JP3732320B2 - Disposable liquid absorbent article - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a disposable liquid absorbent article suitable for use as a disposable diaper, a sanitary napkin, a panty liner, a urine absorbing pad, a blood absorbing pad and the like.
[0002]
[Prior art]
The sheet absorber disclosed in JP-A-6-90977 is composed of a liquid-impervious elastic sheet, a liquid-permeable nonwoven fabric, and an absorbent material. The elastic sheet and the nonwoven fabric are joined in a plurality of bands extending in parallel. Between adjacent bands, a channel is formed by making the width of the nonwoven fabric larger than that of the elastic sheet. Each of the channels contains an absorbent material containing a water-absorbing polymer. Since such a sheet absorbent is used for diapers and sanitary napkins with the nonwoven fabric in contact with the skin, the water-absorbing polymer that has absorbed the body fluid swells to fill the voids in the channel, and further the elastic sheet To expand the channel.
[0003]
[Problems to be solved by the invention]
In the conventional absorbent body, when the water-absorbing polymer swells and the absorbent is filled in each channel, the side of the wide nonwoven fabric swells and forms wrinkles before the elastic sheet is stretched. The top part comes into contact with the wearer's skin. In such a sheet absorber, the rigidity of the channel filled with the absorbent material is increased, and the skin may be strongly pressed locally at the top of the heel to cause discomfort.
[0004]
Therefore, in the present invention, it is an object to provide a disposable liquid-absorbent article that is unlikely to be locally compressed as in the prior art.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the present invention presupposes that an absorbent material is provided between a liquid-permeable surface sheet positioned on the skin contact side and a liquid-impermeable back sheet positioned on the skin non-contact side. It is a disposable liquid-absorbent article formed by intervening.
[0006]
In this premise, the present invention is characterized in that the top sheet is formed from a substantially non-stretchable sheet, the back sheet is formed from a sheet that is elastically stretchable by 50% or more, and the back surface 50% elongation stress of the sheet is 50% or less of the tensile rupture stress of the surface sheet. In the article, an intermediate sheet having higher hydrophilicity than the surface sheet is in contact with the inner surface of the surface sheet, The back sheet and the intermediate sheet are joined in a plurality of bands extending in parallel with each other, and between the adjacent two bands, the inter- zone dimension between the top sheet and the intermediate sheet is in the range of 2 to 7 mm. to have, by the inter-band size of the backsheet to 1.2 to 3.0 times the bandwidth between the dimensions of the intermediate sheet and said topsheet, it said and said topsheet intermediate The back sheet to form a plurality of tubular portion extending along said zone from the surface is curved in a direction toward the rear surface of the article and the over preparative be flat, the direction in which the intermediate sheet extends of said tubular portion The liquid-absorbing material having higher body fluid diffusibility than the top sheet and containing 5 to 98% by weight of highly water-absorbing polymer particles may be contained in the tubular portion.
[0007]
[0008]
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The details of the disposable liquid-absorbent article according to the present invention will be described with reference to the accompanying drawings.
[0010]
FIG. 1 is a partial view of a panty liner 1 which is an example of a liquid-absorbent article, and is partially broken.
[0011]
2 is a partial cross-sectional view taken along line II-II in FIG.
[0012]
1 and 2, the panty liner 1 includes a liquid-permeable top sheet 2 located on the skin contact side, a liquid-impervious back sheet 3 located on the skin non-contact side, and front and back sheets 2 and 3. It is comprised from the liquid absorption material 4 interposed in between. The topsheet 2 has an inner surface 6 and an outer surface 7 and is in a flat state. The back sheet 3 has an inner surface 8 and an outer surface 9, and has a corrugated structure by repeating undulations in the width direction of the panty liner 1 (left and right direction in the figure). The inner surface 6 of the top sheet 2 and the inner surface 8 at the top of the corrugation of the back sheet 3 are joined in a number of zones 11 extending in the front-rear direction of the panty liner 1. Between the adjacent two strips 11, the back sheet 3 is curved in the direction from the front surface to the back surface of the panty liner 1 by making the inter-band dimension of the back sheet 3 larger than the inter-band dimension of the top sheet 2. Thus, a large number of tubular portions 10 extending along the zone 11 are formed. In addition, the surface sheet 2 is flat. The tubular part 10 accommodates the liquid absorbing material 4. Adjacent zones 11 are parallel to each other with a required separation distance d ₁ , and the separation distance d ₁ is equal to the width (inter-zone dimension) of the topsheet 2 in the tubular portion 10. The width (inter-band dimension) of the back sheet 3 between the bands 11 is larger than d ₁ , and preferably 1.2 to 3.0 times d ₁ . The separation distance d ₁ is particularly preferably in the range of 2 to 7 mm when the liquid absorbent article is the illustrated panty liner 1. The width _{d 2} of the band 11 when the distance _{d 1} is such a value is preferably in the range of 0.1 to 3 mm.
[0013]
The liquid absorbing material 4 contains 5 to 98% by weight of the superabsorbent polymer particles and 95 to 2% by weight of pulverized pulp, hydrophobic thermoplastic synthetic fiber, and a mixture of pulverized pulp and thermoplastic synthetic fiber.
[0014]
The surface sheet 2 is made of a sheet material such as a nonwoven fabric or an open plastic film, and is substantially non-stretchable.
[0015]
The back sheet 3 is a sheet of rubber or elastomer that is elastically stretchable by 50% or more in at least the width direction of the panty liner 1, that is, the direction orthogonal to the extending direction of the band 11, and stretches when stretched by 50%. A material whose stress is 50% or less of the tensile breaking stress of the surface sheet 2 is used.
[0016]
An adhesive such as a hot melt adhesive can be used for joining the top sheet 2 and the back sheet 3 in the zone 11. Moreover, when at least one of these sheets 2 and 3 is a heat-meltable thing, a welding technique can also be utilized. Such techniques include ultrasonic welding techniques.
[0017]
In the panty liner 1 configured as described above, when the superabsorbent polymer swells due to the absorption of the body fluid and the liquid absorbing material 4 fills the tubular portion 10, the back sheet 3 having a relatively small elongation stress is shown in FIG. It expands like this. The top sheet 2 is a non-extensible material that does not substantially extend even when the back sheet 3 is extended, and maintains a flat state even when the superabsorbent polymer swells. There is almost no change in the contact state with the skin. The panty liner 1 accommodates the liquid absorbing material 4 so that it does not spill out of the tubular portion 10 by adhering or welding the front and back sheets 2 and 3 on the four sides thereof.
[0018]
In the panty liner 1, it can be combined a plurality of tubular portions 10 where the width d ₁ is different from a variety. For example, side by side and a small tubular portion 10 and the large tubular portion 10 having a width d ₁ alternately to form a group of a plurality of tubular portions 10 larger width d _1, more width d ₁ is smaller adjacent its group A group of tubular portions 10 can also be arranged.
[0019]
FIG. 3 is a view similar to FIG. 2 showing one embodiment of the present invention. In the panty liner 1, the intermediate sheet 16 is in contact with the inner surface of the top sheet 2. Between the adjacent two strips 11, by making the inter-band dimension of the back sheet 3 larger than the inter-band dimension of the top sheet 2 and the intermediate sheet 16, the back sheet 3 moves from the front surface of the panty liner 1 to the back surface. A large number of tubular portions 10 are formed that are curved in the direction of the direction and extend along the zone 11. The top sheet 2 and the intermediate sheet 16 are flat. The tubular part 10 accommodates the liquid absorbing material 4. The intermediate sheet 16 has higher hydrophilicity than the top sheet 2. The intermediate sheet 16 further has a diffusibility of the body fluid in the direction in which the zone 11 extends, that is, the direction in which the tubular portion 10 extends, and more preferably has a diffusibility higher than the diffusibility of the topsheet 2 in that direction. Due to the presence of the intermediate sheet 16, the body fluid on the outer surface 7 of the topsheet 2 quickly moves to the liquid absorbent material 4 or diffuses in the direction in which the tubular portion 10 extends and contacts the liquid absorbent material 4 over a wide range. It becomes possible to do. The intermediate sheet 16 in the illustrated example is bonded to the front and back sheets 2 and 3 via a hot melt adhesive in the zone 11. The intermediate sheet 16 may be joined to the top sheet 2 between the adjacent zones 11.
[0020]
The liquid absorbent article according to the present invention can be used not only as a panty liner 1, but also as a disposable diaper, a sanitary napkin, a panty liner, a urine absorbing pad, and a blood absorbing pad.
[0021]
【The invention's effect】
In the disposable liquid-absorbing article according to the present invention, when the liquid-absorbing material containing the superabsorbent polymer swells when it is used in contact with the skin, the elastic stretchability that does not contact the skin Since the back sheet is stretched and the top sheet in contact with the skin maintains a flat state, the article may locally press the wearer's skin due to swelling of the superabsorbent polymer. Absent.
[0022]
In an article in which a highly hydrophilic intermediate sheet is bonded to the inner surface of the top sheet, it is possible to quickly transfer a liquid such as a body fluid on the outer surface of the top sheet to the liquid absorbing material. If this highly hydrophilic intermediate sheet is liquid diffusive, it becomes easy to absorb body fluid and the like with a wide range of liquid absorbing material in the tubular portion, and the liquid absorbing speed of the article is improved.
[Brief description of the drawings]
FIG. 1 is a partial view showing a part of a liquid-absorbent article (panty liner) in a cutaway manner.
2 is a cross-sectional view taken along line II-II in FIG.
FIG. 3 is a drawing similar to FIG. 2 showing an example of an embodiment.
[Explanation of symbols]
1 Liquid absorbent article (panty liner)
2 Liquid-permeable surface sheet 3 Liquid-impermeable back sheet 4 Liquid-absorbing material 6 Inner surface 10 Tubular portion 11 Zone 16 Intermediate sheet

