JP7107343B2 - Long-fiber nonwoven fabric and method for producing long-fiber nonwoven fabric - Google Patents

Description

TECHNICAL FIELD The present invention relates to a long-fiber nonwoven fabric and a method for producing a long-fiber nonwoven fabric.

Patches, bandages, and the like used for medical purposes need to follow the movement of the skin caused by the movement of joints and the like. In addition, high bulk density is required in order to prevent swelling from the ends during use and to obtain sufficient efficacy.

As a nonwoven fabric that can be used for such applications, Patent Document 1 discloses a nonwoven fabric made of two-component polymers of polybutylene terephthalate and polyethylene terephthalate, in which long fibers having crimps are fused and fixed in intermittent regions with a low melting point component. It has an apparent density of 0.10 g / cm ³ or more, a strength at 50% elongation in both the vertical and horizontal directions of 150 g / cm or less, and an elongation recovery rate at 50% elongation of 50% or more. Certain long fiber nonwovens are disclosed.

In addition, Patent Document 2 includes short fibers made of composite fibers in which specific copolymerized polyethylene terephthalate (A) and polyethylene terephthalate (B) are joined side-by-side, and has an elongation rate of 60% or more and an elongation recovery rate of 55%. % or higher.

JP-A-07-042061 JP 2013-044070 A

As described above, long fiber nonwoven fabrics composed of two-component polymers of polybutylene terephthalate and polyethylene terephthalate and nonwoven fabrics containing short fibers composed of two components of polyethylene terephthalate and copolymerized polyethylene terephthalate are conventionally known. On the other hand, a long-fiber nonwoven fabric composed of two components, polyethylene terephthalate and copolymerized polyethylene terephthalate, has not been known in the past.

Conventionally, as a method for producing a long-fiber nonwoven fabric, as disclosed in Patent Document 1, a long-fiber web collected on a net is subjected to crimp development treatment, and then crimps are developed. A method is known in which a long fiber web is subjected to a thermocompression bonding treatment using an embossing roll, and is fused and fixed in intermittent regions with a low-melting-point component.

However, long fiber webs containing copolymerized polyethylene terephthalate are susceptible to crimp shrinkage due to heat. Therefore, in conventional manufacturing methods such as embossing at high temperature, wrinkles occur due to rapid shrinkage, and it is impossible to obtain a long-fiber nonwoven fabric with high bulk density and excellent stretchability. Can not.

The present invention has been made in view of the above-described problems, and an object thereof is to provide a long fiber nonwoven fabric containing polyethylene terephthalate and a copolymer polyester, yet having a high bulk density and excellent stretchability. To provide a fibrous nonwoven fabric. Moreover, it is providing the manufacturing method of the said filament nonwoven fabric.

The present inventors conducted extensive research on long-fiber nonwoven fabrics containing polyethylene terephthalate and copolymerized polyester. As a result, the present inventors have found that a long-fiber nonwoven fabric having a high bulk density and excellent stretchability can be obtained by adopting a novel production method, and have completed the present invention.

That is, the present invention provides the following.
(1) It is composed of bicomponent conjugate spun filaments containing polyethylene terephthalate and copolyester,
Apparent density is 0.1 g / cc or more,
A filament nonwoven fabric having a 10% elongation recovery rate of 65% or more.

As described above, long-fiber webs containing copolyester are prone to crimp shrinkage due to heat. A fibrous nonwoven fabric could not be obtained. On the other hand, in the present invention, as will be described in detail later, a long fiber web containing a copolyester is temporarily pressure-bonded, and then the temporarily pressure-bonded long fiber web is subjected to a crimping process, whereby the bulk density is high, Moreover, it has become possible to obtain a long-fiber nonwoven fabric having excellent stretchability.
Thus, according to the present invention, a long-fiber nonwoven fabric containing polyethylene terephthalate and copolymerized polyester, having an apparent density of 0.1 g/cc or more, and a 10% elongation recovery rate of 65% or more can be provided. Since it has an apparent density of 0.1 g/cc or more, even if it rubs against clothing etc. when used as a patch or bandage, it is less susceptible to friction and does not cause swelling during use. can be prevented. In addition, since the stretch recovery rate of 10% is 65% or more, the stretchability is excellent, and the feeling of use is good when used as a patch or a bandage.

(2) In the configuration of (1), the long fibers are preferably crimped yarns.

When the long fibers are crimped yarns, more excellent stretchability can be obtained.

(3) In the configuration of (1) or (2), the long fibers preferably have a core-sheath structure.

When the long fibers have a core-sheath structure, they can be preferably crimped during production.

(4) In the configuration of (3) above, it is preferable that the center of the core component of the core-sheath structure is eccentric by 2% or more.

In the core-sheath structure, if the center of the core component is eccentric by 2% or more, crimping can be performed more favorably during production.

