WO2011020854A1 - Adhesive tape comprising a tearable release film - Google Patents

Abstract

The invention relates to an adhesive tape (1, 2) comprising a substantially tight release film (3, 4), which in the parallel direction to the longitudinal edge (12) of the adhesive tape (1, 2) has low tear propagation force and comprises guide means, by which a tear line propagates substantially in the parallel direction of the longitudinal edge (12) of the adhesive tape (1, 2).

Description

 Adhesive tape with a tearable release film The invention relates to an adhesive tape having a tearable release film. Such adhesive tapes can be used in particular for sealing joints between assembled components, such as between an outer wall opening and a window or door frame in house building. They have the purpose of optimally sealing the joints with little effort by, for example, after joining the components, are glued on the inside of the wall joints overlapping on the joint edges.

PRIOR ART Adhesive tapes, single-sided or double-sided adhesive, are often provided with a release film, which is applied to the exposed adhesive layer and is pulled off immediately before the processing of the adhesive tape. Such release films protect the adhesive prior to processing the tape and are discarded after removal. They are adhesive-repellent, for example by a non-stick coating, usually from silicone-containing coatings. Usually they are made of PE, PP, polyester or papers.

Furthermore, release films are known which can easily separate or tear further in the longitudinal direction. However, a straight spread of a tear line is not guaranteed over longer distances, ie stretching of more than one meter, especially if the release film is pulled off at an angle to the tear-off direction. If one draws a part of the release film obliquely with a deduction angle of, for example, 45 degrees, then the tear line of such release films is oriented in the direction of the tear-off direction. Also it is not possible the manufacturing process of this Separation films, in particular those of the extension, so well to control that the release film tearing exactly in the longitudinal direction. All this is disadvantageous because the release film tears off obliquely to the longitudinal direction of the adhesive tape and the user has to start several times with the removal of the release film. Peelable release films of adhesive tapes should therefore be allowed to continue evenly in a single piece over the required length with a defined width, so that over the entire tape length a uniformly wide adhesive surface is exposed. Adhesive tapes are known for solving this problem, which have a peelable release film which is singly or multiply slit in the longitudinal direction, that is to say in the unwinding direction of the adhesive tape, for example described in DE 10 031 213 B4. This release film can be peeled off along the slots in discrete steps.

As a result, the adhesive tape is not immediately adhering to the entire width, but only on the part area exposed by the stripped release film strip. This can be an advantage when mounting in corners (for example in the construction sector), for joining two materials or when gluing in tight spaces. The adhesive tape can be applied there more simply by first gluing the exposed part region before the remaining release film is peeled off and a next subregion of the adhesive tape can be glued. The adhesive tape can thus, for example when joining two components, first be correctly positioned on the one component and fixed with the exposed portion, with the remaining release film covering the remainder of the adhesive tape. Therefore, this does not adhere unintentionally and is also protected against contamination, for example by dust. Only when the adhesive tape is to be glued to the second component, the next strip of release film is peeled off and glued the tape to the second component. The bonding of the adhesive tape and the removal of the release film is usually a simultaneous process, ie the processor lifts a small part of the release film from the adhesive at the beginning of the adhesive tape, then sticks the adhesive tape to the substrate and then gradually draws the release film under the adhesive tape a trigger angle, wherein he rubs the tape simultaneously.

This process can also be used in adhesive tapes with slit release films, which is ensured by the straight slot that always a defined by the slot strip of release film is removed from the tape and thus always a lot of adhesive tape is glued.

In order to achieve a straight tear line, regardless of the deduction angle, the adhesive-repellent release film can also be provided with a longitudinal perforation. The disadvantage of perforations lies in the fact that the adhesive layer of the adhesive tape is no longer completely covered and adhesive can escape through these openings, with the windings of the adhesive tape roll adhering to one another or even dirt getting onto the adhesive.

