JP7543663B2 - Eccentric core-sheath crimped nonwoven fabric manufacturing equipment - Google Patents

Description

The present invention relates to an apparatus for manufacturing eccentric core-sheath crimped nonwoven fabrics equipped with a means for imparting crimping properties.

In the spunbond process, which is one of the nonwoven fabric manufacturing methods, a thermoplastic resin is melt-spun from multiple spinning holes in a spinneret by a spinning means to form a filament aggregate, which is a bundle of filaments. This filament aggregate is cooled to the desired hardness by a cooling means that supplies a controlled uniform flow of cooling air from the horizontal direction, and at the same time, is pulled vertically by a stretching means. This allows the fiber strength and fiber diameter of the filament aggregate to be adjusted.

For example, Patent Document 1 describes a filament having an island-in-sea structure produced by a spunbonding method, in which an air jet stuffer device is used after the filament is produced to impart crimping properties to the highly uniform island-in-sea structure filament. In this way, in order to impart crimping properties to a filament having an island-in-sea structure, post-processing after the filament is produced is essential, which may result in an increase in the size of the production equipment and an increase in costs.

JP 2010-150721 A

The object of the present invention is to provide an apparatus for producing eccentric core-sheath crimped nonwoven fabric that can efficiently impart crimping properties to filaments during filament production, thereby preventing the production apparatus from becoming larger and the costs from increasing.

In order to solve the above problems, the manufacturing apparatus for eccentric core-sheath nonwoven fabric comprises a spinning means for extruding molten thermoplastic resin from a spinneret as a filament assembly composed of filaments, a stretching means for aerodynamically stretching the filament assembly, and a cooling means disposed between the spinning means and the stretching means for supplying cooling air to the filament assembly to cool it, the filaments being eccentric core-sheath composite fibers comprising a first component which is a core component and a second component which is a sheath component, and the cooling means for cooling the filament assembly. The device has a pair of blowing ports sandwiching the combined filament, each of which is divided into at least three stages in the vertical direction, and each stage of the blowing ports is provided with a wind direction adjustment means for adjusting the wind direction of the cooling air so that each stage has a different wind direction, and the wind direction adjustment means adjusts the intersection of the wind direction of the cooling air at the upper end of the blowing port and the perpendicular bisector of the spinneret between the straight line connecting the upper ends of the pair of blowing ports and the lower surface of the spinneret to impart crimping to the filaments.

The manufacturing device for the eccentric core-sheath nonwoven fabric may also be characterized in that the angle α of the cooling air at the upper end of the outlet with respect to the perpendicular bisector of the spinneret is 60 to 90 (°).

The manufacturing device for the eccentric core-sheath nonwoven fabric may also be characterized in that the angle β that the cooling air makes at the lower end of the blowing port with respect to the perpendicular bisector of the spinneret is 60 to 90 (°).

The manufacturing device for the eccentric core-sheath nonwoven fabric may be characterized in that the cooling air from the upper stage of the air outlet has a higher wind speed and a lower temperature than the cooling air from the lower stage of the air outlet.

The manufacturing device for the eccentric core-sheath nonwoven fabric may be characterized in that the cooling air from the upper stage of the air outlet has a higher wind speed and a lower temperature than the cooling air from the lower stage of the air outlet.

The manufacturing device for the eccentric core-sheath nonwoven fabric may also be characterized in that the air direction adjustment means provided at each stage of the air outlet discretely or continuously changes the air direction of the cooling air from a direction inclined upward from the horizontal to a direction inclined downward from the horizontal as the cooling air moves from the upper stage of the air outlet to the lower stage of the air outlet so as to prevent interference between the cooling air streams.

The manufacturing apparatus for the eccentric core-sheath nonwoven fabric may be characterized in that the first component and the second component each contain a thermoplastic resin as a main component, the first component includes a long-chain branched polyolefin resin, and the long-chain branched polyolefin resin has a melt flow rate of 4 g/10 min or more measured at a load of 2.16 kg and a temperature of 230° C. in accordance with ASTM D1238.

The manufacturing apparatus for the eccentric core-sheath nonwoven fabric may be characterized in that the first component contains the long-chain branched polyolefin resin in an amount of 0.5% by mass or more and 10% by mass or less based on the total solid content of the first component.

The manufacturing apparatus for the eccentric sheath-core nonwoven fabric may be characterized in that the eccentric sheath-core composite fiber contains the first component in an amount of 10% by mass or more and 40% by mass or less based on the total solid content of the eccentric sheath-core composite fiber.

The manufacturing apparatus for the eccentric core-sheath nonwoven fabric may also be characterized in that the first component and the second component each contain a thermoplastic resin in an amount of 90% by mass or more and 100% by mass or less based on the total solid content of each component.

The manufacturing device for the eccentric core-sheath nonwoven fabric may also be characterized in that the first component and the second component each have polypropylene as a main component.

The manufacturing apparatus for the eccentric core-sheath nonwoven fabric may be characterized in that the first component is mainly made of polypropylene, and the long-chain branched polyolefin resin is long-chain branched polypropylene.

The eccentric core-sheath nonwoven fabric manufacturing apparatus further comprises a step of: (a) dispersing a polymer having a mesopentad fraction [mmmm] of 30 mol% or more and 80 mol% or less; (b) dispersing a racemic pentad fraction [rrrr] and a racemic triad fraction [1-mmmm] that satisfy the relationship: [rrrr]/[1-mmmm]≦0.1; (c) dispersing a racemic meso racemic meso pentad fraction [rmrm] of more than 2.5 mol%; and (d) dispersing a meso triad fraction [mm], a racemic triad fraction [rr], and a triad fraction [mr] that satisfy the relationship: [mm]×[rr]/[mr] ² e) the weight average molecular weight [Mw] is 10,000 or more and 200,000 or less, f) the weight average molecular weight [Mw] and the number average molecular weight [Mn] satisfy the relationship of molecular weight distribution [Mw]/[Mn]≦4, and g) the amount of extractables with boiling diethyl ether is 0% by mass or more and 10% by mass or less based on the total solid content of the low crystalline polyolefin resin.

The present invention provides an apparatus for producing eccentric core-sheath crimped nonwoven fabric that can effectively impart crimping properties to filaments during filament production, thereby preventing the production apparatus from becoming larger and the costs from increasing.

FIG. 2 is a cross-sectional view showing an example of a composite fiber according to one embodiment of the present invention. 1 is a schematic diagram showing an example of a nonwoven fabric manufacturing apparatus according to an embodiment of the present invention. FIG. 3 is a perspective view illustrating the air outlets of the pair of cooling fans shown in FIG. 2 . 4 is a cross-sectional view illustrating a pair of cooling fans taken along the line IV-IV in FIG. 3.

An embodiment of the present invention will be described in detail with reference to Figures 1 to 4. However, the present invention is not limited to this embodiment.

