TREAD CONSTRUCTION

Description

[0001] The invention relates to a tread for use in vehicle tires and a vehicle tire comprising a corresponding tread. Also disclosed are methods for producing corresponding treads and vehicle tires, as well as a use of such treads for reducing electrostatic charging during operation of vehicle tires. The subject matter of the invention is defined in the appended claims.

[0002] A key component of modern pneumatic vehicle tires, which in many cases is significantly responsible for the performance characteristics of these products, is the tread. Today, treads usually consist of several different components, in particular various rubber materials, which can be obtained by vulcanization from vulcanizable rubber compounds. Such treads are usually produced by coextrusion of various vulcanizable rubber compounds and their structure is usually described by their cross-section, which, apart from any complex surface profiling, usually runs uniformly across the entire tread strip that encompasses the pneumatic vehicle tire. Accordingly, in this context, they are often referred to as tread patterns.

[0003] In cross-sectional view, most treads, especially those used on cars and trucks, comprise one or more rubber materials intended to come into contact with the road surface during later use, and whose properties are optimized for this purpose. This layer, which essentially acts as a top layer, is made from a vulcanizable rubber compound, sometimes referred to as a "cap compound."

[0004] Beneath the rubber material intended for road contact is usually a base layer (often referred to as a "base"). In the majority of cases, this base layer serves primarily to create sufficient adhesion between the cover layer intended for road contact and the other components of the pneumatic vehicle tire, thus ensuring a high bond strength between the tread and the other components of the pneumatic vehicle tire. This is regularly necessary because the cover layers intended for road contact often lack sufficient adhesion, and the bond strength created by direct attachment to the other components of a pneumatic vehicle tire would often be insufficient.

[0005] Those skilled in the art are aware that a tread must exhibit a certain degree of conductivity throughout its entirety for the vast majority of applications. However, in many cases, the rubber material of the cover layer lacks sufficient electrical conductivity. In these cases, the electrical conductivity of the entire tread is typically achieved by a base mixture in the base layer that exhibits increased electrical conductivity. For this purpose, for example, a strand of material from the base layer is guided to the top of the tread, thereby creating an electrically conductive connection between the surface of the tread and the base layer. A corresponding design is also referred to as a "center carbon beam" (CCB).

[0006] In state-of-the-art pneumatic vehicle tires, the base layer therefore regularly plays a key role. In fact, in some cases, it is even possible to increase the performance of the pneumatic vehicle tire in specific performance ranges through a specific design of the rubber materials used in the base layer, particularly through specific coordination with the rubber materials used in the cover layer. However, for many applications, the base layer and the rubber material used in it tend to degrade the performance properties, resulting in a conflict of objectives between the need for the base layer to ensure sufficient tackiness or electrical conductivity and an inherently disadvantageous influence on the driving characteristics of the pneumatic vehicle tire.In many cases, this conflict of objectives means for the expert that with conventional bases and usual tread patterns, the performance characteristics are generally worse the larger the proportion of the base in the tread pattern, ie the area proportion of the base in the cross-section through the tread.

[0007] US 2014367008 A1 discloses a pneumatic tire capable of dissipating static electricity generated in a vehicle body or the tire to a road surface. US 2002185210 A1 discloses a method for improving the grip of a tire casing on dry ground, and in particular, the use of a special tread structure that enables this grip to be improved. US 2014283964 A1 discloses an antistatic vehicle tire and a method for manufacturing such a tire. US 6070630 A discloses a rubber tire with a carbon black-reinforced carcass and a specific rubber tread construction.

[0008] It was the object of the present invention to eliminate or at least reduce the disadvantages known from the prior art.

[0009] In particular, it was the object of the present invention to provide a tread for use in vehicle tires which ensures sufficient electrical conductivity of the entire tread even when using poorly conductive rubber materials in the cover layer.

[0010] One of the objectives here was to ideally reduce the proportion of the base in the tread, whereby the rubber material used in the base should advantageously not be present on the upper side of the tread intended for road contact, in particular not in the form of a CCB formed from the base.

