JP2001336033A - Polyester-based conjugate yarn and nonwoven fabric using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain both a polyethylene-based conjugate yarn not dropping card processability, suitably used for a pressure adhesion processing method and a through air adhesion processing method, capable of providing a nonwoven fabric having a soft feeling and exhibiting high tenacity, and the nonwoven fabric using the same. SOLUTION: The polyethylene-based conjugate yarn is characterized in that the yarn in a sheath-core type conjugate yarn composed of a polyethylene-based resin, wherein a first component (core component) is composed of a polyethylene resin having >=0.940 g/cm3 density and a second component (sheath component) comprises a polyethylene resin having <=3.0 Q value (weight-average molecular weight Mw/number-average molecular weight Mn) and polymerized by a metallocene catalyst. This nonwoven fabric is obtained by using the polyethylene-based conjugate yarn.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyethylene composite fiber and a nonwoven fabric using the fiber. More specifically, the present invention relates to a polyethylene-based composite fiber which is flexible, has excellent texture, is bulky and has high strength, a nonwoven fabric using the fiber, a medical article and a sanitary article using the same.

[0002]

2. Description of the Related Art In the medical field, disposable surgical caps, sheets, surgical coverings, surgical gowns and the like made of non-woven fabrics are rapidly spreading. This is to cope with a movement to prevent hospital-acquired infections such as MRSA (methicillin-resistant staphylococci), hepatitis, and HIV (acquired immunodeficiency syndrome). Also, using disposable non-woven products that do not require cleaning can simplify nursing work without deteriorating the quality of nursing, and help to alleviate the labor shortage that is now a serious social problem. Nonwoven fabrics used in the medical field are required to have bacterial barrier properties, penetration resistance, water repellency, lint-free properties, etc., but since they are in direct contact with the human body and are single-use disposables, The feeling of wearing, strength, and cost are also important factors.

[0003] As raw material resins for fibers for use in nonwoven fabrics, polyethylene resins, polypropylene resins and polyester resins are generally used, but nonwoven fabrics used in the medical field are no exception. Such nonwoven fabrics used in the medical field are often sterilized by radiation. However, when irradiated with radiation, the polypropylene resin cuts the polymer chains at the tertiary carbon atom bonding sites, resulting in nonwoven fabrics. The use of such a device that is sterilized by radiation is limited because the strength of the material is significantly reduced. In addition, polyester-based resin does not decrease in strength due to radiation, but the raw material resin is more expensive than polyolefin-based resin, so that it follows the movement of the body and gives strength enough to not break or does not pass through Therefore, when the nonwoven fabric is made to have a high basis weight, the nonwoven fabric becomes hard and the feeling of wearing is poor, and the lightness is lacking due to the characteristics of the raw material resin. Has become. On the other hand, a soft nonwoven fabric can be obtained from the polyethylene resin because the raw material resin is soft. Since it has no tertiary carbon atoms, it has the advantage that the strength of the nonwoven fabric does not decrease due to radiation irradiation, and is therefore excellent as a medical nonwoven fabric material.

[0004] However, conventional polyethylene fibers composed of only a single component can be relatively easily formed into non-woven fabrics by point bonding and calendering using a pressure roll during non-woven fabric processing. Unsuitable, the resulting non-woven fabric lacks flexibility. In order to solve the above-mentioned drawbacks, for example, Japanese Patent Application Laid-Open No. 6-508892 (International Publication No. WO93 / 01334) discloses a copolymer of ethylene and α-olefin (hereinafter referred to as linear Low density polyethylene (L-LDP
E)), a polyethylene-based conjugate fiber having a second component is disclosed.
When E is used, the melting point difference between the sheath and the core is so small that it is not suitable for through-air processing or the like. In order to obtain a difference in melting point between the first component and the second component, a relatively low-density linear low-density polyethylene resin, very low density, is used for the second component.
y polyethylene (VLDPE) and u
ltra low density polyethy
When "lene" (ULDPE) is used, the resin density is reduced to cause stickiness on the fiber surface, resulting in a reduction in workability such as NEP during card processing, and a decrease in bulk and adhesive strength when used as a through-air nonwoven fabric. Disadvantage occurs.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks of the prior art, to reduce the card workability, to be suitably used for the pressure bonding method and the through-air bonding method, and to be flexible. It is an object of the present invention to provide a polyethylene-based conjugate fiber capable of obtaining a nonwoven fabric having a texture and exhibiting high strength, and a nonwoven fabric using the same.

