EP4041837A1

EP4041837A1 - Adhesive tape

Info

Publication number: EP4041837A1
Application number: EP20775235.3A
Authority: EP
Inventors: René RAMBUSCH; Timo Leermann
Original assignee: Certoplast Technische Klebebander GmbH
Current assignee: Certoplast Technische Klebebander GmbH
Priority date: 2019-10-11
Filing date: 2020-09-16
Publication date: 2022-08-17
Also published as: CN114555738A; WO2021069185A1; DE202019105633U1; US20230065871A1

Abstract

The invention relates to an adhesive tape, in particular wrapping tape, for sheathing automotive cables, having a mostly textile support and at least one adhesive coating layer applied to one side or both sides of the textile support, and the textile support being manufactured entirely or partially from bio-based polymer fibers and/or polymer yarns, characterized in that the textile support is a velours support or includes such a velours support.

Description

duct tape

Description:

The invention relates to an adhesive tape, in particular a winding tape for sheathing cables in automobiles, with a predominantly textile carrier and with an adhesive coating applied to one or both sides of the carrier, the textile carrier being wholly or partly made of bio-based polymer fibers and / or polymer threads .

Adhesive tapes and, in particular, wrapping tapes for sheathing cables in automobiles are used to combine the cables in question or also to protect them from mechanical abrasion. In this context, not only the media resistance to, for example, oil and gasoline, but also the required temperature resistance are of great importance. In fact, such adhesive tapes and in particular wrapping tapes are typically used in the temperature range between -50 ° C. up to +150 ° C. and more. In order to prevent any rattling noises at this point from the cable harness equipped with this example, additional sound emissions are aimed at. Also increased abrasion resistance to prevent the body from chafing.

The abrasion resistance of the adhesive tape can be determined based on the standard LV 312 (2009) using abrasion classes. Details on this and on the test methods used are described, inter alia, in DE 20 2012 103 975 U1. For example, abrasion class B corresponds to the fact that the adhesive tape in question withstands at least 100 strokes until it is worn through, when it is stuck on a 5 millimeter mandrel, taking into account a weight load of 10 N. In addition to the noise-dampening effect, the required resistance to abrasion, media and temperature, there is often also the requirement that the adhesive tape or wrapping tape in question must be able to be torn manually. This is because the wrapping tapes in question are typically wrapped around the cable bundle to be appropriately equipped by an assembly worker. This can be done in a spiral or helical manner. In principle, a so-called longitudinal sheathing of the cable bundle to be equipped with this can also be implemented with the aid of such an adhesive tape or also a wrapping tape. In any case, the processing often requires the adhesive tape to be cut to length, which in the simplest case is done by simply tearing it off. As a result, hand tearability is of particular importance, which is given or can be given by way of example and in accordance with the explanations in DE 600 31 332 T2 if the adhesive tape has a tear strength in the transverse direction of less than 10N. Basically, hand tearability can also simply and simply be assessed subjectively on the basis of tests.

More recently, products and technical devices, especially in the automotive sector, have been subject to increased requirements for improved recyclability and resource-saving production. For example, from DE 20 2017 106 797 U1, films and, in particular, protective films, some of which are made from a bio-based polymer, are already known. The bio-based polymer is in turn obtained from a plant-based raw material.

In the context of the generic teaching according to DE 202019 100588 U1 of the applicant, the possibility is already shown of realizing an adhesive tape and in particular wrapping tape for wrapping cables in automobiles in such a way that the textile carrier is at least partially based on bio-based polymers is made. For this purpose, the textile carrier can be made from bio-based polymer fibers and / or polymer threads. Nonwovens, knitted fabrics, woven fabrics or combinations are mentioned as possibilities for such a textile carrier. This has basically proven itself, but still offers room for further improvements, in particular to the effect that adhesive tapes with reduced noise emissions are made available.

The invention is based on the technical problem of further developing such an adhesive tape and in particular winding tape for sheathing cables in automobiles in such a way that all application-specific requirements in connection with resource-saving production are met and rattling noises are effectively suppressed at the same time.

