ES2200422T3 - ADHESIVE TAPE DISPENSER BLADE. - Google Patents

Abstract

DISPENSED BLADE FOR STICKER BAND EXPENDER, SPECIALLY COMPOSED OF A BOX, A WINDING NUCLEUS RECEPTION AND A STICKED BAND SUPPORT DISPOSED BEFORE THE DISPENSED BLADE. THE DISPENSED BLADE CONTAINS A BLADE CUTTING, THAT SHOWS A WAVED SHAPE, WITH CONVEXED ROUND CUTTING TEETH WITH REFERENCE TO THE PEGATED FILM SUPPORT AND CONCAVED ROUNDED AREAS BETWEEN ADJACENT CUTTING DIES, IN THE AREAS AND IN THE AREAS TOOTH BASE. LINEAR AREAS ARE EXTENDED BETWEEN TOOTH TOOTH AND TOOTH BASE AT LEAST 69% OF TOOTH HEIGHT, PREFERRED TO AT LEAST 30% OF TOOTH HEIGHT, SO THAT THROUGH TEETH TOOTH CUTTING AWAY THE CUTS GENERATED IN THE STRIPS OF PAYING BAND ARE POSSIBLY GUIDED ACCORDING TO THE KNIFE CUTTING CONTOUR OF SUCH MODE, THAT GENERATES THE DEVELOPMENT OF ONE ON ANOTHER IN THE FORM OF APPROXIMATION, WITH WHICH NO DEVELOPMENT IS GENERATED ONLY INSIGNIFICANTS IN THE LONGITUDINAL ADDRESS OF THE STRIPPED BAND STRIP AND CAN BE RELEASED AGAIN FROM THE PAINED BAND PIECES BELOW BEFORE THE IMPECCABLE PATCH SUPPORT.

Description

Blade for adhesive tape dispenser.

The invention relates to a blade for known adhesive tape dispensers.

Unwinders for rolls of adhesive tape, also called dispensers, they serve the user as a container to store the rolls of the adhesive tape itself and as a means of application when working with her. The main object of a adhesive tape dispenser consists of taking out and cutting shape simple, easy and clean strips of duct tape length required for each intended application. The embodiments Typical dispensers comprise a carrier box as an element base, a housing for the core of the roll, a deposit of masking tape and a cutting or tearing device. As forms of Basic realization are distinguished:

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Dispenser generally very compact (hereinafter referred to as compact dispenser), formed by an open or closed box that may present, laterally, a round, trapezoidal shape, rectangular or polygonal The roll of adhesive tape is arranged to its application in a roll core housing, integrated approximately in the center of the box. Laterally, the dispenser has a slot-shaped exit space through the that the adhesive tape is removed for later cutting. Usually, on one side of the exit slot is the blade with which you can cut a piece of adhesive tape from the desired length The part of the outlet opposite the blade is generally used as a support surface for the side self-adhesive adhesive tape, and is developed in such a way that the piece of self-adhesive tape stuck on it can peel off easily

An example of how to realization of this type of dispenser can be found in the WO 95/28108.

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Dispenser in which the box, open or closed, that houses the roll of tape adhesive is separated locally from the support elements of the Adhesive tape and cutting blade. These dispensers find Multiple applications such as manual and desktop dispensers. Although less compact, they have the advantage that the tape adhesive can be removed quickly and easily, being possible, in addition, its use with one hand.

An example of how to realization of this type of dispenser can be found in the US 4,059,210.

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Dispenser in which the necessary adhesive tape can be transferred directly on the substrate, by means, for example, of a guide roller that acts at the same time as a tightening roller (hereinafter referred to as a transfer dispenser). For him cutting, a knife is arranged in front of the tightening roller cutter or similar device, by means of which it can be cut the adhesive tape, for example, performing a small movement of dispenser rotation.

An example of how to realization of this type of dispenser can be found in the WO 96/06790.

To cut a piece of duct tape from the desired length the corresponding piece of adhesive tape is removed and cut by the blade. The shape and materials of a Suitable blade may vary.

In most cases, the blades They have a serrated edge. In injection molded dispensers, the serrated edge can be manufactured during the process of injection (see, for example, the Tesa tape unwinder 55975-87) In addition, it is usually integrated into the dispenser a metal cutting blade. Metal blades they have the advantage over the plastic toothed edges of possess, generally, a greater mechanical resistance and be more sharp, so they last longer and have a versatility of uses greater in terms of materials to be cut (for example, with respect to thickness and type of sheets).

The usual embodiments of cutting edges sharp include in its front view:

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A serrated base structure with adjacent cutting teeth, generally triangular. An example of embodiment of This type is shown in Figure 5a.

