JP2000265351A - Elastic non-woven fabric having excellent heat sealing property and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an elastic nonwoven fabric which has excellent elasticity, a good skin touch, and an excellent heat sealing property, and is suitable for sanitary materials such as diapers, disposable underwear, supporters, cataplasm base fabrics, and the like. SOLUTION: This elastic non-woven fabric having an excellent heat sealing property is obtained by applying a high pressure fluid treatment to a fiber web comprising latent crimpable conjugate fibers 1 and thermally adhesive fibers to three-dimensionally interlace the constituting fibers each other and then thermally treating the interlaced fiber web at a temperature not thermally adhering the constituting fibers each other, thereby expressing the three- dimensional crimps of the latent crimpable conjugate fibers 1. The latent crimpable conjugate fibers 1 comprise two or more kinds of polymers having different melting points, respectively, and express the three-dimensional crimps 2, when thermally treated. The thermally adhesive fibers have a higher melting point TBL( deg.C) than a temperature T( deg.C) at which the latent crimpable conjugate fibers 1 express crimps in an amount of >=17 crimps/25 mm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nonwoven fabric which is excellent in elasticity, feels good and heat sealability, and is used for sanitary materials such as diaper members, disposable underwear,
The present invention relates to a stretchable nonwoven fabric suitable for a supporter, a poultice base fabric, and the like.

[0002]

2. Description of the Related Art Conventionally, stretchable nonwoven fabrics have been used for various applications. In particular, in applications where a human body is touched, there has been a demand for a nonwoven fabric that fits easily to the human body and has a good touch. In addition, heat-sealing properties are also required for disposable underwear and the like. In the above applications, stretchable nonwoven fabrics mainly composed of latently crimpable short fibers are preferably used because of their excellent touch, and various proposals have been made for these. For example, JP-A-2-127553 discloses a web mainly composed of a polypropylene-based heat-adhesive conjugate fiber,
A stretchable nonwoven fabric has been proposed in which the fibers are entangled by a water needle method, heat-treated to shrink the web, and fibers are adhered to each other. JP-A-2-182957 discloses a stretchable nonwoven fabric comprising a mixture of a polyester-based latently crimpable conjugate fiber and a heat-adhesive short fiber made of a polyethylene terephthalate-based low-melting polymer, which is subjected to heat bonding and crimp development treatment. Has been proposed. Also, Japanese Patent Application Laid-Open
Japanese Patent Publication No. 132861 discloses a thermoadhesive composition containing a composite fiber composed of a polyolefin / polyester having a number of crimps of 20/25 mm or less and a composite fiber composed of a polyolefin / polyester having a crimp number of 40/25 mm or more. A nonwoven fabric is disclosed.

[0003]

However, the above-mentioned nonwoven fabric has the following problems. JP-A-2-127
553 and JP-A-2-182957, all of the fibers are heat-bonded to each other at the same time as crimping, so that not only the elasticity is easily hindered, but also a rugged feel and a soft touch are obtained. Not good. Furthermore, since heat sealing properties are not considered,
There is a problem in terms of process or cost such that sufficient heat sealing strength cannot be obtained when treated at a low temperature.
Further, the non-woven fabric disclosed in Japanese Patent Application Laid-Open No. 1-128661 is also heat-bonded in the same manner as described above, and further uses a composite fiber composed of a combination of heterogeneous polymers, so that the heat seal strength is insufficient. The present invention has been made in view of the above problems, and has an object to provide a stretchable nonwoven fabric that is excellent in stretchability, has a good touch, and is excellent in heat sealability and is suitable for various uses. I do.

