Process for producing a carrier material for textile adhesive tapes, carrier material and use

Abstract

Method for producing a carrier material for textile adhesive tapes, in which in a stitch-bonding machine - a fleece or nonwoven fabric is fed in, on which a standing thread layer and a weft thread layer are laid, - a pile thread layer is formed and - the arrangement of nonwoven or nonwoven fabric, standing threads and weft threads in the working direction of the stitch-bonding machine is over-sewn with sewing threads, while simultaneously incorporating the pile threads.

Description

[0001] The invention relates to a textile coating carrier that is particularly suitable for further processing into an adhesive tape, i.e., a textile carrier material for adhesive tapes with high noise damping. This adhesive tape is preferably used for sheathing elongated cable harnesses and lines.

[0002] These adhesive tapes are used, for example, in the automotive industry in the production of cable harnesses. Their functions include bundling the individual wires and preventing or dampening rattling noises. With the increasing number of electric vehicle approvals in the future, the demands on adhesive tapes for cable harnesses are becoming increasingly stringent. The extremely quiet vehicles of the future pose additional new challenges. The key requirements are weight reduction, high noise dampening properties, as well as good processability and strength in the longitudinal and transverse directions.

[0003] The following application-related requirements apply to coating substrates for such adhesive tapes: - High force absorption in the longitudinal direction with low deformation (elongation). - High longitudinal and transverse strength with the lowest possible weight. - Low resilience to prevent the adhesive tapes from detaching from the cable harness. - Easy hand tear in the transverse direction. - High abrasion resistance. - Fiber pull-out resistance. This means that the fibers must be so tightly integrated into the nonwoven surface that they do not stick to the adhesive on the top layer when unrolled from the tape roll. - High noise reduction.

[0004] Noise reduction is determined through comparative measurements according to the automotive supplier standard LV 312. Adhesive tapes are therefore classified into different noise reduction classes: A no noise reduction 0 to 2 dB(A) B low noise attenuation >2 to 5 dB(A) C average noise attenuation >5 to 10 dB(A) D high noise attenuation >10 to 15 dB(A) E very high noise attenuation >15 dB(A)

[0005] To achieve good noise reduction values, nonwovens are typically used as a component of the coating backing. The noise reduction properties of the adhesive tapes improve with increasing nonwoven thickness or basis weight. However, with increasing basis weight, hand tearability and resilience deteriorate. Furthermore, material costs rise, which is why simply increasing the basis weight is not a viable approach to producing adhesive tapes with high noise reduction.

[0006] Textile adhesive tapes based on stitch-bonded nonwovens are described, for example, in DE 94 01 037 U1 and EP 0 668 336 A1. The coating backings are manufactured on Maliwatt machines by overstitching the nonwovens with numerous parallel seams. This construction can only achieve moderate noise reduction at best, because the high basis weight of the nonwovens conflicts with the requirements for transverse tear resistance of the adhesive tapes and low resilience, as well as with cost constraints.

[0007] Using Kunit or Multiknit technology, voluminous close-knit nonwovens with a vertical fiber pile and fiber mesh surfaces on one or both sides can be produced. These coating backings for adhesive tapes, described in DE 44 42 507 A1, exhibit high noise dampening due to their voluminous nature. However, their very low transverse strength and high deformation under tensile stress are disadvantages. Under tensile stress, the width of the adhesive tapes decreases, and the edges buckle. This is unacceptable in practice.

[0008] DE 44 42 093 A1 describes an adhesive tape based on Malivlies. These adhesive tapes also exhibit good sound-damping properties. However, in the stitch-bonded nonwoven Malivlies, only very few fibers are integrated into the fiber mesh, so the resulting adhesive tapes have little resistance to fiber tearing. When unwinding the adhesive tape roll, fibers from the front of the underlying layer are pulled out of the composite and adhere to the adhesive, severely limiting the adhesive strength of the adhesive tape. Further disadvantages of Malivlies adhesive tapes include the high deformation under tensile stress, with the effects already described.

