JP2002173862A - Composite nonwoven fabric and textile product using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composite nonwoven fabric and fiber product using the same having feeling of a nonwoven fabric and strength of bond between laminated nonwoven fabrics and resistance to fluff. SOLUTION: This composite nonwoven fabric uses a nonwoven fiber assembly (I) comprising a thermoplastic resin (A) as a base layer and laminating a nonwoven fiber assembly (II) comprising a thermoplastic resin (A') having melting point 2 to 17 deg.C higher than the melting point of the thermoplastic resin (A) of the same kind, at least one side of the base layer and the nonwoven fiber assembly (I) and the nonwoven fiber assembly (II) are hot bonded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite nonwoven fabric which has a very soft feel, does not peel between non-woven fiber aggregate layers, and has fuzz resistance, and a fiber product using the same.

[0002]

2. Description of the Related Art Nonwoven fabrics obtained by thermocompression bonding using thermoplastic fibers as raw materials have good productivity and are excellent in cost, and have good soft texture and high nonwoven fabric characteristics (high nonwoven fabric strength). Rarely used for sanitary materials. However, as a recent tendency, a softer texture (tactile sensation) is required for the surface material of the safety material. In addition, regarding the fuzz resistance of the nonwoven fabric, which is a problem when the nonwoven fabric is used for the top sheet and the backsheet of the disposable diaper, it is an important quality item of the nonwoven product together with the strength and texture of the nonwoven fabric. Has been requested.

[0003] Since a nonwoven fabric which satisfies all of the fuzz resistance, the strength of the nonwoven fabric, and the texture is difficult to obtain with a single-layer nonwoven fabric, improvement of the above-mentioned quality items by a composite nonwoven fabric in which a plurality of types of nonwoven fabrics are laminated has been studied. I have. For example, JP-A-5-33257 discloses that a polyethylene terephthalate long fiber is provided between two nonwoven fabric layers composed of a sheath-core type composite long fiber having polyethylene terephthalate as a core component and high-density polyethylene as a sheath component. A composite nonwoven fabric having a three-layer structure in which a nonwoven fabric layer is present and in which the entire nonwoven fabric is partially thermocompression-bonded has been proposed.

In this method, the polyethylene terephthalate long fibers in the middle layer are about 100 to 1 times smaller than the fibers in the upper and lower layers.
Since it is made of a thermoplastic resin having a melting point of 30 ° C. or higher, the middle layer has little adhesion between fibers even when partially thermocompression-bonded,
The degree of freedom of the long fiber is relatively high. At this time, since the fibers in the middle layer are not bonded, the flexibility of the nonwoven fabric is improved, but the strength of the nonwoven fabric is insufficient. Therefore, in order to obtain sufficient nonwoven fabric strength, the fibers of the upper and lower layers must be treated at a higher temperature, and by treating under such conditions, fusion of the resin component to the thermocompression bonding roll occurs. Problem had arisen. Furthermore, the compatibility between the different types of resins is poor because of the thermal bonding between the different types of resins, and as a result, the adhesion between the laminations becomes insufficient. The problem remained.

In order to make up for this drawback, Japanese Patent Application Laid-Open No.
No. 8 discloses a long fiber group A and a long fiber between a portion consisting only of a long fiber group A and an interlayer consisting of only a long fiber group B consisting of a polymer component having a melting point higher than that of the long fiber group A by 20 ° C. Group B
Have entangled and mixed portions, and a composite nonwoven fabric obtained by subjecting them to thermocompression bonding has been proposed.

According to this method, the fibers of the long fiber group A and the long fiber group B are mixed between the layers consisting of the long fiber group A and the long fiber group B only. The effect of suppressing peeling between the stacks with the group B is obtained.
However, in this method, since the melting points of the long fiber group A and the long fiber group B differ by 20 ° C. or more, it is necessary to set the processing temperature to the high melting point side or different processing temperatures for the high melting point side and the low melting point side. However, when the processing temperature is adjusted to the high melting point side, the amount of heat applied to the low melting point side becomes excessive, causing a problem that the thermoplastic resin constituting the long fiber group is fused to the processing device. Next, when different processing temperatures are set for the high melting point side and the low melting point side, respectively, the amount of heat applied to the mixed portion as the middle layer tends to be insufficient, and there has been a problem that separation between the layers occurs. In addition, since the middle layer has a structure in which the long fiber group A and the long fiber group B having different melting points are mixed, there are few fused portions sufficient for self-adhesion and adhesion between laminations. And there was a problem in nonwoven fabric strength and fuzz resistance.

Further, Japanese Patent No. 3043099 discloses that
A layer 1 composed of only the composite conjugate fiber A having a polymer component a1 exposed on the fiber surface, and a polymer component b1 exposed on the fiber surface, wherein b1 has a melting point of the polymer component a1 of 20 or more. There is a layer 4 composed of only the composite filament B higher than at least
Discloses a composite nonwoven fabric which is a layer in which the fiber weight ratio per unit volume of the composite long fiber group A and the composite long fiber group B is continuously changed (hereinafter, referred to as a mixed fiber portion). In this method, the formation of the mixed fibers is not uniform, and the mixed fibers are uneven, such as the ratio of the composite long fibers A and the composite long fibers B in the mixed fibers is uneven, so that the adhesion between the layers is deteriorated. As a result, peeling between layers has been a problem. Also, in this method, since the melting point of the layer 1 composed of only the composite filament A and the layer 4 composed of only the composite filament B differ by 20 ° C. or more, when the processing temperature is adjusted to the high melting point side, The excessive heat applied to the low melting point caused fusion in the processing equipment.
Also, when the a1 and the b1 are different kinds of resins, the compatibility is poor due to the heat bonding between the different kinds, and as a result, the adhesion between the laminations is insufficient, and the separation between the laminations when the nonwoven fabrics are rubbed. A problem remained with the fuzz resistance. Furthermore, when the high melting point side and the low melting point side are set to different processing temperatures respectively,
The amount of heat applied to the middle layers, Layer 2 and Layer 3, is likely to be insufficient,
Peeling between the layers occurred.