[0004]

The stretchable nonwoven fabric of the present invention
In order to solve the above-mentioned conventional problems, 2
Consists of more than two types of polymers, and generates three-dimensional crimps by heat treatment
A latently crimpable conjugate fiber (hereinafter referred to as S fiber),
Fibers containing heat-adhesive fibers (hereinafter referred to as B fibers)
Web is a three-dimensionally entangled non-woven fabric,
It is characterized by satisfying the configuration. (A) S-fiber crevices three-dimensional crimps 17 crimps / 25mm or more
Melting point TS higher than temperature T (° C)_L(℃)
Resin as the first component, TS_LMelting point TS higher than 5 ℃
_H(C) as the second component, the first component
And the second component are arranged in parallel, or the first component is sheathed.
Latent crimp arranged in an eccentric sheath-core type with the second component as the core
It should be a composite fiber. (B) B fiber has a melting point TB higher than the temperature T (° C.)
_L(° C) as a low melting point component, thermal bonding satisfying the following relationship
It must be synthetic fiber. TS_L-20 ≤ TB_L ≤ TS_L+20 (c) Three-dimensional crimping of S fibers with a crimp count of 17 / 25mm or more
And the constituent fibers are substantially thermally bonded to each other.
Not that. By adopting such a configuration, the elasticity is hindered.
And feels good, and at the same time has strong heat sealing
A rich stretchable nonwoven fabric is obtained.

[0005] In the fibers constituting the stretchable nonwoven fabric of the present invention, S fibers are 50 to 80% by weight, and B fibers are 50 to 20% by weight.
Desirably, it is contained by weight.

[0006] The B fibers, the melting point TB _L resin consisting of (℃) as the sheath component, TB _L than 10 ° C. or more higher than the melting point TB _H (℃)
Concentric sheath-core type composite fibers containing a resin consisting of Further, it is desirable that the first component of the S fiber and the low melting point component of the B fiber are made of the same resin.

Further, the stretchable nonwoven fabric of the present invention is rich in stretchability and water absorption when a fibrous web containing hydrophilic fibers is laminated on at least one surface of the fibrous web,
In addition, a stretchable nonwoven fabric having excellent heat sealability is obtained, which is convenient. It is preferable that the fibrous web containing the hydrophilic fiber contains 50 to 10% by weight of the hydrophilic fiber and 50 to 90% by weight of the latently crimpable conjugate fiber since sufficient elasticity can be obtained.

The nonwoven fabric has an open area of 0.25 to 30 mm ²
It is preferred that the nonwoven fabric having the openings formed therein has a woven-like feel to the touch and improves air permeability.

The elongation at break in the longitudinal and transverse directions of the stretchable nonwoven fabric of the present invention is at least 100%, and the 50% modulus in the transverse direction of the nonwoven fabric is 0.7 cN / 50 mm.
It is desirable that:

[0010] The stretchable nonwoven fabric of the present invention is composed of two or more polymers having different melting points. the fibrous web containing the B fiber 50 to 20 wt% with higher melting point TB _L (° C.) temperature T (° C.) expressing pieces / 25mm or more, the constituent fibers to each other three-dimensionally by applying a high pressure fluid flow treatment It can be manufactured by entanglement, followed by a heat treatment at a temperature at which the constituent fibers do not have thermal bonding, and then the S fibers are three-dimensionally crimped.

As another method, 50 to 80% by weight of S fiber, which is made of two or more polymers having different melting points and develops three-dimensional crimp by heat treatment, and the number of crimps of S fiber is 17%
Melting point TB higher than the temperature T (° C) at which the temperature is expressed per piece / 25mm or more
A fiber web containing 50 to 20% by weight of a B fiber having _L (° C.), a fiber web containing 50 to 10% by weight of a hydrophilic fiber and 50 to 90% by weight of a latent crimpable conjugate fiber are laminated. The constituent fibers are three-dimensionally entangled and integrated by performing a fluid flow treatment, and then subjected to a heat treatment at a temperature at which the constituent fibers do not have thermal adhesion, so that the S fibers and / or the latently crimpable composite By expressing the fibers in a three-dimensional crimp, a stretchable nonwoven fabric excellent in heat sealability and water absorption can be obtained. Hereinafter, the contents of the present invention will be specifically described.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The latently crimpable conjugate fiber (hereinafter referred to as "S fiber") used in the present invention is composed of two or more polymers having different melting points, and develops three-dimensional crimp by heat treatment. At the temperature T (° C.), it is preferable that the number of crimps of the S fiber is 17 or more / 25 mm. More preferably, the expression is 30/25 mm or more. As used herein, the term “three-dimensional crimp” refers to not only a spiral crimp, but also a two-dimensionally bent one that draws a gentle curve as shown in FIGS. It is intended to include a case where a three-dimensional curved portion is added to a natural bend, and is a word used to distinguish it from a mechanical crimp given by a crimper or the like. If the number of crimps of the S fiber is less than 17/25 mm, the resulting nonwoven fabric has insufficient elasticity and poor durability. Examples of the S fibers satisfying the range of the number of crimps include conjugate fibers having a parallel or eccentric core-sheath cross section. For example, copolymerized polyester / polyethylene terephthalate, ethylene-propylene copolymer / polypropylene and ethylene- Propylene-based copolymers such as butene-1-propylene terpolymer / polypropylene / polypropylene, composite fibers such as polyethylene / polyethylene terephthalate, polyethylene / polybutylene terephthalate, and the like. The above can be selected and used.