<Composite fiber>
The composite fiber (hereinafter also referred to as "filament") 10 according to the present embodiment includes a first component 1 (see FIG. 2) and a second component 2 (see FIG. 2) which are fiber forming components. The first component and the second component each mainly consist of a thermoplastic resin. The first component includes a long-chain branched polyolefin resin. The long-chain branched polyolefin resin has a melt flow rate (MFR) of 4 g/10 min or more measured at a load of 2.16 kg and a temperature of 230° C. according to ASTM D1238. The composite fiber having such a configuration is a crimped fiber having crimping properties. In this specification, the "crimping properties" of the fiber refers to the property of the fiber being shrunk and twisted. The "crimped fiber" refers to a fiber that has crimping properties and shows a shape that is not straight, such as a spiral or crimped shape. The composite fiber according to the present embodiment will be described in detail below.

(First Component)
The first component is mainly composed of a thermoplastic resin. That is, the first component can contain the thermoplastic resin in an amount of 90% by mass or more and 100% by mass or less based on the total solid content of the first component. Examples of thermoplastic resins that can be used for the first component include polyolefin resins such as polypropylene (PP) and polyethylene (PE). From the viewpoint of spinnability and strength of the composite fiber, polypropylene (PP) is preferably used as the thermoplastic resin.

In this embodiment, the first component contains a long-chain branched polyolefin resin as one type of thermoplastic resin. The first component contains the long-chain branched polyolefin resin in an amount of 0.5% by mass or more, more preferably 1% by mass or more, based on the total solid content of the first component. The first component also contains the long-chain branched polyolefin resin in an amount of 10% by mass or less, more preferably 5% by mass or less, and even more preferably 3% by mass or less, based on the total solid content of the first component. In other words, the first component contains at least two types of thermoplastic resins, namely, a long-chain branched polyolefin resin and a thermoplastic resin that is not a long-chain branched polyolefin resin. Three or more types of thermoplastic resins in the first component can also be used in combination. If the long-chain branched polyolefin in the first component is less than 0.5% by mass, the effect of increasing the degree of crimping of the composite fiber is reduced, and if it is more than 10% by mass, the spinnability is reduced.

In this specification, "long-chain branched polyolefin resin" refers to a polyolefin resin having a structure in which a long side chain branches from a linear polymer. In this specification, "long side chain" refers to a carbon chain that constitutes one side chain having 12 or more carbon atoms. Since the long-chain branched polyolefin resin has a structure in which a long side chain branches, the fluidity of the long-chain branched polyolefin resin in a molten state is low. Therefore, when a thermoplastic resin containing a long-chain branched polyolefin resin is spun as a raw material, when the filament extruded from the spinneret 20 (see FIG. 2) is stretched by high-pressure air F (see FIG. 2), the molecular orientation of the filament is easily promoted and crystallization is promoted. As the crystallization of one of the fiber-forming components of the composite fiber is promoted and hardened, the difference in elasticity with the other component becomes large, and the composite fiber containing the long-chain branched polyolefin resin has a high degree of crimping. In addition, a nonwoven fabric using a composite fiber containing a long-chain branched polyolefin resin is likely to be bulky, has excellent cushioning properties, and is less likely to wrinkle even when subjected to shear deformation.

Here, the higher the blend ratio of the long-chain branched polyolefin resin in the first component, the greater the degree of crimping of the resulting composite fiber. In addition, nonwoven fabrics using this tend to be bulky, have high cushioning properties, and are less prone to wrinkling. On the other hand, the higher the blend ratio of the long-chain branched polyolefin resin in the first component, the lower the spinnability of the composite fiber produced. Therefore, the blend ratio of the long-chain branched polyolefin resin can be set taking into account the spinnability of the composite fiber and the physical properties of the nonwoven fabric using it.

The long-chain branched polyolefin resin applicable to the first component preferably has a melt flow rate (MFR) of 4 g/10 min or more, measured at a load of 2.16 kg and a temperature of 230° C. according to ASTM D1238. As the long-chain branched polyolefin resin applicable to the first component, commercially available products (for example, for the purpose of illustration and not limitation, a long-chain branched polyolefin resin with a melting point of 162° C. and an MFR of 8 g/10 min, and a long-chain branched polyolefin resin with a melting point of 162° C. and an MFR of 4 g/10 min) can be suitably used. If the MFR of the long-chain branched polyolefin resin is lower than 4 g/10 min, the spinnability of the filament made from the thermoplastic resin containing this resin is significantly reduced. When a polypropylene-based resin is used as the long-chain branched polyolefin resin, it is preferable to use a polypropylene-based resin as the thermoplastic resin of the first component from the viewpoint of compatibility, etc.

A low crystalline polyolefin resin may be used in combination as the thermoplastic resin of the first component. For example, the low crystalline polyolefin resin satisfying the following a) to g) may be contained in an amount of 5% by mass to 50% by mass based on the total solid content of the first component.
a) The mesopentad fraction [mmmm] is 30 mol % or more and 80 mol % or less.
b) The racemic pentad fraction [rrrr] and [1-mmmm] satisfy the relationship: [rrrr]/[1-mmmm]≦0.1.
c) The racemic-mesoracemic-meso pentad fraction [rmrm] is greater than 2.5 mol %.
d) The mesotriad fraction [mm], the racemic triad fraction [rr], and the triad fraction [mr] satisfy the relationship: [mm]×[rr]/[mr] ² ≦2.0.
e) The weight average molecular weight [Mw] is 10,000 or more and 200,000 or less.
f) The weight average molecular weight [Mw] and the number average molecular weight [Mn] satisfy the relationship of molecular weight distribution [Mw]/[Mn]≦4.
g) The amount of extractables with boiling diethyl ether is from 0% by mass to 10% by mass based on the total solid content of the low crystalline polyolefin resin.

As a low crystalline polyolefin resin applicable to the first component, commercially available polypropylene (for example, polypropylene with a melting point of 52°C and MFR of 50 g/10 min, for example and not for limiting purposes) can be suitably used.

Low-crystalline polyolefin resins are difficult to crystallize because the side chains protrude in random directions, and fibers and nonwoven fabrics made from them tend to be soft, less stiff, and pleasant to the touch.

(Second Component)
The second component is mainly composed of a thermoplastic resin. Specifically, the second component contains the thermoplastic resin in an amount of 90% by mass or more and 100% by mass or less based on the total solid content of the second component.

Thermoplastic resins that can be used as the main component of the second component include polyolefin resins such as polypropylene (PP) and polyethylene (PE). One type of thermoplastic resin may be used, or two or more types may be used in combination. From the viewpoint of the spinnability and strength of the composite fiber, polypropylene (PP) is preferably used as the thermoplastic resin.

