optical microscope, and the average value obtained by density correction was defined as the fineness.

(4) Weight per unit (g / m ² )
Ten sample pieces having a sample length of 10 cm and a sample width of 5 cm are prepared from a sample in a standard state, the mass (g) of each sample piece is weighed, and the average value of the obtained values is converted per unit area. The basis weight.

(5) Elongation at break at 130 ° C (%)
Ten test pieces having a width of 5 cm and a length of 20 cm were prepared and using a constant speed extension type tensile tester (Orientec Co., Ltd., trade name “UTM-4-1-100”) in an atmosphere of 130 ° C. , Measured according to JIS-L-1906. The conditions at this time were a grip interval of 20 cm and a tensile speed of 20 cm / min. An elongation-load curve was drawn, and an average value of 10 points for elongation at break was defined as elongation at break.

(6) Elongation at break at room temperature (%)
Ten test pieces having a width of 5 cm and a length of 20 cm were prepared, and using a constant speed extension type tensile tester (made by Orientec, trade name “UTM-4-1-100”) at room temperature (25 ° C.). It measured according to JIS-L-1906 under atmosphere. The conditions at this time were a grip interval of 20 cm and a tensile speed of 20 cm / min. An elongation-load curve was drawn, and an average value of 10 points for elongation at break was defined as elongation at break.

(7) Tensile strength at 130 ° C (N / 5cm width)
Ten test pieces having a width of 5 cm and a length of 20 cm were prepared and using a constant speed extension type tensile tester (Orientec Co., Ltd., trade name “UTM-4-1-100”) in an atmosphere of 130 ° C. , Measured according to JIS-L-1906. The conditions at this time were a grip interval of 20 cm and a tensile speed of 20 cm / min. An elongation-load curve was drawn, and an average value of 10 points for the maximum load value (N / 5 cm width) obtained from the obtained elongation-load curve was taken as the tensile strength.

(8) Tensile strength at normal temperature (N / 5cm width)
Ten test pieces each having a width of 5 cm and a length of 20 cm were prepared, and at a normal temperature (25 ° C.) using a constant speed extension type tensile tester (Orientec, trade name “UTM-4-1-100”). It measured according to JIS-L-1906 under atmosphere. The conditions at this time were a grip interval of 20 cm and a tensile speed of 20 cm / min. An elongation-load curve was drawn, and an average value of 10 points for the maximum load value (N / 5 cm width) obtained from the obtained elongation-load curve was taken as the tensile strength.

(9) Dry heat shrinkage (%)
A test piece having a width of 20 cm and a length of 20 cm was cut out from the polylactic acid-based long fiber nonwoven fabric, and the test piece was left to stand in an atmosphere of 140 ° C. for 5 minutes and then heat-treated, and then cooled at room temperature. The dry heat shrinkage rates in the vertical and horizontal directions were determined, respectively.
Vertical heat shrinkage (%)
= {(Vertical dimension of test piece before heat treatment)-(Vertical dimension of test piece after heat treatment)} / (Vertical dimension of test piece before heat treatment) × 100
Horizontal heat shrinkage (%)
= {(Dimension in the horizontal direction of the test piece before heat treatment)-(Dimension in the horizontal direction of the test piece after heat treatment)} / (Dimension in the horizontal direction of the test piece before heat treatment) × 100
(10) A mold for obtaining a molded body having a substantially hemispherical shape (a female mold and a male mold, a female mold having a depth of 65 mm, a diameter of 120 mm, and a male mold that is an air cylinder) The diameter was 120 mm), and a molded body was prepared by subjecting the polylactic acid-based long fiber nonwoven fabric obtained in Examples and Comparative Examples to press molding. At this time, the preheating temperature was 150 ° C., the preheating time was 5 minutes, and the air pressure of the air cylinder was 7 kg / cm ² . Evaluation was made according to the following criteria.
○: The molded body is not torn and is molded well.
X: The tear has arisen in at least one part of a molded object.

Example 1
Polylactic acid (melting point: 174 ° C., MFR: 14 g / 10 min, D-form content: 0.4 mol%) (hereinafter abbreviated as “P1”) was prepared. On the other hand, polypropylene (melting point: 160 ° C., MFR: 60 g / 10 min) (hereinafter abbreviated as “P2”) was prepared.

  In addition, talc is added to the core component P1 melted polymer so that a core-sheath composite cross-section with core / sheath part = 1/1 (mass ratio) with P1 as the core part and P2 as the sheath part. After individually weighing to contain 5 mass%, each was melted at a temperature of 210 ° C. using an individual extruder-type melt extruder, and melt-spun at a single-hole discharge rate of 1.3 g / min. did.

  After cooling the spun yarn with a known cooling device, it is subsequently pulled and thinned at a pulling speed of 2500 m / min into an air football provided below the spinneret, and then opened using a known spreader and moved. It was collected and deposited as a web on a screen conveyor. The single yarn fineness of the deposited composite long fiber was 4.5 dtex.