In particular, the S fiber has a resin having a melting point of TS _L (° C.) as a first component and has a melting point TS higher than T _SL by 5 ° C. or more.
_{When the} resin composed of _H (° C.) is used as the second component, the first component and the second component are arranged in a side-by-side configuration, or are arranged in an eccentric sheath-core configuration in which the first component is a sheath and the second component is a core. Is preferably a latently crimpable conjugate fiber, such as copolymerized polyester / polyethylene terephthalate, ethylene-propylene copolymer / polypropylene, and ethylene-butene-1-.
A propylene terpolymer / polypropylene combination is preferred in that a high number of crimps can be obtained at low temperatures.

Next, a thermoadhesive fiber (hereinafter referred to as a B fiber) mixed with the S fiber as a fibrous web has a temperature T.
(℃) higher than the melting point TB _L (℃) and low melting point component is preferably a heat-bondable fibers to satisfy the following relation. When meeting the _{TS L -20 ≦ TB L ≦ TS} L +20 above relationship, while maintaining a soft texture, such as stretch and soft, preferable in that excellent heat-sealing properties is obtained. More preferably, TB _L is (TS _L -10)
To (TS _L +10), and more preferably, the first component of the S fiber and the low melting point component of the B fiber are made of the same resin. Here, the term “identical resin” refers to a concept that excludes resins having obviously different structures, and excludes resins having a difference of 5% by weight or more in the content of a copolymer component if the resin contains a copolymer component. is there. If TB _L is less than TS _L -20, S
Fiber ends up B fiber fusion in less sufficiently crimp development, excellent non-woven fabric can not be obtained in elasticity, TB _L is TS _L +2
If it exceeds 0, not only is it inferior to low-temperature heat sealability,
This is because sufficient heat sealing strength may not be obtained.

The form of the B-fiber may be any of a single form, a composite form of a circle and a modified form, and in the case of a composite form, the resin is a mixed type having at least one component, a fiber section is a parallel type, and an eccentric sheath. Core type, concentric sheath core type, split type,
Sea-island type and the like. Among them, the melting point TB _L resin consisting of (℃) as the sheath component, TB _L than 10 ° C. or more higher than the melting point T
It is preferably a concentric sheath-core composite fiber containing a resin composed of _BH (° C) as a core component. For example, polyethylene / polypropylene, ethylene-propylene copolymer / polypropylene, ethylene-butene-1-propylene terpolymer / polypropylene, polyethylene / polyethylene terephthalate and the like can be mentioned. In particular, when the first component of the S fiber and the sheath component of the concentric sheath-core type heat-adhesive conjugate fiber are made of the same resin, high heat sealing properties can be obtained, which is preferable.

In the above fibrous web, the S fiber is 50 to 50%.
It is preferable to contain 80% by weight and 50 to 20% by weight of the B fiber. If the S fiber is less than 50% by weight or the B fiber exceeds 50% by weight, sufficient elasticity cannot be obtained, and the S fiber exceeds 80% by weight or the B fiber contains 20% by weight.
If it is less than this, sufficient heat sealing properties cannot be obtained.

