JP2001303444A - Highly water-absorbing fiber, nonwoven fabric using the same, nonwoven fabric laminate and absorptive article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fiber prevented from the highly water-absorbing resin's movement and coming off the fiber and sufficiently manifesting the water absorbency of the resin without deteriorating resin performance, and to provide a nonwoven fabric using such fibers. SOLUTION: This highly water-absorbing fiber comprises thermoplastic fibers and a highly water-absorbing resin; wherein the resin is embedded in the thermoplastic fibers and part of the resin is exposed onto the surface of the fibers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a highly water-absorbent resin (hereinafter, abbreviated as SAP), which can be easily retained.
The present invention relates to a highly water-absorbent fiber which prevents migration and falling of the water and stably expresses the absorption performance of SAP, and a nonwoven fabric using the same. More specifically, the present invention relates to a superabsorbent fiber used for a water-absorbent article that requires water absorbency, such as a disposable diaper, sanitary napkin, pad for incontinence, pad for breast milk, wiper, and filter.

[0002]

2. Description of the Related Art At present, absorbent articles using a mixture of SAP having high water absorption performance and pulp having an excellent initial water absorption rate are used. However, when pulp is mixed, there is a problem such as an increase in volume when storing or carrying in the water-absorbent article, and it is desired to reduce the mixing ratio of the pulp or to make the pulp unused. In that case, the property of retaining the SAP in the fiber aggregate instead of the pulp is required. Conventionally, even when pulp is used in combination with a water absorbent article,
It is difficult to retain the AP, and often the SAP is partially biased, causing gel blocking and the like, and often reducing the water absorption of the SAP. As a specific example, the above-described tendency was well exhibited in the SAP used in the absorbent portion of the disposable diaper. As a remedy, SAP migration is prevented by using a binder component or utilizing SAP's swellability. In that case, SAP
Although the effect of preventing the movement and dropping of water becomes high, the level of achieving both SAP retention and water absorption, such as a decrease in water absorption performance, is not yet at a satisfactory level. For this reason, SAP
There has been a demand for a water-absorbing article that prevents falling off and has high water absorption.

[0003]

SUMMARY OF THE INVENTION The object of the present invention is to
An object of the present invention is to provide a fiber and a non-woven fabric using the fiber, which prevent migration of P and fall off and reduce the performance of the highly water-absorbent resin and sufficiently exhibit water absorption.

[0004] The present inventors have conducted intensive studies to achieve the above object, and as a result, SAP was buried in the fiber by utilizing the softening and the fluidity of the thermoplastic fiber at the time of melting.
And by exposing a part of it to the fiber surface,
The SAP retention in the fiber is improved to prevent the SAP from falling off, and as a result, the resulting superabsorbent fiber aggregate (hereinafter abbreviated as SAP fiber aggregate) can reduce the water absorption of SAP. In addition, the inventors have learned that the water absorption performance inherent in SAP can be exhibited, and have completed the present invention.

[0005]

The present invention has the following arrangement to solve the above-mentioned problems. (1) A superabsorbent fiber comprising a thermoplastic fiber and a superabsorbent resin, wherein the superabsorbent resin is embedded in the thermoplastic fiber and a part thereof is exposed on the fiber surface. Super absorbent fiber. (2) The superabsorbent fiber according to the above (1), wherein the thermoplastic fiber is a thermoplastic conjugate fiber composed of two or more resins having different melting points. (3) The superabsorbent fiber according to the above (1) or (2), wherein the relationship between the diameter (X) of the thermoplastic fiber and the average particle size (Y) of the superabsorbent resin is X> Y. (4) The superabsorbent fiber according to any one of the above (1) to (3), wherein the form of the superabsorbent fiber is a nonwoven fiber aggregate. (5) The superabsorbent fiber according to any one of the above (1) to (3), wherein the form of the superabsorbent fiber is a nonwoven fiber aggregate obtained by an airlaid method. (6) A nonwoven fabric containing the superabsorbent fibers according to any one of the above (1) to (5). (7) A nonwoven fabric obtained by heat-treating the superabsorbent fiber according to any one of the above (1) to (5). (8) A nonwoven fabric laminate obtained by laminating the nonwoven fabric according to the above (6) or (7) and another sheet. (9) The nonwoven fabric laminate according to the above (8), wherein the other sheet is at least one of a nonwoven fabric, a film, a knit, and a woven fabric. (10) An absorbent article using the fiber according to any one of (1) to (5). (11) An absorbent article using the nonwoven fabric according to the above (6) or (7). (12) An absorbent article using the nonwoven fabric laminate according to the above (8) or (9).