Both the arrangement of slots and perforations in the longitudinal direction across the width of the adhesive tape can be done only at sufficiently large distances from each other. If the width of the adhesive tape strips between the slots is too small, the release film is unstable when peeled off and the individual release film strips fall apart. The same applies to perforated release films. A straight spread of the tear line is no longer guaranteed when the strips are removed, since the release film strips, which adjoin the original tear line, also lift off due to the low adhesion of the narrow release film strips. task

It is an object of the present invention to provide an adhesive tape which is versatile, inexpensive to produce and provided with a release film which is torn off over long distances of more than one meter in the longitudinal direction of the adhesive tape in release film strips whose width can be continuously variably selected can be. In the transverse direction, the release film should be as difficult or impossible to continue.

This object is achieved by an adhesive tape having a release film according to claim 1, a roll having an adhesive tape according to claim 12, a release film according to claim 13, a process for producing an adhesive tape according to claim 14, and a process for producing an adhesive tape according to claim 15. Advantageous embodiments of the invention are claimed in the dependent claims.

The adhesive tape according to the invention has a substantially dense separating film which, in the direction parallel to the longitudinal edge or in the unwinding direction of the adhesive tape, has a low tear propagation force and guide means, through which a tear line propagates substantially in the direction parallel to the longitudinal edge of the adhesive tape.

The adhesive tape according to the invention has the advantage that a tear line in the release film does not move away from its lateral position when it propagates in the longitudinal direction of the adhesive tape because it can not overcome the regions of the release film predetermined by the guide means.

Since the release film is dense, for example, in a roll with adhesive tape, the adhesive of the adhesive layer of the adhesive tape can not escape through the release film and the back of the release film with the surface of the adhesive Bonding tape. This is particularly a problem with adhesive tape having a slot with thick adhesive layer as used on the job site. In addition, the adhesive tape may have a low tear propagation force and / or guide means even in the direction parallel to the longitudinal edge of the adhesive tape. Thus, the entire adhesive tape with release film can be easily and quickly adjusted to a desired width. In a preferred embodiment, the tear line of the release film in its propagation in the direction parallel to the longitudinal edge of the adhesive tape over a withdrawal distance of 2m a maximum deviation less than or equal to 25mm, preferably less than / equal to 10mm, more preferably less than / equal to 5mm and most preferably less than / equal Get up.

The tear line in the release film thus spreads over long distances in a straight line and parallel to the longitudinal edge of the adhesive tape regardless of the deduction angle. As a result, a part of an adhesive tape can first be glued on a long distance before the remainder of the adhesive tape is glued.

In a further preferred embodiment, the mutual distance between the guide means is less than 20 mm, preferably less than 10 mm, more preferably less than 5 mm, more preferably less than 3 mm, even more preferably less than 1 mm and particularly preferably less than 0.5 mm.

These small distances between the guide means, the width of a torn Trennfolienstreifreifens can be varied in a nearly continuous manner. This is of particular advantage in building, where the building materials must be adapted to the local conditions. In a further preferred embodiment, the release film is made of plastic or paper. Plastic is water repellent and therefore can be used in humid environments. Paper is environmentally friendly and cheap in procurement.

In a further preferred embodiment, the guide means are substantially parallel first reinforcing threads.

These reinforcing threads of the release film can be placed very close to each other. This is not possible with the known from the prior art slots and perforations for the reasons mentioned above. Due to the close arrangement, the width of a separating film strip to be peeled off can be varied in a nearly continuous manner. This is extremely advantageous because the width of the release film can be adapted to the respective components to be joined.

In a further preferred embodiment, second reinforcing threads are provided which form a grid with the first reinforcing threads. The first reinforcing threads are more tear-resistant than the second reinforcing threads. The release film is reinforced by the second reinforcing threads also in the transverse direction of the adhesive tape or the first reinforcing threads, which, however, due to their low tensile strength compared to the first reinforcing threads do not affect the advantageous properties of straight tear and low tear propagation of the release film in the longitudinal direction of the adhesive tape ,

In a further preferred embodiment, the diameter of the first reinforcing threads and / or the second reinforcing threads is less than the thickness of the release film. Thus, the reinforcing threads can be completely embedded in the release film and are not distinguished as disturbing elevations on the surface. In a further preferred embodiment, the release film is foamed and the guide means are cavities.

