ADHESIVE TAPE FOR JACKETING ELONGATE ITEMS SUCH AS MORE PARTICULARLY CABLE HARNESSES AND METHODS FOR JACKETING

Abstract

An adhesive tape particularly for wrapping cables comprises a textile carrier and a pressure-sensitive adhesive applied on at least one side of the carrier, where starting materials used for the textile carrier comprise fibres of recycled polyethylene terephthalate, where the fraction of the fibres is at least 50 wt % and where the fibres are staple fibres or continuous filaments or are processed to form yarns.

Claims

1. An adhesive tape comprising a textile carrier and a pressure-sensitive adhesive applied on at least one side of the carrier, where starting materials used for the textile carrier comprise fibres of recycled polyethylene terephthalate, where a fraction of the fibres is at least 50 wt % and where the fibres are staple fibres or continuous filaments or are processed to form yarns.

2. Adhesive tape according to claim 1, wherein the fraction of the fibres in the textile carrier is more than 50 wt %, preferably 70 wt % or more, more preferably 90 wt % or more, more preferably 100 wt %.

3. Adhesive tape according to claim 1, wherein the fraction of the fibres in the textile carrier is 100 wt %.

4. Adhesive tape according to claim 1, wherein the carrier is a textile carrier, preferably a nonwoven material or a woven fabric, more particularly a polyethylene terephthalate nonwoven.

5. Adhesive tape according to claim 1, wherein the textile carrier material comprises stitchbonded fabrics, these being textile sheetlike structures which are produced by looping of incorporated knitting threads into a sheetlike base material, and preferably stitchbonded nonwovens, these being textile sheetlike structures with fibre nonwoven as base material which are consolidated by looping of incorporated knitting threads, or by overstitching with additional stitching yarn.

6. Adhesive tape according to claim 1, wherein the textile carrier material comprises knit-bonded nonwovens, these being textile sheetlike structures which are produced, without using threads, by formation of fibre loops from primary fibre nonwoven, and preferably stitchbonded nonwovens, these being textile sheetlike structures with fibre nonwoven as base material which are consolidated by looping of incorporated knitting threads.

7. Adhesive tape according to claim 1, wherein the textile carrier material comprises stitchbonded nonwovens in the form of Maliwatts, preferably having a basis weight of 50 to 200 g/m.sup.2 more particularly 65 to 190 g/m.sup.2, having a linear fibre density of 2 to 5 denier, a fibre length of 30 to 90 mm and/or a stitching thread count of 15 to 25 threads/25 mm.

8. Adhesive tape according to claim 1, wherein the carrier is woven fabric and more preferably is constructed as follows: a thread count in a warp is 10 to 60/cm a thread count in a weft is 10 to 40/cm warp threads possess a yarn weight of between 40 and 400 dtex, more particularly between 44 and 330 dtex, very preferably of 167 dtex weft threads possess a yarn weight of between 40 and 660 dtex, more particularly between 44 and 400 dtex, very preferably of 167 dtex.

9. Adhesive tape according to claim 1, which has an adhesive coatweight, based on an area of the carrier, is between 40 and 160 g/m.sup.2, preferably between 50 and 100 g/m.sup.2, more preferably between 50 and 90 g/m.sup.2.

10. Adhesive tape according to claim 1, wherein the adhesive comprises a self-adhesive coating, preferably based on natural rubber and/or synthetic rubber, acrylate or silicone, preferably natural and/or synthetic rubber.

11. A method of jacketing an elongate item comprising guiding an adhesive tape according to claim 1 in a helical line around the elongate item.

12. A method for jacketing an elongate item comprising enveloping the elongate item in an axial direction by an adhesive tape according to claim 1.

13. An elongate item jacketed with an adhesive tape according to claim 1.

14. A vehicle comprising a jacketed elongate item according to claim 13.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0192] The intention of the text below is to illustrate the adhesive tape in more detail with reference to a number of figures, without thereby wishing to impose any kind of restriction at all.

[0193] In the figures:

[0194] FIG. 1 shows the adhesive tape in a lateral section,

[0195] FIG. 2 shows a detail of a cable loom which is composed of a bundle of individual cables and is jacketed with the adhesive tape of the invention,

[0196] FIG. 3 shows an advantageous application of the adhesive tape, and

[0197] FIG. 4 depicts a ruler for measuring flags.

[0198] Shown in FIG. 1, in a section in the cross direction (transverse section), is the adhesive tape, consisting of a woven fabric carrier 1, one side of which bears an applied layer of a self-adhesive coating 2 based on an acrylate dispersion.

[0199] The adhesive has been absorbed to an extent of 20% into the carrier, thus resulting in optimum anchoring and at the same time improving the hand tearability of the carrier.

