Note: Descriptions are shown in the official language in which they were submitted.
20~5~
PATENT
DOCKET NO. 46818CAN8A
ADHESIVE TAPE CLOS~RE
TECHNICAL FIELD
The invention related to an adhesive tape closure for
sealing containers.
BACKGROUND ART
Adhesive tapes for sealing containers which comprise a
backing in tape form and an adhesive layer on one side
thereof have been known.
Normally, adheæive tapes of this kind are affixed over
the joint which is formed when the movable panels or flaps
cf a container~such as a carton are moved down to close it.
When a container so closed is to be opened, the previously
affixed adhesive tape has to be cut by means of a suitable
instrument such as a razor blade, a knife or a pair of
scissors along the joint between the carton's panels. This
procedure is disadvantageous in that an instrument is
required for opening the carton and in that the adhesive
tape having been cut apart remains on the carton after the
latter has been opened, rendering it unserviceable for re-
use.
For these reasons, attempts have been made to develop
adhesive tapes for sealing and opening cartons which are
adapted to be stripped completely from the carton being
opened. To this end, the two ends of the adhesive tape
used for sealing the carton are rendered non-adhesive by
being folded over on themselves for a limited length so
that free tabs are formed at the ends of the affixed tape
which a worker may grasp by his/her fingers so as to
withdraw the adhesive tape as the carton is being opened.
Adhesive tapes of this kind are described in DE-OS 20 11
2~55~02
360, British Patent Application 21203,720, PCT W0
88/03897, U.S. Patent 4,227,995 and EP-A 0 250 353.
A shortcoming of these prior adhesive tapes is that
the free stripping tabs inhibit the shifting and stacking
of closed cartons placed side by side or on top of each
other. In addition, they may be damaged during shipment 80
that the carton has to be opened later on, as in the past,
by means of a suitable cutting instrument.
U.S. Patent 4,647,485 discloses an adhesive tape which
has parallel score lines or perforations extending in
parallel with the center line and terminating at stripping
tabs at both ends of the adhesive tape. In the process of
opening a carton closed by means of an adhesive tape of
this kind, the danger of the stripping tab being ripped
away is reduced, and the narrow strip of adhesive tape
between the two score lines is easily removed for opening
the carton.
A shortcoming of the adhesive tapes disclosed in the
'485 patent is that their durability is limited since a
considerable potential exists of the carton opsning
unintentionally along the score lines or perforations while
the closed carton is handled and transported.
It is known from US Patent 4 741 935 to provide an
adhesive tape closure having first and second lower tape
strips each including an adhesive coating. The first and
second lower tape strips are partially overlapping along
adjacent edges. An upper tape strip is releasably adhered
to the first and second lower tape strips and is at least
coextensive with the overlapped portions of the lower tape
strips. Each of the lower tape strips is adhesively
secured to one of two adjacent container parts with the
overlapped portion generally positioned at the juncture of
the container parts.
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To disconnect the container parts the upper tape strip
is delaminated by grasping a tab projecting from an edge of
the upper tape strip. The overlapped portion precludes
delamination of the lower tape strips from the container
parts as the upper tape strip is removed. The lower tape
strip6 are then manually separated from each other at the
overlapped portion to disconnect the container parts.
Further, all prior adhesive tape closures are
disadvantageous in that they are suited solely for sealing
a single carton so that, even if adapted to be removed
completely after the carton has been opened, the carton
once used cannot be used anew because of the other
inscriptions applied thereto (consignor, consignee, etc.)
and has to be discarded. In the light of the great number
of containers - particularly cartons - used for packaging a
wide variety of products, this shortcoming aggravates the
problem of an environmentally acceptable disposal of
packaging materials.
On this basis, the object underlying the invention is
to provide an adhesive tape closure which not only is
suited for reliably sealing and packaging containers, but
as6umes additional functions and, in particular,
facilitates the process of opening the container.
~ISCLOSURE OF INVENTION
In accordance with the invention, the adhesive tape
closure has no adhesive in intermittent limited portions
thereof so that adhesive sections of the adhesive coating
on the backing are joined by non-adhesive sections on both
sides thereof.