In the fibrous web, if necessary, materials other than the S fiber and the B fiber may be mixed.
The S fiber is not particularly limited as long as it has an adhesive property when the number of crimps of the S fiber is 17 pieces / 25 mm or more.
Examples of the material include natural fibers such as cotton and silk, regenerated fibers such as rayon, semi-synthetic fibers such as acetate, acrylic fibers, polyamide fibers such as nylon 6, nylon 66, polyethylene terephthalate, and polybutylene terephthalate. Polyester-based fibers such as polyester fibers, polyethylene, and polypropylene, and the like, and the fiber shape is not particularly limited, single fibers, sheath-core composite fibers,
Examples thereof include splittable conjugate fibers and modified cross-section fibers, and one or more of these may be arbitrarily selected and used.

In the stretchable nonwoven fabric of the present invention, a fiber web containing hydrophilic fibers may be laminated on at least one surface of the fiber web. The laminating method may be either a fibrous web state or a nonwoven fabric form, but it is preferable to laminate in a fibrous web state in consideration of the entanglement property when three-dimensionally entangled as described later. When a fiber web containing hydrophilic fibers is laminated, a stretchable nonwoven fabric having excellent stretchability and water absorption and excellent heat sealability can be obtained, which is convenient. As hydrophilic fibers, cotton,
Natural fibers such as silk and wool, regenerated fibers such as rayon, semi-synthetic fibers such as acetate, acrylic fibers, and synthetic fibers subjected to a hydrophilic treatment are exemplified.

The fibrous web containing the hydrophilic fibers,
It is preferable to contain 50 to 10% by weight of a hydrophilic fiber and 50 to 90% by weight of a latent crimpable conjugate fiber. The latently crimpable conjugate fiber mentioned here may be the above-mentioned S fiber or another fiber. However, in order to improve the heat sealing property, it is preferable to use the S fiber. If the hydrophilic fiber is less than 10% by weight or the latent crimping conjugate fiber exceeds 90% by weight, the hydrophilicity is insufficient, and the hydrophilic fiber exceeds 50% by weight or the latent crimping conjugate fiber is less than 50% by weight. 5
If the amount is less than 0% by weight, the elasticity of the nonwoven fabric becomes insufficient.

Next, a method for producing a stretchable nonwoven fabric of the present invention will be described. The form of the fibrous web is not particularly limited, and examples thereof include a parallel web made of staple fibers, a semi-random web, a random web, and a spunbonded web made of long fibers. Then, fiber length 25-80
Staple fibers of mm are preferred. Further, when laminated with a fiber web containing hydrophilic fibers as described above,
It is advisable to stack the layers before performing a high-pressure fluid flow treatment described later.

The basis weight of the fibrous web is determined according to the use of the finally obtained elastic nonwoven fabric. For example, when used for diaper members such as diaper back sheets, 1
A fibrous web of 0-120 g / m ² may be formed.

Then, the fibrous web is three-dimensionally entangled. Examples of the entanglement method include a needle punching method and a high-pressure fluid flow method. If emphasis is placed on the feeling, the high-pressure water flow method is suitable. The water injected at this time may be a columnar flow or a radial flow. For example, in the case of a high pressure columnar flow, the orifice having a hole diameter of 0.05 to 2 mm is used in the case of a high pressure columnar flow. 5-5
It is good to spray at a pressure of 1 to 10 MPa from a nozzle provided in mm.

At this time, the fibrous web may be placed on a support for forming openings to perform high-pressure fluid flow treatment. When such a treatment is performed, the nonwoven fabric has an open area of 0.25 to 30 mm ^2.
A large number of openings are formed, and a nonwoven fabric excellent in design and air permeability can be obtained. Examples of the support for forming openings include a pattern net formed by weaving monofilaments and metal wires, and a roll provided with protrusions. The shape of the obtained aperture is not particularly limited, and may be any of a circle, an ellipse, a rhombus, a rectangle, and the like, and the aperture pattern may be any of a zigzag, a lattice, and the like.