[0200] FIG. 2 shows a detail of a cable loom which is composed of a bundle of individual cables 7 and is jacketed with the adhesive tape 11 of the invention. The adhesive tape is passed in a helicoidal movement around the cable loom.

[0201] The detail of the cable loom shown has two turns I and II of the adhesive tape. Further turns will extend toward the left, but are not shown here.

[0202] In a further embodiment for jacketing, two tapes 60, 70 of the invention, furnished with an adhesive, are laminated with their adhesives at an offset (preferably by 50% in each case) to one another, producing a product as shown in FIG. 3.

EXAMPLES

Outline of the Examples

[0203] The adhesive tape of the invention is described below in a preferred embodiment by means of an example, without wishing thereby to subject the invention to any restriction whatsoever.

[0204] In addition, a comparative example is given, which shows an adhesive tape that displays significantly poorer performance.

[0205] An acrylate-based example PSA is applied to a nonwoven carrier, to give an adhesive surface weight of 55 g/m.sup.2.

[0206] The nonwoven is a stitchbonded nonwoven of Maliwatt type with a basis weight of 72 g/m.sup.2, consisting of PET fibres with a length of 64 mm and a thickness of 3 den and of a PET stitching thread with a linear density of 50 dtex, stitched at 22 threads per inch (corresponding to 9 threads/centimetre of nonwoven width).

[0207] In the case of the inventive example B2, the PET fibres consist 50 wt % of recycled PET fibres and 50 wt % of non-recycled PET fibres; in the inventive example 3 they consist 79 wt % of recycled PET fibres and 21 wt % of non-recycled PET fibres; and in the case of the comparative example (B1) they consist 100 wt % of non-recycled PET fibres.

TABLE-US-00001 Abrasion resistance of Peel Peel Unwind Unwind Ultimate unprocessed carrier Storage adhesion, adhesion force force tensile 5 mm mandrel Temp. steel to rear 0.3 m/min 30 m/min strength [double strokes] Weeks [° C.] [N/cm] [N/cm] [N/cm] [N/cm] [N/cm] B1 Standard 5 Fresh 3 4.4 1.7 5.9 36 4 wk 40 2.9 5.4 1.6 6.1 B2 50% recycled 7 Fresh 3.3 4.7 1.5 6.0 32 PET 4 wk 40 2.9 4.9 2.1 5.7 B3 79% recycled 8 Fresh 3.1 4.5 1.7 5.5 36 PET 4 wk 40 3.2 5.3 1.7 6 Flagging Thermal Noise Abrasion resistance (SWAT) short-term attenuation of tape analogously 1 mm ETFE ageing analogously to ISO6722; 7N; cable analogously Elongation to VW60360 5 mm rod diameter 30 d to VW60360, at break [%] [dB(A)] [double strokes] RT 40° C. 130° C. B1 Standard 20 6.1 37 1 0 Test passed 3 13 B2 50% recycled 20 6 49 0 0 Test passed PET 0 8 B3 79% recycled 22 6.4 58 0 0 Test passed PET 1 5

[0208] While the majority of technical and applications tests show a comparable performance spectrum, it is notable that, unexpectedly, a textile carrier wherein the fibres consist of recycled fibres scores better abrasion values than a carrier which uses non-recycled fibres. Moreover, it is evident with the flagging as well, described here as the Single Wire Application Test (SWAT test), that after a test period of 30 days at 40° C., entirely surprisingly, a significantly reduced lifting of the adhesive tape is apparent, becoming evident after accelerated ageing of the rolls for 4 weeks at 40° C.

Assessment Criteria

Implementation of the Tests

[0209] Unless expressly stated otherwise, the measurements are carried out under test conditions of 23±1° C. and 50±5% relative humidity.

Measurement of Flagging Resistance by the SWAT Method

[0210] The SWAT test is utilized in order to investigate the flagging behaviour of adhesive tapes after they have been wound spirally around a cable.

[0211] The test is carried out under standard conditions (23±1° C. and 50±5% relative humidity) and at 40° C. The elevated temperature simulates the more difficult requirements during transport.

[0212] The test uses an adhesive tape 19 mm wide. It is wound manually around a cable jacketed with ETFE (ethylene-tetrafluoroethylene) and having a diameter of 1 mm, four times (1440°), without additional pressure. Scissors are used to cut the adhesive tape.

[0213] A flag on average 5 mm long is assumed to remain unless the end of the adhesive tape is pressed down.

[0214] A total of seven turns around the cable are produced.

[0215] The flags are measured with a ruler after three days, ten days and 30 days under standard conditions. This is shown by FIG. 4. The absolute flagging value is computed by subtracting 5 mm from the flag length actually measured.

[0216] In FIG. 4, therefore, the flagging value is 23 mm (28 mm-5 mm).

[0217] The flagging value reported as the result is the result of the mean flagging values of the seven turns. The test at 40° C. is carried out analogously in customary drying cabinets.

