JP2021088067A - Production device and method for resin composition for melt spinning, and melt spinning device - Google Patents

Abstract

To provide a production device for a resin composition for melt spinning for producing a fiber combining high handleability and high continuous feedability and having a finer size, and a production method therefor.SOLUTION: A production device produces a resin composition for melt spinning made of a filament. The production device comprises an extrusion molding part for subjecting a resin composition having a melt viscosity of 250 Pa s or lower at 200°C and at a shear viscosity of 0.1 s-1 to extrusion molding into a filament shape and a carrier part for receiving the extrusion-molded article and carrying the same to a next step. A distance between a discharge port of a resin composition and the carrier part is 50 mm or lower and the diameter of the discharge port is 1 to 50 mm. There is also provided a method for producing a resin composition for melt spinning made of a filament by using the production device.SELECTED DRAWING: Figure 1

Description

The present invention relates to an apparatus for producing a resin composition for melt spinning, a method for producing the same, and a melt spinning apparatus.

The melt spinning method is a technique capable of producing a fiber sheet having fine-diameter fibers easily and with high productivity by discharging a molten liquid of a raw material resin in the presence of a gas flow or an electric field.

Patent Document 1 discloses a strand manufacturing apparatus having an extrusion molding means for melt-kneading a resin composition and extrusion molding into a strand shape, and a cooling solidification means for cooling and solidifying the extrusion-molded strand-shaped resin composition. ing. It is also disclosed in the same document that this strand can be further thermally melted and used in the production of a three-dimensional model.

Patent Document 2 describes a step of extracting a molten thermoplastic resin from a die in a strand shape, a step of cooling the extracted strand-shaped resin with a refrigerant, and cutting the cooled strand-shaped resin. A method for producing a resin pellet including a step of obtaining the resin pellet is disclosed. The document also discloses that the pellets can be used to form fibers.

International Publication No. 2017/149896 Pamphlet International Publication No. 2018/216550 Pamphlet

By the way, in producing fibers and fiber sheets with high production efficiency by the melt spinning method, a method for improving the handleability and continuous supply of raw materials is desired. However, the strands and resin pellets described in Patent Documents 1 and 2 improve the handleability and continuous supply of raw materials when they are used as raw material resins and supplied to the fiber manufacturing process to industrially produce fibers. No consideration has been given to letting them do it.

Therefore, an object of the present invention is to provide an apparatus for producing a resin composition for melt spinning, a method for producing the same, and a melt spinning apparatus capable of eliminating the drawbacks of the prior art.

In the present invention, an extrusion-molded part for extruding a resin composition having a melt viscosity of 250 Pa · s or less at 200 ° C. and a shear rate of 0.1 s- ^{1 into filaments, and an extrusion-molded molded product are received and the next step is performed.} Equipped with a transport unit to transport to
Provided is an apparatus for producing a resin composition for melt spinning, which comprises a filament in which the distance between the discharge port of the resin composition and the transport portion is 50 mm or less and the diameter of the discharge port is 1 mm or more and 50 mm or less. Is.

Further, the present invention is a method for producing a resin composition for melt spinning, which comprises a filament using the above-mentioned production apparatus.
A melt of a resin composition having a melt viscosity of 250 Pa · s or less at 200 ° C. and a shear rate of 0.1 s- ¹ is extruded from the discharge port having a diameter of 1 mm or more and 50 mm or less to form a filament, and the molded product is formed. The present invention provides a method for producing a resin composition for melt spinning, which comprises a step of cooling while transporting the filament.

Further, in the present invention, the manufacturing apparatus, the supply port to which the resin composition for melt spinning produced by the manufacturing apparatus is supplied, and the resin composition supplied from the supply port are not kneaded. A heating unit for melting, a nozzle for directly communicating with the heating unit and discharging the melted resin composition, and a gas flow injection unit for transporting the discharged resin composition to a gas flow. Provided is a melt spinning apparatus provided.

According to the present invention, it is possible to obtain a resin composition for melt spinning, which comprises a filament having high handleability and high continuous supply property, and for producing a fiber having a smaller diameter. Further, according to the present invention, finer diameter fibers can be produced with high production efficiency by using the resin composition for melt spinning.

FIG. 1 is a schematic view showing an embodiment of the filament manufacturing apparatus of the present invention. FIG. 2 is a schematic view showing another embodiment of the filament manufacturing apparatus of the present invention. 3A and 3B are schematic cross-sectional views showing still another embodiment of the filament manufacturing apparatus of the present invention. FIG. 4 is a schematic view showing an embodiment of a melt spinning apparatus including the filament manufacturing apparatus shown in FIG. 3 (a). 5 (a) and 5 (b) are enlarged schematic views showing the arrangement positions of the discharge port and the transport portion. FIG. 6 is a schematic perspective view showing an embodiment of the melt spinning apparatus of the present invention. 7 (a) and 7 (b) are schematic cross-sectional views showing an embodiment of a spinning unit in the melt spinning apparatus of the present invention.

Hereinafter, the present invention will be described based on the preferred embodiment with reference to the drawings. 1 to 5 show each embodiment of a manufacturing apparatus 10 for manufacturing a resin composition for melt spinning made of filaments. The manufacturing apparatus 10 shown in FIG. 1 is roughly classified into an extrusion molding unit 20 and a transport unit 30.

The extrusion molding unit 20 includes a cylinder 21, a discharge unit 22, and a hopper 29 for supplying the resin composition. In the cylinder 21, the resin composition supplied from the hopper 29 can be heated and melted in the cylinder 21 to obtain a melt L of the resin composition. The molten liquid can be supplied by pushing out the molten liquid in the direction of the discharge portion 22, which will be described later, by a screw (not shown) provided in the cylinder 21. As the resin composition supplied from the hopper 29, a resin composition having a melt viscosity of 250 Pa · s or less at ^{200 ° C. and a shear rate of 0.1 s-1 is used.}

The discharge unit 22 is a member that extrudes the molten liquid of the resin composition into a filament shape, and includes a discharge base portion 23 and a discharge port 24. The cylinder 21, the discharge base 23, and the discharge port 24 communicate with each other, and the molten liquid in the cylinder 21 can be continuously pushed out from the discharge port 24 via the inside of the discharge base 23. A gear pump (not shown) is installed in the discharge base 23 so that the melted liquid of the resin composition can be discharged in a fixed amount.

The transport unit 30 transports the filament-shaped molded product S extruded from the discharge port 24 to the next step. The transport unit 30 is provided at a position substantially opposite to the discharge port 24, and is composed of one or more of a conveyor and a roll. The transport unit 30 shown in FIGS. 1 and 2 is in the form of a belt conveyor in which an endless belt is arranged so as to orbit in one direction, and receives the molded product S directly without interposing other members. It can be transported in direct contact with the belt conveyor. The transport units 30 shown in FIGS. 3 (a) and 3 (b) and FIG. 4 are in the form of rotatable transport rolls 36 and 37.

The resin composition introduced into the present manufacturing apparatus has a relatively low melt viscosity and high fluidity of the molten liquid. Therefore, when extruding from the discharge port 24 into a filament, the discharge port 24 The discharged molded product may unintentionally adhere to a member other than the transport portion 30, or the molded product may be stretched into an unintended shape, resulting in a uniform and continuous filament. May not be formed. In order to solve such a problem, the manufacturing apparatus 10 sets the distance between the discharge port 24 in the extrusion molding unit 20 and the transport unit 30 within a predetermined range, and sets the diameter of the discharge port 24 within a predetermined range. One of the features is to do.

Specifically, the distance D1 (see FIGS. 5A and 5B) between the discharge port 24 in the extrusion molding unit 20 and the transport unit 30 is preferably 50 mm or less, more preferably 30 mm or less, still more preferably 15 mm. It is less than or equal to, preferably 3 mm or more is realistic. The distance D1 between the discharge port 24 and the transport unit 30 is the shortest distance from the end of the discharge port 24 to the intersection of the virtual extension line extending along the axial direction of the discharge port 24 and the surface of the transport unit 30. Further, as shown in FIG. 3B described later, when the molded product S discharged from the discharge port 24 is directly immersed in the liquid W without passing through other members, the distance D1 is set between the discharge port 24 and the liquid W. The shortest distance from the liquid level of.

