JP2000054251A - Nonwoven fabric and absorbing article using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermo-compressive nonwoven fabric having good feeling, free from the generation of an edge when bent and having high nonwoven fabric strength or the like, and a liquid-absorbing article or the like such as a paper diaper using the nonwoven fabric. SOLUTION: This nonwoven fabric consists mainly of a thermally adhesive fiber. The nonwoven fabric is prepared by thermally compressing the fiber into a nonwoven fabric, subsequently subjecting the obtained nonwoven fabric to drawing to obtain a thermo-compressive nonwoven fabric having a stress F1 (F1 is the stress in terms of the width of 5 cm and unit area weight of 1 g/m2) at 3% elongation in the machine direction of less than 25 gf and a stress F2 (F2 is the stress in terms of the width of 5 cm) at 5% elongation of 500 gf or more. An absorbing article is prepared by using the thermo- compressive nonwoven fabric.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nonwoven fabric and an absorbent article using the same. More specifically, the present invention relates to a thermocompression-bonded nonwoven fabric which has a soft texture, does not generate a bend angle, and has excellent strength and the like, and a liquid absorbent article using the same.

[0002]

2. Description of the Related Art Thermocompression-bonded non-woven fabrics made of heat-adhesive fibers as raw materials have moderate flexibility and mechanical strength, and are widely used for disposable diapers and sanitary napkin surface materials, disposable towels, and various wipers. It's being used. Since this nonwoven fabric is frequently used for applications in the field of directly touching human skin, a better texture is required. In particular, for disposable diapers and the like used for newborn babies, there has been a demand for a nonwoven fabric which is flexible and does not cause any breakage of the nonwoven fabric and does not cause rough skin due to the breakage angle.

[0003] Japanese Patent Application Laid-Open No. 8-49166 discloses a thermocompression-bonded nonwoven fabric using an embossing roll using a low-oriented polypropylene fiber to which a specific oil agent is attached. Also,
Japanese Patent Application Laid-Open No. 62-263321 discloses a thermocompression-bonded nonwoven fabric by embossing rolls using a polyolefin-based heat-fusible fiber to which a specific amount of a petroleum resin is added. The nonwoven fabric disclosed in the above technology is a nonwoven fabric having a high strength and a satisfactory texture to some extent. However, thermocompression bonding nonwoven fabrics and the like using an embossing roll or the like are likely to be heat-sealed at locations other than the embossed portion, and since the fibers are excessively entangled at the time of manufacturing the web, they tend to have high rigidity.
Japanese Patent Application Laid-Open No. 60-162851 discloses that a nonwoven fabric partially bonded to a pair of a metal roll having a projection and an elastic roll is passed through, and the surface thereof is rubbed with the metal roll having the projection to form a nonwoven fabric. Are disclosed.
However, although the flexibility is improved by this method, there is a problem in that the mechanical strength is reduced or the hair is fluffed because the thermocompression bonding point is broken. Further, when the nonwoven fabric is used as a surface material such as a disposable diaper, there is a problem that the hair is removed and adheres to the skin. Further, there is a problem that the elastic roll is easily damaged by the projection of the metal roll, and it is impossible to increase the production speed. In particular, in the case of a thin nonwoven fabric, it has been difficult to produce a uniform nonwoven fabric that is free of breakage and fluff. The air-through fused nonwoven fabric of the heat-adhesive conjugate fiber is
Although the texture is relatively good, there is a problem that corners are easily generated when the nonwoven fabric is bent.

[0004]

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and is a thermocompression bonding method which has a good texture, does not have a bend angle, and has excellent nonwoven fabric strength. An object of the present invention is to provide a nonwoven fabric and a liquid absorbent article using the same.

[0005]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems, and as a result, have found that it can be solved by adopting the following configuration, and have completed the present invention.

