JP3179323B2 - Method of manufacturing disposable diapers - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for manufacturing a disposable diaper. More particularly, the present invention relates to a method for producing a disposable diaper having improved resistance to unevenness and leakage.

[0002]

2. Description of the Related Art Conventionally, a disposable diaper has an absorber sandwiched between a top sheet and a back sheet, has side flaps extending outward from both longitudinal side edges of the absorber, and has elasticity in the side flaps. An elastic body is attached to improve the fit to the crotch and prevent leakage. In addition, by providing a second flap extending upwardly from the side flap or the top sheet and forming the second flap with a breathable water-repellent nonwoven fabric, air permeability is imparted and unevenness is reduced. There is a disposable diaper designed for.

That is, as disclosed in Japanese Patent Application Laid-Open No. 62-250201, there is provided a second flap having a side flap containing a stretchable elastic body and falling inside a diaper as a leak-proof portion.
A diaper in which a flap is provided and a pocket portion is formed between the diaper and a surface sheet on an absorber to prevent leakage has been known.

Further, as shown in Japanese Patent Application Laid-Open No. 62-223303, an elastic body is not provided on the side flap, but is provided on the leak-proof part (second flap part). A diaper is known in which the second flap is tilted outward in the back region and is adhesively fixed to improve the unevenness.

Further, as shown in Japanese Utility Model Application Laid-open No. Sho 62-153311, an elastic body is not provided on the side flap, but an elastic body is provided on the leak-proof portion (second flap portion), and the abdominal region is provided. And in the back area, the second flap is turned inward in the diaper, and is adhesively fixed to the side flap.
Diapers with improved leakage are known.

[0006] In all conventional disposable diapers having a second flap, the base end of the second flap is located on the outer side of both side edges of the absorbent body, and there is no absorbent directly under the second flap, and the portion thereof is not provided. When urine flows out, a pool is formed in that part, and leakage easily occurs through the second flap or jumps over the elastic elastic body at the top of the second flap.

[0007]

In a conventional disposable diaper having improved leakage and leakage, the second flap, which is a leak-proof portion, is made of a material having air permeability although it is water repellent. Prevention was not complete. An object of the present invention is to solve such a problem.

[0008]

SUMMARY OF THE INVENTION The present inventors have conducted intensive studies to further improve the above-mentioned problems, that is, to further improve the leakage of disposable diapers having a second flap in order to improve the unevenness and leakage. Invented the invention. That is, a liquid-permeable top sheet and a liquid-impermeable back sheet, having an absorber therebetween, and having side flaps extending outward from both lateral edges of the absorber, the side flap area In a disposable diaper having a second flap placed on top thereof and having an elastic elastic body in the second flap, the second flap has both sides of the topsheet with the elastic elastic body inward. It is configured by folding so as to wrap around, the side flaps, the back sheet,
A film or sheet-like material that is separate from the topsheet is bonded to the topsheet, and the second flap has its base end placed on the topsheet inside the side edges of the absorber. Have found that the above problem can be solved.

That is, according to the method of the present invention, the front side sheet 1 whose both side edges are bent so as to wrap the elastic elastic body 4 inside is bonded to the back side sheet 3 and the absorber 2 before the both side edges are bonded. Is formed as a separate film from the topsheet formed by folding the elastic body 4 so as to wrap the elastic body 4 inside and forming the second flap 6 and the topsheet forming the side flaps 7 along the base of the second flap. A liquid-permeable top sheet 1, a liquid-impermeable back sheet 3, and an absorber 2 between them, characterized in that joining with the sheet-like material 8 is performed in advance, It has side flaps 7 extending outward from both side edges, and has second flaps 6 installed along both side edges of the absorber. The side flaps are separate from the back sheet and the top sheet. Film or sheet element of body And the second flap has a base end on a surface sheet 1 to 30 mm inside from both side edge positions on the absorber, and is a method of manufacturing a disposable diaper that stands upright. is there.

Furthermore, both side edges of the topsheet, that is, the portion forming the second flap, are water-repellent, and the central region of the topsheet, ie, the portion located in the region above the absorber, is hydrophilic. It has been found that leakage can be further improved by using a material. In addition, it has been found that leakage can be further improved by attaching a waterproof thin film such as a microporous polyester film along the inside of the second flap.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
As the top sheet, back sheet, absorber and the like used in the present invention, non-woven fabric, polyethylene sheet, fluff pulp + high-absorbency polymer and the like used in ordinary diapers can be used as they are. However, a surface sheet having both sides subjected to a water-repellent treatment is also used. Further, the side flap is formed by bonding a hydrophilic or water-repellent nonwoven fabric, a breathable polyethylene film, or the like to a portion of the back sheet extending outward from both side edges of the absorber.