The cutting edge can present in the area of the tips of the teeth (51) and / or the bases of the teeth (52), in the transition zone between teeth contiguous, a pointed or more or less rounded shape. Generally, the zones (53) located between the toothed tips (51) and the bases of the teeth (52) are designed approximately rectilinear

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Blades comb-shaped sharp An example of embodiment of This type is shown in Figure 5b.

In this case, the teeth contiguous have a separation distance at their base determined. Individual teeth can have a width approximately equal in all its height or narrow on its part higher. An extreme case is represented by sharp edges Finished at the end of the teeth. Likewise, the cutting teeth may be more or less rounded by the area of the jagged tips (51) and / or in the transition zone between the teeth and their bases (52). Generally, the zones (53) of the tips serrated (51) to the bases of the teeth (52) can again be constituted approximately rectilinear.

To achieve sufficient cutting capacity, the blades can be optionally beveled by their area higher. The beveled part may have a constant angle or be rounded in the area of sharp teeth.

In the document DE-U-89 04 789 is shown as example a dispenser blade for a tape dispenser adhesive, including the dispenser blade a cutting edge with a toothed base structure with triangular cutting teeth in a row. The edge ends in a point in the area of the tips teeth and at the base of the teeth, in the transition zones between adjacent teeth, not being arranged in a way of realization, in the same plane the jagged tips.

The usual methods of manufacturing dispenser blades include die cutting, grinding and Wire EDM. For steel cutting blades hardened, the shape of the teeth is usually done by grinding (for example, in the unwind of Tesa 56210) or by wire EDM. Grinding takes place, for example, at an acute angle of 30º with respect to the plane of the cutting blade to achieve sufficient cutting power.

For dispenser blades made using a die-cutting process, for example, qualities of strap K 40 and K 60. The die angle is usually 90º with respect to the plane of the cutting blade (running so vertical with respect to said plane), as, for example, in the manual winding of Tesa 5003. In the die cutting process, a pattern burr usually develops correspondingly perpendicular to the cutting plane.

To get a smooth cut of the strips of adhesive tape the cutting blades are placed in the dispenser with an angle of incidence of, for example, 45º with respect to the plane of the sheet.

With the cutting blades described previously bands can be cut excellently Classic self-adhesive with PVC support, such as Tesa tape 4104 or 7121. A resumption without residues of the corresponding Adhesive strips are equally possible without exception.

A disadvantage of dispensers provided with serrated cutting blades is that, especially in self-adhesive tapes that use support materials with a reduced resistance to progressive tearing and low ductility, these cannot be detached without any tear over many substrates This applies especially for adhesive tapes, widely used today, which employ very stretched sheets biaxially oriented on a basis of PP homopolymers as support, but also for very stretched sheets on the basis of other very crystalline polyolefins as well as for biaxial PETP stretched, to name just a few.

In the use of a dispenser blade with serrated edge, the contour of the blade (serrated contour) is reproduce better or worse at the cutting edges of the piece of tape adhesive cut during the cutting process of an adhesive band according to the quality of the cut. Thanks to the type of cutting edge sharp and sharp burrs or other, frequent damage in these blades, small tears are often obtained in the cutting edges of the strip of adhesive tape obtained.

As a consequence of this reproduction of the structure of the teeth and tears mentioned in the cutting edges of adhesive film strips, often subsequent attempts by the user to peel off the strip of Adhesive tape attached to the substrate in one piece. So correspondingly, the strips of adhesive tape obtained are torn much more often when trying to peel them off depending on the edges cutting obtained with the cutting blade.

Consequently, it is often necessary to be able to completely detach individual strips of adhesive tape, scratch it from the substrate, which takes time and effort. How consequently, it is not excluded that remain of adhesive tape or of adhesive paste difficult to remove or damage substrate on which the adhesive tape was pasted.

It is advantageous in any case, to make a easy cutting, the use of a cutting blade sufficiently sharp. This applies to transparent self-adhesive films, especially for materials with high resistance to tear, such as monoaxial or biaxially oriented polypropylenes, as well as for them on a basis of polyethylene terephthalate.

The force needed to cut a piece of tape Adhesive increases, in general, significantly, with the thickness of the film and with the decrease in the degree of stretch of the same.

By using cutting blades very sharp and smooth edges can take off, in general, easily and without tearing the self-adhesive films mentioned, since in this case there is no damage to the cutting edges in shape of tears and, thanks to the high sharpness, can be cut movies difficult to cut in other cases. So, the overwhelming of Tesa de desktop 6082 uses a smooth cutting blade that enables a completely rectilinear cutting edge of the tape adhesive to cut. Strips of masking tape cut by Tesa 6082 desktop overwhelmer, which use a PP holder biaxially oriented, they can take off in virtually all the cases without any tear.