(5) In the configuration of (1) or (2), the long fibers preferably have a side-by-side structure.

When the long fibers have a side-by-side structure, they can be preferably crimped during production.

(6) In the configurations (1) to (5), it is preferable that no mechanical entanglement treatment is applied.

The long-fiber nonwoven fabric according to the present invention is obtained by temporarily pressing a long-fiber web containing a copolyester and then crimping the temporarily-bonded long-fiber web, as will be described in detail later. Amorphous polyester has a property that it is difficult to be adhered up to around 130° C., and is less likely to be restrained by adhesion points. And it can be made to adhere|attach in the state by which expansion-contraction was expressed. Therefore, no mechanical interlacing treatment is required. In the case of a configuration in which no mechanical entanglement treatment is applied, it can be manufactured at low cost. In addition, compared with the case where needle punching is employed as the mechanical entangling treatment, it is possible to avoid the risk of needle contamination.

(7) In the configurations of (1) to (6) above, the copolymer polyester has terephthalic acid as the dicarboxylic acid component and 50 to 85 mol% of ethylene glycol and 15 to 50 mol% of neopentyl glycol as the glycol component. Preferably.

When the dicarboxylic acid component of the copolymer polyester is terephthalic acid and the glycol component is 50 to 85 mol % of ethylene glycol and 15 to 50 mol % of neopentyl glycol, the crystallinity moderately decreases and is suitable for long-fiber nonwoven fabrics. crimp can be expressed.

In addition, the present invention provides the following.
(8) A step A in which the molten polyethylene terephthalate and copolyester are extruded from a spinneret, cooled and solidified, then pulled and drawn by an ejector to form bicomponent conjugate spun filaments;
a step B of collecting the long fibers obtained in the step A to form a long fiber web;
a step C of temporarily crimping the long fiber web;
A method for producing a filament nonwoven fabric, characterized by comprising a step D of crimping the temporarily crimped filament web.

Since a long fiber web containing a copolyester tends to crimp and shrink due to heat, it is difficult to obtain a long fiber nonwoven fabric having a high bulk density and excellent stretchability by a conventional method for producing a long fiber nonwoven fabric. I couldn't. On the other hand, in the present invention, after temporarily press-bonding a long fiber web containing a copolymer polyester, the temporarily press-bonded filament web is subjected to a crimping process to achieve a high bulk density and excellent stretchability. It became possible to obtain a long fiber nonwoven fabric having

(9) In the configuration of (8), the step A uses an eccentric core-sheath nozzle as the spinneret, and mixes the polyethylene terephthalate as a core component and the copolymer polyester as a sheath component with the eccentric core. It is preferable to include the step A-1 of discharging from the sheath nozzle.

An eccentric core-sheath nozzle is used as the spinneret, and the polyethylene terephthalate as the core component and the copolyester as the sheath component are discharged from the eccentric core-sheath nozzle, followed by a crimping step (step D). WHEREIN: It becomes possible to apply crimping suitably.

(10) In the configuration of (8), the step A uses a side-by-side nozzle as the spinneret, and the polyethylene terephthalate and the copolyester are laminated side-by-side in the fiber length direction. It is preferable to include step A-2 of discharging from a nozzle.

A side-by-side nozzle is used as the spinneret, and when the polyethylene terephthalate and the copolyester are discharged from the side-by-side nozzle so as to bond the polyethylene terephthalate and the copolyester in a side-by-side manner in the fiber length direction, it is suitable for the subsequent crimping step (step D). crimping can be applied to the

(11) In the configurations of (8) to (10) above, the copolymerized polyester contains terephthalic acid as the dicarboxylic acid component and 50 to 85 mol% of ethylene glycol and 15 to 50 mol% of neopentyl glycol as the glycol component. Preferably.

When the dicarboxylic acid component of the copolymer polyester is terephthalic acid and the glycol component is 50 to 85 mol % of ethylene glycol and 15 to 50 mol % of neopentyl glycol, the crystallinity moderately decreases and is suitable for long-fiber nonwoven fabrics. crimp can be expressed.

According to the present invention, it is possible to provide a long-fiber nonwoven fabric containing polyethylene terephthalate and copolymerized polyester, yet having a high bulk density and excellent stretchability. Moreover, the manufacturing method of the said long-fiber nonwoven fabric can be provided.

Embodiments of the present invention will be described below.

[Long fiber non-woven fabric]
The long fiber nonwoven fabric according to this embodiment is
It is composed of long fibers of a bicomponent composite spun yarn containing polyethylene terephthalate and copolyester,
It has an apparent density of 0.1 g/cc or more and a 10% elongation recovery rate of 65% or more.

The long fibers constituting the long fiber nonwoven fabric are composed of two-component conjugate spun yarns containing polyethylene terephthalate and copolyester.

