Supply roll with a sealing strip

Abstract

A supply roll is described comprising a sealing tape (5) made of an open-pore soft foam (1) and a winding core (4) for the coils of the pre-compressed sealing tape (5), which is provided on one side with a self-adhesive layer (2) and bears against each other under radial pressure. To advantageously create functional conditions, it is proposed that the self-adhesive layer (2) be covered with a self-adhesive adhesive layer (3) and that the adhesive forces between the self-adhesive layer (2) and the self-adhesive adhesive layer (3) be lower than the adhesive forces between the adhesive layer (3) and the soft foam (1) of the sealing tape (5).

Description

[0001] The invention relates to a supply roll with a sealing tape made of an open-pore soft foam and with a winding core for the windings of the pre-compressed sealing tape, which is provided with a self-adhesive layer on one side and which lie against each other under a radial pressure load.

[0002] To prevent the self-adhesive layer on one side of the sealing tape from sticking the adjacent coils of the roll together, it is known (EP 2 851 478 A1) to provide a cover layer on the side of the sealing tape opposite the self-adhesive layer. The adhesive force between the cover layer and the self-adhesive layer is less than the adhesive force between the cover layer and the soft foam, so that when the sealing tape is pulled from the roll, the cover layer detaches from the self-adhesive layer. This additional cover layer of the sealing tape has the advantage of ease of handling compared to a protective cover that can be peeled off the self-adhesive layer, because it eliminates the need to remove the protective cover from the self-adhesive layer before using the sealing tape.However, a disadvantage is that this covering layer jeopardizes the tight seal of the sealing tape inserted into a construction joint against the rough joint wall in the area of ​​the covering layer, due to the stiffening of the surface of the sealing tape caused by the covering layer.

[0003] To ensure a tight seal of the sealing tape against the joint wall on the side of the tape opposite the self-adhesive layer, it has already been proposed (EP 3 323 969 A1) to form the cover layer in a mesh-like structure. This would allow the soft foam, which passes through the mesh openings, to expand as the pores of the pre-compressed sealing tape fill with air, thus significantly determining the seal's contact with the joint wall. However, such mesh-like cover layers, as well as other cover layers on the side of the sealing tape opposite the self-adhesive layer, involve additional effort.

[0004] To overcome the difficulties associated with providing a self-adhesive layer on one side of a sealing tape wound into a supply roll, it is also known (EP 3 179 003 A1) to provide a double-sided adhesive tape on one side of the foam layer of the sealing tape. This double-sided adhesive tape comprises a carrier strip and two adhesive coatings on opposite sides of the tape. Since the adhesive force between the double-sided adhesive tape and the foam layer ensures a permanent bond, the lower adhesive force of the outer adhesive coating allows the double-sided adhesive tape to be detached from the coils of the foam layer in the area of ​​a supply roll. This allows the sealing tape to be peeled off the supply roll without the need for a separate cover layer for the double-sided adhesive tape.However, this advantage comes at the cost of the additional effort required by the double-sided adhesive tape, which is primarily due to the additional carrier tape required for the two adhesive coatings, making it more difficult to seal the sealing tape properly in a construction joint.

[0005] The invention is therefore based on the objective of designing a supply roll of sealing tape in such a way that, under the condition of comparatively simple manufacturing conditions, a sealing tape is provided that is easy to handle and also meets higher requirements for the sealing of construction joints.

[0006] Starting from a supply roll of the type described above, the invention solves the problem by covering the self-adhesive layer with a self-adhesive adhesive layer and by ensuring that the adhesive forces between the self-adhesive layer and the self-adhesive adhesive layer are lower than the adhesive forces between the adhesive layer and the soft foam of the sealing tape.

[0007] The adhesive layer covering the self-adhesive layer prevents the side of the sealing tape opposite the self-adhesive layer from coming into contact with the self-adhesive layer of the adjacent windings when the sealing tape is wound onto a core. This eliminates the need for an additional cover layer on the side of the sealing tape opposite the self-adhesive layer, as well as a protective cover that needs to be peeled off the self-adhesive layer before using the sealing tape.Due to the differing adhesion properties of the self-adhesive layer on the one hand, and the adhesive layer on the other, on the other hand, the adhesive layer detaches from the adhesive layer when the sealing tape is pulled from the roll. It then adheres, at least in large part, to the side of the foam opposite the adhesive layer, meaning the sealing tape simply needs to be peeled from the roll before use. The adhesive strength of the self-adhesive layer ensures that the sealing tape, firmly bonded to the joint, adheres to the opposite wall even when it expands elastically back towards its unloaded position. This reinforces the seal between the tape and the joint, even if the adhesive strength of the layer is low.

[0008] Since the adhesive layer has the task of preventing the foam side of the windings of the sealing tape from sticking to the self-adhesive layer within the pre-roll, by providing this adhesive layer between the self-adhesive layer and the soft foam of the adjacent winding of the sealing tape, the adhesive layer can have different structures.

[0009] The only important thing is that the adhesive layer forms a separating layer that prevents the self-adhesive layer from sticking to the adjacent foam side of the sealing tape, which adheres to both the self-adhesive layer and the soft foam of the sealing tape within the supply roll, but detaches from the self-adhesive layer when the sealing tape is pulled from the supply roll due to its adhesive properties.

[0010] The supply roll is typically encased in a tensile-resistant sleeve to prevent the sealing tape from expanding elastically by filling the pores with air and detaching from the core. To prevent the sealing tape from unintentionally unwinding from the supply roll once the sleeve is removed, it is known to design the cover layer on the side of the sealing tape opposite the self-adhesive layer to be tensile-resistant. Such a cover layer, which adheres firmly to the self-adhesive layer of the subsequent turn in the area of ​​each individual turn, prevents the turns from shifting circumferentially and thus prevents the sealing tape from expanding in the area of ​​the adjacent turns. To achieve a comparable effect without an additional cover layer, the self-adhesive layer can be designed to be tensile-resistant in the longitudinal direction of the sealing tape, for example, by means of appropriate reinforcement.

