Vehicle tire and method for producing a vehicle tire

Abstract

The invention relates to a vehicle tire which is produced or can be produced by vulcanizing a vehicle tire blank (10), wherein the vehicle tire blank (10) comprises: at least one belt layer blank (14a, 14b), which is located further outwards in the radial direction relative to a carcass blank (12), and at least one other outer bandage blank (16) comprising one or more third reinforcements embedded in a vulcanizable rubber mixture. The bandage blank (16) comprises, in the transverse direction, a first edge portion (18), a second edge portion (20), and a central portion (22) provided therebetween; at least some of the third reinforcements in the first edge portion (18) and in the second edge portion (20) are polyester cords partly made of polyester; the polyester cord or cords is / are cords with an AxB structure, A ranging from 300 to 800 dtex, and B ranging from 1 to 3; and the polyester cord or cords has / have a heat shrinkage of 5% or more and a shrinking force ranging from 0.20 to 0.60 cN / dtex at 180° C given a pretensioning force of 0.01 cN / dtex and a duration of action of two minutes.

Description

[0001] 202406190

[0002] 1

[0003] Description

[0004] The invention relates to a vehicle tire and a method for manufacturing a vehicle tire. It also discloses the use of polyester cords as reinforcing materials in the production of coiled bandages during tire manufacturing.

[0005] In the field of modern vehicle tire development, there is a continuous need to further optimize tire properties. Experts are aware that many of the numerous relevant properties are interconnected and that conflicting objectives regularly arise regarding these parameters. Therefore, many developments focus on identifying optimally coordinated systems where selected properties can be optimized without adversely affecting the remaining tire characteristics.

[0006] An important component of modern vehicle tires is the cap ply, also known as the "cap ply." This reinforcing layer, which is typically located beneath the tread of a vehicle tire, gets its name from the fact that it is usually wound onto the underlying tire blank from a strip of spool material. At the time of tire manufacturing, this strip of spool material consists of a vulcanizable rubber compound in which reinforcing elements, usually in the form of cords, are embedded.

[0007] The coiled band, usually positioned above the belt plies, has a significant influence on the mechanical properties of the vehicle tire, particularly its load-bearing capacity. At the same time, the coiled band also regularly increases the overall weight of the tire, which can negatively impact fuel consumption, among other things. Furthermore, the necessity of a coiled band is often perceived as disadvantageous with regard to some relevant rolling characteristics, especially rolling resistance. 202406190

[0008] 2

[0009] In current technology, polyamide PA6.6 is the most commonly used material for reinforcing cords in coiled tires. However, this material has a disadvantage due to its relatively low modulus and comparatively poor hysteresis properties. The former affects circumferential stiffness and thus numerous related properties, such as high-speed performance, contour in relation to centrifugal force growth at high speeds, and handling behavior (C_Alpha). The latter results in lower rolling resistance and, due to increased heat buildup, can lead to further disadvantages in high-speed performance and durability.

[0010] Another disadvantage associated with the use of coiled tire casings is the need for an additional manufacturing step and the requirement for further materials needed for tire production. This disadvantage is particularly significant with the established use of PA6.6, as its availability on the global market has been limited in recent years, resulting in relatively high costs for its use.

[0011] In addition to the disadvantages described above, it has also been found that the use of coiled tire bands can create potential sources of material defects in the tire due to the additional component and the resulting material boundaries. In particular, coiled tire bands can be used in the edge areas, where they extend beyond the widest belt layer (usually the bottom layer) relative to the tire's axial direction. When coiled tire bands are used, these edge areas are comparatively susceptible to material fatigue, cracks in the reinforcing layers, and other defects that can lead to premature tire failure, especially under any type of compression associated with dynamic alternating loads (tension / compression / bending) during tire operation.

[0012] The primary objective of the present invention was to eliminate or at least reduce the disadvantages of the prior art.

[0013] In particular, the object of the present invention was to provide a high-performance vehicle tire, especially a pneumatic vehicle tire, which has excellent performance characteristics and advantageous durability. 202406190

[0014] 3

[0015] It was an object of the present invention to make it possible to manufacture the specified vehicle tire with a reduced weight.

[0016] Furthermore, it was an object of the present invention that the vehicle tire should have an advantageous rolling resistance, in particular resolving the conflict of objectives between favorable rolling resistance and advantageous durability in the most favorable way possible.

[0017] A further object of the present invention was that the vehicle tire in question should enable a reduction in dependence on polyamide-based raw materials in tire manufacturing, in particular PA6.6. A particular object of the present invention was that the vehicle tire in question should enable a reduction in the need for fossil resources for tire production. In this respect, it was desirable that the vehicle tire in question should enable greater reliance on materials from renewable resources and / or materials from the circular economy.

[0018] Another important objective of the present invention was to ensure that the vehicle tire to be specified should have advantageous durability, particularly under dynamic alternating loads during later operation of the vehicle tire, and it was particularly desirable that the susceptibility of the vehicle tire to material defects in the edge area of ​​the coil bandages, especially in the part of the coil bandage extending beyond the belt, should be reduced as much as possible.

[0019] An additional objective of the present invention was that the vehicle tires to be specified should be manufacturable in the most time- and cost-efficient manner possible.

[0020] Against this background, a further objective of the present invention was to provide a method for manufacturing the vehicle tires to be specified.