[0008] The greatest effect for improving the fuzz resistance is to increase the bonding area ratio on the surface of the nonwoven fabric.
If the bonding area ratio is increased, the texture of the nonwoven fabric will be impaired. In addition, if the processing temperature is increased, not only fusion and wrapping around the thermocompression bonding rolls occur, but also damage to the fiber at the edge portion of the compression point increases, and the fiber is easily cut and fuzz resistance deteriorates. Further, since the compatibility between the laminations composed of different kinds of resins is generally poor, even at a relatively high processing temperature, the adhesiveness is poor and the fuzz resistance is poor. On the other hand, the bonding method that keeps the processing temperature low
Insufficient thermal bonding inside the nonwoven fabric causes insufficient strength of the nonwoven fabric and delamination. In other words, if the texture of the nonwoven fabric is emphasized, problems such as deterioration of fuzz resistance and delamination occur. Conversely, if emphasis is placed on the fuzz resistance, problems have arisen such as the texture of the nonwoven fabric and the deterioration of operability due to fusion or winding around the thermocompression bonding roll. As described above, various nonwoven fabric manufacturing methods that combine the texture of the nonwoven fabric and the adhesive strength between the nonwoven fabric laminates and fuzz resistance have been proposed.
Nonwoven fabrics with satisfactory performance have not been obtained.

[0009]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a composite nonwoven fabric having a texture of a nonwoven fabric, an adhesive strength between the nonwoven fabric lamination and a fuzz resistance, and a fiber product using the same.

[0010]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems. As a result, by adopting the following configuration, the expected purpose was expected to be achieved, and based on this finding, the present invention was completed. (1) A non-woven fiber aggregate (I) composed of a thermoplastic resin (A) having a base layer, at least one surface of which has a melting point higher by 2 to 17 ° C. than that of the thermoplastic resin (A), and A nonwoven fiber aggregate (II) comprising the same type of thermoplastic resin (A ') as (A) is laminated, and a nonwoven fiber aggregate (I)
And a nonwoven fiber aggregate (II), which is thermally bonded. (2) Thermoplastic resin (A) and thermoplastic resin (A ')
Independently of each other, low-density polyethylene, linear low-density polyethylene, high-density polyethylene, polypropylene, propylene-based terpolymer or propylene-based terpolymer, olefin-based resin, polyester, copolymer The composite nonwoven fabric according to the above (1), which is at least one member selected from the group consisting of polyester, nylon, and copolymerized nylon. (3) Nonwoven fiber aggregate (I) and nonwoven fiber aggregate (II)
Is composed of long fibers. The composite nonwoven fabric according to the above item (1) or (2), wherein (4) The composite nonwoven fabric according to any one of (1) to (3), wherein at least one selected from nonwoven fabrics, films, pulp sheets, knits, and woven fabrics other than the composite nonwoven fabric is used. Further laminated non-woven fabric. (5) An absorbent article using the composite nonwoven fabric according to any one of (1) to (3) or the laminated composite nonwoven fabric according to (4). (6) A wiper using the composite nonwoven fabric according to any one of (1) to (3) or the laminated composite nonwoven fabric according to (4).

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The composite nonwoven fabric of the present invention has a nonwoven fiber aggregate (I) made of a thermoplastic resin (A) as a base layer, and has a melting point higher than that of the thermoplastic resin (A) by 2 to 17 ° C on at least one surface thereof, Further, a nonwoven fiber aggregate (II) made of the same type of thermoplastic resin (A ′) as the thermoplastic resin (A) is laminated, and a nonwoven fiber aggregate (I) and a nonwoven fiber aggregate (II) are formed. Are thermally bonded. Since the thermoplastic resin (A) constituting the nonwoven fiber aggregate (I) and the thermoplastic resin (A ') constituting the nonwoven fiber aggregate (II) are the same type of resin, these laminates are: It has excellent compatibility of the melt at the time of heat melting and has good thermal adhesiveness. Therefore, since the nonwoven fiber aggregate (I) sufficiently adheres to the nonwoven fiber aggregate (II), a sufficient strength of the nonwoven fabric can be obtained, and at the same time, the degree of freedom of the fiber is suppressed. The texture of the nonwoven fabric is good because it also prevents peeling between the collective volume layers and is not excessively damaged by heat.

In the present invention, the combination of the thermoplastic resin (A) of the nonwoven fiber aggregate (I) and the thermoplastic resin (A ') of the nonwoven fiber aggregate (II) is the same as that of the thermoplastic resin (A). In comparison, the thermoplastic resin (A ') has a high melting point, a difference in melting point of 2 to 17 ° C, and is not particularly limited as long as it is the same type of resin. The same kind here means a homopolymer and various copolymers mainly composed of monomers constituting the homopolymer, and various copolymers mainly composed of a certain monomer and another copolymer mainly composed of the same monomer. Various copolymers with the comonomer, or
Various copolymers containing a certain type of monomer as a main component, various types of polymers containing the same monomer as a main component, and having different composition ratios from comonomers, polymers of different degrees of branching polymerized from the same monomer, between ester bonds or amide bonds. Are polymers having different bonding modes. Specific examples of the combination of thermoplastic resin (A) / thermoplastic resin (A ′) include high density polyethylene / low density polyethylene, linear low density polyethylene / high density polyethylene, linear low density polyethylene / low density Polyethylene, (binary copolymer or ternary copolymer of propylene and other α-olefin except ethylene or propylene) / (binary copolymer of propylene and other α-olefin except ethylene or propylene) Or terpolymer), polypropylene / (binary or terpolymer of propylene and other α-olefins other than ethylene or propylene), polyethylene terephthalate / polyethylene terephthalate copolymer, polyethylene terephthalate / Polybutylene terephthalate, 6,6 nylon / 6,6 nylon Polymer, 6,6 nylon / 6 nylon, 6,6 nylon /
Examples thereof include combinations of the same component resins having a melting point difference of 2 to 17 ° C. such as nylon 6, 10, and the like. Of these, 2
A combination of a propylene-based resin and a propylene-based resin having a melting point difference of １７17 ° C., a combination of a polyester-based resin and a polyester-based resin, and a combination of a polyamide-based resin and a polyamide-based resin are more preferably used.