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The thermoplastic fibers used in the superabsorbent fibers of the present invention include, for example, polypropylene, high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and a crystalline copolymer of propylene and α-olefin. Polyolefins, polyamides, polyethylene terephthalate, polybutylene terephthalate, low-melting polyesters obtained by copolymerizing diols with terephthalic acid / isophthalic acid, polyesters such as polyester elastomers, fluororesins, mixtures of the above resins, and other heat that can be spun. A plastic resin can be used and is not particularly limited.

The thermoplastic resin used in the present invention further includes an antioxidant, a light stabilizer, an ultraviolet absorber, a neutralizer, a nucleating agent, and an epoxy stabilizer as long as the effects of the present invention are not impaired. If necessary, additives such as a lubricant, an antibacterial agent, a flame retardant, an antistatic agent, a pigment, and a plasticizer may be added.

[0008] The cross-sectional shape of the thermoplastic fiber used in the present invention is not particularly limited, and may be any of a perfect circle, an ellipse, and an irregular shape (triangle, Yaba, etc.). The relationship between the diameter (X) of the thermoplastic fiber and the SAP average particle diameter (Y) is more important than the cross-sectional shape. The relationship between X and Y is preferably X> Y, and more preferably 2X> Y. If the value of Y is too large as compared to the value of X, damage to the fiber will increase, fiber strength will decrease, and further, exposure from the fiber will increase too much, and the SAP retention will decrease.

The form of the thermoplastic fiber used in the present invention is not particularly limited, and any of a regular fiber and a conjugate fiber can be used. The use of a conjugate fiber is a particularly preferred embodiment of the present invention. By using the composite type, the strength of the nonwoven fabric can be increased due to the presence of the core component. If the thermoplastic fiber is a composite type,
It is formed of a low-melting resin and a high-melting resin, but the composite ratio is not particularly limited.
The AP retention is improved, and as the core component increases, the fiber strength tends to increase. The form of the composite may be a parallel type, a sheath-core type, an eccentric sheath-core type, a multilayer composite type, or the like, as long as the low-melting-point resin forms at least a part of the fiber surface, and more preferably a low-melting-point resin. It is desirable that the resin be formed continuously on the fiber surface. The form of the above-mentioned thermoplastic fiber can be properly used depending on the application.

The thermoplastic fiber used in the present invention can be spun by a commonly used melt spinning machine using a die having an arbitrary shape. The discharge amount and the take-up speed are arbitrarily set, and the undrawn yarn is about 1 to 5 times the target fineness.
At this time, it is preferable to spin at as high a temperature as possible in order to make the SAP easily buried.

Next, in the stretching step, the unstretched yarn obtained in the spinning step is performed at a temperature lower than the melting point of the resin constituting the unstretched yarn under an arbitrary stretching ratio. As an example, 40-1
Using a heated roll heated to 20 ° C., the speed ratio between the rolls is set between 1: 2 and 1: 5. At that time, it is preferable to perform stretching at a high stretching temperature and a low stretching ratio in order to easily bury the SAP.

The number of crimps, fineness, and fiber length of the thermoplastic fiber used in the present invention are not particularly limited. It is desirable that these adjustments be appropriately performed when processing the nonwoven fabric. Further, the SAP used in the present invention has a three-dimensional structure obtained by crosslinking an ionic water-soluble polymer, and can absorb various liquid substances. Such SAPs are generally starch-based and acrylic-based, and have a water absorption capacity of 100 to 1000 g / g.
It is used in various industrial fields such as food, civil engineering, architecture, medical, electricity, paint, and sanitary materials.