[0006]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems of the conventional polyethylene fibers, and as a result, have found that the first component consisting of a polyethylene resin having a density of 0.940 g / cm ³ or more has The present inventors have found that a polyethylene-based composite fiber comprising a second component containing a polyethylene resin having a Q value of 3.0 or less polymerized by a metallocene catalyst can achieve the intended purpose, and have completed the present invention. The present invention has the following configuration.

(1) A sheath-core composite fiber made of a polyethylene resin, wherein the first component (core component) has a density of 0.94.
It consists 0 g / cm ³ or more polyethylene resins, characterized in that it comprises a second component Q value (sheath component) is polymerized with a metallocene catalyst (weight average molecular weight Mw / number average molecular weight Mn) 3.0 The following polyethylene resin Polyethylene composite fiber. (2) The first component has a density of 0.945 to 0.965 g / c.
The polyethylene-based conjugate fiber according to the above (1), which is a high-density polyethylene having a m ³ and a melting point of 125 to 135 ° C. (3) The first component has a melt flow rate of 5 to 45 g / 10 min.
(1) The polyethylene-based composite fiber according to the above (1) or (2), which is a high-density polyethylene having a temperature (190 ° C., 2160 g, method B). (4) Density 0.850 to 0.930 g of the polyethylene resin contained in the second component polymerized by the metallocene catalyst
The polyethylene-based composite fiber according to the above (1), which is a polyethylene resin having a Q / cm ³ and a Q value of 2.5 or less. (5) A melt flow rate of 5-45 in which the polyethylene resin contained in the second component is polymerized by a metallocene catalyst.
The polyethylene-based composite fiber according to any one of the above (1) to (4), which is a polyethylene having a g / 10 min (190 ° C., 2160 g, method B). (6) The polyethylene composite fiber according to any one of the above (1), (4) and (5), wherein a difference in melting point between the first component and the second component is 5 ° C. or more. (7) A nonwoven fabric using the polyethylene-based composite fiber according to any one of the above (1) to (6). (8) The nonwoven fabric according to the above (7), wherein the fibers are thermally fused to each other by through-air processing. (9) The nonwoven fabric according to the above (7), wherein the fibers are point-bonded to each other by point bonding. (10) A nonwoven fabric obtained by mixing the polyethylene-based conjugate fiber according to any one of the above items (1) to (6) with a fiber that is substantially non-adhesive at a temperature at which the fiber is thermally bonded. (11) The above (7) to (1) wherein the fibers are hydroentangled with each other.
The nonwoven fabric according to any one of the above items 0). (12) The above (7) to-obtained by the spun bond method
(9) The nonwoven fabric according to any one of the above (9). (13) The nonwoven fabric according to any one of the above (7) to (12), wherein the web shrinkage at 120 ° C. processing is 15% or less. (14) A medical article using the nonwoven fabric according to any one of the above (7) to (13). (15) An article for a sanitary material using the nonwoven fabric according to any one of the above (7) to (13). Hereinafter, the present invention will be described in detail.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The polyethylene resin as the first component in the present invention refers to a polymer of ethylene alone or a maximum of 2% by weight of ethylene alone polymerized by a low pressure method using a known Ziegler-Natta catalyst. % Of C ₃ -C
_A copolymer containing ₁₂ alkenes as a comonomer,
Generally 0.940 to 0.965 g / cm ^3, preferably 0.9
A density of 45-0.960 g / cm ³ , and 125-13
It has a melting point of 5 ° C. and a melt flow rate (MF) of 5 to 45 g / 10 min, preferably 20 to 40 g / 10 min.
R: JIS K7210 (190 ° C., 2160 g, B
Value). Hereinafter, the melt flow rate in the present invention refers to a value measured under these conditions. )
Is a high-density polyethylene resin having