[0006] 1. A non-woven fabric mainly composed of thermo-adhesive fibers, which is thermocompressed to form a non-woven fabric, and then the non-woven fabric is subjected to a stretching treatment so that the non-woven fabric has a 3%
The stress F1 at the time of elongation (F1 is a width of 5 cm and a stress converted to a basis weight of 1 g / m ² ) is less than 25 gf, and the stress F2 at an elongation of 5% (F2 is a stress per 5 cm of width) is A thermocompression-bonded nonwoven fabric of 500 gf or more. 2. Thermo-compression non-woven fabric, machine direction length 15cm, width 5c
2. The thermocompression-bonded nonwoven fabric according to claim 1, wherein a mangled non-woven fabric test piece is formed, and when the test piece is curved to form a loop, no bend angle occurs. 3. 3. The thermocompression-bonded nonwoven fabric according to the above item 1 or 2, wherein the stretch ratio of the nonwoven fabric is 1.05 to 1.40. 4. 4. The thermocompression-bonded nonwoven fabric according to any one of the above items 1 to 3, wherein the thermoadhesive fibers are monocomponent fibers. 5. The above-mentioned item 1, wherein the heat-adhesive fiber is a spunbond filament.
5. The thermocompression-bonded nonwoven fabric according to any one of items 4 to 4. 6. Item 6. The thermocompression-bonded nonwoven fabric according to any one of Items 1 to 5, wherein the heat-adhesive fibers are polyolefin-based monocomponent fibers. 7. 7. The thermocompression-bonded nonwoven fabric according to any one of the above items 1 to 6, wherein the thermoadhesive fibers are polypropylene monocomponent fibers. 8. 6. The thermocompression-bonded nonwoven fabric according to any one of the above items 1, 2, 3 and 5, wherein the thermoadhesive fibers are conjugate fibers. 9. 9. The conjugate fiber according to item 8, wherein the conjugate fiber is composed of a low-melting thermoplastic resin having a melting point difference of 15 ° C. or more and a high-melting thermoplastic resin, and wherein the low-melting thermoplastic resin forms at least a part of the fiber surface. 2. The thermocompression bonding nonwoven fabric according to 1. 10. 9. The thermocompression-bonded nonwoven fabric according to the item 8, wherein the conjugate fiber is a sheath-core or side-by-side thermoadhesive conjugate fiber composed of a low-melting-point polyolefin-based resin and a high-melting-point polyolefin-based resin. 11. 9. The thermocompression-bonded nonwoven fabric according to the above item 8, wherein the conjugate fiber is a sheath-core or side-by-side thermoadhesive conjugate fiber composed of a polyolefin-based resin and a polyester-based resin. 12. 9. The thermocompression-bonded nonwoven fabric according to the above item 8, wherein the conjugate fiber is a sheath-core or side-by-side thermoadhesive conjugate fiber composed of a low-melting polyester resin and a high-melting polyester resin. 13. An absorbent article using the thermocompression-bonded nonwoven fabric according to any one of the above items 1 to 12.

Hereinafter, the present invention will be described in detail. The present invention relates to a nonwoven fabric obtained by thermocompression bonding a fiber assembly mainly composed of heat-fusible fibers, and an absorbent article using the nonwoven fabric. The thermocompression-bonded nonwoven fabric referred to in the present invention is a nonwoven fabric thermocompression-bonded mainly between an embossing roll and a flat roll engraved in a dot shape. The thermo-adhesive fibers serving as the main fibers of the nonwoven fabric are monocomponent fibers or composite fibers using a thermoplastic resin such as a polyolefin resin, a polyester resin, or a polyamide resin as a raw material. From the viewpoints of workability, cost, and the like of the nonwoven fabric, those obtained by fibrillating a polyolefin-based resin or a polyester-based resin are preferably used. As a thermoplastic resin, polypropylene, high-density polyethylene, low-density polyethylene, linear low-density polyethylene, ethylene-propylene copolymer, ethylene-butene-1 copolymer,
Ethylene-propylene-butene-1 copolymer, ethylene-
Polyolefin resins such as vinyl acetate copolymer, polyamide resins such as nylon 6, nylon 66, polyester resins such as polyethylene terephthalate, polybutylene terephthalate, polyethylene terephthalate isophthalate copolymer, polyphenylene sulfide, polyvinylidene fluoride, etc. Can be used.

