Method for producing a vehicle tire and vehicle tire

Abstract

The invention relates to a method for producing a pneumatic vehicle tire, comprising the production of a pneumatic vehicle tire green body (10) comprising one or more belt ply green bodies (14a, 14b) comprising one or more first reinforcements embedded in a first vulcanizable rubber mixture, wherein the first reinforcements are selected from the group consisting of metallic reinforcements, wherein the pneumatic vehicle tire green body (10) comprises at least one belt edge protection green body (18) comprising a second vulcanizable rubber mixture, wherein the belt edge protection green body (18) is arranged such that the belt edge protection green body (18) is arranged in the radial direction at least partially below a belt ply green body (14a, 14b) and at least partially above a belt ply green body (14a, 14b), wherein the combined mass fraction of cationic cobalt in the first vulcanizable rubber mixture is 0,03 phr or more, wherein the second vulcanizable rubber mixture comprises less than 0.01 phr of cobalt-containing compounds, wherein the first vulcanizable rubber mixture and the second vulcanizable rubber mixture comprise sulfur, wherein the mass fraction of sulfur in the first vulcanizable rubber mixture is greater than in the second vulcanizable rubber mixture, based on the mass of the respective vulcanizable rubber mixture.

Description

[0001] The invention relates to a method for producing a pneumatic vehicle tire and a pneumatic vehicle tire produced thereby.

[0002] Modern pneumatic vehicle tires are regularly exposed to severe mechanical stress during use. These mechanical stresses can lead to defects, particularly in critical areas where the individual components of the pneumatic vehicle tire meet. In the worst case, this can result in irreparable damage to the pneumatic vehicle tire and a reduction in driving safety.

[0003] One component of modern pneumatic vehicle tires which is often exposed to particularly strong mechanical loads in practice is the belt layers installed in the pneumatic vehicle tire, which consist of reinforcements embedded in a rubber material and are often susceptible to mechanically induced defects, particularly at their edges.

[0004] To solve this problem, the use of belt wraps is known from the prior art. These wraps are wrapped around one or more of the belt layers of the pneumatic vehicle tire in the edge area, thus providing additional coverage of the inserted belt layer. Alternatively, so-called inserts can be used as belt edge protection, which are placed in the edge area between two belt layers of the pneumatic vehicle tire. These design measures serve in particular to protect the edge areas of the belt and to fix the belt in the pneumatic vehicle tire, thus having a correspondingly beneficial effect on the overall durability of the pneumatic vehicle tire.

[0005] To ensure a high bond strength between the belt layers and the belt edge protector, the state-of-the-art rubber compound for the belt edge protector is regularly used as the same rubber compound that is also used in the belt layers. This approach, used in the state of the art, is also established because the rubber material used in the belt layers to rubberize the reinforcement members, or rather the vulcanizable rubber compound underlying this rubber material, is readily available during the production of the belt package, as it is required for the belt layers anyway.

[0006] In the vast majority of cases, the reinforcements of the belt layers are metallic reinforcements, such as steel cords. The rubber materials used to rubberize the metallic reinforcements include cobalt compounds, which allow for better adhesion of the rubber to the metallic reinforcements.

[0007] In addition to the requirement for high durability of pneumatic vehicle tires, there is also a need in the field of technology for pneumatic vehicle tires with the lowest possible rolling resistance, especially since these have a beneficial influence on the fuel consumption of a vehicle equipped with pneumatic vehicle tires.

[0008] The inventors of the present invention have discovered, in the course of their own development work, that the belt edges and the shoulder design of pneumatic vehicle tires have a significant influence on the overall performance in terms of rolling resistance. In this respect, the inventors have found that belt edge protection, which is generally advantageous from a durability perspective, often has a negative impact on rolling resistance properties.

[0009] Thus, with regard to the use and design of belt edge protection in pneumatic vehicle tires, there is a conflict of objectives between advantageous durability and favorable rolling resistance.

[0010] It was the primary object of the present invention to eliminate or at least reduce the disadvantages of the prior art.

[0011] In particular, the object of the present invention was to provide a method for producing a pneumatic vehicle tire and a corresponding pneumatic vehicle tire, with which particularly durable and, at the same time, as low rolling resistance as possible can be obtained, which resolves the related conflict of objectives in a particularly advantageous manner. It was desirable that the pneumatic vehicle tires to be specified should, in principle, be manufacturable as far as possible using devices and materials that are also used in conventional manufacturing processes for pneumatic vehicle tires.

[0012] Furthermore, it was an object of the present invention that the solution found should be as easy as possible to apply to a variety of existing tire designs and ideally without the need for extensive design changes.

[0013] The inventors of the present invention have now found that the objects described above can surprisingly be achieved by deviating from the existing prejudice that the rubber mixture that is also used in the rubber coating of the strength members of the belt layers should be used for the belt edge protection, and instead a mixture is used for the belt edge protection which - unlike the rubber coating of the belt layers - is largely cobalt-free if the corresponding mixture is simultaneously carried out with a lower sulfur content, as defined in the claims.

[0014] Surprisingly, advantageous pneumatic vehicle tires can be obtained in this way which have a belt edge protection which has an advantageous bond strength with the contacted belt layers and at the same time can be advantageously designed with a lower rolling resistance, so that the conflict of objectives existing in this regard is solved particularly advantageously.

[0015] The above-mentioned objects are accordingly 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.

[0016] 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 therefore very particularly preferred. Likewise preferred are embodiments in which a feature of an 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 pneumatic vehicle tires result from the features of preferred methods.

[0017] To the extent that both specific amounts or proportions of this mixture component and preferred embodiments of the mixture component are disclosed below for a mixture component, for example for diene rubbers or the Co-containing compounds, the specific amounts or proportions of the preferably configured mixture components are also disclosed in particular. Furthermore, it is disclosed that, with the corresponding specific total amounts or total proportions of the mixture components, at least some of the mixture components can be preferably configured and, in particular, that preferably configured mixture components can in turn be present in the specific amounts or proportions within the specific total amounts or total proportions.

