METHOD FOR APPLYING A REMOVABLE PRINTED MARKING TO A CONTAINER

PROCEDE D'APPLICATION D'UNE MARQUE IMPRIMEE AMOVIBLE SUR UN CONTENEUR

English Abstract

For the application of a removable printing to a container, such as a plastic
crate, a layer of ink, which forms the printing and is
provided on one side with a bonding agent for bonding the layer of ink to the
container, is transferred to the container from a carrier film
to which the layer of ink has been applied to the side not provided with
bonding agent. The bonding agent has such properties that in
normal conditions of use of the container the layer of ink adheres firmly to
the container and in predetermined conditions which differ
from the conditions of use the bonding agent and the layer of ink are easy to
remove from the container. This produces a container with a
high-quality printing, which printing is easy to replace with another
printing.

French Abstract

Afin d'appliquer une impression amovible sur un conteneur tel qu'une caisse en plastic, la couche d'encre formant l'impression comporte sur l'un de ses côtés un agent de liaison qui va assurer son adhésion au conteneur. Cette couche est transférée sur le conteneur depuis un film de support sur lequel elle a été préalablement appliquée de son côté dépourvu d'agent de liaison. Cet agent de liaison possède des propriétés telles que, dans des conditions d'utilisation normales du conteneur, la couche d'encre va adhérer fermement audit conteneur. Dans des conditions prédéterminées autres que les conditions d'utilisation, l'agent de liaison et la couche d'encre peuvent être facilement séparés du conteneur. Ce système permet d'obtenir un conteneur possédant une impression d'une grande qualité qui peut être facilement remplacée par une autre impression.

Claims

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CLAIMS
1. Method for applying a removable printing to a container, in
which a layer of ink, which forms the printing, is transferred
from a carrier film, to which the layer of ink has been applied by
means of conventional printing techniques, to the, container, the
layer of ink being provided on the side contacting the container
with an adhesive for bonding the layer of ink to the container,
the adhesive having such properties that in normal conditions of
use of the container the layer of ink adheres firmly to the
container and in predetermined conditions of higher temperature,
greater than about 40°C, which differ from the normal conditions
of use, the adhesive and the layer of ink are easy to remove from
the container.
2. Method according to claim 1, in which the adhesive and the
layer of ink can be removed together from the container.
3. Method according to claim 1 or 2, in which the layer of ink
is provided with a layer of lacquer on the side not provided with
adhesive, the layer of lacquer being situated between the layer of
ink and the carrier film when the layer of ink has been applied to
the carrier film.
4. Method according to claim 3, in which the layer of lacquer
projects beyond contours of the layer of ink, and a part of the
layer of lacquer projecting beyond the layer of ink is provided
with an bonding agent for bonding the projecting part of the layer
of lacquer to the container.
5. Method according to claim 4, wherein the bonding agent is
the same as the adhesive on the layer of ink.
6. Method according to claim 5, in which the bonding between
the layer of ink or the layer of lacquer and the carrier film is
weaker than the bonding which the adhesive produces between the
layer of ink and any part of the layer of lacquer which may
project beyond the layer of ink and the container.

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7. Method according to any one of claims 1 to 6, in which the
bonding between the adhesive and the container substantially
disappears at a temperature which is higher than the temperature
at which containers are normally cleaned.
8. Method according to claim 7, in which the bonding between
the adhesive and the container disappears at a temperature of
approximately 60°C.
9. Method according to any one of claims 1 to 6, in which the
bonding between the adhesive and the container substantially
disappears under the influence of UV rays.
10. Method according to any one of claims 1 to 9, in which the
carrier film is a carrier film web to which several layers of ink
which form the printing have been applied.
11. Method according to any one of claims 1 to 10, in which the
layer of ink is transferred mechanically from the carrier film to
the container.
12. Method according to any one of claims 1 to 11, in which the
printing is applied to a container made of plastic material.
13. Method according to claim 12, wherein the plastic material
is a polyalkene.
14. Method according to claim 13, wherein the polyalkene is
polyethylene or polypropylene.
15. Method according to any one of claims 1 to 14, in which the
container is a plastic crate or box and the printing is applied to
an outside wall of the crate or the box.
16. Plastic container provided with a removable printing
comprising a layer of ink which forms the printing and which is
applied directly to the container by means of an adhesive, the
adhesive having such properties that in normal conditions of use
of the container the layer of ink adheres firmly to the container