[0011] Particularly advantageous functional conditions arise when the self-adhesive layer is designed as a thin film and, upon pressure release of the pre-compressed sealing tape, can be partially drawn into the pores of the foam surface. In this case, structural conditions can be created on the surface of the sealing tape opposite the self-adhesive layer that are comparable to an uncovered foam surface. This results in particularly good conditions for the sealing tape to adhere tightly to rough, uneven joint walls due to the elastic expansion of the soft foam and the drawing of air into the foam pores.

[0012] The invention is illustrated in the drawing as an example. It shows Fig. 1 shows a sealing membrane for a supply roll according to the invention before its winding onto a winding core in a schematic longitudinal section and Fig. 2 shows a supply roll according to the invention in a schematic side view.

[0013] The conventional method for producing a stock roll starts with a web of open-pore soft foam, which, after appropriate pretreatment and coating, is wound onto a winding body under tensile stress and compressed before the web roll is divided into individual stock rolls. Fig 1 The diagram illustrates the structure of a web made of open-pored soft foam, which is advantageous for the production of a supply roll according to the invention, in a longitudinal section.

[0014] The open-pored soft foam 1, which is preferably impregnated in a known manner to delay its return to an unloaded initial position after compression, has a self-adhesive layer 2 on one side, which is covered by a self-adhesive layer 3. The adhesive strength of this adhesive layer 3, which is preferably designed as a thin layer, is lower than that of the soft foam 1.

[0015] If such a sheet of soft foam 1 is wound onto a winding body under appropriate force and then axially divided, supply rolls according to the invention are obtained. As is immediately apparent, the same result is achieved, albeit with considerably more effort, if the adhesive layer 3 is not applied to the self-adhesive layer 2, but rather the sheet of soft foam 1 is provided with the adhesive layer 3 on the side opposite the self-adhesive layer 2, so that when such a sealing sheet is wound, the adhesive layer 3 again lies between the self-adhesive layer 2 and the soft foam 1 of the adjacent turns and thus covers the self-adhesive layer opposite the adjacent turn.

[0016] Regardless of the possible manufacturing methods, storage rolls according to the invention exhibit the following properties: Fig. 2 A winding core 4 is wound onto which the sealing tape 5 is pre-compressed under radial pressure in a corresponding number of turns. The side of the sealing tape 5 with the self-adhesive layer 2 rests against the foam side of the sealing tape 5 of the adjacent turn in the area of ​​the turns of the sealing tape roll, with the adhesive layer 3 interposed. Due to the adhesion conditions, greater adhesive forces arise between the self-adhesive layer 3 and the foam surface of the adjacent turn of the sealing tape 5 than between the adhesive layer 3 and the self-adhesive layer 2, which is permanently bonded to the soft foam 1. This results in the adhesive layer 3 detaching from the self-adhesive layer 2 and adhering to the surface of the soft foam 1 when the sealing tape 5 is pulled from the supply roll, as described in the Fig. 2The figure shows a supply roll with a sealing tape 5 partially peeled from the supply roll, which, after being peeled from the supply roll, expands with a corresponding delay by filling the pores of the pre-compressed soft foam 1 with air during elastic return to the unloaded starting position and has the self-adhesive layer 2 on one side and the adhesive layer 3 on the opposite side.

[0017] The sealing tape 5, which has been peeled from the supply roll and is at least partially compressed, can therefore be easily inserted into a construction joint and pressed against a joint wall with the self-adhesive layer 2, before, after an elastic expansion, it adheres to the opposite joint wall with the self-adhesive adhesive layer 3 and bonds to the joint wall via this adhesive layer.

[0018] Since the uncoated side of the soft foam 1 of the sealing tape 5 rests against the self-adhesive layer 3 of the coated side of the sealing tape 5 between the coils of the sealing tape roll under adhesion conditions that preclude any circumferential displacement of the coils, the pre-compressed sealing tape 5 can be held within the supply roll under radial compressive stress. This stress counteracts any elastic, expanding return of the sealing tape 5 when longitudinal elongation of the sealing tape 5 is prevented. For this purpose, the self-adhesive layer 2 can be made tensile-resistant in the longitudinal direction of the sealing tape 5, for example, by fiber reinforcement. The sealing tape 5 can then be pulled off the required length from the supply roll without subjecting the remaining sealing tape 5 on the supply roll to any risk of expansion.

Claims

1. Supply roll with a sealing tape (5) made of an open-pore soft foam (1) and with a winding core (4) for the windings of the pre-compressed sealing tape (5) which is provided on one side with a self-adhesive layer (2) and which are in contact with each other under a radial pressure load, characterized by the fact that the self-adhesive layer (2) is covered with a self-adhesive adhesive layer (3) and that the adhesive forces between the self-adhesive layer (2) and the self-adhesive adhesive layer (3) are less than the adhesive forces between the adhesive layer (3) and the soft foam (1) of the sealing tape (5).

2. Supply roll according to claim 1, characterized by the fact that the self-adhesive layer (2) is designed to be tensile-resistant in the longitudinal direction of the sealing tape (5).

3. Supply roll according to claim 1 or 2, characterized by the fact thatthe self-adhesive adhesive layer (3) is designed as a thin layer and can be partially absorbed into the pores of the foam surface when the pressure of the pre-compressed sealing tape (5) is released.

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