STRIP-SHAPED PLASTIC OBJECT

Abstract

The invention relates to a strip-shaped plastic object (1), having a longitudinal extent (2) and, perpendicular thereto, a strip width (3) and a strip thickness (4), wherein the strip-shaped plastic object (1) comprises an at least partially crystalline, thermoplastic plastic material, which is stretched monoaxially, or predominantly monoaxially, in the direction of the longitudinal extent (2). The strip width (3) and the longitudinal extent (2) form an upper (5) and a lower surface (6), which surfaces (5, 6) are spaced apart from each other by the strip thickness (4), wherein at least one of the surfaces (5, 6) has an embossment (7). The embossment (7) is formed by embossing impressions (8) distributed over the strip width (3) and over the longitudinal extent (2), wherein the embossing impression (8) has a length (9), a width (10), and a depth (11) extending in the direction of the strip thickness (4). In a top view of the embossing impression (8), the boundary line (12) thereof is formed by a closed oval curve.

Claims

1-19. (canceled)

20. A plastic strip (1), having a longitudinal extent (2) and, perpendicular thereto, a strip width (3) and a strip thickness (4), wherein the plastic strip (1) comprises an at least partially crystalline, thermoplastic plastic material, which is stretched monoaxially, or predominantly monoaxially, in the direction of the longitudinal extent (2), and wherein the plastic strip (1), when viewed in the direction of the longitudinal extent (2) and in the direction of the strip width (3), has a continuous cross-section in each case, and wherein the strip width (3) and the longitudinal extent (2) form an upper (5) and a lower surface (6), which surfaces (5, 6) are spaced apart from each other by the strip thickness (4), and wherein at least one of the surfaces (5, 6) has an embossment (7), said embossment (7) being formed by embossing impressions (8) distributed over the strip width (3) and over the longitudinal extent (2), said distributed embossing impressions (8) of the embossment (7) forming columns in the direction of the longitudinal extent (2) and rows in the direction of the strip width (3), wherein in a top view of the embossing impression (8), the boundary line thereof is formed by a closed oval curve, the embossing impression (8) has a length (9), a width (10), and a depth (11) extending in the direction of the strip width (4), wherein viewed in the longitudinal extent (2), a row spacing (14) between two consecutively arranged embossing impressions (8) is 2 to 2.5 times the length (9) of the embossing impression (8), and viewed in the band width (3), a column spacing (13) between two adjacently arranged embossing impressions (8) is less than or equal to twice the width (10) of the embossing impression (8).

21. The plastic strip according to claim 20, wherein the boundary line (12) of the embossing impression (8) is designed to be elliptical or oval.

22. The plastic strip according to claim 21, wherein the length (9) is in the region of 1.0 mm-2.8 mm and the width (10) is in the region of 0.5 mm-1.2 mm, wherein the combinations 2.0?0.84 mm, or 1.25?0.52 mm, or 2.5?1.05 mm respectively are preferred.

23. The plastic strip according to claim 20, wherein the boundary line (12) of the embossing impression (8) is designed to be circular.

24. The plastic strip according to claim 23, wherein the diameter (18) of the embossing impression (8) is in the region of 0.8 mm-1.6 mm, but the diameter (18) is preferably 0.89 mm or 1.42 mm.

25. The plastic strip according to claim 20, wherein the length (9) of the embossing impression (8) is oriented in the direction of the longitudinal extent (2) and the width (10) of the embossing impression (8) is oriented in the direction of the strip width (3).

26. The plastic strip according to claim 20, wherein the orientation of the columns is pivoted by an angle in relation to the longitudinal extent (2) and/or the orientation of the rows is pivoted by an angle in relation to the strip width (3).

27. The plastic strip according to claim 20, wherein a column offset (15) and a row offset (16) are provided between consecutively arranged rows when viewed in the direction of the longitudinal extent (2), and in particular, the column offset (15) is 50% of the column spacing (13) and the row offset (16) is 50% of the row spacing (14).

28. The plastic strip according to claim 20, wherein the depth (11) of the embossing impression (8) is in the region of 50 ?m-300 ?m, especially 150 ?m.

29. The plastic strip according to claim 20, wherein both surfaces (5, 6) comprise an embossment (7).

30. The plastic strip according to claim 29, wherein the embossment (7) is different on both surfaces, and in particular the respective embossing impressions (8) of both embossments (7) have a different boundary line (12).

31. The plastic strip according to claim 29, wherein, in the top view of the plastic strip (1), an offset is provided in the direction of the longitudinal extent (2) and/or an offset is provided in the direction of the strip width (3) between the embossment (7) on both surfaces (5, 6).

32. The plastic strip according to claim 31, wherein the offset is 50% of the column spacing (13) and/or 50% of the row spacing (14).

33. The plastic strip according to claim 29, wherein, in the top view of the plastic strip (1), the orientation of both embossments (7) is pivoted by an angle in relation to one another, in particular by 90?.

