CN112869955A

CN112869955A - Liquid-absorbing article such as sanitary napkin and disposable diaper

Info

Publication number: CN112869955A
Application number: CN202011341436.9A
Authority: CN
Inventors: 见正伸夫; 古濑直树
Original assignee: Unitika Ltd
Current assignee: Unitika Ltd
Priority date: 2019-11-30
Filing date: 2020-11-25
Publication date: 2021-06-01

Abstract

The invention provides a liquid-absorbent article which has a good feel and can rapidly absorb body fluid and is less sticky. The liquid-absorbent article is formed by laminating a surface material (1), a body fluid absorber (2), and a leakage-preventing material (3) in this order. The surface material (1) is formed of a nonwoven fabric in which cotton fibers are three-dimensionally entangled with each other. The cotton fibers are preferably non-absorbent cotton. In addition, long fibers may be interwoven with cotton fibers. The nonwoven fabric is provided with funnel-shaped perforations (11) having a diameter that decreases from the skin side toward the body fluid absorber 2 side. In addition, a recess (12) recessed from the skin side toward the body fluid absorbent body 2 side may be provided together with the funnel-shaped perforation (11). The liquid-absorbing article is used so that the surface material (1) is in contact with the skin, and specifically, the convex portions (13) of the surface material (1) are in contact with the skin.

Description

Liquid-absorbing article such as sanitary napkin and disposable diaper

Technical Field

The present invention relates to a liquid-absorbent article such as a sanitary napkin or a disposable diaper, and more particularly to a liquid-absorbent article which has a good feel and can rapidly absorb body fluid and is less sticky.

Background

Liquid-absorbent articles such as sanitary napkins and disposable diapers are articles in which a surface material, a body fluid absorber, and a leakage preventing material are laminated in this order from the skin side. Conventionally, a synthetic resin film provided with funnel-shaped perforations has been used as the surface material (patent document 1 and non-patent document 1). The surface material is called a dry mesh sheet because the synthetic resin film itself does not absorb body fluid and is therefore less sticky (non-patent document 1). However, the dry web is formed of a synthetic resin film, and thus has a disadvantage of poor touch.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2001 and 9908

Non-patent document

Non-patent document 1: https:// jp.pg.com/japan40yrs/case/03whisper.jsp

Disclosure of Invention

In order to improve the touch of the dry mesh sheet, it is considered to dispose a cotton fiber layer on the surface thereof. However, since the cotton fibers themselves easily absorb body fluids, they are likely to be sticky, and thus are not considered to be usable as a dry mesh sheet.

However, it has been found that the stickiness of the surface material is reduced by using a nonwoven fabric made of specific cotton fibers without using a synthetic resin film and by bringing the nonwoven fabric as the surface material into contact with the body fluid absorbent body. Accordingly, an object of the present invention is to provide a liquid-absorbent article which has a good feel, can quickly absorb body fluid, and is less sticky.

That is, the present invention relates to a liquid-absorbent article in which a surface material 1, a bodily fluid absorber 2, and a leakage preventing material 3 are laminated in this order, and the surface material 1 is in contact with the skin, wherein the surface material 1 is formed by providing funnel-shaped perforations 11, the diameter of which is reduced from the skin side toward the bodily fluid absorber side, in a nonwoven fabric formed by three-dimensionally interweaving cotton fibers, or is formed by providing recesses 12, which are recessed from the skin side toward the bodily fluid absorber side, together with the funnel-shaped perforations 11, and the surface material 1 is in contact with the bodily fluid absorber 2.

The liquid-absorbent article of the present invention uses a nonwoven fabric in which cotton fibers are three-dimensionally entangled as the surface material 1. That is, since synthetic resin such as an adhesive is not used, the cotton fibers are in contact with the skin, and the touch feeling is good. Further, since the surface material 1 is provided with the funnel-shaped perforation holes 11, the bodily fluid can be absorbed quickly. Further, since the front end face (end face on the body fluid absorbent member 2 side) of the funnel-shaped perforation 11 is in contact with the body fluid absorbent member 2, the body fluid absorbed by the portion of the surface material 1 other than the perforation 11 is also rapidly absorbed from the front end face, and stickiness is reduced. In particular, if the concave portion 12 is provided together with the funnel-shaped perforation 11, the bottom surface of the concave portion 12 comes into contact with the body fluid absorbent member 2, and therefore the body fluid accumulated on the bottom surface of the concave portion 12 is quickly absorbed and less sticky.