As the polyethylene used for the thermoplastic resin (A) and the thermoplastic resin (A ') as an example of the present invention, polyethylene which is generally used industrially is preferably used. do it,
Low density polyethylene having a density of 0.910~0.925g / cm ^3, density linear low density polyethylene 0.926~0.940g / cm ^3, density of from 0.941 to 0.9
80 g / cm ³ of high density polyethylene. In particular, the melt flow rate (MI: JISK721)
0 is 2 to 10)
Polyethylene in the range of 0 g / 10 minutes is preferred.

In the present invention, the thermoplastic resin (A) and the thermoplastic resin (A ') are each independently a propylene homopolymer, a propylene binary random copolymer, or a propylene ternary random copolymer. Coalescence is also preferably used, and they are particularly suitable for melt flow rate (MF
R: JIS K7210 (measured in accordance with condition 14 in Table 1) is 2 to 150 g / 10 min, and the melting point is 120 to 150 g / min.
Preferably it is 165 ° C.

In the present invention, the propylene-based binary random copolymer and the propylene-based tertiary random copolymer used for the thermoplastic resin (A) and the thermoplastic resin (A ') are each independently propylene. And a small amount of ethylene or a small amount of 1-butene, 1-hexene, 1-octene, or 4,4′-
A crystalline random copolymer with an α-olefin such as dimethyl 1-pentene is preferred, and particularly, the MFR is 2 to 150 g.
A propylene-based binary random copolymer and a propylene-based ternary random copolymer having a melting point in the range of 120 to 158 ° C for / 10 minutes are suitably used. As a specific example, a propylene / ethylene binary random copolymer mainly composed of propylene containing 99.7 to 97.0 mol% of propylene units and 0.3 to 3.0 mol% of ethylene units, or 90% of propylene units Propylene / ethylene / polyethylene / polyethylene / polyethylene / ethylene / ethylene / ethylene / copolymer containing 0.4 to 95.0 mol%, 3.0 to 5.0 mol% of ethylene units, and 2.0 to 4.6 mol% of 1-butene units.
A ternary random copolymer of 1-butene is exemplified.

In the present invention, it is necessary that the melting point of the thermoplastic resin (A ') is higher by 2 to 17 ° C. than the melting point of the thermoplastic resin (A), and more preferably in the range of 5 ° C. to 17 ° C. And more preferably in the range of 8 ° C to 15 ° C. When this melting point difference greatly exceeds 17 ° C., there is difficulty in compatibility between the thermoplastic resin (A) and the thermoplastic resin (A ′),
A problem may occur in the fuzz resistance. On the other hand, if the temperature is lower than 2 ° C., the melting point of the single-layer nonwoven fabric is similar to the melting point of the single-layer nonwoven fabric. Due to the excessive amount of heat, it becomes a very hard non-woven fabric and the texture cannot be satisfied.

The thermoplastic resin (A) used in the present invention,
In addition to the thermoplastic resin (A '), other thermoplastic resins used in addition to these may further include an antioxidant, a light stabilizer, an ultraviolet absorber, and a neutralizing agent within a range that does not impair the effects of the present invention. A nucleating agent, an epoxy stabilizer, a lubricant, an antibacterial agent, a flame retardant, an antistatic agent, a pigment, a plasticizer, a hydrophilic agent, and the like may be appropriately added as necessary. Further, the nonwoven fabric of the present invention may be subjected to a treatment for attaching a surfactant or the like, if necessary.

The fiber composition of the nonwoven fiber aggregate (I) used in the composite nonwoven fabric of the present invention may be a single fiber of the thermoplastic resin (A), and the thermoplastic resin (A) may be partially or entirely exposed on the fiber surface. A composite fiber composed of the resin (A) and at least one other thermoplastic resin may be used. Specific examples of the cross-sectional shape of the conjugate fiber include a concentric sheath core type, a side-by-side type, an eccentric sheath core type, a multi-core type (sea-island type), a split type, and a variant type. In the above cross-sectional shape, in the case of a composite cross-sectional shape such as a concentric sheath core type or an eccentric sheath core type in which the thermoplastic resin of the core component is not exposed on the fiber surface, the thermoplastic resin used for the core component is a thermoplastic resin (A ), And more preferably 15 ° C. or higher than the thermoplastic resin (A). Further, in the above cross-sectional shape, in the case of a composite cross-sectional shape such as a parallel type, a split type,
Since the other thermoplastic resin may be exposed on the fiber surface, the other thermoplastic resin has a melting point higher than that of the thermoplastic resin (A) by 2 ° C. or more, and is the same as the thermoplastic resin (A). It is preferred that

The fiber composition of the non-woven fiber aggregate (II) used in the composite nonwoven fabric of the present invention may be a single fiber of a thermoplastic resin (A '), and the heat-exposed part or all of the fiber surface may be exposed. A composite fiber composed of the thermoplastic resin (A ′) and at least one other thermoplastic resin may be used. Specific examples of the cross-sectional shape of the conjugate fiber include a concentric sheath core type, a side-by-side type, an eccentric sheath core type, a multi-core type (sea-island type), a split type, and a variant type. In the cross-sectional shape, in the case of a composite cross-sectional shape such as a concentric sheath core type or an eccentric sheath core type in which the thermoplastic resin of the core component is not exposed on the fiber surface, the thermoplastic resin used for the core component is a thermoplastic resin (A ′). ) Is preferably 10 ° C. or higher than that of the thermoplastic resin (A ′).
It is more desirable to have a melting point higher by at least 0 ° C. Further, in the above-mentioned cross-sectional shape, in the case of a composite cross-sectional shape such as a parallel type or a split type, since other thermoplastic resin may be exposed on the fiber surface, the melting point is 2 times higher than that of the thermoplastic resin (A ′).
It is preferable that the temperature is higher by at least ° C and the same type as the thermoplastic resin (A ').