According to a preferred embodiment of the invention,
nonadhesive sections are either free of adhesive, the
surface of a pressure-sensitive adhesive coating is
inactivated (e.g. rendered non-adhesive) in said
non-adhesive sections, or an activatable (e.g. heat
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activated) adhesive is not activated in the said
non-adhesive sections.
According to another preferred embodiment, the
5 adhesive effect of the adhesive coating sections is
inactivated or destroyed in the total area or in de~ired
portions of said limited sections by a cover sheet of paper
or a plastic material, a print of non-adhesive lacquer, a
polychrome print, or a neutralizing ink.
According to another preferred embodiment, the
adhesive coating has been inactivated by a print of an
adhesion-destroying coating.
According to another preferred embodiment, the backing
i8 paper, a plastics material or a combination thereof.
According to another preferred embodiment, the backing
is light transmissive (i.e., translucent or transparent).
According to another preferred embodiment, the backing
is polyester, bi- or monoaxially oriented or nonoriented
polypropylene, PVC, polyethylene-coated paper or
polyethylene.
According to another preferred embodiment, the cover
sheet has on the side facing the adhesive a low adhesion
backsizing coating.
According to another preferred embodiment, the cover
sheet sectionally inactivating said adhesive coating has
the same width as adhesive tape a smaller width than
adhesive tape or a greater width than adhesive tape.
According to another preferred embodiment, the cover
sheet is visible through transparent backing and i8
circular, square or rectangular in shape.
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According to another preferred embodiment, the cover
sheet and the backing thereon are perforated or partly
incised on one side in a direction transverse to the
longitudinal direction of the adhesive tape.
According to another preferred embodiment, the cover
sheet is narrower along one side than the subjacent backing
to cause a pocket to be formed which has an opening
transverse of the longitudinal direction of the tape for
the introduction of a sheet bearing infcrmation in between
the adhesive tape and the substrate to which it is adhered.
According to another preferred embodiment, the cover
sheet is narrower than backing thereon along both sides and
in that said backing has therein a slot extending over the
width of cover sheet to cause a pocket to be formed which
has an opening in the longitudinal direction of the tape
for introducing information in between the adhesive tape
and the substrate to which it is adhered.
According to another preferred embodiment, the cover
sheet i8 provided with an indicia imprint.
Below some of the preferred embodiments presented
above are explained further.
The backing used for making the adhesive tape
preferably i8 light transmissive (i.e., translucent or
transparent). It may be paper or a light transmissive
(i.e., translucent or transparent) plastics material. The
coat of an adhesive material applied to the substrate
preferably is self-adhesive or pressure-sensitive.
The adhesive coating may be sectionally inactivated,
i.e., rendered non-adhesive, by coating it with printing
ink or by placing a sheet of paper, a polymer film, a
prefabricated label or an address label in a desired size
thereon. Preferably, the inactivating sheet placed
sectionally on the adhesive coating has the same width as
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the adhesive tape, but may be narrower or broader than the
adhesive tape.
The covering sheet, which is visible through the ligh~
transmissive (i.e., translucent or transparent) backinq,
preferably i6 printed on its side facing the adhesive
coating; also, it may be any desired shape such as
circular, square or rectangular in shape.
The print on the sheet which is to be visible through
the light transmissive (i.e., translucent or transparent)
backing of the adhesive tape may be a promotional text or
any kind of information as may relate to the manufacturer,
the contents of the container, the consignor, the
lS consignee's address, etc.
As a consequence, all information previously applied
to the container's or carton's outer surface at locations
outside the adhesive tapes can now be omitted so that,
after the inventive adhesive tape has been removed, the
resultant container is totally neutral and suited for reuse
or easy recycling without tape residues. This enables
considerable savings to be realized in terms of carton raw
materials; in addition, the cost of producing containers,
and particularly cartons, will be greatly reduced.
Further, since the containers or cartons are reusable, a
substantial burden is lifted from the environment, and the
problems raised by an environmentally acceptable disposal
of such containers or cartons cease to exist.