A low crystalline polyolefin resin may be used in combination as the thermoplastic resin of the second component. For example, the low crystalline polyolefin resin satisfying the following a) to g) may be contained in an amount of 5% by mass to 50% by mass based on the total solid content of the second component.
a) The mesopentad fraction [mmmm] is 30 mol % or more and 80 mol % or less.
b) The racemic pentad fraction [rrrr] and [1-mmmm] satisfy the relationship: [rrrr]/[1-mmmm]≦0.1.
c) The racemic-mesoracemic-meso pentad fraction [rmrm] is greater than 2.5 mol %.
d) The mesotriad fraction [mm], the racemic triad fraction [rr], and the triad fraction [mr] satisfy the relationship: [mm]×[rr]/[mr] ² ≦2.0.
e) The weight average molecular weight [Mw] is 10,000 or more and 200,000 or less.
f) The weight average molecular weight [Mw] and the number average molecular weight [Mn] satisfy the relationship of molecular weight distribution [Mw]/[Mn]≦4.
g) The amount of extractables with boiling diethyl ether is from 0% by mass to 10% by mass based on the total solid content of the low crystalline polyolefin resin.

As a low crystalline polyolefin resin applicable to the second component, a commercially available polypropylene with a melting point of 52°C (for illustrative purposes, not for limiting purposes, for example, polypropylene with a melting point of 52°C and MFR of 50g/10min) can be suitably used.

Low-crystalline polyolefin resins are difficult to crystallize because the side chains are not aligned in the same direction, and fibers and nonwoven fabrics made from them tend to be soft, less stiff, and pleasant to the touch.

(Other ingredients)
In addition to the thermoplastic resin, the first component and the second component of the composite fiber may each contain other components as necessary within the scope of the present invention.

Other components include, for example, various stabilizers such as known heat stabilizers and weather stabilizers, antistatic agents, slip agents, antiblocking agents, antifogging agents, lubricants, dyes, pigments, natural oils, synthetic oils, waxes, etc.

Examples of stabilizers include antioxidants such as 2,6-di-t-butyl-4-methylphenol (BHT); phenolic antioxidants such as tetrakis[methylene-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]methane, β-(3,5-di-t-butyl-4-hydroxyphenyl)propionic acid alkyl ester, and 2,2'-oxamidobis[ethyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate; fatty acid metal salts such as zinc stearate, calcium stearate, and calcium 1,2-hydroxystearate; and polyhydric alcohol fatty acid esters such as glycerin monostearate, glycerin distearate, pentaerythritol monostearate, pentaerythritol distearate, and pentaerythritol tristearate. These may also be used in combination.

Examples of lubricants include oleamide, erucamide, and stearamide.

It may also contain fillers such as silica, diatomaceous earth, alumina, titanium oxide, magnesium oxide, pumice powder, pumice balloon, aluminum hydroxide, magnesium hydroxide, basic magnesium carbonate, dolomite, calcium sulfate, potassium titanate, barium sulfate, calcium sulfite, talc, clay, mica, asbestos, calcium silicate, montmorillonite, bentonite, graphite, aluminum powder, and molybdenum sulfide.

<Difference in the structure of the composite fiber between the conventional technology and the present embodiment>
Among the composite fibers in the prior art (e.g., Patent Document 1, etc.), there is one having a sea-island structure in which polylactic acid-based resin and polyolefin-based resin are uniformly and finely dispersed and blended. This composite fiber exhibits good fiber properties (fiber strength, breaking elongation, boiling water shrinkage, etc.) and good abrasion resistance, but because the composite fiber is highly uniform, it is very difficult to impart crimping properties during the composite fiber production process. Therefore, in order to impart crimping properties to this composite fiber, a separate process of imparting crimping properties using an air jet stuffer device or the like must be performed on the produced composite fiber, and therefore there has been a demand for suppressing the increase in size of the production device and the increase in cost.

In the configuration of the composite fiber in this embodiment, as shown in FIG. 1, the fiber-forming components are arranged in two zones in the cross section, i.e., in the cross section perpendicular to the longitudinal direction of the composite fiber. Specifically, the first component 1 is arranged as the core component in one zone, and the second component 2 is arranged as the sheath component surrounding the first component 1 in the other zone, resulting in an eccentric core-sheath type composite fiber in which the core component is positioned offset from the center of the fiber. As a result, by adopting an eccentric core-sheath type composite fiber, it is possible to impart crimping properties during the composite fiber production process, as will be described in detail later, and this makes it possible to suppress the increase in size and cost of the manufacturing equipment.

In the composite fiber according to this embodiment, a first component containing a long-chain branched polyolefin resin and a second component different from the first component are arranged in asymmetric zones in a cross section perpendicular to the longitudinal direction of the composite fiber. The first component is more likely to undergo molecular orientation and crystallization when spun and stretched than the second component. Therefore, the composite fiber according to this embodiment exhibits high crimpability. In addition, nonwoven fabrics using this composite fiber have good stretchability and cushioning properties, and are bulky.

The composite fiber according to this embodiment is formed from two fiber-forming components, a first component and a second component, but is not limited thereto. For example, the composite fiber may be formed from three or more types of fiber-forming components including the first component and the second component, as long as the materials and in-fiber arrangement do not interfere with the crimpability of the composite fiber.

The fineness of the composite fiber according to this embodiment can be appropriately set depending on the application of the nonwoven fabric, but is 0.1 denier or more and less than 10 denier, preferably 0.3 denier or more and less than 5 denier, and more preferably 0.5 denier or more and less than 3 denier.

(Fiber properties: crimping property)
The degree of crimping of the fiber can be indicated, for example, by the number of crimps of the fiber measured in accordance with Japanese Industrial Standard JIS L 1015. The number of crimps of the conjugated fiber of the present embodiment can be appropriately set by adjusting the compounding ratio of the components, but is preferably 18 or more, more preferably 20 to 50, per 25 mm of fiber, and from the viewpoint of visibility and texture of the resulting nonwoven fabric, still more preferably 20 to 40, and most preferably 20 to 30.

<Nonwoven fabric>
The nonwoven fabric according to the present embodiment is made of the composite fiber according to the present embodiment described above. The nonwoven fabric according to the present embodiment contains the composite fiber in an amount of preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, still more preferably 80% by mass or more, and even more preferably 90% by mass or more, based on the total solid content of the nonwoven fabric. The nonwoven fabric according to the present embodiment may have a single-layer structure consisting of one layer, or may have a multilayer structure consisting of multiple layers. When the nonwoven fabric is a laminate having a multilayer structure, it is preferable that the nonwoven fabric contains the composite fiber in an amount of 60% by mass or more, based on the total solid content of the entire nonwoven fabric.

(Layer structure)
As described above, the nonwoven fabric according to the present embodiment may have a single-layer structure made of one layer, or may have a multilayer structure made of multiple layers. Each of the multiple layers of the nonwoven fabric having a multilayer structure according to the present embodiment may be a nonwoven fabric formed separately.