The fact that the cavities are enclosed in a foamed release film, the release film has a homogeneous thickness. Furthermore, the foamed release film can be produced in a particularly simple and cost-effective manner.

In a further preferred embodiment, the guide means embossments. Even embossing can be particularly simple and inexpensive to apply to the film.

embodiments

Embodiments of the invention will now be described in more detail with reference to drawings.

Fig. 1 shows a first embodiment of the adhesive tape with peelable release film. Fig. 2 shows a second embodiment of the adhesive tape with peelable release film.

Figs. 3A and 3B show the construction and execution of a test for evaluation of the propagation of a tear line.

Fig. 4 shows a roll of adhesive tape with a release film.

In Fig. 1, a first embodiment of the adhesive tape 1, 2 is simplified with a release film 3, 4 according to the invention and shown partially cut. The adhesive tape 1, 2 consists of a carrier layer 1 and of an adhesive layer 2 on its underside. Alternatively, adhesive layers 2 could also be arranged on top and bottom of the carrier layer 1 in the case of a double-sided adhesive tape 1, 2. The release film 3, 4 consists of a film 3 with an adhesive-repellent coating 4, preferably a siliconization. In or on the release film 3, 4 are first, substantially parallel reinforcing threads 5, which are firmly connected to the release film 3, 4. Of course, the number of reinforcing threads 5 could be higher or lower than shown.

The backing layer 1 can be made of a nonwoven fabric, a nonwoven coated with plastic, a plastic film, a paper, a coated paper, an aluminum foil, an aluminum-coated plastic film, an aluminum-plastic composite film, a metal foil, a woven fabric, or any combination thereof Materials that are easy to produce, for example, by laminating the materials.

The adhesive layer 2 of the adhesive tape 1, 2 is completely or partially covered with the release film 3, 4. It consists of an aqueous polymer dispersion or a solvent dispersion, a hotmelt, a butyl adhesive, a bitumen adhesive or a combination of these adhesives. The solvent content of the aqueous polymer dispersion is less than 20%, preferably less than 10% and particularly preferably less than 3%. The coating weight of the adhesive of the adhesive layer 2 is in the finished adhesive tape 1, 2, preferably at least 100g / m ^2, preferably at least 150g / m ^2, more preferably at least 500g / m ² and particularly preferably at least 800g / m ^2. It is therefore preferably a thick adhesive layer. The film 3 may be made of a material of the following material group: oriented polyamide (OPA), cast polyamide (CPA), oriented polypropylene (OPP) including bioriented polypropylene (BOPP), high and low density polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS), polymethylmethacrylate (PMMA), polyvinyldichloride (PVDC), polyvinyl difluoride (PVDF) , Polyethylene naphthalate (PEN), polyesters including polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), terpolymer- acrylonitrile-butadiene-styrene (ABS), polycarbonate (PC). Furthermore, the film 3 can also consist of any combination of the above material groups, which is produced for example by formulations (blend) or laminations.

The film 3 can be produced by the customary processes, such as blown film extrusion, coextrusion or cast extrusion. Also, the production by calendering possible. The release film 3, 4 can be adjusted with a reduced tearing force in the longitudinal direction, so that it can be torn in this direction by hand. This reduced tear propagation force can be achieved by mechanically stretching the film 3, optimizing the blend of HDPE, LDPE, LLDPE, the use of oriented polyamide (OPA), oriented polypropylene (OPP) including bioriented polypropylene (BOPP), or calcium carbonate.