To solve this technical problem, the invention proposes, in the context of the invention, for a generic adhesive tape and, in particular, wrapping tape for sheathing cables in automobiles, that the predominantly textile carrier is designed as a velor carrier or contains one. I. E. the carrier is predominant, i. H. More than 50% by mass, textile, but can also contain non-textile components such as foils, which accordingly make up less than 50% by mass or weight of the carrier.

The invention therefore first and foremost falls back on a special textile carrier which is made entirely or partially from the bio-based polymer fibers and / or polymer threads. In addition, in one variant, the textile carrier is designed overall as a velor carrier. In another variant, the predominantly textile-based carrier can in principle also be designed as a laminate, that is to say as a multi-layer carrier. While in The former case where the carrier is single-layer and is formed solely from the velor carrier, the variant of the carrier designed as a laminate corresponds to the carrier being multi-layered, with at least one layer of the carrier representing a velor carrier. The remaining layers can be textile and non-textile layers as long as the mass or weight fraction of the textile components of the carrier is more than 50% of its total mass or its total weight.

In this variant, the procedure can be, for example, that the carrier is designed as a laminate and, in addition to the velor carrier, also has a film carrier. In this case, the carrier is finally made in two layers and is composed on the one hand of the velor carrier and on the other hand the film carrier. It has proven useful here if the film carrier is arranged between the velor carrier and the adhesive coating. As a result, the velor carrier with its velor loops has an arrangement such that the velor loops of the velor carrier point outwards. In contrast, the adhesive coating is applied on the opposite side of the adhesive tape to the film carrier, which in turn is arranged between the adhesive coating and the velor carrier.

In order to achieve a particularly resource-saving Her position in this context, the film carrier can be designed as a bio-based polymer film carrier. In this context, it has proven useful if the film carrier is designed as a biopolyester film carrier, that is to say is produced as a film carrier based on biopolyester.

The biopolyester is advantageously designed as a bio-based PET (polyethylene terephthalate). The basic building blocks of this bio-based polymer are made from renewable raw materials instead of crude oil. The renewable raw materials can be those based on vegetable materials such as starchy plants. In addition, such bio-based polymers can also be produced using lactic acid.

In any case, the bio-based polymer film or the bio-based polymer film carrier and in particular the biopolyester film carrier can be realized and implemented in such a way that, in the example, PET is produced by polycondensation from monoethylene glycol (or ethylene glycol) and terephthalic acid. In this context, the monoethylene glycol can be produced from sugar cane molasses. Terephthalic acid can be produced bio-based or petrochemically.

Either way, the velor backing, with its velor loops advantageously pointing outwards, ensures that the adhesive tape and in particular wrapping tape implemented in this way can not only be produced in a particularly resource-saving manner, but also has particular advantages with regard to any noise emissions. In fact, the outward-facing velor loops effectively dampen any rattling noises. This means that the velor loops are found on the upper side of the adhesive tape pointing outwards, whereas the adhesive coating is regularly present on the opposite inside.

If the adhesive tape is wrapped around a cable bundle or a cable harness, for example in a spiral or helical manner, the adhesive layer points inwards or ensures that the adhesive tape is fixed on the cable bundle or cable harness, so that the velor loops as part of the velor backing automatically point outwards and so for that The necessary noise suppression and, in particular, the suppression of any rattling noises. This is where the main advantages can be seen.

The velor loops pointing outwards typically have a loop length in the range from 0.5 mm to 5 mm and in particular 0.8 mm to 2 mm. Such a loop length has proven to be particularly favorable and practicable, because on the one hand the velor loops do not protrude significantly from the adhesive tape and thus any entanglements with screws, edges or other sharp-edged projections in the interior of the motor vehicle are avoided. On the other hand, the specified length spectrum for the velor loops is sufficient to achieve effective noise damping at the same time.

The velor carrier generally has a mesh density of more than 5000 per dm ² , in particular the mesh density is in the range from about 25,000 per dm ² to 50,000 per dm ² . This design provides a dense surface and the corresponding velor loops ensure a particularly large-area noise-dampening effect.