For example, the nonwoven fabric having a multilayer structure according to the present embodiment may have a structure in which a single-layer nonwoven fabric according to the present embodiment is used as one layer, and a spunbond nonwoven fabric made of non-shrinkable fibers, for example, produced by the spunband method, is laminated on the single layer as a surface layer. In this case, the fineness of the non-shrinkable fibers may be, for example, preferably 0.5 denier or more and less than 2.5 denier, and more preferably 0.5 denier or more and less than 1.5 denier. With this structure, a nonwoven fabric in the form of a laminate can be obtained that is not only less prone to wrinkles, but also has excellent surface smoothness and improved water resistance. In addition, the nonwoven fabric according to the present embodiment may be laminated with another nonwoven fabric in order to improve the surface properties or impart functionality to the nonwoven fabric according to the present embodiment having a single layer structure.

Non-limiting examples of the configuration of such a laminated nonwoven fabric include the following. Among the following examples, a spunbonded nonwoven fabric described as "mainly made of crimped composite fibers" is intended to be a single-layer nonwoven fabric according to this embodiment. A spunbonded nonwoven fabric described as "mainly made of non-crimped fibers" can be obtained by controlling the manufacturing conditions of the spunbonding method.
(a) A two-layer nonwoven fabric consisting of a spunbond nonwoven fabric (mainly made of non-crimping fibers) and a spunbond nonwoven fabric (mainly made of crimped composite fibers).
(b) A three-layer nonwoven fabric consisting of spunbond nonwoven fabric (mainly made of non-crimped fibers)/spunbond nonwoven fabric (mainly made of crimped composite fibers)/spunband nonwoven fabric (mainly made of non-crimped fibers).
(c) A three-layer nonwoven fabric consisting of spunbond nonwoven fabric (mainly made of non-crimped fibers)/spunbond nonwoven fabric (mainly made of crimped composite fibers)/meltblown nonwoven fabric.
(d) A four-layer nonwoven fabric consisting of spunbond nonwoven fabric (mainly made of non-crimped fibers)/spunbond nonwoven fabric (mainly made of crimped composite fibers)/meltblown nonwoven fabric/spunbond nonwoven fabric (mainly made of non-crimped fibers).
(e) A five-layer nonwoven fabric consisting of spunbond nonwoven fabric (mainly made of non-crimped fibers)/spunbond nonwoven fabric (mainly made of crimped composite fibers)/meltblown nonwoven fabric/spunband nonwoven fabric (mainly made of crimped composite fibers)/spunband nonwoven fabric (mainly made of non-crimped fibers).

The basis weight of the nonwoven fabric constituting each layer is preferably in the range of 2.0 to 25 g/ ^m2 . If the basis weight is too high, the nonwoven fabric constituting that layer may inhibit the function of the nonwoven fabric constituting the other layers. If the basis weight is too low, the nonwoven fabric constituting that layer may not have a large effect of imparting function to the multi-layered nonwoven fabric according to this embodiment.

<Nonwoven fabric manufacturing equipment>
The filament aggregate 3 and the nonwoven fabric 5 including the filament aggregate 3 according to the present embodiment can be obtained by a nonwoven fabric manufacturing apparatus using a normal composite melt spinning method without using any special device. Among them, a nonwoven fabric manufacturing apparatus using a spunbond method, which has excellent productivity, is preferably used.

Figure 2 shows a schematic diagram of an example of a nonwoven fabric manufacturing apparatus according to one embodiment of the present invention for illustrative purposes, not for limiting purposes. The open arrows A, B, and C in the figure represent the spinning direction of the filament aggregate 3, the conveying direction (MD direction) of the filament aggregate 3, and the rotation direction of the collection belt 51, respectively. The open arrows D, E, and F in the figure represent the cooling air, separation gas, and high-pressure air, respectively. Furthermore, the X-axis direction in the figure represents the conveying direction B, the Z-axis direction represents a direction perpendicular to the X-axis direction and parallel to the spinning direction A, and the Y-axis direction represents the CD direction perpendicular to the X-axis direction and the Z-axis direction, respectively.

The spunbond nonwoven fabric manufacturing apparatus 100 is composed of a first extruder 11 and a second extruder 12 (spinning means), a spinneret 20 (spinning means), a pair of cooling blowers 30L, 30R (cooling means), an ejector 40 (stretching means), a collection conveyor 50, a hot embossing roll 60, and a winder 70. The following is an overview of each of these components.

The first extruder 11 melts the first component 1 and sends a predetermined flow rate of the melt to the spinneret 20 (spinning means) by the rotation of the spiral first rotor 13. Similarly, the second extruder 12 melts the second component 2 and sends a predetermined flow rate of the melt to the spinneret 20 by the rotation of the spiral second rotor 14.

The spinneret 20 has multiple composite spinning nozzles 21 (see Figure 4) configured to form and eject the desired fiber structure, and spins out a bundle of multiple filaments (hereinafter referred to as a "filament aggregate") 3 in the direction of gravity, which is made up of composite fibers 10 (see Figure 1) formed by combining the melts from the first extruder 11 and the second extruder 12.

The pair of cooling blowers 30L, 30R are of the open type, and blow cooling air D in the X-axis direction, which is perpendicular to the spinning direction A, to the spun filament aggregate 3 to cool the filament aggregate 3. In addition, the high-temperature separation gas E discharged from the filament aggregate 3 is discharged above the pair of cooling blowers 30L, 30R, not along the spinning direction A, so that the filament aggregate 3 can be efficiently cooled.

The ejector 40 is an open type, and ejects the driving fluid, high-pressure air F, with a component in the spinning direction A into the body 42, generating a low-pressure area within the body 42. This generated low-pressure area draws the filament assembly 3 into the body 42, where it is stretched in the spinning direction A together with the high-pressure air F.

The collecting conveyor 50 comprises a collecting belt 51, first to fourth rolls 55 to 58 that are wound around the apex of the inverted trapezoidal orbit of the collecting belt 51, and a suction box 59 that is arranged below the collecting belt 51 on the upper orbit. The collecting belt 51 moves clockwise around the orbit in the orbit direction C as at least one of the first to fourth rolls 55 to 58 rotates. The filament aggregate 3 drawn from the ejector 40 is directly deposited to a predetermined thickness on the collecting belt 51 of the collecting conveyor 50 and is transported to the heat embossing roll 60 in the transport direction B.

The thermal embossing roll 60 comprises a pair of cylindrical rolls with an uneven cylindrical surface heated to a predetermined temperature and a flat cylindrical surface. The pair of cylindrical rolls squeezes the deposited filament aggregate 3, entangling a portion of the filament aggregate 3 with pressure and heat to form a nonwoven fabric 5. This entanglement process is also called the thermal embossing method, and the nonwoven fabric 5 obtained by this method has an embossed pattern on its surface.

