JPH07255778A - Disposable brief type underpants - Google Patents

Abstract

PURPOSE:To provide disposable brief type underpants to which elastic members are fitted without being unnaturally twisted or mutually crossed although the elastic members of leg holes are bent almost in the shape of comparatively sharply curved U. CONSTITUTION:Elastic members 5 of leg holes are bent unward in almost the shape of U from first and second elastic members 5A and 5B while composing those elastic members of plural elastic threads, a central part 5a of those respective elastic members is made cross the crotch area of the underpants, and both side parts 5b of those elastic members are respectively arranged along almost the front half and almost the back half of both the leg holes.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to disposable brief pants, and more particularly to such pants diapers and infant training pants.

[0002]

2. Description of the Related Art Conventionally, brief type pants of this type have been disclosed in JP-A-57-77304 and JP-A-5-35304.
7-117602 is known. These disclose a technique for attaching elastic members to a waist hole and leg holes of pants.

As in the above-mentioned known technique, in order to continuously displace and bend an elastic member on a web in one direction, the elastic member is controlled by a traverse means, and the elastic member coated with the adhesive is traversed. If you want to go through the means,
A certain amount of adhesive adheres to the traverse means and is peeled off to reduce the adhesive effect, and there is a complication that the passage portion of the traverse means must be constantly cleaned.

In the above-mentioned prior art, since one elastic cord is used as the elastic member, it is recognized that the cross-sectional diameter is relatively large in order to obtain the required elongation stress. If a tape-shaped tape with a large dimensional difference between the thickness and the width is used, when the elastic member is displaced in a certain direction by the traverse means, the elastic member is strongly twisted and adheres to the web, which causes the peeling from the web. However, the twisted portion is often raised, but this causes a problem that the wearer feels uncomfortable.
This is a particular problem when using multiple elastic members.

An object of the present invention is to use a plurality of elastic yarns as elastic members of a leg hole and to bend these into a curve having a relatively small radius of curvature, but the elastic yarns are unnaturally twisted or cross each other. (EN) Disposable brief-type pants in which elastic yarns are mounted in orderly spaced apart side by side.

[0006]

According to the present invention, an absorbent core is interposed between a top sheet and a back sheet, and an elastic member is attached in a stretched state around a waist hole and a pair of leg holes. We assume that you have disposable brief pants.

The present invention is characterized by the following points on the above premise.

A) The elastic member of the leg hole is composed of a first elastic member and a second elastic member, and the first elastic member and the second elastic member are respectively composed of a plurality of elastic yarns, and the central portion and both side portions are formed. An upwardly curved, generally U-shaped point having and.

B) In each row of the first and second elastic members, the elastic threads are arranged in parallel without crossing each other,
Also, the elastic threads on at least the both side portions of the first and second elastic members are separated from each other.

C) The central portions of the first and second elastic members are lined up on the lower surface of the core and cross the crotch region of the pants, and the both side portions of the first elastic member are substantially the first half of both leg holes. A point that is located along the minute, and the both side portions of the second elastic member are located along substantially the rear halves of the both leg holes.

E) Apart from the stretchability of the portions of the top sheet and the back sheet provided by the elastic members, at least the portion of the portion covering the waistline of the wearer between the waist hole and the leg holes. The point that the back sheet is stretched in the lateral direction.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a perspective view of a disposable brief type pants according to the present invention. Pants 1 are waist holes 2
, And a pair of leg holes 3, and elastic members 4 and 5 for forming stretchable gathers are attached along the circumference of these leg holes.

FIG. 2 shows an exploded perspective view of the brief 1. The pants 1 includes a top sheet 6 and a back sheet 7, each of which is formed of a fibrous nonwoven fabric that can be stretched in the vertical and horizontal directions.
It is composed of a mat-shaped absorbent core 8 interposed between these and the elastic members 4 and 5. Top sheet 6
And the back sheet 7 has recessed portions 13a 1 and 13 2 on both sides.
b is formed. The core 8 also has recessed portions 10 formed on both sides. The core 8 is formed mainly of fluff pulp. The elastic member 4 is attached between the waist portions 11 and 12 of the top sheet 6 and the back sheet 7 via a later-described adhesive so as to be stretchable in the lateral direction thereof.