As used herein, the term "long fiber" refers to a fiber whose length is endless when spun (endless continuous fiber). However, when the finally obtained long-fiber nonwoven fabric is cut to a predetermined length, the length of the long-fiber nonwoven fabric is the same as the length of the long-fiber nonwoven fabric. On the other hand, short fibers refer to fibers contained in the nonwoven fabric whose length is less than the length of the nonwoven fabric. That is, a long-fiber nonwoven fabric is a nonwoven fabric composed of fibers (long fibers) having the same length as the length of the nonwoven fabric, and a short-fiber nonwoven fabric is a fiber (short fiber) shorter than the length of the short-fiber nonwoven fabric. A nonwoven fabric composed of

Since the long fibers contain polyethylene terephthalate, they are superior in mechanical strength, heat resistance, shape retention, etc., compared to the case of using resins such as polyethylene and polypropylene. The content of the polyethylene terephthalate in the long fibers is preferably 20% by mass or more and 80% by mass or less, more preferably 30% by mass or more and 70% by mass or less, and still more preferably 40% by mass or more and 60% by mass or less. When the content of the polyethylene terephthalate is within the above numerical range, the mechanical strength, heat resistance, shape retention and the like are excellent. Polyethylene terephthalate is a polyester that exhibits an exothermic peak derived from crystallization and/or an endothermic peak derived from crystal melting in measurement with a differential scanning calorimeter (DSC).

The amorphous polyester is a resin that does not have a distinct crystallization exothermic peak and crystalline melting peak as measured by a differential scanning calorimeter (DSC). Further, the amorphous polyester has a glass transition temperature (Tg) of 50° C. or higher. The glass transition temperature (Tg) is a value determined from the transition point of latent heat when the temperature is raised at a rate of 20° C./min by DSC. By adopting the amorphous polyester having a glass transition temperature (Tg) of 50° C. or higher, good heat resistance can be obtained. That is, in order to improve the heat resistance and impact resistance of the long-fiber nonwoven fabric, the copolyester having a high Tg while being amorphous is employed.
In addition, the copolyester has lower crystallinity than polyethylene terephthalate (homopolymer). Since the long-fiber nonwoven fabric (the long fibers) is a two-component conjugate spun yarn containing polyethylene terephthalate and copolymerized polyester, when heat-treated, a difference in shrinkage occurs due to a difference in crystallinity, and winding occurs. Shrinkage develops.

Examples of the copolymerization component of the copolymer polyester include aromatic dicarboxylic acids such as terephthalic acid and 2,6-naphthalenedicarboxylic acid; Aliphatic dicarboxylic acids; alicyclic dicarboxylic acids such as hexahydroterephthalic acid, and as glycol components, aliphatic glycols such as ethylene glycol, propylene glycol, 1,4-butanediol, neopentyl glycol, and hexamethylene glycol; Aromatic glycols such as bisphenol, 1,3-bis(2-hydroxyethoxy)benzene and 1,4-(hydroxyethoxy)benzene are included. 1 type(s) or 2 or more types can be used for these. The copolymer component is preferably selected within a range in which the Tg of the copolymer polyester can be maintained at 50° C. or higher.

The following (a) to (d) are preferred, and (a) is more preferred for the copolyester.
(a) Copolyester in which the dicarboxylic acid component is terephthalic acid and the glycol component is 50 to 85 mol % of ethylene glycol and 15 to 50 mol % of neopentyl glycol.
(b) Copolyester in which the dicarboxylic acid component is terephthalic acid and the glycol component is 50 to 85 mol % of ethylene glycol and 15 to 50 mol d of 1,4-cyclohexanedimethanol.
(c) Copolyester in which the dicarboxylic acid component is terephthalic acid and the glycol component is 50 to 85 mol % of 1,4-butanediol and 15 to 50 mol % of neopentyl glycol.
(d) Copolyester in which the dicarboxylic acid component is terephthalic acid and the glycol component is 50 to 85 mol % of 1,4-butanediol and 15 to 50 mol % of 1,4-cyclohexanedimethanol.
In the case of (a) and (b) above, the content of ethylene glycol is more preferably 50 to 85 mol %, further preferably 65 to 75 mol %.
In the case of (c) and (d) above, the content of 1,4-butanediol is more preferably 50 to 85 mol %, still more preferably 65 to 75 mol %.
In the cases of (a) and (c) above, the content of neopentyl glycol is more preferably 15 to 50 mol %, more preferably 25 to 35 mol %.
In the cases of (b) and (d) above, the content of 1,4-cyclohexanedimethanol is more preferably 15 to 50 mol %, still more preferably 25 to 35 mol %.
The copolymerized polyesters (a) to (d) have moderately low crystallinity and can develop crimps suitable for long-fiber nonwoven fabrics. Properties such as thermal stability are also preferred.