The superabsorbent fiber of the present invention is prepared by bringing the thermoplastic fiber obtained in the above step into contact with the SAP and heat-treating the thermoplastic fiber at a temperature not lower than the softening point temperature of the fiber surface. Obtained by being buried.

The method for producing the superabsorbent fiber of the present invention is not particularly limited, but the preferred method is as follows. First, the thermoplastic fiber obtained under the above conditions is formed into a fiber aggregate in the form of a tow which is bundled in a filament state, or is cut to an arbitrary length, specifically, a length of 3 mm to 150 mm, and A fiber aggregate such as a web is formed by a processing method such as a ding method, an air laid method, or a needle punch method (the tow-like or web-like fiber aggregate is referred to as a nonwoven fiber aggregate). When the thermoplastic fibers are made into a non-woven fiber aggregate or after being made into a non-woven fiber aggregate, the SAP is mixed or laminated so as to uniformly contact the non-woven fiber aggregate and subjected to heat treatment. Thus, the SAP is partially embedded in the thermoplastic fiber to obtain the superabsorbent fiber of the present invention as an SAP nonwoven fiber aggregate. Also, before the thermoplastic fiber is made into a nonwoven fiber aggregate, such as after the drawing step, mixing of the SAP is performed, and then a heat treatment is performed to partially bury the SAP in the thermoplastic fiber, There is no problem as a non-woven fiber aggregate.

The nonwoven fabric of the present invention can be produced by subjecting the nonwoven fiber aggregate obtained under the above conditions to a heat treatment with a hot air drier, a calender roll or the like.
The heat treatment is performed under general conditions according to the basis weight, the heat treatment method, the melting point of the thermoplastic fiber, the fineness, and the like. In addition, a nonwoven fabric can also be obtained by using a spunbond method or a melt blow method, in which a nonwoven fabric is directly formed as long fibers. In that case,
It is preferable that the SAP is brought into contact with the non-woven fabric before the heat treatment, but there is no problem if the SAP is buried in the thermoplastic fiber with a part thereof exposed on the surface after the non-woven fabric.

The SAP fiber aggregate or nonwoven fabric of the present invention can be obtained under the above conditions. The present invention does not impede mixing other fibers such as pulp and rayon at all, and may be appropriately mixed as needed.

As a method for obtaining the nonwoven fiber aggregate or nonwoven fabric of the present invention, an airlaid method is particularly preferred. Compared to other methods, the air-laid method uses SAP-bearing fibers and S
Because SAP is technically easy to mix, SAP in non-woven fabric
Is not easily developed, and it is easy to uniformly disperse it throughout the inside of the nonwoven fabric, and a nonwoven fabric having a good texture without unevenness in water absorption can be easily obtained.

The airlaid method is a method for obtaining a web using short fibers. An example procedure is shown below. First,
The thermoplastic fibers used in the present invention or the thermoplastic fibers in a state in which the SAPs are buried are cut into short fibers into short fibers, and the short fibers are fed into a fiber opening machine, mechanically opened, and sent to a cotton feeding circulation duct. At that time, there is no problem if other fibers are simultaneously put into the cotton feeding circulation duct. Further, in this step, SA
P can be mixed and sent to a cotton feed circulation duct. Various fibers are mixed in the cotton circulation duct and passed through an air laid machine to form a nonwoven fiber aggregate. Also,
After forming the non-woven fiber aggregate, it is also possible to further laminate SAP and other fibers on the non-woven fiber aggregate. There are various types of air laid machines, but a typical one is to disperse and drop mixed fibrous material from a drum-shaped screen portion, suck with a suction device, laminate, and form a web-shaped non-woven fabric. A woven fiber aggregate can be exemplified. The screen part referred to here, for example, vibrates a box-shaped sieve back and forth, left and right, up and down, horizontally circular or the like,
A type in which short fibers are dispersed and dropped from the mesh of a sieve, or a net-shaped metal perforated plate having holes in the shape of a circle or a square is formed into a cylindrical shape and has a fiber inlet on its side surface, There is a net-like cylindrical type in which fibers are dispersed and dropped from the eyes.

