UNDERPANTS TYPE DISPOSABLE DIAPER AND METHOD FOR MANUFACTURING THE SAME

• US 20110288517A1
• Filed: 01/18/2010
• Published: 11/24/2011
• Est. Priority Date: 01/19/2009
• Status: Active Grant

• Current Assignee: DAIO Paper Corporation
• Original Assignee: DAIO Paper Corporation
• Inventors: Mori, Yosuke
• Granted Patent: US 9,060,899 B2
• Time in Patent Office: Days
• US Class Current: 604/385.3
• CPC Class Codes: A61F 13/15756 Applying tabs, strips, tapes, loops; Knotting the ends of pads
• CPC Class Codes: A61F 13/15804 Plant, e.g. involving several steps
• CPC Class Codes: A61F 13/49011 the elastic means is located at the waist region
• CPC Class Codes: A61F 13/496 in the form of pants or briefs

Abstract

[Problem] To provide an underpants type disposable diaper that can be formed such that the edges of the leg openings fit the groin and gluteal portions of a wearer with no or less trim loss than conventional diapers

[Means for Solving Problem] The above problem is solved by that the ventral side outer sheet 12F and the back side outer sheet 12B each have a separated portion 12S formed by a slit or an elongated opening so as to extend in a width direction at a lengthwise middle section in a widthwise central region, a connecting member 12M connects the both outer sheets 12F, 12B at widthwise middle portions on the crotch side with respect to the separated portions, and the both outer sheets 12F, 12B are pulled up toward the waist side at entire widthwise sections on the waist side with respect to the separated portions 12S while being deformed with increased longitudinal separation distances of the separated portions 12S, and are diagonally pulled up toward the waist side at sections on the crotch side with respect to the separated portions 12S and at the same time, on both widthwise sides of connecting portions 12x connected to the connecting member, with increasing proximity to the both widthwise sides.

[Selected Drawing] FIG. 2

Claims

1. An underpants type disposable diaper, comprising:

a barrel shaped abdomen portion that is formed by joining together a ventral side outer sheet and a back side outer sheet at both sides; and

an inner body for absorbing excrement that is provided ranging from a widthwise middle portion in an inner surface of the ventral side outer sheet to a widthwise middle portion in an inner surface of the back side outer sheet,

the ventral side outer sheet and the back side outer sheet being not connected but separated at a crotch side, wherein

the ventral side outer sheet and the back side outer sheet each have a separated portion formed by a slit or an elongated opening so as to extend in a width direction at a lengthwise middle section in a widthwise central region,

a connecting member connects the ventral side outer sheet at a widthwise middle portion on the crotch side with respect to the separated portion, to the back side outer sheet at a widthwise middle portion on the crotch side with respect to the separated portion,

front and back end portions of the inner body are fixed to the ventral side outer sheet at a section on the waist side with respect to the separated portion, and to the back side outer sheet at a section on the waist side with respect to the separated portion, respectively and

the ventral side outer sheet and the back side outer sheet are pulled up toward the waist side at entire widthwise sections on the waist side with respect to the separated portions while being deformed with increased longitudinal separation distances of the separated portions, and are diagonally pulled up toward the waist side at sections on the crotch side with respect to the separated portions and at the same time, on both widthwise sides of connecting portions connected to the connecting member, with increasing proximity to the both widthwise sides.

2. The underpants type disposable diaper according to claim 1, wherein

a first elongated elastic member is fixed in the width direction in a longitudinally stretched state to the ventral side outer sheet and the back side outer sheet on the waist side with respect to the separated portions, and a second elongated elastic member is fixed in a longitudinally stretched state to the ventral side outer sheet and the back side outer sheet in the width direction at positions overlapping the connecting portions and in the diagonal direction on the both sides of the connecting portions, on the crotch side with respect to the separated portions.

3. The underpants type disposable diaper according to claim 2, wherein

the second elongated elastic member is thicker than the first elongated elastic member, and is fixed at a lower extension ratio than that of the first elongated elastic member.

4. A method for manufacturing an underpants type disposable diaper having:

a barrel shaped abdomen portion that is formed by joining together a ventral side outer sheet and a back side outer sheet at both sides; and

an inner body for absorbing excrement that is provided ranging from a widthwise middle portion in an inner surface of the ventral side outer sheet to a widthwise middle portion in an inner surface of the back side outer sheet,

the ventral side outer sheet and the back side outer sheet being not connected but separated at a crotch side,

the method comprising;

a separated portion forming step of feeding a band-like portion to be the ventral side outer sheet and a band-like portion to be the back side outer sheet in a direction of continuation thereof; and

forming a separated portion as a slit or an elongated opening in the portion to be the ventral side outer sheet and in the portion to be the back side outer sheet so as to extend in an MD direction at a middle section in a CD direction of a central region in the MD direction;

a connecting step of, after the separated portion forming step, connecting, with a connecting member, the portion to be the ventral side outer sheet at a middle section in the MD direction on the center side in the CD direction with respect to the separated portion, to the portion to be the back side outer sheet at a middle section in the MD direction on a center side in the CD direction with respect to the separated portion;

a widening step of, after the connecting step, pulling up the portion to be the ventral side outer sheet and the portion to be the back side outer sheet, at entire sections in the MD direction on the outside in the CD direction with respect to the separated portions, and at sections on the center side in the CD direction with respect to the separated portions and at the same time on the both sides of connecting portions connected to the connecting member in the MD direction, toward the outside in the CD direction of the connecting portions connected to the connecting member;

while the separated portions are deformed with increasing separation distances in the CD direction thereof, extending the portion to be the ventral side outer sheet and the portion to be the back side outer sheet, at the entire sections in the MD direction on the outside in the CD direction with respect to the separated portions, toward the outside in the CD direction, and extending diagonally the portion to be the ventral side outer sheet and the portion to be the back side outer sheet, at sections on the center side in the CD direction with respect to the separated portions and at the same time, on the both sides in the MD direction of the connecting portions connected to the connecting member, so as to come closer to the outside in the CD direction with increasing proximity to the both sides in the MD direction;

an inner body fabricating step of fabricating the inner body;

an inner body attaching step of, after the widening step, fixing front and back end portions of the inner body fabricated in the inner body fabricating step, to the portion to be the ventral side outer sheet at a section on the outside in the CD direction with respect to the separated portion and to the portion to be the back side outer sheet at a section on the outside in the CD direction with respect to the separated portion, respectively;

a folding step of, after the inner body attaching step, folding the portion to be the ventral side outer sheet and the portion to be the back side outer sheet in the CD direction, such that surfaces thereof for attachment to the inner body overlap; and

a side portion joining/separating step of, after the folding step, joining together the portion to be the ventral side outer sheet and the portion to be the back side outer sheet, at both sides of individual diapers, and cutting the portion to be the ventral side outer sheet and the portion to be the back side outer sheet at boundaries of individual diapers, thereby to obtain individual diapers.

5. The method for manufacturing an underpants type disposable diaper according to claim 4, wherein

a first elongated elastic member is fixed in the MD direction in a longitudinally stretched state to the portion to be the ventral side outer sheet and the portion to be the back side outer sheet on the outside in the CD direction with respect to the separated portions, and a second elongated elastic member is fixed in the MD direction in a longitudinally stretched state to the portion to be the ventral side outer sheet and the portion to be the back side outer sheet on the center side in the CD direction with respect to the separated portions.