JP2859725B2 - Surface material of absorbent article and method of manufacturing the same - Google Patents

Description

The present invention relates to a surface material for absorbent articles such as sanitary napkins and diapers, and a method for producing the same.

[Conventional technology]

In general, absorbent articles such as sanitary napkins and diapers include an absorbent body that absorbs liquids such as blood and urine, a surface material that covers the surface of the absorbent body and is applied to the skin, and a liquid leakage that covers the back surface of the absorbent body. And a back surface material for preventing

The surface material of the absorbent article, in addition to the required fit at the time of mounting, blood, urine or other liquid is transferred to the absorber, liquid permeability for absorption by the absorber is required,
Further, a liquid return preventing property that does not return the liquid once absorbed by the absorber to the skin side is required.

Conventionally, in order to respond to the above demand, for example, an absorbent and a surface material made of a water-repellent nonwoven fabric are partially contacted with an adhesive or embossing so that a liquid such as blood or urine permeates the absorbent at the contact point. Absorbent articles (Japanese Patent Application Laid-Open
163137) and a plurality of grooves (grooves provided with strong capillary conduits) which are made of thin wadding mixed with absorbent fibers and which extend in the longitudinal direction and intersect with the edges and ends. Are formed at regular intervals so that blood, urine, and other liquids can penetrate into the absorber through the grooves (JP-A-53-8339).
No. 6) has been proposed.

[Problems to be solved by the invention]

However, in the former absorbent article described above, the liquid penetrates from the contact point between the absorber and the water-repellent surface material and is absorbed by the absorber. There was a disadvantage that the components were hardly absorbed by the absorber.

In addition, the latter absorbent article uses a surface material in which a groove formed by compressing a thin cotton wadding mixed with an absorbent fiber is formed by pressing, and a non-pressed portion between the grooves ( Since the cushion function of the convex portion is small, the convex portion may collapse due to pressure during use, and the liquid once absorbed may return to the skin side.

Therefore, an object of the present invention is to provide an absorbent article having a liquid permeability capable of absorbing even a highly viscous liquid, and having a liquid return preventing property in which the liquid once absorbed by the pressure during use does not return to the skin side. And a method of manufacturing the same.

[Means for solving the problem]

The present invention relates to a surface material made of a liquid-impermeable material that covers the surface of the absorbent body of the absorbent article provided with the absorbent body, wherein the surface material has a plurality of independent hollows extending along the longitudinal direction thereof. Surface of the absorbent article, wherein the convex ridges are arranged at appropriate intervals in the width direction of the surface material, and a plurality of liquid-permeation openings are formed between the hollow convex ridges, respectively. The above object has been achieved by providing a material.

It is preferable that the surface material is composed of an upper surface material having the hollow ridge formed thereon and a lower layer surface material adhered to the upper layer material so as to close the hollow ridge. In addition, it is preferable that a peripheral portion of the opening for liquid permeation is used by being bonded to the absorber.

The present invention is also a preferred method of manufacturing the surface material, and is a method of manufacturing a surface material of an absorbent article according to claim (2), wherein the liquid impermeable film is formed and processed. Forming the hollow ridges of the book at appropriate intervals in the width direction of the surface material, forming the upper surface material, and projecting the hollow ridges of the upper surface material formed in the forming step The lower surface material made of a liquid-impermeable film is bonded to the non-surface side to close the hollow ridge, a bonding step, and a plurality of liquid-permeation openings between the ridges. And a method for producing a surface material of an absorbent article, comprising a step of forming a hole.

[Action]

ADVANTAGE OF THE INVENTION According to the surface material of the absorbent article of this invention, a liquid transfers to an absorber from the opening provided between the hollow convex stripes, and has a liquid permeability which can absorb a highly viscous liquid by the absorber. In addition, the hollow ridges reduce the pressure acting on the absorbent article during use, and have a liquid return preventing property of preventing the liquid once absorbed from returning to the skin side from the opening.

〔Example〕

 Hereinafter, embodiments of the present invention will be described.

First, an embodiment of the surface material of the absorbent article of the present invention will be described with reference to the drawings.