[0018] The invention particularly relates to a method for producing a pneumatic vehicle tire, comprising the production of a pneumatic vehicle tire blank, comprising the method steps: a) manufacturing or providing a green tyre carcass, b) arranging one or more belt ply blanks, comprising one or more first reinforcements embedded in a first vulcanizable rubber mixture, radially outwardly of the tire carcass blank, wherein the first reinforcements are selected from the group consisting of metallic reinforcements, and c) Attaching a tread blank radially outward to the belt ply blank, and the procedural step: d) Vulcanising the pneumatic vehicle tyre blank to obtain the pneumatic vehicle tyre, wherein the pneumatic vehicle tire blank comprises at least one belt edge protection blank, wherein the belt edge protection blank comprises a second vulcanizable rubber mixture, wherein the belt edge protection blank is arranged such that the belt edge protection blank is arranged in the radial direction at least partially below a belt layer blank and at least partially above a belt layer blank, wherein the first vulcanizable rubber mixture comprises one or more cobalt-containing compounds, wherein the combined mass fraction of cationic cobalt in the first vulcanizable rubber mixture is 0.03 phr or more, based on the mass of the first vulcanizable rubber mixture, wherein the second vulcanizable rubber mixture comprises less than 0.01 phr of cobalt-containing compounds, based on the mass of the second vulcanizable rubber mixture, wherein the first vulcanizable rubber mixture and the second vulcanizable rubber mixture comprise sulfur, wherein the mass fraction of sulfur in the first vulcanizable rubber mixture is greater than in the second vulcanizable rubber mixture, based on the mass of the respective vulcanizable rubber mixture.

[0019] Methods for producing pneumatic vehicle tires are known to those skilled in the art. The method according to the invention can preferably be carried out on a tire building drum. Corresponding devices are known to those skilled in the art and are available from many vehicle tire manufacturers. Such tire building drums are usually rotatable and can be expanded in sections. The use of a tire building drum usually allows for particularly efficient process control.

[0020] In the production of vehicle tires, unvulcanized pneumatic vehicle tire blanks are usually initially produced, each of which comprises an unvulcanized, vulcanizable rubber mixture in the individual components. Such vulcanizable rubber mixtures are generally known to those skilled in the art and are usually based on diene rubbers. Examples include vulcanizable rubber mixtures wherein the vulcanizable rubber mixture comprises at least one diene rubber, wherein the one or more diene rubbers are selected from the group consisting of natural polyisoprene (NR), synthetic polyisoprene (IR), butadiene rubber (BR), solution-polymerized styrene-butadiene rubber (SSBR), and emulsion-polymerized styrene-butadiene rubber (ESBR). Corresponding diene rubbers are also particularly preferred for the first and second vulcanizable rubber mixtures.

[0021] Insofar as mass fractions are specified below for components of vulcanizable rubber compounds, for example for the Co-containing compounds, these are specified in accordance with industry practice as combined mass fractions of one or more components, thereby expressing that the mass fraction of the correspondingly formed components taken together meets the corresponding criteria. The phr (parts per hundred parts of rubber by weight) specification used here is the quantity specification commonly used in the rubber industry for compound formulations, which specifies the mass fractions of the components in the rubber compound relative to the mass of the high-molecular-weight rubbers (weight-average molar mass Mw according to GPC greater than 60,000 g / mol) present in the rubber compound, whereby the combined mass fraction of the high-molecular-weight rubbers in the rubber compound corresponds to 100 phr.

[0022] The resulting pneumatic vehicle tire blank is then converted into a pneumatic vehicle tire by vulcanization, with rubber materials being obtained from the vulcanizable rubber mixtures. The pneumatic vehicle tire blank obtained in the process according to the invention is vulcanized for this purpose in the usual manner. In this respect, a process according to the invention is preferred, wherein the vulcanization takes place at a temperature in the range of 120 to 200°C, preferably in the range of 130 to 180°C. Additionally or alternatively, a process according to the invention is preferred, wherein the vulcanization takes place in a vulcanization mold.

[0023] Those skilled in the art will understand that the pneumatic vehicle tire blank produced in the process according to the invention and the pneumatic vehicle tire producible therefrom by vulcanization are inseparably connected to one another. The designation of the components within the scope of the present invention is chosen such that an "element blank" comprising a vulcanizable rubber mixture becomes, through vulcanization, precisely that "element" comprising a rubber material obtained by vulcanization from the vulcanizable rubber mixture. The pneumatic vehicle tire according to the invention, which is obtained in process step d), accordingly comprises a first rubber material produced from the first vulcanizable rubber mixture and a second rubber material produced from the second vulcanizable rubber mixture.

[0024] The invention thus also relates to a pneumatic vehicle tire, produced or producible by the method according to the invention, comprising i) a tyre carcass, ii) one or more belt plies located radially outward relative to the tire carcass, comprising one or more first reinforcements embedded in a first rubber material, wherein the first reinforcements are selected from the group consisting of metallic reinforcements, iii) at least one belt edge protector comprising a second rubber material, wherein the belt edge protector is arranged in the radial direction partly below a belt layer and partly above a belt layer, iv) a tread located radially outward relative to the tyre carcass and the belt ply, and wherein the first rubber material is producible by vulcanizing a first vulcanizable rubber mixture, wherein the first vulcanizable rubber mixture comprises one or more cobalt-containing compounds, wherein the combined mass fraction of cationic cobalt in the first vulcanizable rubber mixture is 0.03 phr or more, based on the mass of the first vulcanizable rubber mixture, wherein the second rubber material is producible by vulcanizing a second vulcanizable rubber mixture, wherein the second vulcanizable rubber mixture comprises less than 0.01 phr of cobalt-containing compounds, based on the mass of the second vulcanizable rubber mixture, wherein the first vulcanizable rubber mixture and the second vulcanizable rubber mixture comprise sulfur, wherein the mass fraction of sulfur in the first vulcanizable rubber mixture is greater than in the second vulcanizable rubber mixture, based on the mass of the respective vulcanizable rubber mixture.