The diameter of the discharge port 24 is preferably 1 mm or more, more preferably 3 mm or more, further preferably 5 mm or more, preferably 50 mm or less, more preferably 40 mm or less, still more preferably 30 mm or less. The shape of the discharge port 24 is preferably a perfect circle. By making the manufacturing apparatus such a size, it is possible to form a filament of a resin composition having both high handleability and high continuous supply.

The filament-shaped molded product S extruded from the discharge port may not be sufficiently cooled and solidified after extrusion molding. From the viewpoint of reliably maintaining the filament shape of the extruded molded product S, it is preferable to provide means for cooling the molded product S while transporting it to the unidirectional MD. As the cooling means, for example, the transport path of the transport unit 30 may be formed long along the transport direction to allow natural cooling, and the transport unit 30 is in contact with the refrigerant or the cooling device (not shown). Therefore, the transport unit 30 itself may be cooled, or the cooling unit 40 may be further provided on the downstream side of the transport unit 30. When the cooling unit 40 is provided, the cooling unit 40 houses a conveyor and a roll that are cooled in contact with a refrigerant or a cooling device (not shown), a cooling gas supply unit that can blow a cooling gas flow, and a cooling gas. It is also preferable that the inside thereof is composed of at least one gas tank through which the molded product S can pass, and at least one liquid tank in which the cooling liquid is housed and the molded product S can come into contact with the liquid. As the cooling gas, for example, air can be used, and as the cooling liquid, a liquid that does not affect the composition of the molded product S, such as water, can be used.

The manufacturing apparatus 10 shown in FIG. 1 is provided with a cooling unit 40 having a liquid tank 41 and a transport roll 42 on the downstream side of the transport unit 30 in the transport direction. The conveyed molded product S can be cooled by bringing it into contact with the liquid W in the liquid tank 41.
Further, the manufacturing apparatus 10 shown in FIG. 2 is provided with a cooling gas supply unit 45 above the transport unit 30 and downstream in the transport direction, and can cool the molded product S by bringing the gas flow A into contact with the molded product S.

Further, in the manufacturing apparatus 10 shown in FIGS. 3 and 4, the transport roll 36 constituting the transport unit 30 is arranged in a state of being partially immersed in the liquid W contained in the liquid tank 41, and the liquid of the transport roll 36 is arranged. The molded product S discharged from the discharge port 24 is directly received on the peripheral surface not immersed in W, and the molded product S adhering to the peripheral surface is brought into contact with the liquid W and cooled by the rotation of the transport roll 36. This makes it easier to maintain the shape of the molded product S at the time of molding, and makes it possible to more easily produce a filament having high storage stability and handleability.
Further, in the manufacturing apparatus 10 shown in FIG. 3B, the transport rolls 36 constituting the transport unit 30 are arranged in a state of being completely immersed in the liquid W contained in the liquid tank 41, and discharged from the discharge port 24. The molded product S is brought into direct contact with the liquid W to be cooled, and the cooled molded product S is adhered to the peripheral surface of the transport roll 36 and transported.
As described above, the transport unit 30 and the cooling unit 40 may be arranged separately or integrally.

From the viewpoint of increasing the cooling efficiency of the molded product S to form a filament of the resin composition having both high handleability and high continuous supply property, the melt of the resin composition with respect to the temperature in the transport unit 30 or the cooling unit 40. The temperature ratio is preferably 1.2 times or more, more preferably 1.3 times or more, further preferably 1.4 times or more, preferably 2.1 times or less, more preferably 1.9 times or more in terms of absolute temperature. It is doubled or less, more preferably 1.7 times or less. The temperature of the melt of the resin composition is the temperature of the melt at the discharge port 24. Such a temperature ratio range makes the degree of crystallization of the resin depending on the cooling rate appropriate, and can suppress the occurrence of voids and cracks in the filament, and is flexible and applicable to the melt spinning method. It is particularly advantageous in obtaining a filament having both strength and strength.

From the viewpoint of increasing the cooling efficiency of the molded product S and forming a filament having both flexibility and strength, the cooling temperature in the transport unit 30 or the cooling unit 40 is preferably −40 ° C. or higher, more preferably 0 ° C. or higher. Above, it is more preferably 5 ° C. or higher, preferably 90 ° C. or lower, more preferably 80 ° C. or lower, still more preferably 70 ° C. or lower. From the same viewpoint, it is also preferable that the cooling unit 40 is configured to cool the molded product S by using a gas or liquid having the above-mentioned temperature range.

The method for producing a resin composition composed of filaments using the above-mentioned production apparatus 10 is as follows. First, a resin composition having a melt viscosity of 250 Pa · s or less at 200 ° C. and a shear rate of 0.1 s- ¹ is supplied into the cylinder 21 of the extrusion molding unit 20 and heated and melted. And. As described later, the constituent component of the resin composition preferably contains one or more of a polyolefin resin and a polyester resin, and at least one of an elastomer, a plasticizer, a modifier, a decomposition inhibitor, and a charge modifier. It is also preferable to include an additive that is.

Next, the melt is supplied toward the discharge port 24, and the melt is continuously extruded from the discharge port 24 in the form of a filament to form a filament-shaped molded product S. At this time, the diameter of the discharge port 24 is preferably 1 mm or more and 50 mm or less as described above. Subsequently, the molded product S is directly received by the transport unit 30, and is cooled while being transported downstream.

From the viewpoint of applying an appropriate external force before the molded product S is sufficiently cooled and solidified to facilitate the formation of filaments having a uniform surface condition and shape, the molded product with respect to the extrusion speed V1 of the molten liquid from the discharge port 24. The ratio (V2 / V1) of the transport speed V2 of S is preferably 1 or more, more preferably 3 or more, further preferably 5 or more, preferably 50 or less, more preferably 35 or less, still more preferably 25 or less. ..

From the same viewpoint, the extrusion speed V1 of the molten liquid from the discharge port 24 is preferably 0.1 m / min or more, more preferably 0.15 m / min or more, still more preferably 0.2 m / min or more, and is preferable. Is 20 m / min or less, more preferably 10 m / min or less, still more preferably 5 m / min or less. The extrusion speed of the molten liquid from the discharge port 24 can be appropriately changed by adjusting, for example, the supply speed of the molten liquid from the cylinder 21.

From the same viewpoint, the transport speed V2 of the molded product S is preferably 0.2 m / min or more, more preferably 1.0 m / min or more, still more preferably 1.5 m / min or more, and preferably 200 m / min or more. It is min or less, more preferably 100 m / min or less, still more preferably 50 m / min or less. The transport speed of the molded product S is appropriately changed by, for example, adjusting the moving speed of the conveyor or the rotation speed of the roll in the transport unit 30, or adjusting the winding speed of the filament in the winding unit 50 described later. be able to.

When the extrusion-molded molded product S is cooled while being transported to the one-way MD, as described above, the molded product S may be naturally cooled while being transported by the transport unit 30, and the molded product S is transported by the transport unit 30. While doing so, the molded product S may be cooled by bringing a gas or liquid into contact with the molded product S, or the molded product S may be cooled while being conveyed in contact with the cooled transport unit 30, and the cooling unit 40 may be cooled. Further, it may be further arranged to cool the molded product S while passing it through the cooling unit 40.

Through the above steps, a resin composition F composed of filaments (hereinafter, also simply referred to as “filament F”) can be obtained.

The obtained filament F can be wound by the winding unit 50 and stored in the form of a wound body in which the filament F is wound, for example, as shown in FIGS. 1 to 3. This wound body can be used to continuously or intermittently supply the raw material using the filament as a raw material in the process of producing ultrafine fibers described later. Instead, as shown in FIG. 4, as an embodiment of the melt spinning apparatus 100 provided with the above-mentioned manufacturing apparatus 10, the filament F produced by the manufacturing apparatus 10 is directly supplied to the melt spinning apparatus 100 to produce fibers. You may. Details of the melt spinning apparatus 100 will be described later.