Since the nonwoven fiber aggregate or nonwoven fabric of the present invention produced by the airlaid method uses short fibers having extremely short fiber lengths, each fiber or the like is randomly dispersed and arranged in different directions. It is laminated. Therefore, the SAP is buried in the thermoplastic fiber inside the nonwoven fabric and is evenly dispersed even when a part of the SAP is exposed on the fiber surface, and the bonding state between the short fibers or between the thermoplastic fiber and the SAP is uniform and excellent. In addition, since the inside of the nonwoven fabric has a matrix structure that is extremely suitable for water permeability, the SAP after water absorption and expansion is retained in the matrix structure of the nonwoven fabric without impairing the water absorption of the SAP. Of the non-woven fabric, and also prevents a decrease in water absorption of the non-woven fabric. Further, the strength of the nonwoven fabric is not deviated in one direction, and the overall strength of the nonwoven fabric is improved.

After the above nonwoven fabric is obtained, the nonwoven fabric can be adjusted to a desired thickness by heat treatment using a hot press machine or a conveyor type hot press machine. Secondary processing can be performed after the heat treatment, so that not only a flat plate but also an arbitrary shape can be obtained.

Further, the nonwoven fabric of the present invention may further comprise another fiber aggregate,
Alternatively, other sheets can be laminated to form a nonwoven fabric laminate. Examples of the sheet include a knitted fabric, a nonwoven fabric, a urethane foam, a film, a paper-like material, a wool molded product, a metal plate, a wooden plate, a plastic plate, and the like. The nonwoven fabric of the present invention is used in combination with these sheets and processed into various composite forms by, for example, laminating, sewing, heat sealing, and the like, and can be used for various applications. Also, laminating other materials within the range that does not hinder the effects of the present invention does not hinder at all.

The nonwoven fabric and the nonwoven fabric laminate can be used in various applications. However, since the nonwoven fabric and the nonwoven fabric laminate are used in combination with SAP, the use of a wiper, a liquid holding mat, a diaper, It can be preferably used for absorbent articles such as sanitary napkins.

The absorbent article of the present invention uses the above-mentioned nonwoven fiber aggregate, nonwoven fabric or nonwoven fabric laminate as a material for a liquid absorbent article. Specific examples of the liquid absorbent article include a newborn paper diaper that absorbs urine and loose stool, an infant paper diaper that mainly absorbs urine, a sanitary napkin, a wound pad,
Examples include a sweat-absorbing pad, a wiper for absorbing liquid, a sheet for absorbing liquid, and an underlaying material for a food tray. In short, any article that absorbs the liquid may be used.

In the superabsorbent fiber of the present invention, since SAP is buried in the thermoplastic fiber with a part of the SAP being exposed on the fiber surface, SAP can be prevented from moving and falling off.
Because SAP is not completely buried in thermoplastic fiber,
It can be expressed without reducing water absorption.
Further, since the bias such as the portion having a large amount of SAP and the portion having a small amount of SAP is unlikely to occur, it also has an effect of preventing the occurrence of gel blocking. That is, the SAP can be uniformly dispersed in the fiber aggregate, and the SAP can sufficiently exhibit water absorption.