[0025] The present invention is primarily based on a modified chemical composition of the vulcanizable rubber mixture used to form the belt edge protector in the belt edge protector blank. For this reason, it is expedient to define the invention in particular by the manufacturing process.

[0026] However, for an easier understanding of the present invention, it is expedient to first explain the components of the pneumatic vehicle tire produced by the method according to the invention that are necessary for the definition of the present invention.

[0027] The basic structure of pneumatic vehicle tires is known to those skilled in the art. An example of a method according to the invention is a pneumatic vehicle tire that is a passenger car tire or a truck tire.

[0028] In accordance with the usual construction of pneumatic vehicle tires, the pneumatic vehicle tire produced by the method according to the invention also initially comprises a tire carcass. This tire carcass consists of one or more carcass plies in which reinforcements are embedded in a rubber material, also referred to as rubber lining. The tire carcass and the corresponding rubber material are obtained from a green tire carcass by vulcanization in accordance with the usual procedure. In this case, it is a method according to the invention, wherein the green tire carcass comprises one or more third reinforcements embedded in a third vulcanizable rubber mixture. Based on the vulcanized product, this is a pneumatic vehicle tire according to the invention, wherein the tire carcass comprises one or more third reinforcements embedded in a third rubber material.A method according to the invention or a pneumatic vehicle tire according to the invention is preferred, wherein the third reinforcements are selected from the group consisting of textile reinforcements.

[0029] For the carcass, a rubber compound is usually selected that differs from the rubber coating of the reinforcements in the belt layers. Accordingly, a method according to the invention is particularly relevant in practice, wherein the third vulcanizable rubber compound differs from the first vulcanizable rubber compound and the second vulcanizable rubber compound. With regard to the vulcanized product, this is, in particular, a pneumatic vehicle tire according to the invention, wherein the third rubber material differs from the first rubber material and the second rubber material.

[0030] At least one belt ply is arranged radially above the tire carcass, i.e. further outwards in the radial direction. The belt ply also comprises reinforcements embedded in a rubber material, wherein the reinforcements are metallic reinforcements according to the invention. While the reinforcements of the tire carcass often run essentially along the radial direction, the reinforcements of the belt ply usually run more in the circumferential direction, with which they preferably enclose an angle in the range of 18° to 45°. The vulcanizable rubber mixture of the belt ply blanks, the rubber material that can be produced therefrom and the corresponding metallic reinforcements are identified in the context of the present invention by the adjective “first”. The person skilled in the art will understand that when there are two or more belt plies orFor belt layer blanks, the first vulcanizable rubber mixture, the first rubber material producible therefrom, and the corresponding first reinforcements do not have to be identical for all layers, although this is preferred. It can be seen as an advantage of the invention that, in principle, materials known from the prior art can be used for the first reinforcements and their rubber coating, in particular a cobalt-containing rubber coating, as explained further below.

[0031] In principle, a method according to the invention is first preferred, wherein in method step b) two or more belt ply blanks are arranged one above the other in the radial direction, wherein the two or more belt ply blanks preferably comprise the same first reinforcements and / or the same first vulcanizable rubber mixture. Accordingly, with respect to the vulcanized product, a pneumatic vehicle tire according to the invention is preferred, wherein the pneumatic vehicle tire comprises two or more belt plies arranged one above the other in the radial direction, wherein the two or more belt plies preferably comprise the same first reinforcements and / or the same first rubber material.

[0032] With regard to the selection of the reinforcements, a method according to the invention or a pneumatic vehicle tire according to the invention is preferred, wherein the first reinforcements are selected from the group consisting of iron cords and steel cords, preferably steel cords.

[0033] Arranged radially above both the belt ply and the tire carcass is the tread intended for contact with the road surface, which generally forms the outermost part of the pneumatic vehicle tire in the radial direction. The tread and the underlying tread blank can advantageously be designed relatively freely within the scope of the present invention, particularly with regard to the tread profile.

[0034] Before discussing the belt edge protection measures and the specific coordination of the vulcanizable rubber compounds below, it is useful to clarify that other conventional components can also be provided in pneumatic vehicle tires according to the invention, in particular a wound bandage. In this case, the process according to the invention additionally comprises the process step between process steps b) and c): e) Applying a wound bandage blank located radially outward relative to the belt ply blank, comprising at least one fourth reinforcement embedded in a fourth vulcanizable rubber mixture. Based on the vulcanized product, this is a pneumatic vehicle tire according to the invention, additionally comprising a wound bandage between the belt ply and the tread, comprising at least one fourth reinforcement embedded in a fourth rubber material.

[0035] Also exemplary is a method according to the invention, wherein the vehicle pneumatic tire blank additionally comprises: v) two bead element blanks each arranged in a bead area of ​​the tire carcass green, and / or vi) two sidewall blanks arranged on the sides of the green pneumatic vehicle tyre, and / or vii) a green tire inner layer arranged on the radially inner side of the green tire carcass.

[0036] Analogously, a pneumatic vehicle tire according to the invention is exemplary, wherein the pneumatic vehicle tire additionally comprises: v) two bead elements each arranged in a bead area of ​​the tyre carcass, and / or (vi) two sidewall components arranged on the sides of the pneumatic vehicle tyre, and / or vii) an inner tyre layer arranged on the radially inner side of the tyre carcass.

[0037] A central feature of pneumatic vehicle tires according to the invention is the fact that they comprise at least one element that serves to protect the belt edges and is referred to in the context of the present invention as a belt edge protector. In keeping with the name, the belt edge protector or belt edge protector blank is located in the region of the lateral edge of the belt plies and serves to protect them.