[0021] A secondary objective of the present invention was also to provide an advantageous use of polyester cords as reinforcing agents in the production of coiled bandages during tire manufacturing. 202406190

[0022] 4

[0023] The inventors of the present invention have now found that the problems described above can be solved if, starting from a conventional vehicle tire construction, specific polyester cords are used as reinforcement carriers, at least in the edge sections of the coil bandage, which consist at least partially of polyester and which have a comparatively low fineness, if they exhibit a particularly high heat shrinkage and a specific shrinkage force, as defined in the claims.

[0024] Advantageously, this method yields a vehicle pneumatic tire which advantageously resolves the conflict of objectives between advantageous rolling characteristics, in particular favorable rolling resistance, on the one hand and good durability on the other.

[0025] The inventors have discovered that by using polyester cords, while maintaining the other properties of the coiled tire, the amount of EPDM can be reduced. This leads to reduced twisting capacity and lower energy consumption, ultimately resulting in lower CO2 emissions during subsequent use. Furthermore, the reduction in EPDM made possible by the invention contributes to improved rolling resistance. In addition, the manufacturing of the coiled tire blank within the vehicle tire blank is simplified in some cases, for example, when using a rubberized single cord.

[0026] It has proven particularly advantageous for the corresponding vehicle tires that they exhibit a particularly favorable durability and that the use of the specific polyester cords can advantageously reduce the occurrence of material defects in the edge area of ​​the coil bandage, especially under dynamic alternating loads.

[0027] The aforementioned problems are thus solved by the subject matter of the invention as defined in the claims. Preferred embodiments of the invention are described in the dependent claims and the following descriptions.

[0028] Such embodiments, which are hereinafter referred to as preferred, are in particularly preferred embodiments with features other than preferred 202406190

[0029] The embodiments described in Section 5 are combined. Combinations of two or more of the embodiments described below as particularly preferred are therefore especially preferred. Also preferred are embodiments in which a feature of one embodiment described as preferred to any extent is combined with one or more further features of other embodiments described as preferred to any extent. Features of preferred methods and uses result from the features of preferred vehicle tires.

[0030] Particularly preferred embodiments of the invention are disclosed in the exemplary embodiments. Particularly preferred embodiments of the invention have two or more, preferably three or more, and most preferably four or more, of the preferred features of the invention disclosed below, which are also implemented in the exemplary embodiments.

[0031] The invention relates in particular to a vehicle tire, manufactured or manufacturable by vulcanizing a vehicle tire blank, wherein the vehicle tire blank comprises: i) a carcass blank comprising one or more first reinforcing elements embedded in a first vulcanizable rubber compound, ii) at least one belt ply blank located further outwards in the radial direction relative to the carcass blank, comprising one or more second reinforcing elements embedded in a second vulcanizable rubber compound, iii) at least one bandage blank located further outwards in the radial direction relative to the belt ply blank, comprising one or more third reinforcing elements embedded in a third vulcanizable rubber compound, wherein the bandage blank has, with respect to the transverse direction, a first edge section with a width of 0.2°BB, a second edge section with a width of 0.2°BB,and includes an intermediate central section with a width of 0.6°BB, where BB is the width of the bandage blank in the transverse direction, 202406190,

[0032] 6 iv) at least one tread blank located further outwards in the radial direction relative to the bandage blank, comprising at least one fourth vulcanizable rubber compound, wherein at least a portion of the third reinforcing elements in the first edge section and in the second edge section are polyester cords, wherein the polyester cord(s) consist at least partially of polyester, wherein the polyester cord(s) are cords with a construction of AxB, wherein A is in the range of 300 to 800 dtex, and B is in the range of 1 to 3, wherein the polyester cord(s) exhibit a heat shrinkage, determined according to ASTM D885 from 2014 at 180 °C, with a preload of 0.01 cN / dtex and an exposure time of two minutes, of 5% or more, and wherein the polyester cord(s) exhibit a shrinkage force, determined according to ASTM D885 from 2014 at 180 °C, with a preload of 0.01 cN / dtex and a duration of action of two minutes, in the range of 0.20 to 0,exhibit 60 cN / dtex.

[0033] The invention relates to a vehicle tire. Vehicle tires in general and methods for their manufacture are well known to those skilled in the art. An exemplary vehicle tire according to the invention is described, wherein the vehicle tire is a passenger car tire or a truck tire, preferably a passenger car tire. An exemplary additional or alternative vehicle tire according to the invention is described, wherein the vehicle tire is a pneumatic tire.

[0034] A key aspect of the present invention is the use of specific reinforcing elements in the coiled tire casing. To achieve the advantageous effects of the present invention, it is necessary that the specific polyester cords used in the manufacture of the vehicle tire exhibit a specific heat shrinkage and a certain shrinkage force. These properties of the polyester cords are properties of the base materials used in the manufacturing process, which must be determined as such in the polyester cords to be incorporated into the vehicle tire, i.e., in particular before their 202406190

[0035] 7

[0036] Embedding in a vulcanizable rubber compound and prior to the vulcanization of the rubber tire.

[0037] During the vulcanization process used in the manufacture of the vehicle tire, the polyester cords are subjected to thermal stress, which alters the shrinkage behavior of the thermally stressed polyester cords compared to the original material, particularly due to the resulting shrinkage. This means that the vehicle tire according to the invention can expediently only be defined by the process used for its manufacture. This is especially true because the complex crosslinking processes of vulcanizable rubber compounds, which occur during vulcanization when the vulcanizable rubber compounds are converted into rubber materials, can hardly be described otherwise. For this reason, the vehicle tire according to the invention is defined by its manufacturability from a specific vehicle tire blank.

