Note: Descriptions are shown in the official language in which they were submitted.
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This invention is directed to an economical but
efficiant syste~ Eor releasably fastening artiales of apparel.
Since it is particularly concerned with those articles generally
known as disposable diapers, reference will be mada ~hereto for
purposes o~ i.llustration in the following description.
Typically, disposable diapers comprise a porous
absorbent material for placement against the body and an outer
liquid-impermeable liner. Obviously, means must be provided for
releasably securing the diaper on the body.
The evolution of diaper closure systems has progressed
through several stages from pins through pexmanently positioned
tapes; movable tapes with the attachment area on the diaper
specially reinforced to prevent tearing; then to movable tapes
having a thicker attachment area with a roughened surface intended
to decrease adhesion and, in turn, to prevent tearing; and finally
~o the so-called "repositionable tapes" currently employed on
virtually all of the disposable diapers now on the market. These
xepositionable tapes generally are in the ~orm of a tab engaging
opposed edges adjacent one end of the diaper and adapted for
releasably securing the plastic liner on the opposeq end when the
two ends are brou~ht in superposition ~o cover the front and back
lower region of the corpus.
As will be described in more detail hereinafter, these
adhesive tabs are usually composed of two sheet materials, each
carrying an adhesive surface. The adhesive layer on the first of
these sheet materiais is adapted for permanently securing this
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sheet material and an underlying portion of the second sheet
material to the inner surface of the diaper. The second of these
sheet materials is hinged with a portion underlying the first
sheet material. As mentioned, ths exposed portion carrylng a less
tac}cy or adherent adhesive layer is adapted for releasably
engaging the plastic liner on the opposed end of the diaper when
brought into superposition. Prior to use, the adheslve layer on
the second sheet material may be hinged or folded into contact
with the non-adhesive surface of the first sheet material, which
surface then functions as a release liner protecting ~he
repositionable adhesive layer. To facilitate this release
function, ~he contact area on the backing of the first sheet
material may contain a coating of silicone or other suitable
material providing the release function. In use, the
repositionablq adhesiva is simply peeled away from the first sheet
to provide the adhesive tab for securing the diaper.
The present invention provides in a disposable article
of apparel having an inner surface adapted to be positioned
against the body and an outer surface comprising a tearable
plastic material ha~ing a surface tension no greater ~han about 33
dynes/cm, said article having secured thereto a repositionable
press~re-sensitive adheslve layer adapted for releasably engaging
said plastic material when placed in superposition therewith,
whereby ~o releasably secure said article on the body;
the improvement wherein said adhesive layer comprises a blend
of polyacrylate and tackifier characterized as being sufficiently
aggressive to secure said article on the body but being releasable
without tearing said superposed plastic material to which it is
adhered, said adhesive layer further being characterized as
possessing a 180 peel strength adhesion of from about one to
about one and a half pounds per linear inch and a probe tack of
from about 150 to abou~ 350 grams.
The present lnven~ion further provides in a disposable
article of apparel having opposed edge portions, an inner surface
adapted to be positioned against the body and an outer surface
comprising a tearable plastic material having a surface tension no
greater than about 33 dynes/cm, said article having secured to
said inner surface of one said edge portion at least one
repositionable pressure-sensitive adhesive layer adapted for
releasably engaging said plastic material of the other said edge
portion when the other of said opposed edge portions is placed in
superposition therewith, whereby to releasably secure said opposed
edge portions;
the improvement wherein said adhesive layer comprises the
free outer layer of an adhesive patch consistlng of a sheet
material carrying said repositionable adhesive layer on one
surface thereof and a permanent adhesive layer on the opposed
sur~ace, said patch being adhered to ~aid article of apparel by
means of said permanent adhesive layer, said repositionable
adhesive layer comprising a blend of polyacrylate and tackifier
characterized as being sufficiently aggressive to secure said
opposed edge pGrtions but being releasable without tearing said
superposed plastic material to which it is adhered, sald adhesive
layer further being characterized as possessing a 180 peel
%
strength adhesion of from about one to about one and a half pounds
per linear inch and a probe tack of from about 150 to 350 grams.