Subsequently, this web was partially thermocompression-bonded through a partial thermocompression bonding apparatus composed of an embossing roll having a roll temperature of 130 ° C. to obtain a polylactic acid-based long fiber nonwoven fabric having a basis weight of 100 g / m ² for evaluation. Furthermore, a molded body was obtained from the polylactic acid-based long fiber nonwoven fabric and subjected to evaluation.

(Example 2)
Except for the basis weight being 70 g / m ² , a polylactic acid-based long-fiber nonwoven fabric and a molded body were obtained and evaluated in the same manner as in Example 1.

(Example 3)
Except that the basis weight was 50 g / m ² , a polylactic acid long fiber nonwoven fabric and a molded body were obtained and evaluated in the same manner as in Example 1.

(Comparative Example 1)
After preparing P1 and individually weighing so as to contain 0.5% by mass of talc in the molten polymer of P1, it was melted at a temperature of 210 ° C. using an extruder-type melt extruder, and the single-hole discharge amount Melt spinning was performed at 1.7 g / min.
After cooling the spun yarn with a known cooling device, it is subsequently pulverized to an air soccer provided below the spinneret at a traction speed of 5000 m / min, opened using a known spreader, and moved. It was collected and deposited as a web on a screen conveyor. The single yarn fineness of the deposited long fibers was 3.0 dtex.
Subsequently, this web was partially thermocompression-bonded through a partial thermocompression bonding apparatus composed of an embossing roll having a roll temperature of 130 ° C. to obtain a polylactic acid-based long fiber nonwoven fabric having a basis weight of 100 g / m ² . Furthermore, a molded body was obtained from the polylactic acid-based long fiber nonwoven fabric and subjected to evaluation.

(Comparative Example 2)
In addition, talc is added to the melt polymer of P1 of the sheath component so that the core-sheath composite cross section with core portion / sheath portion = 1/1 (mass ratio) with P2 as the core portion and P1 as the sheath portion. After individually weighing to contain 5 mass%, each was melted at a temperature of 210 ° C. using an individual extruder-type melt extruder, and melt-spun at a single-hole discharge rate of 1.3 g / min. did.

  After cooling the spun yarn with a known cooling device, it is subsequently pulled and thinned at a pulling speed of 4500 m / min into an air soccer provided below the spinneret, and opened using a known opening device and moved. It was collected and deposited as a web on a screen conveyor. The single yarn fineness of the deposited composite long fiber was 2.8 dtex.

Subsequently, this web was partially thermocompression-bonded through a partial thermocompression bonding apparatus composed of an embossing roll having a roll temperature of 130 ° C. to obtain a polylactic acid-based long fiber nonwoven fabric having a basis weight of 100 g / m ² . Furthermore, a molded body was obtained from the polylactic acid-based long fiber nonwoven fabric and subjected to evaluation.

  The evaluation results of Examples 1 to 3 and Comparative Examples 1 and 2 are shown in Table 1.

実施例１〜３で得られた長繊維不織布は、タテ方向、ヨコ方向ともに、高温雰囲気下での破断時の伸度が常温雰囲気下の伸度と比較して顕著に向上していた。また、１４０℃における乾熱収縮率も小さいものであった。そのため、高温時における成型性に優れた成型体を得ることができた。

In the long fiber nonwoven fabrics obtained in Examples 1 to 3, the elongation at break in a high temperature atmosphere was significantly improved in both the vertical and horizontal directions compared to the elongation in a normal temperature atmosphere. The dry heat shrinkage at 140 ° C. was also small. Therefore, it was possible to obtain a molded body having excellent moldability at high temperatures.

In Comparative Example 1, the obtained molded body had a low elongation at break in a high temperature atmosphere in both the vertical and horizontal directions. Therefore, when it was set as the molded body, it was inferior in moldability at high temperature.
In Comparative Example 2, since the elongation at room temperature was low and the followability to the mold was poor, the nonwoven fabric was not able to withstand the stress with respect to elongation during molding, and a molded body was not obtained.

Claims (3)

This is a container-shaped molded body obtained by preheating a polylactic acid-based long-fiber nonwoven fabric comprising composite long fibers containing a polylactic acid-based polymer and a polypropylene-based polymer as a constituent fiber, and press-molding using a predetermined mold. And
The composite form of the composite long fiber is a core-sheath type composite continuous fiber in which a polylactic acid-based polymer forms a core part and a polypropylene-based polymer forms a sheath part. The molded body is characterized by having an elongation at break of 150% or more in both the vertical and horizontal directions. Molded body according to claim 1, wherein the basis weight of the polylactic acid-based long-fiber nonwoven fabric is characterized in that it is a 10 to 300 g / m ^2. The molded article according to claim 1 or 2, wherein the polylactic acid-based long fiber nonwoven fabric has a dry heat shrinkage at 140 ° C of 10% or less .