For metrological evaluation of this property, the tear propagation forces of the release film 3, 4 in the machine direction [md] or in the longitudinal direction of the adhesive tape, and transversely to the machine direction [cd] or in the transverse direction of the adhesive tape, compared.

The measurements of the tear propagation force are carried out according to DIN 53356. The ratio of tear propagation forces in [md] and in [cd] is evaluated. The ratio of the tear propagation force in [cd] divided by the tear propagation force in [md] is greater than 5, preferably greater than 10 and particularly preferably greater than 15. The thinner the separating film 3, 4, the lower the further tearing force to be expended. The release film 3, 4 is dense, ie, adhesive of the adhesive layer 2 of the adhesive tape 1, 2 can not pass through the release film 3, 4. This is, as mentioned above, a problem with release films with perforations and slots.

If paper is used instead of plastic as film 3, papers are particularly suitable as they are already used today as starting materials for silicone papers. Papers have by themselves a low tear strength along the fibers. The combination of a paper with plastic may be suitable for the production of the film 3. The adhesive-repellent coating 4 can be applied to the film 3 on one or both sides. As the adhesive-repellent coating 4, silicone, wax or polytetrafluoroethylene (PTFE) can be used. The preferred coating weight of the adhesive-repellent coating 4 on each side, which is coated, is less than 6 g / m ^2, preferably less than 4 g / m ² and particularly preferably less than 3 g / m ^2.

The thickness of the release film with adhesive-repellent coating 3, 4 is 10 m ^"6 to 300 m ^{" 6} , preferably 15 m ^"6 to 200 m ^{" 6} and particularly preferably 20 m ^"6 to 150 m ^{" 6} . The thickness measurement is carried out according to DIN 53370: 2006-11. Measured at 23 ° C. To determine the thickness, the average is calculated from five measurements.

The guide means are first reinforcing threads 5 in this embodiment. These first reinforcing threads 5 determine the course of the longitudinal crack and prevent the crack from spreading through a channel formed by two adjacent first reinforcing threads 5. Preferably, particularly tear-resistant threads are used. The first reinforcing threads 5 are generally plastics, aramid (aromatic polyamide), carbon and glass fibers, PP or polyester are particularly suitable. But also textile threads of rayon or viscose or cotton, or a combination thereof can be used. Thin metal wires can also be used.

Further suitable materials for the first reinforcing threads 5 are the typical chemical fibers such as Teflon, Bekitex, carbon, glass, basalt, carbon, ceramic, Kevlar, Nomex, polyamide, polyimide, polyamideimide, polyphenylene sulfide, polyacrylonitrile, Twaron or viscose , Alternatively, natural fibers may also be used, e.g. Cotton yarns, flax, longsleeve, hemp, jute, ramie and sisal. Likewise, metal fibers can be used in the form of very thin wires. Combinations of the materials mentioned can be used.

The thickness of the first reinforcing threads is preferably greater than 50 dtex, more preferably greater than 100 dtex, and most preferably greater than 150 dtex.

The first reinforcing threads preferably have a tear strength of greater than 30 cN / tex, more preferably greater than 50 cN / tex and most preferably greater than 60 cN / tex to DIN EN 10204.

The first reinforcing threads 5 are also not limited to threads in the true sense. Rather, these may be any type of continuous reinforcement such as a tape, a strip or a thickening of the film material. The tear strength of the first reinforcing threads 5 is preferably to be selected higher than the tear strength of the release film 3, 4.

The distance between the first reinforcing threads 5 is preferably less than 20 mm, more preferably less than 10 mm, more preferably less than 5 mm, more preferably less than 3 mm, even more preferably less than 1 mm and particularly preferably less than 0.5 mm. The distances of the first reinforcing threads 5 need not be uniform but may vary across the width of the release film 3, 4. Although the reinforcing threads 5 should be arranged substantially parallel to one another, the distance between the reinforcing threads 5 can also vary slightly in the direction parallel to the longitudinal edge 12 of the adhesive tape 1, 2.