For opening a container sealed with the inventiYe
adhesive tape closure, it is sufficient to apply to the
bottom surface of the adhesive tape a non-adhesive section
such as a sheet which renders the adhesive tape in that
area non-adhesive so that it may be lifted easily from the
container it seals, and to sever it at right angles to the
extent of the adhesive tape by means of a suitable
instrument (razor blade, knife or scissors). Since the
adhesive tape previously applied to the carton is
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internally stressed, the two sections of the covering
sheet, now stress-relieved, will move slightly upwards so
that they form stripping tabs a worker can easily manually
grasp to completely strip the adhesive from the container.
According to a preferred embodiment of the invention,
it is possible to provide both the covering sheet and the
transparent backing with perforations or partial incisions
at right angles to the length of the tape so that the
container may be opened without an instrument simply by
severing the tape at the perforations or a partly incised
position and then completely stripping the adhesive tape
away.
The cover sheet sectionally inactivating the adhesive
coating of the inventive adhesive tape may be provided on
its side facing the adhesive coating with any indicia,
which will be visible to an observer through the
transparent backing. The overlying backing - preferably a
polymer film such as biaxially oriented polypropylene -
protects the information against external damage and
moisture 80 that the consignor or consignee, for example,
will be easily legible at any time even if the container
sealed by means of the inventive adhesive tape is exposed
during transport to moisture (e.g. rain) or substantial
mechanical strain (e.g. by stacked cartons shifting
relative to each other).
Further, the cover sheet may be provided with
promotional information in attractive colors so that the
container sealed by means of the inventive adhesive tape
closure constitutes an attractive advertising media.
Since non-adhesive sections may be placed at suitable
distances along the inventive adhesive tape closure by
affixing cover sheets to it in desired positions, yet only
one such sheet must be cut apart or torn open for opening
the container, the information on the remaining sections or
cover sheets may be retrieved undamaged - e.g. a label
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showing the address of the consignor or the consignee; the
label may easily be stripped from the backing since the
side of the cover sheet facing the adhesive coating is
preferably provided with an adhesive-repellent surface.
Moreover, the inventive adhesive tape closure
constitutes an effective closure of the container or carton
it is used to seal since it can be detected at any time
whether the has been opened or not before it arrives at its
destination. Should the container have been opened
inadvertently or tampered with before its arrival, this
condition may be recognized by the fact that the cover
sheet of paper is cut or torn apart even if the carton has
been resealed by sticking a length of adhesive tape across
the cut.
According to another preferred embodiment of the
invention, at least one cover sheet affixed to the
underside of the adhesive tape may be somewhat narrower on
one side that the superjacent backing of the adhesive tape
so that the adhesive tape is affixed continuously along one
edge thereof to the carton it is used to seal. This causes
a pocket to be formed which has an opening perpendicular to
the extent of the adhesive tape and with a depth somewhat
smaller than the width of the adhesive tape and a width
corresponding to that of the cover sheet. This opening may
be used to introduce into the pocket printed information
such as operating instructions, shipping papers,
advertising material or the like, which that receiver will
be able to retrieve from the pocket easily and in an
undamaged condition.
It is equally possible to create a pocket extending in
the longitudinal direction of the adhesive tape by using a
cover sheet which is narrower on both sides than the
superjacent backing of the adhesive tape so that the latter
is affixed in place on the container continuously along
both edges. By providing a slot a few millimeters wide in
a direction transverse to the longitudinal direction of the
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tape (preferably by punching it into the tape) and having a
length which may correspond to the width of the cover sheet
thereunder, a pocket is formed in the longitudinal
direction of the tape between the cover sheet and the
surface of the container thereunder, such pocket also being
suited to receive printed information such as operating
instructions, shipping papers, advertising material and the
like. The inventive adhesive tape closure may be
manufactured by using conventional means. The cover sheet
to be applied intermittently to the underside of the
adhesive tape may be produced separately and provided with
any desired indicia. Suitable apparatus may be used to
apply it in the desired position on the adhesive tape
durinq the fabrication thereof to be coiled in roll form
together therewith and offered for sale in this form. The
on the cover sheets may be designed as desired by the final
user.
~RIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the invention will now be
explained in greater detail under reference to the attached
drawings.
Fig. 1 shows a carton to which the adhesive tape
closure of the present invention has been applied;
Figs. 2, 3 and 4 sequentially show the removal of an
adhesive tape closure of the present invention;
Fig. 5 shows an embodiment of the adhesive tape
closure of the present invention including indicia;
Fig. 6 shows an embodiment of the adhesive tape
closure of the present invention including a pocket for
receipt of a sheet member;
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Figs. 7 and 8 show alternative embodiments of pockets
formed in the adhesive tape closure of the present
invention; and
Figs. 9, 10 and 11 show additional alternate of the
adhesive tape closure of the present invention.
DETAI~ED DESCRIPTION
Fig. 1 shows a container, such as a regular slotted
carton (RSC) sealed with an adhesive tape closure 1
according to the present invention comprising a light
transmissive (i.e., translucent or transparent) backing 2
and a layer of a pressure sensitive adhesive applied to the
I5 underside of the backing and provided sectionally with
cover sheets 3 which render the respective covered or
inactivated portions of the adhesive coating non-tacky.
The cover sheets 3 are joined at both ends by adhesive
portions 4 of the pressure sensitive adhesive coating. The
non-tackified sections 3 of the adhesive tape may
preferably be totally free of adhesive; alternatively, the
surface of the adhesive layer may be inactivated such as by
a coating applied to the adhesive or a non-pressure
aensitive adhesive ~i.e., heat activated) may be nonactive.
Thus, adhesive tape closure 1, which is provided in
roll form, has alternating adhesive and non-adhesive sec-
tions. It is covered with a release coating on its reverse
; side.
Figs. 2, 3 and 4 show uses of the inventive adhesive
tape closure, which may be torn apart or cut apart by means
of a suitable cutting instrument (Fig. 3) along the line of
perforations 9 transverse to the longitudinal direction of
the tape. The free portions so formed of the cover sheet
serve as tabs for stripping the adhesive tape away (Fig.
4).
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Fig. 5 shows a length of the inventive adhesive tape
closure wherein indicia on cover sheet 3 i8 visible through
backing 2.
Fig. 6 shows another preferred embodiment of the
inventive adhesive tape closure in which cover sheet 3 is
narrower along one longitudinal side than adhesive tape
thereby forming a pocket 5 closed on three sides and having
an opening 6 at right angles to the longitudinal direction
of the adhesive tape for the introduction of information
sheets or the like between the cover sheet and the
sub;acent carton surface.
Figs. 7 and 8 show another preferred further
development of the inventive adhesive tape closure in which
cover sheet 3 is narrower along both longitudinal sides
than adhesive tape 1 and a slot 7 longer than cover sheet 3
is wide is formed transverse of the longitudinal direction
of the adhesive tape in backing 2 thereof to form a pocket
8 which i8 closed along three sides and open in the
longitudinal direction of the tape at slot 7 for receiving
information sheets between the cover sheet and the
subjacent carton surface. The information material
introduced through slot 7 may have indicia printed on its
portion protruding from slot 7 to display the nature of the
information therein.
Figs. 9 and 10 show another preferred development of
the inventive adhesive tape closure. In this case, cover
sheet 3a is circular and should have a diameter at least
equal to the width of the adhesive tape so that the
stripping tab is accessible and may be actuated.
Fig. 11 shows another preferred development of the
inventive adhesive tape closure used for sealing circular
containers having ends such as cans or the like.