[0038] In accordance with expert understanding, a vehicle tire can be obtained from such a vehicle tire blank through vulcanization. The concept of vulcanization, as well as suitable processes and equipment, such as vulcanization molds, are well known to those skilled in the field of rubber processing. During vulcanization, the vulcanizable rubber compounds used in the vehicle tire blank are transformed into the corresponding rubber materials.In other words, it is a vehicle tire according to the invention, wherein the first vulcanizable rubber compound can be converted into a first rubber material by vulcanization, and / or wherein the second vulcanizable rubber compound can be converted into a second rubber material by vulcanization, and / or wherein the third vulcanizable rubber compound can be converted into a third rubber material by vulcanization, and / or wherein the fourth vulcanizable rubber compound can be converted into a fourth rubber material by vulcanization.

[0039] Suitable vulcanizable rubber compounds for the individual blank components, which can be converted into corresponding rubber materials by means of vulcanization, are 202406190

[0040] 8 are already well known to the person skilled in the art and are not the focus of the present invention, so reference can be made here to corresponding vulcanizable rubber compounds from the prior art, which are regularly formulated on the basis of diene rubbers.

[0041] The inventors have succeeded in identifying particularly suitable temperature ranges for the vulcanization of vehicle tires, which, especially in combination with the specific shrinkage behavior of the polyester cords used, allow for excellent results regarding the durability of the vehicle tires, particularly advantageous resistance to material defects in the edge region of the coil bandage. A preferred vehicle tire according to the invention is one that is manufactured or can be manufactured by vulcanizing a vehicle tire blank at a temperature in the range of 130 to 200 °C, based on the operating temperature of the vulcanization device used for vulcanization or of the working fluid used in the vulcanization device for temperature control, in particular steam, or by energy-equivalent electrical temperature control.

[0042] In the foregoing definition, the components of the vehicle tire blank necessary for understanding the invention are defined, whereby it follows from the respective terms used, for example carcass blank and bandage blank, that the corresponding components of the vehicle tire are obtained from the corresponding components of the vehicle tire blank during the vulcanization process in the manufacture of the vehicle tire according to the invention, for example the tire carcass and the spool bandage.

[0043] The respective partial blanks in the vehicle tire blank underlying the invention thus correspond in the vulcanized vehicle tire to the corresponding component, i.e., the carcass blank to the tire carcass, the bandage blank to the coiled bandage, the belt ply blanks to the belt plies, and the tread blank to the tread. Those skilled in the art understand that further partial blanks may also be present in the vehicle tire blank, which serve to realize typical tire components. 202406190

[0044] 9 for example sidewall blanks or tire inner layer blanks, but these are not necessary for the definition and understanding of the invention.

[0045] The carcass blank and tread blank defined above serve, within the scope of the present invention, in particular to clearly define the subject matter of the invention, by means of which the structure can be expediently described. It can be seen as an advantage of the invention that these blanks are not fundamentally limited in any specific way, so that a wide variety of designs known from the prior art for other vehicle tires can be advantageously used for the carcass blank and the tread blank. An exemplary vehicle tire according to the invention is shown, wherein the first reinforcing elements are selected from the group consisting of textile reinforcing elements, preferably polyester-based textile reinforcing elements, and particularly preferably PET-based textile reinforcing elements.An example is also, or alternatively, a vehicle tire according to the invention, wherein the first reinforcing elements enclose a minimum angle of intersection with the circumferential direction in the range of 85° to 90°, preferably in the range of 87° to 90°, particularly preferably in the range of 89° to 90°.

[0046] With regard to the tread, the use of a cap / base construction is particularly preferred, i.e., a vehicle tire according to the invention, wherein the tread blank comprises two or more different vulcanizable rubber compounds, and / or wherein the tread blank has a cap / base construction.

[0047] The inventors of the present invention assume that the advantageous properties achieved with the vehicle tires according to the invention are largely due to the interaction between the coiled bandage equipped with specific polyester cords and the underlying belt layers. Without wishing to be bound by this theory, the inventors assume that this is due to the interaction of the belt layers with the coiled bandage during the manufacturing process. When the tire is lifted into the heating mold, the aim is always to ensure that at least a positive bulge is maintained at the belt edge, i.e., that there is no reduction in diameter. The coiled bandage, wound to the edge of the belt or even beyond it, which, for example, is shown in 202406190

[0048] The cord, which is 10 mm wider than the belt is wound, can be compressed after being lifted into the heating mold, causing the reinforcing elements to become compressed or wavy. According to the inventors, this negatively affects dynamic alternating loads and can promote material fatigue or cracking of the reinforcing elements. This is counteracted by using specific polyester cords that exhibit high thermal shrinkage, thus eliminating or at least significantly reducing these compressions.

[0049] Against this background, the inventors have succeeded in identifying particularly advantageous configurations for the design of the belt ply blanks, with which particularly advantageous vehicle tires according to the invention can be obtained. A preferred vehicle tire according to the invention comprises two or more, preferably exactly two for passenger cars, belt ply blanks arranged one above the other with respect to the radial direction, wherein the belt ply blank located radially inside is preferably the widest belt ply blank. A preferred additional or alternative vehicle tire according to the invention also includes a second reinforcing element selected from the group consisting of metallic reinforcing elements, preferably steel-based reinforcing elements, and particularly preferably reinforcing elements made of recycled steel.A vehicle tire according to the invention is preferred, either additionally or alternatively, wherein the second reinforcing elements enclose a minimum angle of intersection with the circumferential direction in the range of 10° to 60°, preferably in the range of 15° to 50°, and particularly preferably in the range of 20° to 45°. A vehicle tire according to the invention is particularly preferred in this respect, wherein the second reinforcing elements in different belt ply blanks have different slope directions, so that a crossed pattern is obtained in the top view.