[0011] It was an object of the present invention that the production of the treads to be specified should be particularly easy, ie particularly time- and cost-efficient, to carry out, in particular in comparison with those tread profiles which have a CCB protruding from the base and reaching to the surface of the tread.

[0012] It was an object of the present invention to improve the performance properties of vehicle tires comprising a corresponding tread by reducing the proportion of the base and the absence of a CCB.

[0013] In this respect, it was an object of the present invention that the treads to be specified should, ideally, require only minor modifications to existing equipment during production. Accordingly, a supplementary object of the present invention was to provide a method for producing corresponding treads and a method for producing vehicle tires based thereon.

[0014] The above-mentioned objects are achieved by the subject matter of the invention as defined in the claims. Preferred embodiments of the invention emerge from the subclaims and the following statements.

[0015] Such embodiments, which are designated as preferred below, are combined in particularly preferred embodiments with features of other embodiments designated as preferred. Combinations of two or more of the embodiments designated as particularly preferred below are thus very particularly preferred. Likewise preferred are embodiments in which a feature of one embodiment designated as preferred to any extent is combined with one or more further features of other embodiments designated as preferred to any extent. Features of preferred methods and uses emerge from the features of preferred treads and vehicle tires.

[0016] The invention relates to a tread for use in vehicle tires, having an upper side intended for road contact and an underside intended for connection to other components of a vehicle tire, comprising: a) a central element comprising: i) a base comprising a first rubber material, wherein a surface of the base is arranged on the underside of the tread, ii) a cover layer connected to the base comprising a second rubber material, wherein a surface of the cover layer is arranged on the upper side of the tread, and b) a first flank element comprising a third rubber material and a second flank element comprising a fourth rubber material, wherein the first flank element and the second flank element are arranged on opposite sides of the central element, and wherein the third rubber material and the fourth rubber material have a specific resistance of 10 10< Ω m or less at 25 °C, characterized in that the third rubber material and the fourth rubber material extend on the sides of the central element from the underside of the tread to the top side of the tread, wherein the central element consists of the base and the cover layer, wherein the mass fraction of the third rubber material in the first flank element is 90% or more, based on the mass of the first flank element, and wherein the mass fraction of the fourth rubber material in the second flank element is 90% or more, based on the mass of the second flank element, or wherein the first flank element and the second flank element comprise at least a fifth rubber material,wherein the fifth rubber material is arranged on the side of the flank element facing away from the central element.

[0017] The treads according to the invention are suitable for use in vehicle tires, particularly pneumatic vehicle tires. In accordance with the understanding of those skilled in the art, a tread has an upper surface, which is later intended for contact with the road surface, and a lower surface, through which the connection to the remaining components of the pneumatic vehicle tire is established.

[0018] The tread according to the invention comprises a central element formed from a base layer and a cover layer bonded to the base layer. The cover layer is intended for contact with the road surface, whereas the base layer provides the necessary tack during the manufacturing process, i.e., usually before vulcanization, to firmly bond the tread to the other components of a pneumatic vehicle tire. The central element contained in the tread according to the invention can thus itself be regarded as a typical tread comprising a base layer and a cover layer, as is known from the prior art.

[0019] However, the treads according to the invention now comprise a first and a second flank element, each of which itself comprises a rubber material. These are arranged on opposite sides of the central element and frame it, so to speak, which is advantageously particularly easy to implement in terms of construction, in particular in comparison with a construction which has a central CCB. The rubber materials contained in the flank elements extend according to the invention from the underside of the tread to the upper side of the tread and, due to their comparatively low specific resistance of 10 10< Ω m or less, i.e. in words ten to the power of ten, enable sufficient overall electrical conductivity of the entire tread, since unwanted electrostatic charging by the flank elements can be efficiently avoided.

[0020] With corresponding treads according to the invention, particularly high-performance vehicle tires with excellent conductivity properties can be produced in a time- and cost-efficient manner. Furthermore, since sufficient overall electrical conductivity can be ensured by the sidewall elements, it is possible to advantageously reduce the proportion of the base and the first rubber material contained therein in the tread.