The content of the copolyester in the long fibers is preferably 20% by mass or more and 80% by mass or less, more preferably 30% by mass or more and 70% by mass or less, and still more preferably 40% by mass or more and 60% by mass or less. When the content of the copolyester is within the above numerical range, crimps can be favorably developed.

The copolymerization method for producing the copolymerized polyester is not particularly limited, and conventionally known methods can be employed.

The long fibers preferably have a core-sheath structure. When the long fibers have a core-sheath structure, they can be preferably crimped during production.

The core-sheath structure preferably has an eccentric fiber cross section. Specifically, the center of the core component is preferably eccentric by 2% or more, more preferably by 3% or more. That is, the eccentricity measured by the method described in Examples is preferably 2% or more, more preferably 3% or more. The greater the eccentricity of the center of the core component, the better.

In the core-sheath structure, it is preferable that the sheath side is made of copolymerized polyester and the core side is made of polyethylene terephthalate, from the viewpoint of obtaining suitable crimps.

It is also preferable that the long fibers have a side-by-side structure in which copolyester and polyethylene terephthalate are bonded together. When the long fibers have a side-by-side structure, they can be preferably crimped during production.

The fiber diameter of the long fibers is preferably 5 to 60 μm, more preferably 10 to 50 μm, still more preferably 12 to 40 μm. When the fiber diameter is 5 µm or more, the spinnability in the spunbond method becomes better, and stable production becomes possible. Further, when the fiber diameter is 60 μm or less, the nonwoven fabric is less likely to be uneven, and when used as a patch, it is possible to suppress exudation of the medicinal ingredient.

The long fiber nonwoven fabric is preferably not mechanically entangled. Examples of the mechanical entangling treatment include entangling treatment by a needle punch method or a water punch method. The case where the mechanical entanglement treatment is not performed is preferable in that it can be manufactured at low cost. Moreover, it is preferable in that it is possible to avoid the risk of contamination of needle needles that may occur when the needle punch method is employed. Also, the water punch method uses a large amount of water and requires a huge amount of energy. Therefore, from the viewpoint of environmental preservation and energy saving, it is preferable that the mechanical entanglement treatment is not performed.

The filament nonwoven fabric has an apparent density of 0.1 g/cc or more, preferably 0.11 g/cc or more, and more preferably 0.13 g/cc or more. The apparent density is preferably as high as possible, but can be, for example, 0.3 g/cc or less, or 0.28 g/cc or less. Since the apparent density is 0.1 g/cc or more, when used as a patch or a bandage, even if it rubs against clothing, etc., it is less likely to be rubbed and may cause swelling during use. can be prevented.

The long-fiber nonwoven fabric has a 10% elongation recovery rate of 65% or more, preferably 70% or more, and more preferably 80% or more. Moreover, although the elongation recovery rate of 10% is preferably as large as possible, it can be, for example, 99.5% or less, or 99.0% or less. Since the 10% elongation recovery rate is 65% or more, the stretchability is excellent, and when used as a patch or a bandage, the feeling of use is good. For example, when applied to a joint such as an elbow, it can follow the movement of the skin in the bent portion, thereby suppressing the occurrence of wrinkles. As a result, peeling caused by wrinkles can be prevented.
In this specification, "10% elongation recovery rate is 65% or more" means that the 10% elongation recovery rate in the MD (machine direction) direction is 65% or more, and the CD (cross direction) direction It means that the elongation recovery rate of 10% in is 65% or more.

To obtain a long-fiber nonwoven fabric having an apparent density of 0.1 g/cc or more and a 10% elongation recovery rate of 65% or more in spite of the conventional long-fiber nonwoven fabric containing polyethylene terephthalate and copolymer polyester. I couldn't. On the other hand, in the present embodiment, the apparent density is increased by a novel manufacturing method, that is, by temporarily press-bonding a filament web containing copolyester and then crimping the temporarily press-bonded filament web. It became possible to achieve an elongation recovery rate of 0.1 g/cc or more and an elongation recovery of 65% or more of 10%.

The long-fiber nonwoven fabric according to the present embodiment has been described above.

Next, a method for manufacturing the long-fiber nonwoven fabric according to this embodiment will be described.

[Manufacturing method of long fiber nonwoven fabric]
The method for producing a long-fiber nonwoven fabric according to this embodiment includes:
A step A in which the melted polyethylene terephthalate and copolyester are extruded from a spinneret, cooled and solidified, then pulled and drawn by an ejector to form a long fiber of bicomponent composite spun yarn;
a step B of collecting the long fibers obtained in the step A to form a long fiber web;
a step C of temporarily crimping the long fiber web;
and a step D of crimping the temporarily crimped filament web.

<Process A>
In the method for producing a long-fiber nonwoven fabric according to the present embodiment, first, melted polyethylene terephthalate and copolyester are extruded from a spinneret, cooled and solidified, then pulled and stretched by an ejector to form two components. Forming long fibers of composite spinning.