As a method of integrating the non-woven fiber aggregate (I) and the non-woven fiber aggregate (II), either a hot air heating method or a thermocompression processing method is possible. Thermocompression processing method is more preferably used. Since thermocompression bonding is a processing method using heat and pressure,
Compared to hot air heating processing, which is a processing method using hot air, bonding processing can be performed at a temperature lower than the melting point of the thermoplastic resin (low-melting resin) to be welded, and productivity is excellent, so that the cost is extremely excellent.

In the case where the nonwoven fiber aggregate is integrated by thermocompression bonding (embossing roll processing), the fuzz resistance is highly dependent on the emboss area ratio (convex portion) and the processing temperature. Therefore, in the composite nonwoven fabric of the present invention, the entire nonwoven fabric is a resin component of the same kind, and has excellent compatibility, so that at a processing temperature at which the surface of the nonwoven fabric is not damaged, the entire inside thereof sufficiently contributes to adhesion. To control the degree of freedom of the fiber. For this reason, compared with the conventional nonwoven fabric, the composite nonwoven fabric of the present invention is excellent in texture and fuzz resistance, and has sufficient nonwoven fabric strength when the embossed area ratio is the same.
Further, roll winding by the molten resin can be suppressed, and stable production (operability) can be performed. In the conventional nonwoven fabric processing, when the bonding area ratio is reduced, the degree of freedom of the fiber on the surface of the nonwoven fabric increases, while when the processing temperature is lowered, the degree of freedom of the fiber inside the nonwoven fabric increases, and both tend to decrease the fuzz resistance. Met.

The fibers constituting the nonwoven fiber aggregate (I) and the nonwoven fiber aggregate (II) used in the composite nonwoven fabric of the present invention are not particularly limited, and are each a single fiber or a composite fiber, or The fiber may be a single fiber or a combination of composite fibers, and various short fibers or long fibers may be used. For example, when using short fibers made of composite fibers as the fibers, as a method of manufacturing, using a spinneret plate having a composite fiber cross section of concentric sheath core type, eccentric sheath core type, etc., spinning by a known composite spinning method. After the obtained undrawn yarn is drawn by a drawing machine, the obtained drawn yarn is crimped by a crimper and cut into a desired cut length by a cutter to produce a short fiber.
In particular, as the composite cross-sectional shape, a concentric sheath-core type having excellent dimensional stability is preferable. Moreover, it can also be made into a chop by straight cutting without crimping after stretching. Also, a known melt-blowing production method in which a polymer stream melt-spun from a spinning machine is drawn and thinned by a high-pressure high-pressure air stream and collected and deposited on a moving collecting surface to form a web is illustrated. it can. In addition, the fiber obtained by the melt blow method is also mentioned as a representative of the short fiber.
On the other hand, when a long fiber made of a conjugate fiber is used as the fiber, as a manufacturing method, a spinneret plate having a cross section of a conjugate fiber such as a concentric sheath core type or an eccentric sheath core type is produced by a known spunbonding method. A method can be exemplified. In addition, by manufacturing long fibers by the spun bond method, the manufacturing process from fiber to web can be simplified as compared with the manufacturing of short fibers, so that a product can be manufactured at low cost and the texture of the obtained nonwoven fabric is good. Therefore, it is preferable to use long fibers in the present invention.

The fineness and basis weight of the fibers constituting the composite nonwoven fabric of the present invention are not particularly limited, but from 0.01 to 11 dtex and 5 to 4 dtex, respectively, in terms of texture and flexibility.
0 g / m ² is preferred, and more preferably 0.03 g / m ^2.
７7 dtex, 8 to 30 g / m ² . 5g / weight
If it is much lower than m ² , sufficient nonwoven fabric strength will not be obtained. Conversely, if it exceeds 40 g / m ² , sufficient nonwoven fabric strength will be obtained, but the feel will be poor. When the sheath-core type composite fiber is used, the composite weight ratio (wt% of sheath component / wt% of core component) is preferably in the range of 20/80 to 70/30, more preferably 40/60 to 60/30. 40. When the sheath component is less than 20% by weight, the heat adhesion of the obtained fiber becomes insufficient. On the other hand, when the sheath component exceeds 70%, the composite fiber shrinks during heat treatment, and the dimensional stability of the obtained fabric decreases. Tend to.

The basis ratio between the nonwoven fiber aggregate (I) and the nonwoven fiber aggregate (II) {the basis weight of the nonwoven fiber aggregate (I) / the basis weight of the nonwoven fiber aggregate (II)} is the same ratio. It is not limited to this, but can be arbitrarily selected, but since this is largely related to the physical properties of the obtained laminated nonwoven fabric, the basis weight ratio is 0.2 to 5
Preferably, Particularly preferably, it is 0.3 to 4. If the basis weight is significantly greater than 5, the adhesiveness of the non-woven fabric is reduced when heat-treated, and there is a difficulty in peeling between layers and fuzz resistance. If it is less than 0.2, the fuzz resistance is improved, but the texture of the nonwoven fabric may be impaired.

When the nonwoven fiber aggregate (I) and the nonwoven fiber aggregate (II) used in the present invention are integrated by thermocompression bonding,
Although there is no particular limitation on the manufacturing apparatus, a thermocompression bonding apparatus including a pair of emboss rolls and a flat roll is usually used. At this time, the pressure bonding temperature is determined by the melting point of the resin constituting the nonwoven fabric, but if there is a sufficient melting point difference between the nonwoven fiber aggregate (I) and the nonwoven fiber aggregate (II), peeling between the laminations is prevented. For this reason, it is desirable to set the roll temperature on the high melting point side higher between the two. Further, the emboss area ratio is preferably in the range of 5 to 30% with respect to the total area of the nonwoven fabric,
More preferably, it is 9 to 22%. The area of the fusion zone is 5
If it is less than 30%, delamination between nonwoven fabric laminations is a concern, and 30%
If it exceeds, the texture may be impaired.

