Method for producing an adhesive tape

Abstract

The invention relates to a method for producing an adhesive tape, by: providing a tapelike textile carrier (2), applying a thickener (7) and an aqueous dispersion-based adhesive (8) to the textile carrier (2), and then drying the dispersion-based adhesive (8).

Claims

1. A method of producing an adhesive tape, comprising the steps of: providing a tapelike textile carrier, applying a thickener and an aqueous dispersion-based adhesive to the textile carrier, and drying the dispersion-based adhesive.

2. The method of claim 1, wherein: one side of the textile carrier is coated with a thickener and thereafter an aqueous dispersion-based adhesive is applied to the thickener, and the dispersion-based adhesive is dried.

3. The method of claim 1, wherein: p1 one side of the textile carrier is coated with a thickener and an aqueous dispersion-based adhesive is applied to the other side of the textile carrier, and the dispersion-based adhesive is dried.

4. The method of claim 1, wherein: the thickener is applied over the full area to the textile carrier.

5. The method of claim 1, wherein: the dispersion-based adhesive is applied over the full area.

6. The method of claim 1, wherein: a dual slot die is used in applying the thickener and the dispersion-based adhesive.

7. The method of claim 1, wherein: the dispersion-based adhesive (8) is used with a viscosity of 0.2 Pa*s to 15 Pa*s5 Pa*s.

8. The method of claim 1, wherein: the thickener has a viscosity similar to or the same as that of the dispersion-based adhesive.

9. The method of claim 1, wherein: the dispersion-based adhesive used comprises a polymer dispersion, the polymer being synthesized from: 95.0 to 100.0 wt % of n-butyl acrylate and/or 2-ethylhexyl acrylate 0.0 to 5.0 wt % of an ethylenically unsaturated monomer having an acid function or acid anhydride function.

10. The method of claim 1, wherein: the thickener comprises ASE.

11. The method of claim 1, wherein: the thickener comprises one or more of: carboxymethylcellulose, 2-hydroxyethylcellulose, carboxymethyl-2-hydroxyethylcellulose, methylcellulose, 2-hydroxyethylmethylcellulose, 2-hydroxyethylethylcellulose, 2-hydroxypropylcellulose, 2-hydroxypropylmethylcellulose, and 2-hydroxybutylmethylcellulose.

12. The method of claim 1, wherein: the textile carrier comprises a drawn-loop knit, laid scrim, tape, braid, needle pile textile, felt, woven fabric or a nonwoven web.

13. The method of claim 6, wherein: the dual slot die has a slot width of 100 m to 300 m.

14. The method of claim 1, Wherein: the dried adhesive tape is wound up into a roll.

15. The method of claim 6, wherein: a rate of advance in an advance direction (V) of the textile carrier and a slot distance of the dual slot die are selected such that the dispersion-based adhesive is applied 0.1 to 10 s after the thickener.

16. An apparatus adapted to operate according to the method of claim 1, wherein the apparatus has a coating roll with a longitudinal coating roll direction, a dual slot die having a longitudinal slot direction which is disposed along the longitudinal coating roll direction, a first slot die is in communication with a supply facility with an aqueous thickener, and a second slot die is in communication with a second supply facility with an aqueous dispersion-based adhesive, and the first slot die is disposed ahead of the second slot die in the advance direction (V), and wherein: the textile carrier is adapted to be fed between the dual slot die and the coating roll.

17. The apparatus of claim 16, wherein the apparatus further includes a drying facility after the dual slot die in the advance direction (V).

18. apparatus of claim 16, wherein: the dispersion-based adhesive comprises a polymer dispersion, the polymer being synthesized from: 95.0 to 100.0 wt % of n-butyl acrylate and/or 2-ethylhexyl acrylate 0.0 to 5.0 wt % of an ethylenically unsaturated monomer having an acid function or acid anhydride function.

19. The apparatus of claim 16 wherein: the thickener comprises ASE.

20. The apparatus of claim 16 wherein: the thickener comprises one or more of: carboxymethylcellulose, 2-hydroxyethylcellulose, carboxymethyl-2-hydroxyethylcellulose, methylcellulose, 2-hydroxyethylmethylcellulose, 2-hydroxyethylethylcellulose, 2-hydroxypropylcellulose, 2-hydroxypropylmethylcellulose, and 2-hydroxybutylmethylcellulose.