As the elastic elastic body installed in the second flap and the side flaps, urethane films, urethane foams, urethane thread rubbers, natural rubbers, and the like are used. Also, in the side flaps, the elastic elastic body may or may not be installed, but when the elastic elastic body is installed in the side flaps, the anti-shearing property is slightly deteriorated, but the leakage prevention is improved. On the other hand, when not installed, the leakage prevention is slightly inferior, but the unevenness prevention is good. When the second flap is folded outward, if the second flap is formed on both sides of the top sheet, the number of bonding steps is one less than when a material separate from the top sheet is used, and the second flap is formed of the same material as the side flap. The number of folding steps is reduced by one.

The position for attaching the second flap is as follows:
A position 1-30 mm inside from the side edge of the absorber is appropriate. At a position of 1 mm or less, a urine pool is likely to be formed, and conversely, at a position of 30 mm or more from the side edge of the absorber, the urine absorption area becomes narrower, and conversely, it tends to leak. The mounting method includes a method using a hot melt adhesive, a heat seal welding method, an ultrasonic welding method, etc., alone or in combination. The folded length of both side edges of the topsheet is
The length should be longer than the length that wraps the stretchable elastic body to be installed inside, but for leakage, the length in which the second flap is doubled is more preferable, and the length covering the side edge of the absorber is more preferable. More preferred.

Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 shows a partial cross-sectional view of the disposable diaper of the present invention in the lateral direction, wherein reference numeral 1 denotes a top sheet, 2 denotes an absorber, 3 denotes a back sheet, 4, 4 ′ denotes a stretchable elastic body, 5,
5 'is a hot melt adhesive, 6 is a second flap, 7 is a side flap, and 8 is a film or sheet material separate from the topsheet. After applying the hot melt adhesive 5 to the back side of both side edges of the topsheet 1, the elastic elastic body is adhered in a stretched state, and then the inner side is wrapped around the elastic elastic body 4 outside the adhesive 5 applied portion. The second flap portion 6 is configured to be folded to the (back side). And the second
At the base of the flap portion, the edge of the film or sheet material 8 separate from the top sheet is adhered to the edge of the film or sheet material 8 by a hot melt adhesive 5 ', and the film or sheet material separate from the top sheet is used. The outside flap 8 and the back sheet 3 are bonded together to form a side flap 7. Further, an elastic elastic body 4 ′ may be provided on the side flap along the crotch of the absorber 2.

Next, a method for manufacturing a disposable diaper according to the present invention will be described with reference to FIG. 2, the same reference numerals as those in FIG. 1 have the same meanings as those in FIG. 1, reference numeral 9 denotes a center drum, reference numeral 9 'denotes a pressing drum, and reference numeral 10 denotes a bending section. The topsheet 1 sent from the topsheet roll is sent in the direction of the arrow while applying the hot melt adhesive to both side edges thereof, and the stretchable elastic body 4 is stretched to the hot melt adhesive application section. And then, in the bending step section 10, bending outside the portion where the adhesive is applied so as to wrap the elastic elastic body inside,
By bonding the ends, a bag-shaped second flap is formed, and then the edges of the sheet material 8 are bonded at the bases of the second flaps formed on both sides of the topsheet. Next, elastic elastic members 4 'are adhered to both side edges of the back sheet 3 sent from the back sheet roll, and the absorber is sent on the back sheet at a predetermined interval to the center thereof. After the back sheet and the top sheet bonded to the sheet material are bonded and laminated between a center drum and a press drum, the present invention is realized by cutting between absorbers and cutting into a predetermined shape. You can get a disposable diaper.

[Brief description of the drawings]

FIG. 1 is a diagram showing a partial cross-sectional view in the lateral direction of the disposable diaper of the present invention, and FIG. 2 is a process diagram for explaining a manufacturing process of the disposable diaper of the present invention.

[Explanation of symbols]

1 top sheet, 2 absorber, 3 back sheet, 4,
4 ': elastic elastic body, 5, 5': hot melt adhesive,
Reference numeral 6: second flap, 7: side flap, 8: film or sheet material separate from the top sheet, 9: center drum, 9 ': pressing drum, 10: bending section

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-105102 (JP, A) JP-A-3-188885 (JP, A) UK patent 2161059 (GB, B) (58) Fields investigated (Int) .Cl. ⁷ , DB name) A61F 13/15-13/84

Claims (1)

(57) [Claims] 1. Before bonding a top sheet having both side edges bent so as to wrap a stretchable elastic body 4 inside thereof with a back sheet 3 and an absorber 2, the both side edges are stretched with a stretchable elastic body 4. And a sheet-like material 8 separate from the surface sheet forming the side flaps 7 along the base of the second flap, by folding the sheet so as to wrap it inside. A liquid-permeable top sheet 1 and a liquid-impermeable back sheet 3 and an absorber 2 therebetween, and extending outward from both lateral edges of the absorber. It has a protruding side flap 7 and has a second flap 6 installed along both side edges of the absorber, and the side flap is a film or sheet separate from the back sheet and the top sheet. Is made by bonding the shape material The method for manufacturing a disposable diaper, wherein the second flap has a base end located on a topsheet 1 to 30 mm inside from both side edge positions on the absorber, and stands up.