In use, a release film 3, 4 described above is torn at one edge between two first reinforcing threads 5: When a force with a peel angle α on the release film 3, 4, the tear line extends longitudinally along a first reinforcing thread 5 or between the two first reinforcing threads 5, the left and right boundaries of the tear line form, from. Within these adjacent first reinforcing threads 5, the tear line can move freely, even at arbitrarily oblique trigger angles α. The first reinforcing threads 5 may be 5 mm apart, for example. Then the release film 3, 4 at intervals of a minimum of 5 mm arbitrarily further torn in the longitudinal direction and be removed from the tape step by step. If a distance of the first reinforcing threads 5 of 2 mm is selected, cracks can be generated at a distance of a minimum of 2 mm from each other.

To produce the release film 3, 4, the film 3 is first produced with first reinforcing threads 5. For this purpose, the first reinforcing threads 5 are at a regular or irregular distance substantially parallel to each other in the direction parallel to the later longitudinal edge 12 of the adhesive tape (1, 2) arranged. The thickness of the first reinforcing threads 5 is preferably thinner than the film 3 to choose. Thus, the film 3 can be made in a uniform thickness. Then, the first reinforcing threads 5 are firmly bonded to the film 3. They are, for example, cast into the film 3 by means of a melting process or, after the film 3 has been produced, are joined to the film 3 by means of a melting, adhesive or pressing process.

Another possibility in the production of the film 3 with first reinforcing threads 5 is the direct extrusion of the film 3 onto the first reinforcing threads 5.

Subsequently, the first reinforcing threads 5 can be additionally laminated with a further film 3. This lamination can be achieved by thermal processes, adhesions or another extrusion coating. As a result, the surfaces are smoother and the first reinforcing threads 5 better integrated.

An arrangement of the first reinforcing threads 5 with thermally unstable transverse threads is possible, which ensure that the first reinforcing threads 5 remain aligned parallel to each other. These transverse threads are thermally unstable and can be partially or completely destroyed by heating during or after the production of the film with first reinforcing threads 5.

By applying an adhesive-repellent coating 4, the release film 3, 4 with first reinforcing threads 5, which is suitable for covering the adhesive layer 2 of adhesive tapes 1, 2, is finally produced.

A second embodiment of the invention, illustrated in FIG. 2, differs from the first embodiment in that the release film 3, 4 comprises, in addition to the first reinforcing threads 5, second reinforcing threads 6 which form a grid with the first reinforcing threads 5. This grid can also be designed as a scrim, fabric or braid. The first amplifiers Kung threads 5 to the second reinforcing threads 6 may be arranged at an arbitrary angle.

Basically, the second reinforcing yarns 6 may be formed the same as the first reinforcing yarns 5. However, a preferred combination is a high tear strength material for the first reinforcing yarns 5 and a low tear strength material for the second reinforcing yarns 6, such as cell wool. Also, the second reinforcing threads 6 may be made thinner than the first reinforcing threads 5.

The reduced tear strength of the second reinforcing yarns 6 can firstly by the choice of less stable materials (eg viscose or long flax) of the second reinforcing yarns 6 compared to the first reinforcing yarns 5 and on the other by a smaller thickness of the second reinforcing yarns 6 in comparison to the first reinforcing threads 5 can be achieved.

The second reinforcing threads 6 simplify the incorporation of the first reinforcing threads 5 into the release film 3, 4. Thus, with the aid of the second reinforcing threads 6, the first reinforcing threads 5 can be incorporated in the release film 3, 4 in the form of a grid or slip.

For example, a suitable grid or scrim consists of 165 dtex high-strength polyester yarn for the first reinforcing threads 5 and 80 dtex viscose for the second reinforcing threads 6.