In the composite nonwoven fabric of the present invention, other nonwoven fabrics, films, pulp sheets, knits, woven fabrics and the like can be laminated to the extent that the effect is not impaired, and a laminated composite nonwoven fabric can be obtained. When other nonwoven fabrics, films, pulp sheets, knits, woven fabrics, and the like are laminated, each may be laminated alone with the composite nonwoven fabric of the present invention, or may be laminated in combination with a plurality of nonwoven fabrics. The material is not limited and various materials can be used. However, it is preferable to include a material that can be bonded to the nonwoven fabric serving as the base layer, and it is more preferable that the material be a material that can be bonded.

The composite nonwoven fabric and laminated composite nonwoven fabric of the present invention can be used as a material for an absorbent article. In particular, it can be preferably used as a disposable diaper, napkin, sweat-absorbing pad, sebum-removing sheet material, and hand hygiene material for infants and adults. Further, the composite nonwoven fabric and the laminated composite nonwoven fabric of the present invention can be preferably used also as wipers. Examples include household disposable rags, window wipes, floor wipes, tatami wipes, and the like. In addition,
It can also be used as a disposable seat cover for airplanes and passenger vehicles, a toilet seat cover, a heat insulator for clothes, a base material for molding, and the like.

[0028]

The present invention will be described below in detail with reference to examples and comparative examples, but the present invention is not limited to these examples. The methods for measuring physical properties and the sensory evaluation in Examples and Comparative Examples are as follows.

(1) Melting point of thermoplastic resin (MP unit:
° C) Measured in accordance with JIS K 7122.

(2) Melt flow rate (unit: g / 1)
0 minutes) Each thermoplastic resin was measured according to the conditions of Table 1 of JIS K7210. The melt flow rate of a propylene-based polymer may be abbreviated as MFR. Further, the melt flow rate of the ethylene polymer may be abbreviated as MI.

(3) Hand feeling of non-woven fabric A sensory test was conducted by 10 panelists, and when 8 or more persons judged soft, it was excellent, and when 6 to 7 persons judged soft, good, 5 persons or more Was judged to be unacceptable when it was judged that the sample lacked a soft feeling.

(4) Nonwoven Fabric Strength (MD Direction) A test piece was cut out from the nonwoven fabric in the following size by setting the machine direction of the nonwoven fabric to the machine direction and the direction perpendicular to the machine direction to the CD direction. 15cm × MD direction from non-woven fabric
Five strips of 2.5 cm in the CD direction were cut out to obtain samples for measuring the strength of the nonwoven fabric. The strength of this test piece was measured using an Autograph AGS500D manufactured by Shimadzu Corporation under the conditions of a gripping interval of 10 cm and a pulling speed of 10 cm / min, and the maximum strength (N / 2.5 cm) was determined. The measurement was performed once per sheet, and a total of five measurements were performed, and the average value was calculated. The average value was taken as the value of the nonwoven fabric strength of the sample.

(5) Evaluation of Fuzzing Resistance The following describes a method for evaluating the fuzzing resistance (the difficulty of fluffing) of the obtained nonwoven fabric. The evaluation method conforms to JIS L0849-1974. As the test piece, the non-woven fabric to be evaluated was 4 cm in the MD direction.
X Cut into a size of 20 cm in the CD direction, and four pieces are prepared. Furthermore, the nonwoven fabric to be evaluated is placed in the MD direction at 20 cm × C
It is cut into a size of 4 cm in the D direction, and four pieces are prepared. 3.5cm in width at the center in the longitudinal direction of the nonwoven fabric sample
Attach a 20cm long double-sided tape. At this time, MD
-For each CD, prepare two nonwoven fabric samples on the embossed roll treated surface side and the flat roll treated surface side. A nonwoven fabric sample was stuck on a sample table of a friction tester (manufactured by Suga Test Instruments Co., Ltd.), and Kanakin No. 3 cloth (4 cm × 5
cm). The friction element is placed on the nonwoven fabric sample, and the friction test is performed 150 times reciprocally. At this time, the degree of rubbing (the generation of pills and the fluffiness) of the nonwoven fabric surface is sensorially evaluated based on the following criteria (sensory index). Judgment criteria (sensory index) ：: Neither fluff nor fluff is observed. ：: Some fluffing is observed. Δ: Many fluffs and pills are observed. X: Many fluffs and multiple pills are observed.

Example 1 The nonwoven fiber aggregate (I) had a melting point of 147 ° C.
FR is 38 g / 10 min, and ethylene unit is 3.1 m
ol%, a propylene-based binary random copolymer containing 96.9 mol% of propylene units as a thermoplastic resin (A) as a sheath component, having a melting point of 160 ° C. and an MFR of 36 g /
Using crystalline polypropylene which is 10 minutes as a core component,
Spinning was performed by a known spunbonding method to produce a nonwoven fiber aggregate (I). As a specific production method, both were charged into a spinning machine from separate hoppers, melted by heat, and discharged as a group of composite filaments from a sheath-core composite spinneret.
Next, by letting this pass through air soccer,
The long fiber was drawn and drawn into a 2.3 dtex composite long fiber. Further, after the discharged long fiber group is charged by a charging device, the fiber is opened by colliding with a reflecting plate, collected on an endless net-shaped conveyor provided with a suction device on the back surface, and a composite long fiber web is formed. Obtained. This web was used as a nonwoven fiber aggregate (I). Similarly, thermoplastic resin (A ')
Was spun by a spun bond method using crystalline polypropylene having a melting point of 160 ° C. and an MFR of 36 g / 10 minutes to obtain a web composed of a single filament of 2.0 dtex. This web was used as a nonwoven fiber aggregate (II). The non-woven fiber aggregate (I) is used as a base layer, and the non-woven fiber aggregate (II) is deposited so as to be located in upper and lower layers.
The composite nonwoven fabric was obtained by thermocompression bonding using an embossing thermocompression bonding apparatus of 0 N / mm, a compression bonding area ratio of 15%, and a heat treatment temperature of embossing roll / flat roll = 145/145 ° C. As can be seen in Table 1, the obtained composite nonwoven fabric has a texture,
The nonwoven fabric was strong and had excellent fuzz resistance.

