Extractive transfer diaper tab means

A diaper tab stock of only two substrates provides diaper tabs that are linerless, that are refastenable, and that are of the relatively strong Y-configuration type. When tabs made from the stock are closed and reopened in the normal manner of use, part of one adhesive layer is "extractively transferred" from between the two substrate layers to another part of the diaper to thereby present a "fresh" adhesive face for subsequent refastening, such transfer occurring in the absence of any transfer of a substrate. The two-substrate construction may be formed by folding an appropriately coated originally single layer of substrate material.

This invention relates to web constructions of tab stock of the kind 
adapted to be supplied to a diaper manufacturer and to be separated by the 
manufacturer into individual linerless refastenable diaper tab 
constructions of Y-configuration and applied to individual diapers, 
usually two tabs to a diaper. By "linerless" is meant the absence of any 
adhesive-protecting liner of release paper or the like that has to be 
separately disposed of by the person applying the diaper. By 
"refastenable" is meant a diaper tab which can be fastened by exposing and 
applying an adhesive face and refastened by exposing and applying a 
"fresh" second adhesive face. 
Linerless refastenable tab constructions are shown in the following: 
______________________________________ 
3,951,149 4/1976 Ness et al. 
Johnson & Johnson 
Appln. Serial No. 
Filed Richman Avery International 
624,870 10/23/75 et al. Corporation (common 
assignee) 
Appln. Serial No. 
Filed Nemeth Avery International 
770,646 2/22/77 Corporation (common 
assignee) 
______________________________________ 
However these tab constructions all require at least two substrates to 
provide for refastenability. One substrate is associated with the 
initially exposed adhesive and the other substrate is associated with the 
subsequently exposed "fresh" adhesive. The substrate associated with the 
initially exposed adhesive is either not originally co-extensive with the 
other substrate to thereby allow the former to transfer along with the 
originally exposed adhesive (Ness), or is slit to allow part of such 
first-mentioned substrate to transfer along with the originally exposed 
adhesive (Richman, Nemeth), the referred-to transfer in each case being 
from the part of the diaper the mentioned elements are first associated 
with to another part. 
Where a refastenable tab of Y-configuration is provided, as in the second 
of the above items, three tab substrates are required, two for the 
refastenable feature, and an additional one for the Y-configuration 
feature. By "Y-configuration" is meant a tab configuration in the shape of 
a Y whose two legs and stem all bear adhesive, the legs being adapted to 
be fastened by the manufacturer to both sides of one part of a diaper 
adjacent an edge, and the stem being adapted to be fastened to another 
part of the diaper by a person applying the diaper. Tabs of 
Y-configuration provide increased or double strength where it is most 
needed--at the diaper-to-tab connection which receives the strain when the 
person applying the diaper pulls on the tab to draw the diaper tight 
before closing it. 
The present invention provides a linerless refastenable diaper tab of 
Y-configuration which is so arranged as to require only two substrates 
even though both the refastenability and Y-configuration features are 
included. This is accomplished by providing for successive partial peeling 
back between a certain adhesive layer and two different substrates between 
which the adhesive is sandwiched. The arrangement is such that after the 
first partial peeling back and upon the first closing of the diaper by 
conventional manipulation of the tab by the user, adherence to the diaper 
of the adhesive face exposed by the first partial peeling back assures 
exposure of the second adhesive face during a subsequent second partial 
peeling back when the diaper is first reopened. The two substrates may be 
originally coextensive but neither need be slit. 
The portion of the adhesive layer that is associated with peeling back (the 
peelback portion) separates or breaks from the portion that is not so 
associated as the second peeling back is completed, allowing the reopening 
of the diaper to be completed. At this point the peelback portion of the 
adhesive layer in question is left deposited on one portion of the diaper 
and completely disassociated from the remainder of the tab structure while 
the other portion of such adhesive layer remains between and permanently 
associated with the two different substrates between which it was 
initially sandwiched, continuing to fix them together. 