The filament F produced by the manufacturing apparatus 10 is a resin composition composed of a solid or hollow filament having a predetermined melt viscosity and a predetermined tensile strength. This resin composition is suitably used for melt spinning applications such as the melt blow method and the molten electric field spinning method as a molten liquid obtained by heating and melting the resin composition.

The resin composition has a melt viscosity of preferably 250 Pa · s or less, more preferably 150 Pa · s or less, still more preferably 50 Pa · s or less at a temperature of 200 ° C. and a shear rate of 0.1 s- ^{1, and is preferably 0.} It is 05 Pa · s or more, more preferably 0.1 Pa · s or more, still more preferably 0.5 Pa · s or more. When the melt viscosity is in such a range, when the resin composition is subjected to melt spinning, the discharge efficiency of the melt liquid can be increased and the fiber formation efficiency can be increased. The melt viscosity of the resin composition can be appropriately changed by, for example, changing the molecular weight of the resin used or adding a plasticizer, a modifier, or the like described later.

The melt viscosity of the resin composition is, for example, a sample obtained by using a known extruder at a temperature of 200 ° C. using a viscoelasticity measuring device (model number MCR302) manufactured by Anton Pearl Japan Co., Ltd. It can be measured under the condition of shear rate 0.1s ^-1.

The resin composition has a tensile strength of preferably 10 MPa or more, more preferably 12 MPa or more, still more preferably 15 MPa or more. When the tensile strength is in such a range, the resin composition can be easily handled, and can be easily continuously supplied as a raw material for melt spinning, so that the fiber production efficiency can be improved. The tensile strength of the resin composition can be adjusted, for example, by changing the type of resin used, changing the cooling temperature or speed to change the crystal state of the obtained resin composition, or using a plasticizer or modification described later. It can be appropriately changed by a method such as adding an agent or the like.

The tensile strength of the resin composition is measured using, for example, a tensile tester (AG-X plus manufactured by Shimadzu Corporation). The test speed was 50 mm / min, the distance between chucks was 80 mm, the test was performed using a resin composition composed of filaments having a length of 120 mm, and the tensile test was performed along the filament length direction until fracture. The maximum test force and the chuck movement distance were measured. This measurement was performed 3 times. The tensile strength and breaking strain shall be the arithmetic mean values of the values calculated from each of the three measured values based on the following formula. In the following formula, R is a filament diameter described later.
Tensile strength [MPa] = (maximum test force ^{[N]) / (πR 2} /4)
Breaking strain [%] = (chuck moving distance [mm] / inter-chuck distance [mm]) x 100

As described above, the resin composition is composed of filaments. The filament diameter R of the resin composition, that is, the diameter of the cross section in the direction orthogonal to the length direction of the filament is preferably 1 mm or more, more preferably 1.3 mm or more, still more preferably 1.5 mm or more, and preferably 1.5 mm or more. It is 30 mm or less, more preferably 20 mm or less, still more preferably 15 mm or less.

A filament is generally an infinite length fiber that has substantially no end, but in the present specification, it is interpreted in a substantially broader sense, and the ratio of the length to the cross-sectional diameter is preferable. 20 or more, more preferably 50 or more, still more preferably 100 or more fibers are included in the filaments herein. Since the filament has a substantially infinite length, there is no upper limit to the ratio, but 1,000,000 or less is realistic.

The length of the filament is infinite as described above, but if the length is preferably 10000 m, more preferably 5000 m or less, preferably 50 mm or more, still more preferably 100 mm or more, in the present specification. Included in the filament. Such filaments can be obtained, for example, by cutting infinite length filaments to a predetermined length. As described above, when the filament diameter, the filament length, and the filament length / diameter ratio are within the above ranges, the filament can be more easily handled during storage and spinning.

The cross-sectional diameter of the filament can be measured, for example, as follows. That is, for one filament having a length of more than 50 cm, the length in the direction orthogonal to the length direction of the filament was measured at 10 points along the length direction of the filament at 5 cm intervals using a caliper. The arithmetic mean value of the measured values is taken as the cross-sectional diameter. When the filament cross section is not a perfect circle, the major axis and the minor axis are measured at each measurement point using a nogisu, and the arithmetic average value of the major axis and the minor axis at each measurement point is used as the measurement value at each measurement point. The arithmetic average value of the measured values at all measurement points is taken as the cross-sectional diameter.

The resin composition composed of filaments preferably contains a thermoplastic resin as a main component thereof. This thermoplastic resin has a fiber-forming property and a melting point in melt spinning. A resin having a "melting point" means that, in the differential scanning calorimetry (DSC method), when the resin to be measured is heated, the phase changes from solid to liquid before the resin is thermally decomposed. It is a resin that shows a heat absorption peak due to.

Examples of such thermoplastic resins include polyolefin resins such as polyethylene, polypropylene, ethylene-α-olefin copolymer, and ethylene-propylene copolymer; polyethylene terephthalate, polybutylene terephthalate, liquid crystal polymer, polylactic acid, and lactic acid-hydroxycarboxylic acid copolymer. Polylactic acid-based resins such as polyester resins; polyamide resins; vinyl-based polymers such as polyvinyl chloride, polyvinylidene chloride and polystyrene; acrylic polymers such as polyacrylic acid, polyacrylic acid esters, polymethacrylic acid and polymethacrylic acid esters. Nylon-based polymers such as nylon 6 and nylon 66, polyvinyl acetate, polyvinyl acetate-ethylene copolymer; and the like. As these resins, commercially available products may be used, commercially available products may be subjected to post-treatment such as hydrolysis, or synthetic products may be used. These resins may be used alone or in combination of two or more.

Of these, from the viewpoint of increasing mechanical properties such as strength and flexibility when made into a filament, and from the viewpoint of increasing the versatility of the use of the fiber when the fiber is manufactured using the filament. The resin composition preferably contains one or more of a polyolefin resin and a polyester resin, and more preferably contains a polypropylene or polylactic acid-based resin. The lactic acid constituting the repeating unit of the polylactic acid-based resin may be either an L-form or a D-form optical isomer.

The content of the thermoplastic resin contained in the resin composition is preferably 70 parts by mass or more, more preferably 75 parts by mass or more, still more preferably 80 parts by mass or more, and preferably 80 parts by mass or more, based on 100 parts by mass of the resin composition. Is 100 parts by mass or less, more preferably 98 parts by mass or less, still more preferably 95 parts by mass or less.

The resin composition may also contain an additive which is at least one of an elastomer, a plasticizer, a modifier, a decomposition inhibitor and a charge modifier, depending on the use of melt spinning, from the viewpoint of increasing the efficiency of fiber production. preferable. These additives can be used alone or in combination of two or more.
The elastomer is one that improves the elasticity of the resin composition to increase the toughness, and for example, an olefin-based elastomer, a styrene-based elastomer, an ester-based elastomer, a urethane-based elastomer, or the like can be used.
The plasticizer is modified so as to increase the flexibility of the resin composition, change the glass transition temperature (Tg), or increase the fluidity of the melt of the resin composition, for example, polyethylene glycol (PEG). ), Glycerin, glycerin fatty acid ester, glycerin acetate, phosphoric acid ester, cellulose derivative (hydroxypropyl cellulose: HPC or methyl cellulose: MC), lactone, carbamate ester, phthalic acid and the like can be used.
The modifier is a modifier that enhances the flexibility of the resin composition or enhances the fluidity of the resin composition when it is made into a melt. For example, a low stereoregular polyolefin (manufactured by Idemitsu Kosan Co., Ltd.) Molding modifier L-MODU) and the like can be used.

The decomposition inhibitor suppresses the decomposition of the resin composition and the decrease in molecular weight when the melted liquid of the resin composition is subjected to melt spinning such as a melt blow method and a molten electrospinning method. Examples thereof include carbodiimide compounds such as carbodiimide compounds and polycarbodiimide compounds. These additives can be used alone or in combination of two or more.