The present invention additionally provides a
disposable dlaper having opposed end and edge portions, a porous
inner surface or top sheet and a tearable liquid-impermeable outer
surface or back shaet compxised of a polyolefin or other plastic
material having a surface terlsion no greater than about 33
dynes/cm, a repositionable adhesive layer being positioned on said
inner surface adjacent opposed edge portions at one end thereof,
said adhesive layer being adapted for releasably engaging said
outer surface when brought in superposition therewith whereby to
secure said diaper on the body, each said adhesive layer being
characterized as being suffi.ciently aggressive to alternately
secure, release and resecure said diaper on the body a plurality
of timas, but being releasable from the adhered portion of said
tearable outer surface without tearin~, each said adhesive layer
comprising a blend of polyacrylate and tackifier possessing a 180
peel strength adheslon of from abou~ one to about one and a half
pounds per linear inch and a probe tack of from about 150 to about
350 grams. In such a diaper, preferably each said adhesive layer
comprises the free outer surface of an adhesive patch consis~ing
of a sheet material carryiny the repositlonable adhesive layer on
one surface thereof and a permanent adhesive layer on the opposed
surface, said patch being adhered to the linear surface of the
diaper by means of the permanent adhesive layer.
The invention further provides a disposable diaper
having opposed end and edge sections, an inner surface comprising
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a liquid-permeable sheet material and an outer surface comprising
a li~uid-impermeable tearable polyole~in sheet material, an
adhesive patch being secured to sald inner surface ad~acent to
each of the opposed edges at one of said end sec~ions, each said
patch consisting essentially of a support sheet having on one
surface thereof an adhesive layer aggressively adhering said patch
to said inner surface, the opposed surface of said patch carrying
a repositionable adhesive layer adapted for releasably enga~ing
said outer surface when said diaper is folded medially to bring an
area of said outer surface in superposition therewith, said
repositionable adhesive layer being characterlzed as being
sufficiently aggressive to engage said superposed outer surface to
secure said diaper on the body but being releasable therefrom by
pulling without tearing said outer sur~ace to which it was
adhered, said adheslve layer comprising a blend of polyacrylate
and tackifier.
As will be appreciated, dia~per closure systems such as
the aforementioned repositionable tapes must possess certain
criteria for optimum efficiency. On the one hand, they must
possess the requisite peel adhesion, shear strength, and stability
on aglng to secure the diaper. On the o~her hand, this adhesion
must not be so great as to ~ear the plastic liner when the ~ape is
peeled therefrom. Xn essence, the adhesive must ade~uately secure
the diaper while a~ the same time being alternately releasable and
re-attachable a plurality of times without tearing the attachment
area of the plastic liner.
Throughout the evolution of diaper closure systems from
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safety pins and the like, this tearing of the plastic attachment
area has remained a constant problem, even though it may occur in
only a small number of cases. In fact it is still regarded as the
singlemost problem in the disposable diaper industry today.
Consequently a "full proof" closure system is still needed.
In an effort to satisfy this need, various alternatives
to the current tape systems have heretofore been considered. For
example, U.S. Patent 3,840,013 discloses a disposabla diaper
employing Velcro* fasteners. However, its manufacturing costs are
too great to be considered as a viable substitute.
The present invention is directed to the aforementioned
problem of providing a releasable or reposltionable closure system
which will severely limlt if not entirely preclude incidents of
tearing, which closure system is both elegant and compatible with
the existing diaper-makiny machines.
a~ N OF ~ ~L~Y~E~
In accordance with the present invention, a novel
adhesive system is provided for securing superposed portions of a
disposable diaper or other article of apparel. This novel
adhesive system comprises adhesive patches consisting essentially
of a single sheet material coated on each surface with an adhesive
layer. The adhesive layer on one surface, which may be a
pressure-sensitive, heat- or water-activated adhesive, is adapted
to secure the patch permanently. The adhesive layer on the
opposed surface possesses appreciably less peel strength and is
characterized as being a pressure-sensitive adhe~ive adapted for
releasably engagin~ a superposed portion of the article in such a
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manner that these opposed surfaces are secured together so as towithstand stress forces incidental to normal usa~e, but may be
manually separated without tearing or rendering. The invention
will be best understood by re~erence to the following detalled
description taken in conjunctlon with the accompanying drawing.
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BRIEF DESCRIPTION OF D~ GS
Figure 1 is a top plan view of a conventional. disposable
diaper containing the novel adhesive fastening system of this
invention;
Figure 2 is a diagramatic view of the adhesivé system; and
Figure 3 is a perspective view of the diaper of Figure 1
folded mediall~y.
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DETAILED DESCRIPTION OF THE INVEN~ION
Although appllcable to other articleæ of apparel as
well, the present invention is particularly directed to disposable
diapers and will accordingly be described in detail by reference
thereto.
