Disposable diaper

A disposable diaper has front and rear waist regions adapted to be separably connected to each other by surface fasteners. Each surface fastener has a hooked fastener component and a looped fastener component operatively associated with the hooked fastener component. At least a pair of wings extending outward from transversely opposite sides of the rear waist region have their outer surfaces made of nonwoven fabric with which the component can be interlocked, enabling the used disposable diaper to be reliably rolled-up for disposal.

BACKGROUND OF THE INVENTION 
The present invention relates to a disposable diaper having front waist and 
rear waist regions adapted to be separably connected to each other in its 
actual use. 
There is disclosed in Japanese Laid-Open Utility Model Application No. 
Hei6-61227 a disposable diaper having front and rear waist regions 
separably connected to each other by a pair of surface fasteners each 
comprising a hooked fastener component and a looped fastener component. In 
this diaper, a pair of tape strips extend outward from transversely 
opposite side edges of the rear waist region, respectively. Each of the 
tape strips carries on its inner surface the hooked fastener component, an 
adhesive zone and a cover zone to protect the adhesive zone arranged in 
this order starting from the longitudinally inner end of the tape strip. 
For disposal, the used diaper is rolled up and the adhesive zones on the 
respective tape strips get interlocked with the diaper at appropriate 
locations thereof to keep it in a rolled-up state. 
With the diaper being worn on the baby's body, the hooked fastener 
components on the respective tape strips are interlocked with the 
associated looped fastener components, and the adhesive zones on the 
respective tape strips are covered with the folded cover zones on the same 
tape strips so as to form tabs. The adhesive zones must have sufficient 
lengths to assure that the used diaper is reliably kept in its rolled-up 
state and the tabs inevitably have correspondingly long dimensions. 
Consequently, there is an apprehension that the baby wearing such a diaper 
may easily hold these long tabs and take of f the diaper by him- or 
herself. 
SUMMARY OF THE INVENTION 
Accordingly, it is a principal object of the invention to provide a 
disposable diaper adapted to be reliably kept in its rolled-up state for 
disposal after its use and being free from the above-mentioned 
apprehension. 
The object set forth above is achieved, according to the invention, by a 
disposable diaper comprising a liquid-permeable topsheet, a 
liquid-impermeable backsheet and a liquid-absorbent core disposed between 
these two sheets, respective pairs of front and rear wings extending 
outward from transversely opposite sides of front and rear waist regions 
of the diaper, one of the pairs carrying a pair of hooked fastener 
components and the other pair carrying a pair of looped fastener 
components adapted to be separably interlocked with the hooked fastener 
components, the diaper being characterized by that the hooked fastener 
components are bonded to inner surfaces of the front or rear wings and 
outer surfaces of the wings are made of nonwoven fabric with which the 
hooked fastener components are peelably interlocked.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
A diaper 1 shown by FIG. 1 in a plan view as partially broken away 
comprises a liquid-permeable topsheet 2, a liquid-impermeable backsheet 3 
and a liquid-absorbent core 4 disposed between these two sheets 2, 3. The 
diaper has a front waist region 6, a rear waist region 7 and a crotch 
region 8 extending between these two regions 6, 7. The front and rear 
waist regions 6, 7 are provided along their transversely opposite sides 
with front wings 11 and rear wings 12, respectively. The topsheet 2 and 
backsheet 3 are put one upon another over their portions extending outward 
beyond a peripheral edge of the core 4 and inner surfaces of these 
portions are water-tightly bonded together. The crotch region 8 is 
provided adjacent its transversely opposite side edges with elastic 
members 13 adapted to surround the wearer's legs and the rear waist region 
7 is provided adjacent its longitudinal end with an elastic member 14 
extending along the waist line. These members 13, 14 are disposed between 
the topsheet 2 and backsheet 3 and secured in an elastically contractible 
condition to the inner surface of at least one of these two sheets 2, 3. 