Examples of the monocarbodiimide compound include diphenylcarbodiimide, di-2,6-dimethylphenylcarbodiimide, di-2,6-diethylphenylcarbodiimide, di-2,6-diisopropylphenylcarbodiimide, and di-2,6-di-tert. -Butylphenylcarbodiimide, di-o-tolylcarbodiimide, di-p-tolylcarbodiimide, di-2,4,6-trimethylphenylcarbodiimide, di-2,4,6-triisopropylphenylcarbodiimide, and di-2,4 , 6-Aromatic monocarbodiimide compounds such as triisobutylphenylcarbodiimide; alicyclic monocarbodiimide compounds such as di-cyclohexylcarbodiimide and di-cyclohexylmethanecarbodiimide; aliphatic products such as di-isopropylcarbodiimide and di-octadecylcarbodiimide. Examples include carbodiimide compounds.
Examples of the polycarbodiimide compound include poly (4,4'-diphenylmethanecarbodiimide), poly (p-phenylene carbodiimide), poly (m-phenylene carbodiimide), poly (diisopropylphenylcarbodiimide), and poly (triisopropylphenyl). Aromatic polycarbodiimides such as carbodiimides; alicyclic polycarbodiimides such as poly (dicyclohexylmethanecarbodiimides).

The charge adjuster modifies the melt of the resin composition so as to develop a high charge amount when the melt is subjected to the melt electrospinning method. For example, Zn stearate, Mg stearate, and stearer are used. Salts of higher fatty acids such as Li acid, Zn laurate, Zn lysinolate and metals; alkyl sulfates, alkyl ether sulfates, alkyl sulfonates, alkylbenzene sulfonates, alkylnaphthalene sulfonates, olefin sulfonates, Sulfates and sulfonates such as N-alkyl-N-acylaminoalkyl sulfonates and alkane sulfonates can be used. These additives can be used alone or in combination of two or more.

From the viewpoint of increasing the production efficiency of the small-diameter fiber, the content of the additive in the resin composition is preferably 1 part by mass or more and 3 parts by mass or more with respect to 100 parts by mass of the resin composition. Is more preferably 5 parts by mass or more, more preferably 40 parts by mass or less, further preferably 30 parts by mass or less, and further preferably 20 parts by mass or less.

According to the above-mentioned resin composition, since it has a predetermined melt viscosity, when it is used as a melt for melt spinning, the amount and speed of discharge of the melt to the outside can be increased, and the melt can be discharged. Since the drawing efficiency of the fiber can be increased, fine-diameter fibers can be produced with high production efficiency. Further, since the resin composition is composed of a filament having a predetermined tensile strength, unintentional breakage, cracking, buckling, and fracture are reduced when the filament is stored or when the filament is subjected to melt spinning. It is possible to improve the storage stability and handleability of the resin composition composed of filaments. According to a preferred embodiment of the resin composition composed of filaments, the flexibility is high, the handling during storage and spinning can be further facilitated, and the production efficiency of fibers can be further improved. In addition to this, even when using a polylactic acid-based resin, which was difficult to apply to melt spinning with conventional techniques, while preventing deterioration of the raw material due to heat and hydrolysis during melting. It is possible to efficiently produce fibers with a small diameter.

In any case, the resin composition composed of this filament can be used as it is as a raw material when producing fibers by the melt spinning method, so that thermal deterioration of the raw material at the time of melting is reduced and equipment is provided. It can be applied to existing equipment without causing problems in terms of equipment such as expansion of the equipment. In addition, since the resin composition composed of filaments has both flexibility and strength, it reduces unintentional breakage, cracking, buckling, and breakage during storage and melt spinning, and has high handleability. Become. Further, since the filament produced by the above-mentioned suitable production method is formed by the molten liquid continuously extruded from the discharge port 24, one continuous uniform filament can be produced. As a result, when the fiber is produced using the melt spinning apparatus 100 described later using the filament as a raw material, the raw material can be continuously and stably supplied, and the fiber can be produced stably.

Subsequently, the melt spinning apparatus 100 will be described with reference to FIGS. 4 and 6. The melt spinning device 100 can be suitably used when producing fibers by a melt spinning method, particularly a melt blowing method or a molten electric field spinning method. The melt blow method and the molten electric field spinning method are spinning methods particularly suitable for producing ultrafine fibers among the melt spinning methods. The melt spinning device 100 may be a stationary type that is preferably used when placed on a floor, a shelf, a desk, or the like, has dimensions that can be manually gripped, and is suitable for being manually gripped. It may be a handy type used for.

The melt spinning apparatus 100 shown in FIG. 4 is directly connected to the supply port 110 to which the raw material F is supplied, the heating unit 120 for melting the raw material F supplied from the supply port 110 without applying kneading force, and the heating unit 120. It is provided with a nozzle 130 that communicates and discharges a molten raw material. The raw material F supplied in the melt spinning apparatus 100 is preferably a raw material containing a thermoplastic resin, and in particular, the resin composition F composed of the above-mentioned filament is preferably used. In addition to this, at least the gas flow injection unit 140 for transporting the raw material F discharged from the nozzle 130 to the gas flow and the electrode 160 for forming an electric field for charging the raw material F discharged from the nozzle 130. It is more preferable to have one.

The melt spinning apparatus 100 includes a supply port 110 to which the raw material F is supplied. The melt spinning apparatus 100 shown in FIG. 4 is provided with a drive unit 111 having an electric motor (not shown) such as a stepping motor in the vicinity of the supply port 110, and supplies the raw material F by the rotation of the electric motor. It can be continuously supplied to the 110 side at a predetermined speed. The electric motor in the drive unit 111 is connected to a gear 113 made of spur gears via a shaft 112 so that the rotation of the electric motor can be transmitted to the gear 113. A bearing 115 that can be rotated by the rotation of the gear 113 is provided on the side facing the gear 113, and is arranged in a state in which the axial direction of the gear 113 and the axial direction of the bearing 115 are aligned with each other. By supplying the raw material F between the gear 113 and the bearing 115, the raw material F is conveyed in the unidirectional MD along the rotation direction of the gear 113 and supplied to the supply port 110. The drive unit 111 is fixed and supported by a support member (not shown) provided on the supply port 110 or the floor or the like.

The melt spinning device 100 includes a heating unit 120 that melts the raw material F supplied from the supply port 110. The heating unit 120 communicates with the supply port 110. The heating unit 120 is heated by a heating means (not shown) such as a heater, and by supplying the raw material F into the heating unit 120, a molten liquid obtained by melting the raw material F without applying kneading force is obtained. be able to. "Without applying kneading force" means that no shearing force is applied to the raw material to be melted. That is, the heating unit 120 does not have a member or means for applying a shearing force to the raw material, such as a screw or a stirring blade, inside the heating unit 120. The molten liquid melted by the heating unit 120 moves to the nozzle 130 side while being pushed out according to the supply speed of the raw material F supplied from the supply port 110.

The heating temperature in the heating unit 120 can be appropriately changed according to the physical properties of the supplied raw material F, but is preferably a temperature equal to or higher than the solidification temperature of the raw material. For example, when polypropylene (melting point: 160 ° C.) is contained as a raw material, the heating temperature in the heating unit 120 is preferably 180 ° C. or higher, more preferably 190 ° C. or higher, preferably 280 ° C. or lower, still more preferably 260 ° C. or lower. Is. Further, for example, when polylactic acid (melting point: 160 ° C.) is contained as a raw material, the heating temperature in the heating unit 120 is preferably 180 ° C. or higher, more preferably 190 ° C. or higher, preferably 280 ° C. or lower, still more preferably. It is 260 ° C. or lower.

The melt spinning device 100 has a hollow nozzle 130 that directly communicates with the heating unit 120 and discharges the molten raw material, and a gas flow injection unit 140 for transporting the molten raw material discharged from the nozzle 130 to a gas flow. I have. The melt spinning apparatus 100 shown in FIGS. 4 and 6 is in the form of a spinning unit 200 including a nozzle 130 and a gas flow injection unit 140. The upper part of the spinning unit 200 is provided with a gas flow generating unit 150 that supplies a heated gas flow to the gas flow injection unit 140.