In addition to the thermal embossing method, the nonwoven fabric 5 according to this embodiment can employ methods for entangling fibers, such as needle punching, water jetting, ultrasonic waves, or hot air through thermal fusion. The needle punching method is a method in which a needle is inserted into the filament assembly 3 to entangle the filaments. The water jet method is a method in which high-pressure water is sprayed onto the filament assembly 3 to entangle the filaments. The ultrasonic method is a method in which ultrasonic waves are used to melt and entangle some of the filaments. The hot air through method is a method in which hot air is blown onto the filament assembly 3 to melt and entangle some of the filaments.

The winder 70 winds the continuous nonwoven fabric 5 with a specified winding tightness without causing wrinkles.

<About the cooling fan outlet>
Fig. 3 is a perspective view for explaining the air outlets 30AL, 30AR of the pair of cooling fans 30L, 30R shown in Fig. 2. Here, Fig. 3 is a schematic exaggerated view, and differs from the actual arrangement relationship between the pair of cooling fans 30L, 30R and the filament assembly 3.

As shown in FIG. 3, the pair of cooling blowers 30L, 30R are arranged opposite each other in the X-axis direction across the cooling area where the filament aggregate 3 discharged from the spinneret 20 and sucked into the ejector 40 is located. Since the cooling air D is inclined upward and downward from the horizontal direction at the upper and lower ends of the blowing ports 30AL, 30AR, the cooling area is an area that is wider in the vertical direction than the area of the blowing ports 30AL, 30AR of the pair of cooling blowers 30L, 30R when viewed from the X-axis direction. In this cooling area, the filament aggregate 3 is uniformly cooled because the cooling air D is supplied from both sides. In addition, the high-temperature separation gas E discharged from the filament aggregate 3 is exhausted from above the pair of open-type cooling blowers 30L, 30R, not along the spinning direction A.

<Means for imparting crimpability to improve the crimpability of composite fibers>
As described above, the composite fiber of this embodiment employs an eccentric core-sheath type fiber, which allows the composite fiber to be imparted with crimpability by utilizing the degree of promotion of crystallization due to the progress of molecular orientation of the first and second components, that is, the difference in hardness, when the composite fiber is drawn by high-pressure air F in the composite fiber production process (drawing means) (hereinafter also referred to as "first crimpability imparting means (drawing)").

Furthermore, the inventors have discovered that in order to more efficiently impart crimpability to eccentric core-sheath composite fibers, it is important to utilize the differences in melting points and heat shrinkability between the first and second components (hereinafter also referred to as "means for imparting second crimpability (quenching)"). In other words, the inventors have discovered that the crimpability imparted to the composite fibers can be significantly improved by efficiently quenching the composite fibers immediately after they are discharged from the spinneret 20 in the composite fiber production process (cooling means). The means for imparting crimpability, particularly the means for imparting second crimpability (quenching), will be described in detail below.

<Specific means for imparting crimping properties>
Fig. 4 is a cross-sectional view illustrating a pair of cooling fans 30L, 30R taken along the IV-IV cross-sectional line in Fig. 3. The filament aggregate 3 is composed of a plurality of composite fibers 10. The means for imparting crimpability has any one of the following configurations (1) to (5) in order to significantly improve the crimpability imparted to the composite fiber.

(1) As a means for imparting crimping properties, the air outlets 30AL, 30AR of the pair of cooling blowers 30L, 30R are vertically divided into at least three stages (in FIG. 4, there are three stages: upper stages 30L1, 30R1, middle stages 30L2, 30R2, and lower stages 30L3, 30R3), and each is provided with air direction adjustment means L1G-L3G, R1G-R3G that adjust the wind direction of the cooling air D1-D3 to be different. This allows each stage of the pair of air outlets 30AL, 30AR to have a different function (for example, the upper stage is a means for imparting second crimping properties (quenching), and the lower stage is a means for imparting first crimping properties (stretching)).

(2) As a second means for imparting crimpiness (rapid cooling), the wind direction of the cooling air D1 is adjusted by the wind direction adjustment means L1G, R1G at the upper stages 30L1, 30R1 of the pair of blowing ports 30AL, 30AR, and the cooling start point c is positioned between the lower surface 20DL of the spinneret 20 (nozzle 21) and the a-a line 30UL connecting the upper ends a (see FIG. 4) of the pair of blowing ports 30AL, 30AR, as described in detail below. This prevents the cooling air D1 from being blown over a wide area of the spinneret 20, and the spinneret 20 from being overcooled, thereby suppressing adverse effects on the molten resin. Furthermore, the initial eccentric core-sheath type composite fiber that has just been discharged from the spinneret 20 can be efficiently quenched, and the difference in melting point, heat shrinkability, etc. in the composite fiber can be utilized to impart crimpiness to the composite fiber.

Here, the cooling start point c in this embodiment means the intersection c between the wind direction of the cooling air D1 at the upper end a of the pair of blowers 30AL, 30AR (see FIG. 4) and the perpendicular bisector of the spinneret 20. In other words, it indicates the most upstream position on the perpendicular bisector of the spinneret 20 where the cooling of the composite fiber is started by the pair of cooling fans 30L, 30R. In this embodiment, as shown in FIG. 4, the wind direction of the cooling air D1 from the upper stage 30L1 of one blower 30AL and the wind direction of the cooling air D1 from the upper stage 30R1 of the other blower 30AR intersect at the same intersection c (cooling start point) on the perpendicular bisector of the spinneret 20, so that the eccentric core-sheath composite fiber can be quenched more efficiently. However, this is not limiting, and the direction of the cooling air D1 from the upper stage 30L1 of one of the air outlets 30AL and the direction of the cooling air D1 from the upper stage 30R1 of the other air outlet 30AR may intersect at different intersections on the perpendicular bisector of the spinneret 20.

(3) As the first means for imparting crimpiness (stretching), the direction of the cooling air D3 is adjusted by the wind direction adjustment means L3G, R3G at the lower stages 30L3, 30R3 of the pair of air outlets 30AL, 30AR, and the cooling end point f is positioned below the line b-b 30DL connecting the lower ends b (see FIG. 4) of the pair of air outlets 30AL, 30AR, as described in detail below. This allows the traction force of the cooling air D3 to be used as a stretching means in addition to the traction force of the ejector 40, and the degree of crystallization promotion due to the progress of molecular orientation in the composite fiber, that is, the difference in hardness, to be utilized to impart crimpiness to the composite fiber.