However, injuries cannot be ruled out, especially of the fingers, in the use of the dispensers mentioned. US 4,175,685 describes a dispenser of adhesive tape that uses a cutting unit that contains a razor blade. To avoid injuries, you have around the blade a filamentous material of shape flexible helical The razor blade can be accessed by between the individual windings of this material. A Tesa 6080 industrial coiler a smooth blade of cross section integrated in a cutting rod. Thanks to the special arrangement and orientation of the cutting blade by below the cutter rod the risk of Injuries to the user. The automatic device Tesa 6056 also uses an oblique blade with respect to the adhesive tape It is controlled electromagnetically. In the same way the maximum risk of injury to the user.

The disadvantage of the dispensers of mentioned adhesive tape, with straight and straight cutting edges of high cutting power, lies in the risk of injuries that entails the blade in case there is no protective cover, in addition to that additional steps are required in the process due to the protective cover must be removed or lifted manually to use the adhesive tape. In the case mentioned before the blade is released automatically while using the device, a construction of the adhesive tape dispenser often more complex, which implies an increase in manufacturing costs and volume of the device, and can also reduce its ability to functioning.

The objective of the invention is to provide solutions to especially develop a blade of adhesive tape dispenser, which can easily integrate into the cutting device currently known toothed metal or plastic dispensers in its known embodiments, which may result in an edge cutting on the adhesive tape of such a nature that the piece of adhesive film can peel off without tearing, especially as which refers to adhesive films with a backing sheet on a monoaxial or biaxially oriented polypropylene base, that has a high cutting power for adhesive tapes to cut without representing a significant risk of injury compared to the classic dispenser blades provided of serrated cutting edges, and that are not expensive in their realization.

This goal is achieved through a dispenser blade as characterized in the claim principal. Advantageous embodiments of the blade of dispenser according to the invention are subject to subclaims

Accordingly, the invention relates to a Dispenser blade with a wavy cutting edge devoid of intervals or with few linear intervals between serrated tips and bases of teeth, with

shapely rounded cutting teeth convex e

rounded concave intervals between adjacent cutting teeth

with respect to the adhesive tape holder, of such so that the cuts obtained by contiguous cutting teeth in the strips of adhesive tape extend along the edge of the edge shear that runs approximately one inside the other, not producing no, or producing few tears in the direction longitudinal strips of adhesive tape cut and rotting, subsequently, take off without tears of the substrate on which have glued, the height of the teeth being preferably lower or equal to the separation distance between the tips of the teeth, obtaining a high cutting power of the blade thanks to a optional pattern burr on the toothed contour, especially at the tips of the teeth, being able to control the undulation of the cutting profile using the angle of incidence of the blade cut. In this case, the tips and bases of the teeth are they find in the same flat.

Without attempting to unnecessarily limit the invention, embodiments are set forth below advantageous of the dispenser blade referring to the Several figures attached.

Figure 1 shows a cutting device (11), according to the invention, which comprises a support surface of the film (12), on whose front face (face for which a piece of cut tape) a cutting blade is integrated toothed (14).

The tips of the teeth run in a way approximately parallel to the front face of the cutting device and parallel to the supporting surface of the film (12). In the sides of the film support surface (12) are optionally find nerves (13). The support surface of the film (12) advantageously occupies a surface so wide enough to ensure a secure fixation of the adhesive film during the cutting process and avoid especially the sliding of the adhesive tape over the blade during the cutting process.

The blade (14) is thus arranged in relationship with the height of the support surface than the tips of the teeth are arranged approximately 2 mm below 3 mm above it, preferably 0.3 to 1 mm above Of the same. The separation of the blade from the surface Support is approximately 0.1 to 5 mm, preferably 0.2 to 2 mm and especially preferably from 0.3 to 1 mm.

Figure 2 schematically shows the form of The cutting blade. The blade edge is distinguished because its travel between the tips of the teeth (21) is rounded. The Teeth tips (22) also have a profile rounded.

The separation (23) between tooth tips contiguous is approximately 0.3 to 4 mm, preferably 0.5 to 3 mm, and especially preferably 1 to 1.5 mm. The height (24) of the teeth, measured between the bottom point of the profile (21) and the tips of the teeth (22), is approximately 0.15 to 2 mm, preferably 0.2 to 1.5 mm, and especially preferably from 0.3 to 0.7 mm. Preferably, the height (24) of the teeth, measured between the bottom point of the profile (21) and the tips of the teeth (22), is less than the separation (23) between tips of contiguous teeth, and especially preferably less than the half of the separation between tips of adjacent teeth.