[0009] DE 10 2007 030 567 B3 describes a pressure-elastic textile backing with high noise dampening properties. This product consists of a textile fabric with pile loops sewn into it on a stitch-bonding machine. The textile fabric is preferably a mechanically, chemically, or thermally bonded fiber or filament nonwoven, which is responsible for the strength and elongation properties of the adhesive tape. This nonwoven is presented to the stitch-bonding machine in prefabricated form. The pile folds, consisting of filament yarns, textured yarns, or fiber yarns, provide pressure elasticity and good noise dampening. By using yarns as the pile layer, a significant improvement in fiber tear-out from the adhesive tape surface can be achieved compared to coating backings with fiber pile.

[0010] However, it has been shown that the numerous needle punctures during the incorporation of the pile pleats can severely damage or even destroy the nonwoven fabric, rendering it unable to meet its intended strength and elongation properties in the adhesive tape. The more or less pronounced "needling" of the nonwoven fabric significantly reduces the tensile strength of the coating carriers and increases deformability (longitudinal stretch) to an unacceptable extent, thus calling into question the stability of the entire construction.

[0011] Adhesive tapes made from pre-consolidated nonwovens, such as spunbonded nonwovens, have the disadvantage of high elongation at break. Stretching of the adhesive tape made from these non-reinforced nonwovens leads to warping and curling of the edges during processing. (DE 101 21 109 A1 or DE 298 04 431 U1)

[0012] EP 2 128 212 A2 describes an adhesive tape made of pre-consolidated nonwovens, which is stabilized in its longitudinal direction by overstitching. Here, carrier materials in the weight classes between 30 and 120 g / m 2 Due to the nature of pre-bonded nonwovens, such as spunbond, high levels of noise dampening can only be achieved by significantly increasing the weight of the nonwoven. Spunbond material, in particular, loses its textile character due to the increase in mass and becomes very stiff with increasing weight. This significantly reduces hand tearability and conformability, making it unsuitable for certain applications.

[0013] Furthermore, DE 103 37 565 B4 discloses a textile covering element as a protective sheath for cables, brake hoses, cable pulls or the like made of a nonwoven fabric reinforced by thread stitches, wherein the thread stitches are formed by one or two knitting thread systems with different weaves, whereby the nonwoven fabric has a high tendency to curl when cut in a band-like manner in the longitudinal or transverse direction to the textile covering element transversely to the longitudinal axis of the latter.

[0014] US 4,841,749 A describes the production of aesthetic fabrics with warp and weft insertion consisting of multiple substrate layers, with the warp threads extending in the warp direction of the fabric and the weft threads in the weft direction of the fabric. The warp and / or weft threads are inserted between the multiple substrate layers. Warp and weft threads, spaced along the warp direction of the fabric and sewn through the substrate layers, hold the warp and weft threads in position relative to each other and to the substrates. The substrates can also be arranged side by side to increase the opacity, aesthetics, and dimensional stability of the fabric. Thermoplastic fibers can be incorporated into the fabric to assist in the bonding of the resulting fabric after plasticization and subsequent cooling.

[0015] DE 20 2010 006 413 U1 relates to a nonwoven composite as a textile carrier for adhesive tapes, consisting of a voluminous nonwoven and a thin nonwoven or nonwoven fabric, connected by fiber balls, fiber meshes or fiber plugs introduced from the nonwoven or nonwoven fabric into the voluminous nonwoven.

[0016] Finally, DE 10 2010 038 622 A1 describes a method for producing a belt for a machine for producing web material, in particular press felt, comprising the measures: A) providing a first fiber material layer as a nonwoven stitch-bonded layer, B) providing at least one further layer, C) positioning the first fiber material layer and the at least one further layer on top of each other, D) connecting the first fiber material layer to the at least one further layer.

[0017] With regard to good sound-damping properties, there are numerous textile backings that specifically improve this important property using a pile system. For example, WO 99 / 50943 A1 describes a pile surface made of knitted velour. The production of surfaces from pure thread systems without the use of nonwovens, such as velour, results in very cost-intensive products.