[0025]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples. The SAP used in this example was manufactured by Sanyo Chemical Industries, Ltd. “Sunfresh ST-500MPS” (central particle size: 20 to 50 μm,
The absorption performance is about 400 g / g (deionized water). In addition, the measuring method or definition of the physical property value shown in the Example is collectively shown. 1 Number of crimps: Measured according to JIS-L-1015. 2 Single yarn fineness: measured according to JIS-L-1015. 3 Basis weight: The weight of the aggregate or nonwoven fabric cut into 50 cm squares was weighed and expressed as the weight per unit area (g / m ² ). 4 SAP shedding rate: The weight of the SAP contained in the aggregate or nonwoven fabric cut into 10 cm squares was defined as (W1), and then the amplitude was 3 cm, and the amplitude frequency was 1700 rpm. SAP contained in the aggregate or nonwoven fabric after sieving for 3 minutes under the conditions of
The weight (W2) was defined as (W2), and was calculated by the following equation. {(W1)-(W2)} (W1) × 100 = SAP shedding rate (%) 5 Water absorption: The weight (Z1) g of the SAP contained in the aggregate or nonwoven fabric cut into 10 cm squares was measured. After being immersed in ion-exchanged water for 5 minutes, the sample is taken out of the sample and allowed to stand until water drops drop, and the weight of water absorbed by the SAP is defined as (Z2) g. Further, the water absorption amount of only SAP was set to (Z3) g / g, and was calculated by the following equation. {(Z2) ÷ (Z1)｝ ÷ (Z3) × 100 = water absorption (%)

Table 1 shows the thermoplastic fibers used in the following Examples and Comparative Examples.

[0027]

[Table 1]

Example 1 Fiber 1 of Table 1 was passed through a container filled with SAP,
The fiber and SAP are in contact with each other,
By performing a heat treatment for 0 minutes, a part of the SAP is buried in the fiber in a state of being exposed on the fiber surface.
Into a nonwoven fiber aggregate by the airlaid method.
The synthetic fiber weight at that time was 100 g / m ² , and the weight of SAP was 3
0 g. Scanning electron micrographs of this fiber are shown in FIGS.

Example 2 Fiber 2 of Table 1 was passed through a container filled with SAP,
The fiber and SAP are in contact with each other,
By performing a heat treatment for 0 minutes, a part of the SAP is buried in the fiber in a state of being exposed on the fiber surface.
Into a nonwoven fiber aggregate by the airlaid method.
The synthetic fiber weight at that time was 100 g / m ² , and the weight of SAP was 3
0 g.

Example 3 The fibers 3 of Table 1 were passed through a container filled with SAP,
The fiber and SAP are in contact with each other,
By performing a heat treatment for 0 minutes, a part of the SAP is buried in the fiber in a state of being exposed on the fiber surface.
Into a nonwoven fiber aggregate by the airlaid method.
The synthetic fiber weight at that time was 100 g / m ² , and the weight of SAP was 3
0 g.

Example 4 Fiber 4 of Table 1 was passed through a container filled with SAP,
The fiber and SAP are in contact with each other,
By performing a heat treatment for 0 minutes, a part of the SAP is buried in the fiber in a state of being exposed on the fiber surface.
Into a nonwoven fiber aggregate by the airlaid method.
The synthetic fiber weight at that time was 100 g / m ² , and the weight of SAP was 3
0 g.

Example 5 Fiber 1 of Table 1 was passed through a container filled with SAP.
The fiber and SAP are in contact with each other,
By performing a heat treatment for 0 minutes, a part of the SAP is buried in the fiber in a state of being exposed on the fiber surface.
m was cut into a nonwoven fiber aggregate by a card method. The synthetic fiber weight at that time is 100 g / m ² , and the weight of SAP is 30
g.

Example 6 Fiber 1 shown in Table 1 was cut into 5 mm, mixed with SAP, and formed into a nonwoven fiber aggregate by an airlaid method.
By performing the treatment at 10 ° C. for 10 minutes, the SAP was buried while leaving a part of the SAP on the fiber surface, and a non-woven fabric was obtained. At that time, the synthetic fiber weight was 100 g / m ² and the weight of the SAP was 30 g.