[0021] In the context of the present invention, resistivity refers to the specific electrical volume resistance of materials, which is a quantity familiar to those skilled in the art for characterizing materials. The measurement of the specific electrical volume resistance of rubber materials is carried out in accordance with common practice, either according to DIN EN ISO 3915 from 1999, which is used in particular for particularly conductive materials, or according to IEC 60093 from 1993, which is used for high specific electrical volume resistances. Even though IEC 60093 from 1993 will be relevant for the majority of rubber materials, the choice of standard depends on the specifications of both standards and the properties of the respective material being tested.

[0022] Even though it would be possible in principle for the central element to comprise additional components, it is in accordance with the invention if the central element consists only of the specified components. Accordingly, it is also preferred if the base and cover layers consist at least predominantly, preferably essentially entirely, of the respective rubber materials. Accordingly, the invention relates to a tread, wherein the central element consists of the base and the cover layers.

[0023] Also preferred is a tread according to the invention, wherein the mass fraction of the first rubber material in the base is 90% or more, preferably 95% or more, particularly preferably 99% or more, very particularly preferably 99.5% or more, based on the mass of the base, and / or wherein the mass fraction of the second rubber material in the cover layer is 90% or more, preferably 95% or more, particularly preferably 99% or more, very particularly preferably 99.5% or more, based on the mass of the cover layer.

[0024] Those skilled in the art will understand that the treads according to the invention can advantageously be designed with a thin base, since this does not necessarily determine the electrical properties of the tread. Accordingly, it is particularly advantageous if the base is also designed to be correspondingly thin. Thus, a tread according to the invention is preferred, wherein the volume of the base is smaller than the volume of the cover layer. Also preferred is a tread according to the invention, wherein the volume of the first flank region and / or the second flank region is greater than the volume of the base.

[0025] Even if it is potentially conceivable to design the flank regions differently, from a manufacturing perspective and with a view to achieving the most consistent driving characteristics possible, it is preferred if the flank regions are designed essentially the same. Thus, a tread according to the invention is preferred, wherein the volume of the first flank region and the second flank region is essentially the same. Accordingly, a tread according to the invention is also preferred, wherein the third rubber material and the fourth rubber material are identical.

[0026] Since the flank regions in the treads according to the invention primarily serve to ensure sufficient electrical conductivity, but in many cases will fall short of the second rubber material in terms of optimizing driving characteristics, it is preferable to make the flank regions comparatively small. Therefore, a tread according to the invention is preferred in which the combined volume of the first flank region and the second flank region is smaller than the volume of the central region.

[0027] With regard to the other design features, similar principles apply to the treads according to the invention as to prior art treads. Thus, a tread according to the invention is generally relevant in practice, with the tread having a profile on the upper side.

[0028] Also regularly relevant in practice is a tread according to the invention, wherein the tread is strand-shaped, wherein the length of the tread is greater than the width of the tread, wherein preferably the base and / or the cover layer and / or the first flank region and / or the second flank region, preferably both layers and both flank regions, are strand-shaped.

[0029] A tread according to the invention is preferred, wherein the tread has a thickness in the range of 10 to 60 mm, preferably in the range of 20 to 30 mm.

[0030] The inventor has recognized that the advantageous properties of the treads according to the invention can be further improved if the rubber materials used in the sidewall elements are designed to be particularly conductive. This reliably prevents the static charging of the treads or the vehicle tires during operation, and it is advantageously possible to design the sidewall elements to be particularly small and material-saving. Therefore, a tread according to the invention is preferred, wherein the third rubber material and the fourth rubber material have a specific resistance of 10 9 < Ω m or less, preferably of 10 8 < Ω m or less, particularly preferably of 10 7 < Ω m or less, at 25°C.

[0031] It will be understood by those skilled in the art that the advantages of the method according to the invention are particularly evident when the cover layer intended for road contact itself has a relatively high specific resistance. Thus, a tread according to the invention is preferred, wherein the second rubber material has a specific resistance of more than 10 10< Ω m, preferably more than 10 11< Ω m, particularly preferably more than 10 12< Ω m, at 25°C.