[0050] With regard to the design and arrangement of the second reinforcing elements, a vehicle tire according to the invention is preferred, wherein the second reinforcing elements have a mean diameter of 0.85 mm or less, preferably 0.7 mm or less, and particularly preferably 0.65 mm or less. A vehicle tire according to the invention is also preferred, or alternatively, wherein the second reinforcing elements have a mean diameter of 0.85 mm or less, preferably 0.7 mm or less, and particularly preferably 0.65 mm or less.

[0051] 11

[0052] The reinforcing elements in the belt layer blank have a mean distance to adjacent second reinforcing elements in the range of 0.4 to 1 mm, preferably in the range of 0.42 to 0.96 mm, particularly preferably in the range of 0.44 to 0.86 mm, and most preferably in the range of 0.44 to 0.75 mm.

[0053] A key aspect of the present invention lies in the specific design of the tire blank. In some aspects, however, the tire blank resembles those known to those skilled in the art, namely, in particular, that the tire blank is typically obtained by winding a strip-shaped spool material comprising the third reinforcing elements embedded in a vulcanizable rubber compound. This also results in the third reinforcing elements typically running largely parallel to the circumferential direction. A vehicle tire according to the invention is therefore particularly relevant, wherein the tire blank is manufactured or manufacturable by winding a strip-shaped spool material comprising the third vulcanizable rubber compound and the third reinforcing elements.Particularly relevant, additionally or alternatively, is a vehicle tire according to the invention, wherein the third reinforcing element(s) enclose a smallest angle of intersection with the circumferential direction in the range of 0° to 10°, preferably in the range of 0° to 5°, particularly preferably in the range of 0° to 2°.

[0054] With regard to the basic dimensions, a vehicle tire according to the invention is preferred, wherein the bandage blank has a radial average thickness in the range of 0.45 to 0.75 mm, preferably in the range of 0.7 to 0.7 mm. Additionally or alternatively, a vehicle tire according to the invention is preferred, wherein the third reinforcing element(s) are embedded in the third vulcanizable rubber compound such that the distance to at least one of the surfaces of the bandage blank, preferably to both surfaces, is in the range of 0.1 to 0.2 mm, preferably in the range of 0.1 to 0.15 mm.

[0055] According to the inventors, the interplay between the specific bandage blanks and the belt ply blanks during vulcanization is of crucial importance. 202406190

[0056] 12

[0057] It is preferred that the coil bandage and the wider belt have a similar width with respect to the transverse direction perpendicular to the circumferential direction. For this reason, it is preferred that the bandage blank, with respect to the transverse direction perpendicular to the circumferential direction, terminates just before the edge of the widest belt layer blank or even extends beyond it. This means that, viewed from the radial direction, the bandage blank is positioned transversely such that it lies somewhere between 10 mm in front of the edge of the widest belt layer blank and 15 mm behind the edge of the widest belt layer blank. According to the inventors, it is preferred that the bandage blank be designed in this way on both sides, and for some embodiments, it is also particularly preferred to provide a certain overhang of the coil bandage.

[0058] A vehicle tire according to the invention is therefore generally preferred, wherein the edge of the bandage blank, with respect to the transverse direction orthogonal to the circumferential direction, has a projection of 0 to 15 mm, preferably 0 to 10 mm, and particularly preferably 0 to 5 mm, from the edge of the widest belt layer blank on at least one side, preferably both sides, and / or wherein the edge of the bandage blank, with respect to the transverse direction orthogonal to the circumferential direction, has a projection of -10 to 10 mm, preferably -5 to 5 mm, from the edge of the widest belt layer blank on at least one side, preferably both sides. Negative numbers here indicate that the belt layer blank is wider than the coil bandage blank.

[0059] In order to meaningfully define the vehicle tires according to the invention, the tire blank is divided in the transverse direction orthogonal to the circumferential direction into three virtual sections within the scope of the present invention, namely a central section which extends over 60% of the width and is bordered on both sides by an edge section which occupies 20% of the total width.

[0060] As defined above, the third strength carriers, i.e., the strength carriers of the bandage blank, are located in the two edge sections, i.e., the sections which extend at least to the edge of the belt layer blank and preferably over 202406190

[0061] 13. These extend beyond the present invention to specific cords, which are referred to as "polyester cords". A corresponding procedure for defining the reinforcing elements is generally known from the prior art, for example from DE 102020206314 A1, which, however, teaches a fundamentally opposite construction in which the polyester PET is only used in the cords in the central section.

[0062] Within the scope of the present invention, the term “polyester cords” serves as a term to distinguish the specific strength carriers from other strength carriers that may be present, wherein the polyester cords are characterized not only by the specific material selection but also by the cord construction and shrinkage behavior, as defined above.

[0063] According to the inventors, achieving the advantageous effects requires that the third reinforcing elements, at least in the first and second edge sections, be formed at least partially by corresponding polyester cords. However, the inventors also consider it advantageous to implement the third reinforcing elements in the intermediate central section as such polyester cords. In particular, in contrast to DE 102020206314 A1, this significantly simplifies the production of corresponding bandage blanks, since, for example, the same strip-shaped spool material can be used for the entire bandage blank.In an advantageous further development of this idea, it is particularly preferred to use the same strip-shaped spool material for the edge sections and, more preferably, for the edge sections and the central section, and thus ultimately to use identical reinforcing elements, wherein, in a preferred embodiment, the corresponding cords can also extend completely through all sections. A preferred vehicle tire according to the invention is therefore one in which the third reinforcing element(s) in the central section are polyester cords. A preferred additional or alternative vehicle tire according to the invention is one in which the third reinforcing element(s) in the first edge section and in the second edge section are identical. A particularly preferred vehicle tire according to the invention is 202406190.

