Adhesive tape for wrapping elongate material such as especially cable harnesses and method for wrapping

Abstract

The invention pertains to an adhesive tape, more particularly for wrapping elongate material such as cable harnesses in a motor vehicle, comprising a carrier having a top side and a bottom side, the carrier, based on the cross direction, having a width B.sub.T, there being provided, on at least one long edge on the bottom side of the carrier, a strip of adhesive which has a width B.sub.K of at least 3 mm and at most 30% of the width B.sub.T, characterized in that as well as the strip of adhesive on the bottom side of the carrier, there is at least one polymer strip which extends over a width B.sub.P of at least 60%, preferably 75%, more preferably 90%, very preferably 100%, of the residual width B.sub.RB—not coated with the strip of adhesive—of the carrier.

Claims

1. Adhesive tape comprising a carrier having a top side and a bottom side, the carrier, based on the cross direction, having a width B.sub.T, there being provided, on at least one long edge on the bottom side of the carrier, a strip of adhesive which has a width B.sub.K of at least 3 mm and at most 30% of the width B.sub.T, wherein in addition to the strip of adhesive on the bottom side of the carrier, there is at least one polymer strip which extends over a width B.sub.P of at least 60% of a residual width B.sub.RB of the carrier, wherein said at least one polymer strip is not coated with the strip of adhesive, and wherein said at least one polymer strip has a thickness of 40 to 300 μm.

2. Adhesive tape according to claim 1, wherein there is provided, on each of both long edges on the bottom side of the carrier, a strip of adhesive, said strips having a width B.sub.K of at least 3 mm and of at most 30% of the width B.sub.T, there being present, between the strips of adhesive on the bottom side of the carrier, at least one polymer strip which extends over a width B.sub.P of at least 60% of the residual width B.sub.RB of—not coated with the strip of adhesive—of the carrier.

3. Adhesive tape according to claim 1, wherein the strip or strips of adhesive each finish flush with the long edge or long edges of the carrier.

4. Adhesive tape according to claim 1, wherein the width B.sub.K of the strips of adhesive is at least 10 mm and/or at maximum at most 25% of the width B.sub.T.

5. Adhesive tape according to claim 1, wherein the width B.sub.K of the strips of adhesive is between 5 and 40 mm.

6. Adhesive tape according to claim 1, wherein the width of one strip of adhesive B.sub.K1 is smaller by a factor of 0.5 to 0.8 than the width of the other strip of adhesive B.sub.K2.

7. Adhesive tape according to claim 1, wherein the strip or strips of adhesive have a thickness of 40 to 300 μm.

8. Adhesive tape according to claim 1, wherein the thickness or the coat weight of one strip of adhesive is smaller by a factor of 0.5 to 0.8 than the thickness or the coat weight of the other strip of adhesive.

9. Adhesive tape according to claim 1, wherein the width B.sub.T of the carrier is between 20 and 200 mm.

10. Adhesive tape according to claim 1, wherein the carrier has a basis weight of 30 to 250 g/m.sup.2.

11. Adhesive tape according to claim 1, wherein the carrier used comprises a woven, nonwoven or knitted fabric.

12. A method for wrapping elongate material, said method comprising enveloping the elongate material in an axial direction by the adhesive tape according to claim 1.

13. Elongate material wrapped with an adhesive tape according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the text below, the intention is to elucidate the invention in more detail, referring to a number of figures and also an example, without thereby wishing to impose any unnecessary limitation on the invention.

(2) FIG. 1 shows an inventive adhesive tape with a strip of adhesive,

(3) FIG. 2 shows an inventive adhesive tape with a strip of adhesive applied with an offset,

(4) FIG. 3 shows a third inventive adhesive tape with two strips of adhesive,

(5) FIG. 4 shows the material jacketed with the inventive adhesive tape from FIG. 1, and

(6) FIG. 5 shows a fourth inventive adhesive tape.

