Note: Descriptions are shown in the official language in which they were submitted.
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METHOD OF LABELING CONTAINERS
TO FACILITATE DE-LABELING
' Technical Field
The present invention relates to a method of
labeling containers with labels which are prepared to
facilitate being stripped from the containers.
BaCk~rOUnd Art
Containers for products are labeled by various
methods. One example of a container produced in high
volumes which has constantly been improved in its method
of labeling is a soft drink container. These containers
were originally formed of glass directly decorated with
painting or printing . Soft drink cans were subsequently
developed wherein labels were directly printed on the
l5 surface of the cans by lithography. Due to environmen-
tal and cost considerations, directly decorating con-
tainers such as glass bottles and cans has been sup-
planted by applying pre-printed labels to these contain-
ers. These labels can be produced and applied at low
cost to containers as part of a container filling line.
Originally, these labels consisted of paper and were
applied to the containers with glue. The paper labels
were subject to degradation from moisture and other
environmental factors.
The bottling industry improved paper labels by
applying a thin layer of plastic over the paper for
~ protection. Other labels developed include polystyrene
foam labels and, more recently, film labels. Selection
~ of labeling materials for various containers is influ
enced by factors such as cost, convenience of applica-
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tion and use, and ability to reuse and recycle the
containers.
One problem in recycling or reusing containers
relates to the de-labeling or the removal of labels.
For example, paper labels which are pasted or glued on
containers are frequently removed by immersing the
labeled container into a washer of hot caustic solution.
An example of a machine used to apply caustic solution
to a labelled container is disclosed in U.S. Patent No.
4,044,783 issued to Babunovic, et al. However, caustic
solution baths do not work well with plastic labels
because plastic is impervious to moisture. Furthermore,
the washer may become subject to label congestion as a
large number of containers are fed through the washer in
a relatively short time.
Tough, axially oriented film labels are also
difficult to remove from containers. If a durable film
label is applied to a glass or plastic bottle, it can be
difficult to remove the label without harming the
surface of the container. In particular, when an
oriented film is applied to a polyethylene tetraphthal-
ate (PET) bottle, the known processes for de-labeling
containers can scratch or cut the underlying container.
It has been proposed that PET containers could be reused
without remelting if they could be de-labeled and
adequately sanitized without injury to the bottle.
Known de-labeling methods include mechanical
de-labelers wherein fingers are used to scratch and tear ,
the label from the container as it moves down a de-
labeling line. For instance, U.S. Patent No. 4,122,734 ,
issued to Hurst, discloses a label stripping machine
utilizing a razor for cutting off the label from the
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container. Another approach to cutting the label is to
use air or water jet knives. As disclosed in U.S.
Patent No. 4,717,442 issued to Hopson, air jets are
directed between the label and the container in order to
rupture the label.
A difficulty with either mechanical stripping
fingers, razors, or jet knife de-labelers, is control-
ling the depth of the cut and the force used to remove
the label in order to avoid scratching or cutting the
container. If a PET container is scratched or cut, it
is unusable and must be remelted before being recycled.
Likewise, if a glass container is cut or scratched in
the course of de-labeling, the container can be ruined,
requiring it to be remelted and reformed into a new
bottle.
A pressure sensitive, price tag is shown in
U.S. Patent No. 4,787,158 issued to Vitol. The dis
closed label has a score line which is provided for the
purpose of spliting the label if a consumer tries to
remove the price tag.
The prior art has not addressed the need for
a bottle labeling method which facilitates automatic de-
labeling without harming the containers as proposed by
applicant below.
2 5 Summary Of The Invention
' It is an object of the present invention to
provide a method of labeling containers with a label
that lends itself to being removed from the containers
by automatic de-labeling equipment.
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It is another object of the present invention
to provide a method of labeling containers including the
step of forming a frangible region on the label which
facilitates de-labeling without unduly weakening the
durability of the label.
It is yet another object of the present
invention to provide a method of labeling containers
with a label that is adapted to break in a frangible
region causing it to flag thereby facilitating de
labeling.
According to the present invention a method of
labeling containers is provided which facilitates
automatic de-labeling of the containers after consumer
use. The method includes preparing a container for
L5 labeling and preparing a label for application to the
container. In the process of preparing the label, a
frangible, or breakable, region is formed on the label
which may, in some applications, extend across the label
generally from the top to the bottom of the label. The
label is then applied to the container. The labeled
container may then be distributed tQ consumers for use.