In the case where the heat-fusible fiber is a monocomponent fiber, a fiberized material obtained by melt-spinning the thermoplastic resin alone or two or more uniformly mixed resins can be used. Such fibers are also called regular fibers. In the case of a composite fiber, a composite fiber obtained by composite spinning of the thermoplastic resin can be used. In the case of a monocomponent fiber, polyethylene fiber, propylene / ethylene copolymer fiber, propylene / ethylene / butene-1 copolymer fiber, polypropylene fiber, polyethylene terephthalate fiber and the like can be preferably used. In the case of composite fibers, side-by-side,
Any of composite fibers such as sheath-core type, eccentric sheath-core type, sea-island type, and polydisperse type can be used. Particularly, a heat-fusible conjugate fiber having a melting point difference of 15 ° C. or more and a low-melting thermoplastic resin forming at least a part of the fiber surface can be preferably used.
For example, low density polyethylene / polypropylene, linear low density polyethylene / polypropylene, propylene / ethylene copolymer / polypropylene, propylene / ethylene / propylene
Butene-1 copolymer / polypropylene, linear low density polyethylene / polyethylene terephthalate, propylene
Ethylene copolymer / polyethylene terephthalate, poly (ethylene terephthalate-co-isophthalate) /
Examples thereof include composite fibers of a combination of polyethylene terephthalate and the like. In the case of composite fibers, the composite ratio of the low melting point thermoplastic resin and the high melting point thermoplastic resin is 10
90% by weight, 90 to 10% by weight of high melting point resin, preferably 20 to 80% by weight of low melting point resin, more preferably 30 to 70% by weight of low melting point resin and 70 to 30% by weight of high melting point resin. . When the low melting point resin of the conjugate fiber is less than 10% by weight, or when the high melting point resin exceeds 90% by weight, the texture is improved based on the physical properties peculiar to the low melting point resin, and the processing temperature range at the time of point bond thermocompression bonding is reduced. The effect of wide setting can be reduced. In particular, heat-fusible conjugate fibers composed of a combination of a low-melting-point polyolefin-based resin / high-melting-point polyolefin-based resin, a polyolefin-based resin / polyethylene terephthalate-based resin, and the like can be preferably used.

The thermoadhesive fibers used in the thermocompression-bonded nonwoven fabric of the present invention may be any of staple fibers having a fiber length of about 3 mm to 130 mm, and long fibers having a substantially endless fiber length. The fibers may or may not be crimped. When there is a crimp, any of a substantially zigzag shape, a substantially U shape, a substantially ohmic shape, a substantially spiral shape and the like and a mixture of crimps thereof can be used. The number of crimps is about 0.3 to 65 mountains / 25
mm. Also, the single fiber fineness of the fiber is at least 0.2 d.
/ F, and the upper limit is not particularly limited. However, when the nonwoven fabric is used for surface materials such as disposable diapers, the single-fiber fineness is about 0.2 to 12 d /
f, especially 0.5 to 8 d / f.

[0010] The thermocompression-bonded nonwoven fabric of the present invention is a nonwoven fabric mainly containing the above-mentioned thermoadhesive fibers. That is, the main meaning means that the nonwoven fabric contains at least 51% by weight of the heat-adhesive fiber. Also, as long as the object of the present invention can be achieved, other fibers such as rayon, cotton, acrylic fiber, silk, carbon fiber and the like may be mixed with the heat-adhesive fiber in an amount of less than 49% by weight. When other fibers are mixed for the purpose of hydrophilicity, etc., other fibers such as cotton are about 5 to 30% by weight.
The effect can be demonstrated with. For the purpose of softness such as silky feeling, the effect can be obtained by mixing about 0.5 to 15% by weight of silk or irregularly shaped yarn.