(7) In cross section in FIG. 1 is an inventive adhesive tape having a carrier 10 which has a width B.sub.T (45 mm, for example). On the bottom side of the carrier 10 is a strip 11 of an adhesive with a width B.sub.K of 10 mm and hence of approximately 22% of the width B.sub.T.

(8) Beside the strip 11 of adhesive on the bottom side of the carrier is a polymer strip 15, which extends over a width B.sub.P of 100% of the residual width B.sub.RB, not coated with the strip 11 of adhesive, of the carrier; in other words, B.sub.P is equal to B.sub.RB.

(9) In contrast to the adhesive tape from FIG. 2, in which the strip is applied with an offset having a width B.sub.VS, the adhesive strip 11 finishes flush with the long edge of the carrier 10.

(10) Beside the strip 11 of adhesive on the bottom side of the carrier is a polymer strip 15, which extends over a width B.sub.P of 95% of the residual width B.sub.RB, not coated with the strip 11 of adhesive, of the carrier; in other words, B.sub.P is not equal to B.sub.RB.

(11) FIG. 3 shows a third inventive adhesive tape, having two strips 11 and 12 of adhesive. On the bottom side of the carrier 10 there is a first strip 11 of adhesive and a second strip 12 of adhesive. The strips 11 and 12 of adhesive run in the longitudinal direction of the carrier 10, also called the machine direction, and both finish flush with the long edges of the carrier 10.

(12) Between the strips 11 and 12 of adhesive on the bottom side of the carrier is a polymer strip 15, which extends over a width B.sub.P of 100% of the residual width B.sub.RB, not coated with the strips 11 and 12 of adhesive, of the carrier; in other words, B.sub.P is equal to B.sub.RB.

(13) On the top side of the carrier 10 there is a third strip 14 of adhesive. The third adhesive strip 14, viewed in the cross section of the carrier 10, is in the region of the polymer strip 15 between the two strips 11 and 12 of adhesive on the bottom side of the carrier.

(14) FIG. 4 shows the material—here, cable 7 for a cable loom in the automotive segment—jacketed with the inventive adhesive tape from FIG. 1.

(15) The cable 7 is enveloped by the adhesive tape in such a way that the adhesive strip 11 lies on the adhesive-strip-free end of the carrier 10.

(16) FIG. 5 shows a fourth inventive adhesive tape, having two strips 11 and 13 of adhesive. On the bottom side of the carrier 10 there is a first strip 11 of adhesive and a second strip 13 of adhesive, with the second strip 13 of adhesive having a lower width B.sub.K2 than the first strip 11 of adhesive, which has a width B.sub.K1.

(17) The strips 11 and 13 of adhesive run in the longitudinal direction of the carrier 10, also called the machine direction, and both finish flush with the long edges of the carrier 10.

(18) Between the strips 11 and 13 of adhesive on the bottom side of the carrier is a polymer strip 15, which extends over a width B.sub.P of 100% of the residual width B.sub.RB, not coated with the strips 11 and 13 of adhesive, of the carrier; in other words, B.sub.P is equal to B.sub.RB.

(19) Before the invention is represented plastically by means of examples, a description is given of the measurement methods used.

Test Methods

(20) The measurements are carried out—unless explicitly stated otherwise—under test conditions of 23±1° C. and 50±5% relative humidity.

(21) Peel Strength (Peel Adhesion, PA)

(22) For measurement of the peel adhesion forces, test strips 19 mm wide were adhered without bubbles to a finely sanded (emery paper with FEPA grit size 240) plate of stainless steel, and pressed down with a rubber-clad 2 kg roller at a speed of 10 m/min. The steel plate and the protruding end of the adhesive tape were then clamped into the ends of a tensile testing machine in such a way as to form a peel angle of 180°. After a predetermined time had been allowed to elapse for the bond to “take” (30 minutes unless otherwise indicated), the adhesive tape was peeled from the steel plate with a speed of 300 mm/min. The peel adhesion is reported in N/cm.