[0038] Even if it would theoretically be conceivable to apply the belt edge protection blank only on the tire building drum—quasi-subsequently—in the area of ​​the belt edges, it is particularly preferred to provide the belt plies to be installed with the corresponding belt edge protection blank before the corresponding belt package is applied. Accordingly, a method according to the invention is preferred, wherein the belt edge protection blank is attached to the one or more belt ply blanks before the belt ply blanks are arranged in method step b), and / or wherein the belt ply blank(s) and the belt edge protection blank(s) are arranged as a common assembly during the production of the pneumatic vehicle tire blank.

[0039] According to the invention, the belt edge protection blank is arranged such that the belt edge protection blank is arranged radially at least partially below a belt layer blank and at least partially above a belt layer blank. The belt layer blank relative to which the arrangement takes place does not have to be the same belt layer blank.

[0040] If two or more belt layer blanks are present, the belt edge protection blank can, for example, be arranged between the belt layer blanks so that it contacts the radially outer belt layer blank radially inward and the radially inner belt layer blank radially outward. In this case, experts also refer to it as an "insert."

[0041] Alternatively, the belt edge protection blank can be designed as a so-called "wrap", in which a material layer can be placed around the edge of one or more belt layers. In this case, the belt edge protection blank can, for example, contact the same belt layer radially inward and radially outward, whereby it is possible that in this case another belt layer is also contacted radially inward or radially outward. Alternatively, the "wrap" can also be wrapped around two or more belt layers so that it contacts a first belt layer radially inward and a second belt layer radially outward. In the inventors' opinion, the use of a "wrap" is generally preferred for more applications due to its particularly advantageous effect on the durability of the pneumatic vehicle tire.

[0042] In light of the above, a method according to the invention is preferred, wherein the pneumatic vehicle tire blank comprises two or more belt ply blanks, wherein the belt edge protection blank is a belt edge insertion blank, wherein the belt edge insertion blank is arranged between two belt ply blanks. A method according to the invention is particularly preferred, wherein the belt edge insertion blank is arranged such that, in the radial direction, the belt edge insertion blank is arranged below the respective belt ply blanks with respect to a portion of the belt ply blanks and above the respective belt ply blanks with respect to a portion of the belt ply blanks.In addition or alternatively, a method according to the invention is particularly preferred, wherein the belt edge insertion blank is arranged such that the belt edge insertion blank contacts one of the belt layer blanks, preferably the belt layer blank which is furthest outside in the radial direction, in the radial direction inside and one of the belt layer blanks, preferably the belt layer blank which is furthest inside in the radial direction, in the radial direction outside.

[0043] With regard to the vulcanized product, a pneumatic vehicle tire is therefore preferred, wherein the pneumatic vehicle tire comprises two or more belt plies, wherein the belt edge protection is a belt edge insert, wherein the belt edge insert is arranged between two belt plies. A pneumatic vehicle tire is particularly preferred, wherein the belt edge insert is arranged such that the belt edge insert is arranged below the respective belt ply in the radial direction with respect to some of the belt plies and above the respective belt ply with respect to some of the belt plies. Additionally or alternatively, a pneumatic vehicle tire is also particularly preferred, wherein the belt edge insert contacts one of the belt plies, preferably the belt ply furthest outward in the radial direction, in the radial direction inward and one of the belt plies, preferably the belt ply furthest in the radial direction, in the radial direction outward.

[0044] Compared to the use of inserts, a method according to the invention is particularly preferred, wherein the belt edge protection blank is a belt turn-up blank. Due to the high durability that can be achieved thereby, a method according to the invention is particularly preferred, wherein the belt turn-up blank is arranged such that the belt turn-up blank is arranged partially below and partially above the belt layer blank in the radial direction with respect to one of the belt layer blanks, preferably with respect to at least two of the belt layer blanks, particularly preferably with respect to all of the belt layer blanks.Additionally or alternatively, a method according to the invention is also particularly preferred, wherein the belt turn-up blank is arranged such that the belt turn-up blank contacts one of the belt layer blanks, preferably the belt layer blank furthest inside in the radial direction, and one of the belt layer blanks, preferably the belt layer blank furthest outside in the radial direction, in the radial direction. In turn, additionally or alternatively, a method according to the invention is also particularly preferred, wherein the belt turn-up blank is formed by a turned-up layer-like material.

[0045] With regard to the vulcanized product, a pneumatic vehicle tire is therefore preferred, wherein the belt edge protection is a belt turn-up. A pneumatic vehicle tire is particularly preferred, wherein the belt turn-up is arranged partly below and partly above the belt layer in the radial direction with respect to one of the belt layers, preferably with respect to at least two of the belt layers, particularly preferably with respect to all of the belt layers. Additionally or alternatively, a pneumatic vehicle tire is particularly preferred, wherein the belt turn-up contacts one of the belt layers, preferably the belt layer furthest inside in the radial direction, and one of the belt layers, preferably the belt layer furthest outside in the radial direction, is particularly preferred.

[0046] In addition or alternatively, a pneumatic vehicle tire according to the invention is particularly preferred, wherein the belt turn-up is formed by a deformed layer-shaped element.

[0047] The person skilled in the art will understand that the belt layers running circumferentially around the pneumatic vehicle tire have an edge on both sides in the axial direction that also runs around the pneumatic vehicle tire.