Example 7 Fiber 2 shown in Table 1 was cut into 5 mm, mixed with SAP, and formed into a nonwoven fiber aggregate by an airlaid method.
At 10 ° C. for 10 minutes, the SAP was buried in the fiber in a state where a part of the SAP was exposed on the fiber surface, and a nonwoven fabric was obtained. The synthetic fiber weight at that time is 100 g / m ² , SAP
Was 30 g in weight.

Example 8 Fiber 1 shown in Table 1 was cut into 51 mm, mixed with SAP,
It was made into a nonwoven fiber aggregate by the card method.
At 10 ° C. for 10 minutes, the SAP was buried in the fiber in a state where a part of the SAP was exposed on the fiber surface, and a nonwoven fabric was obtained. The synthetic fiber weight at that time is 100 g / m ² , SAP
Was 30 g in weight.

Comparative Example 1 Fiber 1 shown in Table 1 was cut into 5 mm, mixed with SAP, and made into a nonwoven fiber aggregate by an airlaid method. At that time, the synthetic fiber weight was 100 g / m ² and the weight of the SAP was 30 g.

Comparative Example 2 Fiber 3 shown in Table 1 was cut into 5 mm, mixed with SAP, and made into a nonwoven fiber aggregate by an airlaid method. At that time, the synthetic fiber weight was 100 g / m ² and the weight of the SAP was 30 g.

Comparative Example 3 Fiber 1 shown in Table 1 was cut into 51 mm and mixed with SAP.
It was made into a nonwoven fiber aggregate by the card method. At that time, the synthetic fiber weight was 100 g / m ² and the weight of the SAP was 30 g.

Comparative Example 4 Fiber 1 shown in Table 1 was cut into 5 mm pieces to form a nonwoven fiber aggregate by an air laid method, and processed at 140 ° C. for 10 minutes to obtain a nonwoven fabric. Thereafter, the SAP was laminated. The synthetic fiber weight at that time is 100 g / m ² , and the weight of SAP is 30
g.

Comparative Example 5 The fiber 2 shown in Table 1 was cut into 51 mm, made into a nonwoven fiber aggregate by a card method, and treated at 140 ° C. for 10 minutes to obtain a nonwoven fabric. Thereafter, the SAP was laminated. The synthetic fiber weight at that time is 100 g / m ² , and the weight of SAP is 30 g.
And

Comparative Example 6 Fiber 1 of Table 1 was passed through a container filled with SAP.
The fiber and SAP are in contact with each other,
The heat treatment was performed for 5 minutes, and then the pressure was applied with a hot roll at 150 ° C. to bury the SAP entirely in the fiber, and then the SAP was cut into 5 mm, and a nonwoven fiber aggregate was formed by an airlaid method. At that time, the synthetic fiber weight was 100 g / m ² and the weight of the SAP was 30 g.

Table 2 shows the measurement results of the SAP shedding rate and the water absorption of the fiber aggregates or nonwoven fabrics obtained in Examples 1 to 8 and Comparative Examples 1 to 6.

[0043]

[Table 2]

Example 9 The nonwoven fabric of Example 6 was cut into a size of 15 cm × 15 cm, and laminated with a polyethylene film of the same size.
An emboss heat treatment was performed at 5 ° C. to obtain a wiper for wiping the floor.

Example 10 The nonwoven fabric of Example 6 was cut into a size of 10 cm × 25 cm, and the whole cut nonwoven fabric was wrapped with tissue to obtain an absorbent for a disposable diaper.

Comparative Example 7 The nonwoven fabric of Comparative Example 4 was cut into a size of 15 cm × 15 cm and laminated with a polyethylene film of the same size.
An emboss heat treatment was performed at 5 ° C. to obtain a wiper for wiping the floor.

Comparative Example 8 The nonwoven fabric of Comparative Example 4 was cut into a size of 10 cm × 25 cm, and the whole cut nonwoven fabric was wrapped with a tissue to obtain an absorbent for a disposable diaper.

