Note: Descriptions are shown in the official language in which they were submitted.
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"HAG TIES AND MANTJFACTLJRE THEREOF"
The present invention relates to a tie for a bag and
to a method of making a succession of ties for bags.
In the past, ties for bags have comprised lengths of
wire coated with paper or plastics with an interconnected
series of ties being provided loosely in combination with the
bags. This arrangement has a disadvantage in that the ties
and bags must be separately packed. An attempt to overcome
this disadvantage resulted in the provision of ties integral
with the material of the bags, the ties comprising lengths of
plastic disposed along one edge of the bag. However, this
neccessitated a complete modification to the bag
manufacturing apparatus.
There is a need for a tie for a bag and a method of
manufacture thereof which provides ties which can easily and
conveniently be provided in combination with the bags but
without requiring modification of the bag or its
manufacturing apparatus.
Accordingly, the present invention provides a
self-adhesive tie for a bag, the tie comprising a folded
length of tie material, an adhesive layer for adhering the
folded length to a bag, and a backing of release material
covering the adhesive layer.
In one preferred embodiment, the adhesive layer
comprises a pressure-sensitive adhesive which coats a rear
surface of the folded length. In another preferred
embodiment, the tie further comprises a support piece on
which the folded length is disposed and the adhesive layer
may be a pressure-sensitive adhesive which coats a rear
surface of the support piece.
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The support piece may in use be adhered to a bag. In
a preferred embodiment the support piece is a piece of
self-adhesive paper carried on a backing of release
material. The release material may be stripped off from the
self-adhesive support piece whereby the support piece can
then be adhered by the self-adhesive surface to a bag.
The present invention also provides a method of
making a succession of self-adhesive ties for bags, the
method comprising the steps of:-
(a) disposing a succession of folded lengths of tie
material on a web, the web including a backing of release
material and each folded length being adhered directly or
indirectly to the backing of release material: and
(b) cutting the folded lengths of tie material and
the web to form a succession of ties for bags.
Embodiments of the present invention will now be
described by way of example only with reference to the
accompanying drawings, in which:-
Figure 1 is a perspective plan view of a length of
tie material to be folded and incorporated into a plurality
of ties in accordance with a first embodiment of the present
invention;
Figure 2 is an enlarged perspective plan view of part
of the tie material of Figure 1 after having been folded:
Figures 3(a), 3(b), 3(c) and 4 illustrate a method of
making ties in accordance with the present invention:
Figure 5 is a perspective plan view of a tie for a
bag in accordance with the first embodiment of the present
invention;
Figure 6 is a perspective view of a tie for a bag in
accordance w~ah a second embodiment of the present invention:
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Figure 7 is a perspective view of a tie for a bag in
accordance with a third embodiment of the present invention
when adhered to plastics bago and
Figure 8 is a perspective view of the bag
tie/plastics bag assembly shown in Figure 7 after the tie has
been employed to seal the top of the bag.
Referring to Figure 1, there is shown a flattened
tube 2 of plastics sheet material, such as polyethylene,
which is intended to form the tie material in the ties of the
present invention. Typically, the flattened tube 2 has
dimensions of 200 x 200 mm. The tube 2 is folded, for
example in an automatic folding machine, about a series of
longitudinal fold lines to form a folded tube 4 which is
shown in Figure 2. The folded tube 4 is shown exaggerated in
thickness but it will be seen that it consists of a plurality
of folds whereby the transverse width of the folded tube 4 is
considerably less than the transverse width of the original
flattened tube 2.
Referring to Figures 3 and 4, there is shown a method
of producing ties in accordance with the present invention.
In accordance with the method, a support web 6 comprises a
self-adhesive paper web 8 coated on its rear surface with a
pressure-sensitive adhesive and carried on a backing 10 of
release material. The support web 6 is fed out from a reel
12 thereof and fed under an adhesive applicator 14 which, as
is shown in Figure 3(a), applies a succession of layers 16 of
adhesive, such as water-soluble or hot melt adhesive,
transversely across the support web 6. In Figure 4 the
location of the assembly in Figure 3(a) is indicated. The
combined assembly then passes to a tie material applying
station 18 at which a succession of the folded tubes 4 of tie
material axe applied each to a respective layer 16 of
adhesive. Each folded tube 4 of tie material extends
transversely across the su~por~t web 6 and overlies the layer
16 of adhesive. The resultant assembly is shown in Figure
3(b) and the location of such assembly is shown in Figure 4.
The combined assembly then passes to a laminar material
applying station 20 at which a laminar material 22 is fed out
from a reel 24 thereof and urged by a roller 26 against the
upper surface of the combined assembly of the folded tubes 4
on the support web 6. The laminar material 22 comprises a
self-adhesive plastics material, such as polypropylene, which
is coated on one surface with a pressure-sensitive adhesive.
The laminar material 22 is adhered over the folded tubes 4
and the support web 6 by its self-adhesive surface. The
combined assembly then passes to a die-cutting station 28 at
which the combined assembly is passed between an upper
die-cutting roller 30 and a.lower backing roller 32. At the
die-cutting station 28 the composite web is slit
longitudinally with one or more longitudinal slits 34, as
shown in Figure 3(c), thereby to cut each folded tube 4 into
a plurality of folded lengths 36 of tie material, each of
which is disposed on a respective support piece 38 which has
been cut from the support web 6 and each of which is covered
by a laminar material piece 40 which has been cut from the
laminar material 22. The opposed ends of the folded tube 4
are cut away and are removed together with the waste of the
support web 6 and the laminar material 22. The resultant
assembly is shown in Figure 3(c) wherein a plurality of ties
in accordance with the present invention are disposed on
respective slit lengths 42 of release material 10 and are
longitudinally oriented with respect to each other. The
resultant plurality of lengths 42 of release material 10
carrying the respective successions of ties are wound up onto
respective reels 44.