This step A can be carried out using a conventionally known two-component spunbond spinning machine. That is, the long fibers can be produced by the spunbond method, which is a direct spinning type production method in which a nonwoven fabric is produced directly from the process of making fibers ((spinning process).

As the polyethylene terephthalate and the copolymer polyester, those described in the section on the long-fiber nonwoven fabric can be employed.

In the step A, spinning is preferably performed at a spinning speed of 3500 m/min or more. That is, the melted polyethylene terephthalate and copolymerized polyester are extruded from a spinneret, cooled and solidified, then pulled and drawn by an ejector at a spinning speed of 3500 m/min or more to form a bicomponent conjugate spun filament. preferably. By setting the spinning speed to 3500 m/min or more, the orientation crystallinity of the polyester terephthalate is increased. When the spinning speed is 3,500 m/min or higher, the orientation of the copolyester also proceeds. However, since the copolyester has low crystallinity, in the subsequent crimping step (heating step in step D), shrinkage of the components on the copolyester side occurs, and crimping is not suitable. Express. The spinning speed is more preferably 3800 m/min or higher, still more preferably 4200 m/min or higher. The spinning speed is preferably 5500 m/min or less, more preferably 5000 m/min or less, from the viewpoint of spinnability.

As used herein, the spinning speed refers to a value obtained by the following formula (1).
V=(10000×Q)/T (1)
Here, V is the spinning speed (m/min), T is the fineness of the single fiber (dtex), and Q is the single hole discharge rate (g/min).

The single hole discharge rate Q is the total of the two components, preferably 0.2 to 5 g/min. By controlling the single-hole discharge rate Q to 0.2 to 5 g/min, the spinning speed V can be easily controlled within a desired range. More preferably 0.3 to 4 g/min, more preferably 0.5 to 3 g/min. The single fiber fineness T (dtex) is a value that represents the mass of a 10,000-meter single fiber in grams.

In the step A, an eccentric core-sheath nozzle is used as the spinneret, and the polyethylene terephthalate as a core component and the copolyester as a sheath component are discharged from the eccentric core-sheath nozzle. preferably included. A conventionally known one can be adopted as the eccentric core-sheath nozzle. An eccentric core-sheath nozzle is used as the spinneret, and the polyethylene terephthalate as the core component and the copolyester as the sheath component are discharged from the eccentric core-sheath nozzle, followed by a crimping step (step D). WHEREIN: It becomes possible to apply crimping suitably.

The step A includes a step A-2 in which a side-by-side nozzle is used as the spinneret, and the polyethylene terephthalate and the copolyester are discharged from the side-by-side nozzle so as to bond the polyethylene terephthalate and the copolyester in a side-by-side manner in the fiber length direction. is also preferred. Conventionally known nozzles can be employed as the side-by-side nozzles. A side-by-side nozzle is used as the spinneret, and when the polyethylene terephthalate and the copolyester are discharged from the side-by-side nozzle so as to bond the polyethylene terephthalate and the copolyester in a side-by-side manner in the fiber length direction, it is suitable for the subsequent crimping step (step D). crimping can be applied to the

In the step A, it is preferable to adopt either the step A-1 or the step A-2.

Regardless of whether step A-1 or step A-2 is adopted, spinning is performed from a spinneret with an orifice diameter of 0.1 to 0.5 mm, and the ejector is 1.5 to 4.0 kg/cm ² . It is preferable to supply dry air at a pressure (jet pressure) of . The orifice diameter of the spinneret is more preferably 0.15 to 0.45 mm, more preferably 0.18 to 0.45 mm. The jet pressure is more preferably 2.0-4.0 kg/cm ² , still more preferably 2.5-3.8 kg/cm ² . By controlling the orifice diameter within the above range, it becomes easier to obtain a desired fiber diameter. Further, by controlling the supply pressure (jet pressure) of the drying air within the above range, it becomes easier to control the spinning speed within the desired range, and it is possible to dry appropriately.

<Process B>
Next, the long fibers obtained in the step A are collected to form a long fiber web (step B). For example, a long fiber web may be formed by collecting the long fibers on a lower conveyor while opening the fibers.

<Process C>
Next, the long fiber web obtained in the step B is temporarily pressure-bonded (step C). The temporary pressure bonding is performed within a temperature range in which the long fiber web does not shrink. Thereby, it becomes possible to convey suitably. The temperature during the temporary pressure bonding is preferably 50°C to 80°C, more preferably 55°C to 75°C, and still more preferably 60°C to 70°C. A flat roll can be used for the temporary pressure bonding. The linear pressure during temporary pressure bonding is preferably 1 to 10 kg/cm, more preferably 3 to 7 kg/cm. When the linear pressure is within the above numerical range, the film can be passed through the process without breakage during transportation.