1 to 3 show an embodiment of the surface material of the absorbent article of the present invention, and FIG. 1 shows the absorbent article provided with the surface material according to the present embodiment cut in approximately half. Perspective view, second
FIG. 3 is a partial perspective view of the surface material according to the present embodiment, partially cut away, and FIG. 3 is a partially enlarged cross-sectional view showing a bonding state between the surface material and the absorber.

The surface material 1 according to the present embodiment is, as shown in FIG.
A surface material made of a liquid-impermeable material that covers the surface of the absorbent body 2 of the absorbent article provided with the absorbent body 2, and a plurality of hollow ridges (hereinafter, referred to as “strips”) extending along the longitudinal direction of the surface material 1 Ridge)
3 are arranged at appropriate intervals in the width direction of the surface material 1, and a plurality of liquid-permeation openings (hereinafter, referred to as openings) 4 are formed between the protrusions 3.

The surface material 1 is located on the skin side, the upper layer surface material 1a formed of a liquid impermeable film (water-repellent resin film) on which the ridges 3 are formed, and located on the absorber 2 side, And a lower layer surface material 1b, which is also made of a liquid impermeable film (water-repellent resin film) and is superimposed on and bonded to the upper layer surface material 1a. As the water-repellent resin film to be the upper layer surface material 1a, for example, low-density polyethylene (L
-LDPE, LDPE) film, polypropylene (PP) film, polyethylene terephthalate (PET) film, and resin films equivalent to these synthetic resin films. The thickness of these water-repellent resin films is 10μ
It is preferably from m to 30 μm. The lower surface material 1b
Examples of the water-repellent resin film include low-density polyethylene (L-LDPE, LDPE). The thickness of the water-repellent resin film is preferably 10 μm to 30 μm as in the case of the water-repellent resin film forming the upper layer surface material 1a. Further, as the adhesive 1c for bonding the upper layer surface material 1a and the lower layer surface material 1b, it is preferable to use a hot melt type adhesive having a melting temperature in a range of 100 ° C to 140 ° C.

Note that the surface material 1 is preferably opaque so as to cover the liquid or the like absorbed by the absorber 2.

As shown in FIG. 2, the ridge 3 has a substantially circular cross section and is formed by molding a water-repellent resin film serving as the upper layer surface material 1a. It is closed by the surface material 1b, is independent of each other, and has a cushion function (pressure relief function). This ridge 3
Is preferably sealed at normal pressure (preferably the internal air pressure is normal pressure). The diameter of the ridges 3 is preferably set to 2 mm to 5 mm, and the interval between the ridges 3 is preferably set to 4 mm to 7 mm.

The opening 4 is substantially circular and has a bottom surface portion of a space surrounded by the ridges 3, that is, the upper surface material 1a and the lower surface material.
1b are formed regularly or irregularly along the longitudinal direction of the surface material 1 at the portion where they overlap and adhere, and guide menstrual blood and the like to the absorber 2. Open area of the opening 4 is preferably set to 0.25 mm ² to 10 mm ^2, also the spacing between the apertures 4, 1 mm to 5 mm, especially 2mm~3mm
It is preferable to set

As shown in FIG. 3, the periphery of the opening 4 of the lower surface material 1b is adhered to the absorber 2 with an adhesive 1d made of hot melt type glue or the like.

In addition, on the back surface of the absorber 2, a back material 5 that covers the back surface and prevents liquid leakage is disposed.

 Next, the operation of the surface material 1 of the present embodiment will be described.

When the absorbent article provided with the surface material 1 is mounted, menstrual blood and the like are once collected between the ridges 3 and then absorbed by the absorber 2 through the openings 4. The cushioning function provides good adhesion to the skin and prevents the absorbent article from being deformed. In addition, the height difference between the upper end surface of the ridge 3 in contact with the skin and the bottom surface where the opening 4 is formed is provided. In addition, menstrual blood and the like easily fall toward the absorber 2, and the surface material 1 exhibits excellent liquid permeability. In particular, surface material 1 (lower layer surface material 1b)
Since the periphery of the opening 4 is bonded to the absorber 2 with the adhesive 1d, even the high-viscosity menstrual blood component discharged during menstruation is quickly absorbed by the absorber 2.