Example 2 For the non-woven fiber aggregate (I), polybutylene terephthalate having a melting point of 240 ° C. and an intrinsic viscosity of 0.65 was used as the sheath resin as the thermoplastic resin (A), and the melting point was 255.
A polyethylene terephthalate having an intrinsic viscosity of 0.63 ° C. was used as a core component and spinning was performed by a known melt spinning method. First, both are put into a spinning machine from separate hoppers, are thermally melted, and are discharged as a composite fiber group from a sheath-core type composite spinneret, and the single yarn fineness is 6.0 dtex.
Undrawn yarn. Subsequently, the undrawn yarn was drawn 2.4 times with a hot roll, mechanically crimped, and further cut to obtain a composite fiber of 2.5 dtex × 38 mm. The obtained composite fiber was carded by a roller card machine to obtain a web. This was used as a nonwoven fiber aggregate (I). Similarly, for the nonwoven fiber aggregate (II),
Using a polyethylene terephthalate having a melting point of 255 ° C. and an intrinsic viscosity of 0.63 as the thermoplastic resin (A ′), spinning was performed by a known melt spinning method to produce a nonwoven fiber aggregate (II). First, the polyethylene terephthalate was charged into a spinning machine, melted by heat, and discharged as a single fiber group from a spinneret to obtain an undrawn yarn having a single yarn fineness of 6.0 dtex. Subsequently, the undrawn yarn was drawn 2.4 times with a hot roll, mechanically crimped, and further cut to obtain a single fiber of 2.5 dtex × 38 mm. The obtained single fiber was carded by a roller card machine to obtain a web. This was used as a nonwoven fiber aggregate (II). The nonwoven fiber aggregate (I) is deposited on the base layer, and the nonwoven fiber aggregate (II) is deposited on one surface (upper layer) of the nonwoven fiber aggregate (I). / Flat roll = 225/210 ° C., using an embossing thermocompression bonding apparatus to obtain a non-woven fabric. As shown in Table 1, the obtained composite nonwoven fabric was excellent in both texture, nonwoven fabric strength, and fuzz resistance.

Example 3 The nonwoven fiber aggregate (I) was produced by spinning using the same thermoplastic resin (A) and other thermoplastic resin as in Example 1 by a known melt blow method. did. First, put both into the spinning machine from separate hoppers,
It was melted by heat and discharged as a composite fiber group from a sheath-core composite spinneret. Next, this was made fine by blowing with high-pressure hot air, and collected as a composite short fiber web on an endless net-shaped conveyor. This was used as a nonwoven fiber aggregate (I). The nonwoven fiber aggregate (I) is used as a base layer, and the nonwoven fiber aggregate (II) collected in Example 1 is deposited on the upper and lower layers so that the linear pressure is 60 N / mm.
A thermocompression bonding process was performed using an embossing thermocompression bonding apparatus with a compression bonding area ratio of 15% and a heat treatment temperature of embossing roll / flat roll = 145/145 ° C. to obtain a composite nonwoven fabric. As can be seen in Table 1, the obtained composite nonwoven fabric has a texture, strong nonwoven fabric,
The fuzz resistance was very good.

Example 4 The nonwoven fiber aggregate (I) had a melting point of 125 ° C.
I is 20 g / 10 min, and linear low-density polyethylene is used as the sheath component as the thermoplastic resin (A), and the melting point is 161.
A crystalline polypropylene having an MFR of 40 g / 10 minutes at a temperature of 40 ° C. was used as a core component and spinning was performed by a known spunbonding method. First, both were put into a spinning machine from separate hoppers, thermally melted, and discharged as a composite fiber group from a sheath-core composite spinneret. Next, this is passed through an air soccer and discharged to draw and stretch.
A sheath-core type composite long fiber of 0 dtex was obtained. Further, after the discharged long fiber group is charged by a charging device, the fiber is opened by colliding with a reflecting plate, collected on an endless net-shaped conveyor provided with a suction device on the back surface, and a composite long fiber web is formed. Obtained. This was used as a nonwoven fiber aggregate (I). Furthermore,
A high-density polyethylene having a melting point of 131 ° C. and an MI of 35 g / 10 minutes is used as a sheath component as a thermoplastic resin (A ′), and crystalline polypropylene having a melting point of 161 ° C. and an MFR of 40 g / 10 minutes is used as a core component. A 2.0 dtex sheath-core composite continuous fiber web was obtained in a similar manner by a known spunbonding method, and this was used as a nonwoven fiber aggregate (II). The nonwoven fiber aggregate (I) is used as a base layer, and the nonwoven fiber aggregate (II) is deposited so as to be located on one side (lower layer) of the nonwoven fiber aggregate (II). / Flat roll = 105/110 ° C
By thermocompression bonding using an embossing thermocompression bonding apparatus. As can be seen from Table 1, the obtained composite nonwoven fabric was very excellent in fuzz resistance, and both the texture and the strength of the nonwoven fabric were excellent.

Example 5 The nonwoven fiber aggregate (I) had a melting point of 143 ° C.
FR is 41 g / 10 minutes, and ethylene unit is 3.1 m
ol%, a propylene-based tertiary random copolymer containing 1.3 mol% of 1-butene unit and 95.6 mol% of propylene unit as a sheath component as a thermoplastic resin (A),
Using a crystalline polypropylene having a melting point of 160 ° C. and an MFR of 36 g / 10 min as a core component, spinning was performed by a known melt spinning method. First, both were put into a spinning machine from separate hoppers, melted by heat, and discharged as a group of composite fibers from a sheath-core type composite spinneret to obtain an undrawn yarn having a single yarn fineness of 6.0 dtex. Subsequently, the undrawn yarn is drawn 2.4 times with a hot roll, and mechanical crimping is applied.
Further cutting was performed to obtain a composite fiber of 2.5 dtex × 38 mm. The obtained composite fiber was carded by a roller card machine to obtain a web. This was used as a nonwoven fiber aggregate (I). Similarly, melting point is 160 ° C, M
Using a crystalline polypropylene having an FR of 36 g / 10 min as the thermoplastic resin (A ′), spinning was performed by a known melt spinning method to produce a nonwoven fiber aggregate (II). First, the polypropylene is put into a spinning machine and melted by heat,
5. A single fiber group is discharged from the spinneret as a single fiber group.
An undrawn yarn of 0 dtex was used. Subsequently, the undrawn yarn was drawn 2.4 times with a hot roll, mechanically crimped, and further cut to obtain a single fiber of 2.5 dtex × 38 mm. The obtained single fiber was carded by a roller card machine to obtain a web. This was used as a nonwoven fiber aggregate (II). The non-woven fiber aggregate (II) is positioned on the upper and lower layers based on the non-woven fiber aggregate (I).
And a linear pressure of 60 N / mm, a compression bonding area ratio of 15%, and a heat treatment temperature of embossing roll / flat roll = 145/1.
A thermocompression treatment was performed by a 45 ° C. emboss thermocompression bonding apparatus to obtain a nonwoven fabric. As shown in Table 1, the obtained composite nonwoven fabric was excellent in both texture, nonwoven fabric strength, and fuzz resistance.