[0048] According to the inventors' assessment, improvements in the durability of pneumatic vehicle tires can in principle be achieved even if only one of the edges is provided with a belt edge protector. For the majority of embodiments, however, it is preferred to provide belt edge protectors on both sides, thus optimizing durability by protecting the belt edges on both sides. Accordingly, a method according to the invention is preferred, wherein the pneumatic vehicle tire blank comprises two or more, preferably exactly two, belt edge protector blanks, preferably on opposite sides of the belt layer blank(s) in the axial direction.With regard to the vulcanized product, a pneumatic vehicle tire according to the invention is preferred, wherein the pneumatic vehicle tire comprises two or more, preferably exactly two, belt edge protectors, wherein the belt edge protectors are preferably arranged in the axial direction on opposite sides of the belt layer(s).

[0049] If two or more belt edge protectors are provided, it is preferable to design them as similarly as possible in order to simplify production and reduce the need for different semi-finished products. Accordingly, a method according to the invention is preferred, wherein the two or more belt edge protector blanks comprise the same second vulcanizable rubber mixture, and / or wherein the two or more belt edge protector blanks are of substantially similar design. With respect to the vulcanized product, a pneumatic vehicle tire according to the invention is preferred, wherein the two or more belt edge protectors comprise the same second rubber material, and / or wherein the two or more belt edge protectors are of substantially similar design.

[0050] In this respect, the person skilled in the art will understand that, in order to comprehensively protect the edges of the belt layers surrounding the pneumatic vehicle tire and in the sense of rolling properties that are as uniform as possible, it is preferred for essentially all embodiments that the belt edge protection blank(s) or belt edge protections also extend essentially over the entire circumference of the pneumatic vehicle tire.

[0051] The inventors have recognized that it is particularly advantageous for rolling resistance if the belt edge protection blanks or belt edge protectors do not comprise any reinforcements. In the opinion of the inventors, in cases where reinforcements are to be used, it is preferable to use textile reinforcements instead of metallic reinforcements. This is particularly reinforced by the fact that the second vulcanizable rubber mixture bonds significantly less well to metallic reinforcements due to the low cobalt content. A method according to the invention is thus conceivable, wherein the belt edge protection blank comprises one or more second reinforcements embedded in the second vulcanizable rubber mixture, wherein the second reinforcements are selected from the group consisting of textile reinforcements.A method according to the invention is preferred, wherein the belt turn-up blank does not comprise any metallic reinforcements. With respect to the vulcanized product, a pneumatic vehicle tire according to the invention is conceivable, wherein the belt edge protection comprises one or more second reinforcements embedded in the second rubber material, wherein the second reinforcements are selected from the group consisting of textile reinforcements. A pneumatic vehicle tire according to the invention is preferred, wherein the belt edge protection does not comprise any metallic reinforcements.

[0052] However, preference is given to the greatest possible omission of reinforcements and thus to a method according to the invention, wherein the belt edge protection blank consists of the second vulcanizable rubber mixture to a mass fraction of 95% or more, preferably 98% or more, particularly preferably 99% or more, very particularly preferably essentially 100%. Based on the vulcanized product, a pneumatic vehicle tire according to the invention is preferred, wherein the belt edge protection consists of the second rubber material to a mass fraction of 95% or more, preferably 98% or more, particularly preferably 99% or more, very particularly preferably essentially 100%.

[0053] With regard to the positioning of the belt edge protection, the inventors propose that, in the case of an "insert," it should extend sufficiently far between the belt layers, or, in the case of a "wrap," it should be positioned significantly above or below the belt layer. This design can be effectively evaluated in the radial section, i.e., in the plane orthogonal to the circumferential direction.Accordingly, a method according to the invention is preferred, wherein the belt edge protection blank is arranged such that 10% or more, preferably 20% or more, particularly preferably 30% or more, of the belt edge protection blank is arranged in the radial direction above a belt layer blank, based on the cross-sectional area of ​​the belt edge protection blank in the plane orthogonal to the circumferential direction, and / or wherein the belt edge protection blank is arranged such that 10% or more, preferably 20% or more, particularly preferably 30% or more, of the belt edge protection blank is arranged in the radial direction below a belt layer blank, based on the cross-sectional area of ​​the belt edge protection blank in the plane orthogonal to the circumferential direction.With respect to the vulcanized product, a pneumatic vehicle tire according to the invention is complementarily preferred, wherein the belt edge protection is arranged such that 10% or more, preferably 20% or more, particularly preferably 30% or more, of the belt edge protection is arranged in the radial direction above a belt layer, based on the cross-sectional area of ​​the belt edge protection in the plane orthogonal to the circumferential direction, and / or wherein the belt edge protection is arranged such that 10% or more, preferably 20% or more, particularly preferably 30% or more, of the belt edge protection is arranged in the radial direction below a belt layer, based on the cross-sectional area of ​​the belt edge protection in the plane orthogonal to the circumferential direction.

[0054] In order to advantageously minimize the weight, the inventors consider it expedient not to make the belt edge protector too large, but to design it in such a way that the protective function for the belt edge is the main focus.

[0055] A method according to the invention is preferred, wherein the belt edge protection blank is arranged such that the belt edge protection blank is arranged exclusively outside the central region of the one or more belt layer blanks in the radial direction below or above the one or more belt layer blanks, wherein the central region comprises in each case the 40%, preferably 60%, particularly preferably 80%, of the belt layer blanks which are centrally located in the axial direction. With regard to the vulcanized product, a pneumatic vehicle tire according to the invention is complementarily preferred, wherein the belt edge protection is arranged such that the belt edge protection is arranged exclusively outside the central region of the one or more belt layers in the radial direction below or aboveis arranged above the one or more belt layers, wherein the central region comprises the 40%, preferably 60%, particularly preferably 80%, of the belt layers lying centrally in the axial direction.

[0056] An essential aspect of the present invention is that it relates to belt plies with metallic reinforcements, in the rubber coating of which cobalt-containing compounds are used, which act in particular as adhesion promoters and, according to the inventors' assessment, have a noticeable influence on the physicochemical properties of the vulcanizable rubber mixture or the resulting rubber materials. Preferred is a process according to the invention or a pneumatic vehicle tire according to the invention, wherein the cobalt-containing compounds are selected from the group consisting of cobalt salts, preferably selected from the group consisting of cobalt nathenate, cobalt stearate, and cobalt borate alkanoates, for example cobalt borate decanoate, preferably selected from the group consisting of cobalt stearate and cobalt borate alkanoates.