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and in predetermined conditions of higher temperature, greater
than about 40°C, which differ from the normal conditions of use,
the adhesive and the layer of ink are easy to remove from the
container.
17. Plastic container according to claim 16, in which a layer of
lacquer is applied over the layer of ink and a region immediately
next to the layer of ink.
18. Plastic container according to claim 16 or 17, in which the
bonding between the adhesive and the container substantially
disappears at a temperature which is higher than the temperature
at which containers are usually cleaned.
19. Plastic container according to claim 18, in which the
bonding between the adhesive and the container disappears at a
temperature of approximately 60°C.
20. Plastic container according to claim 19, in which the
container is a crate or box, and the printing is applied to an
outside wall of the crate or box.
21. Plastic container according to claim 20, wherein the crate
or box is made of a polyalkene.
22. Plastic container according to claim 20, wherein the
polyalkene is polyethylene or polypropylene.
23. Film to which a layer of ink which forms a printing is
applied to one side by means of conventional printing techniques,
which layer of ink on the side facing away from the film is
provided with an adhesive for bonding the layer of ink to a
substrate, the adhesive having such properties that in normal
conditions of use of the substrate the layer of ink adheres firmly
to the substrate and in predetermined conditions of higher
temperature, greater than about 40°C, which differ from the normal
conditions of use, the adhesive and the layer of ink are easy to
remove from the substrate.

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24. Film according to claim 23, in which a layer of lacquer
connected to the layer of ink is present between the layer of ink
and the film.
25. Film according to claim 23 or 24, in which the film is in
the form of a film web to which several layers of ink which form
the printing have been applied.
26. Film according to claim 25, in which on the side not
provided with a layer of ink the film is provided with an anti-
bonding layer.
27. Film according to claim 26, wherein the anti-bonding layer
is a silicone layer.

Description

CA 02247110 2002-05-31
~ETHfl~ FOR APPLYING A REMOUABt~ FRINTE~ BARKING TO A CONTAINER
The invention relates to a method for applying a
removable printing to a container.
Applying a printing to a container, for example a
bottle crate, is generally known. The printing can be
applied to the container by flexographic printing or screen
printing techniques. However, such a printing is of a
permanent character and cannot be removed from the con~
tamer, or can be removed only by very special measures.
In practice, there is a need for applying a differ-
l0 ent printing to a certain type of container {far example,
if a different product is to be packed therein, or in the
case of advertising promotions). For this purpose, the
printing on the container must be relatively easy to remove
from it without the container being damaged. On the other
hand, the printing must be durable and of good optical
quality, in order to ensure that a container can be used
for a specific brand of product for quite a long period of
time.
Labels which can be affixed to containers and
removed from them again are known. Such labels contain a
paper, aluminium or plastic film which is provided with a
special layer of bonding agent. However, a container
provided with such a label does not have a perfect
appearance. Moreover, the thickness of such labels invites
undesirable removal. During the industrial removal of
labels from a large number of containers a relatively large
quantity of material comes off and requires further
processing.
The invention provides a method which makesit
3o possible to apply an optically pleasing printing to a
container, which printing is difficult for the user to
remove from the container, but is easy to remove from the
container industrially, the container being clean again
after the printing has been removed, so that a new printing
can be applied.

CA 02247110 2002-05-31
This is achieved according to the invention
by a method,for applying a removable printing to a
container, in which a layer of ink, which forms the
printing and is provided on one side with a bonding agent
for bonding the layer of ink to the container, is trans-
ferred to the container from a carrier film to which the
layer of ink has been applied at the side not provided with
bonding agent, the bonding agent having such properties
that in normal conditions of use of the container the layer
2.0 of ink adheres firmly to the container and in predetermined
conditions which differ from the conditions of use the
bonding agent and the layer of ink are easy to remove from
the container.
Use of the method according to the invention
produces a container with a high-quality printing which is
relatively easy to replace by another printing.
The invention also relates to a plastic container
provided with a removable printing comprising a layer of
ink which forms the printing, which layer of ink is applied
to the container by means of a bonding agent, the bonding
agent having such properties that in normal conditions of
use of the container the printing adheres firmly to the
container and in predetermined conditions which differ from
the conditions of use the bonding agent and the layer of
ink are easy to remove from the container.
The invention also relates to a film to which a
layer of ink which forms the printing is applied to one
side, which layer of ink on the side facing away from the
film is provided with a bonding agent for bonding the layer
of ink to a substrate.
Preferred embodiments of the method, the plastic
container and the film according to the invention are
def fined in the following.
The invention will be explained in greater detail
with reference. to the exemplary embodiment below.
The exemplary embodiment relates to the application
of a removable printing to a plastic bottle crate which is
preferably made of a polyalkene, such as polyethylene or
polypropylene, and in which the printing is applied to the