The obtained entangled nonwoven fabric is subjected to a heat treatment at a temperature at which the constituent fibers do not have a thermal bond, so that the S fibers are three-dimensionally crimped, and the stretchable nonwoven fabric has no constituent fibers substantially thermally bonded. And Here, the term “substantially not thermally bonded” is a concept that includes the adhesion between fibers due to softening of the resin and does not include at least a part of the resin that is melted. The heat treatment temperature is above the temperature T (° C.) at which the number of crimps is expressed as 17 pieces / 25 mm or more, and the melting point TS _L (° C.) of the S fiber.
And B melting point TB _L (° C.) of the fiber may be heat treated at a temperature below. The heat treatment is performed using a pin tenter, a clip tenter, a conveyor-type hot-air treatment machine, or the like, in a relaxed state or in a tension state in at least one direction. In particular, when imparting elasticity to the entire surface of the nonwoven fabric, the heat treatment is preferably performed in a relaxed state.
0 to 150% overfeed, 0
When contracted by 50%, a stretchable nonwoven fabric having good stretchability and texture can be obtained.

The elongation at break of the stretchable nonwoven fabric thus obtained in the longitudinal and transverse directions is at least 10
Preferably, it is 0% and the 50% modulus in the transverse direction of the nonwoven fabric is 0.7 cN / 50 mm or less. Elongation at break less than 100% and 50% modulus 0.7cN / 50mm
Exceeding the range is not preferable because the nonwoven fabric does not follow the movement of the body and has a feeling of pressure.

The stretchable nonwoven fabric of the present invention may be laminated on a fibrous web, a nonwoven fabric composed of short fibers or long fibers, a knitted fabric, a net, a film, or the like, or may be laminated or laminated on itself. When heat-sealing at a temperature higher than the softening point of the constituent fibers, the effect is sufficiently exerted, the peeling strength in the heat-sealed part is excellent, and the high stretchability and good texture are maintained in the non-heat-sealed part. Become.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the contents of the present invention will be described with reference to embodiments. The number of crimps, melting point, tensile strength, elongation at break, 50% modulus, and heat seal strength of the obtained elastic nonwoven fabric were measured by the following methods.

[Number of crimps] First, about 200 fibers were bundled,
One end (approximately 2 mm from the end) of the fiber bundle is tied with a cotton thread, and the other end is unloaded and suspended in a dryer. Next, the temperature inside the dryer is gradually increased, and after maintaining a constant temperature state at a predetermined temperature for 5 minutes, five fibers are taken out of the fiber bundle, and this operation is repeated every 10 ° C. And JIS L 10
According to No. 15, the number of crimps of the fiber taken out was measured.

[Melting Point (DSC Measurement)] Using SSC-5000 manufactured by Seiko Denshi Kogyo Co., Ltd., 6 mg of fiber was measured at a heating rate of 10 ° C./min under nitrogen gas conditions.

[Tensile Strength, Elongation at Break] A constant speed elongation type tensile tester (trade name: 3 using Tensilon Orientec Co., Ltd.
The film was stretched at a speed of 0 cm / min, and the load value at the time of cutting was defined as tensile strength.

[50% Modulus] A sample piece having a width of 5 cm and a length of 15 cm, the length of which is the transverse direction of the composite sheet, is gripped at a gripping interval of 10 cm, and 30 cm / cm is measured using the above constant-speed elongation type tensile tester. The load value at the time of 50% elongation at the speed of minutes was defined as 50% modulus.

[Heat Seal Strength] Two specimens each having a width of 2.5 cm and a length of 15 cm, whose length is in the horizontal direction, are prepared and superposed. Lengthwise end 3 of superimposed sample pieces
In the width direction at the position of cm, heat seal machine (heat seal tester vertical temperature control TYPE "TP-701-B" Tester Sangyo Co., Ltd.
Was heat-sealed at a heat seal width of 2 mm, a temperature of 165 ° C., a pressure of 6.1 kg / cm ² , and 0.4 seconds. Then, the sample piece after the heat sealing is grasped at an interval of 10
cm, and 10 cm using the constant-speed extension type tensile tester.
The average of the load values at a maximum of 3 points and a minimum of 3 points at the time of elongation at a rate of / min, which is a total of 6 points, was defined as the heat sealing strength.