7 (a) and 7 (b) schematically show a cross section of the spinning unit 200 in the melt spinning apparatus 100. The spinning unit 200 shown in FIG. 7A is preferably used in the melt blowing method among the melt spinning methods. The nozzle 130 shown in FIG. 7A is arranged in the central region of the spinning unit and directly communicates with the heating unit 120. That is, the supply port 110, the heating unit 120, and the nozzle 130 are all in direct communication with each other. The nozzle 130 can discharge the molten liquid of the raw material melted in the heating unit 120 from the tip of the nozzle 130 to the outside via the resin supply path 131 communicating with the heating unit 120 and the nozzle 130. Since the molten liquid discharged from the nozzle 130 is discharged so as to be extruded according to the supply speed of the raw material F supplied from the supply port 110, the discharge amount of the molten liquid appropriately changes the supply speed of the raw material. It can be adjusted as appropriate. That is, if the supply speed of the raw material F supplied from the supply port 110 becomes slow, the discharge amount of the molten liquid from the nozzle 130 decreases, and instead, the supply speed of the raw material F supplied from the supply port 110 increases. The faster the speed, the larger the discharge amount of the molten liquid from the nozzle 130.

A known collecting means (not shown) such as a net conveyor or a collecting screen is provided at a position facing the nozzle 130, and the discharged molten liquid is collected in a fibrous solidified state. It can be deposited on the means and collected.

Further, one or more gas flow injection units 140 shown in FIG. 7A are arranged on the outside with reference to the position of the nozzle 130 when the spinning unit 200 is viewed from the front. The gas flow injection unit 140 is configured to be able to inject a heated gas flow from the rear end side to the front end side of the nozzle 130. The gas flow injection unit 140 is connected to a gas flow generation unit 150 that supplies a heated gas flow to the gas flow injection unit 140, so that the gas flow can be supplied to the gas flow injection units 140 and 140, respectively. ing. From the viewpoint of convenience, for example, an air flow can be used as the gas flow.

On the other hand, the spinning unit 200 shown in FIG. 7B is preferably used in the molten electric field spinning method among the melt spinning methods. The spinning unit 200 shown in FIG. 7B includes a nozzle 130 and a gas flow injection unit 140, similarly to the spinning unit 200 shown in FIG. 7A. Regarding the present embodiment, the parts different from the above-described embodiment will be mainly described, and the above-mentioned description of the embodiment will be appropriately applied to the parts not particularly described.

The spinning unit 200 shown in FIG. 7B includes an electrode 160 for charging the nozzle 130, generating an electric field with the nozzle 130, and charging the raw material F. The electrode 160 in this embodiment is made of a conductive material such as metal, and is electrically connected to a high voltage generator 162 that applies a voltage to the electrode 160. The nozzle 130 is also made of a conductive material such as metal.

The shape and arrangement of the electrode 160 can be appropriately changed as long as an electric field can be formed between the electrode 160 and the nozzle 130. In the embodiment shown in the figure, the electrode 160 has a substantially bowl shape arranged so as to surround the nozzle 130, and the nozzle 130 and the electrode 160 are separated from each other. The surface of the electrode 160 facing the nozzle 130 is formed in a concave curved surface. For convenience of explanation, in the following description, the surface of the electrode 160 facing the nozzle 130 is also referred to as a "concave curved surface 161". The electrode 160 has an opening end on the tip end side of the nozzle 130, and the planar shape of the opening end is a circular shape such as a perfect circle or an ellipse. The electrode 160 further includes a high voltage generator 162, and the electrode 160 and the high voltage generator 162 are connected to each other, and a positive or negative voltage is applied by the device.

Further, as shown in FIG. 7B, it is also preferable that the spinning unit 200 includes an electrically insulating wall portion 165 arranged at least on a concave curved surface 161 which is a surface of the electrode 160 facing the nozzle 130. As a result, electric discharge between the nozzle 130 and the electrode 160 can be prevented, and the spinning of the fiber can be stably performed. The wall portion 165 is preferably composed of an insulator such as a ceramic material or a resin-based material. The constituent material of the gas flow injection unit 140 is not particularly limited, but it is preferably selected in consideration of the chargeability of the nozzle 130, and for example, the same material as the wall portion 165 can be used.

The spinning unit 200 shown in FIGS. 6 and 7B may use a collecting means in which a collecting electrode made of a conductive material such as metal is arranged at a position facing the nozzle 130. The collection electrode is preferably grounded or connected to a high voltage generator to which a voltage is applied. In this case, it is also preferable that a voltage different from the voltage applied to the nozzle 130 is applied to the collecting electrode. Further, the collecting means may have a carrying means such as a belt conveyor arranged between the nozzle 130 and the collecting electrode. The fibers collected after spinning can be transported to a downstream process by a transport means.

Hereinafter, a method for producing fibers by the melt spinning method using the melt spinning apparatus 100 will be described. In the production of fibers, a resin composition for melt spinning (filament F) comprising filaments having a melt viscosity of 250 Pa · s or less and a tensile strength of 10 MPa or more at 200 ° C. and a shear rate of 0.1 s- ^{1 as a raw material.} Can be preferably used.

When the melt blow method is adopted as the melt spinning method, first, the filament F is supplied from the supply port 110, and the filament F is heated in the heating unit 120 to obtain a molten liquid. The molten liquid moves so as to be pushed out toward the nozzle 130 according to the speed at which the filament F is supplied from the supply port 110.

Next, the gas flow heated from the gas flow generation unit 150 is supplied to the gas flow injection unit 140, and the molten filament F, that is, the molten liquid of the filament F is injected in a state where the gas flow is injected from the gas flow injection unit 140. Is discharged from the nozzle 130 and spun. As a result, the molten liquid can be drawn while being conveyed to the heated gas stream, and ultrafine fibers can be spun.

When the molten electric field spinning method is adopted as the melt spinning method, first, the filament F is supplied from the supply port 110 and the filament F is heated in the heating unit 120 to obtain a molten liquid, as in the melt blow method. .. The molten liquid moves so as to be pushed out toward the nozzle 130 according to the speed at which the filament F is supplied from the supply port 110.

Next, the gas flow heated from the gas flow generation unit 150 is supplied to the gas flow injection unit 140, and the gas flow is injected from the gas flow injection unit 140, and the molten liquid of the filament F is charged to the nozzle 130. Is discharged into an electric field and spun. At this time, the molten liquid of the filament F is in a state of being charged with a positive polarity or a negative polarity depending on the polarity of the electric field. Taking the spinning unit 200 shown in FIGS. 6 and 7 (b) as an example, this electric field is generated by grounding the nozzle 130 and applying a voltage generated from the high voltage generator 162 to the electrode 160. It can be generated between the nozzle 130 and the electrode 160. A voltage is applied to the electrode 160 so that the absolute value of the potential difference between the nozzle 130 and the electrode 160 is preferably 5 kV or more, preferably 10 kV or more, preferably 100 kV or less, and more preferably 80 kV or less. The discharged molten liquid becomes finer while being three-dimensionally stretched by the electric repulsive force generated inside the molten liquid and the injection of the gas flow, and at the same time, the cooling and solidification of the resin progresses. Small diameter fibers are formed.

Further, regardless of whether the melt blow method or the molten electric field spinning method is adopted in the production of the fiber, the temperature of the gas flow injected from the gas flow injection unit 140 depends on the constituent components of the resin composition. It is preferably 100 ° C. or higher, more preferably 200 ° C. or higher, and preferably 500 ° C. or lower, further preferably 450 ° C. or lower. That is, the gas flow injected from the gas flow injection unit 140 is preferably a heated gas. For the same purpose, the flow rate of the gas flow at the discharge port of the gas flow injection unit 140 is preferably 50 L / min or more, more preferably 100 L / min or more, and preferably 500 L / min or less, further preferably 500 L / min or less. Is 400 L / min or less.