Further, in a use condition in which pressure acts on the absorbent article, the ridge 3 relieves the pressure by an air cushion function, and is slightly deformed to be surrounded by the ridge 3 (a space having an opening 4 on the bottom surface). ) In the shape of a pot or bag (drawstring)
Therefore, there is no possibility that menstrual blood or the like once absorbed will return to the skin side, and the surface material 1 exhibits excellent liquid return prevention properties.

Further, the space surrounded by the ridges 3 extends in the longitudinal direction of the surface material 1 (longitudinal direction of the absorbent article), and menstrual blood and the like that has fallen into the space flows in the longitudinal direction of the absorbent article and is absorbed. It will be absorbed by the body 2. In other words, since the absorber 2 can absorb menstrual blood and the like in the entire longitudinal direction, it is effectively used.

Next, an experimental example of the liquid (menstrual) return performance of the surface material 1 of the above embodiment will be described.

A pseudo-absorber, a liquid-return grasping absorber, and a test piece having the following dimensions were prepared.

Pseudo absorber; common absorbent paper; 65 mm width × 160 mm length; 20 sheets (weight: 7.0 ± 0.2 g) fluid return grasp absorbent body; filter paper; 80 mm width × 190 mm length; 10 sheets (weight: W ₁₎ Test piece: Non-woven fabric surface material; Film surface material; Mesh surface material; Surface material of this example; 170 mm width x 220 mm length; Five sheets each (measuring blood) The measurement of the return amount was performed as follows.

The pseudo-absorbent material is wrapped with a test piece (use side is outside), and placed on an acrylic plate so that the side where the test piece does not overlap faces upward.

The injection cell for liquid return measurement is placed on the test piece, and a weight is placed thereon so that a pressure of 5 kg / cm ² is applied to the absorber area of the test piece.

Immediately put 10 g of suspect blood into the infusion cell for liquid return measurement,
The moment when the suspicious blood reaches the test piece is defined as 0 second.

After 4:00 seconds, the injection cell for liquid return measurement and the weight are removed.

After 4 minutes and 30 seconds, ten filter papers are gently placed on the test piece.

After 4 minutes and 50 seconds, 50 kg / cm ²
Place the weight so that the pressure is applied.

After 3 minutes from the moment when the pressure of 50 kg / cm ² is applied, the weight is removed and the weight W _{2 of} ten filter papers is measured.

The change in weight of the filter paper (ΔW = W ₁ −W ₂ g) is defined as the liquid return amount of the test piece.

Five test pieces (nonwoven fabric surface material, film surface material, mesh surface material, surface material of this example) were measured, and the average value was taken as the value of the normal liquid return amount of the test piece.

 From the above measurements, the results shown in the following table were obtained.

As is clear from the above table, the surface material 1 of this example has a liquid (menstrual) return amount that is 1/8 that of the surface material (film surface material) having the smallest return amount in the comparative example. there were.

Next, an embodiment of a method of manufacturing the surface material 1 will be described with reference to the drawings.

4 to 7 show an embodiment of the method for manufacturing a surface material according to the present invention. FIG. 4 is an explanatory view schematically showing an entire manufacturing apparatus for performing the manufacturing method of the present embodiment. FIG. 6 is a partially enlarged sectional view for explaining a forming step, FIG. 6 is a partially enlarged sectional view for explaining a bonding step, and FIG. 7 is a partially enlarged sectional view for explaining a punching step.

As shown in FIG. 4, the manufacturing apparatus for carrying out the manufacturing method of this embodiment includes an upper surface material forming process section 11,
A forming drum 10 which sequentially moves (rotates) to the bonding step section 12, the perforating step section 13, and the discharging step section 14 and returns to the upper layer surface material forming step section 11 again; A film supply drum 15 for supplying a water-repellent resin film to be the material 1a, and an adhesive 1c disposed upstream of the bonding step section 12;
Adhesive application roll 16 for applying, a film supply drum 17 for supplying a water-repellent resin film serving as the lower surface material 1b to an intermediate portion of the bonding step section 12, disposed downstream of the bonding step section 12, A pressure roll 18 for pressing and adhering a water-repellent resin film serving as a lower surface material 1b to the upper surface material 1a, and a perforation having a cutting blade 19a arranged in the perforation process section 13 and forming the perforation 4. A roll 19 is provided.