<Process D>
Next, crimping is applied to the temporarily crimped filament web (step D). The crimped long fibers become crimped yarns. In this embodiment, two or more heating rollers whose temperature can be modulated and whose speed ratio can be changed are used to crimp the filament web while gradually decreasing the speed ratio. The heating roller is set to a temperature at which crimping occurs or higher, and shrinkage also occurs. Since the transport speed ratio is lowered by the amount of contraction accompanying the shrinkage, it is possible to suppress the occurrence of wrinkles and the like due to rapid shrinkage.
The number of the heating rollers is preferably two or more, more preferably four or more. By using a plurality of heating rollers and gradually decreasing the speed ratio, the area of the long fiber web can be reduced according to the amount of shrinkage, and the occurrence of wrinkles can be suppressed. The upper limit of the number of heating rollers is not particularly limited, but from the viewpoint of equipment cost, for example, 12 or less,
10 or less may be used.
The heating temperature (temperature of the heating roller) during crimping is preferably 60 to 150°C, more preferably 70 to 140°C, and even more preferably 80 to 130°C. When the heating temperature is within the above numerical range, crimps can be favorably developed. The conveying speed may be reduced according to the amount of shrinkage of the long fiber web during crimping.
During the crimping process, nipping may be performed as necessary. Nipping is preferably performed during crimping with a heating roller having the highest temperature. Adhesion can be improved by performing nipping during crimping with a heating roller having the highest temperature.

In the above step D, the crimp is applied while being in contact with the heating roller. As a result, it is smooth, has a high apparent density, and can be finished thin.

The method for manufacturing the long-fiber nonwoven fabric according to the present embodiment has been described above.

Hereinafter, the present invention will be described in detail using examples, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded.

(Intrinsic viscosity)
0.1 g of resin (polyethylene terephthalate or copolyester) was weighed, dissolved in 25 ml of mixed solvent of phenol/tetrachloroethane (60/40 (weight ratio)), and measured at 30° C. using an Ostwald viscometer. It measured 3 times and calculated the average value.

(Glass-transition temperature)
According to JIS K7122 (1987), the glass transition temperature of the copolyester was determined at a temperature increase rate of 20°C/min.

(specific gravity)
A density gradient solution made from calcium nitrate tetrahydrate is prepared in a density gradient tube, and a specific gravity float range of 1.29 to 1.5 g/cm ³ is used, and the fiber after jet drawing is put into the density gradient tube. After stabilizing for 4 hours or more, the memory of the floating position was read, and the specific gravity was obtained from the calibration curve of the float.

(Metsuke)
The mass per unit area was measured according to JIS L1913 (2000) 5.2.

(Apparent density (bulk density))
The basis weight and thickness obtained according to JIS-L1913 (2010) 5.2 were converted into weight per 1 cm ³ to obtain bulk density. Specifically, the thickness was measured with a thickness gauge using a terminal of 0.5 g/cm ² , and the bulk density was obtained by dividing the basis weight by the thickness.

(fiber diameter)
5 arbitrary locations on the sample (long-fiber web before temporary pressure bonding) were selected, the diameter of the single fiber was measured at n=20 using an optical microscope, and the average value was obtained.

(fineness (dtex))
The sample (long-fiber fleece before temporary pressure bonding) was selected at 5 arbitrary points, and the single fiber diameter was measured at n=20 using an optical microscope to obtain the average single fiber diameter. Five fibers at the same location were taken out, and the specific gravity of the fibers was measured at n=5 using a density gradient tube to obtain an average specific gravity. Next, the fineness [dtex], which is the fiber weight per 10,000 m, was determined from the single fiber cross-sectional area determined from the average single fiber diameter and the average specific gravity.

(Eccentricity)
A metal plate with holes of 0.5 to 2 mm was prepared. Also, fibers made of nonwoven fabric were cut out and embedded with black fibers. The holes of the metal plate were stuffed with fibers made of nonwoven fabric embedded with black fibers, and both ends were cut with a razor. The radius (R) of the outer circle on the sheath side was measured using an optical microscope connected to a computer installed with software capable of measuring distance. The distance between the center on the core side and the center on the sheath side was measured and defined as the eccentric distance (L). Next, the eccentricity (%) was obtained by the following formula.
(Eccentricity) = (L/R) x 100

(Spinning speed (m/min))
The spinning speed V (m/min) was determined based on the following formula from the fineness T (dtex) and the set single hole discharge rate Q (g/min).
V=(10000×Q)/T

