Nonwoven havng a corrugated structure, intermediate product, and method for producing a nonwoven having a corrugated structure

Abstract

The invention relates to a three-dimensional structured nonwoven, which is formed from staple fibers (F1, F2, F3). In order to be able to produce such a nonwoven using simple means, the invention proposes providing groove channels (R) on at least one of its surfaces (O), which channels are milled into the surface (O) provided with the groove channels.

Claims

1. A three-dimensional structured nonwoven (V) composed of staple fibers (F1, F2, F3), characterized in that groove channels (R) exist on at least one of its surfaces (0), which channels are milled into the surface (0) provided with the groove channels (R).

2. The three-dimensional structured nonwoven (V) according to claim 1, characterized in that in a region of the nonwoven (V) that borders directly on the groove channels (R), the fibers (F1, F2) are preponderantly oriented parallel to the groove channels (R).

3. The three-dimensional structured nonwoven (V) according to claim 2, characterized in that the fibers (F1, F2) oriented preponderantly parallel to the groove channels (R) are present in a region that delimits the groove channels (R) laterally.

4. The three-dimensional structured nonwoven (V) according to claim 2 or 3, characterized in that the nonwoven (V) has a different orientation of the fibers (F3) below the groove channels (R).

5. The three-dimensional structured nonwoven (V) according to claim 4, characterized in that the nonwoven (V) has a random orientation of the fibers (F3) below the groove channels (R).

6. The three-dimensional structured nonwoven (V) according to one of the preceding claims, characterized in that at least 10 groove channels (R) are formed per nonwoven width.

7. The three-dimensional structured nonwoven (V) according to one of the preceding claims, characterized in that the groove channels (R) have a maximum depth of 5 mm.

8. The three-dimensional structured nonwoven (V) according to one of the preceding claims, characterized in that the groove channels (R) run parallel to one another.

9. The three-dimensional structured nonwoven (V) according to one of the preceding claims, characterized in that the groove channels (R) are configured to be continuous over the length of the nonwoven (V).

10. The three-dimensional structured nonwoven (V) according to one of the preceding claims, characterized in that the groove channels (R) have a corrugated progression.

11. An intermediate product for the production of a nonwoven (V) structured according to one of the preceding claims, wherein the intermediate product is present in the non-consolidated state, characterized in that the intermediate product is formed by a stack of fibers (F1, F2, F3), into at least one surface of which groove channels (R) are milled.

12. A method for producing a nonwoven (V) configured according to one of the above claims, comprising the following work steps: a) making available a fiber stack composed of fibers (F1, F2, F3), b) milling groove channels (R) into a surface (0) of the fiber stack, c) consolidating the fiber stack provided with the groove channels (R) to produce the nonwoven (V).

13. The method according to claim 12, characterized in that the length of the fibers (F1, F2, F3) amounts to at least 10 mm.

14. The method according to one of claim 12 or 13, characterized in that the fibers (F1, F2, F3) have a gauge of 0.7-70 dtex.

15. The method according to one of claims 12 to 14, characterized in that in working step b), the groove channels (R) are milled by means of a rotating roll that is provided with a fitting.

16. The method according to claim 15, characterized in that the fitting consists of a fitting set, of pins, of hooks or of disks.

17. The method according to one of claims 12 to 16, characterized in that in working step c), consolidation of the fiber stack to produce the nonwoven (V) takes place by means of application of an adhesive that glues the fibers (F1, F2, F3) to one another.

18. The method according to one of claims 12 to 17, characterized in that in working step c), consolidation of the fiber stack to produce the nonwoven takes place by means of application of heat, so that fibers (F1, F2, F3) that lie against one another melt, at least partially, in the region of their contact zone, and a material-fit connection occurs between the fibers (F1, F2, F3), due to the material of the fibers (F1, F2, F3) melting into one another.

Description

[0043] In the following, the invention will be explained using an exemplary embodiment.

[0044] FIG. 1 shows a nonwoven in cross-section, in the production (running) direction.

[0045] FIG. 2 shows a detail of the nonwoven according to FIG. 1 in a top view.

[0046] The nonwoven V has groove channels R, which have been milled into the nonwoven V with a depth t. In FIG. 1, the fiber cross-sections of fibers F1, F2 are indicated with dots, the fibers being oriented parallel to the groove channels R, since groove milling occurred in the material running direction ML.

[0047] Below the milling depth t, the nonwoven V has any desired structure. Thus, the fibers F3 can form a random-orientation nonwoven or a multi-layer paneled nonwoven.

[0048] The groove channels R are produced using a rapidly rotating roll, not shown here, which is provided with a fitting. The fitting can consist of a fitting set, pins, hooks or disks.

[0049] For the production of the nonwoven V, a strip-shaped fiber stack produced in conventional manner, for example by means of the airlay method, is made available as an intermediate product; the fibers F1, F2, F3 are present in random orientation in this product.

[0050] Due to the milling processing of the surface O of the nonwoven V to be provided with the groove channels R, the fibers that are situated in the region of the groove channels R to be produced are torn out of the surface of the fiber stack by the fitting of the rotating roll. At the same time, due to the relative movement between the fibers F1, F2, F3 that remain in the fiber stack, the fitting of the tool and/or the fibers that have been torn out, the fibers F1, F2, which laterally delimit the corresponding groove channel R, are brought into an orientation parallel to the straight-line progression of the groove channels R. In contrast, the fibers F3 that are present in the thickness regions of the nonwoven V that lie deeper relative to the surface O remain in their original random orientation, so that fibers F3 are present in random orientation also below the groove channels R.

[0051] After milling of the groove channels R, the nonwoven V can be consolidated by using one of the methods already mentioned above, which are known for this purpose from the state of the art.

[0052] A nonwoven V according to the invention is therefore characterized in that it has groove channels R so as to have a three-dimensional structure. The groove channels R are milled. The fibers F1, F2 that delimit the groove channels R laterally are oriented parallel to the progression of the respective groove channels R.

[0053] Accordingly, the invention relates to a three-dimensional structured nonwoven V, which is formed from staple fibers F1, F2, F3. So as to be able to produce such a nonwoven V using simple means and with a minimized need for fibers F1, F2, F3 required for production, the invention proposes providing groove channels R on at least one of the surfaces O of the fiber stack, which grooves are milled into the surface O.

REFERENCE SYMBOLS

[0054] F1, F2 fibers in orientation parallel to the groove channels R [0055] F3 fibers in random orientation [0056] ML material running direction [0057] O surface of the nonwoven V [0058] R groove channels [0059] T depth of the groove channels [Translator's Note: In the text the lower case letter t was used.] [0060] V nonwoven