JPH04161154A - Surface material for absorptive article - Google Patents

Abstract

PURPOSE:To satisfactorily satisfy each of absorptivity and liquid return preventability, and also, to maintain the satisfactory feeling by forming a first layer consisting of an assembly of fibers positioned in the skin side of the human body to a plane sheet shape, and forming a second layer consisting of an assembly of fibers positioned in an absorbing body side to a sheet shape having many duct-like projecting parts. CONSTITUTION:Excretions of the skin side of the human body pass through a first layer sheet 7. In this case, a first layer is constituted of fibers having a prescribed size, and the excretions pass through without receiving particular flow resistance, and reach a second layer sheet 8. The excretions contained in a recessed part 9 transmit through a second layer sheet 8 itself or a duct-like projecting part 10 and are absorbed by an absorbing body 2. The excretions flowing directly to a through-hole 12 from a first layer sheet 7 pass directly through a space 11 and are absorbed directly by the absorbing body 2. On the other hand, in the case body pressure is applied to a sanitary napkin 1, the excretions in the recessed part 9 move extending over the whole in the recessed part 9 whose passage resistance is smaller than a first layer sheet 7, and the body pressure is allowed to escape by utilizing the whole of a second layer sheet. Accordingly, it does not occur that the excretions ooze out to the surface of a first layer.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a surface material for absorbent articles such as disposable diapers and sanitary hygiene products.

[Prior Art] In general, surface materials of absorbent articles such as disposable diapers and sanitary hygiene products are required to have texture, absorbency, and liquid return prevention functions. "Absorbency" refers to the property that excreted urine, blood, etc. is absorbed in a short time. This refers to the ability to prevent excrement from flowing back into the wearer's body.

Currently, the surface materials used in this field include those using synthetic resin film for the part that comes into contact with the wearer's skin, and P
E (polyethylene), PET (polyester), PP (
There are two main types: synthetic fibers made of synthetic fibers such as polypropylene, which are laminated in a web shape. Among these, products using the above-mentioned film have recently been widely used, but many users dislike the film-like texture. These people prefer facings made of synthetic fibers. Conventional techniques that consider surface materials using synthetic fibers from the functional aspects such as absorbency and liquid return properties include JP-A No. 2-4369 and JP-A No. 42-6114.
No. 9 etc. are publicly known. The former improves absorbency by making the surface of the fibers constituting the surface material hydrophilic with an oil agent (active side that modifies the properties of the fiber surface for boat fishing). In the latter method, a web with a basis weight of 15 to 30 gr/rrf is punctured with a needle, and the absorbency of excrement is improved through the holes. These conventional techniques contribute to improving absorbency, but in all of them, the surface material is composed of a single layer.

[Problem to be solved by the invention] However, since the surface material is a single layer, that is, a fiber aggregate layer with a continuous cross-sectional direction, it retains the absorbed excrement and promotes absorbency. The retention amount can be further increased by adding an oil agent.

Therefore, in the former case mentioned above, the pressure applied to the absorbent article by the wearer during use may cause the absorbed excrement to come out on the surface of the surface material, causing discomfort to the user and leakage of excrement. I wake up.

When considering absorbency and liquid return prevention properties, absorbency can be improved by reducing the flow resistance when excrement passes through the surface material, but in order to do so, it is necessary to use a surface material composed of fiber aggregates. In this case, it is sufficient to increase the distance between the intertwining points of the fibers.

In other words, it is possible to consider ways to increase the hole area ratio.

However, the constituent fibers are generally synthetic fibers such as PE (polyethylene) and PET (polyester). A predetermined absorbency is obtained by controlling the degree.

On the other hand, regarding liquid return prevention, it is necessary to prevent excrement on the absorber side from coming out onto the surface material, and for this purpose, it is desirable that flow resistance is large, and hydrophobic rather than hydrophilic. Preferably gender.

In this way, liquid absorbency and liquid return property are required to have opposite functions, and there is a relationship in which if the absorbency is excellent, the liquid return property is inferior, and it has been impossible to achieve a balance between the two.

Therefore, an object of the present invention is to provide a surface material for an absorbent article that satisfies both absorbency and liquid return prevention properties and maintains a good texture as a surface material made of fiber aggregate. be.

[Means to solve the problem]

The present invention provides a surface absorbent article having a first layer made of an aggregate of fibers located on the skin side of a human body and a second layer made of an aggregate of fibers located on the absorbent body side that absorbs excrement. The first layer is formed into a substantially planar sheet shape, the second layer is formed into a sheet shape having a large number of duct-like protrusions, and the tips of the duct-like protrusions include The above object has been achieved by providing a surface material for an absorbent article, which is characterized in that each of the duct-like protrusions is provided with a hole, each of the duct-like protrusions is surrounded by a recess, and each of the recesses is in communication with each other. It is something.