Description

[0121] The invention is described with reference to a working example and two figures. In the case of the latter

[0122] FIG. 1 shows a sectional view of an apparatus for implementing the adhesive tape production method of the invention, and

[0123] FIG. 2 shows the adhesive tape produced by the method of the invention, in a lateral section

[0124] Depicted in FIG. 1 in a sectional view, schematically, is an apparatus for applying an adhesive layer 1 to a textile carrier 2. The apparatus comprises a coating roll 3, via which the textile carrier 2 is guided. The coating roll 3 is connected to a motor, which rotates the coating roll 3 and gives the textile carrier 2 an advance in an advancement direction V. The direction of rotation can be changed.

[0125] Besides the coating roll 3 there is a dual slot die 4. The coating roll 3 and the dual slot die 4 have the same longitudinal extent in their longitudinal direction L, which stands perpendicularly on the drawing plane. The dual slot die 4 here has a longitudinal extent of its two slots, which are of equal length, of 1600 mm. Other lengths are of course also possible.

[0126] The dual slot die 4 and the coating roll 3 are disposed parallel to one another. They are preferably at a distance from one another and between them form a slot 6 of constant width, through which the textile carrier 2 is passed. During the coating operation, the textile carrier 2 is drawn through the slot 6 and guided around the coating roll 3, from bottom to top right in FIG. 1. During the coating operation, a thickener 7 is first applied by a first slot die 7a to the side of the textile carrier 2 opposite from the coating roll 3. The height of the first slot die 7a is around 100 m, preferably exactly 100 m. The length of the first slot die 7a is 1600 mm.

[0127] A second slot die 8a, disposed successively in the advancement direction V of the textile carrier 2, allows a dispersion-based adhesive 8 to be applied to the thickener 7 which has been applied to an adhesive side 2a of the textile carrier 2. The second slot die 8a has a length of likewise 1600 mm and a height of 300 m. The thickener 7 is applied in the form of a thickener layer to the textile carrier 2, and the dispersion-based adhesive 8 is applied in the form of a dispersion-based adhesive layer to the textile carrier 2.

[0128] Both the thickener 7 and the dispersion-based adhesive 8 have virtually the same viscosity of =3 Pa s. Applied as dispersion-based adhesive 8 is an acrylate adhesive diluted with water. The dispersion-based adhesive 8 is applied with a coat weight of 70 g/m.sup.2. The textile carrier 2 used is a PET web. The thickener 7 has been coated onto the PET web with a coat weight of 2 g/m.sup.2. The thickener used was Sera Print M-PHC. First of all, the thickener 7 sinks immediately into the textile carrier 2 on coating. As a result of the application of dispersion-based adhesive only a few microseconds after the application of thickener, the penetration of the carrier 2 by the thickener 7 is halted and the dispersion-based adhesive 8 undergoes virtually instantaneous thickening. This thickening takes place first of all on the layer side of the adhesive layer 1 facing the carrier 2, and so here as well any substantial penetration of the dispersion-based adhesive 8 into the carrier 2 is prevented. Arranged downstream of the coating roll 3 in the advancement direction V is a drying facility, which is not shown here, but which dries the applied adhesive layer 1that is, the dispersion-based adhesive 8 thickened with thickener 7and provides the completed adhesive tape provided with an adhesive layer 1.

[0129] Shown in FIG. 2, in a section in the cross direction (transverse direction), is the adhesive tape, consisting of a woven fabric carrier 2, on one side of which a layer of a self-adhesive coating 1 based on an acrylate dispersion has been applied.

[0130] The adhesive has been absorbed to an extent of only 15% into the carrier (21), this producing optimum anchoring and at the same time improving the hand tearability of the carrier.

LIST OF REFERENCE SYMBOLS

[0131] 1 adhesive layer

[0132] 2 textile carrier

[0133] 2a adhesive side

[0134] 3 coating roll

[0135] 4 dual slot die

[0136] 6 slot

[0137] 7 thickener

[0138] 7a first slot die

[0139] 8 dispersion-based adhesive

[0140] 8a second slot die

[0141] L longitudinal direction

[0142] V advancement direction