By contacting a gas stream having at least one of such a temperature and an air volume, the stretching efficiency of the molten liquid can be increased due to the external force of the contacted gas stream. Further, since the space temperature around the nozzle can be maintained in a high state, the cooling and solidification of the molten resin can be delayed, and the stretched state of the molten liquid can be maintained for a long time. As a result, ultrafine fibers having a reduced diameter can be efficiently produced. In particular, in the production of fibers by the molten electrospinning method, by bringing a gas flow into contact with the discharged molten liquid and spinning the fibers, in addition to improving the drawing efficiency of the molten liquid by contact with the heated gas, the charged melting is performed. Since the drawing efficiency can be further increased by the electric repulsive force generated in the liquid, there is an advantage that ultrafine fibers having a smaller diameter can be efficiently produced with high productivity.

The fiber produced by the above melt spinning method is an ultrafine fiber called a nanofiber having a fiber diameter of 10 μm or less when the fiber diameter is represented by a circle-equivalent diameter. The nanofiber has a fiber diameter of preferably 0.1 μm or more, preferably 5 μm or less, and more preferably 3 μm or less. In particular, by using a resin composition for melt spinning made of filaments as a raw material in forming fibers, it is possible to obtain high handleability and high continuous supply while preventing thermal deterioration.

For the fiber diameter of the fibers, for example, 200 fibers were arbitrarily selected from a two-dimensional image observed by a scanning electron microscope (SEM), excluding defects such as spun fiber lumps, intersections between fibers, and polymer droplets. It can be measured by directly reading the length when a line orthogonal to the longitudinal direction of the fiber is drawn as the fiber diameter. The median fiber diameter is obtained from the measured fiber diameter distribution, and this is used as the fiber diameter of the present invention.

The nanofibers or their deposits produced by the electrospinning method using the melt spinning apparatus 100 can be used for various purposes as a fiber molded body in which they are integrated. Examples of the shape of the molded body include a sheet, a cotton-like body, and a thread-like body. The fiber molded body may be used by laminating it with another sheet or by containing various liquids, fine particles, fibers and the like. The fiber sheet adheres to human skin, teeth, gums, hair, skin of non-human mammals, teeth, gums, plant surfaces such as branches and leaves for non-medical purposes such as medical purposes, cosmetic purposes, and decorative purposes. It is preferably used as a sheet to be used. It is also suitably used as a high-performance filter having high dust collection and low pressure loss, a battery separator that can be used at a high current density, a cell culture substrate having a high pore structure, and the like. The cotton-like body of the fiber is preferably used as a soundproofing material, a heat insulating material, or the like.

Although the present invention has been described above based on the preferred embodiment, the present invention is not limited to the above embodiment. For example, although the electrode 160 in the above-described embodiment has been described as a mode in which the electrode 160 is connected to the electrode 160 and includes a high voltage generator 162 for applying a voltage to the electrode 160, an electric field for charging the raw material F can be formed. As far as the limit is concerned, there is no particular limitation on the mode. Specifically, the nozzle 130, the electrode 160, and the high voltage generator 162 connected to the nozzle 130 and applying a voltage to the nozzle 130 may be provided, and the nozzle 130 and the collecting electrode may be provided. A voltage may be applied to at least one of the nozzle 130 and the collection electrode to generate an electric field. Even in this case, an electric field for charging the raw material F can be formed.

Regarding the above-described embodiment of the present invention, the following equipment for producing a resin composition for melt spinning, a method for producing the same, and a melt spinning apparatus are disclosed.

<1>
An extrusion-molded part that extrudes a resin composition having a melt viscosity of 250 Pa · s or less at 200 ° C. and a shear rate of 0.1 s- ^{1 into filaments, and a transport that receives the extruded molded product and conveys it to the next process.} With a part,
An apparatus for producing a resin composition for melt spinning, which comprises a filament, wherein the distance between the discharge port of the resin composition and the transport portion is 50 mm or less, and the diameter of the discharge port is 1 mm or more and 50 mm or less.

<2>
The manufacturing apparatus according to <1>, wherein the distance between the discharge port and the transport portion is more preferably 30 mm or less, further preferably 15 mm or less, and preferably 3 mm or more.
<3>
The diameter of the discharge port is preferably 1 mm or more, more preferably 3 mm or more, still more preferably 5 mm or more, preferably 50 mm or less, more preferably 40 mm or less, still more preferably 30 mm or less. The manufacturing apparatus according to <2>.
<4>
The manufacturing apparatus according to any one of <1> to <3>, wherein the transport unit is composed of one or more of a conveyor, a roll, and a liquid tank.
<5>
The manufacturing apparatus according to any one of <1> to <4>, wherein the transport unit is cooled.

<6>
A cooling unit for cooling the molded product transported from the transport unit is further provided.
The manufacturing apparatus according to any one of <1> to <4>, wherein the cooling unit is composed of one or more of a cooling conveyor, a cooling roll, a gas tank, and a liquid tank.
<7>
A transport roll is provided as the transport unit, and a liquid tank containing a liquid is provided as the cooling unit.
The transport roll is arranged in a state of being partially immersed in the liquid.
The molded product discharged from the discharge port is configured to be directly received on the peripheral surface of the transport roll that has not been immersed in the liquid, and the molded product adhered to the peripheral surface by the rotation of the transport roll. The manufacturing apparatus according to <5> or <6>, which is configured to be in contact with the liquid and cooled.
<8>
In any one of <5> to <7>, the ratio of the temperature of the melt to the temperature in the transport unit or the cooling unit is 1.2 times or more and 2.1 times or less in terms of absolute temperature. The manufacturing equipment described.
<9>
The ratio of the temperature of the melt to the temperature in the transport unit or the cooling unit is more preferably 1.3 times or more, still more preferably 1.4 times or more, and more preferably 1.9 in terms of absolute temperature. The manufacturing apparatus according to any one of <5> to <8>, which is not more than twice as much, more preferably 1.7 times or less.

<10>
A method for producing a resin composition for melt spinning, which comprises a filament using the production apparatus according to any one of <1> to <9>.
A melt of a resin composition having a melt viscosity of 250 Pa · s or less at 200 ° C. and a shear rate of 0.1 s- ¹ is extruded from the discharge port having a diameter of 1 mm or more and 50 mm or less to form a filament, and the molded product is formed. A method for producing a resin composition for melt spinning, which comprises a step of cooling while transporting.
<11>
The resin composition has a melt viscosity of more preferably 150 Pa · s or less, further preferably 50 Pa · s or less, preferably 0.05 Pa · s or more, and more preferably at a temperature of 200 ° C. and a shear rate of 0.1 s- ^1. The production method according to <10>, wherein the production method is preferably 0.1 Pa · s or more, more preferably 0.5 Pa · s or more.
<12>
The distance between the discharge port and the transport portion is preferably 50 mm or less, more preferably 30 mm or less, further preferably 15 mm or less, and preferably 3 mm or more, according to the above <10> or <11>. Production method.
<13>
4. The diameter of the discharge port is more preferably 3 mm or more, further preferably 5 mm or more, more preferably 40 mm or less, still more preferably 30 mm or less, according to any one of <10> to <12>. Production method.

<14>
The production method according to any one of <10> to <13>, wherein the ratio of the transfer speed of the molded product to the extrusion speed of the melt is 1 or more and 50 or less.
<15>
The ratio of the transport speed of the molded product to the extrusion speed of the melt is more preferably 3 or more, still more preferably 5 or more, more preferably 35 or less, still more preferably 25 or less. 14> The manufacturing method according to any one of.
<16>
The extrusion speed of the melt is preferably 0.1 m / min or more, more preferably 0.15 m / min or more, still more preferably 0.2 m / min or more, preferably 20 m / min or less, and more preferably 10 m. The production method according to any one of <10> to <15>, wherein it is / min or less, more preferably 5 m / min or less.
<17>
The transport speed of the molded product is preferably 0.2 m / min or more, more preferably 1.0 m / min or more, further preferably 1.5 m / min or more, preferably 200 m / min or less, and more preferably 100 m. The production method according to any one of <10> to <16>, wherein it is / min or less, more preferably 50 m / min or less.

