JPH0572828B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a porous liquid absorbent sheet and a method for manufacturing the same. More specifically, the present invention relates to a porous liquid-absorbing sheet used as a skin-facing sheet in body fluid absorbing devices such as sanitary napkins, breast milk pads, hemorrhoid pads, panty liners, and incontinence pads, and a method for producing the same.

[Conventional technology]

The skin-facing sheet in conventional body fluid absorbers is 1
Liquid-absorbing sheets were used in which cuts or holes were formed by embossing or other methods on a sheet of film. Then, sanitary napkins and the like were constructed by covering an absorbent layer such as cotton-like pulp with such a skin-contacting sheet and applying a waterproof sheet to the back side of the absorbent layer.

[Problem to be solved by the invention]

However, conventional liquid-absorbing sheets have a problem in that absorbed body fluids accumulate directly on the back side of the sheet, giving the skin a moist feeling and not being pleasant to the touch. In addition, since the opening areas of the cuts and holes are virtually the same on the skin-facing side of the liquid-absorbing sheet and on the absorbent layer side,
There was a problem in that it was difficult to prevent the backflow of absorbed body fluids.

In view of these circumstances, the present invention provides a liquid-absorbing sheet that provides a smooth texture, prevents the backflow of absorbed body fluids, and prevents the sheet from losing its shape to maintain a good texture for a long time. The purpose is to provide.

Another object of the present invention is to provide a manufacturing method that can efficiently manufacture the liquid absorbent sheet.

[Means for Solving the Problems] The liquid absorbent sheet of the present invention is composed of a front side film and a back side film, and a large number of tapered protrusions are formed on the front side film, and a number of tapered protrusions are formed on the bottom end of the tapered protrusions. The back film is adhered to the tapered protrusion, and a tapered hole passes through the tapered projection from the front film to the back film, and the portion that is not the tapered hole is sealed by the front film and the back film. It is characterized by forming an air chamber.

Furthermore, the method for producing a porous liquid-absorbing sheet according to the present invention involves supplying a heated synthetic resin film to the surface of an embossing roll, applying negative pressure from the inner surface of the embossing roll, and applying pressure from above the film. The film is pressed to form a large number of tapered protrusions, another synthetic resin film is superimposed on the film and heat sealed, and then the bottom end of the tapered protrusions is cut off.

[Effect]

The liquid-absorbing sheet of the present invention is bulky due to the tapered protrusion, and also has air chambers and a dry area within the sheet itself, so it does not give a moist feeling to the skin. do not have. Therefore, a smooth and good feeling of use can be obtained. Since the air chamber works to maintain the original shape of the seat against external forces, it will not lose its shape even if body pressure increases during use. Therefore, good texture can be maintained for a long time.

Next, the tapered hole in the present invention speeds up the absorption of body fluid from the surface side, and functions as a check valve to prevent the absorbed body fluid from returning to the surface side. Therefore, body fluids do not leak to the surface side, and from this point of view as well, a good texture can be guaranteed.

In the manufacturing method of the present invention, a tapered protrusion is embossed while a synthetic resin film is placed on the surface of an embossing roll and rotated, and then a second film is heat-sealed to form tapered holes. Ru. The process is performed as the embossing roll rotates, and there is no need to change the process, so it is suitable for continuous production. Therefore, the porous liquid absorbent sheet can be supplied at low cost.

〔Example〕

Next, embodiments of the present invention will be described based on the drawings.

1 and 2 show a porous liquid absorbent sheet S which is an embodiment of the present invention. In the same figure,
1 is a front side film, and 2 is a back side film. A large number of tapered projections 3 are formed in a mesh shape on the front side film 1 by embossing described later, and the back side film 2 is adhered to the bottom end of the tapered projections 3 by heat sealing or the like. .

The inner surface of the tapered protrusion 3 is a tapered hole 4 passing through it, and the diameter of the tapered hole 4 on the front side is large and the diameter on the back side is small. The portion other than the tapered hole 4 is surrounded by the front side film 1 and the back side film 2 and is a sealed space, forming an air chamber 5. In this embodiment, the air chamber 5 exists around the tapered hole 4 as shown in the figure.