For a third embodiment of the invention are used as a guide means instead of the first reinforcing threads 5 in the release film 3, 4 cavities, which are introduced by means of a foaming process in the film 3. This film 3 with cavities has a high tear propagation force in [cd], ie transversely to the machine direction or in the transverse direction of the adhesive tape. The foaming process produces 3 voids in the film. The cavities cause a weakening of the film 3, which leads to a simplified crack line formation. The spread of this tear line in the finished release film 3, 4 is then oriented to these cavities.

These cavities may additionally be oriented longitudinally by a special manufacturing process.

Here one makes use of an effect which resembles the tearing of a perforated foil. The cavities form chains, which correspond to a perforation line through a film, and along which the release film 3, 4 further tears when it is torn at one edge and a tear propagation force on the release film 3, 4 acts. In the production of a film 3 of the third embodiment, a cast extrusion method is preferably used. The foaming is ensured either by appropriate additions to the material raw material prior to extrusion or by supplying blowing agents in the extrusion process, for example using tandem extruders.

As supplements to the material raw material for foaming, for example, mixtures of hydro gencarbonaten and inorganic or organic acids such as citric acid, or other foaming or blowing agents can be used. Examples of suitable blowing agents are the classes of compounds or derivatives of azodicarbonamide (ADC), o-, m-, p-toluenesulfonic acid (TSH), oxi-bis-sulfo-hydrazide (OBSH), 5-phenyltetrazole (5 PT), benzene-sulfo-hydrazide (BSH), and para-toluene-sulfonyl-semicarbazide (PTSS). As foaming agents or blowing agents, the products of the company Lanxess of the product groups Genitron® and Porofor®, as well as the products of the company Tramaco of the product group Unicell® and their blends are listed here by way of example and purely by way of example. Examples of blowing agents which are fed during the extrusion process, ie in the presence of a polymer melt, are exemplified by pentane, carbon dioxide, air or constituents thereof and noble gases.

Of course, other suitable blowing agents could be used to make the foamed sheet 3.

In addition, subsequent mechanical foaming by blowing in air or inert gases into the melt is also possible.

The extruded, foamed film 3 can subsequently be guided over rolls in the machine direction [md] or longitudinal direction at increasing speed, resulting in stretching of the film 3 in this direction. This further leads to an orientation of the cavities.

As a result of this orientation, the tear propagation force in the machine direction [md] or in the longitudinal direction of the film 3, which later also forms the longitudinal direction of the release film 3, 4 or the parallel direction to the longitudinal edge 12 of the adhesive tape 1, 2, compared to the tear propagation force in [cd] or additionally reduced in the transverse direction.

The property of preferential propagation of a longitudinal crack line of the release film 3, 4 or parallel to the longitudinal edge 12 of the adhesive tape 1, 2 is proportionally increasing with the degree of stretching of the film 3 in that direction.

In a fourth embodiment, the guide means embossments, which are introduced for example by a calendering process in the release film 3, 4. These embossing act as tearing of the release film 3, 4 as a kind of predetermined breaking point, along which propagates the tear line. One possibility for realizing the inventive release film 3, 4 would also be to use a foamed sheet 3 according to the third embodiment and to provide these additionally with embossing according to the fourth embodiment. Another possibility would be the combination of a foamed sheet 3 according to the third embodiment with first and / or second reinforcing threads 5, 6 according to the first or second embodiment.

Another way to produce the film 3 is to produce them in the casting process with a special extrusion die. This extrusion die is either narrowed or expanded across its width.

If the extrusion nozzle is narrowed at one point, weakenings in the film 3 are deliberately introduced at this narrowing due to the lower release of film material. These weakenings correspond to the guide means on which the tear line in the release film 3, 4 later spreads preferentially.

If the extrusion die is widened at one point, the foil 3 is purposefully reinforced by the increased release of foil material. These reinforcements are then also used in the release film 3, 4 as a guide.

For metrological evaluation of the properties of the release films 3, 4 according to the above embodiments, the tear strength is measured in each case and evaluated the spread of a tear line.

The measurements of the tear propagation force are carried out according to DIN 53356.