[0032] It can be seen as an advantage of the treads according to the invention that, apart from the defined specific resistances, they are very flexible with regard to the selection of rubber materials, so that materials that are traditionally used in tire manufacturing can advantageously be used. A tread according to the invention is preferred, wherein the first rubber material and / or the second rubber material and / or the third rubber material, and / or the fourth rubber material, preferably all rubber materials, can be produced by vulcanizing vulcanizable rubber mixtures, wherein the vulcanizable rubber mixtures preferably comprise at least one diene rubber and at least one filler.

[0033] In this context, it has proven advantageous to use natural rubber and adhesive resins as the base material to optimize sufficient adhesion in the vulcanizable rubber mixtures. Therefore, a tread according to the invention is preferred, wherein the first rubber material can be produced by vulcanizing a vulcanizable rubber mixture comprising natural rubber, preferably in a content of 20 phr or more, particularly preferably 30 phr or more, and / or one or more adhesive resins, preferably in a content of 2 phr or more.

[0034] To obtain rubber materials particularly suitable for use in the sidewall elements, it has proven effective to add relatively large amounts of carbon black to the vulcanizable rubber mixture. A tread according to the invention is preferred, wherein the third rubber material and / or the fourth rubber material can be produced by vulcanizing a vulcanizable rubber mixture comprising carbon black, preferably in a content of 20 phr or more, particularly preferably 30 phr or more.

[0035] A tread according to the invention is preferred, wherein the cover layer is connected to the base and / or the first flank element and / or the second flank element, preferably to the base and both flank elements, in the contact area by a material-to-material connection, wherein the material-to-material connection was preferably produced or promoted by a vulcanization process.

[0036] The inventor has succeeded in identifying particularly favorable geometries and arrangements for the sidewall regions that are particularly suitable for use in pneumatic vehicle tires for high-performance applications. In a first embodiment, it is particularly advantageous if the proportion of the upper side of the tread that is filled by the cover layer is maximized. A trapezoidal structure of the elements used advantageously makes it possible to keep the proportion of the base particularly low. In this respect, a tread according to the invention is preferred, wherein the first sidewall element and / or the second sidewall element, preferably both sidewall elements, have a trapezoidal cross-section, wherein the longer base side of the trapezoid is preferably located on the underside of the tread.Additionally or alternatively, a tread according to the invention is preferred, wherein the central element has a trapezoidal cross-section, wherein the longer base side of the trapezoid is preferably located on the upper side of the tread.

[0037] Particularly with a view to simple production, it is particularly advantageous if the flank elements also consist essentially of the corresponding rubber materials and do not comprise any further materials. According to the invention, therefore, in a first alternative, a tread is provided, wherein the mass fraction of the third rubber material in the first flank element is 90% or more, preferably 95% or more, particularly preferably 99% or more, very particularly preferably 99.5% or more, based on the mass of the first flank element, and wherein the mass fraction of the fourth rubber material in the second flank element is 90% or more, preferably 95% or more, particularly preferably 99% or more, very particularly preferably 99.5% or more, based on the mass of the second flank element.

[0038] As an inventive alternative to the embodiment described above, the sidewall elements can also be formed in multiple parts, although in this case, the third and fourth rubber materials must still extend from the underside to the top side of the tread according to the invention in order to ensure the necessary electrical conductivity of the tread. However, it is advantageously possible to form parts of the sidewall elements from other rubber materials, whose physicochemical properties can be specifically designed and adapted to the subsequent performance requirements of the pneumatic vehicle tire, so that, for example, the running properties of the tread near the shoulder area of ​​the pneumatic vehicle tire can be specifically modified.According to the invention, in a second alternative, there is a tread, wherein the first flank element and the second flank element comprise at least a fifth rubber material, wherein the fifth rubber material is preferably arranged on the side of the flank element facing away from the central element, and wherein the fifth rubber material is preferably located on the upper side of the tread, wherein the fifth rubber material is particularly preferably not located on the underside of the tread, wherein the fifth rubber material and the second rubber material are very particularly preferably identical.