The polyethylene resin of the second component as used in the present invention is a polymer which has been polymerized using a metallocene catalyst and has substantially no long branched chain, and usually has a proportion of C ₃ -C of not more than 15% by weight.
_12- alkene as a comonomer and generally ranges from 0.850 to 0.930 g / cm ³
And a melting point of less than 125 ° C., a Q value of 3.0 or less, and 5 to 45 g / 10 min, preferably 25 to 40 g.
It is a linear low-density polyethylene resin having a melt flow rate of / 10 min. (Hereinafter, this polyethylene resin will be referred to as a metallocene polyethylene resin.) When the density of the metallocene polyethylene resin used as the second component is less than 0.850 g / cm ³ , the fibers become sticky and the card processability increases. Causes a drop in Further, when a resin exceeding 0.930 g / cm ³ is used, the melting point of the resin becomes high, and the melting point difference between the first component and the second component cannot be obtained. Although the strength of the obtained nonwoven fabric is high, there is a problem that the feeling is reduced. From this, the suitable density of the metallocene polyethylene resin used for the second component is 0.850 to 0.930 g / cm ³ , preferably 0.9.
The range is from 0.000 to 0.925 g / cm ³ . A preferred value for the Q value is 3.0 or less, more preferably 2.5 or less. When the Q value exceeds 3.0, the proportion of the low molecular weight component in the resin component increases, so that the resulting fiber has increased tackiness and reduced adhesive strength.

The metallocene polyethylene resin within the above range can be easily obtained by using a metallocene catalyst. A typical compound as such a metallocene catalyst is bis (cyclopentadienyl) zirconium dichloride,
Bis (cyclopentadienyl) hafnium dichloride, ethylenebis (indenyl) zirconium dichloride, ethylenebis (indenyl) hafnium dichloride, isopropylidene (cyclopentadienyl-9-
Fluorenyl) zirconium dichloride, isopropylidene (cyclopentadienyl-9-fluorenyl) hafnium dichloride, isopropylidene (cyclopentadienyl-2,7-dimethyl-9-fluorenyl) zirconium dichloride, isopropylidene (cyclopentadienyl-2) , 7-dimethyl-9-fluorenyl)
Hafnium dichloride, dimethylsilanediylbis (2,4,5-trimethylcyclopentadienyl) zirconium dichloride, dimethylsilanediylbis (2,4-dimethylcyclopentadienyl) zirconium dichloride, dimethylsilanediylbis (2,4
5-trimethylcyclopentadienyl) hafnium dichloride and dimethylsilanediylbis (2,4-dimethylcyclopentadienyl) hafnium dichloride. Many metallocene polyethylene resins produced using these catalysts are commercially available, and among them, the density, melting point,
It is also possible to appropriately select and use a polyethylene resin having a Q value and a melt flow rate.

When comparing a metallocene polyethylene resin with a polyethylene resin polymerized using a Ziegler-Natta catalyst, it is found that the metallocene polyethylene resin has a lower melting point and a less sticky component even if the density is almost the same. There are features. In addition, due to the feature that the molecular weight distribution is narrow, the spinnability is stable, and the nonwoven fabric using the obtained fiber is flexible and has a good feel, and the adhesive strength and the heat seal strength are improved. In addition to the metallocene polyethylene resin, the second component may be any of LDPE, L-LDPE, VLDPE, ULDP as long as the above characteristics are not impaired.
E and HDPE may be blended and used.