[0018] The invention is therefore based on the object of developing a reinforced nonwoven composite which can be produced with little effort, which has easily adjustable transverse and longitudinal strengths and whose level of noise damping properties can be easily adapted.

[0019] To solve this problem, a nonwoven fabric consisting of one or more layers and / or a pre-consolidated nonwoven fabric made of fibers and / or filaments is combined with a construction consisting of sewing thread, weft thread, standing thread, and pile thread. In other words, when incorporating pile loops into the pre-consolidated nonwoven fabric, for example, additional threads arranged transversely or diagonally to the working direction, as well as in the working direction (longitudinal direction), are applied to the nonwoven fabric. These threads are connected to the nonwoven fabric with an additional sewing thread system that is functionally different from the pile threads.

[0020] A method for producing a carrier material for textile adhesive tapes is proposed, in which in a stitch-bonding machine • a fleece or nonwoven fabric is fed in, • a standing thread layer and a weft thread layer are laid on the fleece or nonwoven fabric, • a pile thread layer is formed and • the arrangement of fleece or nonwoven fabric, standing threads and weft threads in the working direction of the stitch-bonding machine is sewn over with sewing threads, with the pile threads being incorporated at the same time.

[0021] The individual components such as nonwoven fabric, weft thread, standing thread and pile thread can be replaced easily, quickly and without any modifications to the systems and can therefore be precisely adapted to the requirements regarding longitudinal strength (standing thread), transverse strength (weft thread) and noise dampening (pile thread) of the textile carrier.

[0022] The density of the stitching threads in the backing material can be significantly reduced, as the stay thread improves the strength in the longitudinal direction. A reduction in the number of stitching threads (thread consumption 1 to 3.5 or greater) is made possible by using a stay thread (thread consumption 1 to 1.1). The weft thread is used for transverse stabilization and counteracts damage to the backing web with regard to transverse strength. The pile threads are thus firmly incorporated into the construction of the aforementioned thread systems and the backing web and remain firmly in the backing material during subsequent processes and in the final application.

[0023] Sewing threads and pile threads can be made of the same or, preferably, different thread materials. The standing threads and weft threads are not damaged during the incorporation of the pile loops and thus stabilize the fabric by absorbing forces in the longitudinal and transverse directions to the required extent. The damaged nonwoven layer thus largely relinquishes its function as a reinforcement to the weft and sewing threads, as assigned in DE 10 2007 030 567 B3, and serves only as a surface for the adhesive. The type of thread material and thread density can be easily adapted to requirements.

[0024] In a first embodiment of the proposed process, the pile threads are incorporated directly into the nonwoven fabric to form the pile thread layer.

[0025] In a second embodiment of the proposed method, the pile threads are sewn over with the sewing threads together with the standing thread layer and the weft thread layer to form the pile thread layer and are bonded to the nonwoven or nonwoven fabric.

[0026] For example, the pile thread layer can be applied to a first side of the nonwoven fabric and the standing thread layer and the weft thread layer can be laid on a second side of the nonwoven fabric opposite the first side and fastened with the sewing threads.

[0027] In the proposed method, it can be provided that the nonwoven fabric used is a prefabricated calendered spunbonded polyester fabric with a basis weight of 15 to 80 g / m 2 , preferably 40 g / m2 is used.

[0028] Alternatively or additionally, it can be provided that PES yarns with a fineness of 3.3 to 16.7 tex, preferably 9 tex, are used as standing threads and / or as weft threads.

[0029] In the same way, alternatively or additionally, it can be provided that polyester silk with a fineness of 3 to 7.6 tex, preferably 5 tex, is used as sewing threads.

[0030] In a further embodiment of the proposed method, polyester filament yarns (textured or untextured) with a fineness of 5 to 16.7 tex, preferably 7.6 tex, are used as pile threads, which are guided over a pile plate with a thickness of 0.5 to 5 mm, preferably 2 mm high.

