Note: Descriptions are shown in the official language in which they were submitted.
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Method and Flat Structure for Detachably Fixing an Object to a
Surface
This invention relates to a method for detachably fixing an object to
a surface in which the object is fixed by means of two flat materials coated
on one side with a pressure-sensitive adhesive, the flat materials being
provided on their other sides with corresponding connecting elements for
interlocking these other sides with one another and being made in
particular in the form of tapes. In general, the surface mentioned is a
vertical wall although it may also be a horizontal or sloping surface, such as
a ceiling or an inclined wall.
Prior Art
A corresponding system of tapes for practising this method is known
by the name of "tesa Klettband selbstklebend" (Beiersdorf AG). The fixing
system consists on the one hand of a so-called hook tape which is provided
on one side with a pressure-sensitive adhesive and on its other side with a
plurality of hooks of the type normally used for velcro fasteners. The other
tape of this fixing system is again coated on one side with a pressure-
sensitive adhesive, but on its other side carries a nonwoven in which the
hooks of the other tape are able to engage. In the known fixing method,
the hook tape and the fleece tape are placed with their velcro fastening
sides on top of one another and pressed together. Following the removal
of a protective paper from the adhesive side of the fleece tape, the
adhesive side of the fleece tape is applied to the object to be fixed and
pressed firmly thereon. After the protective paper on the adhesive side of
the hook tape has been peeled off, the hook tape is applied to the cleaned
surface and pressed firmly thereon. In this way, the object on the one hand
is fixed to the surface, but on the other hand can easily be removed
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therefrom by separating the two tapes from one another.
Unfortunately, the disadvantage of this known fixing system and
method is that, after the object fixed to the surface has been removed
therefrom, the hook tape adheres to the surface which is not only
unattractive, but also impractical because this part of the surface can no
longer be used for other purposes. If the hook tape is also to be removed
from the surface, a small part of one end of the hook tape first has to be
detached so that the hand of the user is able to grip the hook tape in order
then to peel it off the surface.
Accordingly, in order to find a contact point for the hand for the
purpose of detaching the hook tape from the surface, tools such as knives,
screwdrivers etc. are frequently used to save the finger nails of the user.
However, where standard tools such as these are used, the surface is often
damaged, for example by scratching. In addition, it is almost impossible to
avoid residues of adhesive remaining behind on the surface and having to
be laboriously removed.
In addition, adhesive strips and corresponding fixing methods are
known under the names of "tesa Power Strips" and "tesa Poster Strips" and
are available from Beiersdorf AG. The only significant differences between
these two products lie in the thickness of the pressure-sensitive adhesive
and in their geometric shape. The ca. 2 to 3 cm long and 2 cm wide strips
consist essentially of a highly elastic pressure-sensitive adhesive. One end
is covered on both sides with a protective film. Finally, the entire surface
area of both sides is covered in known manner with another protective
paper.
To use these strips, one strip is detached from its protective paper
and applied to the back of the object to be fixed. The protective films on
both sides of one end of the strip should not be removed. After removal of
the protective paper from the other side of the strip, the back of the object
is applied to the surface and pressed thereon.
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To detach the object from the surface, the fingers of the user grip the
end of the strip covered by the protective film and pull in the direction of
the
longitudinal axis of the strip. By virtue of the high elasticity of the
adhesive
material, it increases in length and decreases in width, the pressure-
s sensitive adhesive separating from the wall. Another important aspect of
this process is that the strips are always pulled parallel to the surface. If
the strip is pulled obliquely, it is in danger of tearing.
Although the fixed object can be completely removed from the wall
without destruction using this fixing system and fixing method, force does
have to be applied. In addition, once the object has been applied to the
surface, it is not easy to reposition. Repositioning is often desirable for
aligning pictures, posters etc. on a wall.
In addition, a tape coated on one side is available under the name of
"Duotec" from Binder. On its other side, the tape has mushroom-shaped
projections which extend vertically outwards from the surface of the tape.
These projections are spaced at such intervals apart from one another and
have such a geometry that, when two pieces of the tape are placed with
their adhesive sides on top of one another, the mushroom-like projections
interengage on the lines of a velcro fastener. The particular feature of this
tape is that the corresponding connecting elements in this case do not
differ in shape.
Problem addressed by the invention and solution
Accordingly, the problem addressed by the present invention was to
provide a method of the type mentioned at the beginning for detachably
fixing an object to a surface which would enable both the object and the flat
material to be completely and nondestructively removed without significant
application of force. In addition, the fixed object would be able to be
repositioned on the surface simply, quickly and conveniently.