The thermocompression-bonded nonwoven fabric of the present invention is obtained by forming a web by a card method, an air laid method, a wet papermaking method, or the like, by mixing 100% by weight of the thermoadhesive fibers or the thermoadhesive fibers with other fibers. Subsequently, it is obtained by performing thermocompression bonding to form a nonwoven fabric and further performing a stretching process described later. Also, the thermoplastic resin is processed by a melt blow method, a normal spunbond method or a composite spunbond method to form a web of heat-fusible fibers, and then thermocompression-bonded to form a nonwoven fabric, which is then subjected to a stretching process described later. Can be Of course, a nonwoven fabric combining these may be used. Among them, a nonwoven fabric formed by a card method, a spun bond method, or a combination thereof is preferable for achieving the effects of the present invention. For the thermocompression bonding, a thermocompression bonding device including a metal embossing roll and a metal flat roll, an ultrasonic point bonding device, and the like can be used. In particular, a thermocompression bonding device including a metal embossing roll and a metal flat roll can be preferably used. Using the thermocompression bonding apparatus, the web is subjected to heating, compression bonding, and the like under conditions at or above the temperature at which the web is thermocompressed to form a nonwoven fabric. The thermocompression conditions such as thermocompression temperature and linear pressure are determined by the web used and the processing speed. In short, it is sufficient that the thermocompression bonding is sufficiently performed so that the thermocompression bonding portion is not destroyed in the next stretching step. The area of the convex portion of the embossing roll, that is, the thermocompression bonding area of the thermocompression bonding nonwoven fabric is preferably about 5 to 35%. Thermocompression bonding area is 5
%, The strength of the nonwoven fabric may be reduced or fluff may be generated. On the other hand, if the thermocompression bonding area exceeds 35%, it may be difficult to improve the flexibility of the nonwoven fabric and the bending angle. The convex shape of the embossing roll is circular, diamond, oval,
Various shapes such as a square, a rectangle, a bar, and a cross are possible. Further, a material having a distance between the embossed protrusions of about 0.5 to 5.0 mm is suitable. Further, the nonwoven fabric of the present invention may be a nonwoven fabric thermocompressed with a metal flat roll / metal flat roll. Further, the nonwoven fabric of the present invention may be a material in which air-through heat fusion and emboss roll thermocompression bonding are used in combination.

The thermocompression-bonded nonwoven fabric is stretched, and the stress characteristics of the nonwoven fabric in the low elongation region are set to the values of the present invention. The nonwoven fabric of the present invention has a stress (F1) at 3% elongation in the machine direction of less than 25 gf and a stress (F2) at 5% elongation of 500 gf or more. Where F1 is 5c in width
m, the stress when converted per unit weight of 1 g / m ² ,
Is the stress per 5 cm width without conversion to basis weight. F1
If it is 25 gf or more, the texture of the nonwoven fabric such as flexibility is inferior.
Further, when F2 is less than 500 gf, when this nonwoven fabric is laminated with another sheet or a liquid absorbing material and processed at a high speed into an intermediate product or a final product, the nonwoven fabric is excessively stretched or wrinkles are generated in the nonwoven fabric. , The workability is inferior and the performance of the final product is inferior.

The stretching of the nonwoven fabric may be performed by stretching the thermocompressed nonwoven fabric using a stretching machine at a stretching ratio of about 1.05 times or more and a stretching rate of not breaking the nonwoven fabric. For example, in the case of a nonwoven fabric having a breaking elongation of about 55%, the stretching ratio is about 1.05.
With a factor of up to 1.40, the nonwoven fabric stress in the low elongation region of the nonwoven fabric can be set within the above numerical range. When the nonwoven fabric elongation after thermocompression bonding is relatively large, the stretching treatment can be performed at a relatively high magnification. The draw ratio is preferably about 1.08
It is about 1.30 times. If the stretching ratio is less than 1.05 times,
It is difficult to set the flexibility of the nonwoven fabric and the stress (F1) at 3% elongation to the above-mentioned numerical values. The stretching ratio is 1.40.
If the ratio is twice or more, the nonwoven fabric may be broken, and even if the nonwoven fabric is not broken, the strength of the nonwoven fabric is reduced, and fluff is generated. Also, it is difficult to set the stress (F2) at the time of 5% elongation to the above value. The drawing of the nonwoven fabric is performed at a temperature lower than the melting point or softening point of the thermoadhesive fiber. If the stretching temperature is too high, the nonwoven fabric becomes undesirably hard. The nonwoven fabric can be stretched not only in the machine direction but also in the transverse direction. Further, after the thermo-compression-bonded non-woven fabric is stretched, it can be subjected to relaxation treatment. The relaxation treatment includes a tension absorbing bar, a tension absorbing roll,
It may be processed by an air blow machine or the like. Thermocompression bonding, stretching and the like can be performed by a continuous method in the nonwoven fabric manufacturing process. Also, once the thermocompression-bonded non-woven fabric is manufactured, the non-woven fabric is wound up, and then the non-woven fabric is unwound.