All portions of the two substrates remain at all times with the part of the 
diaper on which they are originally mounted even though the adhesive 
originally between them at the peelback portion becomes completely 
disassociated from such part of the diaper when the diaper is opened. 
Consider the substrate-adhesive-substrate construction just discussed as a 
"sandwich" in which the substrates are the "bread" and the adhesive is the 
"meat." All the "bread" and roughly half the "meat" remains on one part of 
the diaper while the other half of the "meat" is extracted or is taken out 
from between the "bread" and transferred or put on the other part of the 
diaper in the course of closing and reopening the diaper. This type of 
extractive transfer of part of an adhesive layer from between two 
substrates which remain permanently joined by the remaining part of the 
adhesive layer is believed to be completely novel in diaper closures.

As seen in FIG. 1, the web construction comprises a first substrate 11, 
extending, transversely to machine direction, along first and second 
length portions 41 and 42 respectively. The first substrate bears first 
substrate adhesive 21 on its underside. Preferably, the adhesive 21 stops 
short of the free end of the first substrate 11 at the second length 
portion as seen in FIG. 1. 
A second substrate 12 also extends along the length portions 41 and 42. The 
second substrate bears the second substrate adhesive 22 on its underside. 
The second substrate adhesive 22 extends along the first and second length 
portions 41 and 42, as shown. 
First and second release means 31 and 32 are provided for the first 
substrate adhesive 21 and are located respectively above and below the 
first substrate adhesive at the second length portion 42, as seen in FIG. 
1. The first length portion 41 is substantially free of both the first and 
second release means 31 and 32. The first release means 31 is on the 
underside of the first substrate 11 and the second release means 32 is on 
the topside of the second substrate 12. The second release means 32 is 
selected to provide relatively easier release than the first release means 
31. 
In order that the stock shown in FIG. 1 may be self-wound, a third release 
means 33 is provided on the topside of the substrate 11. The third release 
means 33 is also selected to provide relatively easier release than the 
first release means 31. 
The construction in the form described and shown in FIG. 1 can be supplied 
to a diaper manufacturer as a self-wound roll of diaper tab stock. The 
diaper tab manufacturer cuts the roll of diaper tab stock transversely and 
folds the first and second length portions around the edge of the diaper 
D, as seen in FIG. 2, applying the second substrate adhesive 22 to the 
diaper to anchor the tab in mounted condition. The first substrate 
adhesive 21 remains positioned between the substrates 11 and 12 at the 
length portion 42 as well as at the length portion 41. 
As previously indicated, the invention involves extractive transfer of the 
second length portion of the adhesive layer 21 from between the substrates 
11 and 12 as an incident of the normal usage of the mounted tab by a 
parent who fastens and then unfastens the diaper. Thus the second length 
portion 42 of the adhesive layer 32, which is between the substrates 11 
and 12 as seen in FIG. 2, is subsequently extracted from between the two 
substrates and away from both of them to be transferred to another part of 
the diaper, as seen in FIG. 4. 
Thus, when the diaper is first being applied on an infant, the second 
length portion of the substrate 11 is unfolded. Because the second release 
means 32 provides a relatively easier release than the first release means 
31, the first substrate adhesive 21 peels back with the substrate 11 to be 
thereby exposed at face 51 for joinder to another part of the diaper when, 
as seen in FIG. 3, the diaper is fastened by the tab. 
When the diaper is subsequently unfastened by peeling back the second 
length portion of the substrate 11 from the portion of the diaper (the 
leftward portion of the diaper as seen in FIG. 4) to which it is attached, 
the first release means 31 allows the second length portion of the 
substrate 11 to peel back from the adhesive 21. When the peel-back 
progresses beyond the leftward portion of the diaper D, the peel-back 
force is no longer resisted by any part of the diaper, but only by a thin 
cross-section of the adhesive layer 21. The adhesive layer 21 thereupon 
ruptures in the vicinity of the boundry between the first and second 
length portions 41 and 42 thereby completing the transfer of the second 
length portion of the adhesive 21 to the leftward portion of the diaper D, 
i.e., the portion with which the illustrated tab was not originally 
associated when it was attached to the diaper by the manufacturer. This 
completion of transfer is illustrated in FIG. 4. Face 52 of the second 
length portion of adhesive 21 is thereby exposed for the first time and 
provides a "fresh" adhesive face for subsequent refastening of the tab. 