According to the invention, the solution to this problem in the method
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mentioned at the beginning is characterized in that both flat materials are
joined together at their ends to form only one flat material and, in
particular,
are in one piece, in that the flat material is coated on one side with the
pressure-sensitive adhesive and, on its other side, comprises the
connecting elements, the connecting elements which lie on top of one
another when the flat material is folded corresponding with one another to
interlock the sides lying on top of one another, and in that part of the side
of
the flat material coated with pressure-sensitive adhesive is stuck to the
object and another part of that side of the flat material is stuck to the
surface and the flat material is folded in the manner mentioned either
before or afterwards.
Although the flat material may assume any shape, it is preferably in
the form of a tape.
According to the invention, the flat material may be prefolded by the
manufacturer so that the user need only apply the outer sides coated with
pressure-sensitive adhesive on the one hand to the object and on the other
hand to the surface. The order of application is not important. Normally,
however, the flat material is first applied to the back of the object and then
to the surface. However, the reverse order is also possible in accordance
with the invention.
In the interests of simplicity, the following description refers to a tape
although the invention is by no means confined to this particular geometric
form.
The method according to the invention affords a considerable
advantage over the prior art discussed in the foregoing.
Firstly, an object can be detachably fixed to a wall.
Secondly, complete and nondestructive detachment without
significant application of force is possible as follows: the object is
unfolded
from the wall by separating the corresponding connecting elements from
one another (the angle of the folded tape is 0°, the angle of the fully
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unfolded tape 180°). By then pulling in a direction perpendicular to
the
surface or at an angle of < 90°, that part of the tape adhering to the
surface
can be completely peeled off the wall. Since the force for detaching the
tape is directed at least partly perpendicularly away from the surface, the
5 pressure-sensitive adhesive adhering to the tape is completely removed
from the surface.
Another advantage over the "tesa Poster Strips" and "tesa Power
Strips" is that the areas provided with a non-removable protective film, the
so-called "leaders", in those strips are no longer necessary. In the known
adhesive tapes, these leaders must project beyond the object to be fixed
so that they can be gripped by the hand of the user. This results in an
unattractive appearance. In addition, if alternatively a foldable object, for
example a two-piece towel hook, is to be fixed with the known adhesive
tapes, disadvantages arise. Although, in this case, the leader can be
completely covered by the object because, to detach the object, the fixed
object can be folded away from the wall to expose the "leader" so that the
leader does not necessarily have to project beyond the fixed object
(instead of unfolding the object, a two-piece object comprising a rail may
also be pushed apart), a large part of the adhesive area is lost to the leader
provided with the protective film. These disadvantages are not present in
the method according to the invention or in the flat material according to
the invention as discussed further below.
Another disadvantage which does not arise in the method according
to the invention lies in the problems involved in the handling of the above-
mentioned adhesive strips provided with a leader. In many cases, the user
is not aware that he/she is not supposed to remove the protective film of
the leader. Since the user is accustomed to removing protective films from
adhesive strips, it happens fairly often that helshe also removes the
protective film from the leader so that the actual advantage of the leader,
namely its function as a handling aid during removal, is lost.
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Thirdly, the method according to the invention enables the object
already stuck to the surface to be repositioned. To this end, the object is
unfolded from the wall through a small angle, the corresponding connecting
elements separating from one another, repositioned and finally pressed
back onto the surface, the connecting elements mentioned re-engaging in
one another and fixing the object to the wall in the chosen position.
In the method according to the invention, the corresponding
connecting elements mentioned may have different shapes. Thus, in one
embodiment, the corresponding connecting elements consist of hooks and
loops of a velcro fastener.
Alternatively, however, the corresponding connecting elements may
also consist of mushroom-shaped pins - of the type already mentioned in
the acknowledgement of the prior art - and loops. For fastening, the
thickened ends of the mushroom-shaped pins engage in the loops.
In another embodiment, however, the two corresponding connecting
elements are of the same shape and more particularly consist of
mushroom-shaped pins. In this case, the connection is established in the
same way as with the known Binder "Duotec" tape. Tapes consisting of
material shaped into parallel waves "phase-shifted" through 180° may
also
be used. A connection is established by pressing the wave peaks exactly
into the wave troughs. Looking from above perpendicularly to the wave
direction onto the wave peaks or troughs, there are webs which may be
angled in relation to the plane of the tape and which thus prevent
accidental separation of the joined parts of the tape.