Preferably, the blade profile of cut according to the invention is regular, that is to say that neither the separation between teeth neither the height nor the shape of the teeth varies within of the cutting blade.

The radius of curvature of the tips of the teeth (22) is approximately 0.05 to 0.7 mm, preferably of 0.07 to 0.4 mm, and especially preferably 0.1 to 0.25 mm. The radius of curvature of the profile between the tips of the teeth it has values between approximately 0.1 and 2 mm, preferably between 0.15 and 1.4 mm, and especially preferably from 0.25 to 0.7 mm.

The linear intervals between the tips of the teeth and the bases thereof cover approximately less than 60% of the height of the teeth (24), preferably less than 30% of the height of the teeth. In a special embodiment, the profile of the teeth is formed of two round zones without significant intermediate linear range.

In another preferred embodiment, double of the sum of the radii of curvature of the tips of the teeth and the profile between the tips of the teeth represents more than 75% of the separation between adjacent cutting teeth.

Figure 3 shows the side profile of a cutting blade according to the invention. The thickness of the material of the cutting blade at its base (31) is approximately between 0.1 and 1.6 mm, preferably between 0.2 and 0.9 mm, and so Especially preferred between 0.3 to 0.5 mm. The cutting blade is preferably inclines at an angle (32) of approximately 20 ° to 70º, and especially preferably between 35º and 60º in the tensile direction of the adhesive film (42).

An essential aid in the penetration of the leaf metallic in the adhesive film is the narrowing optional material, preferably over the entire width of the blade, at the upper end of the blade. The narrowing of material has its own height (34) of 0.05 - 1 mm, preferably 0.1-0.5 mm and especially preferably 0.2-0.4 mm, the thickness of the material (35) being at the end of approximately 0.1 mm. The narrowing of the material is maintained, for example, as burrs during the stamping process.

The cutting blade is constructed in such a way in the cutting device that the inclined face is in the feed direction of the strip of adhesive tape to be separated.

Figure 4 shows the angle of incidence (43) of the blade (41) in the direction of the strip of adhesive tape (42) a cut. The angle of incidence is advantageously 30º - 110º, preferably 45º - 100º, and especially preferably from 60º - 90º. A small angle of incidence results in general, a characteristic wavy cutting edge, and an angle of incidence close to 90º produces an almost straight cutting edge, only slightly wavy, in the adhesive film.

Through the cutting devices represented in figure 1 films can be cut excellently self-adhesive, for example with, oriented polypropylene brackets biaxially, oriented polyethylene terephthalate supports biaxially, cellulose acetate supports, sheet supports transparent cellulosic, or PVC brackets, to name just Some. Usually, cutting edges are obtained between smooth and wavy with no irregularities or irregularities Minimal microscopic extension in the form of edge cuts sharp or torn in the longitudinal direction of the strips of Adhesive tape cut whenever the strips of adhesive tape are cut down in a centered position in front of the front of the cutting device, that is, without deviating to the left or to the right, without lateral deviation, that is, inclined to the left or to the right.

It is essential to obtain a separation simple that the self-adhesive film is cut with the material narrowed toothed tips. Therefore, the edge of the blade described in figure 3 should be chosen high enough in the sharp area to completely separate the blades usual self-adhesive with a thickness of approximately 0.02 to 0.07 mm The cutting of the jagged ends is then extended by the contour of the blade such that an edge of smooth to slightly wavy cut along the entire width of the self-adhesive film used. The cutting edge does not experience especially no irregularities or irregularities Minimal microscopic extension, in the form of edge cuts sharp or torn, in the longitudinal direction of the strips of adhesive tape cut, which could tear the film adhesive when taken off.

In the cutting device according to the invention, achieves a reduced risk of injury, despite the high power of cutting of the blade, thanks to the narrowing staggered in two stages of the blade edge. The sharp area that protrudes from the blade can only scratch the skin surface minimally. I know prevents deeper penetration of the teeth into the skin thanks to the relatively obtuse angle (32) of Figure 3.

As material for the blade can be used, for example, galvanized or nickel-plated steel strip capable of die cut, to name just a few materials. Too plastic materials such as polystyrene (PS) or acrylonitrile-butadiene-styrene (ABS) However, in embodiments that employ materials plastics, generally, a duration should be provided significantly smaller of the cutting blade compared to a metal blade

The cutting devices for films self-adhesive according to the invention can be used in a large variety of dispenser types. The right dispenser types include manual and desktop dispensers, in which the box that houses the roll of duct tape is locally separated from the film and cutting device holder, dispensers compact and also transfer dispensers, as they have previously described.