[0057] For many applications, it is advantageous to set higher contents of cobalt-containing compounds to ensure an advantageously high bond strength between the metallic reinforcements and the rubber coating in the belt layers. In accordance with standard practice in the industry, the cobalt content is stated based on the mass of cationic cobalt, so that the influence of different anions can be eliminated. In this case, a method according to the invention or a pneumatic vehicle tire according to the invention is preferred, wherein the combined mass fraction of cationic cobalt in the first vulcanizable rubber mixture is 0.04 phr or more, preferably 0.05 phr or more, particularly preferably 0.06 phr or more, based on the mass of the first vulcanizable rubber mixture.Additionally or alternatively, a method according to the invention or a pneumatic vehicle tire according to the invention is also preferred, wherein the combined mass fraction of cationic cobalt in the first vulcanizable rubber mixture is in the range from 0.03 to 1 phr, preferably in the range from 0.04 to 0.08 phr, particularly preferably in the range from 0.05 to 0.5 phr, based on the mass of the first vulcanizable rubber mixture.

[0058] An essential aspect of the present invention is that, in contrast to the usual procedure in the prior art for belt edge protection, the use of cobalt-containing compounds is avoided as far as possible. Accordingly, a method according to the invention or a pneumatic vehicle tire according to the invention is also preferred, wherein the second vulcanizable rubber mixture comprises less than 0.005 phr, preferably less than 0.003 phr, particularly preferably less than 0.001 phr, of cobalt-containing compounds, based on the mass of the second vulcanizable rubber mixture, wherein the second vulcanizable rubber mixture very particularly preferably comprises no cobalt-containing compounds.

[0059] By avoiding cobalt-containing compounds for the belt edge protector as much as possible, the flexibility in the mixture composition can be advantageously increased, making rubber materials accessible that exhibit more favorable rolling resistance. In the inventors' estimation, it is preferable for the vast majority of embodiments to make use of this option and to design the rubber material of the belt edge protector with advantageous hysteresis behavior. This can be expressed using the loss factor tan δ, which is established in the field of technology and whose value at 70 °C serves as a rolling resistance indicator, with a lower loss factor tan δ (70 °C) indicating lower rolling resistance.The loss factor tan δ at 70 °C is determined from temperature-dependent dynamic mechanical measurements using an Eplexor according to DIN 53513:1990-03 (constant force, 10 % compression, ± 0.2 % strain amplitude, frequency 10 Hz).

[0060] Preference is given to a method according to the invention or a pneumatic vehicle tire according to the invention, wherein the first rubber material at 70 °C has a loss factor tan δ in the range from 0.06 to 0.3, preferably in the range from 0.07 to 0.25, particularly preferably in the range from 0.08 to 0.2, and / or wherein the second rubber material at 70 °C has a loss factor tan δ in the range from 0.01 to 0.12, preferably in the range from 0.02 to 0.1, particularly preferably in the range from 0.03 to 0.09. Additionally or alternatively, preference is given to a method according to the invention or a pneumatic vehicle tire according to the invention, wherein the second rubber material at 70 °C has a lower loss factor tan δ than the first rubber material, wherein the loss factor tan δ is preferably smaller by 0.02 or more, preferably 0.04 or more, particularly preferably 0.06 or more.

[0061] The inventors have recognized that in order to ensure good bond strength between the belt layer and the low-cobalt belt edge protection, it is necessary to reduce the proportion of sulfur compared to the rubber coating of the belt layers.

[0062] For the rubber coating of the belt layers, a method according to the invention or a pneumatic vehicle tire according to the invention is preferred, wherein the first vulcanizable rubber mixture comprises sulfur in a mass fraction of 3 phr or more, preferably of 3.5 phr or more, particularly preferably of 4 phr or more, based on the mass of the first vulcanizable rubber mixture, and / or wherein the first vulcanizable rubber mixture comprises sulfur in a mass fraction in the range from 3 to 8 phr, preferably in the range from 3.5 to 7 phr, particularly preferably in the range from 4 to 6 phr, based on the mass of the first vulcanizable rubber mixture.

[0063] With regard to the belt edge protection, a method according to the invention or a pneumatic vehicle tire according to the invention is preferred, wherein the second vulcanizable rubber mixture comprises sulfur in a mass fraction of 1 phr or more, preferably of 1.5 phr or more, particularly preferably of 2 phr or more, based on the mass of the first vulcanizable rubber mixture, and / or wherein the second vulcanizable rubber mixture comprises sulfur in a mass fraction of 5 phr or less, preferably of 4 phr or less, particularly preferably of 3 phr or less, based on the mass of the second vulcanizable rubber mixture, and / or wherein the second vulcanizable rubber mixture comprises sulfur in a mass fraction in the range from 1 to 5 phr, preferably in the range from 1.5 to 4 phr, particularly preferably in the range from 2 to 3 phr, based on the mass of the second vulcanizable rubber mixture.

[0064] With regard to the difference in the sulfur contents, a method according to the invention or a pneumatic vehicle tire according to the invention is preferred, wherein the mass fraction of sulfur in the first vulcanizable rubber mixture is at least 1.2 times, preferably 1.5 times, greater than in the second vulcanizable rubber mixture.