The basis weight of the thermocompression-bonded nonwoven fabric of the present invention is not particularly limited. However, it is preferably 10 to 100 g / m ² , and more preferably 12 to 50 g / m ² , from the viewpoint of improving the texture and the angle of bending of the nonwoven fabric. In particular, for applications such as liquid absorbent articles, the basis weight is 12 to 30 g / m ² . If the basis weight is less than 10 g / m ² , the non-woven fabric stress F2 becomes too low, which is not preferable. If it exceeds 100 g / m ² ,
The thermocompression bonding becomes difficult, and the texture becomes poor.

The absorbent article of the present invention is an article in which the nonwoven fabric is used as a material constituting a liquid absorbent article.
For example, in the case of a disposable diaper, the disposable diaper is formed by laminating the nonwoven fabric with another nonwoven fabric, a tissue, a pulp, a highly water-absorbing material, a film or the like. For example, a polyethylene sheet is used as a liquid leakage-preventing back sheet, a pulp wrapped in a tissue and a liquid absorbing material containing a high water-absorbing agent, and the nonwoven fabric of the present invention is used as a surface material. And a liquid absorbent article such as a disposable diaper integrated with the above. Such a liquid-absorbent article has a soft surface material and cannot be bent, so that diaper rash and the like hardly occur. Further, a polyethylene sheet is laminated on the nonwoven fabric of the present invention so that the nonwoven fabric layer forms the outer side, and a sheet having a laminated structure in which both are at least partially fused and integrated is used as a back sheet, A liquid absorbent article such as a disposable diaper in which the nonwoven fabric of the invention or another nonwoven fabric or another apertured film is used as a surface material, and a back material and a surface material are integrated by thermocompression bonding or the like,
The back material has a good texture. Further, a disposable diaper or the like having a structure such as a surface material / liquid absorbing material / back surface material obtained by laminating the nonwoven fabric of the present invention with another nonwoven fabric, web, or the like can be exemplified. This disposable diaper has a good texture, has an effect of preventing diaper rash, and has an effect of further improving liquid absorbency. In addition, a heat-sealing nonwoven fabric made of rayon and heat-fusible fibers is used as a liquid absorbing material, and hydrophilic fibers such as rayon are 5 to 40% by weight, heat-fusible fibers 95 to
An article having a structure in which the non-woven fabric of the present invention mixed with 60% by weight and thermally fused with the fibers is used as a cover material and wraps the entire liquid absorbing material can be used as a sweat-absorbing material or a makeup remover.

The nonwoven fabric of the present invention is obtained by stretching a partially thermocompressed nonwoven fabric at a specific ratio and setting two types of stress characteristics in a low elongation region to have specific numerical values. is there. The effect of the stretching process is considered as follows. That is, in order to have high mechanical strength in the thermocompression bonding nonwoven fabric, it is necessary to strongly thermocompression bond with an embossing roll or the like. A weak heat seal is produced.
Also, a slight heat shrinkage during the thermocompression treatment causes a phenomenon that the fibers are excessively tensioned between the thermocompression bonding portions. That is, it tends to be a product having a small degree of freedom with respect to the stress between the single fibers between the thermocompression bonding portions. This results in a nonwoven fabric having a hard feel and a poor touch. Therefore, such a non-woven fabric is subjected to appropriate stretching and, if necessary, relaxation treatment, and the two types of stress characteristics in the low elongation region of the non-woven fabric are set as in the present invention. The tension can be released. As a result, the texture such as flexibility is good, the strength of the nonwoven fabric is high, and the suitability for machining can be maintained. Furthermore, in addition to the above-mentioned features, a nonwoven fabric free of a break angle can be provided.

[0017]

The present invention will be described below in detail with reference to examples. However, the present invention is not limited to these examples. Each physical property value in the following Examples and Comparative Examples is based on the following measurement methods.

[F1 and F2] A test piece having a length of 15 cm in the machine direction and a width of 5 cm is cut from the nonwoven fabric. Using a tensile strength tester, a tensile test is performed at a grip interval of 100 mm and a tensile speed of 100 mm / min, and the stress at the time of 3% elongation (F1) in the machine direction and the stress at the time of 5% elongation (F2) are measured. did. Where F1 is 5 cm wide,
Stress when converted per unit weight of 1 g / m ² (unit: gf)
And F2 is the stress (unit: gf) per 5 cm width without conversion into basis weight.