[Effect]

According to the absorbent article using the surface material of the present invention, excrement on the skin side of the human body when worn first passes through the first layer of the surface material; Passes through without significant flow resistance.

Then, the excrement reaches the second layer, but some of the excrement
Through the hole of the duct-like protrusion, it is directly guided to the absorbent body and absorbed, and the other part of the excrement flows into the recess, but the excrement that flows into the recess passes through the fibers forming the recess. and is guided to the absorber.

On the other hand, when pressure such as body pressure is applied to the absorbent article, the resistance of excrement in the recesses to move between the recesses that communicate with each other is sufficiently smaller than the flow resistance that is experienced by the distance between the first layer fibers. Therefore, it moves between the recesses and releases the applied pressure. Therefore, even if body pressure or the like is applied to the absorbent article, excrement will not ooze out onto the surface of the first layer that is in contact with the wearer's skin.

〔Example〕

A preferred embodiment of the present invention will be described below with reference to the accompanying drawings.

As shown in FIGS. 2 and 3, the sanitary napkin 1 according to this embodiment is provided with an absorbent body 2 in the center that absorbs excrement, and the surface material 3 according to this embodiment absorbs the excrement. body 2
It encompasses the whole thing. This surface material 3 is formed into a single sheet, and is welded to the back side of the absorbent body 2 to form a bag shape.

A waterproof sheet 4 is placed between the absorbent body 2 and the surface material 3, covering the back side of the absorbent body 2, to prevent excrement absorbed from the front side from leaking to the back side and both sides. There is.

Further, at both ends of the sanitary napkin 1, the surface material 3 and the waterproof ring 14 are bonded together by thermocompression, thereby forming a leak prevention part 5.

As shown in a partially enlarged view in FIG. 1, the surface material 3 includes a first layer sheet 7 located on the surface that comes into contact with the skin when worn;
It is provided on the back side of the first layer sheet 7 and includes a second N port 8 located on the absorber 2 side.

Both the first layer sheet 7 and the second layer sheet 8 are formed from fiber aggregates, but the first layer sheet 7 is formed into a substantially flat sheet, and the second layer sheet 8 is formed into a substantially flat sheet. is formed in an uneven shape.

That is, the second layer sheet 8 has a large number of duct-like protrusions 1° formed therein. The upper end 10a of this duct-like protrusion 1o is coupled to the end surface 7a of the first layer sort 7 by thermal fusion or physical entanglement of the fibers. As a result, a space 11 corresponding to the height of the duct-like protrusion 10 is maintained between the first layer sort 7 and the absorbent body 2, and the first layer sheet 7 and the second layer sheet 8 are separated. The two layers are integrated.

Incidentally, the surface material 3 may be formed by simply overlapping both sheets without combining both sorts.

A through hole 12 is formed in the center of the hole of the duct-like protrusion 10, and a recess 9 is formed around the hole. These recesses 9 are open to the first layer sheet 7 side, and the circular through holes 12 are directly connected to the first layer sheet 7 and the absorbent body 2.

Further, a duct-like protrusion 10 that partitions the recess 9 and the through hole 12 is provided.
is formed from a fiber aggregate, and the excrement in the recess 9 passes through the tallite-like protrusion 10 and is guided to the absorbent body 2.

Such a second layer sheet 8 is manufactured as follows.

Thermoplastic fibers are heated and melted and supplied to the endless breathable conhair 20 having a network structure shown in FIGS. 4 and 5, while suction is applied from below or air is injected from above to form breathable conhair. It is manufactured by fusing it to 20 and winding it up. As shown in FIG. 5, the breathable con-hair 20 has irregularities formed on its surface, and it is preferable that the height difference is set to 3 to 8 square meters. If the difference in height is less than 3 degrees, it is difficult to form irregularities on the 211th sheet 8, or perforations in combination with the irregularities.On the other hand, if the difference in height exceeds 8 degrees, the second layer sheet 8 after forming the irregularities will be difficult to form. This is because it becomes difficult to peel off, which is undesirable. Further, it is preferable that the number of convex portions is set to 10 to 25 (n2).

The number of convex parts has increased to 10 to 8! If it is less than 25 fibers/in'', structural fibers are likely to be scattered by the ejected air flow, and if it exceeds 25 fibers/in'', it will be difficult to form unevenness.

Further, the first layer sheet 7 is made of fibers having a predetermined fineness so that viscous substances in excrement can easily pass through, and the liquid retention property is kept to a minimum.