The elastic member 5 includes the first and second elastic members 5.
It is composed of A and 5B. Each of the first and second elastic members 5A and 5B is composed of a plurality of elastic threads,
It has a central portion 5a and both side portions 5b, and is curved upward, that is, in a substantially U-shape facing the waist hole 3. In the first and second elastic members 5A and 5B, the elastic yarns in each row are spaced in parallel without intersecting each other. In the first and second elastic members 5A and 5B, the central portions 5a cross the crotch region of the pants 1 in parallel to each other, and
Both side portions 5b of the elastic member 5A are located along substantially the front halves of both leg holes 3, and both side portions 5b of the second elastic member 5B are located along the substantially rear half of the leg holes 3.
Only b is fixed between the topsheet 6 and the backsheet 7.

FIG. 3 shows a schematic view of an apparatus for manufacturing the pants 1. The continuous web 27, which is the material of the back sheet 7, has rollers 102a, 102a,
It is guided to the adhesive application section 102 composed of 102b and 102c. In the coating section 102, as shown in FIG. 4 (A), a hot-melt adhesive is applied to the central region of the web 27 at predetermined intervals in the lengthwise direction of the web 27 to form an elliptical shape slightly longer in the widthwise direction of the web 27. Adhesive area 30a is provided. Further, the web 27 has a width direction tension roller 1 for them.
03 and the pressure roller 104, it is guided to the rotary drum 106 in the assembly station 105. On the other hand, the material of the elastic members 5A and 5B is 3
The continuous elastic members 25A and 25B made of a single elastic yarn are guided to the traverse means 108 and 109 while being stretched by the pulling roller 107 to a required magnification.

6 and 7, the traverse means 10 is shown.
The schematic perspective view and sectional drawing of the mechanism of 8 and 109 are shown. The traverse means 108 and 109 respectively include support cylinders 110 and 111 facing the pressure roller 104 in parallel therewith, sliding rods 112 and 113 inserted into the support cylinders, and the sliding rods. Support piece 11 fixed to the tip of
It includes guide rods 116 and 117 which are vertically installed at 4,115. The sliding rods 112 and 113 are controlled by a cam mechanism (not shown) linked to their base ends.
The guide rods 116 and 117 have bent portions 118 and 119 at their lower ends.
Has thread guide holding portions 118a, 119a each consisting of three short tubes arranged in parallel in the lateral direction and intersecting the longitudinal axis of the web 27 at a right angle. The separation / parallel direction (angle) of the yarn guide holding portions 118a, 119a with respect to the longitudinal axis of the web 27 is important for maintaining the separation / parallel of the elastic yarns of the elastic members 25A, 25B bonded to the web 27, The one shown in the figure is a preferred example, and the separation and parallel state of the elastic yarns with respect to the web 27 can be changed by the angle thereof. Thread guide holder 118a, 119a
Each of the elastic threads of the elastic members 25A and 25B is inserted into each of the above. The lower ends of the yarn guide holding portions 118a and 119a face the surface of the pressure roller 104 in close proximity. The sliding rods 112, 113 are guide rods 116, shown in FIG.
The cam mechanism is controlled to move by a distance between the solid line position and the chain line position of 117. By the movement of the sliding rods 112, 113 under this control, that is, the movement of the guide rods 116, 117, the yarn guide holding portions 118a, 118a,
Elastic members 25A and 25B that are inserted into the adhesive region 119a and have elastic threads arranged narrower than the application width of the adhesive forming the adhesive region 30a are formed on the adhesive region 30a as shown in FIG. 4B. A sine curve-shaped curve, that is, a mountain portion and a mountain, which are provided along the substantially half circumference of the bonding area of the web 27 which is provided and moves, and which are opposed to each other in the width direction of the web 27 while intersecting between the adjacent bonding areas. Portions or troughs and the troughs are drawn so as to face each other, and the elastic yarns of the elastic members 25A and 25B are arranged so that they do not overlap and do not intersect each other.