When the second length portion of the adhesive 21 positioned as in FIG. 4, 
the diaper may be reclosed by again positioning the second length portion 
of the substrate 11 on the fresh face 52 of the adhesive 21 so that the 
parts resume a relationship similar to that shown in FIG. 3 but of course 
with the first and second length portions of the adhesive 21 remaining 
separated by the rupture which occurs incident to the first reopening of 
the tab as above described. If it is desirable to tighten the tab 
fastening upon reclosing, as is ordinarily the case, this can be done by 
drawing the second length portion of the substrate 11 somewhat further to 
the left than the second length portion of the adhesive 21, so that these 
second length portions only partially overlap. If necessary, the righthand 
portion of the diaper shown in the drawings can be overlapped somewhat 
with the lefthand portion to accomplish this tightening, it being 
understood that the thicknesses of the tab elements shown in the drawings 
are greatly exaggerated and will not in fact interfere with overlapping. 
It will be understood that the release means, and particularly the release 
means 31, may be of any conventional type which allows peel-back release 
but strongly resists shear loads distributed over the interface between 
the release coat and an adjacent adhesive layer. Such shear loads are, of 
course, imposed by fastening tension between the two parts of the diaper 
shown in the drawing. 
The two different substrates used according to the invention may be either 
completely separate layers, or they may be separate layers hinged together 
at one edge by virtue of having been formed from a single layer folded 
over on itself in the general manner of the prior invention taught in 
Application Ser. No. 757,910 filed Jan. 10, 1977, of common assignee. The 
formation of a construction embodying the present invention from an 
originally single flat layer of substrate material is illustrated in FIGS. 
7-9. This aspect of the present invention represents an improvement over 
the just mentioned prior invention in that such prior invention does not 
teach the concept of extractive transfer of part of an adhesive layer and 
does not provide a "refastenable" diaper tab as above defined. 
The construction illustrated in FIG. 7 will be seen to be very similar to 
that illustrated in FIG. 1 except that the first and second substrates 11a 
and 12a illustrated in FIG. 7 are in fact hinged together by folding the 
initially single layer seen in FIGS. 5 and 6. 
In other respects the elements and length portions labelled in FIG. 1 may 
be substantially duplicated by those of FIG. 7. Thus in FIG. 7 are seen 
first and second substrates 11a and 12a, first and second substrate 
adhesives 21a and 22a, first, second, and third release means 31a, 32a, 
and 33a, and first and second length portions 41a and 42a. 
The single substrate layer which is to be subsequently folded into the two 
substrate layers 11a and 12a may be coated by the diaper tab stock 
manufacturer in the manner shown in FIG. 5. When the illustrated 
construction is self-wound for shipment and storage and subsequently 
unwound by a diaper manufacturer for formation into tabs, the first 
adhesive coating 21a transfers from the position shown in FIG. 5 to that 
shown in FIG. 6 because the third release means 33a provides relatively 
easier release than the first release means 31a. The diaper manufacturer 
can then fold the single substrate together to change the cross section 
from that shown in FIG. 6 to that shown in FIG. 7 and can transversely 
sever the tab stock to form individual diaper tabs. The diaper tab shown 
in FIG. 7 is then folded around the edge of the diaper (not shown) in a 
manner substantially identical to that illustrated in FIG. 2. 
The invention is not limited to the precise details of the constructions 
shown, but covers all variants based on the invention. For example, the 
second substrate adhesive 22 may be omitted at parts of the first and 
second length portions, one appropriate place for omission being in the 
region of the boundary between the length portions. The invention is 
defined by the following claims: