Background of the Invention
[0001] Pads of sheets of flexible material, e.g. note paper are padded by being provided
on their backs with so-called repositional (or repositionable) adhesive. The terminal
sheet in the pad usually lacks a backing of adhesive, and often is made of a sheet
which is noticeably different in appearance (e.g. a padded stack of canary yellow
sheets terminated by a kraft brown backing sheet bearing a manufacturer's name and
logo on its exterior face). Sheets which are successively the top sheet may be successively
written upon, successively peeled off and repositionally stuck on another surface,
such as on a page of a book, on a refrigerator door or on a telephone handset.
[0002] However, in the usual instance, although the individual sheets are designed to be
removably adhered to a surface, the pad is not designed to be adhered to anything
so it may easily become misplaced. In addition, because such pads usually are quite
small in lateral dimension, writing on the top page may require a two-handed operation,
one hand to hold the pad to keep it from moving and the other to hold the pen or pencil.
Two procedures have been devised heretofore for alleviating these problems. One, adopted
by a major manufacturer of such pads, is to supply a relatively large and heavy container
for a pad, through the open top of which the top sheet of the pad is accessible for
being written upon. At least partly in testimony to the lack of inclusiveness of that
solution, another has arisen, seemingly at the user level And that is for the user
to peel the backing sheet off of the pad and then to use the strip of repositional
adhesive on the back of the thereby-exposed last sheet of the pad to stick the pad
to a surface, such as to a telephone table near the telephone, or to a wall near the
telephone, to the refrigerator door, or the like. However ingenious, this last-mentioned
solution has shortcomings also. Most important is that the strip of repositional adhesive
on the back of the last sheet, not having been meant to hold the weight of the whole
pad, but only of a single sheet, lets go. Then, the pad slides or falls and may become
lost behind a piece of furniture, or the exposed strip of repositional adhesive may
get dusty or attract enough food crumbs, dog hairs or whatever may be on the floor,
so that its already deficient power to firmly stick the whole pad to a surface is
lost, necessitating at the least, that the rear sheet be peeled off and thrown away
in order to expose a new strip of repositional adhesive. Needless to say, this technique
results in the pad being used from both ends (one end by being written on and peeled
off, and the other by getting dirty and being peeled off).
[0003] The present invention was devised to overcome the above-mentioned shortcomings of
existing ways and means for fixing the position of a pad of adhesively back-coated
repositional sheets of note paper or the like.
Summary of the Invention
[0004] A pad of sheets of flexible material, e.g. note paper, has each sheet but the last
one provided on its rear surface with a band, spot or other region of lightly-tacky
adhesive which allows the sheet to be peeled off and pressed onto another surface
to removably hold that sheet to a surface, e.g. for bearing a message. The back of
the last sheet is provided with an adhesive area having a significantly stronger bonding
strength by the adhesive itself being stronger or covering a larger area, e.g. so
that the pad, once stuck to a surface, such as that of a wall, will stay put, throughout
the life of the pad, and until intentionally removed.
[0005] The principles of the invention will be further discussed with reference to the drawings
wherein preferred embodiments are shown. The specifics illustrated in the drawings
are intended to exemplify, rather than limit, aspects of the invention as defined
in the claims.
Brief Description of the Drawings
[0006] In the Drawings
Figure 1 is a perspective view of a pad of the prior art type; and
Figure 2 is a longitudinal cross-sectional view showing that pad in use.
Figure 3 is a longitudinal sectional view of a pad of the present invention, showing
the pad being readied for use;
Figure 4 is a longitudinal sectional view similar to Figure 3, showing the new pad
in use;
Figure 5 is a longitudinal sectional view similar to Figure 4, showing a top sheet
of the pad being pulled off for repositioning elsewhere; and
Figure 6 is a longitudinal sectional view similar to Figure 5, showing a variation
in the extent of the adhesive provided on the back of the last sheet.
[0007] (In the drawing figures, thickness has been exaggerated for convenience in illustration.)
Detailed Description
[0008] A prior art pad of repositional sheets is illustrated at 10 in Figures 1 and 2. This
pad comprises a plurality of sheets 14 of flexible material, such as note paper, arranged
in a stack. Each sheet 14, except the bottom (or backing) sheet 16 has been provided
on its back with at least one strip, band, region, area or the like 18, continuous
or discrete, of a lightly-tacky adhesive. The adhesive 18 most frequently is provided
in a narrow band occupying, e.g., the top approximately twenty percent of the back
surface 20 of each respective sheet, adjoining the top edge 22 of the sheet, which
coincides with the top edge of the pad. The backing sheet 16 may be similar in composition
to the sheets 14, although it often is a different color, in order to help consumers
to avoid attempting to use the wrong side of the pad.
[0009] Thus, in normal intended use, the pad 10 rests on a surface 24 with no adhesive between
the back surface 26 of the backing sheet 16 and the surface 24 on which the pad is
supported. In a known prior art use which has been referred to above, the pad may
be stuck to the surface 24 (in an unsatisfactory way), by peeling off the backing
sheet 16 and using the band of repositional adhesive 18F on the newly-exposed last
sheet 14F to try to temporarily adhere the pad 10 to the surface 24.
[0010] Moore Business Forms, Inc. manufactures and/or distributes a type of prior art pad
as shown in Figures 1 and 2, under the trademark Note Stix®.
[0011] Now comparing Figures l and 2 with Figures 3-6, the pad 10′ of the present invention
may comprise exactly the same elements as the prior art pad 10, except for the nature
of the adhesive used in the coating on the last sheet in the stack. Accordingly, like
parts have been given like numerals, but primed ones.
[0012] In the pad 10′ of the present invention, the band of adhesive provided at 18F′ is
not merely the same in composition, area, thickness and degree of tackiness as the
bands of adhesive 18′. Instead, due to any combination of differences in composition,
area, thickness and degree of tackiness, it has substantially greater holding-power
than do the individual bands 18′. As a result, the backing sheet 16′ may need to be
a release-coated sheet, e.g. a sheet of paper coated with wax, a polyethylene terephthalate
varnish or the like so as to permit the backing sheet 16′ to be peeled-off so that
the pad 10′, can be firmly stuck, via the adhesive 18F′ to a surface 24.
[0013] The adhesive 18F′ may itself be a layer of double-sided adhesive tape, such as that
marketed by Moore Business Forms, Inc. under the name "Transfer" tape. In such a case,
the removable backing sheet 16′ need be coextensive only with the strip of double-sided
adhesive tape and not necessarily coextensive with the rear surface facial area of
the last sheet 14F′ of the pad.
[0014] Of course, an adhesive which has closer, if not identical holding power to that used
for the strips 18′ can be used for the strip 18F′ if the latter covers a greater area
than does each of the strips 18′, e.g. as is illustrated at 18F˝ in Figure 6.
[0015] By way of further exemplifying the preferred embodiment, an example will be given:
[0016] In a practice of the invention, a pad 10′ is constructed of the materials and by
the techniques currently used to produce Note Stix pads, except that the adhesive
used at 18F′ on the last sheet, instead of being merely the same as used at 18′, and
the backing sheet 16′ were provided by the Transfer tape product referred to above.
The standard test used at Moore Business Forms, Inc. for the holding strength of a
pressure sensitive-type adhesive for repositional paper sheets is: 90 DEGREE peel
test pulled at 12 inches per minute from stainless steel, sample size 1˝ x 8˝. Rolled
four times with a 4 lb. roller.
[0017] According to that test, the holding strength of the bands of adhesive 18′ is typically
in the range of: .2 - 4.0 ounces per inch.
[0018] Also according to that test, the holding strength of the band of adhesive 18F′ is
typically in the range of: .2 - 40.0 ounces per inch. (Note: low strength would apply
at high area coverage.)
[0019] In the variation which has been described with reference to Figure 6, in which the
adhesive used at 18F˝ may be the same as that used at 18′ but covers a broader area
of the back of the respective sheet, the adhesive used typically is that currently
used for making Note Stix pads, but whereas the adhesive 18′ covers a band occupying
in the range of: 1 - 50 percent of the rear face of each respective sheet, the adhesive
18F˝ covers a band occupying in the range of: 1 - 100 percent of the rear face of
the last sheet.
[0020] The term 'band' of adhesive has been used loosely (i.e. generically) in the description
herein and should not be taken to necessitate that the area to which any adhesive
is applied be of any particular shape, or that it consist of a single, continuous
region.
[0021] It should now be apparent that the pad of repositional adhesive-backed sheets with
pad-backing of stronger adhesive than used on backs of other sheets in pad as described
hereinabove, possesses each of the attributes set forth in the specification under
the heading "Summary of the Invention" hereinbefore. Because it can be modified to
some extent without departing from the principles thereof as they have been outlined
and explained in this specification, the present invention should be understood as
encompassing all such modifications as are within the spirit and scope of the following
claims.
1 A pad of repositional adhesive-backed sheets, comprising:
a stack of sheets of flexible material including a last sheet backed by a backing
sheet;
each sheet but said last sheet and said backing sheet being provided on a rear surface
thereof with a band of lightly-tacky pressure-sensitive adhesive which allows the
sheet on which it is provided to be peeled from the pad and pressed onto another surface
to removably hold that sheet to that other surface;
said last sheet having a rear surface thereof provided with a band of adhesive having
a substantially stronger bonding strength considering its total area relative to the
total area of each of said bands of lightly tacky pressure-sensitive adhesive, than
that of each of said bands of lightly tacky pressure-sensitive adhesive;
said backing sheet being peelably removably adhered to said band of adhesive having
a substantially stronger bonding strength.
2 The pad of repositional adhesive-backed sheets according to claim 1, wherein:
said band of adhesive having a substantially stronger bonding strength has a substantially
stronger bonding strength per unit area on said rear surface of said last sheet than
does each of said bands of lightly tacky pressure-sensitive adhesive.
3 The pad of repositional adhesive-backed sheets accordiing to claim 1 or 2 wherein:
said band of adhesive having a substantially stronger bonding strength covers less
than all of the total area of the rear surface of said last sheet; and
said backing sheet removably covers all of said band of adhesve having a substantially
stronger bonding strength.
4 The pad of repositional adhesive-back sheets according to claims 1, 2 or 3 wherein:
said backing sheet covers less less than all of the total area of the rear surface
of said last sheet.
5 The pad of repositional adhesive-backed sheets of claim 1, wherein:
said band of adhesive having a substantially stronger bonding strength covers a substantially
greater percentage of the rear surface of said last sheet than does each band of said
lightly tacky pressure-sensitive adhesive of the rear surface of each respective sheet.
6 The pad of repositional adhesive-backed sheets of claim 5, wherein:
said band of adhesive having a substantially stronger bonding strength per unit area
than that of the lightly tacky pressure-sensitive adhesive provided on the rear surfaces
of those of said sheets in said pad which overlie said last sheet.
7 The pad of repositional adhesive-backed sheets according to any of the preceding
claims wherein:
said flexible material is paper.