As is well known, the disposable diaper market
constitutes a huye and highly competitive industry. Nevertheless,
virtually all disposable diapers currently commercially available
are substantially similar in structure and design.
Generally, they are of an hour glass configuration
adapted when folded medially to engage the lower torso with the
legs extending from the curved portion.
In their simples~ form, the disposable diapers may
consist of a ~wo-piece structure: an inner porous material
adapted ~or absorbing and retaining body fluids and wastes; and an
outer liquid-impermeable liner, usually a polyolefin sheet
material such as polyethylene. However, in their commercial form,
d1sposable diapers are generally oi a three-piece s~ructure: an
inner liner or so~called top sheet of a non-woven material such as
polyethylene, polypropylene, a polyester and the like an outer
polyolefin liner or so-called back ~heet; and sandwiched
therebetween, the porous, absorbent material, generally referred
to in ~he art as "flu~f pulp", "wood fluff", or simply as "pulp".
The so-called diaper closure means for securing the
diaper in place also are all essen~ially similar with the
currently available products. To obvlate the need for safety pins
and the like, disposable diapers of the current generation
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generally emp].oy an adhesive tab system intended to be able to
releasably ent~age the diaper for closure a plurality of times,
thereby permil;ting re-adjustment and/or re diaperlng before the
d.laper is to be discarded.
Generally these adhesive tabs can be described as
containing one adhesive layer adapted for permanently securing the
tab to one portion of the diaper and a second "repositionable"
adhe~ive layer which is less tacky and wh1ch is lntended to
releasably engage the plastic outer liner to hold the diaper in
place on the body.
Although there are more than 150 U.S. Patents directed
to various tab structures for disposable diapers, the closure tabs
currently employed generally constitute two separate elements: a
first sheet material carrying the permanent adhesive layar; and a
second sheet ma~erial carrying the repositiona~le adhesive layer.
This second sheet material is secured ir~ place by a portion
thereof being placed under and adherqd to the first adhesive
layer, the unsecured remaining portion being flexible to
constitute a foldable tab.
~hile not intended to be a f~lly comprehensive survey o~
the patent literature pertaining to the state of the art with
respect to adhesive ~abs employed with disposable diapers, the
following patents are nevertheless considered to be illustrative:
4,378,800; 4,211,226; 4,182,333; 4,100,921; 4,066,0~1; 4,055,182;
4,047,530; 4,047,529; 4,047,528; 4,029,098; 3,948,268; 3,948,267;
3,948,258; 3,931,666; and 3,893,460.
While disposable diapers of the foregoing description
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are en~irely satisfactory most of the time, as mentioned earlier,
lt is universally accepted that the major problem to overcome is
the tearing of the plastic liner when the diaper is opened. Once
this liner ls torn, revealing the underlying porous material,
re-closure is difficult and awkward to accomplish.
The present invention provides an elegant solutlon to
this problem of tearing while at the same time simplifying
construction, which in turn affords obvious significant
manufacturing cost advantages.
With reference now to Figures 1 and 3 of the drawings,
the diaper 10 of this invention is shown to be of per se known
configuration havlng ends portions 12, 1~ and edge portions 16, 18
definin~ an hour glass-shaped article having an inner surface 20
adapted to engage the torso and an outer surface 22. In its
simples~ form, inner surface 20 may comprise the surface of an
absorbent, porous material. However in conventional disposable
diapers currently on the market, inner surface or top shee~ 20
comprises a liquid-permeable flexible sheet material, outer
surface or back sheet 22 comprises a liqu~d-impermeable sheet
ma~erial, e.g. a polyolefin such as polyethylene, the a~sorbent
material, e.g. layers of wadding, wood fluff and the like belng
sandwiched therebetween. As an example of disposable diapers as
described above, mention may be made of those disclosed in U.S.
Patent 4,443,512 issued to Delvaux.
The novel closure sys~em of this invention is shown to
comprise a pair of adhesive patcheæ 24 secured ~o the inner
surface 20 adjacent opposed edges of end portion 12. While
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patches 24 are shown to be generally rectangular in shape, they
may if desired be of other configuration e.g. circular. However
for optimum closure efficiency, it is preferred that they be
generally rectangular in configuration and have a surface area on
the order of one to two square inches. A typical patch may, for
example, be on the order of 1 inch by 1.5 inches.