The velor carrier is generally a knitted fabric velor carrier with the velor loops facing outwards. The velor loops usually form an outer bar in a velvet weave, for example. In principle, a super velvet binding is also possible in this context. In addition to this outer bar with a velvet weave or super velvet weave, an inner bar with a tricot weave can also be realized underneath. The velor loops are advantageously knitted not only into the outer bar, but also into the inner bar below. Filaments or filament threads based on polyamide or polyester are typically used to produce the velor backing. Since bio-based polymer threads are mostly taken into account in this context, the velor backing is made entirely of filaments based on bio-polyamide or bio-polyester. The biopolyester for the production of the filaments of the velor carrier is advantageously PET, which in turn is produced in a manner comparable to the PET for the production of the film carrier. This means that in this case too, for example, the monoethylene glycol required for this can be produced from sugar cane molasses. The additionally required terephthalic acid may in turn be produced petrochemically or bio-based. This means that raw materials comparable to those used for the filaments for the manufacture of the velor carrier are used for the optional film carrier.

In this context, it has proven particularly useful if the velor backing is made from filaments based on biopolyamide. The invention further recommends that the monomers or amines of the bio-polyamide consist entirely or in part of castor oil. The additionally required acid or carboxylic acid can in turn be produced in a manner comparable to terephthalic acid for PET, predominantly petrochemically, but recently also bio-based. In principle, mixed forms are also conceivable.

As already stated, the predominantly textile carrier can be configured as a single layer, in which case the textile carrier is designed solely as a velor carrier. In addition, the carrier can also be designed in multiple layers. In this case, the carrier is advantageously designed in two layers and is composed on the one hand of the outwardly facing velor carrier and on the other hand the film carrier to which the adhesive coating is applied. Either way, the carrier typically has a basis weight in Range from 20 g / m ² to 500 g / m ² . The thickness or material thickness of the carrier is usually between 0.5 mm and 3 mm in order to ensure good processability.

The adhesive coating is then applied either to the back of the velor carrier or the inner bar or to the interposed film carrier. An application weight in the range from 20 g / m ² to 500 g / m ^{2 has} proven to be particularly favorable here. A synthetic rubber adhesive, a hotmelt adhesive, an adhesive based on acrylate, an adhesive based on silicone, polyurethane, polyether and / or polyolefin are used, for example, as the adhesive. In this context, the adhesive can in principle be crosslinked after the coating, in particular by radiation crosslinking. In addition, the adhesive coating can be applied to the carrier over the entire surface or in strips.

As a result, an adhesive tape and in particular a wrapping tape for sheathing cables in automobiles is made available, which can be produced in a particularly resource-saving manner. This is because the predominantly textile carrier is wholly or partially made from bio-based polymer fibers and / or polymer threads. As a rule, filament threads are used at this point, i.e. continuous fibers made from the bio-based polymer. The bio-based polymer is usually one based on bio-polyamide or bio-polyester.

If special abrasion resistance is required, it has proven useful if the velor backing is made from filaments based on biopolyamide. In fact, in this way, adhesive tapes can be produced which at least achieve abrasion class B and predominantly even abrasion class C or even D according to LV 312 (2009), as already described above has been. At the same time, the adhesive tape produced in this way can be torn by hand, with tear strengths in the transverse direction of the adhesive tape of typically 20 N and in particular even 10 N being observed, taking into account an adhesive tape width in the range up to approx. 50 mm.

Due to the fact that the carrier is predominantly based on biopolyamide or biopolyester, not only are the abrasion resistances already described above achieved, but such a carrier is also distinguished by high media and temperature resistance. In connection with the special soundproofing ability achieved by the outwardly standing velor loops, the requirements necessary for the chosen application are met.