(23) Static Glass Transition Temperature T.sub.g

(24) The static glass transition temperature is determined by dynamic scanning calorimetry in accordance with DIN 53765. The data for the glass transition temperature T.sub.g relates to the glass transformation temperature value T.sub.g in accordance with DIN 53765:1994-03, unless otherwise indicated in a particular case, and especially sections 7.1 and 8.1, although with uniform heating and cooling rates of 10 K/min in all heating and cooling steps (compare DIN 53 765; section 7.1; note 1).

(25) Molecular Weights

(26) The weight-average molecular weight m.sub.W is determined here by means of gel permeation chromatography (GPC). The eluent used is THF with 0.1 vol % of trifluoroacetic acid. Measurement takes place at 25° C. The pre-column used is PSS-SDV, 5μ, 10.sup.3 Å, ID 8.0 mm×50 mm. Separation is carried out using the columns PSS-SDV, 5μ, 10.sup.3 Å and also 10.sup.5 Å and 10.sup.6 Å each with ID 8.0 mm×300 mm. The sample concentration was 4 g/l, the flow rate 1.0 ml per minute. Measurement is made against PMMA standards. (μ=μm; 1 Å=10.sup.−10 m).

(27) Abrasion Resistance

(28) The abrasion resistance is determined in accordance with LV312-1, likewise on the basis of a defined test method. The adhesive tapes are classified according to their abrasion resistance, for a mandrel diameter of 5 mm, as shown in Table 2:

(29) For this purpose, the adhesive tape under test is first adhered to a mandrel or metal rod 5 mm in diameter. A scraper tool having a needle diameter of 0.45 mm is then used, on the basis of a weight force 7 N, to determine the number of strokes required to break right through the adhesive tape. The greater the number of strokes, the more abrasion-resistant the adhesive tape in question.

(30) TABLE-US-00001 TABLE 2 Abrasion resistance classification to LV 312-1 (10/2009) Abrasion class Requirement A no abrasion protection <100 strokes B low abrasion protection 100-499 strokes C moderate abrasion protection 500-999 strokes D high abrasion protection 1000-4999 strokes E very high abrasion protection 5000-14999 strokes F extremely high abrasion protection ≥15000 strokes

(31) The examples which follow are intended to serve to illustrate the invention without wishing to limit it.

EXAMPLES

(32) A total of six different adhesive tapes were produced. Example 1 is an adhesive tape without a polymer layer; Examples 2 to 6 each have a polymer layer, with a different polymer basis.

(33) The carrier taken in each case was a plain-woven PET fabric 45 mm wide and of 130 g/m.sup.2, its two long edges each bearing a strip of adhesive, applied flush, with a width of 10 mm.

(34) Applied between the strips of adhesive was a polymer strip with a width of 25 mm, likewise with a coat weight of 70 g/m.sup.2.

(35) Carrier: 45 mm wide woven PET fabric, plain weave, 130 g/m.sup.2

(36) Strips of adhesive: finishing flush with the long edge of the carrier 10 mm wide, 70 g/m.sup.2 coat weight acrylate-based adhesive

(37) Polymer strip: adjacent flush to the strips of adhesive; 25 mm wide, 70 g/m.sup.2 coat weight polymer basis various

(38) TABLE-US-00002 Abrasion Coat resistance Abrasion weight [No. of class # Coating type Name [g/m.sup.2] strokes] LV312 1 — — — 286 B 2 Acrylic latex Acronal 500D 70 812 C 3 Natural rubber SMR CV 50 70 490 B 4 Natural rubber Neotex FA 70 348 B latex 5 Synthetic rubber Kraton D1101 70 793 C AS 6 EPDM Vistalon 6602 70 669 C

(39) By means of the various polymer strips, the abrasion resistance is increased significantly by comparison with the bare carrier.

(40) Furthermore, the rolls with polymer strips exhibit better winding characteristics, owing to the uniform thickness present over the entire width of the carrier. The wound rolls possess significantly cleaner edges and exhibit no gapping, in other words no holes or gaps within the coatings between the carrier plies within the roll of adhesive tape.