As shown in Eigure 2, patch 24 consists essentially of a
sheet material 26 coated on either side with adhesive layers 28,
30. Adhesive layer 2B is a permanent adhesive adapted to secure
the patch to porous ma~erial 20; whlle adhesive layer 30 is a
repositionable adhesive adapted ~o releasably engage the other
plastic liner 22 adjacent end portion 14 when the diaper is folded
into place on the body. While not critical to the invention, it
will be appreciated that a release liner or sheet 32 could, if
desired, be provided over layer 30 to prevent premature and
unwanted contact of the adhesive with a substra~e. As
illustrated, release liner 32 is shown to be of slightly greater
longitudlnal dimension for ease of gxipping for removal.
Alternatively, lt is envisioned that the diaper could be packaged
in its folded position with patches 24 adhered to the back sheet.
In the embodiment illustra~ed in the drawing, the
closure system is shown to consist of a pair of opposed pat~hes
24. Obviously modifications of design are permissible and are
accordingly herein contemplated. For example, two or more
patches, e.g. of smaller configuration, could be provided adjacent
each of opposed edges 16, 18. In like manner, a single tape 24
could extend the width of end portion 12 ~o edges 16, 18 with only
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the portions thereof closest to the respective edges bearing an
adhesive surface. However, the structure shown in the drawing is
entlrely sufficient for its intended purposes and is considered to
be the most feasible from a cost and manufac~uring standpoint.
With respect to the patches themselves, which constitute
the essence of the invention, support sheet 26 may be any of the
per se known materials for carrying adhesive layers and the like.
I~ may for example be a plastic material such as cellulose acetate
or a polyester such as polyethylene terephthalate, the latter
being particularly efficacious. While the thickness of the
support material is not critical, sheet materials on the order of
a quarter of a mll thick have been found to be entirely
satis~actory.
In like manner the thlcknesses of the respectlve
adhesive coa~ings 28, 30 may vary and may be the same or
d~fferent. The selection of ~he particular thicknesses will be
readily ascertainable by those skilled in the art. However, by
way of illustration, they may be on the order of one to two mils
(dry coating).
Parmanent adhesive 28 may be any adhesive which will
aggressively bond to the non-woven inner surface of the diaper.
On the o~her hand, adheslve layer 30 must be repositionable. As
used herein, the term "repositionable" means the ability to be
positioned for closing or sacuring the diaper and then releasable
for opening the diaper a plurality of times during at least the
normal and customary usage of the diaper. In other words, it
need not possess the characterist~ C5 of being repositionable an
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infinite or counkless number of times. In the normal usage, it ls
contemplated that it may be necessary to re-adjust the diaper a
few times when putting i~ on inltially and then to open it a few
times for inspectlon, e.g. to see lf baby is dry. ~ccordingly, in
the practice of this invention, it is contemplated that the
adhesive closure coating should preferably be repositionable at
least six times. That is to say, the pressure-sensitive adhesive
for releasably engaging an opposed portion of the diaper should
preferably maintain the requisite tackiness and adhesion to permit
opening and securing the diaper on the order of at least slx times
and, most preferably, an even greater number of times.
As is well understood in the adhesive art, there is no
truly efficient universal adhesive which will provide effective
bonding to all substrates. Accordingly, in order to provide the
closure system accomplishing the objectives to which this
application is directed, the combinat;ion of substrate and
repositional adhesive must be selecte!d consistent with the
objectives, as previously discussed.
Since the back sheet is conventlonally a polyolefin,
logic lndicates that one starts with the given that the substrate,
i.e. the surface of ~he back sheet to which the repositionable
adhesive is to engage, is a polyolefin or a material which is
similar to a polyolefin in the sense that its cohesive properties
or behaviour with respect to the repositionable adhesive are
essentially the same as a polyolefin. Useful alternatives to
polyolefins may be described as materials having a low energy
surface, more particularly, a surface tension or energy on the
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order of 33 dynes~cm or less.
Accordingly, in ~he practice of the present invention,
the surface of at least that portion of back sheet 22 which is to
releasably engage the repositionable adhesive will consist of a
polyolefin or a material exbibiting a cohesion with respect to the
repositionable adhesive coatlng which i5 similar to polyolefins.
Typically, the back sheet comprises a single continuous
sheet material. However, it is anvisioned that in some instances
the back sheet may comprise a first sheet material having a second
sheet material laminated to its edge portions. For ins~ance, it
is understood that a disposable diaper 15 currently being test
marketed in which a perforated breathable leg cuf~ is secured at
either edye of the back sheet.