A hooked fastener component 15 having a plurality of hook elements, one 
component of a surface/mechanical fastener known under the trademark of 
Velcro, is anchored to the inner surface of each rear wing 12 and a part 
of this hooked fastener component 15 extending aside to an outer side edge 
12A of the wing 12 has its inner surface covered with a protective sheet 
18. A looped fastener component 16 having a plurality of loop elements, 
the other component of the surface/mechanical fastener, is anchored to the 
outer surface of each front wing 11 so as to extend transversely thereof. 
FIG. 2 is a sectional view taken along a line II--II in FIG. 1. As shown, 
an inner side edge 12B of each rear wing 12 is joined to a side edge of 
the outer surface of the backsheet 3. An exposed portion of the hooked 
fastener component 15 defined by a width A is peelably interlocked with 
the associated looped fastener component 16 while the portion defined by a 
width B covered with the protective sheet 18 does not participate in 
fastening. The hooked fastener component 15 once interlocked with the 
associated looped fastener component 16 is pulled in the direction as 
indicated by an arrow P with the outer side edge 12A of the rear wing 12 
being held by the user's fingers so that the portion defined by the width 
A may be peeled off from the rear wing 12 starting from its right side, as 
indicated by the imaginary lines. In this state, so-called peeling force 
is practically ineffective between the rear wing 12 and an outer side edge 
20 of the hooked fastener component 15, so the outer side edge 20 is not 
peeled off from the rear wing 12. 
FIG. 3 is a perspective view showing the used diaper 1 as rolled up for 
disposal. The diaper 1 is rolled-up starting from the front waist region 6 
toward the rear waist region 7 with the topsheet 2 inside, and then the 
rear wings 12 are folded inward so that the hooked fastener component 15 
associated with one of the rear wings 12 may be interlocked with the outer 
surface of the other rear wing 12. With the diaper 1 according to the 
illustrated embodiment, such fastening of the member 15 is facilitated by 
using nonwoven fabric such as spun lace nonwoven fabric or spun bond 
nonwoven fabric which is bulky and relatively fluffy, or composite fiber 
nonwoven fabric comprising crimped fibers entangled together and thereby 
forming a plurality of fine loops, to make at least the rear wings 12 or 
their outer surfaces. If the topsheet 2 and/or the backsheet 3 are made of 
such nonwoven fabric, the rear waist region 7 of these sheet 2 and/or 
sheet 3 may be transversely extended so as to form the respective rear 
wings 12. If the rear wings 12 are provided with, instead of the hocked 
fastener components 15 as illustrated, so-called tape fasteners comprising 
tape strips laterally extending from outer ends of the respective rear 
wings 12 and the hooked fastener components 15 are respectively bonded to 
inner surfaces of the tape strips, the tape strips or outer surfaces 
thereof may be also made of the nonwoven fabric so that the hooked 
fastener components 15 can be interlocked with such nonwoven fabric. 
To implement the invention, the appropriate materials commonly used in the 
concerned field of technique may be used for the topsheet 2 and the 
backsheet 3. In the illustrated embodiment, nonwoven fabric or plastic 
film which is less rigid than the hooked fastener component 15 and 
agreeable to the touch is used as material for the protective sheet 18. 
Bonding of the respective components or members may be achieved by use of 
adhesive, e.g., of hot melt type or by utilizing a heat-seal technique so 
far as the components or members to be bonded are of heat-sealable nature. 
It should be noted that no specific manner of bonding is illustrated. 
With the inventive diaper, the front and rear waist regions are separably 
connected to each other by the surface fastener comprising the hooked 
fastener component and the looped fastener component wherein the diaper 
wings are made of nonwoven fabric with which the hooked fastener component 
can be interlocked so that, after the used diaper has been rolled-up for 
disposal, the hooked fastener component can be reliably interlocked with 
the nonwoven fabric to keep the used diaper in the rolled-up state. The 
diaper of such arrangement requires no adhesive fastening means to retain 
the diaper in the rolled-up state and allows a tab used to peel off the 
hooked fastener component from the rear wing to be formed in a small size, 
so that as it will be difficult for the baby to hold the tab.