Adhesive tape

Abstract

The subject of the invention is an adhesive tape, in particular a wrapping tape for wrapping a cable in a motor vehicle. The adhesive tape is equipped with a textile carrier and at least one adhesive layer applied to one or both sides of the carrier. The carrier is colored with an organic dye consisting of yellow and red pigments. The yellow pigment is based on anthraquinone. According to the invention, perylene-based pigments are used as red pigments.

Description

[0001] This application is a divisional application of the patent application with application number 201980021652.4.

[0002] The present invention relates to an adhesive tape, in particular for wrapping cables in automobiles, comprising a textile carrier and at least one adhesive layer applied to one or both sides of the carrier, wherein the carrier is dyed with an organic dye consisting of yellow and red pigments, wherein the yellow pigment is based on anthraquinone.

[0003] For many years, textile carriers for adhesive tapes have been dyed, initially using inorganic pigments such as those based on carbon black. Such pigments are incorporated into extrudates and can be used in the production of filaments or even filament fabrics, as described in detail in WO 2003 / 033611 [US 2004 / 0253889].

[0004] However, it is increasingly important these days for dyed adhesive tapes to have a protective or warning function. In fact, such adhesive tapes, and in particular wrapping tapes, are often used to prepare cable bundles. For this purpose, the adhesive tape is usually wrapped helically or spirally around the cable bundle, thus bundling the cables to be assembled before or during installation. In principle, this method can also be used to form longitudinal sheaths.

[0005] For example, the warning or reminder function of the tape or wrapping tape in question is necessary and desirable for applications involving cables or cable bundles carrying high voltages greater than 60 volts. This is often the case with hybrid and electric vehicles. Such cable bundles must be marked in orange. In this context, RAL 2003 (light orange) was designated as the standard color in 2010.

[0006] Various methods for applying adhesive tapes are known from the prior art, in particular for wrapping cables in automobiles having the orange color described above. For example, the general teaching according to DE 10 2011 079 114 is effective for organic dyes consisting of mixtures of yellow and red dyes or pigments. The yellow dye is based on anthraquinone. Azo compounds are used for the red dye. However, as an alternative, the red dye can also be a mixture of anthraquinone compounds and azo compounds.

[0007] The dyeing of fibers, filaments or yarns of a textile carrier is carried out by disperse dyeing according to the teaching of DE 10 2011 079 114 A1. Here, synthetic colorants that are insoluble in water are used. For this purpose, the colorant must be finely ground and dissolved in a heated dye bath.

[0008] Generally, in the context of this application and under the According to Chemie Lexikon, 9th edition, 1993, p. 1301, the term "dye" is a collective term or collective name for colorants that are soluble in solvents and / or binders. Dyes are thus contrasted with insoluble pigments, which are inferior to dyes in terms of quantity, structural diversity, and generally also luminosity.

[0009] Therefore, the pigment and in the following according to " Chemie Lexikon, 9th edition, 1995, p. 3439" is understood to mean a coloured or colourless inorganic or organic colourant which is practically insoluble in the medium used. Therefore, according to these definitions, a distinction must be made below between dyes on the one hand and pigments on the other hand.

[0010] In the case of the known teaching according to DE 10 2011 079 114 A1, discoloration or fading of the adhesive tape can still occur due to heat exposure and / or signs of aging. This is particularly problematic over long timescales because, in combination with inevitable contamination, the warning effect is lost.

[0011] For this reason, the applicant's DE 20 2017 107 156 U1 proposes the use of adhesive tapes which use inorganic mineral pigments as dyes in whole or in part. Overall, taking into account the relevant temperature class T4 according to standard LV 312, a temperature stability ("Schutzsys teme für) of typically just over 150° C. for a period of 3000 hours is achieved for the adhesive tapes. in Kraf t fahrzeugen, Prüfrichtlinie” (“Protec tion systems for wire harnesses in motor vehicles, adhesive tapes; testguideline”) (10 / 2009)).

[0012] DE 10 2015 121 562 A1 follows a different approach. Here, a colorant based on a diazo compound is used. This again attempts to achieve a specific temperature resistance, covering at least temperature class T4 in this invention. In particular, all this is achieved by omitting anthraquinone compounds, as anthraquinones are classified as presumed hazardous substances. However, no evidence is provided that this is possible.

[0013] The technical problem underlying the present invention is to provide an adhesive tape for wrapping cables in motor vehicles which is, in particular, temperature-stable and at the same time can be constructed in a simple and cost-effective manner.

[0014] In order to solve this technical problem, within the scope of the present invention, the adhesive tape according to the invention is characterized in that a perylene-based pigment is used as the red pigment.

[0015] Therefore, for the use of organic dyes, the present invention uses yellow pigments for the first time, which have always been based on anthraquinone, as is known, for example, from DE 10 2011 079 114 A1. However, in contrast, no azo compounds or mixtures of anthraquinone compounds and azo compounds are used as red dyes or red pigments. Instead, the present invention intentionally uses perylene, i.e., a special polycyclic aromatic hydrocarbon that is naturally present, for example, in peat and the latest sediments at the bottom of water bodies, and is also present in crude oil. Perylene can also be prepared by heating naphthalene with aluminum chloride or other Lewis acids. In addition, the decarboxylation of perylene tetracarboxylic dianhydride (PTCDA) is known for its use in the preparation of perylene. This is often carried out with the aid of microwaves in the presence of copper as a catalyst.