The resultant tie 46 for a bag in accordance with the
present invention is shown in Figure 5. It will be seen that
the resultant tie 46 comprises the self-adhesive support
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piece 38 which is carried on the strip 42 of release material
and has adhered thereto in succession the folded length 36 of
tie material and the laminar material portion 40. It will be
seen that the laminar material portion 40 extends past both
ends of the folded length 36 of tie material and the two free
ends of the laminar material portion 40 are adhered by the
self-adhesive surface thereof and/or the adhesive layer 16 to
the support piece 38. The folded length 36 of tie material
is securely retained between the laminar material portion 40
and the support piece 38.
When it is desired to apply the ties to bags, the
strip 42 of release material is pulled away from the support
piece 38 and the support piece 38 is adhered by its
self-adhesive surface to a bag. This can be done either
manually or at high speed using a high speed labelling
apparatus. When it is desired to utilise the tie, the
laminar material portion 40 is pulled away from the support
piece 38 and this releases the folded length 36 of tie
material. Alternatively, the folded length 36 of tie
material may simply be pulled out from between the laminar
material portion 40 and the support piece 38. The folded
length 36 of 'tie material can then be unfolded to form a loop
and thus can be used, if desired by forming a slip knot, to
tie the neck of the bag.
In alternative embodiments, the folded length of tie
material does not require to be a loop but can be a simple
length which is free at both ends.
A second embodiment of a tie 50 for a bag in
accordance with the invention is shown in Figure 6. In this
e~odiment, the tie consists simply of a folded length 52 of
tie material, this being of the same construction and same
material as the folded length shown in Figure 5 relating to
the first embodiment. In contrast to the first embodiment,
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no laminar material portion overlies the folded length 52.
The folded length 52 is retained in its folded condition by
the adhesion of the rear surface of the folded length 52
directly to a backing 54 of release material by means of a
layer 56 of pressure-sensitive adhesive. The rear surface of
the folded length 52 comprises the rear surface of a rearmost
body portion 58 over which a succession of folded lengths are
disposed and the rear surface of an overlapping flap 60 which
is disposed adjacent the rearmost portion 58 and retains the
folded length 52 in its folded condition. Thus it will be
seen that the second embodiment also does not require a
support piece to which the folded length is adhered but
rather the folded length is coated on its rear surface with a
pressure-sensitive adhesive and is adhered directly to a
release material.
The bag tie 50 of the second embodiment may be made
by substantially the same method which is described with
reference to Figure 3 and 4. The method is modified in that
the support web simply comprises the backing 54 of release
material and the self-adhesive paper support web is omitted
whereby the folded tubes 4 are applied directly to the
backing 54 of release material to which adhesive layers have
already been applied. In addition, laminar material is not
applied over the assembly of folded tubes on the web. The
folded tubes are simply die-cut as shown in Figures 3 and 4.
When it is desired to apply the bag tie 50 to a
plastic bag, the bag tie 50 is removed from the backing 54 of
release material and this strips off from the backing 54 the
layer 56 of pressure-sensitive adhesive together with the bag
tie 50 and the bag tie 50 can be adhered to a plastics bag by
the layer 56 of pressure-sensitive adhesive. The bag tie is
applied near to the mouth of the bag. When it is desired to
tie up the bag by use of the bag tie 50, either the bag tie
50 can be separated from the bag by separation of the tie
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and the bag at the adhesive interface or alternatively the
folded portions of the bag tie can be pulled out from between
the rear most portion 58 and the top most portion 62 and used
to tie the bag.
The embodiment of Figure 6 may be modified by
providing a laminar material portion over the folded length.
The laminar material portion has the same construction and i~
manufactured in the same manner as that of the embodiment of
Figures 1 to 5.
A further embodiment of a bag tie in accordance with
the present invention is illustrated with reference 'to
Figures 7 and 8. Figure 7 shows the bag tie 64 adhered to a
plastics bag 66 in the region of the mouth 68 thereof. The
bag tie 64 has a similar construction to that shown in Figure
6 but is modified in that instead of the folded length 70
being adhered directly to a backing of release material by a
layer of pressure-sensitive adhesive the folded length 70 is
adhered by a layer of adhesive to a support piece 72 which is
coated on its rear surface with a pressure-sensitve
adhesive. The support piece 72 has a construction which is
similar to that shown in Figure 5. As will be clear to the
man skilled in the art, the bag tie 64 of the third
embodiment can be made by employing the method illustrated in
Figures 3 and 4 but with the omission of the laminar
material. The bag tie 64 of the third embodiment has a
construction similar to that of the first embodiment shown in
Figure 5 but with the omission of the laminar material
portion.
As is clear from Figure 7, the bag tie is adhered by
the pressure-sensitive adhesive surface of the support piece
72 to the plastics bag in the region of the mouth 68
thereof. When it is desired to close the bag, the folded
length 70 is unfolded and than tied to form a slip knot 74
which is tightened so as to close the neck 76 of the bag 68.
The support piece 72 can remain adhered by its self-adhesive
surface to the bag 66.