In order to satisfy the texture of the surface material obtained in this example and to allow the excrement to pass through easily, the first layer sheet 7 is made of fibers of 2d (denier) to 6d, preferably 4d to 6d. It is preferable to use one in which 50 to 70% by weight of 6d fibers are mixed, and the rest consists of 0.5d to 2d fibers.

In addition, in order to integrate these, each fiber is 90 to 200
Each fiber may have a function of heat-sealing with C.

In addition, from the perspective of minimizing liquid retention, the basis weight is 6.
In the range of gr/I to 15gr/bo, preferably 8g
It is preferable that it has a relatively low density of r/po to 10 gr/po and that it is subjected to 6 hydrophilic treatment so that the sedimentation rate is in the range of 4 to 7 seconds.

The fibers used in these materials include single fibers such as polyethylene, polypropylene, polyester, and low melting point polyester, or composite fibers made by combining these fibers.

The second layer sheet does not require a special fiber structure, but it has a basis weight of 10 gr/m to facilitate the guide of excrement to the absorbent side.
It is preferable to use fibers in the range of 0.5 to 4 d. Further, in order to integrate these, it is preferable that each fiber has a thermal Ia adhesion function, similar to the first layer sheet 7. In order to further facilitate the introduction of excrement, it is preferable to perform a hydrophilic treatment so that the sedimentation time is in the range of 2 to 3 seconds. is as follows.

First, we took 5 grams of each fiber mass and made it using copper wire with a diameter of 0.5 mm, a diameter of 50 mm, a depth of 80 m, and a distance of 2 between the heel and the wire.
When placed in a test basket with a cylindrical diameter and weighing approximately 3 grams, the basket was placed on its side and gently dropped into room-temperature water at a depth of approximately 200 mm from a height of approximately 10 mm above the water surface. Time the time it takes to sink to the bottom. The number of tests was 12, and the average value represents the hydrophilicity of the fiber.

Next, the operation according to this embodiment will be explained.

When using the sanitary napkin 1 using the surface material according to this embodiment, the human body's excrement on the skin side penetrates the first layer sheet 7. At this time, the first layer is made of fibers with a predetermined fineness, and does not experience any particular flow resistance.
Then, the second layer sheet 8 is reached.

In the second layer sheet 8, the excrement stored in the recesses 9 is
It passes through the layer sheet 8 itself or the duct-like protrusion 10 and is absorbed into the absorbent body 2 .

The excrement flowing directly from the first layer sheet 7 to the through hole 12 flows directly through the space 11 i! Then, it is directly absorbed into the absorbent body 2.

On the other hand, when body pressure is applied to the sanitary napkin, the excrement in the recess 9 moves throughout the recess 9, which has a lower passage resistance than the first layer sheet 7, and spreads throughout the second layer sheet. Use this to relieve body pressure.

Note that the excrement present in the through hole 12 is immediately absorbed by the absorbent body 2, so it does not remain in the through hole 12.

Furthermore, since the space 11 is elastically held by the duct-like protrusion 10, it is soft and feels good when worn.

In addition, in the surface material of this example, since the first layer sheet on the surface side has a flat shape, it provides a good texture as a fiber aggregate type surface material.

〔Effect of the invention〕

According to the surface material of an absorbent article of the present invention, it is possible to improve each of absorbency and liquid return property, and maintain a good texture as a surface material made of a fiber aggregate.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of the surface material of the present invention, FIG. 2 is a cross-sectional view of an absorbent article using the surface material of the present invention, and FIG. 3 is a cross-sectional view of an absorbent article using the surface material shown in FIG. 4 is an enlarged plan view of a breathable conveyor for manufacturing the second layer sheet according to this embodiment, and FIG. 5 is a side view of the breathable conveyor shown in FIG. 4. l; Sanitary napkin (absorbent article) 3; Surface material 7; First layer sheet 8; Second layer sheet 9; Recessed portion
10; Duct-shaped protrusion 12; Through hole Fig. 1 Fig. 2 Fig. 3

Claims (2)

[Claims] (1) A surface material for an absorbent article that has a first layer made of an aggregate of fibers located on the skin side of the human body and a second layer made of an aggregate of fibers located on the absorbent body side that absorbs excreta. The first layer is formed into a substantially planar sheet shape, the second layer is formed into a sheet shape having a large number of duct-like projections, and each of the duct-like projections has a A surface material for an absorbent article, characterized in that a hole is provided, a recess is formed around each of the duct-like protrusions, and the recesses are in communication. (2) The surface material for an absorbent article according to claim 1, wherein the constituent fibers of the second layer are fibers having a higher hydrophilicity than the constituent fibers of the first layer.