[0016] Perylene exists as a solid and is characterized by yellow, shiny flakes with an extremely high melting point of over 270°C. Furthermore, because perylene is also an organic semiconductor, perylene and its derivatives are increasingly being used as pigments, while raw material prices are continuously decreasing. This is attributed to the increasing use of perylene as a high-purity material in organic components such as transistors, organic light-emitting diodes (OLEDs), or organic solar cells.

[0017] In this way, according to the present invention, an adhesive tape is provided, in particular an adhesive tape for winding cables in automobiles, which can be produced in a simple and cost-effective manner. Furthermore, the adhesive tape in question is designed to be extremely temperature-stable, with little or no discernible discoloration. In fact, the adhesive tape in accordance with the aforementioned standard LV 312 complies with at least temperature class T3 (125°C), and in particular, even temperature class T4 (150°C). Temperature class T3 corresponds to the fact that the adhesive tape in question must be resistant to temperatures of up to 125°C. To meet temperature class T4, resistance to temperatures of up to 150°C is required. Temperature class T5 even requires temperatures of up to 175°C. This means that, with wound cables, the adhesive tape must withstand these temperatures for 3,000 hours without exhibiting any significant discoloration. Details of this are described in the aforementioned standard or in DE 10 2015 121 562 A1, cited above.

[0018] According to the present invention, the yellow dye is based on anthraquinone-based yellow pigments. Anthraquinones or corresponding pigments are those pigments derived from an anthraquinone base structure. Such perylene and anthraquinone pigments are available in various forms and at low cost and are therefore particularly suitable for the intended use according to the present invention. Furthermore, as described, this allows for particularly high temperature stability.

[0019] To achieve the aforementioned temperature class T3, and especially for adhesive tapes, even T4, special adhesive tapes are often used. In this case, it has proven advantageous if the adhesive layer consists entirely or partially of a solvent-free acrylic hot melt. In principle, other adhesive coatings are also conceivable. However, to achieve the required temperature class of at least T4, acrylic hot melts are often used.

[0020] Furthermore, processing is often performed so that individual or all yarns of the carrier are dyed, in particular the spinnerets are dyed. Thus, by also using an acrylic-based adhesive, it is possible to provide adhesive tapes with a dyed carrier for winding cable harnesses that comply with at least the aforementioned temperature class T3, and in particular even temperature class T4. This is also due, in particular, to the fact that the spinnerets dye individual or all yarns.

[0021] Such spinneret dyeing is characterized in that a mixture of a coloring pigment or a yellow and red pigment is mixed with, for example, a pellet of polyester. The pigment typically has a particle size of less than 0.5 mm. In addition, it has been shown that it is advantageous in this context if, during the spinneret dyeing process, the pigment is present in the extrudate at a concentration of 0.2 to 3.0 wt % based on the polymer spinning mass.

[0022] In principle, it is possible not only to produce spun yarns in the spinneret dyeing process already described above, but also to further process the spun yarns as yarns for textile carriers. In fact, the spun fibers can be further processed into yarns or even staple fibers. Suitable carriers can be woven or nonwoven or combinations thereof. The basis weight of the carrier is generally 20 g / m 2 Up to 500g / m 2 . For adhesive, 20g / m is usually recommended. 2 Up to 200g / m 2 The adhesive layer can be applied to the substrate over the entire surface or in strips.

[0023] The adhesive tape according to the invention can be used to produce a wrapping material, as the adhesive tape discussed above is fed as a wrapping tape by being spiraled or twisted around the cable to be wrapped. However, it is also possible to use the adhesive tape or wrapping tape according to the invention to produce a longitudinal jacket that is wound around the cable as a longitudinally extending longitudinal jacket.

[0024] The carrier can be made and constructed entirely or partially from polyester fibers, polypropylene fibers, polyethylene fibers, or polyamide fibers. The fibers can be further processed into spun yarns or even staple fibers. This allows the aforementioned carriers to be produced, either as woven or nonwoven fabrics, either individually or in combination. In combination with spinneret dyeing of the preferred fibers and the use of the special pigments according to the invention, a particularly temperature-stable adhesive tape is obtained overall.

[0025] Furthermore, if polyester or polyamide-based fibers are used, for example when a fabric is used as a carrier, a high abrasion resistance is also observed, corresponding or comparable to an abrasion resistance according to the aforementioned standard LV 312, which corresponds to average abrasion protection according to class C or even high abrasion protection according to class D. Due to the two pigments used according to the invention, an orange hue (light orange) corresponding to RAL 2003 can be achieved as desired. This is a major advantage that can be seen.

Claims

1. Use of an adhesive tape for winding cables in automobiles, the adhesive tape comprising a textile carrier and at least one adhesive layer applied to one or both sides of the carrier, wherein the carrier at least partially consists of polyester fibers, polypropylene fibers, polyethylene fibers or polyamide fibers and the carrier is dyed with an organic dye consisting of yellow and red pigments, wherein the yellow pigment is based on anthraquinone, using an organic dye based on As red pigment, a pigment of is used, and individual or all yarns of the carrier are spinneret dyed, wherein the coloring pigment is mixed with the granules.

2. The method according to claim 1, wherein the carrier is formed as a woven or nonwoven fabric, alone or in combination.

3. The method according to claim 1 , wherein the carrier has a thickness of at most 500 g / m 2 The basis weight of the adhesive is 20 to 200 g / m 2 The application weight.

4. The method according to claim 1, wherein the adhesive layer is entirely or partially composed of an acrylic hot melt material. 5 . The method according to claim 1 , wherein the adhesive tape satisfies temperature class T3 according to standard LV 312, in particular even temperature class T4. 6 . The method according to claim 1 , wherein the carrier also has a high wear resistance, corresponding to average wear protection of class C according to standard LV 312.