Next, the effect when the liquid-absorbing sheet 1 of the above embodiment is applied to the skin-facing sheet of a body fluid absorbing device such as a sanitary napkin or a breast milk pad will be explained.

In FIG. 2, the upper surface of the liquid absorbent sheet S faces the human body, and the absorbent layer 6, such as linear pulp or absorbent paper, is located on the lower surface.

When body fluid is absorbed, the body fluid flows into the tapered hole 4 from the larger opening area (arrow a), so that the absorption speed becomes faster. Once the body fluid has been absorbed into the absorbent layer 6, the opening area of the tapered hole 4 becomes smaller, so that the body fluid accumulates inside without flowing back, as shown by arrow b. Therefore, the liquid-absorbing sheet S of this embodiment can achieve both a high liquid-absorbing speed and prevention of backflow, which are difficult to achieve at the same time.

In the case of the liquid absorbent sheet S of this embodiment, the human skin and the absorbent layer 6 are separated by the bulky liquid absorbent sheet S. Since it is always dry without being moist, it can give the human body a dry and smooth feeling when using it.

Moreover, since the air chamber 5 does not collapse even when an external force is applied, the shape of the liquid-absorbing sheet S and the shape of the tapered hole 4 do not change. Therefore, the functions performed by the taper holes 4 and the air chambers 5 can be maintained for a long time, and a good texture can be guaranteed for a long time.

Since the liquid-absorbing sheet of the present invention has the above characteristics, it can be used in sanitary napkins, breast milk pads, hemorrhoid pads, etc.
It is suitable for use in body fluid absorbing devices such as panty liners and incontinence pads.

Next, a method for manufacturing a liquid absorbent sheet according to the present invention will be explained.

FIG. 3 shows an example of an apparatus used in the manufacturing method of the present invention. Reference numeral 11 denotes an embossing roll, and a large number of tapered protrusions 12 are formed on the outer peripheral surface of the roll, as shown in FIG.
Further, a large number of intake and exhaust holes 14 are formed in the roll cylinder 13. The internal cavity of the embossing roll 11 is partitioned by a partition wall 15 into an intake chamber 16 on the right side and an exhaust chamber 17 on the left side. and intake chamber 1
6 is communicated with the suction side of the vacuum pump through a passage 18, and the exhaust chamber 17 is communicated with the exhaust side of the vacuum pump through a passage 19. Therefore, while the embossing roll 11 is rotating, air is sucked in from the intake and exhaust holes 14 in the region facing the intake chamber 16, and air is blown out from the intake and exhaust holes 14 in the region facing the exhaust chamber 17. ing.

A thermal spraying device 21 for thermally spraying a thermoplastic resin such as polyethylene or polypropylene into a film is disposed above the embossing roll 11 on the left side. Then, along the rotation direction of the roll 11, a pressure roller 22, a cooler 23, and a second thermal spraying device 2 are installed.
4. The heat sealing roll 25 and the perforating roll 26 are
They are arranged in that order. The cooler 23 has a structure that blows cold air onto the film. The perforation roll 26 has a built-in appropriate heater, and a felt roll 27 for applying silicone oil as a mold release agent is attached.

When the film to be the front side film 1 is thermally sprayed from the first thermal spraying device 21, it passes under the pressure roller 22 as the embossing roll 11 rotates, and is cooled by the cooler 23. During this time, negative pressure is applied to the film 1 by the intake hole 14,
Further, by being pressed by the pressure roller 22,
A large number of tapered protrusions 3 are formed in close contact with the tapered protrusions 12. This shape is then fixed by cooling.

Next, a film to be the back side film 2 is thermally sprayed from the second thermal spraying device 24 and placed on top of the previously formed front side film 2. Then, when passing under the heat sealing roller 25, the bottom end of the tapered projection 3 and the back side film 2 are heat sealed.