[0039] In a preferred embodiment of the multi-part flank elements described above, these can be designed such that the strand-like flank elements have an angular profile in the cross-section through the tread, for example, by being L-shaped. These angular profiles can, for example, be nestled against a substantially rectangular central element and thus provide a receptacle for additional rubber materials on the side facing away from the central element, so that the surface area of ​​the upper side of the tread for the third and fourth rubber materials can be selected to be comparatively low.A tread according to the invention is preferred, wherein the first flank element and / or the second flank element have an angular profile in cross-section, preferably with an angle of 90° or more, so that the third rubber material and / or the fourth rubber material are located on the sides of the central element and on the upper side of the tread, wherein the proportion of the upper side of the tread formed by the third rubber material and / or the fourth rubber material is preferably in the range from 5 to 30%, preferably in the range from 10 to 20%.

[0040] In the course of developing the present invention, the inventor has identified a particularly preferred embodiment. Surprisingly, in cases where the base does not have to contribute to the electrical conductivity of the tread, it is possible to form this not as a flat surface, but rather only from individual partial layers, which extend through the tread as spaced-apart strands on the underside of the tread, thus forming a base divided into partial layers. This procedure advantageously makes it possible to ensure sufficient tackiness on the underside of the unvulcanized tread and at the same time to reduce the proportion of the first rubber material, i.e.The rubber material of the base layer is particularly significantly reduced on the tread. In a synergistic manner, the contact area between the base layer formed from partial layers and the cover layer, relative to the mass of the base layer used, is particularly high due to the increased total surface area of ​​the base layer formed from partial layers, thus achieving a particularly favorable bond strength. It has been shown that the adhesiveness of the tread thus obtained is sufficient to reliably place it on the other components of a pneumatic vehicle tire and to secure it by vulcanization.Particularly preferred is therefore a tread according to the invention, wherein the base comprises two or more, preferably three or more, particularly preferably four or more, separate and spaced apart, preferably equidistantly spaced, partial layers, wherein all of the partial layers are connected to the cover layer, wherein all of the partial layers lie with a surface on the underside of the tread.

[0041] In light of the above, it will be understood by those skilled in the art that the invention also relates to a vehicle tire that is particularly advantageous due to the advantageous electrical conductivity of the tread and the low proportion of the base in the tread. Accordingly, the invention also relates to a vehicle tire, in particular a pneumatic vehicle tire, comprising a tread according to the invention as the tread.

[0042] This also discloses the use of a tread according to the invention as a tread of a vehicle tire, in particular a pneumatic vehicle tire, for reducing the electrostatic charge during operation.

[0043] Also disclosed is a method for producing a tread according to the invention, comprising the steps: v1) Producing an unvulcanized green tread by coextruding a first vulcanizable rubber mixture, a second vulcanizable rubber mixture, a third vulcanizable rubber mixture, and a fourth vulcanizable rubber mixture, and v3) Vulcanizing the unvulcanized green tread. Vulcanization can advantageously be carried out under the usual conditions that are well known to the person skilled in the art from the prior art and, in case of doubt, can be readily adapted to the vulcanization properties of the vulcanizable rubber mixtures used in the components.

[0044] The subsequent manufacture of a vehicle tire will generally comprise the arrangement of the green tread on a tire carcass prior to vulcanization, with further components, such as belt plies, optionally being provided between these components. Conventional tire construction methods known to those skilled in the art can be used for this purpose. Thus, finally, a method for producing a vehicle tire, in particular a pneumatic vehicle tire, is disclosed, comprising the steps of the method according to the invention for producing a tread, and, prior to step v3), the step: v2) producing a green vehicle tire comprising the unvulcanized green tread.

[0045] Preferred embodiments of the invention are explained and described in more detail below with reference to the accompanying figures. Fig. 1 shows a schematic cross-sectional view of a tread according to the prior art; Fig. 2 shows three schematic cross-sectional views of treads according to the invention in a first, second, and third embodiment; Fig. 3 shows three schematic cross-sectional views of treads according to the invention in a fourth, fifth, and sixth embodiment;

[0046] Fig. 1shows a schematic cross-sectional view through a tread 10, which is known from the prior art. This tread 10 has an upper side 12 intended for road contact and an underside 14 intended for connection to other components of a vehicle tire. The tread 10 consists entirely of a central element, with the base 16 extending on the underside 14 and the cover layer 18 extending on the upper side 12. As is customary in the prior art, a material projection, which, like the base 16, consists of a first rubber material, extends through the cover layer 18 to the surface on the upper side 12 of the tread 10 and thus functions as a CCB.