Critical ~o the present invention is providing a
repositionable adhesive having the previously described
releasability from the back sheet. The invention is accordingly
predicated in part upon the recognition by the Applicant that
polyacrylates as a class release extremely well from polyolefins,
rather than aggressively bonding, as do the rubber-based
~0 adhesives. Since the polyacrylates themselves will not provide
the necessary adhesion and peel strength, tackifiers need
therefore be added to provide the desired adhesion for securing
the diaper in its "closed" position on the body.
Aacordingly, in the practice of the present inven~ion
the repositionable adhesive layer comprises a polyacrylate
adhesive base containing tacXifiers or adhesive agents in amounts
sufficient to provide the desired balance of cohesion and
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releasability, that is, an adhesion which is sufficlently
aggressive to maintain or secure the diaper in the closed position
on khe body while at the same time malntaining the releasability
so that the dlaper may be opened without tearing, the adhesive
layer further being characterized as permittiny repeated
fastening, unfastenings and refastenings without losing its
ability to retain the diaper in the fastened or closed position.
To those skilled in the art of adhesives, the physical
prerequisites and characteristics desired for an adhesive layer
are generally more relevant information than a detailed discussion
of the chemical composltion, e.g. monomers~ tackifiers, filler and
o~her addenda which may be in the adhesive formulation. In other
words, given the desired physlcal prerequisites and functions
contemplated for an
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adhesive coating, one skilled in the art may often devise the
necessary formulations without the e~ercfse of inventive
faculties.
Accordingly, the respective adhesive 28, 30 will first be
discussed in terms of the physical parameters and function.
As mentioned, permanent adhesive layer 28 should be an
aggressive adhesive for securing the patch to the top sheet.
More specifically, the adhesion to the top sheet (180 peel
strength) should be on the order of at least three pounds per
linear inch; and the probe tack in grams should be on the order
of at least 550.
On the other hand, repositionable adhesive layer 30 should
possess an adhesion generally on the order of one third that of
the permanent adhesive, e.g. on the order of one to one and a
half pounds per linear inch; and it should exhibit a probe tack
of at least 150 grams but no greater than about 350 grams.
In a standard lap shear test (one kg. at 150F), the lap
of a l" x 2" strip should hold for in excess of one hundred
hours.
The adhesive compositions which may be employed for
permanent adhesive layer 28 per se comprisa no part o~ this
invention. In general, they include those adhesives known in
the art which will bond aggressively to the substrate, e.g.
polyethylene, comprising the surface of the top sheet.
Rubber-based adhesives are particularly efficacious. As a
further illustration of suitable compositions for permanent
adhesive layer 28, mention may be made of per se known resin
and plasticizer modified triblock copolymers such as Kraton
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1107 (trademark of Shell Oil Company for a styrene-lsoprene-
styrene triblock copolymer), Kraton 1102 ~trademark of Shell Oil
Company for a styrene-butadiene-skyrene triblock), and Kraton G
(trademark of Shell Oil Company); resin and plastlcized copolymers
of styrene-butadiene; natural rubber adhesives; polyacrylates
possessing ~he re~uisite high adhesion to the top sheet substrate,
etc.
As examples of suitable compositions for the
repositionable adhesive layer 3Q, mentioned may ba made of the
class of polyacrylates which can be described as possessing yood
shear strength suitable for removability from the back sheet, e.g.
from polyolefin films. Such a high shear polyacrylate should of
course po~sess good removability from the polyolefin or other
substrate for the back sheet. In order to achieve the proper
balance of adhesion and shear strength, tacklfiers, e.g. rosin
ester, may be incorporated to modify the adhesion level upward
without impairing the removability withou~ tearing level. By way
of further illustration~ useful polyacrylate adhesives should have
suficient molecular weight, e.g. on the order of at least
500,000, to exhibit sufficient shaar strength to meet the cohesive
requirement d&rived from the copolymerization of acrylic monomers
alone or with other non-acrylic monomers. As examples of useful
acrylic monomers, mention may be made of those heretofore used in
the adhesive industry, e.g. ethyl acrylate, 2-ethylhexyl acrylate,
isooctyl acrylate, n-butyl acrylate, ethoxyethyl acrylate~ etc.
Other monomeric materials which may be polymerized along with one
or more acrylic materials, e.y. ~o form a terpolymer, include
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vinyl acetate, acrylonitrile, ethylene, and acrylic acid.