Here, the cooling end point f in this embodiment means the intersection point f between the wind direction of the cooling air D3 at the lower end b (see FIG. 4) of the pair of blowing ports 30AL, 30AR and the perpendicular bisector of the spinneret 20 (nozzle 21). In other words, it indicates the most downstream position on the perpendicular bisector of the spinneret 20 where the cooling of the composite fiber is terminated by the pair of cooling fans 30L, 30R. In this embodiment, as shown in FIG. 4, the wind direction of the cooling air D3 from the lower stage 30L3 of one blowing port 30AL and the wind direction of the cooling air D3 from the lower stage 30R3 of the other blowing port 30AR intersect at the same intersection point f (cooling end point) on the perpendicular bisector of the spinneret 20, so that the eccentric core-sheath type composite fiber can be pulled more efficiently. However, this is not limited to the above, and the direction of the cooling air D3 from the lower stage 30L3 of one of the air outlets 30AL and the direction of the cooling air D3 from the lower stage 30R3 of the other air outlet 30AR may intersect at different intersections on the perpendicular bisector of the spinneret 20.

(4) As a second means for imparting crimpiness (rapid cooling), the cooling air D1 from the upper tier 30L1, 30R1 of the pair of blowing ports has a higher wind speed and a lower temperature than the cooling air D3 from the lower tier 30L3, 30R3. This allows the initial eccentric core-sheath composite fiber that has just been discharged from the spinneret 20 to be efficiently quenched, and the differences in the melting points and thermal shrinkage properties of the composite fibers to be utilized to impart crimpiness to the composite fiber.

In this embodiment, the wind speed of the cooling air D1 is preferably 0.5 to 1.2 (m/sec), and more preferably 0.8 to 1.0 (m/sec). The temperature of the cooling air D1 is preferably 10 to 30 (°C), and more preferably 15 to 30 (°C).

(5) As the first means for imparting crimpiness (stretching) and the second means for imparting crimpiness (quenching), the wind direction adjustment means L1G-L3G, R1G-R3G provided at each stage of the pair of air outlets 30AL, 30AR discretely or continuously changes the wind direction of the cooling air D1-D3 from a direction inclined upward from the horizontal to a direction inclined downward from the horizontal so that the cooling air D1-D3 does not interfere with each other as it moves from the upper stage 30L1, 30R1 of the pair of air outlets 30AL, 30AR to the lower stage 30L3, 30R3. This allows the cooling air D1-D3 to be used efficiently without cancelling each other out. Specifically, by using the cooling air D1 to more efficiently quench the initial eccentric core-sheath composite fiber that has just been discharged from the spinneret 20, it is possible to impart crimping properties to the composite fiber by utilizing the differences in melting point and heat shrinkage properties of the composite fiber. In addition, by using the cooling air D3, it is possible to impart crimping properties to the composite fiber by utilizing the degree of promotion of crystallization due to the progress of molecular orientation in the composite fiber, that is, the difference in hardness.

Here, the wind direction adjustment means L2G, R2G provided in the middle stages 30L2, 30R2 of a pair of air outlets 30AL, 30AR in this embodiment are adjusted so that the cooling air D2 faces the same wind direction in the horizontal direction as shown in Figure 4, but the direction of the same wind direction is not limited to this. For example, by having the cooling air D2 have the same wind direction facing the upward side, it can function as a second crimping means (quenching) like the cooling air D1. Also, for example, by having the cooling air D2 have the same wind direction facing the downward side, it can function as a first crimping means (stretching) like the cooling air D3. In addition, in this embodiment, the airflow direction adjustment means L1G-L3G, R1G-R3G in each stage of the pair of air outlets 30AL, 30AR each have the same airflow direction (the upper stage is inclined upward from the horizontal, the middle stage is horizontal, and the lower stage is inclined downward from the horizontal), but the airflow directions of the cooling air in each stage may be different so as not to interfere with each other.

<Comparative evaluation of cooling air direction>
In the comparative evaluation of the wind direction of the cooling air in each of the examples of the present invention, Example 1 to Example 5, seven parameters related to physical properties were compared with Comparative Example 1 and Comparative Example 2. The comparative evaluation is shown in Table 1 below. Here, as a common condition in the comparative evaluation, the filament is an eccentric core-sheath type composite fiber, and the material of the filament is polypropylene resin. In addition, the outlets 30AL and 30AR in the pair of cooling blowers 30L and 30R are divided into three stages in the vertical direction (in FIG. 4, the upper stage 30L1 and 30R1, the middle stage 30L2 and 30R2, and the lower stage 30L3 and 30R3). The cooling air D1-D3 in each stage of the pair of outlets 30AL and 30AR have the same wind direction. Here, the cooling air D2 from the middle stage 30L2 and 30R2 of the pair of outlets 30AL and 30AR has the same wind direction in the horizontal direction. Furthermore, the vertical distance H1 from the spinneret 20 to the upper end a (see FIG. 4) of the pair of blowout ports 30AL, 30AR was set to 72.17 (mm), and the horizontal distance W from each of the blowout ports 30AL, 30AR to the perpendicular bisector of the spinneret 20 was set to 125 (mm). The heights H2-H4 of the respective stages 30L1-30L3, 30R1-30R3 of the pair of blowout ports 30AL, 30AR were each set to 200 (mm), and the length (not shown) of each stage 30L1-30L3, 30R1-30R3 of the pair of blowout ports 30AL, 30AR in the Y-axis direction was set to 4.2 (m). In addition, the wind speeds of the cooling airs D1-D3 were set to 0.8 (m/s), 1.0 (m/s), and 1.2 (m/s). The temperatures of the cooling airs D1-D3 are set to 25.0 (° C.), 15.0 (° C.), and 10.0 (° C.), respectively.

<Evaluation of thread breakage resistance>
When filaments break, they appear as clumps of filaments in the nonwoven fabric 5. Therefore, the resistance to breakage was evaluated by measuring the number of clumps (protruding) filaments per ^120,000 m2 of the area of the nonwoven fabric 5, i.e., the number of defects, using a defect detector (SmartView automatic defect inspection system manufactured by COGNEX Corporation). If the number of defects was six or more, the occurrence of thread breakage was high, so it was marked as "X", if the number of defects was three or more but less than six, the occurrence of thread breakage was low, so it was marked as "△", and if the number of defects was less than three, the occurrence of thread breakage was not high, so it was marked as "O".

<Distance L (mm) from the bottom surface of the spinneret to the cooling start point>
The distance L (mm) from the lower surface 20DL of the spinneret 20 to the cooling start point c indicates the distance L (mm) from the lower surface 20DL of the spinneret 20 to the intersection c (cooling start point) between the wind direction of the cooling air D1 at the most upstream side of the pair of blowing ports 30AL, 30AR and the perpendicular bisector of the spinneret 20, with the lower surface 20DL of the spinneret 20 being the reference line, and the downward direction is a positive value. Here, the wind direction of the cooling air D1 from the upper stage 30L1 of the pair of blowing ports 30AL and the wind direction of the cooling air D1 from the upper stage 30R1 of the pair of blowing ports 30AR intersect at the same intersection c on the perpendicular bisector of the spinneret 20. The distance L (mm) from the lower surface 20DL of the spinneret 20 to the cooling start point c is a parameter that affects the "composite fiber crimp rate" and "difficulty of yarn breakage".