The containers are then collected from the consumers for
reuse or recycling. A mechanical force is applied to
the labeled container to break the label initially at
the frangible region prior to separating the label from
the container_
The present invention is applicable to a
variety of labeling methods including the method wherein
labels are fed from a roll which is cut off into label
segments. Roll fed label segments are generally applied
- to the container by tacking the leading end of the label
to the container and then wrapping the label around the
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container. The trailing end of the label is then secured to
the container or the leading end of the label. The method
is also applicable to labels that are supplied from a pre-
cut stack of labels and applied to the container in a
5 similar manner. The method is even applicable to sleeve-
applied labels wherein labels are formed into sleeves and
then slid over one end of a container. In each method, the
label is either perforated or scored prior to application to
a container from one edge to the other to form a
substantially full height frangible region which permits the
label to break from edge to edge. Upon the frangible region
breaking, the label flags or extends outward from the
container.
Thus, according to one aspect the invention
provides a method of labeling a container, said method
comprising the steps of: preparing the container for
labeling; preparing a label with an adherent portion and an
extensive non-adherent portion for application to said
container; forming a frangible region on said non-adherent
portion of said label which extends across said label
sufficiently frangible to facilitate de-labeling without
unduly weakening the durability of the label; and applying
said label to said container to form a labeled container.
According to another aspect the invention provides
a method of labeling a container, said method comprising the
steps of: preparing the container for labeling; preparing a
pre-formed sleeve label for application to said container;
forming a frangible region on said sleeve label sufficiently
frangible to facilitate de-labeling without unduly weakening
the durability of the label; and sliding said sleeve label
over one end of said container and shrinking said sleeve
label to said container, said frangible region extending
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5a
across said sleeve label in the direction that said label is
slid over said one end of said container.
The method of the present invention facilitates
de-labeling by means of de-labeling machines which include
fluid jet knives, mechanical moving fingers or counter-
rotating rollers. Regardless of the de-labeling method
used, the method of labeling containers of the present
invention improves the operation of the de-labeling machines
and their effectiveness at removing labels from containers
while minimizing or eliminating damage to the containers
inflicted from the de-labeling machine.
Other objects and advantages of the present
invention will become more apparent in view of the attached
drawings and in light of the following detailed description
of the invention.
Brief Description Of The Drawings
FIGURE 1 is a flow chart illustrating the steps of
the process of the present invention;
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FIGURE 2 is a perspective view of a roll-fed
labeling apparatus including a label cutter and a
perforator;
FIGURE 3 is~ a perspective view of a sleeve
label being applied to a container;
FIGURE 4 is a perspective view of a cut and
stack label magazine applying the label to the contain-
er;
FIGURE 5 is a perspective view of a label
cutter and a perforator for forming a frangible region
on a label;
FIGURE 6 is a perspective view of a fluid
knife used to de-label a container at the frangible
region on a label;
FIGURE 7 is a plan view of a de-labeling
system wherein mechanical fingers are used to break a
label at a frangible region and strip it from a contain-
er; and
FIGURE 8 is a plan view of a bottle de-label-
ing apparatus wherein counter-rotating rollers are used
to first break the label at a frangible region after
which a vacuum label separating device tears the flag-
ging label from the container.
3~est Modes For Carryin~ Oui The Invention
Referring now to the drawings, in Figure 1, ,
the general steps of the present invention are shown
diagrammatically with references to the other Figures as
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appropriate to illustrate the steps of the invention.
As shown in Figure 1, the invention can be used to de-
label containers labeled by roll-fed, sleeve-applied, or
cut and stack labeling methods. The present invention
is not intended for use with pressure-sensitive type
labels having adhesive adhering the entire label to the
container since the inclusion of a frangible zone on the
label would not appreciably improve automatic de-label-
ing operations.