[0033] [Example 1] S fiber, the sheath component TS _L
= Of 142 ° C. Ethylene - a propylene copolymer, a core component and TS _H = 163 ° C. polypropylene, reduced number of winding in these arrangement temperatures T = 130 ° C. in an eccentric sheath-core type 20 / 25mm stereoscopic Fineness of 2.2 dte with crimp development
x, 70% by weight of a polypropylene-based latent crimpable conjugate fiber (manufactured by Daiwa Spinning Co., Ltd.) having a fiber length of 51 mm as B fiber,
Ethylene sheath component TB _L = 142 ℃ - a propylene copolymer, a core component and TB _H = 163 ° C. polypropylene, fineness they are arranged concentrically sheath-core type 2.2dte
x, a parallel web with a basis weight of 40 g / m ² consisting of 30% by weight of a polypropylene-based composite fiber (manufactured by Daiwa Spinning Co., Ltd.) having a fiber length of 51 mm. The fiber web has a pore size of 0.
A water stream of 3 MPa was jetted twice from each of the nozzles having 12 mm orifices at 0.6 mm intervals on each of the front and back sides of the laminate to form an entangled body, and then dried at 70 ° C. to form an entangled sheet.

Next, using a pin tenter, heat-treating temperature is 135 ° C., and over-feed is performed 65% in the vertical direction.
The entangled sheet was subjected to a heat treatment to obtain a stretchable nonwoven fabric having a basis weight of 70 g / m ^{2 in which} the constituent fibers were not thermally bonded.

[Example 2] A water stream of 2 MPa was jetted twice from a nozzle in which orifices having a hole diameter of 0.12 mm were drilled at intervals of 0.6 mm to the fiber web of Example 1 twice for each of the front and back sides of the laminate to perform preliminary entanglement. After being integrated, a water stream with a water pressure of 7 MPa is injected from a nozzle provided with orifices having a hole diameter of 0.12 mm at intervals of 0.6 mm on a support for forming pores (25-mesh plain fabric manufactured by Nippon Filcon Co., Ltd.). Then, after forming an opening, it was dried at 70 ° C. to form an entangled sheet. Then
Using a pin tenter to give a heat treatment temperature of 135 ° C., in the longitudinal direction is 65% overfeed, subjected to heat treatment entangled sheet, a stretchable opening nonwoven fabric constituting fibers having a basis weight of 70 g / m ² is not heat-bonded Was. The average open area of the obtained nonwoven fabric was 2 mm ² , and the open area ratio was 13%.

Example 3 A parallel web made of the same combination as in Example 1 except that the basis weight was set to 20 g / m ² was used as the first fibrous web. 70% by weight of crimpable conjugate fiber (manufactured by Daiwa Spinning Co., Ltd.), rayon fiber having a fineness of 1.67 dtex and a fiber length of 40 mm (Daiwabo Rayon Co., Ltd.)
Was produced as a second fiber web using a parallel web composed of 30% by weight and having a basis weight of 20 g / m ² . Then, the fiber web obtained by laminating the first fiber web and the second fiber web has a pore size of 0.12.
A water stream of 3 MPa is jetted once from each of the front and back sides of the laminated body from a nozzle in which orifices of 0.6 mm are bored at intervals of 0.6 mm to perform pre-entanglement and integration, and then a support for forming an opening (Nippon Filcon Co., Ltd.) 25 woven fabric), with a pore size of 0.12
After a water stream with a water pressure of 7 MPa is jetted from a nozzle provided with 0.6 mm orifices at 0.6 mm intervals to form openings,
It was dried at 0 ° C. to form an entangled sheet. Then, by using a pin tenter, heat treatment temperature 135 ° C., longitudinally direction by 65% overfeed, subjected to heat treatment entangled sheet, stretchable opening nonwoven fabric constituting fibers having a basis weight of 70 g / m ² is not heat-bonded I got The average opening area of the obtained nonwoven fabric was 2 mm ² , and the opening ratio was 13%.