Then, each bottom end of the protrusion 3 is cut by melting or scraping with a perforation roll 26, thereby forming a porous liquid-absorbing sheet S having tapered holes 4 perforated therein. In addition, the hole punching roll 26
Since the film is coated with silicone oil, the cut part will not get stuck to the film.

Next, a manufacturing method using another manufacturing apparatus will be explained based on FIG.

In the figure, 31 is an embossing roll;
The internal cavity is partitioned into an intake chamber 33 by a partition wall 32 . The suction chamber 33 is communicated with a vacuum pump or the like through a passage 34, and, like the embossing roll 11, air can be sucked through the suction hole formed in the roll body. Embossing roll 31
From the left side in the figure, along the rotation direction, there are a guide roller 35, a heater 36, a pressure roll 37, a cooler 38, a heat sealing roll 41, and a punching rotor 4.
2 are provided in that order.

This device does not thermally spray a synthetic resin as a raw material to form a film, but uses pre-manufactured film rolls 1a and 1b, so a heater 36 is required to heat the front film 1. . Note that the drilling rotor 42 is a propeller type with a built-in cartridge heater 43.
A punching roll 26 shown in FIG. 3 may also be used.

When using this device, the front side film 1 is heated by a heater 36 and then pressed by a pressure roller 37 to form a large number of tapered protrusions 3. Then, the shape is fixed by receiving cold air from the cooler 38.

Next, the back side film 2 is moved to the guide roller 39
The film is guided by the film 1 and placed on the front film 1, and heat-sealed by the heat-sealing roller 41. As a result, the bottom end of the tapered protrusion 3 and the back side film 2 are bonded together.

Then, each bottom end of the tapered protrusion 3 is melted or scraped off by the drilling rotor 42 and cut so that the tapered hole 4 is formed.

Through the above steps, the porous liquid absorbent sheet S is formed.

The above-mentioned manufacturing methods of this example are all carried out based on the rotation of embossing rolls, and there is no need to change the process midway, so that the porous liquid-absorbent sheet of the present invention can be efficiently manufactured.

〔Effect of the invention〕

The porous liquid-absorbent sheet of the present invention has a good texture and does not lose its shape, so it can maintain a good feeling of use for a long time. In addition, it absorbs body fluids quickly and prevents the reflux of absorbed body fluids.
Do not moisten the skin.

According to the manufacturing method of the present invention, the porous liquid-absorbing sheet can be manufactured efficiently and at high speed.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a porous liquid-absorbent sheet according to an embodiment of the present invention, FIG. 2 is a sectional view of the sheet, FIG. 3 is a schematic diagram of a manufacturing apparatus used in the manufacturing method of the present invention, and FIG. The figure is a partially enlarged view of the embossing roll, and FIG. 5 is a schematic diagram of another manufacturing apparatus used in the manufacturing method of the present invention. (Main symbols in the drawing), S: porous liquid absorbent sheet,
1: Front side film, 2: Back side film, 3:
Tapered protrusion, 4: Tapered hole, 5: Air chamber, 1
1, 31: embossing roll, 22, 37: pressure roller, 23, 38: cooler, 25, 41: heat sealing roller, 26: punching roller, 42: punching rotor.

Claims (1)

[Claims] 1. Consisting of a front side film and a back side film, the front side film has a large number of tapered protrusions formed therein, and the back side film is adhered to the bottom end of the tapered protrusions. In the tapered protrusion, a tapered hole penetrates from the front side film to the back side film, and the portion that is not the tapered hole forms an air chamber sealed by the front side film and the back side film. A porous liquid-absorbing sheet that is characterized by: 2. Supplying a heated synthetic resin film to the surface of an embossing roll, applying negative pressure from the inner surface of the embossing roll, and applying pressure from above the film to form a large number of tapered protrusions on the film. . A method for manufacturing a porous liquid-absorbing sheet, comprising: superimposing another synthetic resin film on the film and heat-sealing the film, and then cutting the bottom end of the tapered protrusion.