[0065] The inventors consider it particularly preferable to make the composition of the vulcanizable rubber mixture as uniform as possible, apart from the mass fraction of cobalt-containing compounds or sulfur, particularly with regard to the rubber base, plasticizers, fillers, and other additives, thereby achieving advantageous bond strength in the contact area. Furthermore, relatively similar elastic moduli and thermal expansion coefficients can be achieved, which can reduce stresses in the vehicle tire.Specifically, a method according to the invention or a pneumatic vehicle tire according to the invention is preferred, wherein the first vulcanizable rubber mixture and the second rubber mixture, based on the combined mass of all rubbers in the respective vulcanizable rubber mixture, comprise 80% or more, preferably 90% or more, particularly preferably 95% or more, and most particularly preferably substantially 100%, of the same rubbers, relative to the larger of the two combined mass fractions of all rubbers in the respective vulcanizable rubber mixtures. For this purpose, the lower of the two mass fractions in phr is summed for all rubbers found in both vulcanizable rubber mixtures. Strictly speaking, the value is evaluated relative to the larger of the two combined mass fractions of all rubbers in the respective vulcanizable rubber mixtures.However, since this sum is 100 phr by definition in both cases, no distinction needs to be made between the rubbers—unlike the other components. For clarity, this means that two vulcanizable rubber compounds, which, for example, consist of 70 phr BR and 30 phr NR or 55 phr BR, 35 phr NR, and 10 phr SSBR, contain 55 phr BR and 30 phr NR as the same diene rubbers and accordingly contain 85% ((55 phr + 30 phr) / 100 phr) of the same diene rubbers.

[0066] Additionally or alternatively, a method according to the invention or a pneumatic vehicle tire according to the invention is preferred, wherein the first vulcanizable rubber mixture and the second rubber mixture comprise 80% or more, preferably 90% or more, particularly preferably 95% or more, very particularly preferably substantially 100%, of the same plasticizers based on the combined mass of all plasticizers in the respective vulcanizable rubber mixture, relative to the larger of the two combined mass fractions of all plasticizers of the respective vulcanizable rubber mixtures.

[0067] In turn, additionally or alternatively, a method according to the invention or a pneumatic vehicle tire according to the invention is preferred, wherein the first vulcanizable rubber mixture and the second rubber mixture comprise 80% or more, preferably 90% or more, particularly preferably 95% or more, very particularly preferably substantially 100%, of the same fillers, based on the combined mass of all plasticizers in the respective vulcanizable rubber mixture, relative to the larger of the two combined mass fractions of all fillers of the respective vulcanizable rubber mixtures.

[0068] Also additionally or alternatively preferred is a method according to the invention or a pneumatic vehicle tire according to the invention, wherein the first vulcanizable rubber mixture and the second rubber mixture, based on the combined mass of all further additives which are not diene rubbers, fillers or plasticizers, in the respective vulcanizable rubber mixture comprise 80% or more, preferably 90% or more, particularly preferably 95% or more, of the same further additives, relative to the larger of the two combined mass fractions of all further additives of the respective vulcanizable rubber mixtures.

[0069] Taken together, a method according to the invention or a pneumatic vehicle tire according to the invention is particularly preferred, wherein the first vulcanizable rubber mixture and the second rubber mixture comprise 70% or more, preferably 80% or more, particularly preferably 90% or more, very particularly preferably 95% or more, of the same components, based on the combined mass of all components in the respective vulcanizable rubber mixture, relative to the larger of the two combined mass fractions of all components of the respective vulcanizable rubber mixtures.

[0070] The invention and preferred embodiments of the invention are explained and described in more detail below with reference to the accompanying figures. Fig. 1 a schematic cross-sectional view through a pneumatic vehicle tire blank produced in a method according to the invention in a first embodiment, and Fig. 2 a schematic cross-sectional view through a pneumatic vehicle tire blank produced in a method according to the invention in a second embodiment.

[0071] Fig. 1 and Fig. 2 each show a very schematic cross-sectional view through a pneumatic vehicle tire blank 10 produced in a method according to the invention in various preferred embodiments, wherein for reasons of clarity only one half of the otherwise essentially mirror-symmetrical pneumatic vehicle tire blanks 10 is shown.

[0072] In the examples shown, the pneumatic vehicle tire blank 10 comprises a tire carcass blank 12 in the radial direction on the inside, to which two belt ply blanks 14a, 14b are adjacent on the radial outside.

[0073] The radially inner belt ply blank 14a and the radially outer belt ply blank 14b are designed similarly with regard to the reinforcements and the rubber coating mixture and each comprise a plurality of steel cords embedded in a first vulcanizable rubber mixture as metallic first reinforcements. In the examples shown, the first vulcanizable rubber mixture comprises a cobalt-containing compound, namely, for example, cobalt borate, for example in a combined mass fraction of approximately 0.4 phr based on the mass of the first vulcanizable rubber mixture, from which a first vulcanizable rubber mixture is obtained in which the combined mass fraction of cationic cobalt is approximately 0.09 phr.

[0074] Radially outwardly, i.e. above the belt layer blank 14b, the shown pneumatic vehicle tire blanks 10 each comprise a tread blank 16.

[0075] In both examples shown, the pneumatic vehicle tire blank 10 also includes a belt edge protection blank 18 for protecting the belt layer blanks 14a-b from damage, which extends along the belt edge substantially over the entire circumference of the pneumatic vehicle tire blank 10. In the examples shown, the belt edge protection blank 18 consists of a second vulcanizable rubber mixture that contains essentially no cobalt-containing compounds, i.e., less than 0.001 phr, based on the mass of the second vulcanizable rubber mixture.

[0076] The first and second vulcanizable rubber mixtures each contain sulfur for subsequent vulcanization, the mass fraction of sulfur in the first vulcanizable rubber mixture being approximately 1.5 times greater than in the second vulcanizable rubber mixture, based on the mass of the respective vulcanizable rubber mixture.

[0077] In Fig. 1, the belt ply protection blank 18 is a belt edge insertion blank, with those skilled in the art also referring to such an arrangement as a so-called "insert." The belt ply protection blank 18 is arranged between the lower belt ply blank 14a and the upper belt ply blank 14b such that it contacts the radially outer belt ply blank 14b radially inward and the radially inner belt ply blank 14a radially outward.