FIG. 8 shows the sliding rod 112 and the guide rod 116.
Sectional view of a mechanism for controlling the movement of the elastic member 25A to deform a part of a sine curve-shaped curve drawn by the elastic member 25A,
FIG. 9 shows a plan view of the deformed state. In the vicinity of the front end of the support cylinder 110 shown in FIG. 6, the regulating rods 120 and 121 are inserted and fixed at a distance in the lengthwise direction of the sliding rod 112. Sliding rail 12 installed between pieces 120 and 121
A support piece 114 for supporting the guide rod 116 is slidably inserted into and supported by the guide rod 116, and a coil spring 123 is interposed between the support piece 114 and the restriction piece 120. A stopper 125 is provided which abuts the side surface of the support piece 114 from the immovable portion 124 at a predetermined position. If such a mechanism is not attached to the sliding rod 112, the sliding rod 112
And the movement of the guide rod 116 causes the elastic member 25A to be arranged so as to draw a sine curve-shaped curve having an arcuate portion 25A '. In the case where such a mechanism is attached to the sliding rod 112 as shown in FIG. When the support piece 114 supporting the guide rod 116 abuts against the stopper 125, the sine curve-shaped curve of the elastic member 25A is deformed by the straight line portion 25A ″.
The guide rod 11 is pressed by the contact of the stopper 14 with the stopper 125.
6 shows the position where 6 is temporarily stopped from moving.
As described above, the sine curve-shaped curve of the elastic member 25A is deformed to improve the wearability in accordance with the shapes of the leg hole 3 of the brief 1 and the front crotch of the wearer shown in FIG.

The web 27, on which the elastic members 25A and 25B are arranged as described above, is pressed by the pressing roller 104, and the elastic members are bonded to the web. At this time, as shown in FIG. 4C, the portions 25a of the elastic members 25A and 25B that are not located in the bonding area 30a contract and take a substantially linear shape. Therefore, the extension stress of the portion 25a (the central portion 5a in FIG. 2) becomes weaker than the extension stress of the other portions (the central portion 5b in FIG. 2) of the elastic members 25A and 25B.

Referring again to FIG. 3, the top sheet 6
The continuous web 26, which is the material of
And the width direction tension roller 127 for the web, and is guided to the adhesive application portion 128 including the rollers 128a, 128b, 128c and 128d. In the coating part 128, as shown in FIG. 4 (D), a hot melt adhesive is applied to the central region of the web 26 at predetermined intervals in the length direction of the web 26 to form an elliptical adhesive which is slightly longer in the width direction. Area 30
b is provided. The shape, size, and spacing of the adhesive zone 30b are substantially the same as those of the adhesive zone 30a. at the same time,
The web 26 has a straight bonding area 31 extending from both sides of the bonding area 30b to both side edges of the web 26, and a straight bonding area 32 continuous along both side edges of the web 26 in its length direction. It is provided by applying a hot-melt type adhesive in the applying section 128. Further, the web 26 is guided through the widthwise tensioning roller 129 between the rotary drum 106 and the sandwiching roller 130 that is in contact with the rotary drum 106.

On the other hand, the continuous elastic member 24, which is the material of the elastic member 4, is stretched by the pulling roller 131 to a required ratio and, as shown in FIG. Guided to be placed along.