[0064] 14 wherein the third reinforcement carrier(s) in the first edge section and in the second edge section, and in the central section are of the same design.

[0065] According to the inventors, the advantages of the vehicle tires according to the invention are already realized if at least a portion of the third reinforcing elements used in the tire blank are made in the form of the specific polyester cords. At the same time, it is preferred for essentially all embodiments to make the reinforcing elements in the corresponding sections as far as possible from the respective polyester cords, and it is particularly preferred to make essentially all of the third reinforcing elements in the form of the specific polyester cords of the present invention.A preferred vehicle tire according to the invention is therefore one in which 50% or more, preferably 70% or more, particularly preferably 90% or more, very preferably 95% or more, and particularly preferably substantially 100% of the third reinforcing elements in the first edge section and in the second edge section, preferably in the first edge section, in the second edge section, and in the central section, are polyester cords.

[0066] As explained above, the specific “polyester cords” have special features compared to the state of the art, both in terms of the chemical nature of the materials used and the cord construction and shrinkage behavior.

[0067] A first important aspect, which in particular makes it possible to implement the cord construction according to the above definition and to achieve the desired heat shrinkage and shrinkage strength, is that the "polyester cords," in accordance with their designation, are at least partially made of a polyester. Even if it would theoretically be possible to combine the polyester in the polyester cords with other polymers, it is preferred for most embodiments to make the polyester cords as largely as possible from a corresponding polyester. A preferred vehicle tire according to the invention is therefore one in which the polyester cord(s) comprise a mass fraction of 50% or more, preferably 70% or more, and particularly preferably 90% or more.

[0068] 15 particularly preferably 95% or more, particularly preferably consisting of substantially 100% polyester.

[0069] In the inventors' experiments, particularly suitable polyester materials were identified with which especially high-performance vehicle tires according to the invention can be obtained, with the use of PET being identified as particularly advantageous. A preferred vehicle tire according to the invention is one in which the polyester is selected from the group consisting of polyethylene terephthalates, polybutylene terephthalates, and polyethylene naphthalates, preferably polyethylene terephthalates.

[0070] A major advantage of the present invention is that the polyesters used do not need to be produced, or at least not entirely, from fossil resources. Rather, it is advantageously possible to use both recycled polyesters, i.e., polyester recovered from previously used polyester products within the framework of a circular economy, and bio-based polyesters. In particular, the use of recycled, bio-based polyesters is conceivable and advantageous. The term "bio-based" is clear to those skilled in the art and means that the polyester in question is produced at least partially, preferably predominantly, and most preferably essentially entirely, by polymerizing starting materials derived from plant or animal raw materials, preferably plant-based raw materials.Particularly preferred are bio-based polyesters which are produced at least partially, preferably predominantly, and especially preferably substantially entirely from renewable plant-based raw materials. Such bio-based polyesters, which are produced at least partially from renewable raw materials, can be identified by their 14C isotope content and reliably identified according to ASTM D 6866. In this context, a vehicle tire according to the invention is preferred, wherein the polyester is a recycled polyester. Additionally or alternatively, a vehicle tire according to the invention is preferred, wherein the polyester is at least partially, preferably predominantly by mass, and especially preferably entirely a bio-based polyester. 202406190.

[0071] 16

[0072] Regarding the construction of the polyester cords, the inventors have succeeded in identifying particularly preferred embodiments. It has been shown that the aforementioned conflicting objectives, and in particular an advantageous rolling resistance, can be achieved with relatively minor refinements. A preferred embodiment is a vehicle tire according to the invention, wherein A is in the range of 350 to 780 dtex, preferably in the range of 400 to 760 dtex, particularly preferably in the range of 450 to 740 dtex, and most preferably in the range of 500 to 720 dtex. A preferred embodiment is additionally or alternatively a vehicle tire according to the invention, wherein B is 2 or 3, preferably 2.

[0073] A preferred embodiment of the polyester cords is a vehicle tire according to the invention, wherein the polyester cord(s) each comprise one or more multifilament yarns, the number of filaments in the yarn preferably being in the range of 100 to 300, particularly preferably in the range of 100 to 250, and most preferably in the range of 100 to 200. A preferred or alternative embodiment is a corresponding vehicle tire according to the invention, wherein the polyester cord(s) have a mean diameter of 0.5 mm or less, preferably 0.45 mm or less, and particularly preferably 0.4 mm or less.

[0074] With regard to the design of the entire bandage blank, a vehicle tire according to the invention is preferred, wherein the polyester cords in a 10 mm wide strip of the bandage blank have a strip strength in the range of 550 to 1100 N / 10mm, preferably in the range of 550 to 1000 N / 10 mm, particularly preferably 550 to 900 N / 10mm.

[0075] The inventors of the present invention have found that the use of the specific polyester cords of the present invention makes it possible, in principle, to provide a larger distance between the reinforcing elements in the bandage blanks, which is evaluated along the transverse direction perpendicular to the circumferential direction. This advantageously makes it possible to work with relatively low EPDM values. EPDM is a quantity well known to those skilled in the art, which defines the number of reinforcing elements per decimeter in the transverse direction. A vehicle tire according to the invention is preferred, wherein the third reinforcing elements 202406190

[0076] 17 in the bandage blank have an average distance of 0.5 mm or more, preferably 0.6 mm or more, and particularly preferably in the range of 0.5 to 0.8 mm, to adjacent third reinforcing elements. A vehicle tire according to the invention is preferred, or alternatively, wherein the number of third reinforcing elements in the bandage blank per decimeter in the transverse direction is in the range of 60 to 130 epdm, preferably in the range of 60 to 110 epdm, and particularly preferably in the range of 70 to 110 epdm.