As is evident from Table 2, the nonwoven fiber aggregates and nonwoven fabrics of the present invention in Examples 1 to 8 prevent SAP from falling off and exhibit their water absorption with almost no decrease in water absorption. It is also effective as an absorbent article. In Comparative Examples 1 to 5, since SAP was not partially buried in the fiber, SAP dropped off sharply. Conversely, Comparative Example 6
Since all of P is buried in the fiber, SAP does not fall off, but the original water absorption does not appear.

Comparing Example 9 with Comparative Example 7, Example 9 has high SAP retention and good water absorption, so that when used as a wiper, the removal of excess water is quick and the workability is high. Significantly improved. Also, Comparative Example 7
Since P is dropped, workability is significantly reduced, and further, since the SAP amount is reduced, the absolute water absorption is reduced.

Comparison between Example 10 and Comparative Example 8 shows that Example 10 has high SAP retention and good water absorption, and therefore does not exhibit partial deviation of SAP when used as an absorber, and is uniform. Water absorption is obtained. In Comparative Example 8, since the SAP moves, the SAP bias appears. Therefore, gel blocking occurs and the absolute water absorption of SAP is reduced.

[0051]

The superabsorbent fibers and nonwoven fabric of the present invention are:
By burying a part of the SAP in the fiber, the SAP
Of the SAP, by exposing a part thereof to the surface of the fiber, thereby exhibiting the water absorbing performance of the SAP.
Does not hinder the SAP expansion to near the water absorption capacity of the SAP. That is, water is absorbed stepwise while suppressing gel blocking. Therefore, even when subjected to vibration during storage or transportation when used for absorbent articles, SAP movement, falling off is prevented,
When used, SAP performance can be sufficiently exhibited.

[Brief description of the drawings]

FIG. 1 is a scanning electron micrograph showing an example of the superabsorbent fiber of the present invention.

FIG. 2 is a scanning electron micrograph showing an example of the superabsorbent fiber of the present invention.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B32B 5/02 A41B 13/02 D 4L047 D04H 1/54 A61F 13/18 307F 1/72 307G F term (Reference) ) 3B029 BA05 BA18 4C003 AA27 AA28 4C098 AA09 CC01 DD05 DD10 DD25 DD26 4F100 AJ07 AK01A AK01B AK05 AK07 AK25 AL05A AL06 AT00B BA02 BA03 DD31 CADG ABB12 J03A DG15B12A13 4L047 AA14 AA21 AA23 AA27 AB02 AB10 BA07 BA08 BA23 CA04 CA05 CA06 CB07 CB10 CC04 CC05 EA02

Claims (12)

[Claims] 1. A superabsorbent fiber comprising a thermoplastic fiber and a superabsorbent resin, wherein the superabsorbent resin is buried in the thermoplastic fiber and a part thereof is exposed on the fiber surface. Has super absorbent fiber. 2. The superabsorbent fiber according to claim 1, wherein the thermoplastic fiber is a thermoplastic conjugate fiber composed of two or more resins having different melting points. 3. The superabsorbent fiber according to claim 1, wherein the relationship between the diameter (X) of the thermoplastic fiber and the average particle size (Y) of the superabsorbent resin is X> Y. 4. The superabsorbent fiber according to claim 1, wherein the form of the superabsorbent fiber is a nonwoven fiber aggregate. 5. The superabsorbent fiber according to claim 1, wherein the superabsorbent fiber is a nonwoven fiber aggregate obtained by an airlaid method. 6. A nonwoven fabric comprising the superabsorbent fiber according to claim 1. 7. A nonwoven fabric obtained by heat-treating the superabsorbent fiber according to any one of claims 1 to 5. 8. A nonwoven fabric laminate obtained by laminating the nonwoven fabric according to claim 6 and another sheet. 9. The nonwoven fabric laminate according to claim 8, wherein the other sheet is at least one of a nonwoven fabric, a film, a knit, and a woven fabric. 10. An absorbent article using the superabsorbent fiber according to any one of claims 1 to 5. 11. An absorbent article using the nonwoven fabric according to claim 6. 12. An absorbent article using the nonwoven fabric laminate according to claim 8.