[Strength at Break and Elongation at Break] A test piece having a length of 15 cm in the machine direction and a width of 5 cm is cut from the nonwoven fabric. Using a tensile strength tester, grip distance 100m
m, a tensile test was performed under the conditions of a tensile speed of 100 mm / min, and the strength at break (unit: gf) and elongation (unit:%) were measured.

[Bending degree] The length in the machine direction from the nonwoven fabric is 1
A test piece 5 cm wide and 5 cm wide is cut out. JIS-10
The bending resistance in the machine direction is measured according to the 96A method (45-degree cantilever method). Unit (mm)

[Generation of Break Angle] A test piece having a length of 15 cm in the machine direction and a width of 5 cm is cut from the nonwoven fabric. The test piece is placed on a desk, and both ends of the test piece are bent and adhered by hand. Observe the vicinity of the top of the non-woven fabric in a curved state to check for occurrence of a break angle. It is determined as “present” when a break angle occurs and “absent” when no break angle occurs.

[Hand] The touch of a 25 cm × 25 cm nonwoven fabric by five panelists was evaluated as “good” or “poor” from the viewpoint of flexibility, fluffing and the like. When three or more persons judged "good", the texture was judged "good", and in other cases, the texture was judged "poor".

Example 1 and Comparative Examples 1-3 Melt flow rate (ASTM 1238L) 15 ethylene-propylene-butene-1 copolymer (ethylene 3.0%, propylene 92.5%, butene-1,4. 5
%) As a sheath component and melt-spinning a sheath-core composite fiber having a composite ratio of 50% by weight to 50% by weight using crystalline polypropylene having a melt flow rate of 15 as a core component. This unstretched yarn is stretched 2.5 times between hot rolls at a temperature of 90 ° C. using a stretching machine, and then a fiber finish is attached thereto. Then, mechanical crimping is performed by a stuffing box type crimper, and suction is performed. Dry with a dryer, cut and fineness 2d / f, fiber length 3
8 mm staple fibers were obtained. Next, the fiber was made into a web using a card machine, and the convex shape rhombus, the convex area ratio 2
Using a thermocompression bonding device composed of a metal embossing roll and a metal flat roll of 3%, a metal embossing roll temperature of 130
℃, metal flat roll temperature 130 ℃, linear pressure 20 kgf
Under the conditions described above to obtain a nonwoven fabric (a) having a basis weight of 20 g / m ² .

The nonwoven fabric (a) was stretched in a machine direction of the nonwoven fabric at a respective stretching ratio using a stretching machine, and the nonwoven fabric of the present invention (Example 1) and the nonwoven fabrics other than the present invention (Comparative Examples 1 to 4) were used.
3) was obtained. Table 1 shows the physical property values and the like of the obtained nonwoven fabric.

The nonwoven fabric of Example 1 which had been stretched and had F1 and F2 within the specific numerical ranges defined by the present invention had a good texture, had no break angle, and had high breaking strength. . On the other hand, the non-woven fabrics of Comparative Examples 1, 2, and 3 in which F1 or F2 is out of the specific numerical range defined in the present invention even if the stretch treatment is not performed or the stretch treatment is performed, any of the texture, the breaking strength, etc. It was inferior. Comparative Example 3
Was nonwoven fabric having fluff, poor texture, and low F2 and breaking strength.

Example 2, Comparative Example 4 A composite ratio of 60% by weight (sheath) to 40 as a core component using high-density polyethylene of melt index (ASTM 1238E) 20 as a sheath component and polyethylene terephthalate having an intrinsic viscosity of 0.67 as a core component. A weight% (core) of sheath-core type composite fiber was melt spun. This undrawn yarn is drawn 3.0 between hot rolls at a temperature of 90 ° C. using a drawing machine, and then a fiber finish is attached thereto. Then, mechanical crimping is performed with a stuffing box type crimper, and a suction dryer is used. It was dried and cut to obtain staple fibers having a fineness of 2 d / f and a fiber length of 51 mm.
Next, the fiber was made into a web using a card machine, and the same thermocompression bonding apparatus as in Example 1 was used. The metal embossing roll temperature was 128 ° C, the metal flat roll temperature was 128 ° C, and the linear pressure was 2
Thermocompression bonding was performed under the condition of 0 kg / cm to obtain a nonwoven fabric (b) having a basis weight of 20 g / m ² .