Referring now to Figures 1 and 2, a roll-fed
labeler 10 is shown wherein a roll of labels 12 are pre-
printed with label indicia and provided to the roll-fed
labeler 10. A web 14 is advanced from the roll of
labels 12 to a conventional label cutter 16. A perfora-
for 18 is provided to form a perforated or frangible
region on the label. After the cutter 16 cuts individu-
al segments from the web 14, the label segments are
provided to a vacuum drum 20 and then applied directly
to unlabeled containers 22 which are fed into the roll-
fed labeler 10. The labels are coated on leading and
trailing edges with an adhesive or other suitable
solvent, paste or glue. The leading edge of the labels
are then tacked to the unlabeled containers 22. The
labels are then wrapped around the container with the
leading edge adhering to the container and the trailing
edge adhering to the leading edge to form a labeled
container 24. Of course, the trailing edge could adhere
directly on the container. As can be appreciated, the
present invention can also be used with spot or full-
wrap labels provided these labels have extensive non-
adherent portions which will flag out from the container
upon breaking the label at the frangible region or zone.
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Referring now to Figures 1 and 3, a sleeve
applied label can also be provided with the present
invention. A container 30 can be labeled with a sleeve
32 which includes a score line 34. Similarly to the
frangible region, the score line 34 facilitates the de-
labeling process.
Referring to Figure 4, another approach to
labeling that can be used with the present invention is
a cut and stack labeling machine. With a cut and stack
labeling machine, a magazine 38 is provided with a stack
of labels 40. The labels 40 have a frangible region 42
which is a score or perforated line. The frangible
region 42 is formed on the labels 40 prior to being
loaded into the magazine 38. Labels 40 are applied to
containers 44 in accordance with conventional cut and
stack labeling techniques.
Referring now to Figure 5, a method of forming
a frangible region on a label with a label cutter 48 is
spawn. The label cutter 48 includes a vacuum drum 50
for supporting the labels. A conventional cutter knife
. 52 is adapted to cut labels supported by the vacuum drum
50 as it passes the label cutter 48. A perforator 54 is
preferably disposed at a circumferentially spaced
location from the cutter knife 52 in order to form a
fairly long segment of label material having a frangible
region between the adherent leading and trailing edges.
Referring now to Figure 1, after the frangible
region is formed on the label, the label is applied to
the container. Either new or recycled containers can be
labeled with any one of the conventional labeling
r
methods described. In many instances, labels are
shrink-fitted to the container by applying heat. The
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heat causes a film or foam label to contract forming a
tight fit on the container.
After labeling, the containers are provided
" through distribution channels to consumers for consump-
Lion of the product. Upon consumption, consumers are
encouraged to return the containers with deposits or the
like for recycling.
The empty labeled containers are collected and
supplied to an automatic de-labeling machine. As can be
appreciated from the de-labeling methods shown in
Figures 6, 7, and 8, various means of applying a mechan-
ical force to break the label can be provided. In
Figure 6, labeled containers 58 having labels including
a frangible region 60 are provided to a de-labeler. The
de-labeler consists of a fluid nozzle 62 which is used
to strip the label from the labeled container 58. Fluid
nozzle 62 may direct air or liquid such as water, toward
the labeled container 58 with a force sufficient to
break or rupture the frangible region 60 but with less
force than would be required to split other portions of
the label. Breaking frangible region 60 creates a
flagging label end 64 which hangs loosely from the
container. The label is then easily removed by a label
separator. The function of the label separator will be
described below.
Another de-labeling approach is shown in
Figure 7. A labeled container 68 is fed by a conveyor
to stripping finger wheels 70 which rotate against the
labeled container 68 causing frangible region 72 to
split resulting in flagging label ends 74. Again, the
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force applied to split the frangible region is less than
the force required to split other portions of the label.
Referring now to Figure 8, labeled container
80 may be provided to counter rotating rollers 82.
Rollers 82 apply tension to the label by surface contact
causing the frangible region 84 to break first resulting
in flagging label ends 86. The flagging label ends 86
provide broad surface area upon which the vacuum label
separator 88 may act to pull and strip the label from
the container. After the label is separated from the
container as shown in Figure 1, the label material can
be removed and discarded or recycled. The de-labeled
container may then be cleaned for reuse and provided
again to the label application line to receive a fresh
label.
It should be appreciated that a simple and
effective method for labeling containers so that they
may easily be de-labeled by automatic de-labeling
equipment has been disclosed. Applicant has disclosed
several different embodiments of the invention to
illustrate the invention and to provide an enabling
disclosure. The preceding description should not be
read in a limiting sense. The present invention should
be construed in accordance with the broad scope and
spirit of the following claims.