In this embodiment, the distance L (mm) from the lower surface 20DL of the spinneret 20 to the cooling start point c (see Table 1) is preferably 0 to 72.17 (mm), that is, the cooling start point c is preferably located between the lower surface 20DL of the spinneret 20 and the a-a line 30UL connecting the upper ends a (see FIG. 4) of the pair of blowout ports 30AL, 30AR. Here, if the intersection distance L (mm) is 0 (mm) or more, the spinneret 20 is prevented from being overcooled by the cooling air D1, which adversely affects the molten resin, and the "evaluation of the resistance to thread breakage" can be improved. On the other hand, if the intersection distance L (mm) is 72.17 (mm) or less, the initial eccentric core-sheath type composite fiber just discharged from the spinneret 20 is efficiently quenched, and the differences in the melting point, heat shrinkability, etc. of the composite fiber are significantly expressed, and the "shrinkage rate of the composite fiber" can be improved.

<Regarding the angle α (°) of the cooling air at the most upstream side>
The angle α (°) of the cooling air D1 on the most upstream side is the angle α (°) of the cooling air D1 on the most upstream side with respect to the perpendicular bisector of the spinneret 20, that is, one of the interior angles of a rectangle connecting the cooling start point c, the cooling end point f, the upper end a of one of the outlets 30AL (see FIG. 4), and the lower end b of one of the outlets 30AL (see FIG. 4) shown in FIG. 4. The angle α (°) of the cooling air D1 on the most upstream side is a parameter that affects the "crimp rate of the composite fiber" and the "resistance to yarn breakage."

In this embodiment, it is preferable that the angle α (°) of the cooling air D1 on the most upstream side (see Table 1) is 60 to 90 (°), that is, the cooling start point c is located between the lower surface 20DL of the spinneret 20 and the a-a line 30UL connecting the upper ends a (see FIG. 4) of a pair of blowout ports 30AL. Here, if the angle α (°) of the cooling air D1 on the most upstream side is 60 (°) or more, the spinneret 20 is not overcooled by the cooling air D1, so that adverse effects on the molten resin can be suppressed and the "evaluation of resistance to thread breakage" can be improved. On the other hand, if the angle α (°) of the cooling air D1 on the most upstream side is 90 (°) or less, the initial eccentric core-sheath type composite fiber just discharged from the spinneret 20 can be efficiently quenched, and the "shrinkage rate of the composite fiber" and the "evaluation of resistance to thread breakage" can be improved.

<Regarding the angle β (°) of the cooling air at the most downstream side>
The angle β (°) of the cooling air D3 at the most downstream side refers to the angle β (°) of the cooling air D3 at the most downstream side with respect to the perpendicular bisector of the spinneret 20, that is, one of the interior angles of a rectangle connecting the cooling start point c, the cooling end point f, the upper end a of one of the outlets 30AL (see FIG. 4), and the lower end b of one of the outlets 30AL (see FIG. 4) shown in FIG. 4. This angle β (°) of the cooling air D3 at the most downstream side is a parameter that affects the "spinning speed (m/min) of the ejector," the "fiber diameter of the composite fiber," and the "crimp rate of the composite fiber."

In this embodiment, the angle β (°) of the cooling air D3 at the most downstream side (see Table 1) is preferably 60 to 90 (°). Here, if the angle β (°) of the cooling air D3 at the most downstream side is 60 (°) or more and 90 (°) or less, the wind direction of the cooling air D3 can be actively directed toward the spinning direction A of the ejector 40, and the traction force of the cooling air D3 can be used as a stretching means in addition to the traction force of the ejector 40, thereby improving the "ejector spinning speed (m/min)" and making the "fiber diameter of the composite fiber" finer. Furthermore, the first crimping means (stretching) can improve the "crimp rate of the composite fiber".

<Spinning speed (m/min)>
The spinning speed (m/min) is the running speed of the filament aggregate 3 sucked into the ejector 40, and is close to the speed of the high-pressure air F, which is the driving fluid. The spinning speed S (m/min) is calculated by Q×9000/D, where Q represents the single-hole discharge rate (g/min) and D represents the fiber diameter (denier) of the composite fiber.

In this embodiment, the spinning speed (m/min) (see Table 1) is preferably 3000 (m/min) or more, and more preferably 4000 (m/min) or more. By setting the spinning speed to 3000 (m/min) or more, the molecular orientation of the yarn is easily promoted and crystallization is promoted, making it possible to reduce the diameter of high-strength fibers and impart crimping properties to the composite fibers.

<Fiber diameter (μm, denier) of composite fibers>
Using an electron microscope (S-3500N manufactured by Hitachi, Ltd.), a photograph of the composite fiber 10 was taken at a magnification of 1000 times. 100 fibers were randomly selected from the composite fibers 10, the fiber diameters (μm) of the selected composite fibers were measured, and the average value of the 100 fibers was calculated. The fiber diameter D (denier) of the composite fiber was calculated from 0.9×100×π×ρ×(fiber diameter of composite fiber (μm)/200) ² , where ρ represents density (g/ ^cm3 ) (0.91: density of polypropylene resin in this comparative evaluation).

<Concerning the crimp rate (%) of composite fibers>
The crimp percentage (%) of the composite fiber was determined by measuring the crimp percentage (%) of the composite fiber obtained by the spunbond nonwoven fabric manufacturing apparatus 100, i.e., the composite fiber 10 that was spun, cooled, and stretched, based on the initial load and the length when the load was applied, in accordance with Japanese Industrial Standard JIS L1015, and calculating the average value for 20 measurements.

<Comparative evaluation results for cooling air direction>
As is clear from a comparison of the evaluations of Examples 1 to 5, when the distance L (mm) from the lower surface 20DL of the spinneret 20 to the cooling start point c is 0 to 72.17 (mm), in other words, when the angle α (°) of the cooling air on the most upstream side is 60 to 90 (°), the "evaluation of resistance to yarn breakage" is "○" or higher, and the "crimp rate of composite fiber" is 18 (%) or higher, and it was concluded that each can be improved.

Here, if the angle β (°) of the cooling air on the most downstream side is 60 to 90 (°), the "fiber diameter of the composite fiber" will be 11 (μm) or less, making it possible to further fine the composite fiber, and the "crimp rate of the composite fiber" will be 20 (%) or more, making it possible to further improve the crimpability (see Examples 2 to 4).

In contrast to the above, in Comparative Examples 1 and 2, the distance L (mm) from the bottom surface 20DL of the spinneret 20 to the cooling start point c, i.e., the angle α (°) of the cooling air on the most upstream side, is outside the preferred range, so the "evaluation of resistance to thread breakage" is "△" or lower, and the "composite fiber shrinkage rate" is 10% or lower, which is a decrease. In particular, in Comparative Example 1, thread breakage occurs very frequently, causing clogging of the ejector 40 and insufficient embossing, making it impossible to produce a nonwoven fabric, so the "fiber diameter of the composite fiber" and the "composite fiber shrinkage rate" are rated as "-" (immeasurable).