The above-mentioned embodiments must understood as an example.

Test methods Proof of a detachment without tearing of the films applied stickers

In the unwinder 10 strips of adhesive film of a length of approximately 3 cm each. The separation is done by pulling the strips of adhesive film at an angle of approximately 75º towards the front of the cutting device without lateral deviation of the film strips adhesive (forward cut). The test can be performed also with a lateral deviation of the adhesive film (cut inclined). In the latter case, the adhesive film is cut starting from one of its sides. Then the strips are glued of adhesive film obtained by slightly passing the fingers until remove all air bubbles present on plastic plates made of rigid PVC (model: Köuml; madur WA; supplier: Krüuml; ger / Wedel), and is passed 5 times over with a roller compression of 1 kg of weight. PVC plates provided with strips of adhesive film are then stored for 3 days in a heated cabin (T = 23.2ºC; air humidity = 50 ± 10%)

To check its detachment without tears, the Adhesive strips are detached manually from its PVC substrate. For it starts by pulling a corner of the film strips adhesive with the fingernail, and then peels off with Caution up to half its length. By the edge of separation opposite, the strips of adhesive film are detached in the same way. In total, 20 take-off checks are carried out at 10 strips of adhesive film. The tests in which the Strips of masking tape peel off the PVC without tearing through the separate edges.

Proof of the ability to be cut pieces of film adhesive

In the unwinder 10 strips of adhesive film of a length of approximately 3 cm each. The separation is carried out as described in the case of "proof of a detachment without tearing of the films self-adhesive applied. "The strips of adhesive film are they cut without lateral deviation of the same (forward cut). The force necessary for the separation of the filmstrips adhesive are subjectively compared with that used for the Separation of the Tesa table topper 6059. The assessment results

"moderately difficult"

in case the force of separation is subjectively comparable with that necessary for separate a piece of Tesa multifilm in the Tesa coiler of desktop 6059;

"very easy"

in case the force of separation is subjectively comparable with that necessary for separate a piece of Tesa multifilm in a Tesa developer from 6059 desktop with the serrated cutting blade replaced by a blade (blade thickness = 0.3 mm; material: steel; blade beveled perpendicularly on both sides; bevel angle = 10th per side).

Example 1

The existing metal blade is replaced in a Tesa 5003 desktop developer by a blade according to the invention. The measures according to figure 2 are as follows: tooth spacing (23) is 1.25 mm, the height of the teeth (24) is 0.4 mm, the radius of curvature in the edge area between two adjacent tooth tips (21) is 0.4 mm, the radius of curvature in the area of the serrated tips (22) is 0.13 mm. The angle of incidence of the blade with respect to the film (43) according to figure 4 it is 80º. The cutting blade is inclined with An angle of 45º in the exit direction. The height of the burr in the area of the serrated tips (34) it is about 0.3 mm, and the thickness of the material at the end of the burr (35) is approximately 0.1 mm.

The ability to be is checked comparatively cut, the structure of the cutting edge and peeling without tears of the strips of adhesive film attached to the self-adhesive tapes # 1 to # 6 19 mm wide. It results the following properties:

Test // Movie # Support Thickness of the Adhesive paste Contribution of mass support adhesive 1.1 / # 1 BOPP * 28 \ mum Copolymer of 19 g / m2 acrylate 1.2 / # 2 BOPP *, ** 35 \ mum Copolymer of 2. 3 g / m2 acrylate 1.3 / # 3 BOPP * 40 \ mum Copolymer of 2. 3 g / m2 acrylate 1.4 / # 4 CAC * fifty \ mum Copolymer of 25 g / m2 acrylate 1.5 / # 5 BOPP * 35 \ mum Natural rubber 22 g / m2 / resin 1.6 / # 6 PE / EVAc *** 80 \ mum Copolymer of 25 g / m2 acrylate Test // Movie # Can be cut toward Cutting edge Taken off without tears front // laterally 1.1 / # 1 Easy // very easy Slightly curly > 90% 1.2 / # 2 Easy // very easy Slightly curly > 90% 1.3 / # 3 Easy // very easy Slightly curly > 90% 1.4 / # 4 Easy // very easy Slightly curly Do not checked 1.5 / # 5 Easy // Very easy Slightly wavy > 90% 1.6 / # 6 Easy // easy Slightly curly > 100% * BOPP = biaxially oriented polypropylene; CAC = acetate cellulose ** corresponding to multifilm Tesa *** PE / EVAc-sheet PO 01612 / 6807.0010: supplier: Renolit

In all cases they occur, in the use of cutting device according to the invention, cutting edges slightly wavy All adhesive films can be separated both in the cut forward as in the inclined cut easily or very easy, and the calendered sheet on a mixture basis of PE and EVAc copolymer easily. Virtually all strips Adhesives can peel off after sticking without tears. For set the comparison, adhesive films # 1 to # 3 are treated with a Tesa 5003 developer equipped with an original blade. The separation is valued in all cases as easy, in the cut inclined, and as moderately easy in the centered cut. The peeled without tearing the strips of glued adhesive film only possible in approximately 10% to 30% of all cases.