Drawings

Fig. 1 is a schematic cross-sectional view showing a part of a liquid-absorbent article according to an example of the present invention.

Fig. 2 is an enlarged schematic view showing an example of a portion a shown by a square in fig. 1.

Fig. 3 is an enlarged schematic view showing another example of the portion a shown by a square in fig. 1.

Fig. 4 is an enlarged schematic view showing still another example of the portion a shown by a square in fig. 1.

Description of the symbols

1 surface Material

2 body fluid absorber

3 leak-proof material

11 funnel-shaped perforation

12 recess

13 convex part contacting with skin

Detailed Description

The liquid-absorbent article of the present invention is formed by laminating a topsheet 1, a body fluid absorbent body 2 and a leakage preventing material 3 in this order. The surface material 1 is used in contact with the skin. As the body fluid absorber 2, a conventionally known body fluid absorber such as pulp fiber or granular polymer absorber can be used. As the leakage preventing material 3, a conventionally known leakage preventing material such as a synthetic resin film is also used.

The surface material 1 is formed of a nonwoven fabric in which cotton fibers are three-dimensionally entangled with each other. In order to three-dimensionally interlace the cotton fibers with each other, a water-jet interlacing treatment may be performed on a cotton fiber web obtained by opening and collecting the cotton fibers with a carding machine. As the cotton fiber, conventionally known cotton fibers can be used, but non-cotton wool is particularly preferably used. Non-absorbent cotton is cotton fiber from which oil and fat components such as cottonseed oil contained in natural cotton fiber have not been completely removed. When absorbent cotton completely free of fat and oil components is used, the cotton fiber itself tends to absorb body fluid and to become sticky during use. Therefore, in the case of non-absorbent cotton, there is an advantage that the absorbency of body fluid of the cotton fiber itself is lowered and stickiness is reduced. In addition, in order to reduce the body fluid absorbency of the cotton fiber itself, a water repellent agent may be added to the cotton fiber. Furthermore, as the cotton fiber, bleached cotton is preferably used, and especially non-degreased bleached cotton is preferably used. This is because if bleached in advance, the color becomes white, and a clean feeling is imparted to the liquid-absorbent article.

In the present invention, a nonwoven fabric in which cotton fibers are three-dimensionally entangled with each other and the cotton fibers and long fibers may be used as the surface material 1. In the nonwoven fabric, the above-described cotton fiber web may be laminated on a coarse filament nonwoven fabric, and water-flow interlacing treatment may be performed from the cotton fiber web side and/or the filament nonwoven fabric side. The nonwoven fabric is improved in mechanical strength and form stability because long fibers are mixed therein. As the long fiber nonwoven fabric, conventionally known spunbond nonwoven fabrics composed of thermoplastic long fibers can be used, and for example, polypropylene spunbond nonwoven fabrics, polyester spunbond nonwoven fabrics, or spunbond nonwoven fabrics composed of core-sheath type composite fibers in which the core is polyester and the sheath is polyethylene are used.

The weight per unit area of the nonwoven fabric is 10 to 40g/m²Left and right. If the weight per unit area is less than 10g/m²The mechanical strength and form stability of the surface material 1 tend to be lowered. Further, if the weight per unit area exceeds 40g/m²The surface material 1 tends to be rigid and hard to contact the body fluid absorbent member 2 and to be in contact with the skin. When a nonwoven fabric is obtained by laminating a cotton fiber web and a long fiber nonwoven fabric, the weight ratio of the two is preferably: long fiber nonwoven fabric 1: less than 1. If the proportion of the long fiber nonwoven fabric is high, the feeling tends to be low.

As shown in fig. 2, the surface material 1 is provided with funnel-shaped perforations 11. The perforations 11 may be formed by passing the nonwoven fabric between a male roll having needle-like projections having a conical shape at the tip and a female roll having recesses into which the needle-like projections can be fitted. When the constituent fibers of the nonwoven fabric are 100% cotton fibers, the convex roll may be at room temperature, but when thermoplastic long fibers are mixed in the cotton fibers, the convex roll is preferably heated. This is because if the convex roll is at normal temperature, the thermoplastic long fibers hardly follow the funnel-like form. The heating temperature may be a temperature at which the thermoplastic long fibers are softened, and may be, for example, about 100 to 200 ℃. The diameter of the perforations 11 on the skin side is

The left and right sides gradually narrow toward the body fluid absorber 2. The density of the perforations 11 is arbitrary, but is generally 5 to 200 per 25mm²Left and right.