(10% elongation recovery rate)
A sample of 25×150 mm was prepared. Using a constant speed elongation type tensile tester equipped with a self-recording device, the test piece was attached with a grip interval of 50 mm while being pulled by hand to the extent that it did not loosen, and the initial load was set to 0.02 N/25 mm. At this time, "(grip distance) + (extended length when initial load is applied)" was defined as L0. After that, it was stretched to 10% of the gripping distance (5 mm elongation) at a tensile speed of 25 mm/min. The length at this time was defined as L1. After that, immediately after unloading to the initial load at the same speed, the length of the sample was defined as L2. The 10% elongation recovery rate was determined by the following formula. Measured at n=5 in each of the vertical and horizontal directions, and the average value was rounded off to the first decimal place.
10% elongation recovery rate (%) = [(L1-L2) / (L1-L0)] × 100

(Peelability evaluation)
A 140 mm×100 mm non-woven fabric coated with a medical adhesive was applied to the elbows of five subjects, and they were made to wear long-sleeved shirts. In the case of grades 2 to 5, it was judged that peeling was suppressed.
Grade 0: Dropped Grade 1: More than half peeled Grade 2: 1/3 peeled Grade 3: 1/5 peeled Grade 4: Slightly peeled at the edge Grade 5: No peeling

(Example 1)
Using a side-by-side nozzle on a two-component spunbond spinning equipment, polyethylene terephthalate (intrinsic viscosity (iv value): 0.63) and copolymer polyester (dicarboxylic acid component is terephthalic acid, glycol component is ethylene glycol 70 mol% and neo A copolymer containing 30 mol % of pentyl glycol, intrinsic viscosity (iv value): 0.75, Tg: 75° C.) was spun at a mass ratio of 5.5 (polyethylene terephthalate):4.5 (copolyester). I put it out. Spinning was carried out from a spinneret with an orifice diameter of 0.36 mm at a single hole discharge rate of 1.0 g/min. After that, dry air is supplied to the ejector at a pressure of 3.5 kg/cm ² (jet pressure), the fibers are stretched in one step, and the fibers are spread and collected on the lower conveyor to form a long fiber web. got Next, the obtained long-fiber web was temporarily pressure-bonded. The conditions for the temporary pressure bonding were a temporary pressure bonding roll temperature of 60° C. and a linear pressure of 5 kg/cm.
The long fiber web thus obtained had a fiber diameter of 14.5 μm, a spinning speed of 4500 m/min, and a basis weight of 25 g/m ² .

Next, the obtained filament web was crimped while being conveyed by six heating rolls. Specifically, the temperature of each heating roll and the speed ratio of each heating roll were assumed as shown in Table 1. Note that the speed ratio means the speed at which the material is conveyed from the entrance of the first roll to the first roll, and the speed at which the material is discharged from the exit of each roll. During crimping by the fourth roll, pressure was applied by a rubber nip roll.

The obtained nonwoven fabric had a basis weight of 100 g/m ² , a thickness of 0.8 mm, an apparent density of 0.13 g/cc, a 10% elongation recovery rate in the MD direction of 84%, a 10% elongation recovery rate in the CD direction of 87%, The peelability evaluation grade was 5 grades.

(Example 2)
A core-sheath nozzle with an eccentricity of 0.1 mm is used, and a copolymer polyester (a copolymer whose dicarboxylic acid component is terephthalic acid and whose glycol component is 70 mol% ethylene glycol and 30 mol% neopentyl glycol) is applied to the sheath side. , intrinsic viscosity (iv value): 0.75, Tg: 75° C.), a nonwoven fabric was obtained under the same conditions as in Example 1.

The obtained nonwoven fabric had a basis weight of 98 g/m ² , a thickness of 0.75 mm, an apparent density of 0.13 g/cc, a 10% elongation recovery rate in the MD direction of 78%, a 10% elongation recovery rate in the CD direction of 83%, The peelability evaluation grade was 4 grades.

(Example 3)
Polyethylene terephthalate and copolymer polyester (dicarboxylic acid component is terephthalic acid, glycol component is 70 mol% of ethylene glycol and 30 mol% of neopentyl glycol, intrinsic viscosity (iv value): 0.75, Tg: A nonwoven fabric was obtained under the same conditions as in Example 1, except that the ratio of 75° C.) was changed to 6.5:3.5.

The resulting nonwoven fabric had a basis weight of 95 g/m ² , a thickness of 0.9 mm, an apparent density of 0.11 g/cc, a 10% elongation recovery rate in the MD direction of 71%, a 10% elongation recovery rate in the CD direction of 72%, The peelability evaluation grade was 3 grades.

(Example 4)
Polyethylene terephthalate and copolymer polyester (dicarboxylic acid component is terephthalic acid, glycol component is 70 mol% of ethylene glycol and 30 mol% of neopentyl glycol, intrinsic viscosity (iv value): 0.75, Tg: A nonwoven fabric was obtained under the same conditions as in Example 2, except that the ratio of 75° C.) was changed to 6.5:3.5.