As is understood in the art, thickeners may be found to
be advisable or necessary to facilitate coating the adhesiva
layer(s). Suitable thickeners, e.g. acrylics such as copolymers
of acryllc acid and another monomer are well known, commercially
available and per se comprise no part of the present invention.
The following examples illustrate the preparation of the
novel adhesive system of this invention.
EXAMPLE 1
A high molecular weight polyacrylate adhesive
composition comprising, (a) 100 grams of an aqueous dispersion
(approximately 55% solids content) of a tetrapolymer of 80.0 parts
2-ethylhe~yl acrylate, 15.5 parts ethyl acrylate, 2.5 parts of
acrylonitrile and 2.0 parts of acrylic acld; (b) 20 grams of a
tackifier, FORAL 105-50WK (trademark of Hercules Incorporated for
a 50% solids-content anionic aqueous resin dispersion prepared
from the pentaerythritol ester of hydrogenerated rosin, visc.
10-20 cps at 25C, pH 8-10); and (c) 0.6 grams of styrene-acrylic
acid copolymer thickener 68-710 (Reichold Chemicals Inc.), was
coated on one sur~ace of a double release liner, a supercalenderefl
Kraft paper having a silicona release liner on either side
(obtained from Schoeller Products under the trade designatlon
R-coat 65ISC 60 S~5). The coating was then dried at 160F for
about flve minutes ~o provide a reposltionable pressure-sensitive
adhesive layer approxlmately 1.6 mils thick (when dry). A quarter
mil Mylar* (du Pont) polyester carrier shaet was then pressure-
lamlnated to ~he drled adhesive layer by passage through a pair of
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superposed rubber pressure rollers. After drying, an aggressive
adhesive layer was applied to the opposed surface of the Mylar
carrier by coating a layer of DURO-TAK 36-6129 (trademark of
National Starch and Chemical Corporation for a pressure-sensitive,
rubber-based solution, 55% solids, visc. 3,000 cps.) and then
drying at 160F for about five minutes to provide an adhesive
layer approximately 1.6 mils thick. The resulting ~wo-sided tape
was then cut into one-inch strips and rolled up with the
aggressive adhesive layer adjacent the ree release liner.
~XAMPLE 2
Example 1 was repeated, employing 100 grams a
polyacrylate adhesive formulation according to Example 1 of United
States Patent 4,20~,023 issued to Witt May 20, 1980 to which was
added 15 grams of FORAL 105-50WK and 0.6 grams of 68-710
thickener.
Adhesive patches prepared in accordance with the
foregoing illustrative examples were tested on commercially
available disposable diapers, as shown in the drawings. In these
te~ts, patches approxlmately 1" x 1.5" were applied as shown wlth
the aggressive adhesive bonded adjacent opposed edges at one end
of the top sheet and the release liner was removed to reveal the
repositionable adhesive layer. They were subjected to repeated
openings and closings by attachment to the back sheet far in
excess of what would be required in usage, e.g. twenty ox more
tlmes. In every instance they exhibited sufficiently aggressive
bonding to secure the diaper and in no instance was any teari.ng of
the back sheet evidenced.
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In ~he foregolng descrip~ion of the invention, the
adhesive system has been described as what may be termed a two-
faced adhesive patch, i.e. a laminar structure wlth the ~arrier or
support element sandwiched between two outer adhesive layers, one
being aggressive for permanent bonding to the top sheet of the
disposable diaper, the outer being a reposltionable adhesive for
releasably engaging the back sheet.
Because of its slmplicity in manufacture, this structure
is preferred. However, it is contemplated that the adhesive
system may be in the form of tabs or "ears" extendable beyond the
periphery of the diaper body such as the various configurations of
this description described in the patent literature.
While reference has been made throughout to disposable
diapers, the articles to which this invention is primarily
directed, it will further be appreciated that the invention is
also applicable to various other inexpensive and/or disposable
articles where reposltionable adhesives are desired. For example,
disposable li~uid-impermeable paint garments are known in the art.
They may be in the form of jackets, smocks and the like for use in
the home, laboratory, commercial establishments such as auto body
shops and the like.
From the foregoing description it will thus be seen that
the present invention solves a long-felt need with disposable
diapers and the like by providing a simple, inexpensive and highly
efficacious adhesive system for releasably securing the article.
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Since various changes may be made without departlng from
the spirit and scope of the invention as recited ln khe appended
clalms, lt is intended ~hat the foregoing descriptlon be taXen as
lllustrative and not in a limiting sense.
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