[0012] The polyethylene-based composite fiber constituted by the present invention can be produced by a known melt spinning method and a spunbond method. In addition, composite fibers such as a sheath-core type and an eccentric sheath-core type can be used. When producing a composite fiber, the composite ratio of the first component and the second component is 80/20 to 2 by weight.
The range of 0/80 is preferable, and 50/5 is more preferable.
0 to 70/30. When the high-density polyethylene resin of the first component to be the core component is less than the above range, the rigidity of the fiber tends to decrease, so that the card permeability decreases or the bulk decreases when the nonwoven fabric is used. Care must be taken not to impair the performance. Conversely, when the first component is increased and the second component is decreased from the above range, care must be taken since the adhesive strength of the obtained nonwoven fabric tends to decrease. Therefore, the sheath-core ratio is most preferably in the above range. The difference between the melting points of the first component and the second component constituting the polyethylene fiber of the present invention is preferably 5 ° C. or more, more preferably 15 ° C. or more. The larger the melting point difference, the wider the processing temperature range when processing the nonwoven fabric, and the easier the nonwoven fabric production. The melting point difference referred to in the present invention refers to a temperature difference between a peak on a high melting point side and a peak on a low melting point side observed in a DSC curve obtained by analyzing a fiber with a differential scanning calorimeter (DSC). In addition to the large melting point difference, it is preferable that the melting point of the second component appears as a sharp peak in the differential scanning calorimetry, and the use of a metallocene polyethylene resin having a small Q value for the second component is important in this respect. Also greatly contributes. The polyethylene resin used as a raw material of either or both of the first component and the second component used in the fiber of the present invention does not impair the object of the present invention by using conventionally known antioxidants, light-proofing agents, flame retardants, pigments, and the like. It can be contained in a range.

As the method for stretching the polyethylene-based conjugate fiber constituted by the present invention, known hot roll stretching, hot water stretching and the like can be used, and a one-stage stretching system, a two-stage stretching system, or a multi-stage stretching system is used. Can be. In order to obtain a more bulky nonwoven fabric having good card passing property, it is effective to promote the degree of crystal orientation of the fiber and increase the rigidity of the fiber. As a method of increasing the degree of crystal orientation of the fiber, a method of taking out and orienting the fiber at a high speed during melt spinning of the fiber and a method of drawing at a high draw ratio can be considered. When using the latter method, it is preferable to stretch at a draw ratio of at least 5 to 8 times or more, and more preferably a polyethylene-based composite fiber having rigidity by stretching at a high draw ratio of 10 times or more. can get. Further, the crimp holding force of the fiber is also important, and when mechanical crimping is performed using a known stuffer box, the fiber crimp holding force can be increased by sufficiently applying heat to the fiber just before entering the stuffer box. improves.

The polyethylene-based conjugate fiber of the present invention has other fibers which are substantially non-heat-adhesive at the temperature at which the fiber is heat-bonded, such as polypropylene fiber, polyester fiber, polyamide fiber, polyacrylic vinylon and the like. Regenerated fibers such as synthetic fibers, rayon, cupra, acetate, cotton, wool, silk, hemp, and pulp fibers, and animal fibers can be mixed or mixed within a range that does not impair the effects of the present invention.

The polyethylene composite fiber of the present invention can be suitably used as a raw material for a nonwoven fabric. For example, the nonwoven fabric can be formed into a nonwoven fabric by a known point bond method (also referred to as an embossing method), a through air method, a needle punch method, a hydroentanglement method, and the like. Because of the difference, the processing temperature range for forming the nonwoven fabric can be widened, and the nonwoven fabric can be suitably used for the heat bonding method using the point bonding method and the through air method. When a nonwoven fabric is obtained by a through-air method, if the heat shrinkage of the fiber is large, the fiber shrinks due to heat during processing, and the resulting nonwoven fabric has problems such as poor dimensional stability, poor formation, and tightness. Has a web shrinkage of 15% or less,
It is necessary to suppress it to preferably 10% or less (120 ° C. oven heating). In order to suppress web shrinkage, it is necessary to increase the fluidity of the resin melted from the nozzle. Examples of the method include raising the melting temperature during spinning, or using a resin having a relatively high melt index. When the polyethylene resin is melted at a high temperature, a gel (thermally crosslinked deterioration product) is generated, which causes a yarn breakage during spinning. Therefore, the latter is a more effective means for suppressing web shrinkage. Since the polyethylene-based composite fiber of the present invention is not particularly deteriorated by radiation irradiation, the obtained non-woven fabric is used for medical applications such as radiation-irradiated clothing, surgical caps, sheets, surgical clothing, surgical gowns, and medical examination clothing. Can be widely used as. Further, the nonwoven fabric of the present invention,
As an absorbent article, it can be preferably used especially as a disposable diaper for infants and adults, a napkin, etc., and also as an article for a sanitary material such as a sweat absorbing pad, a sebum removing sheet material, a hand wipe, a toilet wipe, and a wiper.