[0037] [Comparative Example 1] B fiber, the sheath component TB _L
= High-density polyethylene at 132 ° C and core component TB _H =
Example 2 except that polypropylene was used at 163 ° C., and these were heat-adhesive composite fibers (manufactured by Daiwa Spinning Co., Ltd.) having a concentric sheath-core type of 2.2 dtex and a fiber length of 51 mm.
In the same manner as described above, a stretched open nonwoven fabric was obtained in which constituent fibers having a basis weight of 70 g / m ² were thermally bonded to each other. The average open area of the obtained nonwoven fabric was 2 mm ² , and the open area ratio was 13%.

Comparative Example 2 As the S fiber, the polypropylene-based latently crimpable conjugate fiber of Example 1 (Daiwa Spinning Co., Ltd.)
70% by weight, a rayon fiber having a fineness of 1.67 dtex and a fiber length of 40 mm (manufactured by Daiwabo Rayon Co., Ltd.) was changed to 30% by weight in the same manner as in Example 2 except that the basis weight was 70 g / g.
Configuration fibers of m ² was obtained stretchable opening nonwoven fabric which has not been heat-bonded. The average open area of the obtained nonwoven fabric was 3 mm ² , and the open area ratio was 13%. Table 1 shows various performances of Examples 1 to 3 and Comparative Examples 1 and 2.

[0039]

[Table 1]

In Examples 1 to 3, the polypropylene-based latently crimpable conjugate fiber (S fiber) was crimped and the constituent fibers were not thermally bonded to each other, so that a non-woven fabric excellent in elasticity was obtained. When this was heat-sealed, it could be firmly adhered. Example 2
In Example 3, the openings were formed and the air permeability was excellent. On the other hand, in Comparative Example 1, since the heat treatment was performed at a temperature equal to or higher than the melting point of the heat-adhesive conjugate fiber (B fiber), the constituent fibers were bonded to each other, and although the heat sealing strength was excellent,
Not only the elasticity is impaired, but also the texture is hard, and it is not suitable for uses such as diaper members that come in contact with human skin. In Comparative Example 2, the heat-sealing strength was extremely reduced because no heat-adhesive fiber (B fiber) was present.

[0041]

The stretchable nonwoven fabric of the present invention uses a fiber web composed of a specific latent crimpable conjugate fiber and a heat-adhesive fiber, and the number of crimps of the latent crimpable conjugate fiber is 17/25 mm or more. Since a three-dimensional crimp is developed and the constituent fibers are not substantially thermally bonded to each other, a stretchable nonwoven fabric that has a good touch and a high heat-sealing strength without obstructing stretchability can be obtained. In addition, when a fiber web containing hydrophilic fibers is laminated on at least one surface of the fiber web, a stretchable nonwoven fabric which is rich in stretchability and water absorption and excellent in heat sealability can be obtained.

[0042] Furthermore, the stretchable nonwoven fabric of the present invention, by the opening nonwoven fabric obtained by forming an opening of the open area 0.25～30Mm ^2, touch is woven like, highly breathable stretch A nonwoven fabric is obtained. The stretchable nonwoven fabric of the present invention is suitable for, for example, sanitary materials such as diaper members, disposable undergarments, supporters, cataplasms and the like.

[Brief description of the drawings]

FIG. 1 shows an example of a crimped form in a three-dimensional crimpable fiber used in the present invention.

FIG. 2 shows another example of a crimped form in the three-dimensionally crimpable fiber used in the present invention.

FIG. 3 shows another example of a crimped form in the three-dimensionally crimpable fiber used in the present invention.