[0077] In addition to the specific material selection and the construction defined above, the polyester cords also exhibit specific heat shrinkage and a predetermined shrinkage force. Both heat shrinkage and shrinkage force are well-known quantities for those skilled in the art in the field of textile cords, which can be determined using the established ASTM D 885 standard. Particularly with regard to their very high heat shrinkage, the polyester cords to be used according to the invention differ significantly from those polyester cords, especially PET cords, which have already been proposed in other areas of vehicle tire manufacturing, for example, for use in the carcass.The PET cords known for use in vehicle tires are mostly deliberately so-called HMLS ("High Modulus Low Shrinkage") cords, whose heat shrinkage is less than 2.5% (determined according to ASTM D885 from 2014 at 180 °C, with a preload of 0.01 cN / dtex and a duration of two minutes).

[0078] A preferred vehicle tire according to the invention is one in which the polyester cord(s) exhibit a heat shrinkage, determined at 180 °C, with a pretension force of 0.01 cN / dtex and an effective duration of two minutes, of 5.5% or more, preferably 6.0% or more, particularly preferably 6.5% or more.

[0079] Preferably, or alternatively, a vehicle tire according to the invention is used, wherein the polyester cord(s) have a shrinkage force, determined at 180 °C, with a pretension of 0.01 cN / dtex and an effective duration of two minutes, in the range of 0.22 to 0.55 cN / dtex, preferably in the range of 0.24 to 0.50 cN / dtex. 202406190

[0080] 18

[0081] The invention also relates to a method for manufacturing a vehicle tire according to the invention, comprising the process steps: a) manufacturing or providing a vehicle tire blank, comprising: ai) a carcass blank, comprising one or more first reinforcing elements embedded in a first vulcanizable rubber compound, a.ii) at least one belt ply blank located further outwards in the radial direction relative to the carcass blank, comprising one or more second reinforcing elements embedded in a second vulcanizable rubber compound, a.iii) at least one bandage blank located further outwards in the radial direction relative to the belt layer blank, comprising one or more third reinforcing elements embedded in a third vulcanizable rubber compound, wherein the bandage blank comprises, in the transverse direction, a first edge section with a width of 0.2°BB, a second edge section with a width of 0.2°BB, and a central section arranged between them with a width of 0.6°BB, where BB is the width of the bandage blank in the transverse direction, a.iv) at least one tread blank located further outwards in the radial direction relative to the tire blank, comprising at least one fourth vulcanizable rubber compound, and b) vulcanizing the vehicle tire blank to obtain the vehicle tire, wherein at least part of the third reinforcing elements in the first edge section and in the second edge section are polyester cords, wherein the polyester cord(s) consist at least partially of polyester, wherein the polyester cord(s) are cords having a construction of AxB, wherein A is in the range of 300 to 800 dtex, and B is in the range of 1 to 3, 202406190.

[0082] 19 wherein the polyester cord(s) exhibit a heat shrinkage, determined according to ASTM D885 from 2014 at 180 °C, with a prestress of 0.01 cN / dtex and an exposure time of two minutes, of 5% or more, wherein the polyester cord(s) exhibit a shrinkage force, determined according to ASTM D885 from 2014 at 180 °C, with a prestress of 0.01 cN / dtex and an exposure time of two minutes, in the range of 0.20 to 0.60 cN / dtex.

[0083] Of particular relevance is a method according to the invention, wherein method step a) comprises the following sub-steps: aa) manufacturing or providing the carcass blank, ab) arranging the belt ply blank radially outside the tire carcass blank, ac) applying the bandage blank radially outside the belt ply blank, ad) applying a tread blank radially outside the bandage blank.

[0084] A preferred method according to the invention is wherein the application of the bandage blank is carried out by winding on a web-shaped spool material comprising the third vulcanizable rubber compound and the third reinforcing agents.

[0085] A preferred method, either additionally or alternatively, is one in which vulcanization takes place at a temperature in the range of 130 to 200 °C, preferably in the range of 130 to 180 °C, relative to the operating temperature of the vulcanization device used for vulcanization or of the working fluid used in the vulcanization device for temperature control, in particular steam, or an energy-equivalent electrical temperature control. A preferred method, either additionally or alternatively, is one in which vulcanization takes place in a vulcanization mold.

[0086] Preferably, or alternatively, a method according to the invention is used, wherein method step a) is carried out on a rotatable tire assembly drum. 202406190

[0087] 20

[0088] The use of polyester cords as reinforcing elements in the manufacture of coiled bandages during tire production to improve rolling resistance and durability is also disclosed, wherein the polyester cords are used at least in the edge regions of the coiled bandage, wherein the polyester cords consist at least partially of polyester, wherein the polyester cords are cords with a construction of AxB, where A is in the range of 300 to 800 dtex, where B is in the range of 1 to 3, wherein the polyester cords exhibit a heat shrinkage, determined according to ASTM D885 from 2014 at 180 °C, with a pretension of 0.01 cN / dtex and an operating time of two minutes, of 5% or more, wherein the polyester cords exhibit a shrinkage force, determined according to ASTM D885 from 2014 at 180 °C, with a pretension of 0.01 cN / dtex and an operating time of two minutes, exhibit values ​​in the range of 0.20 to 0.60 cN / dtex.