As shown in fig. 3, it is preferable that a concave portion 12 depressed from the skin side toward the bodily fluid absorbent body 2 side is provided in the surface material 1 together with the funnel-shaped perforation 11. The concave portion 12 can be formed by passing the nonwoven fabric between a convex roller having a flat surface at the tip and having flat protrusions of any shape such as an oval shape, a circular shape, or a square shape, and a concave roller having a concave portion capable of fitting the flat protrusions. Therefore, the surface material 1 having the perforations 11 and the recesses 12 is obtained by passing the nonwoven fabric between a male roll having needle-like protrusions and flat protrusions and a female roll having recesses capable of fitting with the needle-like protrusions and recesses capable of fitting with the flat protrusions. In this case, when the long fibers are mixed with the cotton fibers, the convex roller is preferably heated for the same reason as described above. The size of the recess 12 is arbitrary and can be used in a wide range, but is generally 1 to 50mm²Left and right. The concave portion 12 has a function of reducing a sticky feeling in use and has a surfaceThe density is arbitrary because of the function of the pattern on the surface of the material 1. That is, when a certain pattern is desired to be formed on the surface of the surface material 1, the concave portions 12 may be arranged so as to form the pattern.

In the embodiment shown in fig. 4, a concave portion 12 recessed from the skin side toward the body fluid absorbent body 2 side may be provided in the surface material 1 together with the funnel-shaped perforation 11. That is, funnel-shaped through-holes 11 may be provided in the bottom surface of the recess 12. In this case, the nonwoven fabric may be passed between a male roll having a hemispherical recess provided in the flat surface and a needle-like protrusion provided around the recess, and a female roll having a hemispherical protrusion capable of fitting into the hemispherical recess provided in the flat surface and a recess capable of fitting into the needle-like protrusion provided around the protrusion. The concave part 12 is formed by the flat surface of the concave-convex roller, and the funnel-shaped through hole 11 is provided by the needle-shaped protrusion of the convex roller. Further, convex portions 13 contacting the skin are provided by the hemispherical protrusions of the concave roller. Other points are the same as those in fig. 2 and 3.

The liquid-absorbent article of the present invention is obtained by laminating the bodily fluid absorbent body 2 and the leakage preventing material 3 in this order so that the topsheet 1 described above is the skin side. In this liquid-absorbent article, the skin comes into contact with the convex portions 13 of the surface material 1, and the convex portions 13 are mainly made of cotton fibers, so that the touch is good.

Examples

Example 1

Hanging cotton fiber on a carding machine, opening and collecting to obtain a weight of 35g/m²The cotton fiber web of (1). The cotton fiber web was carried on a 100-mesh wire support and introduced into a water jet apparatus. The water jet device was a device in which nozzle holes having an aperture of 0.1mm were horizontally arranged in a line at a hole interval of 0.6mm, and cotton fibers were entangled with each other by applying water jet pressure of 2.8MPa from the side of the cotton fiber web. Thereafter, the nonwoven fabric was introduced into the water jet apparatus and water was applied twice at a jet pressure of 5.5MPa to obtain a nonwoven fabric in which cotton fibers were three-dimensionally entangled with each other.

The nonwoven fabric was passed through a convex roll having needle-like protrusions (surface temperature was constant)Warm) and a concave roller having a recess into which the needle-like projections are fitted, to obtain a surface material. The needle-like protrusions are conical, and the diameter of the bottom surface is

The density of the powder is 161/25 mm²。

Example 2

A nonwoven fabric was obtained in the same manner as in example 1. The nonwoven fabric was passed between a convex roll (surface temperature was room temperature) having needle-like protrusions and flat protrusions and a concave roll having recesses into which the needle-like protrusions and the flat protrusions were fitted, to obtain a surface material. The needle-like projections and the flat projections are arranged in 1 row with respect to 3 rows of the needle-like projections arranged in a staggered manner. The needle-like projections are conical, and the bottom surface has a diameter of

The front end surface of the flat protrusion is circular in shape and has a diameter of

In addition, the density of the needle-like projections was 96 per 25mm²The density of the flat protrusions is 32/25 mm²。