Can-shaped containers of this kind frequently are sealed by
means of a length of adhesive tape which require the
provision of a stripping tab - an objective difficult to
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achieve. In this embodiment of the inventive adhesive tape
closure a cover sheet 3, e.g. of paper or flexible plastic,
is provided sectionally along adhesive tape 1 so as to
establish several positions along the periphery of the
can-shaped container where a tape stripping tab i8
available. Approximately centrally disposed along the
cover sheet 3 there is provided transversely of the
longitudinal direction of the adhesive tape a line of
perforations or an incision 10, the latter on one or two
sides of the adhesive tape in the area of the non-adhesive
section such as cover sheet 3. Thus, it is possible to
raise the prepared stripping tab in these positions and to
strip the adhesive tape, if needed. The adhesive tape
closure of the present invention offers the following
advantages over the state of the art:
1) It enables a mechanically easy and complete
removal of the tape from the container it seals -
particularly a carton - so that the container or
carton may be recycled and/or reused.
2) It has an attractive appearance and enables
easily visible information to be applied to the
container. for identifying and distinguishing its
contents; the attractive appearance of the
inventive tape closure distinguishes it
advantageously from prior printed adhesive tape
closures.
3) A container - particularly a carton - sealed by
the inventive adhesive tape closure has no
exposed stripping tabs on the surface thereof
which might be damaged during handling or
transport or interfere with the shifting or
stacking of the containers, particularly cartons.
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4) The inventive adhesive tape closure
constitutes a valuable and attractive
advertising media which may be used by
both the consignor and the consignee.
5) The inventive adhesive tape closure is superior
to prior printed adhesive tapes in that it may be
produced economically on existing eguipment
without requiring a costly additional printing
treatment. The cover sheets bearing the indicia
may be produced separately and applied to the
adhesive coating of the adhesive tape closure by
mechanical means or by hand without expensive
retrofitting or additional investments being
needed.
6) The process of making conventional tapes does
not have to be converted so that no additional
investments accrue.
7) Finally, the inventive adhesive tape closure
makes it possible to recognize immediately
whether the container is seals - particularly a
carton - has been opened intentionally or
inadvertently and resealed before reaching the
consignee: the served or torn paper of the cover
sheet is easily detected and cannot be restored
to its former condition.
The following -examples explain further the structure of
adhesive tape closure according to the present invention.
Exam~le 1
The backing (2) is a 50 mm wide biaxially oriented
polypropylene film having a thickness of 28 microns, which
is coated with a pressure sensitive adhesive at 18 grams
per square meter. The adhesive is composed of
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46% per weight o~ natural rubber,
41.5% per weight of a hydrocarbon resin,
0.3% per weight antioxidant ~Phenolic type)
12.2% per weight Tio2
The cover sheet (3) is a paper mask 50 mm long and 50 mm
wide. Backing (2) and cover ~heet (3) are perforated.
Fig. 2 shows the actual design of the adhesive tape closure
of this Example. The release coating of the adhesive tape
is polyvinyloctadecylcarbammate.
Example 2
The backing (2) is a 50 mm wide non-plasticized-
polyvinyl-chloride (UPVC) film having a thickness of 34
micron6 which is coated with a pressure sensitive adhesive
at 20 grams per square meter. The adhesive is composed of:
52.1% per weight natural rubber
47.6% per weight of a hydrocarbon resin
0.3% per weight antioxidant (Phenolic type).
The cover sheet (3) is a paper mask 80 mm long and 60
mm wide, and is on one side 10 mm broader than the backing
(2).
The release coating of the adhesive tape is
polyvinyloctadecylcarbammate.
ExamDle 3
The backing (2) is a 80 mm wide polyester film having
a thickness of 50 microns which is coated with a pressure
sensitive adhesive at 32 grams per square meter. The
adhesive is composed of:
49.5% by weight synthetic rubber
49.5% by weight hydrocarbon resin
1.0% by weight antioxidant (Phenolic type)
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The cover sheet ~3) is a circular paper mask having a
diameter of 80 mm. Backing (2) and cover sheet ~3) are
perforated. The cover sheet is provided with indicia, as
shown in Fig. 10.
The release coating of the adhesive tape is an
urethane low adhesion backsize.
The invention has been explained above under reference
to specific preferred embodiments; however, it will be
obvious to the person skilled in the art that it is not
limited to them. Rather, it may be altered and modified in
various ways without leaving the scope of the pre3ent
invention.
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