On the outer peripheral surface of the forming drum 10, a plurality of grooves 10a extending in the axial direction for forming the ridges 3 are formed at appropriate intervals in the circumferential direction, and on the bottom surface of each groove 10a, A small hole 10b for vacuum suction is formed on the inner surface of the concave groove 10a for adhering a water-repellent resin film to be the upper layer surface material 1a. The forming drum 10 is preferably formed of a steel material having a hardened outer peripheral surface. The outer diameter of the forming drum 10 is 500 mm, the width is 300 mm, and the hardness of the peripheral surface is HR.
It is preferable to set each to C62 °. Preferably, the depth of the concave groove 10a is set to 3 mm, the groove width is set to 3 mm, and the groove pitch is set to 6 mm. Although not shown, the small hole
10b is connected to a vacuum pump.

The applied thickness of the adhesive 1c applied to the upper layer surface material 1a by the adhesive applying roll 16 is preferably set to 20 μm to 30 μm.

The punching roll 19 rotates at the same processing speed as the forming drum 10, and is preferably formed of a steel material whose outer peripheral surface is hardened to a hardness of about HRC 60 °. Also,
The cutting blades 19a are used to process the round holes 4 having a diameter of 2.0 mm, and are arranged on the outer peripheral surface of the punching roll 19 at appropriate intervals in the axial direction and at appropriate intervals in the circumferential direction. It is arranged in. The circumferential interval of the cutting edge 19a is preferably set to 6 mm in accordance with the pitch of the concave groove 10a, and the axial interval of the cutting edge 19a is adjusted to the interval of the opening 4, for example. Preferably, it is set to 3 mm.

Although not shown, in the discharge step section 14, the vacuum suction is released, and pressurized air is supplied from the small hole 10b to the concave groove 10a.
A device for blowing into the inside is arranged. The pressure of the pressurized air is preferably set to 2 / kgcm ^{2 to} 3 / kgcm ² .

In order to manufacture the surface material 1 using the above-described manufacturing apparatus, first, a water-repellent resin film serving as the upper surface material 1a is supplied from the film supply drum 15 to the upper surface material forming step section 11, and as shown in FIG. Then, the water-repellent resin film is wound around the outer peripheral surface of the forming drum 10 by the guide roll 20, and is brought into close contact with the inner surface of the concave groove 10a by the vacuum suction force from the small hole 10b to form the ridge 3 (the upper surface material 1a is formed). Molding).

Next, the forming drum 10 is rotated clockwise in FIG. 3, and the upper surface material 1a on which the ridges 3 are formed is transported to the upstream side of the bonding section 12 where the adhesive coating roll is applied.
The adhesive 1c is applied with a thickness of 20 μm to 30 μm by 16 and then conveyed to an intermediate portion of the bonding process section 12, where the lower surface material 1b conveyed from the film supply drum 17 at the intermediate portion as shown in FIG. The water-repellent resin film to be joined is joined to the upper surface material 1a by the guide roll 21, and thereafter, the pressure is applied by the pressure roll 18 on the downstream side of the bonding section 12 to be bonded.

Next, the forming drum 10 is rotated clockwise in FIG. 3, and the upper layer surface material 1a and the lower layer surface material 1b are conveyed to the hole forming step section 13, and as shown in FIG. At 13, an opening 4 is formed in a portion between the ridges 3 by a hole forming roll 19.

Next, the forming drum 10 is rotated clockwise in FIG. 3, and the ridges 3 are separated from the grooves 10a in the discharge step section 14 by using pressurized air.

When the surface material 1 is manufactured as described above, the manufacturing efficiency is good, and the product yield can be improved.