If two different types of connecting elements are provided, as in
another embodiment of the invention, the other side of the tape carrying the
two different types of connecting elements is transversely divided in two
and, more particularly, is divided into two equal halves, one half comprising
connecting elements of one type and the other half comprising connecting
elements of the other corresponding type. An optimal connection between
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the tape halves is established both when the two halves lie exactly on top
of one another after folding together and when the two halves have to
placed obliquely on top of one another for positioning the object to be fixed.
In another embodiment of the invention, however, the two different
types of connecting elements are applied to the above-mentioned side of
the tape in a certain pattern. This pattern may be a strip or grid pattern. In
this case, a good connection between the two parts of the tape is only
established when the corresponding connecting elements lie on top of one
another. However, if the two halves of the tape are folded together in such
a way that identical connecting elements lie on top of one another, the
object is not fixed. Such a possibility could be of advantage in certain
cases.
The various connecting elements may also be statistically
distributed. Another embodiment of the invention is characterized in that,
instead of the connecting elements to be fitted together, pressure-sensitive
adhesive is used at least on parts of the inside of the tape, the adhesion of
the inner parts of the tape to one another not exceeding 50% of the
adhesion of the outer pressure-sensitive adhesive to the substrates (object
and wall).
The present invention also relates to a flat material, more particularly
an adhesive tape, for detachably fixing an object to a surface, one side of
the flat material being coated with a pressure-sensitive adhesive and the
other side comprising connecting elements of at least one type capable of
interlocking with connecting elements of another corresponding type. One
such adhesive tape is marketed under the name of "tesa Klettband
selbstklebend" by Beiersdorf AG.
To solve the problem stated above, it is proposed in accordance with
the invention that the other side of the above-mentioned flat material
comprise both corresponding types of connecting elements. These types
of connecting elements may be, for example, hooks and loops of a velcro
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fastener known per se.
Again in the interests of simplicity, the following description refers to
a tape or adhesive tape and not to the flat material although the invention is
not confined to this particular geometric form.
Here, too, the corresponding connecting elements may assume
different forms. In one embodiment, the corresponding connecting
elements consist of the hooks and loops of a velcro fastener. In another
advantageous embodiment, the corresponding connecting elements
consist of mushroom-shaped pins and loops, as mentioned in the
foregoing.
The distribution of the two different types of connecting elements on
the other side of the tape may differ according to requirements. In a
preferred embodiment, however, the other side of the tape is transversely
divided in two and, in particular, is divided into two equal halves, one half
comprising connecting elements of one type and the other half comprising
connecting elements of the other corresponding type. The advantages of
such an arrangement were mentioned above.
In addition, in the method according to the invention and the flat
material according to the invention, the flat material may have an elastic
support. In this case, the tape can be removed by pulling at an angle to the
wall of >90°. In another possible embodiment, the "leaders" known from
the prior art relating to these adhesive strips may be provided as long as
the associated disadvantages are taken into consideration. In this case,
the adhesive tape can be removed by pulling parallel to the wall.
Suitable pressure-sensitive adhesives
There is no restriction on the use of the various known types of
pressure-sensitive adhesives. Pressure-sensitive adhesives (PSAs for
short) are adhesives which, in solventless form, are permanently tacky at
20°C and remain capable of adhesion, are largely non-substrate-specific
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and adhere immediately to almost all substrates under light pressure.
Pressure-sensitive adhesives are used almost exclusively for
coating supports, for example paper or films in tape form, adhesive labels
or self-adhesive decorative films. To this end, the actual adhesives are
applied to the supports in the form of solutions, dispersions or even melts.
Low-viscosity solventless reactive systems (polyurethane systems) are also
used for this purpose. After the adhesive has set, the layer of pressure-
sensitive adhesive is present as a thin film on the support and is covered
pending use with suitable antiadhesively finished materials, for example
silicone paper or siliconized polyethylene film. In some cases the pressure-
sensitive adhesive is also applied to the cover material and the adhesive
film formed is transferred to the actual support by reverse coating. The dry
coating weight varies between 4 and 40 g/m2 according to the particular
application and the roughness of the support.
Suitable raw materials for pressure-sensitive adhesives are natural
and synthetic rubbers in conjunction with modified natural resins, phenol
formaldehyde resins or hydrocarbon resins. Besides rubber, polyacrylates,
polymethacrylates, polyvinyl ethers and polyisobutenes are also commonly
used, again usually in combination with resins. Silicone resin pressure
sensitive adhesives are also known for special applications.