Example 2

In a manual Tesa 5003 developer modified analogously to example 1, the height of the tips of the blade along the support surface (12) of figure 1. The ability to be is checked comparatively cut, the structure of the cutting edge and peeling without Tears of the adhesive film strips attached to the multifilm Tesa (= adhesive film # 2 of example 1). The separation between the cutting blade (14) and the support surface of the film (12) is 0.5 mm. This results in the following properties:

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Test Blade Height a the Ability to be cut Edge of cut Taken off without along the support surface toward front / side tears 2.1 0 mm Easy // Very easy Slightly > 80% curly 2.2 0.5 mm Easy // Very easy Slightly > 90% curly 2.3 1.0 mm Easy // Very easy Slightly > 80% curly 2.4 1.5 mm Easy // Very easy Slightly > 80% curly 2.5 2.0 mm Easy // Very easy Slightly > 70% curly

As a result of the separation distance between the cutting blade (14) and the support surface of the film (12), the blade may be in the same plane as the blade holder, that is, the height of the blade at length of the film's support surface is 0 mm. In the In this case, the tips of the blade should not protrude more than 1 mm above the support surface of the film, since in otherwise there is no sure support from the film about the support surface of it. The detachment without tears of the Self-adhesive film improves significantly in all cases in the present example compared to the original blade of the Tesa 5003 manual dispenser (see example 1).

Example 3

A manual Tesa 5003 reel is supplied with a cutting blade according to the invention, analogously to the Example 1. The bevel position (32) of the cutting blade (see figure 3). The beveled part of the blade it is checked in the direction of traction and in the opposite direction to the advance of the strip of adhesive tape to be cut. It is checked comparatively the ability to be cut, the structure of the cutting edge and tear-off of the strips of film adhesive adhesive for the Tesa multifilm (= adhesive film # 2 from example 1). This results in the following properties:

Test Bevel of die cut Ability to be cut Edge of cut Taken off toward front / side no tears 3.1 In the direction of Advance Easy // Very easy Slightly > 80% from the adhesive tape to cut curly 3.2 In the opposite direction to Advance Easy // very easy Slightly Approx. fifty% from the adhesive tape to cut curly

In all test devices it is observed an ability to be cut from the adhesive film used of very easy shape with a slightly resulting cutting edge curly. In more than 80% of cases in which the orientation of the Beveling (32) of the cutting blade is in the forward direction from the adhesive film to be cut the adhesive tape can peel off no tears If, on the other hand, the blade with the bevel is arranged in the opposite direction to the advance of the adhesive film, the same it tears with a significantly higher frequency. As a cause it is presumed very fine microscopic cuts in the direction longitudinal to the adhesive film. However, it follows obtaining a significant improvement compared to the blade Tesa 5003 manual Unwinder original.

Example 4

A manual unwinder from Tesa 5003 is provided modified analogously to example 1 with different blades of cut. The serrated blades correspond to those of example 1. varies the angle of incidence of the cutting blade with respect to to the strips of adhesive film to be cut. It is checked comparatively the ability to be cut, the structure of the cutting edge and tear-off of the strips of film adhesive adhesive for the Tesa multifilm (= adhesive film # 2 from example 1). This results in the following properties:

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Test Angle of incidence of the knife Ability to be cut Edge of cut Taken off without With respect to movie plane toward front / side tears 4.1 80º Easy // Very easy Slightly > 80% curly 4.2 60º Easy // Very easy Moderately > 80% curly 4.3 45º Easy // Very easy Slightly > 80% curly 4.4 30th Easy // Very easy Slightly > 80% curly

For all angles of incidence you get an ability to cut the tape easily. The breadth of the undulation that occurs in the cutting of the blade increases to as the angle of incidence of the blade decreases. The Profile of the cut is clear in all cases, without observing damage in the longitudinal direction. All samples can peel off without tears in at least 80% of cases.

Example 5

Takeoff is checked without tearing of the Tesa multifilm for different commercial dispensers in comparison with a Tesa 0503 manual dispenser equipped with cutting blades according to the invention.