The tear propagation force is the force required to cause the propagation of a tear line from a tear. The tear propagation force of the release film 3, 4 in the direction parallel to the longitudinal edge 12 of the adhesive tape 1, 2 is less than 30N, preferably less than 25N, more preferably less than 2ON, even more preferably less ION, more preferably between 0.1N and 30N, and more preferably between 0, IN and 2ON.

The parallel direction to the longitudinal edge 12 corresponds to the longitudinal direction of the adhesive tape 1, 2 or the direction of the guide means and the unwinding direction C of an adhesive tape 1, 2 when wound on a roll 13, as exemplified in FIG.

The evaluation of the propagation of a tear line is done with a test in which the maximum deviation of a tear line from a crack on a tear distance of 2 m, independent of the take-off angle, is determined.

The test is carried out at test conditions of 23 ⁰ C and 50% relative humidity. The test samples are to be acclimatised for 24 hours in the test climate.

The test setup is as follows and is shown in Fig. 3A. The release film 3, 4 to be tested is designed flat on a flat surface and fixed to the three non-tested release film edges on the substrate with adhesive tape 7. At the separating film edge 8 to be tested, a line 9 parallel to this is marked at a distance of 40 mm from the separating film edge 8 over a 2.6 m long test section. The marking 9 takes place with a felt-tip pen or marker which exerts no pressure on the release film 3, 4 and can not cause any mechanical damage to the release film 3, 4.

The test procedure is as follows and is shown in Fig. 3B. The release film 3, 4 to be tested is cut on one side over a length of 0.1 m on the marking 9 of the test section (5). This section 10 corresponds to the crack. The 100 mm long and 40 mm wide release film strip 11 produced by the tear 10 is now oriented to the rest of the release film, that between the both edges produce a take-off angle α. The take-off angle α is set between 10 ° and 180 ° with an accuracy of +/- 3 ° and increased per test procedure in increments of 10 °. In total, 18 measurements are carried out for the test.

The 40 mm wide release film strip 11 is pulled away from the rest of the release film 3, 4 while maintaining the take-off angle α (pulling direction A), at the same time the tear line 10 in the test direction B spreads out. The withdrawal path of 2.5m length must be covered evenly in 6 seconds, +/- 1 second. This corresponds to a uniform take-off speed of 0.36 to 0.5 m / s.

The measurement distance to evaluate the propagation of the tear line begins only 0.3m after the tear 10. The first 0.3m after the tear are therefore not included in the evaluation.

The characteristic of propagation of a tear line in the direction parallel to the longitudinal edge 12 of the adhesive tape 1, 2 is confirmed when the maximum deviation of the tear line 10 from the tear 10 and the mark 9 is less than or equal to 25 mm over the measuring distance of 2 m, independently the trigger angle α. More preferably, the maximum deviation is less than or equal to 10 mm, more preferably less than / equal to 5 mm and particularly preferably less than / equal to 1 mm.

The adhesive tape 1, 2 with separating film 3, 4 can be produced in strips or wound onto a roll 13, the adhesive tape length on such a roll 13 being at least 5 m, preferably at least 10 m, more preferably at least 15 m, even more preferably between 1 m and 100 m and more preferably between Im and 60m. The width of the adhesive tape 1, 2 is at least 3 cm, preferably at least 5 cm, more preferably at least 6 cm and particularly preferably at least 10 cm. Such a roller 13 is shown by way of example in FIG. 4. In widths of at least 50 cm and lengths of at least 10 m, the adhesive tape 1, 2 can also be used as a roofing membrane.