[0016]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. The conditions for producing raw cotton, the methods for evaluating the properties of the examples and the comparative examples, and the measured values in the present invention are as shown below.

The raw cotton production conditions used in the present invention include:
In the combination of the first component and the second component polyethylene resin shown in Table 1, the first component was 240 ° C., and the second component was 200 ° C.
At ℃, it was extruded from a spinneret having a hole diameter of 0.8 mmφ and was taken out at a spinning speed of 376 m / min to obtain a polyethylene composite fiber having 18.7 dtex. After stretching this unstretched yarn at a draw ratio of 10 using a hot water stretching device filled with warm water at 90 ° C., applying a zigzag crimp with a push-in crimper and drying it with a hot air suction dryer at 80 ° C. ,
It was cut to a length of 51 mm. The fineness of the obtained fiber is 2.2
dtex.

The web was produced using a high-speed sample roller card manufactured by Daiwa Kiko Co., Ltd. to produce a web having a basis weight of 20 g / m ² . At this time, the occurrence state and formation of the neps were observed, and the judgment was made based on the following evaluation. …: A uniform web was obtained without nep. Δ: A small amount of NEP was observed, but a uniform web was obtained. X: A large amount of neps were generated and a uniform web could not be obtained.

The web having a basis weight of 20 g / m ² obtained above was subjected to through-air processing and embossing to obtain a nonwoven fabric. The nonwoven fabric processing conditions are shown below. Through-air processing: Using a hot-air circulation type suction band dryer, heat fusion was performed at an air speed of 0.8 m / s and a processing speed of 8.5 m / min. Processing temperature is 110, 11
5, 120 and 125 ° C. Embossing: Thermocompression bonding was performed at a linear pressure of 1.96 Mpa and a processing speed of 6.0 m / min using a pair of upper and lower embossing rolls having an embossing area ratio of 25% and a flat roll. Processing temperature is 105, 110, 11
5, and 120 ° C.

The strength of the nonwoven fabric was measured by measuring the obtained through-air nonwoven fabric and embossed nonwoven fabric in a size of 15 cm × 5 cm (MD × C
D: MD strength measurement sample), 5 cm × 15 cm (MD
× CD: CD strength measurement sample), and using an Autograph AG-500D manufactured by Shimadzu Corporation at a tensile speed of 20
The breaking strength of the sample was determined at 0 m / min.

For the measurement of web shrinkage, a high-speed sample roller card was used to make a web by passing 100 g of raw cotton. This web was cut into 25 × 25 cm, cut out in the MD direction, and 1 cm center (up and down) from the center and sides of the sample were measured at a total of three places. next,
The cut sample was placed in an oven heated to 120 ° C. for 5 minutes and heat-treated. After standing at room temperature for 5 minutes, the place measured before the heat treatment was measured again.
The web shrinkage was determined using the following formula. (Formula) Web shrinkage = (A−B) × 100 / A
(%)

The texture of the nonwoven fabric was evaluated by 10 panelists. As a result, 9 or more felt soft, ◎ when 5 or more felt soft, and soft. The case where the number of people was 4 or less was evaluated as △, the case where the number of people who felt flexibility was 2 or less was evaluated as X, ◎ and と し た were determined to be within the practical range, and Δ and × were determined outside the practical range. Further, the case where shrinkage such as twitching was observed in the nonwoven fabric obtained in the nonwoven fabric processing (through air and embossing) was also out of the practical range.