[0089] The invention and preferred embodiments of the invention are explained and described in more detail below with reference to the accompanying figure. The figure shows:

[0090] Fig. 1 shows a schematic cross-sectional view through the tire crown of a vehicle tire blank for use in the manufacture of vehicle tires according to the invention in a preferred embodiment.

[0091] Fig. 1 shows a schematic cross-sectional view through the tire crown of a vehicle tire blank 10, from which a vehicle tire according to the invention can be produced by vulcanization.

[0092] The depicted vehicle tire blank 10 is a vehicle tire blank 10 for a passenger car tire, designed as a pneumatic tire. In the example shown, the outermost layer of the vehicle tire blank 10 is formed by a tread blank 24, which is fitted with a cap / base. 202406190

[0093] 21

[0094] The construction is designed and accordingly comprises two different vulcanizable rubber compounds.

[0095] The vehicle tire blank 10 comprises a carcass blank 12, which in the example shown includes a large number of PET reinforcement carriers embedded in a first vulcanization of a rubber compound.

[0096] Further outwards in the radial direction, the vehicle tire blank 10 comprises two belt ply blanks 14a, 14b, which are arranged one above the other in the radial direction and comprise a plurality of steel cords as second reinforcing elements, which, unlike the essentially radially extending reinforcing elements of the carcass blank 12 in the example shown, run with a cord angle of about 30° relative to the circumferential direction, wherein the second reinforcing elements in the different belt ply blanks 14a, 14b are designed with opposing slopes, so that the second reinforcing elements in the belt ply blanks 14a, 14b run crossed.

[0097] In the example shown in Fig. 1, the second reinforcing elements have a mean diameter of approximately 0.5 mm and are arranged in the respective belt layer blanks 14a, 14b at a distance of approximately 0.6 mm. Further outwards in the radial direction from the belt layer blanks 14a, 14b is the bandage blank 16, which was produced by winding a strip-shaped coil material onto it and extends approximately 12 mm beyond the widest belt layer blank 14a on both sides in the transverse direction.

[0098] The bandage blank 16 can be divided into a first edge section 18, a second edge section 20, and an intermediate central section 22 to describe its structure, as indicated by the dashed brackets.

[0099] In the example shown in Fig. 1, the bandage blank 16 is designed such that the strip-shaped coil material comprises several third reinforcing elements, which are arranged in a third vulcanizable rubber compound and which, as a result of the coiling process, wind through the first edge section 18, the second edge section 20, and the central section 22. 202406190

[0100] 22

[0101] In the preferred vehicle tire blank 10 of Fig. 1, all of the third reinforcing elements are designed as polyester cords, which consist essentially entirely of polyethylene terephthalate (PET). In the preferred example of Fig. 1, the polyester cords have a cord construction of 360x2, 550x2 or 720x2, with the configuration with 550x2 being particularly preferred.

[0102] The heat shrinkage of the polyester cords in the vehicle tire blank 10 is more than 6.5% in the example shown, whereas the shrinkage force, which, like the heat shrinkage, is determined according to ASTM D 885 from 2014 at 180 °C and a prestress force of 0.01 cN / dtex and a duration of two minutes, is approximately 0.35 cN / dtex.

[0103] In the example of Fig. 1, the polyester cords each have about 150 filaments and are so completely embedded in the third vulcanizable rubber compound that about 0.12 mm of vulcanizable herbaceous compound lies between the polyester cords and the surface of the bandage blank 16.

[0104] The polyester used for the production of the polyester cords was obtained from mechanically recycled PET for the embodiment of the vehicle tire blank 10 shown in Fig. 1.

[0105] Advantageous vehicle tires according to the invention can be obtained from the vehicle tire blank 10 shown in Fig. 1 by vulcanization, preferably at a temperature in the range of 130 to 180 °C.

[0106] 202406190

[0107] 23

[0108] Reference symbol list

[0109] 10 vehicle tire blanks

[0110] 12 Carcass blanks

[0111] 14a, b belt layer blank 16 bandage blank

[0112] 18 first marginal section

[0113] 20 second marginal note

[0114] 22 Central section

[0115] 24 tread strip blanks

Claims

202406190 24 Claims 1. A vehicle tire, manufactured or manufactureable by vulcanizing a vehicle tire blank (10), wherein the vehicle tire blank (10) comprises: i) a carcass blank (12) comprising one or more first reinforcing elements embedded in a first vulcanizable rubber compound, ii) at least one belt ply blank (14a, 14b) located further outwards in the radial direction relative to the carcass blank (12), comprising one or more second reinforcing elements embedded in a second vulcanizable rubber compound, iii) at least one bandage blank (16) located further outwards in the radial direction relative to the belt ply blank (14a, 14b), comprising one or more third reinforcing elements embedded in a third vulcanizable rubber compound, wherein the bandage blank (16) has, with respect to the transverse direction, a first edge section (18) with a width of 0.2°BB, a second edge section (20) with a width of 0.2°BB,and an intermediate central section (22) with a width of 0.6°BB, where BB is the width of the bandage blank (16) in the transverse direction, iv) at least one tread blank (24) located further outwards in the radial direction relative to the bandage blank (16), comprising at least a fourth vulcanizable rubber compound, wherein at least a portion of the third reinforcing elements in the first edge section (18) and in the second edge section (20) are polyester cords, wherein the polyester cord(s) consist at least partially of polyester, wherein the polyester cord(s) are cords with a construction of AxB, where A is in the range of 300 to 800 dtex, where B is in the range of 1 to 3, wherein the polyester cord(s) exhibit a heat shrinkage, determined according to ASTM D885 from 2014 at 180 °C, with a preload of 0.01 cN / dtex and an action duration of two minutes, of 5% or more, and, 202406190 25 wherein the polyester cord(s) exhibit a shrinkage force, determined according to ASTM D885 from 2014 at 180 °C, with a prestress of 0.01 cN / dtex and an action time of two minutes, in the range of 0.20 to 0.60 cN / dtex.