Example 6 A back sheet of a commercially available disposable diaper for infants (M size) was peeled off, and the composite nonwoven fabric of the present invention obtained in Example 3 was replaced with a polyethylene film of a diaper by hot melt instead of the back sheet. And used as a back sheet. The obtained absorbent article (disposable diaper for babies and infants) had a fluffing resistance of ◎ and an excellent tactile sensation.

Example 7 The composite nonwoven fabric of the present invention obtained in Example 1 and a natural pulp web were entangled with a high-speed columnar water stream at a pressure of 294 N / m ² to obtain a laminated composite nonwoven fabric having a basis weight of 60 g / m ^2. When it was used as a window blowing wiper, it showed very good dust adsorbing properties.

Comparative Example 1 Using polyethylene terephthalate having a melting point of 255 ° C. and an intrinsic viscosity of 0.63, spinning was carried out by a known melt spinning method in the same manner as in the nonwoven fiber aggregate (II) of Example 2.
A nonwoven fiber aggregate (I) was produced. First, this polyethylene terephthalate is charged into a spinning machine, melted by heat, discharged from a spinneret as a single fiber group, and has a single yarn fineness of 6.0.
The dtex undrawn yarn was used. Subsequently, the undrawn yarn was drawn 2.4 times with a hot roll, mechanically crimped, and further cut to obtain a single fiber of 2.5 dtex × 38 mm. The obtained single fiber was carded by a roller card machine to obtain a web. This was used for the base layer as a nonwoven fiber aggregate (I). Non-woven fiber aggregate (II)
For the core component, a linear low-density polyethylene having a melting point of 125 ° C. and an MI of 20 g / 10 min was used as a sheath component, and a polyethylene terephthalate having a melting point of 255 ° C. and an intrinsic viscosity of 0.63 was used as a core component. Spinning was performed by a known melt spinning method to produce a nonwoven fiber aggregate (II). First, put both into the spinning machine from separate hoppers,
It was melted by heating and discharged from a sheath-core type composite spinneret as a composite fiber group to obtain an undrawn yarn having a single yarn fineness of 8.0 dtex. Subsequently, the undrawn yarn was drawn 4.2 times with a hot roll, mechanically crimped, and further cut to obtain 1.9.
The composite fiber was dtex × 38 mm. The obtained composite fiber was carded with a roller card machine to obtain a web. This was used as a nonwoven fiber aggregate (II). Further, a nonwoven fiber aggregate (I) and a web of the nonwoven fiber aggregate (II) mixed at 50/50 (mixed fiber) were used as a nonwoven fiber aggregate (III). Non-woven fiber aggregate of base layer (I)
The nonwoven fiber aggregate (III) layer is placed between the laminate of the nonwoven fiber aggregate (II) and the lower layer, and the linear pressure is 60 N / mm, the compression area ratio is 15%, and the heat treatment temperature is embossed roll / flat roll = 225. The composite nonwoven fabric was manufactured by processing with an embossing thermocompression bonding device at / 105 ° C. The resulting nonwoven fabric was poor in overall adhesion, very poor in fuzz resistance, and exhibited a low value of nonwoven fabric strength.

Comparative Example 2 As the nonwoven fiber aggregate (I), the nonwoven fiber aggregate (I) collected in Comparative Example 1 was used. As the nonwoven fiber aggregate (II), the nonwoven fiber aggregate (II) collected in Comparative Example 1 was used. Further, the weight ratio of the nonwoven fiber aggregate (I) and the nonwoven fiber aggregate (II) per unit volume of the web is 75/25.
The non-woven fiber aggregate mixed (mixed) was used as the non-woven fiber aggregate (III). Similarly, the nonwoven fiber aggregate (I)
A nonwoven fiber aggregate (mixed fiber) having a weight ratio per unit volume of the web of the nonwoven fiber aggregate (II) of 25 and 75 was used as a nonwoven fiber aggregate (IV). Between the nonwoven fiber aggregate of the base layer (I) and the nonwoven fiber aggregate of the lower layer (II),
From the base layer side, the nonwoven fiber aggregate (III) and the nonwoven fiber aggregate (I
V), the linear pressure is 60 N / mm, the crimping area ratio is 15
%, Heat treatment temperature emboss roll / flat roll = 22
The composite nonwoven fabric was obtained by thermocompression treatment using an embossing thermocompression device at 5/105 ° C. The resulting nonwoven fabric was poor in overall adhesion, had very poor fuzz resistance, and exhibited a low value of nonwoven fabric strength.

Comparative Example 3 The nonwoven fiber aggregate (I) collected in Example 1 was used as the nonwoven fiber aggregate (I). For the nonwoven fiber aggregate (II), high-density polyethylene having a melting point of 131 ° C. and an MI of 35 g / 10 minutes was used as a sheath component, and the melting point was 160.
It was manufactured by spinning according to a known spunbond method using a crystalline polypropylene having an MFR of 36 g / 10 min at ℃ as a core component. First, both were put into a spinning machine from separate hoppers, thermally melted, and discharged as a composite fiber group from a sheath-core composite spinneret. Next, this is passed through air soccer and discharged to draw and stretch,
A 2.0 dtex sheath-core composite long fiber was obtained. Further, after the discharged long fiber group is charged by a charging device, the fiber is opened by colliding with a reflecting plate, collected on an endless net-shaped conveyor provided with a suction device on the back surface, and a composite long fiber web is formed. Obtained. This was used as a nonwoven fiber aggregate (II). The nonwoven fiber aggregate (I) is used as a base layer, and the nonwoven fiber aggregate (II) is deposited so as to be positioned above and below the base layer.
/ Mm, a compression bonding area ratio of 15%, a heat treatment temperature embossing roll / flat roll = 110/110 ° C. As shown in Table 2, the obtained composite nonwoven fabric was composed of different kinds of resins and had no compatibility, and thus had poor adhesiveness and poor fuzz resistance.