The fineness of the filaments based on biopolyamide for the realization of the velor backing is usually between 20 dtex and 100 dtex. By resorting to polyamide at this point, not only can the abrasion resistance be set as high as described, but the elongation at break of the carrier material can also be specified so that it is in the range between 30% and 70%. The tear strength of the entire adhesive tape is typically in the range from about 100 N / cm to 200 N / cm, specifically in the longitudinal direction of the adhesive tape. In the transverse direction of the adhesive tape, tear strengths that are lower by a factor of 10 are observed at this point, which are achieved, for example, by making perforations in the carrier in the transverse direction. This usually happens before the adhesive coating is applied. Along these perforations, tear strengths in the transverse direction of about 10 N / cm or even less are observed, so that the desired hand tearability is present in said transverse direction, which corresponds to tear forces in the example of 20 N / cm at a maximum. In the single FIG. 1, an exemplary embodiment of the adhesive tape according to the invention is shown. In fact, FIG. 1 shows an adhesive tape which is used as a wrapping tape for bundling or sheathing cables in automobiles. A predominantly textile carrier, which is a velor carrier 1, is part of its basic structure. The velor carrier 1 is equipped with an adhesive coating 2. The adhesive coating 2 covers the velor carrier 1 at least in some areas and can consequently be applied over the entire surface or in strip form.

A film carrier 3 is provided between the adhesive coating 2 and the velor carrier 1. The velor carrier 1 has velor loops 4 facing outwards. The velor loops 4 primarily take over the sound insulation and form an outer bar 5. The outer bar 5 has a velvet weave.

In addition, an inner bar 6 in a tricot weave according to the exemplary embodiment is also provided, which is arranged in the direction of the film carrier 3 between the outer bar 5 and the said film carrier 3. Both the velor carrier 1 and the film carrier 3 are each made bio-based, as was previously described in detail.

Claims

Patent claims:

1. Adhesive tape, in particular winding tape for sheathing cables in automobiles, with a predominantly textile carrier, and with an adhesive coating (2) applied to one or both sides of the carrier, the textile carrier being made entirely or partially from bio-based polymer fibers and / or polymer threads is, characterized in that the carrier is designed as a velor carrier (1) or includes one.

2. Adhesive tape according to claim 1, characterized in that the velor carrier (1) has outwardly facing velor loops (4) with a loop length in the range from 0.5 mm to 5 mm, in particular 0.8 mm to 2 mm.

3. Adhesive tape according to claim 1 or 2, characterized in that the velor carrier (1) has a mesh density of more than 5000 per dm ² .

4. Adhesive tape according to one of claims 1 to 3, characterized in that the velor carrier (1) is designed as a knitwear velor carrier with the outwardly facing velor loops (4) in the form of an outer bar (5) in, for example, a velvet weave.

5. Adhesive tape according to one of claims 1 to 4, characterized in that the velor carrier (1) is made from film materials based on bio-polyamide or bio-polyester.

6. Adhesive tape according to claim 5, characterized in that the monomers of the biopolyamide consist entirely or partially of castor oil.

7. Adhesive tape according to one of claims 1 to 6, characterized in that the carrier is designed as a laminate and, in addition to the velor carrier, also has a film carrier (3).

8. Adhesive tape according to claim 7, characterized in that the film carrier (3) is arranged between the velor carrier (1) and the adhesive coating (2).

9. Adhesive tape according to claim 7 or 8, characterized in that the film carrier (3) is designed as a bio-based polymer film carrier (3).

10. Adhesive tape according to claim 9, characterized in that the film carrier (3) is designed as a biopolyester film carrier.

11. Adhesive tape according to one of claims 1 to 10, characterized in that the carrier has a weight per unit area of 20 g / m ² to 500 g / m ² .

12. Adhesive tape according to one of claims 1 to 11, characterized in that the carrier has a material thickness of 0.5 mm to 3 mm.

13. Adhesive tape according to one of claims 1 to 12, characterized in that the adhesive coating (2) has an application weight in the range from 20 g / m ² to 200 g / m ² .

14. Adhesive tape according to one of claims 1 to 13, characterized in that the adhesive used is a synthetic rubber adhesive, a hotmelt adhesive, an acrylate-based adhesive, a silicone, polyurethane, polyether and / or polyolefin-based adhesive.

15. Adhesive tape according to one of claims 1 to 14, characterized in that the adhesive coating (2) is applied over the entire surface or in strips to the carrier.