Example 3

Hanging cotton fiber on a carding machine, opening and gathering to prepare 20g/m weight per unit area²The cotton fiber web of (1). On the other hand, a weight per unit area of 13g/m was prepared²The polypropylene long fiber nonwoven fabric of (1). The prepared laminate obtained by laminating the cotton fiber web and the long fiber nonwoven fabric was carried on a 100-mesh wire support, introduced into the water jet apparatus used in example 1, and treated by the same treatment method as in example 1 to obtain a three-dimensionally entangled nonwoven fabric. In the nonwoven fabric, cotton fibers are three-dimensionally entangled with each other, and the cotton fibers and the long fibers are also three-dimensionally entangled with each other. The nonwoven fabric was passed through a convex roll (surface temperature: 130 ℃) having hemispherical depressions formed in a flat surface and needle-like protrusions formed around the depressions, and a hemisphere having a hemispherical shape fittable into the hemispherical depressionsThe surface material was obtained between the projections and recessed concave rollers (surface temperature: 130 ℃ C.) capable of fitting the needle-like projections provided around the projections. Diameter of convex roller

The hemispherical depressions of (2) are regularly and uniformly arranged in a staggered pattern, and needle-like protrusions (conical shape with a bottom diameter of 3 pieces) are provided around the depressions at a ratio of 3 pieces/depression

The needle-like protrusions) of (2), the portions other than the hemispherical depressions and the needle-like protrusions are flat surfaces. The arrangement density of the hemispherical recesses was 3/cm²。

Example 4

Hanging cotton fiber on a carding machine, opening and gathering to prepare 20g/m weight per unit area²The cotton fiber web of (1). On the other hand, a weight per unit area of 13g/m was prepared²The long fiber nonwoven fabric (product of Yonigaku K.K., SO133 WGO). The prepared cotton fiber web and long fiber nonwoven fabric were stacked and transported on a 100-mesh wire support, introduced into the water jet apparatus used in example 1, and treated by the same treatment method as in example 1. As a result, a nonwoven fabric in which cotton fibers are three-dimensionally entangled with each other and cotton fibers and long fibers are also three-dimensionally entangled with each other was obtained.

The nonwoven fabric was passed between the male roll and the female roll used in example 1 to obtain a surface material. However, the surface temperature of the convex roll was 125 ℃.

Example 5

The nonwoven fabric obtained in example 4 was passed between the male roll and the female roll used in example 2 to obtain a surface material. However, the surface temperature of the convex roll was 125 ℃.

Comparative example 1

The nonwoven fabric obtained in example 1 was used as a surface material without passing through between a male roll and a female roll.

Comparative example 2

The nonwoven fabric obtained in example 3 was used as a surface material without passing it between a male roll and a female roll.

The surface materials obtained in examples 1 to 5 and the surface materials obtained in comparative examples 1 and 2 were placed on a body fluid absorber equivalent (three layers of filter paper of GRADE: 989), and the moisture permeability [ liquid absorption rate (sec) ] of artificial urine was measured using artificial urine having a surface tension of 70dyn/cm using a liquid absorption measuring apparatus LISTER AC (LENZING INSTRUMENT, Inc.). The results are shown in table 1.

[ Table 1]

It is understood that the surface materials of examples 1 to 5 are superior in moisture permeability to the surface materials of comparative examples 1 and 2, and that the liquid-absorbent article using the surface materials of examples 1 to 5 can rapidly absorb body fluid and is less sticky when used.

Claims

1. A liquid-absorbent article characterized in that a surface material, a body fluid absorber and a leakage preventing material are laminated in this order, the surface material being in contact with the skin,

the surface material is formed by arranging funnel-shaped perforations with a diameter decreasing from the skin side to the body fluid absorbent body side on a non-woven fabric formed by three-dimensionally interweaving cotton fibers,

the surface material is in contact with the bodily fluid absorbent.

2. The liquid-absorbent article according to claim 1, wherein the nonwoven fabric is provided with a concave portion recessed from the skin side toward the body fluid absorbent body side together with the funnel-shaped perforation.

3. The liquid-absorbent article according to claim 1, wherein non-absorbent cotton is used as the cotton fiber.

4. The liquid-absorbent article according to claim 1, wherein the nonwoven fabric is a nonwoven fabric formed by three-dimensionally interlacing cotton fibers with each other and cotton fibers and long fibers.