In Examples 1, 3, and 4, the density of the metallocene polyethylene resin used for the second component was changed within the present invention. Both have good card passing properties,
Web shrinkage was also less than 10%.

Example 2 uses a high MFR resin for both the first and second components. The card passability is good and the web shrinkage is reduced.

Example 5 has the same resin composition as in Example 2, except that the ratio of the first component to the second component is changed from 70/30 to 50/50. The card passability was good, and the web shrinkage was 10% or less.

In Example 6, the metallocene polyethylene resin used for the sheath is blended with a Ziegler-Natta polyethylene resin at 40%. The card passing property was good, and the web shrinkage was 10% or less.

Comparative Example 1 is a resin having the same density and MFR as in Example 1 made of Ziegler-Natta polyethylene resin, and Comparative Examples 2, 3, and 4 increase the density of the second component. In Comparative Example 1, the card passing property was very poor, and a large amount of NEP occurred, so that a web sample could not be collected. In Comparative Examples 2, 3, and 4, the higher the density, the higher the cardability, but the higher the web shrinkage.

Comparative Example 5 is based on a combination of a Ziegler-Natta polyethylene resin having a high MFR. A small amount of NEP is seen in the carding process, and the web shrinkage is 1
It was as high as 5% or more.

In Comparative Example 6, the ratio of the first component to the second component in Comparative Example 2 was changed from 70/30 to 50/50. However, since the card passing property was poor and a large amount of NEP was generated, Web samples were not available.

The fibers of Examples 1, 2, 3, 4, 5, and 6 were processed by through-air nonwoven fabric, and the physical properties of the nonwoven fabric were measured. The results of Examples 7, 8, 9, 10, 11, and 12 in Table 2 are shown in Table 2. is there. In any case, since the processing temperature width is large, nonwoven fabric processing is easy, and low-temperature processability is improved. In addition, it was found that the nonwoven fabric was flexible and had a good feel, and had a high specific volume and high strength.

The fibers of Comparative Examples 2, 3, and 5 were processed through-air nonwoven fabrics, and the physical properties of the nonwoven fabrics were measured. The results are Comparative Examples 7, 8, and 10 in Table 2. In any case, since the processing temperature range is narrow, it is difficult to process the nonwoven fabric, and the low-temperature processability is reduced. Further, the specific volume is low, and the nonwoven fabric is hard and impairs the feeling. Compared with the through-air nonwoven fabric using the fiber obtained in the present invention, the strength at each processing temperature is low, and the difference in strength at the time of low-temperature processing is the largest.

An attempt was made to produce a nonwoven fabric by subjecting the fiber of Comparative Example 4 to through-air processing. However, the surface was tight and the formation was extremely poor. As shown in Comparative Example 9 in Table 2, the physical property data were obtained. No nonwoven fabric that could be measured was obtained.
This is because the difference in melting point between the first component and the second component is extremely narrow.

The fibers of Examples 1, 2, 3, 4, 5, and 6 were processed into an embossed nonwoven fabric, and the physical properties of the nonwoven fabric were measured. The results of Examples 13, 14, 15, 16, 17, and 18 in Table 3 are shown.
It is. In any case, the nonwoven fabric processing is easy because the processing temperature width can be taken, and the low-temperature workability is improved. Further, the obtained nonwoven fabric had high strength, was very soft and had a good feel.

The fibers of Comparative Examples 2, 3, 4, and 5 were processed into an embossed nonwoven fabric, and the physical properties of the nonwoven fabric were measured. The results of Comparative Examples 11, 12, 13, and 14 in Table 3 are shown in Table 3. In any case, the non-woven fabric processing is difficult because the processing temperature width is narrow, and the low-temperature workability is reduced. Moreover, the obtained nonwoven fabric was hard and the hand was reduced. Compared with the embossed nonwoven fabric using the fiber obtained in the present invention, the strength at each processing temperature is low, and the difference in strength at the time of low-temperature processing is the largest.