The resulting nonwoven fabric had a basis weight of 97 g/m ² , a thickness of 0.92 mm, an apparent density of 0.11 g/cc, a 10% elongation recovery rate in the MD direction of 67%, a 10% elongation recovery rate in the CD direction of 70%, The peelability evaluation grade was 3 grades.

(Example 5)
As the copolyester on the sheath side, a copolymer (intrinsic viscosity (iv value): 0.75, Tg A nonwoven fabric was obtained under the same conditions as in Example 2, except that the temperature was 75° C.).

The obtained nonwoven fabric had a basis weight of 97 g/m ² , a thickness of 0.85 mm, an apparent density of 0.11 g/cc, a 10% elongation recovery rate in the MD direction of 65%, a 10% elongation recovery rate in the CD direction of 67%, The peelability evaluation grade was 3 grades.

(Example 6)
As a copolymer polyester, a copolymer (intrinsic viscosity (iv value): 0.75, Tg: 75°C ) was obtained under the same conditions as in Example 1, except that ) was used.

The resulting nonwoven fabric had a weight of 110 g/m ² , a thickness of 0.8 mm, an apparent density of 0.14 g/cc, a 10% elongation recovery rate in the MD direction of 86%, a 10% elongation recovery rate in the CD direction of 88%, and peelability. The evaluation grade was 5 grades.

(Comparative example 1)
A spunbonded nonwoven fabric was obtained under the same conditions as in Example 1, except that the crimping process was performed by hot air through at 130° C. instead of crimping using a heating roll.

The resulting nonwoven fabric had a weight of 101 g/m ² , a thickness of 1.3 mm, an apparent density of 0.08 g/cc, a 10% elongation recovery rate in the MD direction of 88%, a 10% elongation recovery rate in the CD direction of 89%, and peelability. The evaluation grade was 1 grade.

(Comparative example 2)
Polyethylene terephthalate and copolymer polyester (dicarboxylic acid component is terephthalic acid, glycol component is 70 mol% of ethylene glycol and 30 mol% of neopentyl glycol, intrinsic viscosity (iv value): 0.75, Tg: An attempt was made to obtain a non-woven fabric under the same conditions as in Example 1, except that the weight ratio was 8.5:1.5, but shrinkage due to crimping hardly occurred.

(Comparative Example 3)
As a copolymer polyester, a copolymer (intrinsic viscosity (iv value): 0.75, Tg: 75 ° C. ) was attempted to obtain a nonwoven fabric under the same conditions as in Example 1, but shrinkage due to crimping did not occur.

Claims (11)

It is composed of long fibers of a bicomponent composite spun yarn containing polyethylene terephthalate and copolyester,
Apparent density is 0.1 g / cc or more,
A filament nonwoven fabric having a 10% elongation recovery rate of 65% or more. The long-fiber nonwoven fabric according to claim 1, wherein the long fibers are crimped yarns. 3. The long-fiber nonwoven fabric according to claim 1, wherein the long fibers have a core-sheath structure. 4. The long-fiber nonwoven fabric according to claim 3, wherein the center of the core component of the core-sheath structure is eccentric by 2% or more. The long fiber nonwoven fabric according to claim 1 or 2, wherein the long fibers have a side-by-side structure. The long-fiber nonwoven fabric according to any one of claims 1 to 5, which is not mechanically entangled. 7. The copolymer polyester according to any one of claims 1 to 6, wherein the dicarboxylic acid component is terephthalic acid, and the glycol component is 50 to 85 mol % of ethylene glycol and 15 to 50 mol % of neopentyl glycol. The filament nonwoven fabric described in 1. A step A in which the melted polyethylene terephthalate and copolyester are extruded from a spinneret, cooled and solidified, then pulled and drawn by an ejector to form a long fiber of bicomponent composite spun yarn;
a step B of collecting the long fibers obtained in the step A to form a long fiber web;
a step C of temporarily crimping the long fiber web;
A method for producing a filament nonwoven fabric, characterized by comprising a step D of crimping the temporarily crimped filament web. The step A includes a step A-1 of using an eccentric core-sheath nozzle as the spinneret and discharging the polyethylene terephthalate as the core component and the copolyester as the sheath component from the eccentric core-sheath nozzle. The method for producing a long-fiber nonwoven fabric according to claim 8. The step A includes a step A-2 in which a side-by-side nozzle is used as the spinneret, and the polyethylene terephthalate and the copolyester are discharged from the side-by-side nozzle so as to bond the polyethylene terephthalate and the copolyester in a side-by-side manner in the fiber length direction. The method for producing a long-fiber nonwoven fabric according to claim 8. 11. The copolymer polyester according to any one of claims 8 to 10, wherein the dicarboxylic acid component is terephthalic acid, and the glycol component is 50 to 85 mol % of ethylene glycol and 15 to 50 mol % of neopentyl glycol. 3. The method for producing the long fiber nonwoven fabric according to .