[0047] Fig. 2 shows three schematic cross-sectional views of treads 10 according to the invention, in various preferred embodiments. In comparison with the prior art according to Fig. 1In addition to the central element consisting of the base 16 and the cover layer 18, the treads 10 shown also comprise a first flank element 20 and a second flank element 22, which in the examples shown are each of the same design and, like the respective central element consisting of the base 16 and the cover layer 18, have a trapezoidal basic shape in cross-section, wherein the dimensions and the arrangement of the elements are different in each of the three embodiments shown.

[0048] The image below shows the Fig. 2The recess indicated, which extends through the second flank element 22, the cover layer 18 and at least partially into the base 16, serves to visualize a profile which can be incorporated into the upper side 12 of the tread 10 and illustrates that a corresponding profiling, which extends through several of the elements, is advantageously possible in treads 10 according to the invention, without risking the advantageous conductivity properties.

[0049] Fig. 3shows three further schematic cross-sectional representations of tread strips 10 according to the invention in preferred embodiments. The upper of the illustrated tread strips 10 comprises a first flank element 20 and a second flank element 22, each of which has an angular profile with an angle of approximately 140° in cross-section, and which are arranged on the sides of the central element such that the third and fourth rubber materials lie not only on the underside 14, but also on the upper side 12. The third and fourth rubber materials have a comparatively large contact area with the road surface on the upper side, whereby electrostatic charging can be prevented particularly efficiently.

[0050] In the lower two illustrations of tread strips 10 according to the invention, the first flank element 20 and the second flank element 22 are also designed as an angle profile with respect to the third rubber material and the fourth rubber material, but with an angle of approximately 90°. In contrast to the upper embodiment of the Fig. 3 The contact line between the central element and the flank elements runs essentially vertically along the edge area of ​​the central element. The connection to the central element is made via the sides of the flank elements facing away from the angle, so that the angle profiles extend away from the central element. In contrast to the above embodiment of the Fig. 3A fifth rubber material is arranged in the resulting recesses on the sides of the tread, completing the desired profile geometry. This advantageously makes it possible to minimize the influence of the third or fourth rubber material on the driving characteristics without adversely affecting the favorable effect on the electrical conductivity of the tread 10. Furthermore, the selection of the fifth rubber material also makes it possible to realize particularly advantageous properties of the tread 10 transversely to the circumferential direction, since the side regions formed by the fifth rubber material can, for example, be designed to be particularly flexible or particularly rigid.

[0051] The lower illustration in the Fig. 3shows a particularly preferred embodiment of the tread 10 according to the invention, in which the base 16 comprises four separate and equidistantly spaced partial layers 24a, 24b, 24c, 24d, each of which is connected to the cover layer 18 and lies with a surface on the underside 14 of the tread 10. This embodiment advantageously allows a particularly significant reduction in the proportion of the first rubber material or the base 16, so that it is advantageously possible to obtain a tread 10 with particularly favorable driving characteristics.

[0052] In the Fig. 2 and 3In the exemplary embodiments of the invention shown, the third rubber material of the first flank element 20 and the fourth rubber material of the second flank element 22 are each identical and have a specific resistance of 10 8 < Ω m at 25 °C. The cover layer 18, however, consists of a second rubber material which has a specific resistance of more than 10 11 < Ω m at 25 °C.

[0053] All of the rubber materials used can be produced by vulcanization of vulcanizable rubber mixtures, wherein for the production of the first rubber material, ie the rubber material for the base, preferably 30 phr or more of natural rubber and at least 2 phr of adhesive resins are used, whereas in the examples shown the high conductivity of the rubber materials used in the flank elements was achieved by the use of carbon black.