The through-air nonwoven fabric using the fiber obtained in the present invention was cut off from the surface material of a commercially available disposable diaper for adults, and the nonwoven fabrics of Example 7 and Comparative Example 7 in Table 2 were fixed. When the wearing test of Comparative Example 15 was carried out, the adult disposable diaper of Example 19 had a very good feel and had the strength to withstand use, and the adult disposable diaper of Comparative Example 15 had a sticky feeling, and thus had a soft touch. It was confirmed that it was bad and the wearing feeling was bad.

[0036]

[Table 1]

[0037]

[Table 2]

[0038]

[Table 3]

[0039]

The polyethylene-based conjugate fiber of the present invention has a sufficient melting point difference between the first component and the second component, so that nonwoven fabric processing is easy and low-temperature processability is improved. Also,
The obtained non-woven fabric is bulky and flexible, and shows higher adhesive strength. In particular, it can be suitably used as through-air raw cotton, which has been conventionally difficult to use, and has performance suitable not only for medical use but also for sanitary use.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) D04H 1/54 D04H 3/14 A 3/00 3/16 3/14 A61F 13/18 310Z 3/16 F Terms (reference) 4C003 AA16 4C081 AA01 BB04 BB07 BB08 BC03 CA021 DA05 4L041 AA07 AA20 BA02 BA05 BA21 BA49 BD03 BD07 BD11 CA36 CA37 CA62 DD01 DD04 DD05 DD18 4L047 AA14 AA27 AB03 AB10 BA09 BA23 BB01 CC03 EA

Claims (15)

[Claims] 1. A sheath-core composite fiber comprising a polyethylene resin, wherein the first component (core component) has a density of 0.940 g / core.
It consists cm ³ or more polyethylene resin, characterized in that it comprises a second component Q value (sheath component) is polymerized with a metallocene catalyst (weight average molecular weight Mw / number average molecular weight Mn) 3.0 The following polyethylene resin Polyethylene composite fiber. 2. The composition according to claim 1, wherein the first component has a density of 0.945 to 0.965 g /.
cm ^3, a polyethylene-based composite fiber according to claim 1 which is a high density polyethylene having a melting point of 125-135 ° C.. 3. The method according to claim 1, wherein the first component has a melt flow rate of 5 to 45 g /.
The polyethylene-based composite fiber according to claim 1 or 2, which is a high-density polyethylene having 10 minutes (190 ° C, 2160 g, method B). 4. The polyethylene resin contained in the second component,
Density 0.850-0.9 polymerized by metallocene catalyst
30 g / cm ^3, a polyethylene-based composite fiber according to claim 1 is a Q value of 2.5 or less polyethylene resin. 5. The polyethylene resin contained in the second component,
Melt flow rate 5 polymerized by metallocene catalyst
The polyethylene-based composite fiber according to any one of claims 1 to 4, wherein the polyethylene-based composite fiber is polyethylene having a weight of 45 g / 10 min (190 ° C, 2160 g, method B). 6. The polyethylene-based composite fiber according to claim 1, wherein a difference in melting point between the first component and the second component is 5 ° C. or more. 7. A nonwoven fabric using the polyethylene-based composite fiber according to any one of claims 1 to 6. 8. The nonwoven fabric according to claim 7, wherein the fibers are thermally fused by through-air processing. 9. The nonwoven fabric according to claim 7, wherein the fibers are point-bonded to each other by a point bonding process. 10. A nonwoven fabric obtained by mixing the polyethylene-based composite fiber according to any one of claims 1 to 6 and a fiber which is substantially non-adhesive at a temperature at which the fiber is thermally bonded. 11. A fiber according to claim 7, wherein the fibers are hydroentangled.
0 The nonwoven fabric according to any one of 0. 12. The method according to claim 7, which is obtained by a spunbond method.
10. The nonwoven fabric according to any one of claims 9 to 9. 13. A web shrinkage ratio at processing at 120 ° C. of 1
The nonwoven fabric according to any one of claims 7 to 12, which is 5% or less. 14. A medical article using the nonwoven fabric according to any one of claims 7 to 13. 15. An article for a sanitary material using the nonwoven fabric according to any one of claims 7 to 13.