[Explanation of symbols]

 1 Latent crimped conjugate fiber 2 3D crimp

Claims (10)

[Claims] 1. A method comprising two or more polymers having different melting points.
Latently crimped composite fiber
Wei (hereinafter referred to as S fiber) and heat-adhesive fiber (hereinafter referred to as B fiber)
Fibrous web containing fibers)
Characterized by satisfying the following configuration
Stretch nonwoven fabric with excellent heat sealability. (A) S-fiber crevices three-dimensional crimps 17 crimps / 25mm or more
Melting point TS higher than temperature T (° C)_L(℃)
Resin as the first component, TS_LMelting point TS higher than 5 ℃
_H(C) as the second component, the first component
And the second component are arranged in parallel, or the first component is sheathed.
Latent crimp arranged in an eccentric sheath-core type with the second component as the core
It should be a composite fiber. (B) B fiber has a melting point TB higher than the temperature T (° C.)
_L(° C) as a low melting point component, thermal bonding satisfying the following relationship
It must be synthetic fiber. TS_L-20 ≤ TB_L ≤ TS_L+20 (c) Three-dimensional crimping of S fibers with a crimp count of 17 / 25mm or more
As well as the constituent fibers are substantially thermally bonded
Not that. 2. The S fiber is 50 to 80% by weight and the B fiber is 5% by weight.
The stretchable nonwoven fabric having excellent heat sealability according to claim 1, which contains 0 to 20% by weight. Wherein B fibers, the melting point TB _L a low melting point resin comprising (℃) as the sheath component, TB _L than 10 ° C. or more higher than the melting point TB
_The stretchable nonwoven fabric having excellent heat-sealing properties according to claim 1 or 2, wherein the stretchable nonwoven fabric is a concentric sheath-core composite fiber having a core component of a high melting point resin composed of _H (° C). 4. The heat-sealing stretchable nonwoven fabric according to claim 1, wherein the first component of the S fiber and the low melting point component of the B fiber are made of the same resin. 5. A stretchable nonwoven fabric having excellent heat sealing properties, wherein a fibrous web containing hydrophilic fibers is laminated on at least one surface of the fibrous web according to any one of claims 1 to 4. 6. A fibrous web containing hydrophilic fibers, comprising 50 to 10% by weight of hydrophilic fibers and 5 to 5% of latently crimpable conjugate fibers.
The stretchable nonwoven fabric excellent in heat sealability according to claim 5, which contains 0 to 90% by weight. 7. The heat-sealing property according to claim 1, wherein the non-woven fabric is an open non-woven fabric having an opening having an opening area of 0.25 to 30 mm ² . Stretch nonwoven. 8. The nonwoven fabric according to claim 1, wherein the elongation at break in the machine direction and the transverse direction is at least 100%, and the 50% modulus in the transverse direction of the nonwoven fabric is 0.7 cN / 50 mm or less. 7. The stretchable nonwoven fabric according to any one of 7 above, which is excellent in heat sealability. 9. S-fibers 50 to 80 comprising two or more kinds of polymers having different melting points and exhibiting a three-dimensional crimp by heat treatment.
B fiber 50 having a weight percent, the temperature reduced number winding of S fibers express 17 / 25mm or more T a (℃) higher than the melting point TB _L (℃)
The fiber web containing ２０20% by weight is subjected to a high-pressure fluid flow treatment so that the constituent fibers are three-dimensionally entangled, and then subjected to a heat treatment at a temperature at which the constituent fibers do not have thermal adhesion. A method for producing a stretchable nonwoven fabric having excellent heat sealability, characterized in that fibers are three-dimensionally crimped. 10. S fibers 50 to 8 comprising two or more kinds of polymers having different melting points and exhibiting three-dimensional crimp by heat treatment.
B fiber 5 having 0% by weight and a melting point TB _L (° C.) higher than the temperature T (° C.) at which the number of crimps of the S fiber is 17 pieces / 25 mm or more
A fibrous web containing from 0 to 20% by weight;
0 to 10% by weight and 50 to 90% by weight of latently crimpable conjugate fiber
Are laminated and subjected to a high-pressure fluid flow treatment to entangle and integrate the constituent fibers three-dimensionally, and then heat-treated at a temperature at which the constituent fibers do not have thermal adhesion, A method for producing a stretchable nonwoven fabric having excellent heat sealability, characterized in that fibers and / or the latently crimpable conjugate fibers are expressed in three-dimensional crimps.