Referring again to FIG. 3, the individual cores 8 preformed by the porous belt conveyor 133 moving on the upper surface of the device 132 having a weak suction action and kept at predetermined intervals are guided to the assembly station 105. . The core 8 is formed in an hourglass shape as shown by a chain line in FIG. 2 and FIG.
It is arranged on the web 27 between a, that is, between the two adjacent loop portions formed by the elastic members 25A and 25B. In addition, the web 27 on which the core 8 is arranged has the adhesive area 3
The webs 26 are superposed so that 0a and 30b match. As a result, the loop portions of the elastic members 25A and 25B are sandwiched between the adhesive areas 30a and 30b, and the elastic member 24 is sandwiched between both side edges of the webs 26 and 27. Thus, the core 8 is placed between the webs 26 and 27.
The elastic member 24, 25A, 25B is sandwiched between the rotary drum 106 and the pinching roller 130 to form a continuous composite web 28 while being sandwiched between the rotary drum 106 and the pinching roller 130.
The core 8 and the elastic members 24, 25A, 25B are fixed in the inside 8.

The core 8 in the composite web 28 has a pedestal 13
The pressure is applied by the embossing section 137 composed of the belt conveyor 135 moving on the upper surface of 4 and the pressing roller 136, and is guided to the heat (or sonic) sealing roller 138. The composite web 28 includes the elliptical area 21 between the adjacent cores 8 shown in FIG. 5A and the straight portions 22 extending from both sides thereof to the respective side edges of the composite web 28.
It is heat-sealed to the extent that it does not harden. However, this step is not always necessary.

The composite web 28 treated in this way is guided to the roller cutter 140 via the guide roller 139 and the central portion 21 'of the elliptical region 21 shown by the oblique lines is cut off, so that the leg hole notch 23 is formed. It is formed. The central portion 21 'is a part of the webs 26, 27 located inside the annular area formed by the adhesive areas 30a, 30b and the elastic members 25A, 25B adhered thereto.

The composite web 28 having the notch 23 formed therein is guided to the folding means 142 via the guide roller 141. Although the structure of the folding means 142 is not shown, it may be a known structure in a manufacturing apparatus such as disposable diapers and sanitary napkins. The composite web 28 is folded in two by the folding means 142 as shown in FIG. 5 (B) along the longitudinal centerline 34 shown in FIG. 5 (A).

The composite web 28 folded in two is guided to the heat (or sonic) sealing roller 143,
As shown in FIG. 5 (C), by providing the two strip-shaped heat-sealing regions 36 that are spaced apart and opposed to each other along the vicinity of the virtual cutting lines 35 on both sides of the adjacent briefs 1 by the heat-sealing roller 143, The individual briefs 1 are formed in a continuous brief 29 which is oriented in the transverse direction orthogonal to the lengthwise direction of the composite web 28 and juxtaposed in the lengthwise direction.

The continuous brief 29 is guided to the roller cutter 144 via the guide roller 145, and as shown in FIG. 5 (C), a cutting virtual position located substantially in the middle between the two strip-shaped heat seal areas 36 facing each other. Individual pants 1 are obtained by dividing the pants 1 along the line 35. The strip-shaped heat seals 36 on both sides of each of the pants 1 are harder than the portions which are not heat-sealed, but since they are positioned with both outer edges of the pants 1 left, the outside of the hard strip-shaped heat seal 36. There is no risk of the edges rubbing on the wearer's skin and damaging it. The individual pants 1 are transferred to the packaging process (not shown) on the belt conveyor 146.

A liquid permeable web is used for the continuous web 27, which is the material of the back sheet 7, and at least the core 8 is provided to prevent leakage of body fluid from the center surface area occupied by the back sheet. If it is desired to make the area liquid impermeable, a liquid impermeable web such as a plastic film, preferably a stretchable web, is bonded to the central surface area of the web 27 before the elastic members 25A and 25B are arranged. do it. In this case, in FIG. 3, the coating roller 14 that is in contact with the pressure roller 147 is in contact with the central surface area of the web 27.
At 8, the hot melt adhesive is applied in a scattered manner, and the liquid impermeable continuous web 40 is bonded to the central surface area. Therefore, in this case, the application of the adhesive by the application unit 102 and the arrangement of the elastic members 25A and 25B are performed by the web 40.
And a part of the web 27. The webs 26, 27 are preferably stretchable non-woven fabrics in the longitudinal and transverse directions, at least in the transverse direction, and the core 8 is formed by mixing fluff pulp with superabsorbent polymer powder. For 25A and 25B, a natural or synthetic rubber or a plastic exhibiting elasticity by heat treatment is preferably used.