2. Vehicle tire according to claim 1, wherein the vehicle tire is manufactured or can be manufactured by vulcanizing the vehicle tire blank (10) at a temperature in the range of 130 to 200 °C relative to the working temperature of the vulcanizing device used for vulcanization or of the working fluid used in the vulcanizing device for temperature control or an energy-equivalent electrical temperature control.

3. Vehicle tire according to one of claims 1 or 2, wherein the vehicle tire blank (10) comprises two or more belt ply blanks (14a, 14b) which are arranged one above the other with respect to the radial direction.

4. Vehicle tire according to one of claims 1 to 3, wherein the second reinforcing elements are selected from the group consisting of metallic reinforcing elements.

5. Vehicle tire according to one of claims 1 to 4, wherein the tire blank (16) has a mean thickness in the radial direction in the range of 0.45 to 0.75 mm.

6. Vehicle tire according to one of claims 1 to 5, wherein the third reinforcing element(s) are embedded in the third vulcanizable rubber compound such that the distance to at least one of the surfaces of the tire blank (16) is in the range of 0.1 to 0.2 mm. 202406190 26 7. Vehicle tire according to one of claims 1 to 6, wherein the edge of the tire blank (16) has, with respect to the transverse direction orthogonal to the circumferential direction, a projection of 0 to 15 mm, preferably in the range of 0 to 10 mm, particularly preferably 0 to 5 mm, from the edge of the widest belt ply blank (14a, 14b) on at least one side, preferably on both sides, and / or wherein the edge of the tire blank (16) has, with respect to the transverse direction orthogonal to the circumferential direction, a projection of -10 to 10 mm, preferably in the range of -5 to 5 mm, from the edge of the widest belt ply blank (14a, 14b) on at least one side, preferably on both sides.

8. Vehicle tire according to one of claims 1 to 7, wherein the polyester cord(s) consist of polyester to a mass fraction of 50% or more.

9. Vehicle tire according to any one of claims 1 to 8, wherein the polyester is selected from the group consisting of polyethylene terephthalates, polybutylene terephthalates and polyethylene naphthalates.

10. Vehicle tire according to any one of claims 1 to 9, wherein the polyester is a recycled polyester, and / or wherein the polyester is at least partially a bio-based polyester.

11. Vehicle tire according to any one of claims 1 to 10, wherein A is in the range of 350 to 780 dtex, and / or wherein B is 2 or 3. 202406190 27 12. Vehicle tire according to one of claims 1 to 11, wherein the number of third reinforcing elements in the tire blank (16) per decimeter in the transverse direction is in the range of 60 to 130 epdm.

13. Vehicle tire according to any one of claims 1 to 12, wherein the polyester cord(s) exhibit a heat shrinkage, determined at 180 °C, with a pretension force of 0.01 cN / dtex and an effective duration of two minutes, of 5.5% or more.

14. Vehicle tire according to one of claims 1 to 13, wherein the polyester cord(s) have a shrinkage force, determined at 180 °C, with a pretension force of 0.01 cN / dtex and an effective duration of two minutes, in the range of 0.22 to 0.55 cN / dtex.

15. Method for manufacturing a vehicle tire according to any one of claims 1 to 14, comprising the process steps: a) manufacturing or providing a vehicle tire blank (10), comprising: ai) a carcass blank (12), comprising one or more first reinforcing elements embedded in a first vulcanizable rubber compound, a.ii) at least one belt ply blank (14a, 14b) located further outwards in the radial direction relative to the carcass blank (12), comprising one or more second reinforcing elements embedded in a second vulcanizable rubber compound, a.iii) at least one bandage blank (16) located further outwards in the radial direction relative to the belt ply blank (14a, 14b), comprising one or more in 202406190 28 third reinforcing elements embedded in a third vulcanizable rubber compound, wherein the tire blank (16) comprises, in the transverse direction, a first edge section (18) with a width of 0.2°BB, a second edge section (20) with a width of 0.2°BB, and an intermediate central section (22) with a width of 0.6°BB, where BB is the width of the tire blank (16) in the transverse direction, a.iv) at least one tread blank (24) located further outwards in the radial direction relative to the tire blank (16), comprising at least a fourth vulcanizable rubber compound, and b) vulcanizing the vehicle tire blank (10) to obtain the vehicle tire, wherein at least a part of the third reinforcing elements in the first edge section (18) and in the second edge section (20) are polyester cords, wherein the polyester cord(s) consist at least partially of polyester,wherein the polyester cord(s) are cords with a construction of AxB, wherein A is in the range of 300 to 800 dtex, wherein B is in the range of 1 to 3, wherein the polyester cord(s) exhibit a heat shrinkage, determined according to ASTM D885 from 2014 at 180 °C, with a prestress of 0.01 cN / dtex and an exposure time of two minutes, of 5% or more, and wherein the polyester cord(s) exhibit a shrinkage force, determined according to ASTM D885 from 2014 at 180 °C, with a prestress of 0.01 cN / dtex and an exposure time of two minutes, in the range of 0.20 to 0.60 cN / dtex.

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