[0054] All of the treads 10 according to the invention shown can advantageously be produced by coextrusion of the corresponding vulcanizable rubber mixtures with an extruder, wherein the adjacent elements and layers are connected in the contact area by a material bond which was essentially produced by covulcanization of the vulcanizable rubber mixtures. List of reference symbols

[0055] 10Tread 12Topside 14Bottomside 16Base 18Cover layer 20First flank element 22Second flank element 24a-dPartial layers

Claims

1. Tread (10) for use in vehicle tyres, having a top side (12) intended for contact with the driving surface and a bottom side (14) intended for connecting to other components of a vehicle tyre, comprising: a) a central element, comprising: i) a base ply (16), comprising a first rubber material, wherein a surface of the base ply (16) is arranged on the underside (14) of the tread (10), ii) a top ply (18), which is connected to the base ply (16), comprising a second rubber material, wherein a surface of the top ply (18) is arranged on the top side (12) of the tread (10), and b) a first flank element (20), comprising a third rubber material, and a second flank element (22), comprising a fourth rubber material, wherein the first flank element (20) and the second flank element (22) are arranged on opposite sides of the central element, and wherein the third rubber material and the fourth rubber material have a specific resistance of 1010 Ω m or less at 25 °C, characterized in that the third rubber material and the fourth rubber material extend on the sides of the central element from the bottom side (14) of the tread (10) to the top side (12) of the tread (10), wherein the central element consists of the base ply (16) and the top ply (18), wherein the proportion by mass of the third rubber material in the first flank element (20) is 90 % or more, based on the mass of the first flank element (20), and wherein the proportion by mass of the fourth rubber material in the second flank element (22) is 90 % or more, based on the mass of the second flank element (22), or wherein the first flank element (20) and the second flank element (22) comprise at least a fifth rubber material, wherein the fifth rubber material is arranged on that side of the flank element which faces away from the central element.

2. Tread (10) according to Claim 1, wherein the third rubber material and the fourth rubber material have a specific resistance of 109 Ω m or less, preferably of 108 Ω m or less, particularly preferably of 107 Ω m or less at 25 °C.

3. Tread (10) according to either of Claims 1 or 2, wherein the third rubber material and the fourth rubber material are identical.

4. Tread (10) according to any one of Claims 1 to 3, wherein the first flank element (20) and / or the second flank element (22), preferably both flank elements, have a trapezoidal cross section, wherein the longer base side of the trapezoid is preferably located on the bottom side (14) of the tread (10).

5. Tread (10) according to any one of Claims 1 to 4, wherein the central element has a trapezoidal cross section, wherein the longer base side of the trapezoid is preferably located on the top side (12) of the tread (10).

6. Tread (10) according to any one of Claims 1 to 5, wherein the proportion by mass of the third rubber material in the first flank element (20) is 95 % or more, preferably 99 % or more, particularly preferably 99.5 % or more, based on the mass of the first flank element (20), and / or wherein the proportion by mass of the fourth rubber material in the second flank element (22) is 95 % or more, preferably 99 % or more, particularly preferably 99.5 % or more, based on the mass of the second flank element (22).

7. Tread (10) according to any one of Claims 1 to 5, wherein the fifth rubber material is located on the top side (12) of the tread (10), wherein the fifth rubber material is preferably not located on the bottom side (14) of the tread (10), wherein the fifth rubber material and the second rubber material are particularly preferably identical.

8. Tread (10) according to any one of Claims 1 to 7, wherein the first flank element (20) and / or the second flank element (22) in cross section have an angular profile, preferably with an angle of 90° or more, such that the third rubber material and / or the fourth rubber material are located on the sides of the central element and on the top side (12) of the tread (10), wherein the proportion of the top side (12) of the tread (10) that is formed by the third rubber material and / or the fourth rubber material, is preferably in each case in the range of 5 to 30%, preferably in the range of 10 to 20%.

9. Tread (10) according to any one of Claims 1 to 8, wherein the base ply (16) comprises two or more, preferably three or more, particularly preferably four or more, separate and spaced apart, preferably equidistantly spaced apart, partial plies (24a-d), wherein all of the partial plies are connected to the top ply (18), wherein all of the partial plies are located with a surface on the bottom side (14) of the tread (10).

10. Vehicle tyre, in particular pneumatic vehicle tyre, comprising a tread (10) according to one of Claims 1 to 9 as the tread (10).