<18>
It is provided with a transport unit that extrudes the molten liquid from a discharge port to convey the molded product, and a cooling unit that cools the molded product.
The cooling unit is a liquid tank in which a liquid is stored.
Using the manufacturing apparatus, the transport unit is a transport roll arranged in a state of being partially immersed in the liquid.
The molded product discharged from the discharge port is directly received on the peripheral surface of the transport roll that has not been immersed in the liquid, and the molded product adhering to the peripheral surface is turned into the liquid by the rotation of the transport roll. The production method according to any one of <10> to <17>, which is brought into contact with each other and cooled.
<19>
The production method according to any one of <10> to <18>, wherein the molded product is cooled using a gas or liquid having a temperature of −40 ° C. or higher and 90 ° C. or lower.
<20>
The cooling temperature in the transport section or the cooling section is preferably −40 ° C. or higher, more preferably 0 ° C. or higher, still more preferably 5 ° C. or higher, preferably 90 ° C. or lower, more preferably 80 ° C. or lower, still more preferably. The production method according to any one of <10> to <19>, wherein the temperature is 70 ° C. or lower.
<21>
The ratio of the temperature of the melt to the temperature in the transport unit or the cooling unit is preferably 1.2 times or more, more preferably 1.3 times or more, still more preferably 1.4 times or more in terms of absolute temperature. The production method according to any one of <10> to <20>, wherein the production method is preferably 2.1 times or less, more preferably 1.9 times or less, and further preferably 1.7 times or less.

<22>
The resin composition contains a thermoplastic resin and contains
The thermoplastic resin is one or more polyolefin resins among polyethylene, polypropylene, ethylene-α-olefin copolymer and ethylene-propylene copolymer.
Polyethylene terephthalate, polybutylene terephthalate, liquid crystal polymer, and one or more of polylactic acid-based resins of polylactic acid and lactic acid-hydroxycarboxylic acid copolymers, or two or more polyester resins.
Polyamide resin,
One or more vinyl-based polymers of polyvinyl chloride, polyvinylidene chloride and polystyrene,
One or more acrylic polymers of polyacrylic acid, polyacrylic acid ester, polymethacrylic acid and polymethacrylic acid ester, and
The above-mentioned <10> to <21>, which is one or more of nylon 6 and one or more nylon polymers, polyvinyl acetate, and polyvinyl acetate-ethylene copolymer. Manufacturing method.
<23>
The production method according to any one of <10> to <22>, wherein the resin composition containing one or more of a polyolefin resin and a polyester resin is used.
<24>
The content of the thermoplastic resin is preferably 70 parts by mass or more, more preferably 75 parts by mass or more, still more preferably 80 parts by mass or more, and preferably 100 parts by mass with respect to 100 parts by mass of the resin composition. Hereinafter, the production method according to <21> or <22>, wherein the production method is more preferably 98 parts by mass or less, still more preferably 95 parts by mass or less.

<25>
The production method according to any one of <10> to <24>, wherein the resin composition containing at least one of an elastomer, a plasticizer, a modifier, a decomposition inhibitor and a charge modifier is used.
<26>
The production method according to <25>, wherein the elastomer contains one or more of an olefin-based elastomer, a styrene-based elastomer, an ester-based elastomer, and a urethane-based elastomer.
<27>
The plasticizer is one or more of polyethylene glycol (PEG), glycerin, glycerin fatty acid ester, glycerin acetate, phosphoric acid ester, hydroxypropyl cellulose and one or more cellulose derivatives of methyl cellulose, lactone, carbamate ester, and phthalic acid. The production method according to <25> or <26>, which comprises two or more kinds.
<28>
The production method according to any one of <25> to <27>, wherein the modifier contains a low stereoregular polyolefin.
<29>
The charge modifier includes a salt of one or more higher fatty acids of Zn stearate, Mg stearate, Li stearate, Zn laurate and Zn ricinoleic acid and a metal, and
Sulfates of alkyl sulfates, alkyl ether sulfates, alkyl sulfonates, alkylbenzene sulfonates, alkylnaphthalene sulfonates, olefin sulfonates, N-alkyl-N-acylaminoalkyl sulfonates, and alkane sulfonates The production method according to any one of <25> to <28>, which comprises one or more of ester salts and sulfonates.
<30>
The content of the additive is preferably 1 part by mass or more, more preferably 3 parts by mass or more, and further preferably 5 parts by mass or more with respect to 100 parts by mass of the resin composition.
The content of the additive is preferably 40 parts by mass or less, more preferably 30 parts by mass or less, still more preferably 20 parts by mass or less, any of the above <25> to <29>. The manufacturing method described in Kaichi.

<31>
The manufacturing apparatus according to any one of <1> to <9>, a supply port to which the resin composition for melt spinning manufactured by the manufacturing apparatus is supplied, and the resin supplied from the supply port. A melt spinning apparatus including a heating unit that melts the composition without applying kneading force, and a nozzle that directly communicates with the heating unit and discharges the melted resin composition.
<32>
A drive unit having an electric motor is further provided in the vicinity of the supply port.
The melt spinning apparatus according to <31>, wherein the resin composition can be continuously supplied to the supply port side at a predetermined speed by rotation of the electric motor.
<33>
The drive unit includes a shaft for transmitting the rotation of the electric motor, a gear connected to the shaft, and a bearing that can be rotated by the rotation of the gear.
The axial direction of the gear and the axial direction of the bearing are arranged in the same state.
The melt spinning apparatus according to <32>, wherein the resin composition can be supplied to the supply port side by disposing the resin composition between the gear and the bearing.

<34>
The melt spinning apparatus according to any one of <31> to <33>, further comprising a gas flow injection unit for transporting the resin composition discharged from the nozzle to a gas flow.
<35>
The melt spinning apparatus according to any one of <31> to <34>, further comprising an electrode for charging the resin composition discharged from the nozzle.
<36>
The melt spinning apparatus according to <35>, wherein the electrodes are arranged so as to be separated from the nozzle and surround the nozzle.
<37>
The melt spinning device according to <35> or <36>, wherein the electrode is connected to a high voltage generator for applying a positive or negative voltage to the electrode.
<38>
The electrode has a substantially bowl shape, which is arranged so as to surround the nozzle and whose surface facing the nozzle is formed in a concave curved surface shape.
The melt spinning apparatus according to any one of <35> to <37>, wherein the electrically insulating wall portion is arranged at least on the concave curved surface.

<39>
The decomposition inhibitor contains one or more carbodiimide compounds among the monocarbodiimide compound and the polycarbodiimide compound.
The monocarbodiimide compounds include diphenylcarbodiimide, di-2,6-dimethylphenylcarbodiimide, di-2,6-diethylphenylcarbodiimide, di-2,6-diisopropylphenylcarbodiimide, di-2,6-di-tert-butyl. Phenylcarbodiimide, di-o-tolylcarbodiimide, di-p-tolylcarbodiimide, di-2,4,6-trimethylphenylcarbodiimide, di-2,4,6-triisopropylphenylcarbodiimide, and di-2,4,6 -Aromatic monocarbodiimide compounds of triisobutylphenylcarbodiimide; alicyclic monocarbodiimide compounds of di-cyclohexylcarbodiimide and di-cyclohexylmethanecarbodiimide; di-isopropylcarbodiimide, and one of the aliphatic monocarbodiimide compounds of di-octadecylcarbodiimide Or two or more types,
The polycarbodiimide compound has aromas of poly (4,4'-diphenylmethanecarbodiimide), poly (p-phenylene carbodiimide), poly (m-phenylene carbodiimide), poly (diisopropylphenylcarbodiimide), and poly (triisopropylphenylcarbodiimide). Group Polycarbodiimide; The production method according to any one of <25> to <30>, which is one or more of poly (dicyclohexylmethanecarbodiimide) alicyclic polycarbodiimides.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the scope of the present invention is not limited to such examples.