This nonwoven fabric (b) was stretched in the machine direction of the nonwoven fabric using a stretching machine to obtain a nonwoven fabric of the present invention (Example 2). Table 1 shows the physical property values and the like of the obtained nonwoven fabric.

The nonwoven fabric of Example 2 which had been stretched and had F1 and F2 within the specific numerical ranges defined by the present invention had a good texture, did not have a break angle, and had high breaking strength. . On the other hand, the nonwoven fabric of Comparative Example 4 which had not been subjected to the stretching treatment had a poor texture and the like.

Example 3 and Comparative Example 5 A spunbonded long-fiber nonwoven fabric composed of monocomponent fibers was produced. Polypropylene having a melt flow rate (ASTM 1238L) of 40 was melt-spun by a spun bond method, and continuous continuous fibers having a fineness of 2 d / f were collected on a conveyor. Using a thermo-compression device consisting of a metal embossing roll having a convex shape rhombus and a convex area ratio of 15% and a metal flat roll, thermocompression bonding is performed at a metal embossing roll temperature of 135 ° C, a metal flat roll temperature of 135 ° C and a linear pressure of 80 kgf. After the treatment, a nonwoven fabric (c) having a basis weight of 25 g / m ² was obtained.

The nonwoven fabric (c) was stretched in the machine direction of the nonwoven fabric using a stretching machine to obtain a nonwoven fabric of the present invention (Example 3). Table 1 shows the physical property values and the like of the obtained nonwoven fabric.

The nonwoven fabric of Example 2 which had been subjected to the stretching treatment and in which F1 and F2 were within the specific numerical ranges defined by the present invention was a nonwoven fabric which had a good texture, did not have a break angle, and had high breaking strength. . On the other hand, the nonwoven fabric of Comparative Example 5 which had not been stretched had a poor texture and the like.

Example 4 and Comparative Example 6 A spunbonded long-fiber thermocompression-bonded nonwoven fabric made of a conjugate fiber was produced. A propylene / ethylene / copolymer (propylene 96.2% by weight, ethylene 3.26) having a melt flow rate (ASTM1238L) 18 by a composite spunbond method.
8% by weight) as a sheath component and a melt flow rate (AST).
M1238L) Spindle of a sheath-core type composite long fiber having a composite ratio of 50% by weight (sheath) to 50% by weight (core) using polypropylene of 29 as a core component, and a continuous long fiber having a fineness of 2.2 d / f on a conveyor. Collected. Using a thermocompression bonding device consisting of a metal embossing roll having a convex shape rhombus and a convex area ratio of 15% and a metal flat roll, thermocompression bonding is performed at a metal embossing roll temperature of 130 ° C., a metal flat roll temperature of 130 ° C., and a linear pressure of 60 kgf. After the treatment, a non-woven fabric (d) having a basis weight of 25 g / m ² was obtained.

This nonwoven fabric (d) was stretched in the machine direction of the nonwoven fabric using a stretching machine to obtain a nonwoven fabric of the present invention (Example 4). After stretching, the nonwoven fabric was subjected to a tension relaxation treatment using a tension absorbing roll. Table 1 shows the physical property values and the like of the obtained nonwoven fabric.

The nonwoven fabric of Example 4 which had been stretched and had F1 and F2 within the specific numerical ranges defined by the present invention had a good feel, had no break angle, and had a high breaking strength. . On the other hand, the nonwoven fabric of Comparative Example 6 which had not been subjected to the stretching treatment had a poor texture and the like.

Comparative Example 7 The high-density polyethylene / polyethylene terephthalate composite fiber obtained in Example 2 was heat-treated at a temperature of 140 ° C. by a through-air heat treatment machine using a carding machine. 19.8g / g
As a result, a non-woven fabric (e) having an m of ² was obtained. Table 1 shows the physical properties of the nonwoven fabric. The texture of this non-woven fabric was good, but 5%
The stress (F2) at the time of elongation was low, and a bending angle was generated.