[0218] The adhesive tape of the invention is evaluated subsequently at 40° C. in a drying cabinet by the SWAT method specified.

Measurement of the Peel Adhesion to Steel and to Tape Reverse

[0219] The measurement takes place analogously to the measurement method indicated in the proposed amendment to VW 60360-1, meaning that the test takes place on the one hand, in accordance with DIN EN 1939, to steel (method 1, 180° testing) and on the other hand to the tape reverse (method 2, 180° testing).

Unwind Force

[0220] The unwind force is measured according to the proposed amendment to VW 60360-1 “Protected systems for wiring harnesses—Adhesive Tapes”: 2019-10 at a take-off rate of 0.3 m/min and 30 m/min, respectively.

[0221] Measurement of the noise attenuation according to the proposed amendment to VW 60360-1 “Protected systems for wiring harnesses—Adhesive Tapes”: 2019-10

[0222] The noise attenuation is measured according to the proposed amendment to VW 60360-1 “Protected systems for wiring harnesses—Adhesive Tapes”: 2019-10.

Thermal Short-Term Ageing

[0223] The thermal short-term ageing is measured according to the proposed amendment to VW 60360-1 “Protected systems for wiring harnesses—Adhesive Tapes”: 2019-10. The measurements are made in each case at 130° C. (temperature class B).

Softening Point

[0224] The softening point is understood to be the temperature (or temperature range) at which amorphous or semicrystalline polymers undergo transition from the glassy, hard-elastic state into a soft state. The reduction in the hardness of such substances at the softening point becomes clearly apparent, for example, in that a body placed under load onto a sample of substance is impressed into this sample when the softening point is reached. The softening point is fundamentally above the glass transition temperature, but for the majority of polymers is well below the temperature at which they undergo complete transition into the liquid state.

[0225] The softening point is measured according to ASTM E28-99 (2009), known as Ring & Ball methodology (R&B).

Measurement of Glass Transition Temperatures

[0226] The glass transition temperatures were measured on the DSC 204 F1 “Phönix” Dynamic Scanning calorimeter from Netzsch, Germany, in 25 μl aluminium crucibles with a perforated lid, under a nitrogen atmosphere (20 ml/min gas flow rate). The initial sample mass was 8 1 mg. The samples were measured twice from −140° C. to 200° C. with a heating rate of 10 K/min. The subject of analysis was the 2nd heating curve.

[0227] The method is based on DIN 53 765.

Dynamic Viscosity Measurement

[0228] The viscosity measurement is carried out with a DSR 200 N rheometer from Rheometric Scientific at room temperature and in rotation mode at a shear rate of 0.01 s.sup.−1 using a cone-plate system having a diameter of 25 mm, and alternatively with a shear rate of 10 s.sup.−1.

Gel Content

[0229] The gel content is determined by Soxhlet extraction, which extracts soluble constituents from polymers in a continuous extraction. In the case of determination of the gel content of (aqueous) polyacrylate PSAs, a suitable solvent such as tetrahydrofuran, for example, extracts the soluble fractions of a polymer—the so-called sol—from the insoluble fractions—the so-called gel. Preparation: the composition for extraction is applied to siliconized release paper as a thin film—generally with a layer thickness of 120 μm—and dried for around 12 h at 80° C. (forced-air drying cabinet). The films are kept in a desiccator over desiccant. The Whatman 603 extraction sleeves are dried at 80° C. for 12 h, the empty weight of the sleeves is ascertained, and they are stored in a desiccator prior to use.

Gel Content Determination

[0230] Around 1 g of PSA is weighed into an extraction sleeve. A 100 ml round-bottom flask of the Soxhlet apparatus is filled with 60 ml of tetrahydrofuran and heated to boiling. THF vapours ascend through the vapor tube of the Soxhlet apparatus and condense in the condenser, and THF drips into the extraction sleeve and extracts the sol fraction. In the course of the extraction, the THF I runs back into the flask with the extracted sol. Dissolved sol accumulates increasingly in the flask. After 72 h of continuous extraction, the sol is completely dissolved in the THF. After cooling of the apparatus to room temperature, the extraction sleeve is then removed and dried at 80° C. over 12 h. The sleeves are kept in the desiccator until their mass is constant, after which they are weighed.

[0231] The gel content of the polymer is calculated according to the following formula:

=−/−.Math.100%

where m.sub.1: mass of extraction sleeve, empty [0232] m.sub.2: mass of extraction sleeve+polymer [0233] m.sub.3: mass of extraction sleeve+gel

Flexural Stiffness

[0234] The flexural stiffness is determined using a Softometer KWS basic 2000 mN (from Wolf Messtechnik GmbH). (MD) stands for machine direction, meaning that the flexural stiffness is determined in the machine direction.