The surface material 1 manufactured as described above is covered on the front side of the absorber 2 manufactured in a separate process, and merges with the back material 5 supplied from the back material supply drum 22. . Thereafter, the semi-finished product in which the absorbent body 2 is interposed between the front surface material 1 and the back surface material 5 is a seal for sealing both ends in the longitudinal direction of the absorbent article, which is a general process of processing the outer packaging material of the absorbent article. It is sequentially conveyed to a process, a tape attaching process of attaching an adhesive tape for fixing to shorts, an outer package cutting process, and the like. Thus, an absorbent article is manufactured.

In the above embodiment, the case where the surface material 1 is constituted by bonding the upper layer surface material 1a and the lower layer surface material 1b is shown, but may be constituted by a single film. In this case, the opening edges of the openings 3a of the ridges 3 may be adhered to each other and closed.

Further, the case where the hollow ridge 3 has a substantially circular cross section is shown, but the present invention is not limited to this, and the ridge 3 may be formed to have a substantially elliptical cross section.

Also, the case where the opening 4 is formed in a substantially circular shape is shown,
The invention is not limited to this, and may be formed in a square shape, an elliptical shape, or the like.

〔The invention's effect〕

ADVANTAGE OF THE INVENTION According to the surface material of the absorbent article of this invention, it has the liquid permeability which can also absorb a highly viscous liquid, and the liquid return prevention property which has no danger that the liquid once absorbed by the pressure at the time of use will return to the skin side. Having. Further, the hollow ridge can prevent lateral leakage, and can also absorb menstrual blood and the like in the entire longitudinal direction of the absorber, so that the entire absorber can be used effectively. Further, according to the method for producing a surface material of an absorbent article of the present invention, a surface material having the above-described effects can be efficiently produced.

[Brief description of the drawings]

1 to 3 show an embodiment of the surface material of the absorbent article of the present invention, and FIG. 1 shows the absorbent article provided with the surface material according to the present embodiment cut in approximately half. FIG. 2 is a partial perspective view of the surface material according to the present embodiment, with a part cut away, FIG. 3 is a partially enlarged cross-sectional view showing a bonding state between the surface material and the absorber, and FIG. FIG. 7 to FIG. 7 show an embodiment of the method for manufacturing a surface material according to the present invention, FIG. 4 is an explanatory view schematically showing an entire manufacturing apparatus for performing the manufacturing method of the present embodiment,
FIG. 5 is a partially enlarged cross-sectional view illustrating a molding step, and FIG.
FIG. 7 is a partially enlarged sectional view for explaining the bonding step, and FIG. 7 is a partially enlarged sectional view for explaining the hole making step. 1; Surface material, 1a; Upper layer surface material 1b; Lower layer surface material, 2; Absorber 3; Convex ridge, 4; Opening 10; Forming drum 11; Convex ridge forming process section 12; Bonding process section 13; Drilling Process section

Claims (4)

(57) [Claims] 1. A surface material made of a liquid-impermeable material for covering the surface of an absorbent body of an absorbent article provided with the absorbent body, wherein the surface material has a plurality of independent members extending along the longitudinal direction thereof. Hollow ridges are arranged at appropriate intervals in the width direction of the surface material, and a plurality of liquid-permeation openings are formed between the hollow ridges, respectively. Surface material. 2. The method according to claim 1, wherein the surface material comprises an upper surface material having the hollow ridge formed thereon and a lower surface material adhered to the upper surface material so as to close the hollow ridge. The surface material of the absorbent article according to claim 1, wherein 3. The liquid absorbing device according to claim 1, wherein a peripheral portion of the liquid permeation hole is used by being adhered to the absorber.
A surface material of the absorbent article according to the above. 4. The method for producing a surface material of an absorbent article according to claim 2, wherein said plurality of hollow ridges are formed in a width direction of said surface material by forming and processing a liquid impermeable film. Formed at appropriate intervals, forming the upper layer surface material, and forming a liquid impermeable film on the surface of the upper layer surface material formed in the molding step on the side where the hollow ridge does not protrude. A bonding step of bonding the lower surface material so as to close the hollow ridge, and a hole forming step of forming a plurality of liquid permeation holes between the ridges. A method for producing a surface material of an absorbent article.