34. The plastic strip according to claim 33, wherein the angle is 90? and the embossing impressions (8) of both embossments (7) are designed such that, if both embossments (7) are arranged without pivoting, they coincide with respect to their length (9) and width (10), and/or their width (10) and diameter respectively.

35. The plastic strip according to claim 20, wherein the boundary line (12) is made up of straight sections and/or different curve radii.

Description

[0030] To facilitate understanding of the invention, it is explained below in greater detail with the aid of the following figures, which show highly simplified schematic representations of:

[0031] FIG. 1 a) and b) a possible embodiment of the strip-shaped plastic object according to the invention with an oval embossment, in a top view and in a sectional view;

[0032] FIG. 2 another possible embodiment with a circular embossment.

[0033] FIG. 1 shows the strip-shaped plastic object 1 according to the invention, first in a top view (FIG. 1a) and then as a sectional view (FIG. 1b). The plastic object 1 comprises a longitudinal extent 2 and, perpendicular thereto, a strip width 3 and a strip thickness 4. The strip width 3 and the longitudinal extent 2 form an upper 5 and a lower 6 surface, which surfaces 5, 6 are spaced apart from each other by the strip thickness (4).

[0034] One of the surfaces 5, 6 has an embossment 7, said embossment 7 being formed by embossing impressions 8 distributed over the strip width 3 and over the longitudinal extent 2. An embossing impression 8 has a length 9, a width 10, and a depth 11 extending in the direction of the strip thickness 4. In a top view of the embossing impression 8, the boundary line 12 thereof is formed by a closed oval curve, wherein the boundary line 12 is designed to be elliptical or oval according to a first embodiment. According to one embodiment, the length 9 is in the region of 1 mm to 2.8 mm and the width 10 is in the region of 0.5 mm to 1.2 mm. More preferable variations have a length of 1.25 mm and a width of 0.52 mm, or a length of 2 mm and a width of 0.84 mm, or a length of 2.5 mm and a width of 1.05 mm respectively. It is preferable if the distributed embossing impressions 8 of the embossment 7 are arranged in columns in the direction of the longitudinal extent 2 and in rows in the direction of the strip width 3, wherein there is a column spacing 13 between the columns and a row spacing 14 between the rows. According to the preferred embodiments, the combination of column spacing and row spacing is 0.83/2.63 mm and 1.54/4.50 mm.

[0035] In particular, the column spacing 13 is less than or equal to twice the width 10 of the embossing impression 8. The row spacing 14 is in the region of 2 to 2.5 times the length 9 of the embossing impression 8.

[0036] To ensure that the embossing impressions 8 are packed as compactly as possible to form the embossment 7, it is proposed that adjacently arranged columns of a row are arranged with a column offset 15, and adjacently arranged rows of a column are arranged with a row offset 16. The column offset 15 is preferably 50% of the column spacing 13 and the row offset 16 is preferably 50% of the row spacing 14.

[0037] It is explicitly noted that the embossment is only shown in a portion of the illustrated surface to simplify the drawing and ensure that the figures are clear. The embossment is of course distributed over the entire surface.

[0038] FIG. 1b shows a sectional view from FIG. 1a, illustrating a possible variation in which an embossment 7 is arranged on the upper 5 and lower 6 surface. According to a possible development, an offset 17 is provided between the two embossments 7 on both surfaces 5, 6, wherein only one offset 17 can be shown in the direction of the longitudinal extent 2 for presentation reasons. However, it is also possible for there to be no offset 17 between the two embossments 7, and both embossments 7 are thus arranged on the surfaces 5, 6 such that they are congruent. It is also possible to find that two different embossments 7 are often arranged on both surfaces 5, 6, and in particular for the embossing impressions 8 on the upper surface to differ from those on the lower 6 surface. It is also possible for the embossing impressions 8 to additionally or alternatively be arranged such that they are pivoted by an angle in relation to the longitudinal extent.

[0039] FIG. 2 shows another possible embodiment of the plastic object 1 according to the invention with an embossment 7 applied to an upper surface 5, wherein the embossment 7 is formed by embossing impressions 8 distributed in a regular pattern over the surface 5. According to this embodiment, the embossing impressions have a boundary line 12, said boundary line 12 being circular in shape. The diameter of the embossing impression 8 is in the region of 0.8 mm to 1.6 mm, but a diameter of 0.89 mm or 1.42 mm is preferred.

[0040] The individual embossing impressions 8 of the embossment 7 are in turn distributed evenly over the upper surface 5 and form columns and rows in the arrangement. In this case, the individual columns are arranged in a column spacing 13 or a row spacing 14 of two consecutive rows with the same column orientation. According to the preferred embodiments, the combination of column spacing and row spacing is 1.23/2.49 mm and 1.80/3.62 mm.

[0041] To ensure that the embossing impressions 8 are packed as compactly as possible to form the embossment 7, it is also conceivable according to this embodiment that there should be a column offset 15 between adjacent columns of a row, and/or a row offset 16 between adjacently arranged rows of a column. It is preferable if this column offset 15 or row offset is 50% of the diameter of the embossing impression 8.