Example 5 Using a commercially available disposable diaper, a new disposable diaper using the nonwoven fabric obtained in the above Example 1 only with the surface material of the disposable diaper was manufactured. This commercially available disposable diaper uses a polyethylene sheet as a backing material for preventing liquid leakage, a liquid absorbing material comprising pulp and a polymer water absorbing agent wrapped in a tissue on the upper part of the backing material, and a spun material as a surface material on the upper part. Bonding method A polypropylene long-fiber nonwoven fabric was used. The surface material was an embossed thermocompression-bonded nonwoven fabric. Only the surface material was removed from this disposable diaper while cutting it off with a knife. In place of the removed surface material, the thermocompression-bonded nonwoven fabric obtained in Example 1 was laminated, and the peripheral portion of the disposable diaper was thermocompressed with a width of 3 mm, and the surface material and the back surface material were thermocompressed to obtain the disposable diaper of the present invention. Was. This disposable diaper had a good texture. Further, at the time of wearing and after wearing, the surface material was not broken, and the strength in practical use was judged to be sufficient.

[0037]

[Table 1]

[0038]

The nonwoven fabric of the present invention is a stretched nonwoven fabric having a specific value of the tensile stress characteristics at low elongation. This nonwoven fabric has an effect that it has a good texture and does not have a bend angle or the like when it is bent. In addition, there are effects such as high strength of the nonwoven fabric. This nonwoven fabric can be used for disposable diapers, sanitary napkins, wipers, disposable towels, bandages, disposable warmers, and the like. A liquid absorbent article using this nonwoven fabric as a material for a disposable diaper or the like was excellent in texture and liquid absorbency.

Claims (13)

[Claims] A non-woven fabric mainly composed of thermo-adhesive fibers, which is thermocompressed to form a non-woven fabric, and then the non-woven fabric is stretched to obtain a stress F1 (F1) at 3% elongation in the machine direction. Indicates a stress when converted to a width of 5 cm and a basis weight of 1 g / m ² ) is less than 25 gf and 5%
A thermocompression-bonded nonwoven fabric having an elongation stress F2 (F2 indicates a stress per 5 cm width) of 500 gf or more. 2. The thermocompression-bonded nonwoven fabric has a length of 15c in the machine direction.
2. The thermocompression-bonded nonwoven fabric according to claim 1, wherein a nonwoven fabric test piece having a width of 5 cm and a width of 5 cm is formed, and when the test piece is curved to form a loop, no bend angle occurs. 3. The thermocompression-bonded nonwoven fabric according to claim 1, wherein the stretch ratio of the nonwoven fabric is 1.05 to 1.40. 4. The thermocompression-bonded nonwoven fabric according to claim 1, wherein the thermoadhesive fibers are monocomponent fibers. 5. The thermocompression-bonded nonwoven fabric according to claim 1, wherein the thermoadhesive fiber is a spunbonded filament. 6. The thermocompression-bonded nonwoven fabric according to claim 1, wherein the heat-adhesive fiber is a polyolefin-based monocomponent fiber. 7. The thermocompression-bonded nonwoven fabric according to claim 1, wherein the heat-adhesive fiber is a polypropylene monocomponent fiber. 8. The method according to claim 1, wherein the heat-adhesive fiber is a conjugate fiber.
The thermocompression-bonded nonwoven fabric according to any one of 2, 3, and 5. 9. A heat-adhesive conjugate fiber comprising a low-melting thermoplastic resin having a melting point difference of 15 ° C. or more and a high-melting thermoplastic resin, wherein the low-melting thermoplastic resin forms at least a part of the fiber surface. The thermocompression-bonded nonwoven fabric according to claim 8, which is: 10. The thermocompression-bonded nonwoven fabric according to claim 8, wherein the conjugate fiber is a sheath-core or side-by-side thermoadhesive conjugate fiber composed of a low-melting-point polyolefin-based resin and a high-melting-point polyolefin-based resin. 11. The thermocompression-bonded nonwoven fabric according to claim 8, wherein the conjugate fiber is a sheath-core or side-by-side thermoadhesive conjugate fiber composed of a polyolefin resin and a polyester resin. 12. The thermocompression-bonded nonwoven fabric according to claim 8, wherein the conjugate fiber is a sheath-core or side-by-side thermoadhesive conjugate fiber composed of a low-melting polyester resin and a high-melting polyester resin. 13. An absorbent article using the thermocompression bonding nonwoven fabric according to claim 1.