The release film 3, 4, which was described in the preceding embodiments, is not limited to use with an adhesive tape 1, 2. It can also be used in other fields where a film having the above properties is needed, for example, in the field of home renovation cover films. LIST OF REFERENCE NUMBERS

1 carrier layer

 2 adhesive layer

 3 foil

4 adhesive-repellent coating

 5 first reinforcing threads

 6 Second reinforcing threads

 7 tape

 8 Release sheet edge to be checked

9 mark

 10 cut / tear

 11 separating film strips

 12 longitudinal edge of the adhesive tape 1, 2

 13 roll

A pulling direction

B test direction

C rolling direction

Claims

 1. Adhesive tape (1, 2) with a substantially dense separating film (3, 4), which in the direction parallel to the longitudinal edge (12) of the adhesive tape (1, 2) has a low tear propagation force and guide means, through which a tear line substantially in the direction parallel to the longitudinal edge (12) of the adhesive tape (1, 2) propagates. 2. Adhesive tape (1, 2) according to claim 1, wherein the tear propagation force of the release film (3, 4) in the direction parallel to the longitudinal edge (12) of the adhesive tape 1, 2 lower 30N, preferably less 25N, more preferably less 2ON, even more preferably low ION, more preferably between 0.1N and 30N and more preferably between 0.1N and 2ON. 3. adhesive tape (1, 2) according to claim 1 or 2, wherein the tear line of the release film (3, 4) in their propagation in the direction parallel to the longitudinal edge (12) of the adhesive tape (1, 2) over a measuring distance of 2m a maximum Ab - Softing less than / equal to 25mm, preferably less than / equal to 10mm, more preferably less than / equal to 5mm and more preferably less than / equal to lmm. 4. Adhesive tape (1, 2) according to one of the preceding claims, wherein the mutual distance between the guide means less than 20mm, preferably less than 10mm, more preferably less than 5mm, more preferably less than 3mm, even more preferably less than 1mm, and most preferably less than 0.5mm. 5. adhesive tape (1, 2) according to any one of the preceding claims, wherein the release film (3, 4) made of plastic or paper. 6. Adhesive tape (1, 2) one of the preceding claims, wherein the guide means are substantially parallel first reinforcing threads (5). 7. adhesive tape (1, 2) according to claim 6, wherein second reinforcing threads (6) are provided, which form a grid (5, 6) with the first reinforcing threads (5), wherein the first reinforcing threads (5) are more tear resistant than the second Reinforcing threads (6). 8. adhesive tape (1, 2) according to claim 6 or 7, wherein the diameter of the first reinforcing threads (5) and / or the second reinforcing threads (6) is smaller than the thickness of the release film (3, 4). 9. adhesive tape (1, 2) according to any one of claims 1 to 8, wherein the release film (3, 4) is foamed and the guide means are cavities. 10. Adhesive tape (1, 2) according to claim 9, wherein the cavities stretched and in the direction parallel to the longitudinal edge (12) of the adhesive tape (1, 2) are oriented. 11. An adhesive tape (1, 2) according to any one of claims 1 to 10, wherein the guide means are embossed. 12. roller (13) with an adhesive tape (1, 2) with a release film (3, 4) according to any one of the preceding claims, wherein the tape length is at least 5m, preferably at least 10m, more preferably at least 15m, even more preferably between 1m and 100m and more preferably between see Im and 60m. 13. release film (3, 4), which is configured according to the features of one or more of claims 1 to 11. 14. A method for producing an adhesive tape (1, 2) with a peelable release film (3, 4) according to any one of claims 6 to 8, comprising the following steps:  Providing the adhesive tape (1, 2);  Providing a film (3);  Providing first reinforcing threads (5) in a parallel arrangement; Bonding the substantially parallel first reinforcing threads (5) to the film (3) by extrusion, melting, bonding or pressing methods; Applying an adhesive-repellent coating (4) to the film (3); and  Assembly of the release film (3, 4) with the adhesive tape (1, 2). 15. A process for producing an adhesive tape (1, 2) with a peelable release film (3, 4) according to claim 9, comprising the following steps:  Providing the adhesive tape (1, 2);  Foaming of a film (3);  Stretching the film (3);  Applying an adhesive-repellent coating (4) to the film (3); and  Assembly of the release film (3, 4) with the adhesive tape (1, 2).