[0031] The proposed method makes it possible to produce a reinforced carrier material for textile adhesive tapes, comprising a multilayer composite construction with at least one nonwoven layer made of a fiber nonwoven and / or filament nonwoven, a standing thread layer, a weft thread layer, and a pile thread layer, and which can advantageously be used to produce a sound-insulating adhesive tape. Furthermore, an adhesive can be applied to the second side of the carrier material, which is opposite the first side on which the pile thread layer is arranged.

[0032] Such an adhesive tape can be used advantageously for sheathing elongated cable harnesses and lines. Example:

[0033] A prefabricated calendered spunbonded polyester fabric with a basis weight of 40 g / m² is fed onto a stitch-bonding machine. 5 tex polyester silk is used as the sewing thread. 7.6 tex polyester filament yarns are used as the pile threads, which are guided over a 2 mm high pile plate. 9 tex PES yarns are used as the weft threads, which are positioned on the nonwoven surface using a lapper and integrated into the sewing thread loops together with the nonwoven.

[0034] The fabric has, for example, the following textile-physical properties: Basis mass: 74 g / m2 Maximum tensile force longitudinal: 81 N / 2 cm Maximum tensile force transverse: 56 N / 2 cm Maximum tensile strength elongation longitudinally: 16% Initial elongation at 40 N / 2 cm: <5% Overhang length: 4.2 cm

[0035] The surface structure coated with hot-melt adhesive has a noise reduction of 10 dB(A) and thus achieves noise reduction class 4.

Claims

[1] Process for producing a carrier material for textile adhesive tapes, in which in a stitch-bonding machine - a fleece or nonwoven fabric is fed in, on which a standing thread layer and a weft thread layer are laid, - a pile thread layer is formed and - the arrangement of nonwoven or nonwoven fabric, standing threads and weft threads in the working direction of the stitch-bonding machine is over-sewn with sewing threads, while simultaneously incorporating the pile threads. [2] Method according to claim 1, in which the pile threads are incorporated directly into the nonwoven fabric to form the pile thread layer. [3] Method according to claim 1, wherein the pile threads are over-sewn with the sewing threads together with the standing thread layer and the weft thread layer to form the pile thread layer. [4] Method according to one of claims 1 to 3, in which the pile thread layer is applied to a first side of the nonwoven fabric and the standing thread layer and the weft thread layer are laid down on a second side of the nonwoven fabric opposite the first side and are fastened with the sewing threads. [5] Method according to one of claims 1 to 4, in which the nonwoven fabric used is a prefabricated calendered spunbonded fabric made of polyester and / or polypropylene with a basis weight of 15 to 80 g / m 2 , preferably 40 g / m 2 is used. [6] Method according to one of claims 1 to 5, in which PES yarns with a fineness of 5 to 16.7 tex, preferably 9 tex, are used as the standing threads. [7] Method according to one of claims 1 to 6, in which PES yarns with a fineness of 5 to 16.7 tex, preferably 9 tex, are used as weft threads. [8] Method according to one of claims 1 to 7, in which polyester silk with a fineness of 3 to 7.6 tex, preferably 5 tex, is used as sewing threads. [9] Method according to one of claims 1 to 8, in which polyester filament yarns with a fineness of 5 to 16.7 tex, preferably 7.6 tex, are used as pile threads, which are guided over a pile plate with a thickness of 0.5 to 5 mm, preferably 2 mm in height. [10] Reinforced carrier material for textile adhesive tapes, comprising a multi-layer composite construction with at least one nonwoven layer made of a fiber nonwoven and / or filament nonwoven, a standing thread layer, a weft thread layer and a pile thread layer, produced by a process according to one or more of claims 1 to 9. [11] Use of a reinforced carrier material according to claim 10 for producing a sound-insulating adhesive tape. [12] Use according to claim 11, wherein an adhesive is applied to the second side of the carrier material, which is opposite the first side on which the pile thread layer is arranged.