CA 02247110 1998-08-27
WO 97/32293 PCT/NL97/00093
- 3 -
outside wall of the crate. However, the method according to
the invention can also be used for other types of
containers, such as plastic boxes and glass or plastic
bottles.
When the method according to the invention is
applied to a clean crate, a layer of ink, which forms the
printing and is provided on one side with a bonding agent
for bonding the layer of ink to the crate, is transferred
from a carrier film to the crate. The layer of ink is
applied to a carrier film at the side not provided with a
bonding agent. The carrier film is preferably a calendered
PET, polypropylene or polyethylene film with a thickness
of
40 - 50 ~Cm.
If the printing is being applied on an industrial
scale, the printing will generally come from a carrier film
web to which several layers of ink which form the printing
have been applied. If the carrier film web has been placed
on a roll, the side not provided with the printing will
preferably be provided with an anti-bonding layer, for
example a silicone layer. The printing will preferably be
applied mechanically to the crates.
In order to be able to guarantee a perfect
appearance and good protection of the printing, the layer
of ink can be provided with a layer of lacquer on the side
not provided with a bonding agent. Consequently, when the
layer of ink has been applied to the carrier film, the
layer of lacquer will be situated between the layer of ink
and the carrier film. In order to guarantee optimum protec-
tion of the printing on a crate, the layer of lacquer
3o projects beyond the contours of the layer of ink and is
likewise provided with a bonding agent in that region,
preferably the same bonding agent as that also applied to
the layer of ink. Once the printing has been applied to the
' crate, the layer of ink is completely enclosed between the
wall of the crate and the layer of lacquer.
In order to be able to remove the printing from the
crate again relatively easily, the bonding agent has such
properties that in normal conditions of use of the crate
the layer of ink and the layer of lacquer adhere firmly to

CA 02247110 1998-08-27
WO 97/32293 PCT/N~.97/00093
- 4 -
the crate and in predetermined conditions which differ from
the conditions of use the bonding agent, the layer of ink
and the layer of lacquer are easy to remove from the crate.
An example is a bonding agent which loses its adhesion to
the crate at a temperature which is higher than the
temperature at which crates are usually cleaned. Crates are
generally cleaned with water at a temperature of approxi-
mately 40°C. By using a bonding agent which becomes
ineffective at a temperature of approximately 60°C and
to higher, it is possible to allow crates from which the
printing is to be removed to soak for some time in water at
60°C and higher (to which an agent for reducing the surface
tension has been added if necessary) and then to remove the
printing using a high-pressure water jet (for example 15
bar) .
In order to accelerate the soaking process, a
slightly porous layer of ink and layer of lacquer, if
present, can be used, so that water can penetrate rapidly
to the bonding agent.
It is also possible to use a bonding agent which
becomes ineffective under the influence of W rays. In that
case also, the printing can be removed using a high-
pressure water jet.
The printing can be applied to the carrier film by
means of conventional printing techniques, such as
flexographic printing or screen printing techniques. This
also applies to the layer of lacquer. In practice, a layer
of lacquer will first be applied to the carrier film, with
such dimensions that said layer of lacquer projects
3o slightly beyond the layer of ink to be applied
subsequently. The layer of ink will then be applied to the
layer of lacquer and, finally, a bonding agent will be
applied to the layer of ink and the part of the layer of
lacquer projecting beyond the layer of ink, likewise using
printing techniques.
The bonding between the layer of ink or layer of
lacquer and the carrier film must, of course, be weaker
than the bonding which the bonding agent produces between
the layer of ink and layer of lacquer and the crate. This

CA 02247110 2002-05-31
means that the layer of ink is easy to transfer from the
carrier film to the crate without the layer of ink or the
layer of lacquer being damaged. The bonding between the
layer of ink or the layer of lacquer arid the carrier film
is the result of adhesion between the layer of ink or layer
of lacquer and the carrier film.
As already mentioned, the layer of ink will
generally be transferred mechanically from the carrier film
to the crate. Tt must be ensured in this case that the
l0 layer of ink is pressed down well on the substrate, and
that no air inclusions arise between the layer of ink and
the crate wall.
The result of the application of the method
according to the invention is a crate with a printing of
very high quality, but which can easily be removed again,
in such a way that after the removal of the printing the
surface of the crate is undamaged, and a new printing can
be applied to the crate.
Good results are obtained in practice with a
dispersion glue manufactured by KIWO, known by thetrade-mark
D 3206 VP, as the bonding agent. Of course, the invention
is not limited to this bonding agent.