Test Dispenser Thickness Angle from Separation Height Separation Shape of the from the incidence between from the between knife knife from the teeth teeth teeth/ (schematic) [mm] knife [mm] [mm] Height from [º] the teeth 5.1 Overwhelming Handbook 0.5 54 one 1.3 0.8 from Tesa 5653/5003 5.2 Overwhelming Handbook 0.4 Four. Five one 0.9 1.1 from Tesa 5846 5.3 Overwhelming Tesa 0.4 Four. Five one 0.7 1.4 from desktop 6059 5.4 Overwhelming Tesa 0.6 85 1.3 0.7 1.9 from desktop 56210 5.5 Overwhelming 0.6 Four. Five 1.5 1.4 1.1 Eurecel Handbook 5.6 Overwhelming Handbook 0.4 80 one 0.9 1.1 from 3M HE 100 5.7 Overwhelming 3M 0.5 Four. Five 0.9 0.7 1.3 from HE desktop 200 5.8a Overwhelming from 0.5 70 1.3 0.4 3.3 5.8b Tesa from desktop 0.5 70 1.0 0.3 3.3 5.8c 5003 modified 0.4 70 2.0 0.7 2.9 with the devices from cut a, b, c according the invention

Test TO B [mm] C [mm] D E [º] F G (%) 5.1 Its T 0.07 0.10 Yes 90 Moderately hard 6 5.2 Its T 0.05 - Yes 80 Moderately hard 6 5.3 Its T 0.14 0.16 Yes 90 Moderately hard 19 5.4 Bis 0.03 0.3 Yes 30 Easy // easy very 44 5.5 Its T 0.19 0.19 Yes 90 Moderately hard 13 5.6 Its T 0.14 0.11 Yes 90 Moderately hard 25 5.7 Its T 0.05 0.08 Yes 30 Moderately hard 25 5.8a Its T 0.13 0.4 Do not Four. Five Easy // Very easy \ geq90 5.8b Its T 0.13 0.3 Do not Four. Five \ geq90 5.8c Its T 0.13 0.7 Do not Four. Five \ geq90 Legend for columns: A \ hskip0,5cm stamped blade (est) / beveled (bis) B \ hskip0,5cm radius of curvature of the blade tips C \ hskip0,5cm radius of curvature in the profile area between toothed tips D \ hskip0,5cm linear zone of cutting between jagged tips and tooth bases E \ hskip0,5cm angle of die cut F \ hskip0,5cm ability to be cut l tape forward // laterally G \ hskip0,5cm ability to take off without tears

The dispenser blades with an angle of die cut close to 90º (tests 5.1, 5.2, 5.3, 5.5 and 5.6) present in all cases reduced values in terms of their ability to peel off the adhesive tape without tears. The profiles obtained cutting are typically very irregular, and the forces necessary for high cutting. In no case is the Shape of the cutting blade sharply on the film Adhesive cut, not obtaining a sharp cut profile. In in many cases the adhesive film is torn irregularly already during cutting, and no adhesive film strips are obtained rectangular It can be presumed that microscopic cuts in Longitudinal direction of the strips of adhesive tape cut are the cause of unsatisfactory results in the resumption without waste. The overwhelming 3M desktop HE 200, with an angle of 30 ° die cut, also provides reduced values for resumption without waste, mainly caused by reduced radii of curvature in the area of the toothed tips of the cutting blade, as well as in the profile area between contiguous cutting teeth. The Tesa desktop sweeper 56210, with values of more than 40% take off without tearing, found significantly above the dispensers described above (test 5.4) thanks to the reduced radii of curvature in the contour area between adjacent jagged points as well as at its reduced die cut angle. It turns out however disadvantageous the high cutting power of the serrated tips that gives for a reduced radius of curvature of only 0.03 mm. In this case, the high cutting power of the teeth, which is prolonged even along the edges of them, it causes cuts in the direction of the strips of cut adhesive film that make fail, as the test shows, the detachment of the strips of adhesive film of its substrate in one piece. It also turns out disadvantageous the linear (straight) path of the blade profile in the intermediate zone between jagged points and bases of the teeth.