Claims (1)

A disposable liquid-absorbent article in which an absorbent material is interposed between a liquid-permeable surface sheet positioned on the skin contact side and a liquid-impermeable back sheet positioned on the skin non-contact side,
The top sheet is formed from a substantially non-stretchable sheet, the back sheet is formed from a sheet that can be elastically stretched by 50% or more, and the back sheet is subjected to 50% elongation stress by pulling the top sheet. 50% or less of the breaking stress,
In the article, an intermediate sheet having higher hydrophilicity than the surface sheet contacts the inner surface of the surface sheet, and the front and back sheets and the intermediate sheet are joined in a plurality of strips extending in parallel with each other,
Between the adjacent bands of the two strips, the inter-zone dimension between the top sheet and the intermediate sheet is in the range of 2 to 7 mm, and the inter-zone dimension of the back sheet is set to the zone between the top sheet and the intermediate sheet. By making it 1.2 to 3.0 times the inter-dimensional dimension, the top sheet and the intermediate sheet are flat, and the back sheet is curved in the direction from the front surface to the back surface of the article, along the band. The intermediate sheet has a higher body fluid diffusibility than the top sheet in the extending direction of the tubular part, and the tubular part contains 5 to 98% by weight of superabsorbent polymer particles. The article, wherein the liquid absorbing material is accommodated.

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