＜Other＞
The present invention is not limited to the above-described embodiments, examples, and modified examples, and can be modified or changed as appropriate without departing from the technical concept of the present invention.

1 First component 2 Second component 3 Filament aggregate 5 Nonwoven fabric 10 Composite fiber (filament)
11 First extruder (spinning means)
12 Second extruder (spinning means)
20 Spinneret (spinning means)
20DL: Lower surface of spinneret 21: Nozzle 30L, 30R: Cooling blower (cooling means)
30AL, 30AR Air outlets 30L1, 30R1 Upper stage of pair of air outlets 30L2, 30R2 Middle stage of pair of air outlets 30L3, 30R3 Lower stage of pair of air outlets 30UL Straight line a-a 30DL connecting upper ends of pair of air outlets Straight line bb connecting lower ends of pair of air outlets 40 Ejector (extension means)
100 Spunbond nonwoven fabric manufacturing apparatus c Cooling start point D1 Cooled air from the upper stage of the pair of blowing ports D2 Cooled air from the middle stage of the pair of blowing ports D3 Cooled air from the lower stage of the pair of blowing ports f Cooling end point H1 Vertical distance H2 from the spinneret to the upper end of the pair of blowing ports Height H3 of the upper stage of the pair of blowing ports Height H4 of the middle stage of the pair of blowing ports Height L of the lower stage of the pair of blowing ports Distance L1G, R1G from the bottom surface of the spinneret to the cooling start point Air direction adjustment means L2G, R2G of the upper stage of the pair of blowing ports Air direction adjustment means L3G, R3G of the middle stage of the pair of blowing ports Air direction adjustment means W of the lower stage of the pair of blowing ports Horizontal distance α from the blowing port to the vertical bisector of the spinneret Angle β of the cooling air on the most upstream side Angle β of the cooling air on the most downstream side

Claims (12)

A spinning means for extruding the molten thermoplastic resin from a spinneret as a filament aggregate composed of filaments;
a stretching means for aerodynamically stretching the filament assembly;
a cooling means disposed between the spinning means and the drawing means for supplying cooling air to the filament assembly to cool it;
Equipped with
The filament is an eccentric core-sheath type composite fiber including a first component which is a core component and a second component which is a sheath component,
The cooling means has a pair of blowing ports sandwiching the filament assembly,
Each of the pair of air outlets is divided into at least three stages in the vertical direction,
Each stage of the air outlet is provided with a wind direction adjusting means for adjusting the direction of the cooling air so that each stage has a different wind direction,
The apparatus for manufacturing an eccentric core-sheath nonwoven fabric is characterized in that it is equipped with a crimping means that imparts crimping property to the filaments by using the air direction adjustment means to position the cooling starting point , which is the intersection of the air direction of the cooling air at the upper end of the outlet and the perpendicular bisector of the spinneret, within an area including a boundary defined by a straight line connecting the upper ends of the pair of outlets and the lower surface of the spinneret. The manufacturing device for eccentric core-sheath nonwoven fabric according to claim 1, characterized in that the angle α of the cooling air at the upper end of the blowing port relative to the perpendicular bisector of the spinneret is 60 to 90 (°). The manufacturing device for eccentric core-sheath nonwoven fabric according to claim 1 or 2, characterized in that the angle β of the cooling air at the lower end of the blowing port relative to the perpendicular bisector of the spinneret is set to 60 to 90 (°). The manufacturing device for eccentric core-sheath nonwoven fabric according to any one of claims 1 to 3, characterized in that the cooling air from the upper part of the air outlet has a higher wind speed and a lower temperature than the cooling air from the lower part of the air outlet. The manufacturing device for eccentric core-sheath nonwoven fabric according to any one of claims 1 to 4, characterized in that the air direction adjustment means provided at each stage of the air outlet discretely or continuously changes the air direction of the cooling air from a direction inclined upward from the horizontal direction to a direction inclined downward from the horizontal direction as it moves from the upper stage of the air outlet to the lower stage of the air outlet so that the cooling air does not interfere with each other. The first component and the second component each contain a thermoplastic resin as a main component,
The first component contains a long chain branched polyolefin resin,
6. The apparatus for producing an eccentric core-sheath nonwoven fabric according to claim 1, wherein the long chain branching polyolefin resin has a melt flow rate of 4 g/10 min or more as measured in accordance with ASTM D1238 at a load of 2.16 kg and a temperature of 230° C. The manufacturing apparatus for an eccentric core-sheath nonwoven fabric according to claim 6, characterized in that the first component contains the long-chain branched polyolefin resin in an amount of 0.5% by mass or more and 10% by mass or less based on the total solid content of the first component. The eccentric sheath-core nonwoven fabric manufacturing apparatus according to claim 6 or 7, characterized in that the eccentric sheath-core composite fiber contains the first component in an amount of 10% by mass or more and 40% by mass or less based on the total solid content of the eccentric sheath-core composite fiber. The manufacturing device for an eccentric core-sheath nonwoven fabric according to any one of claims 6 to 8, characterized in that the first component and the second component each contain a thermoplastic resin in an amount of 90% by mass or more and 100% by mass or less based on the total solid content of each component. The manufacturing device for eccentric core-sheath nonwoven fabric according to any one of claims 6 to 9, characterized in that the first component and the second component each have polypropylene as a main component. The manufacturing apparatus for an eccentric core-sheath nonwoven fabric according to any one of claims 6 to 10, characterized in that the first component is mainly composed of polypropylene, and the long-chain branched polyolefin resin is long-chain branched polypropylene. At least one of the first component and the second component contains the following a) to g):
a) the mesopentad fraction [mmmm] is 30 mol% or more and 80 mol% or less;
b) the racemic pentad fraction [rrrr] and [1-mmmm] satisfy the relationship [rrrr]/[1-mmmm]≦0.1;
c) the racemic-mesoracemic-meso pentad fraction [rmrm] is greater than 2.5 mol%;
d) the mesotriad fraction [mm], the racemic triad fraction [rr], and the triad fraction [mr] satisfy the relationship of [mm] × [rr] / [mr] 2 ≦ 2.0;
e) the weight average molecular weight [Mw] is 10,000 or more and 200,000 or less;
f) the weight average molecular weight [Mw] and the number average molecular weight [Mn] satisfy the relationship of the molecular weight distribution [Mw]/[Mn]≦4;
g) the amount of extractables with boiling diethyl ether is 0% by mass or more and 10% by mass or less based on the total solid content of the low crystalline polyolefin resin;
The apparatus for producing an eccentric core-sheath nonwoven fabric according to any one of claims 1 to 11, characterized in that the low crystalline polyolefin resin satisfying the above condition is contained in an amount of 5 mass% or more and 50 mass% or less based on the total solid content.

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