[Examples 1-1 to 1-13 and Comparative Examples 1-1 to 1-2]
In this example and the comparative example, the influence of the distance D1 between the discharge port 24 and the transport portion 30 on the filament production when the resin composition composed of the filament is produced is investigated. Using a manufacturing apparatus 10 having a structure as shown in FIG. 2 and not provided with a cooling gas supply unit 45, polypropylene (PP; manufactured by PolyMirae, MF650Y, melting point 160 ° C.) and a modifier are used as thermoplastic resins. Low crystalline polyolefin (L-MODU S400, manufactured by Idemitsu Kosan Co., Ltd.) was used as a raw material, and after melt-kneading, a resin melt was extruded from a discharge port 24 to obtain a molded product S. The diameter of the discharge port was 5 mm, and the distance D1, the extrusion speed V1 of the molten liquid from the discharge port 24, the transfer speed V2 of the molded product S, and the V2 / V1 ratio were as shown in Table 1 below. Further, the transport unit 30 is in the form of a belt conveyor, and a resin composition composed of filaments of each Example and Comparative Example is produced by naturally air-cooling the molded product S while transporting it or water-cooling it by immersing it in water. did.

[Whether or not filament can be produced]
For each Example and Comparative Example, whether or not the filament could be produced was evaluated according to the following evaluation criteria. The results are shown in Table 1.
◯: A filament having a filament cross-sectional diameter of 1 mm or more measured by the above-mentioned filament cross-sectional diameter measuring method can be produced.
X: The cross-sectional diameter of the filament measured by the above-mentioned method for measuring the cross-sectional diameter of the filament is less than 1 mm and the filament cannot be stably produced, or the produced filament is easily bent and has an unstable shape. It is difficult to collect and use as a product.

[Cross-sectional diameter of filament and its standard deviation]
The cross-sectional diameter of the filament was measured by the above-mentioned method for measuring the cross-sectional diameter of the filament, and the standard deviation was obtained together with this. The smaller the standard deviation, the more uniform the cross-sectional diameter of a single filament. The results are shown in Table 1.
In this evaluation, the column indicated by "-" in Table 1 is due to the fact that a filament having a length that can be used for measuring the cross-sectional diameter cannot be manufactured, or that the manufactured filament has an unstable shape. Therefore, it is difficult to recover the filament, and the cross-sectional diameter could not be measured.

[Measurement of roundness of filament cross section]
The roundness of the cross section of the filament was measured by measuring the major axis and the minor axis at each measurement point in the same manner as in the measurement of the cross-sectional diameter described above, and calculating the minor axis / major axis ratio at each measurement point. The arithmetic mean value of the minor axis / major axis ratio at all measurement points was defined as roundness. The roundness in this measurement method is expressed in the range of more than 0 (zero) and 1 or less, and is calculated as 1 if the cross-sectional shape of the filament is a perfect circle. The closer the roundness is to 1, the more the cross-sectional shape is a perfect circle. It is close to. The results are shown in Table 1. In this evaluation, the column indicated by "-" in Table 1 indicates that the cross-sectional shape is a non-circular shape such as a crescent shape or an arch shape, and the roundness was not measured. Since the shape of the discharge port 24 in the filament manufacturing apparatus 10 used in this embodiment is a circular shape having a roundness close to 1, the fact that the roundness of the filament cross section is close to 1 means that the resin melt liquid is used. This means that there is little change in shape between the cross-sectional shape immediately after extrusion molding from the discharge port 24 and the cross-sectional shape of the filament after cooling and solidification, and the filament can be stably produced. The results are shown in Table 1.

As shown in Table 1, it can be seen that by setting the distance D1 between the discharge port 24 and the transport portion 30 in the range of 1 mm or more and 50 mm or less, filaments having a predetermined diameter can be stably and continuously manufactured. Further, by setting at least one of the extrusion speed V1 of the molten liquid from the discharge port 24, the transport speed V2 of the molded product S and the V2 / V1 ratio in a suitable range, the variation in the cross-sectional diameter of the filament is small and the cross section Filaments having a shape close to a perfect circle and having a good cross-sectional shape can be continuously and stably produced.

[Examples 2-1 to 2-2]
This example relates to the formability of fibers produced from filaments.

[Fiber manufacturing]
The resin composition composed of the filaments obtained in Example 1-12 was supplied to the melt spinning apparatus 100 shown in FIG. 6 to produce the fibers shown in Example 2-1. Further, the resin composition composed of the filaments obtained in Example 1-13 was supplied to the melt spinning apparatus 100 shown in FIG. 6 to produce the fibers shown in Example 2-2. Each example used the spinning unit 200 shown in FIG. 6 and was manufactured by the molten electric field spinning method. The manufacturing conditions are shown below.

[Fiber manufacturing conditions]
-Manufacturing environment: 27 ° C, 50% RH
-Heating temperature in the heating unit 120: 250 ° C
-Discharge rate of molten liquid from nozzle 130: 2 to 6 g / min
-Voltage applied to nozzle 130 (stainless steel): 0 kV (grounded to ground)
-Voltage applied to electrode 160 (stainless steel): -20 kV
-Inner diameter at the tip of the nozzle 130: 0.4 mm
-Distance between the tip of the nozzle 130 and the collecting means: 600 mm
-Temperature of the air flow injected from the gas flow injection unit 140: 450 ° C.
-Flow rate of air flow injected from gas flow injection unit 140: 150 L / min

[Measurement of median fiber diameter]
Under the production conditions of Examples and Comparative Examples, the fiber diameter of the spun fiber was measured by the method described above. The results are shown in Table 2.

As shown in Table 2, it can be seen that the fibers produced using the filaments obtained in the examples are all extremely fine and the fiber production efficiency is high.

10 Filament manufacturing equipment 20 Extrusion molding unit 30 Transport unit 40 Cooling unit 100 Melting spinning equipment 110 Supply port 120 Heating unit 130 Nozzle

Claims (13)

An extrusion-molded part that extrudes a resin composition having a melt viscosity of 250 Pa · s or less at 200 ° C. and a shear rate of 0.1 s- ^{1 into filaments, and a transport that receives the extruded molded product and conveys it to the next process.} With a part,
An apparatus for producing a resin composition for melt spinning, which comprises a filament, wherein the distance between the discharge port of the resin composition and the transport portion is 50 mm or less, and the diameter of the discharge port is 1 mm or more and 50 mm or less. The manufacturing apparatus according to claim 1, wherein the transport unit is composed of one or more of a conveyor, a roll, and a liquid tank. The manufacturing apparatus according to claim 1 or 2, wherein the transport unit is cooled. A cooling unit for cooling the molded product transported from the transport unit is further provided.
The manufacturing apparatus according to claim 1 or 2, wherein the cooling unit is composed of one or more of a cooling conveyor, a cooling roll, a gas tank, and a liquid tank. The manufacturing apparatus according to claim 3 or 4, wherein the ratio of the temperature of the melt to the temperature in the transport unit or the cooling unit is 1.2 times or more and 2.1 times or less in terms of absolute temperature. A method for producing a resin composition for melt spinning, which comprises a filament using the production apparatus according to any one of claims 1 to 5.
A melt of a resin composition having a melt viscosity of 250 Pa · s or less at 200 ° C. and a shear rate of 0.1 s- ¹ is extruded from the discharge port having a diameter of 1 mm or more and 50 mm or less to form a filament, and the molded product is formed. A method for producing a resin composition for melt spinning, which comprises a step of cooling while transporting. The manufacturing method according to claim 6, wherein the ratio of the transport speed of the molded product to the extrusion speed of the melt is 1 or more and 50 or less. The production method according to claim 6 or 7, wherein the molded product is cooled using a gas or liquid having a temperature of −40 ° C. or higher and 90 ° C. or lower. The production method according to any one of claims 6 to 8, wherein the resin composition containing one or more of a polyolefin resin and a polyester resin is used. The production method according to any one of claims 6 to 9, wherein the resin composition containing at least one of an elastomer, a plasticizer, a modifier, a decomposition inhibitor and a charge modifier is used. The manufacturing apparatus according to any one of claims 1 to 5, a supply port to which the resin composition for melt spinning manufactured by the manufacturing apparatus is supplied, and the resin composition supplied from the supply port. A melt spinning apparatus including a heating unit that melts the resin composition without applying a kneading force, and a nozzle that directly communicates with the heating unit and discharges the melted resin composition. The melt spinning apparatus according to claim 11, further comprising a gas flow injection unit for transporting the resin composition discharged from the nozzle to a gas flow. The melt spinning apparatus according to claim 11, further comprising an electrode for charging the resin composition discharged from the nozzle.

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