The step of cutting the portion 21 'of the composite web 28 to form the leg hole notch 23 is the step of FIG. 5B instead of the step of FIG. 5A. Good.

[0030]

According to the disposable brief type pants according to the present invention, the following effects can be obtained.

Since elastic yarn is used for the elastic member of the leg hole, even if the elastic member has a plurality of elastic members and is curved in a substantially U-shape which can be said to be a curve having a relatively small radius of curvature, the elastic member is elastic. The elastic yarns of the member are strongly twisted so that the elastic yarns are not overlapped with each other, or the elastic yarns are not crossed with each other and are attached in an orderly manner. Therefore, the adhesion of the elastic member to the sheet is reduced,
The adhesive state is not deformed, and the elastic member is not partially raised to give the wearer a feeling of discomfort (claim 1).

In the pants, since not only the parts by the elastic members of the waist and the leg holes but also the part other than the waist hole that covers at least the waistline of the wearer has the elasticity in the lateral direction, the pants located on the outer surface are located. Since the seat acts to press the inner part of the pants toward the body side, it fits relatively well to the body and slips down even if the wearer exercises relatively hard, so excrement leaks delusionally. There is nothing to do (Claim 1).

Further, although the stretching stresses of the central portions of both elastic members are weaker than the stretching stresses of both side portions thereof, the central portions are on the lower surface of the absorbent core in the crotch region of the pants and support the same. Therefore, even if the core absorbs excrement and becomes heavy, the pants do not slip down, and since the contraction stress is so weak, a strong contraction differential action of the elastic member causes delusionally wrinkles in the crotch region. Never (Claim 1,
2).

[Brief description of drawings]

FIG. 1 is a perspective view of disposable brief type pants according to the present invention.

FIG. 2 is an exploded perspective view of the pants.

FIG. 3 is a schematic view of an apparatus for manufacturing the pants.

FIG. 4 is a partial plan view showing an assembling process of the pants by (A) to (E).

FIG. 5 is a partial plan view showing an assembling process of the underpants according to FIGS.

FIG. 6 is a partially enlarged perspective view of traverse means in the apparatus.

FIG. 7 is a partial sectional view of the traverse means.

FIG. 8 is a cross-sectional view showing a traverse deformation mechanism in the traverse means.

FIG. 9 is a layout plan view of an elastic member that is deformed by the traverse deformation mechanism.

[Explanation of symbols]

 1 Pants 2 Waist Hole 3 Leg Holes 4,5 Elastic Member 5A First Elastic Member 5B Second Elastic Member 5a Central Part 5b Both Sides

Claims (2)

[Claims] 1. Disposable brief-type pants in which an absorbent core is interposed between a top sheet and a back sheet, and elastic members are attached in a stretched state around a waist hole and a pair of leg holes. The elastic member of the leg hole is composed of a first elastic member and a second elastic member, and the first elastic member and the second elastic member are composed of a plurality of elastic threads, respectively, and has a central portion and both side portions. It is curved in a U-shape, and in each row of the first and second elastic members, the elastic yarns are arranged in parallel without intersecting each other, and each of the first and second elastic members has at least the both side portions. Elastic yarns are spaced apart from each other, the central portions of the first and second elastic members are arranged side by side on the lower surface of the core and cross the crotch region of the pants, and the both side portions of the first elastic member are formed. The top sheet provided by the elastic members, the front seat being provided along substantially the front halves of the both leg holes and the both side portions of the second elastic member being located along the rear halves of the both leg holes; Apart from the elasticity of the part of the back sheet, at least the part of the back sheet that covers the waistline of the wearer between the waist hole and the leg hole is stretched in the lateral direction. The above-mentioned pants characterized. 2. The underpants according to claim 1, wherein the extension stresses of the central portions of the first and second elastic members are made weaker than the extension stresses of the both side portions of the both elastic members.