Pressure-sensitive dispersion adhesives are mainly based on
polyacrylate dispersions and, in some cases, also on special vinyl acetate
copolymers, resins again generally being added. Besides suitable resins,
two polymer bases, ethylene/vinyl acetate copolymers and
styrene/butadiene or styrenelisoprene block copolymers, which are also
known as thermoplastic rubbers, are mainly used for pressure-sensitive
hotmelt adhesives.
In general, a pressure-sensitive adhesive is made up of a high-
polymer base resin which determines cohesion and specific adhesion and
tackifying resins (so-called tackifiers), the tackifying resin also being
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replaceable in some systems by low molecular weight fractions of the base
polymer. To increase cohesion, the base resin in some systems is
crosslinked after application or vulcanized in the case of rubber-based
pressure-sensitive adhesives.
5
Examples of embodiment
Examples of embodiment of the invention are described in detail in
the following with reference to the accompanying drawings, wherein:
Figure 1 is a front elevation of an adhesive tape according to the
10 invention in the direction of the other side carrying the connecting
elements.
Figure 2 is a side elevation of an object fixed to a wall with the
adhesive tape according to the invention as shown in Fig. 1.
Figure 3 is an elevation corresponding to Fig. 2 during detachment
of the fixed object.
Figure 4 is a section through the adhesive tape according to the
invention as shown in Figs. 1 to 3.
Figure 5 is a section corresponding to Fig. 4 through another
embodiment of the adhesive tape according to the invention.
Figure 6 is a section corresponding to Figs. 4 and 5 through a third
embodiment.
In all the drawings, the same reference numerals have the same
meaning and, accordingly, may only be explained once.
The adhesive tape according to the invention shown in Fig. 1 is
coated with a pressure-sensitive adhesive on the side which is not shown.
The side shown has two regions 1,2, the region 1 carrying hooks and the
region 2 carrying loops of a velcro fastener known per se.
To fix an object 5 to a surface 6 which, in the present case, is a
vertical wall, the adhesive tape 3 is transversely folded together in the
middle so that the two regions 1, 2 stick to one another under the effect of
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the velcro-type fastening. One side of the folded adhesive tape 3 which is
coated with a pressure-sensitive adhesive 4 - shown as a thin line in Fig. 2
- is then applied to the surface of an object 5 to be fixed. The object 5 may
be any of a variety of objects, for example a hook, a clip, a board, a holder,
etc. The side opposite the region 1, which is also coated with pressure-
sensitive adhesive 4, is then pressed onto the surface 6. The object 5 is
now firmly fixed to the wall 6. If its position needs to be altered slightly,
it is
sufficient to raise the object 5 in the direction of the arrow 7, to
reposition it,
to let it back down and to press it onto the surface 6 again.
For detachment, which is illustrated in Fig. 3, the procedure is as
follows:
The object 5 is first raised in the direction of the arrow 7 in the same
way as for repositioning, the connection between the regions 1 and 2 being
broken. The object 5 now raised through an angle of <90° or - with
elastic
tapes - even >90° is pulled in the direction of the arrow 8, i.e. with
a linear
application of force 9. In this way, the region 1 of the adhesive tape,
together with the adhesive adhering thereto, can be completely peeled off
the wall 6 without significant effort.
Various connecting elements on the lines of a velcro fastener are
shown in Figs. 4 to 6. In Fig. 4, the connection is established by hooks 10
and loops 11 and, in Fig. 5, by mushroom-shaped pins 12, the thickened
parts 13 in the form of an ellipsoid engaging in the loops 11. Finally, Fig. 6
shows a connection where the corresponding connecting elements are of
the same shape and both connecting elements comprise mushroom
shaped pins 12 with thickened parts 13 which engage in the empty spaces
between the stalks of the mushrooms of the other region and are
interlockingly held by their thickened parts 13. The corresponding
connecting elements shown in Figs. 4 to 6 are suitable for use with the
adhesive tape according to the invention although other similar connecting
elements acting in the same way may also be used.
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List of reference numerals:
1 region (hook)
2 region (loop)
3 adhesive tape
4 pressure-sensitive
adhesive
5 object
6 surface (wall)
7 a rrow
8 a rrow
9 linear application
of force
10 hooks
11 loops
12 mushroom-shaped pins
13 thickened parts