Comparative Example 4 Using the composite nonwoven fabric obtained in Comparative Example 3, a linear pressure of 60 N /
mm, crimping area ratio 15%, heat treatment temperature embossing roll /
A thermocompression bonding process was performed with an embossing thermocompression bonding apparatus with a flat roll of 130/130 ° C. to obtain a composite nonwoven fabric. At this time, the fused resin was found on the thermocompression bonding roll. Also,
The texture of the obtained nonwoven fabric was poor, and as a result, the texture (soft feeling) tended to be very poor as shown in Table 2.

Comparative Example 5 The nonwoven fiber aggregate (II) collected in Comparative Example 1 was used as the nonwoven fiber aggregate (I). As the nonwoven fiber aggregate (II), the nonwoven fiber aggregate (I) collected in Comparative Example 1 was used. The non-woven fiber aggregate (I) is used as a base layer, and the non-woven fiber aggregate (II) is deposited so as to be positioned on the upper layer. The linear pressure is 60 N / mm, the compression area ratio is 15%, and the heat treatment temperature is embossed roll / flat. A thermocompression treatment was carried out using an emboss thermocompression bonding machine at a roll of 225/105 ° C. to obtain a nonwoven fabric. As can be seen from Table 2, the obtained composite nonwoven fabric had poor compatibility due to lack of compatibility and was inferior in fuzz resistance.

From the Examples and Comparative Examples, the composite nonwoven fabric of the present invention has a nonwoven fiber aggregate (I) composed of a thermoplastic resin (A) as a base layer, and at least one surface thereof is provided with the thermoplastic resin (A). A nonwoven fiber aggregate (II) comprising a thermoplastic resin (A ') of the same type as the thermoplastic resin (A') having a melting point higher than that of the thermoplastic resin (A) by 2 to 17 ° C. It has been found that the layers can be sufficiently adhered to each other by performing the heat treatment at a temperature substantially equal to or near the softening temperature of each of the thermoplastic resin (A) and the thermoplastic resin (A ′). In addition, from the above, the composite nonwoven fabric has sufficient nonwoven fabric strength, not only does not cause problems such as delamination and fluffing, but also does not apply excessive heat, and thus has a satisfactory texture. Met. Further, when the composite nonwoven fabric was used for a top sheet and a back sheet of disposable diapers for babies and infants, a fiber product having satisfactory fuzz resistance and excellent tactile sensation was obtained.

[0047]

[Table 1]

[0048]

[Table 2]

[0049]

The composite nonwoven fabric of the present invention has a very soft and good texture. The composite nonwoven fabric and the laminated composite nonwoven fabric of the present invention are further used as fiber products such as absorbent articles and wipers because each layer is excellent in fuzz resistance without delamination and has sufficient nonwoven fabric strength in practical use. High value.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) A61F 13/511 B32B 5/26 13/15 A47L 1/15 13/514 A61F 13/18 310 B32B 5/26 320 // A61F 13/49 A41B 13/02 E A47L 1/15 F term (reference) 3B029 BB02 BB07 3B074 AA02 AA08 AB01 AC03 BB04 4C003 BA02 BA08 CA01 CA05 CA06 4F100 AK01A AK01B AK03A AK03B07 AK05B07 AK05BAK AK05B AK41B AK41J AK42 AK48A AK48B AK48J AK62A AK62B AK63A AK63B AK64 AK66A AK66B AK80A AK80B AL01A AL01B AT00C BA02 BA03 BA07 BA10A BA10C BA13 BA26 DG02C DG04A DG04B DG12C DG13C DG15A DG15B DG15C EJ19 EJ40 EJ42 GB72 JA04A JA04B JD14 JK06 JK13 4L047 AA14 AA21 AA23 AA27 AA28 AB02 AB03 BA09 BB09 CA05 CB01 CB10 CC03 CC04 CC05 CC16

Claims (6)

[Claims] 1. A non-woven fiber aggregate (I) comprising a thermoplastic resin (A) having a base layer having at least one surface having a melting point higher than that of the thermoplastic resin (A) by 2 to 17 ° C. A nonwoven fiber aggregate (II) made of the same type of thermoplastic resin (A ′) as the thermoplastic resin (A) is laminated, and the nonwoven fiber aggregate (I) and the nonwoven fiber aggregate (II) are thermally bonded. A composite nonwoven fabric characterized by being made. 2. The thermoplastic resin (A) and the thermoplastic resin (A ′) are each independently a low-density polyethylene,
A group consisting of linear low-density polyethylene, high-density polyethylene, polypropylene, propylene-based terpolymers, or propylene-based terpolymers such as olefinic resins, polyesters, copolyesters, nylons, and copolymerized nylons The composite nonwoven fabric according to claim 1, wherein the composite nonwoven fabric is at least one member selected from the group consisting of: 3. The nonwoven fiber aggregate (I) and the nonwoven fiber aggregate (II) are composed of long fibers.
Or the composite nonwoven fabric according to claim 2. 4. The composite nonwoven fabric according to any one of claims 1 to 3, further comprising at least one selected from nonwoven fabrics, films, pulp sheets, knits, and woven fabrics other than the composite nonwoven fabric. Laminated composite nonwoven fabric. 5. An absorbent article using the composite nonwoven fabric according to claim 1 or the laminated composite nonwoven fabric according to claim 4. 6. A wiper using the composite nonwoven fabric according to claim 1 or the laminated composite nonwoven fabric according to claim 4.