[0078] In Fig. 2, the belt ply protection blank 18 is a belt wrap blank formed by a layered material folded around the edge of the lower belt ply blank 14a, whereby the person skilled in the art also refers to such an arrangement as a so-called "wrap." The belt ply protection blank 18 is arranged around the edge of the belt ply blank 14a in such a way that it contacts the latter radially inward and radially outward, as well as the belt ply blank 14b radially inward.

[0079] In both shown embodiments of the Fig. 1 and Fig. 2, the belt edge protection blank 18 is arranged such that it lies exclusively outside the central region of the belt layer blanks 14a-b, that is to say outside the 80% of the belt layer blanks 14a-b which are centrally located in the axial direction.

[0080] By vulcanization, a pneumatic vehicle tire according to the invention can be obtained from each of the thus-constructed pneumatic vehicle tire blanks 10 in a process according to the invention. The second rubber material obtained from the second vulcanizable rubber mixture has a loss factor tan δ at 70°C that is 0.06 lower than the first rubber material obtained from the first vulcanizable rubber mixture. Such a pneumatic vehicle tire has a favorable ratio of rolling resistance to durability. List of reference symbols 10 vehicle pneumatic tire blanks 12 tire carcass blanks 14a-b Belt layer blanks 16 Tread blank 18 Belt edge protection blank

Claims

[1] Method for producing a pneumatic vehicle tire, comprising the production of a pneumatic vehicle tire blank (10), comprising the method steps: a) producing or providing a green tyre carcass (12), b) arranging one or more belt ply blanks (14a, 14b), comprising one or more first reinforcements embedded in a first vulcanizable rubber mixture, radially outwardly of the tire carcass blank (12), wherein the first reinforcements are selected from the group consisting of metallic reinforcements, and c) Attaching a tread blank (16) radially outwardly to the belt ply blank (14a, 14b), as well as the process step: d) vulcanising the pneumatic vehicle tyre blank (10) to obtain the pneumatic vehicle tyre, wherein the pneumatic vehicle tire blank (10) comprises at least one belt edge protection blank (18), wherein the belt edge protection blank (18) comprises a second vulcanizable rubber mixture, wherein the belt edge protection blank (18) is arranged such that the belt edge protection blank (18) is arranged in the radial direction at least partially below a belt layer blank (14a, 14b) and at least partially above a belt layer blank (14a, 14b), wherein the first vulcanizable rubber mixture comprises one or more cobalt-containing compounds, wherein the combined mass fraction of cationic cobalt in the first vulcanizable rubber mixture is 0.03 phr or more, based on the mass of the first vulcanizable rubber mixture, wherein the second vulcanizable rubber mixture comprises less than 0.01 phr of cobalt-containing compounds, based on the mass of the second vulcanizable rubber mixture, wherein the first vulcanizable rubber mixture and the second vulcanizable rubber mixture comprise sulfur, wherein the mass fraction of sulfur in the first vulcanizable rubber mixture is greater than in the second vulcanizable rubber mixture, based on the mass of the respective vulcanizable rubber mixture. [2] The method according to claim 1, wherein the first strength members are selected from the group consisting of iron cords and steel cords. [3] Method according to one of claims 1 or 2, wherein the pneumatic vehicle tire blank (10) comprises two or more belt ply blanks (14a, 14b). [4] Method according to one of claims 1 to 3, wherein the belt edge protection blank (18) is a belt turn-up blank. [5] Method according to claim 3, wherein the belt edge protection blank (18) is a belt edge insertion blank, wherein the belt edge insertion blank is arranged between two belt ply blanks (14a, 14b). [6] The method of any one of claims 1 to 5, wherein the combined mass fraction of cationic cobalt in the first vulcanizable rubber composition is 0.05 phr or more, based on the mass of the first vulcanizable rubber composition. [7] A method according to any one of claims 1 to 6, wherein the first vulcanizable rubber composition comprises sulfur in a mass fraction of 3 phr or more, based on the mass of the first vulcanizable rubber composition. [8] A method according to any one of claims 1 to 7, wherein the second vulcanizable rubber composition comprises sulfur in a mass fraction of 1 phr or more, based on the mass of the second vulcanizable rubber composition. [9] Pneumatic vehicle tyres, manufactured or producible by the method according to one of claims 1 to 8, comprising i) a tyre carcass, ii) one or more belt plies located radially outward relative to the tire carcass, comprising one or more first reinforcements embedded in a first rubber material, wherein the first reinforcements are selected from the group consisting of metallic reinforcements, iii) at least one belt edge protector comprising a second rubber material, wherein the belt edge protector is arranged in the radial direction partly below a belt layer and partly above a belt layer, and iv) a tread located radially outward relative to the tyre carcass and the belt ply, wherein the first rubber material is producible by vulcanizing a first vulcanizable rubber mixture, wherein the first vulcanizable rubber mixture comprises one or more cobalt-containing compounds, wherein the combined mass fraction of cationic cobalt in the first vulcanizable rubber mixture is 0.03 phr or more, based on the mass of the first vulcanizable rubber mixture, wherein the second rubber material is producible by vulcanizing a second vulcanizable rubber mixture, wherein the second vulcanizable rubber mixture comprises less than 0.01 phr of cobalt-containing compounds, based on the mass of the second vulcanizable rubber mixture, wherein the first vulcanizable rubber mixture and the second vulcanizable rubber mixture comprise sulfur, wherein the mass fraction of sulfur in the first vulcanizable rubber mixture is greater than in the second vulcanizable rubber mixture, based on the mass of the respective vulcanizable rubber mixture. [10] Pneumatic vehicle tire according to claim 9, wherein the second rubber material has a lower loss factor tan δ at 70 °C than the first rubber material.

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