[0042] FIGS. 1a and 2 each show a top view of the embossing impressions 8, but the flanks of the embossing impressions 8 are not shown for reasons of simplicity. These flanks are visible in the sectional view in FIG. 1b. The specified preferred diameters of 0.89 mm for a fine embossment and 1.42 mm for a coarse embossment thus correspond to the diameter of the embossing impression 8 at the base of the embossment (in the depth of the plastic material). A stamp used to produce an embossing impression 8 may have a trapezoidal cross-section, for example, and has the preferred diameter values of 0.89 mm or 1.42 mm respectively at the tip. A diameter at the base of 1.23 mm or 1.76 mm respectively is obtained if the stamp height is 0.4 mm with a flank angle of 23?. As the embossing stamp and thus the individual stamps, as already described, are never pressed into the plastic strip the full 0.4 mm, the diameters of the embossing impressions 8 on the strip surface (5, 6) are correspondingly smaller and can be calculated by trigonometry if the actual embossing depth is known.

[0043] Due to two effects when applying or introducing the embossing impressions 8, the embossing impressions 8 will have an appearance that is slightly out-of-round despite the circular stamps. The plastic strip stretched in the longitudinal direction runs underneath an embossing roller or between two embossing rollers. Due to the stretching process, the stamp pressing into the strip will be able to displace the plastic material more easily in the transverse direction of the strip than in the longitudinal direction. After passing through, when the stamp is removed, it is possible to see in the longitudinal direction that there is a slight backwards movement of the plastic material, with the result that the circular embossed embossing impression 8 remains as a slightly oval shape.

[0044] The second effect is identified as a relaxation of the stretched plastic strip. The plastic strip runs through the embossing device under considerable tension in some cases. When this tensile stress no longer applies, e.g. after leaving the manufacturing device or due to a slight heating process which may in some cases be applied after the first process, this causes the plastic strip to contract, principally in the longitudinal direction. This contraction may be as much as 3-12%, which will in turn lead to a deformation (compression in the longitudinal direction) of the circular embossment.

[0045] These advantageous embodiments ensure that there is very good force transference from a clamping device to the plastic strip, wherein this force transference or application of force acts primarily in the direction of the longitudinal extent. At the same time it is also possible to guarantee that an adequate force or kinetic energy can be transferred from the welding device onto the plastic object in order to reliably perform the welding process, usually friction welding. Thus, a strip-shaped plastic object is advantageously created, said object being particularly well adapted or optimized to the requirements in everyday use.

[0046] Finally, it is noted that the same components are provided with the same reference numerals or the same component names in embodiments with different descriptions, which means that the disclosures contained in the description as a whole can be transferred accordingly to the same components with the same reference numerals or the same component names. Location information selected in the description, such as, for example, above, below, at the side of, etc, also refers to the figure immediately described and illustrated, and this location information should be transferred accordingly to the new location if this location changes.

[0047] FIG. 2 shows another, possibly independent embodiment of the strip-shaped plastic object, again using the same reference numerals or component names as used in FIG. 1 above for the same parts. In order to avoid unnecessary repetitions, reference is made to the detailed description in FIG. 1 above.

[0048] The embodiments illustrate possible variations of the plastic strip according to the invention, with the proviso that the invention is not restricted to the variations of these embodiments specifically described, but that various combinations of the individual variations of the embodiments are also possible and these possible variations lie within the abilities of persons skilled in the art in this technical field on the grounds of teaching in relation to technical possibilities posed by the present invention.

[0049] Individual features or combinations of features from the different illustrated and described embodiments may also represent independent inventive solutions, or solutions according to the invention.

[0050] The object forming the basis for the independent inventive solutions may be taken from the description.

[0051] All information relating to ranges of values in the description of the invention should be understood as including any and all partial regions of these ranges, e.g. specifying 1 to 10 should be understood to mean that all partial ranges from the lower limit of 1 and the upper limit of 10 are included, i.e. all partial ranges begin with a lower limit of 1 or higher, and end with an upper limit of 10 or lower, e.g. 1 to 1.7, or 3.2 to 8.1, or 5.5 to 10.

[0052] Above all, the individual embodiments illustrated in the figures may constitute the object of independent solutions according to the invention. The related objects and solutions according to the invention can be found in the detailed descriptions of these figures.

[0053] Finally, as a matter of form, it should be noted that the strip-shaped plastic object or its component parts is/are sometimes not shown to scale and/or may be enlarged and/or reduced in size to facilitate understanding of the structure of the strip-shaped plastic object.

LIST OF REFERENCE NUMERALS

[0054] 1 plastic object [0055] 2 longitudinal extent [0056] 3 strip width [0057] 4 strip thickness [0058] 5 upper surface [0059] 6 lower surface [0060] 7 embossment [0061] 8 embossing impression [0062] 9 length [0063] 10 width [0064] 11 depth [0065] 12 boundary line [0066] 13 column spacing [0067] 14 row spacing [0068] 15 column offset [0069] 16 row offset [0070] 17 offset