The blades according to the invention (tests 5.8a, b, c) present in all cases

? a die angle of << 90º,

high values for the relationship separation between teeth / height of teeth,

a round profile of the cutting edge with

?

radios of moderate curvature in the area of the jagged tips,

?

radios of reduced curvature in the profile area between cutting teeth contiguous,

as well as for the integration of a narrowing of the material in the area of the jagged tips an ability to be easily or very easily cut from the Tesa multifilm. The cuts obtained in the strips of adhesive tape to be cut by teeth contiguous cutting extend on the contour of the cutting edge of so that they approximately penetrate each other, so that produces no tear, or virtually none, in the direction length of strips of adhesive tape cut, being able to subsequently peel off the pieces of adhesive tape from its substrate without tears

Claims (13)

1. Dispenser blade (41) for an adhesive tape dispenser, especially formed by a box, a roller core housing and an adhesive tape holder (12) disposed in front of the dispenser blade (41), the provided Dispenser blade (41) of a cutting edge (14), characterized in that the cutting edge (14) has a wavy shape with cutting teeth (24) convexly rounded with respect to the adhesive film support (12) and concavely rounded areas between teeth contiguous cutting (24), with linear areas between serrated tips (22) and tooth bases (21), representing the linear areas between serrated tips (22) and tooth bases (21) less than 60% of the height of the teeth (24), preferably less than 30% of the height of the teeth (24), the serrated tips and the bases of the teeth being arranged in the same plane, so that the cuts produced in the strips of adhesive tape (42) to be cut by di contiguous entities (24) extend along the edge of the cutting edge (14), so that they extend approximately one inside the other, so that no tearing occurs, or practically none, in the longitudinal direction of the strips of cut adhesive tape (42) and the pieces of adhesive tape (42) can be subsequently detached from its substrate without tears. 2. Dispenser blade (41) according to claim 1, characterized in that no linear area is provided between the serrated tips (22) and the bases of the tips (21). 3. Dispenser blade (41) according to claims 1 and 2, characterized in that the dispenser blade (41) is arranged in relation to the support surface (12) such that the serrated tips (22) are positioned 2 mm below 3 mm above it, preferably 0.3 to 1 mm above it, and / or the separation between the dispenser blade (41) and the support surface (12) is 0 , 1 mm to 5 mm, preferably 0.2 mm to 2 mm, and especially preferably 0.3 mm to 1 mm. 4. Dispenser blade (41) according to claims 1 to 3, characterized in that the dispenser blade (41) has an angle of incidence (43) in the direction of the strip of adhesive film (42) to be cut between 30 ° and 110º, preferably between 45º and 100º, and especially preferably from 60º to 90º. 5. Dispenser blade (41) according to claims 1 to 4, characterized in that the dispenser blade (41) has at its base a thickness of material comprised between 0.1 mm and 1.6 mm, preferably between
0.2 mm and 0.9 mm, and especially preferably between 0.3 mm and 0.5 mm, because it is inclined in the direction of advancement of the adhesive film (42) at an angle between 20 ° and 70 °, preferably between 35 ° and 60 °, and because it has a narrowing of the material especially along the entire width of the cutting edge at its upper end. 6. Dispenser blade (41) according to claim 5, characterized in that the narrowing of the material has its own height between 0.05 mm and 1 mm, preferably between 0.1 mm and 0.5 mm, and of especially preferred between 0.2 mm and 0.4 mm, the thickness of material at the end being 0.1 mm. 7. Dispenser blade (41) according to claims 1 to 6, characterized in that the separation between adjacent toothed tips (22) is between 0.3 mm and 4 mm, preferably between 0.5 mm and 3 mm, and especially preferably between 1 mm and 1.5 mm. 8. Dispenser blade (41) according to claims 1 to 7, characterized in that twice the sum of the radii of curvature of the serrated tips (22) and the profile between the serrated tips (22) represents more than 75% of the separation between adjacent jagged tips (22). 9. Dispenser blade (41) according to claims 1 to 8, characterized in that the height of the teeth (24), measured between the concavely rounded area between adjacent cutting teeth (24) and the serrated tips (22), represents especially preferably less than half the separation distance between adjacent toothed tips (22). 10. Dispenser blade (41) according to claims 1 to 9, characterized in that the height of the teeth (24), measured between the concavely rounded area between adjacent cutting teeth (24) and the serrated tips (22), is between 0.15 mm and 2 mm, preferably between 0.2 mm and 1.5 mm, and especially preferably between 0.3 mm and 0.7 mm. 11. Dispenser blade (41) according to claims 1 to 10, characterized in that the radius of curvature of the serrated tips (22) is between 0.05 mm and 0.7 mm, preferably between 0.07 mm and 0.4 mm, and especially preferably between 0.1 mm and 0.25 mm, and / or the radius of curvature of the edge between the serrated tips (22) has values between 0.1 mm and 2 mm, preferably between 0.15 mm and 1.4 mm, and especially preferably between 0.25 mm and 0.7 mm. 12. Dispenser blade (41) according to claims 1 to 11, characterized in that the dispenser blade (41) has a pattern burr on the serrated edge, especially on the serrated tips (22).

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13. Dispenser blade (41) according to claims 1 to 11, characterized in that the edge of the dispenser blade (41) has a regular shape.