Pneumatic vehicle tyres with reinforcing layers

Abstract

The invention relates to pneumatic vehicle tyres, wherein the reinforcements of the bandage ply have a multifilament yarn made of PA 6.6 with a fineness of 100 dtex to 1500 dtex, the raw yarn of which has a fineness-related maximum tensile strength of greater than 87 cN / tex, and a thermal shrinkage greater than 6%, wherein the reinforcements of the carcass ply comprise a multifilament yarn made of PET with a fineness of 50 dtex to 2500 dtex, the raw yarn of which has a fineness-related maximum tensile strength of ≥ 70 cN / tex and a thermal shrinkage of less than 8%, and wherein the reinforcements of the belt ply comprise a steel filament with a tensile strength of 3000 N / mm^2 to 4100 N / mm^2 and a carbon content of 0.79 wt.% to 1.10 wt.%. Such a pneumatic vehicle tyre with further improved rolling resistance is still sufficiently robust to withstand particular stresses, such as improper use.

Description

[0001] Description

[0002] Pneumatic vehicle tires having reinforcement layers

[0003] The invention relates to a pneumatic vehicle tire, comprising a carcass having a carcass ply, a belt arranged radially outside the carcass and having a belt ply, and a belt bandage having a bandage layer resting radially outside on the belt, wherein the carcass ply, the belt ply and the bandage layer each have strength members which are embedded in rubber material within the respective layer, arranged parallel and spaced from one another, wherein the strength members of the bandage layer are textile strength members, each formed from at least one multifilament yarn made of polyamide 6.6 (PA 6.6), wherein the strength members of the carcass ply are textile strength members, each formed from at least one multifilament yarn made of polyethylene terephthalate (PET), and wherein the strength members of the belt layer are each formed from at least one steel filament.

[0004] Reinforcement layers for pneumatic vehicle tires, such as the carcass ply, the belt ply, and / or the bandage ply, are of utmost importance and are generally known to those skilled in the art. The reinforcement layers comprise a multitude of reinforcing, thread-like elements, the so-called reinforcement members. The reinforcement members are completely embedded in elastomeric material, for example, by calendering. The reinforcement members of these reinforcement layers take the form of woven fabrics or calendered, continuously wound reinforcement members, for example.

[0005] The rubberized reinforcement layers of appropriate size and design are combined with other components to form a pneumatic vehicle tire. In a pneumatic vehicle tire, the reinforcement layers reinforce the respective components of the tire. At the same time, the pneumatic vehicle tire must be improved with regard to other boundary conditions, such as low rolling resistance. This can be achieved by using comparatively thin and high-strength reinforcement layers. However, the reinforcement layers must still meet the demanding requirements of the respective component of the pneumatic vehicle tire. Especially in highly stressed areas, the interaction of the reinforcement layers of various tire components must be considered to ensure adequate technical properties of the entire tire.For example, in the head area of ​​the pneumatic vehicle tire, in which the reinforcement layers of the carcass, the belt and the belt bandage are arranged to overlap each other at least in sections, not only the required technical properties of the individual components must be taken into account, but the strength and robustness of the entire head area must be ensured.

[0006] To ensure the strength and robustness of a pneumatic vehicle tire, it is common practice to equip the tire's head area with sufficient thickness to ensure strength and robustness against exceptional loads, such as driving over obstacles. However, this, in turn, has a negative impact on other properties, such as low rolling resistance.

[0007] A pneumatic vehicle tire, in particular of a radial design, generally comprises a carcass containing at least one carcass ply, the carcass extending from a crown region of the tire over sidewalls to bead regions and usually anchored there by wrapping tensile bead cores, a profiled tread located radially outside the carcass, and a belt arranged between the tread and the carcass, usually having at least two belt plies, as well as a belt bandage with at least one bandage ply, lying radially outside on the belt and covering at least the belt edges. In a radial design tire, the carcass is designed as a radial carcass, with all or some of the reinforcement members of the radial carcass running approximately in the radial direction in an area of ​​the sidewalls. In this application, "approximately in" a direction means at an angle of 0 to 8° with respect to the respective direction.

[0008] The reinforcements of the carcass, especially the radial carcass, must be sufficiently strong to adequately absorb the forces occurring during tire operation and to ensure long-term durability. In particular, the carcass resists the tire's internal pressure. Driving behavior, especially during high-speed use, is further positively influenced by a high modulus of elasticity at strains of up to approximately 2% to 4% of the carcass' reinforcements. In addition, a reinforcing layer of the carcass during tire production should allow for sufficient elevation during tire construction and in the vulcanization mold to ensure precise tire shaping.In addition, the reinforcements of the carcass should have a high maximum tensile strength and a high elongation at break in order to increase the durability of the tire and to have improved durability with regard to forced elongation, which can occur, for example, when driving through a pothole.

[0009] The belt bandage serves to prevent the tire from buckling due to the centrifugal forces that occur during ferry operation, particularly during high-speed operation. The strength members of the at least one bandage layer of the belt bandage run approximately in the circumferential direction. The at least one bandage layer of the belt bandage is applied during tire production in the form of layers, strips, or individual strength members with strength members embedded in an unvulcanized rubber compound, which are wound or spooled onto the belt. The strength members of the belt bandage are intended to allow sufficient buckling during crowning and in the vulcanization mold during tire production so that the tire can be precisely shaped, and they are intended to ensure good high-speed suitability for ferry operation after the tire has been finished.To meet these requirements, the reinforcements should have a breaking elongation sufficient for tire production. They should be able to be stretched up to an elongation of approximately 3% to 4% with moderate force, and at higher elongations only with very great force. The belt typically has at least two belt layers arranged at an angle to each other. The belt improves the rigidity of the tread in the longitudinal and transverse directions. This serves to transfer power while driving, improves lateral grip, and reduces tire wear.

[0010] Efforts are also being made to further improve the properties of the belt bandage component. EP3254870 A1 and EP3254871 A1 each disclose a reinforcement layer of the belt bandage whose strength member comprises at least one multifilament yarn made of polyamide 6.6. The raw yarn made of polyamide 6.6 has a tenacity-related strength that, at an elongation of 4%, lies in a range of 1.35 cN / dtex to 1.60 cN / dtex, and the strength member has a tenacity-related strength that, at an elongation of 4%, lies in an advantageous range. The comparatively thin reinforcement layers have an advantageous modulus of elasticity for use in the belt bandage and are more fatigue-resistant with regard to alternating compressive and bending stresses.

[0011] Efforts to make the carcass ply(s) as thin as possible by using reinforcements made of high-strength PET are known from EP 3493999 A1. This document discloses a carcass ply comprising cords made of two twisted multifilament PET yarns as reinforcements, wherein the raw PET yarns have a tensile strength of greater than 70 cN / tex, sufficient for the carcass, and a heat shrinkage of less than 4%.

[0012] EP 3544826 A1 discloses belt layers comprising steel filaments with a tensile strength of 3080 N / mm 2 up to 4190 N / mm 2 as a reinforcement. DE10 2019 218 723 A1 discloses a belt layer comprising steel cords of construction 1 + 2 made of three steel filaments with a tensile strength of 3000 N / mm 2 up to 4000 N / mm 2of the same diameter. The development is moving towards further improving the environmental friendliness, in particular the rolling resistance, of rubber products by optimizing the reinforcement layer(s) of a component of the rubber product. By specifically reducing the fineness or diameter of the strength members of a reinforcement layer, and the associated reduction in the thickness of the reinforcement layer, it is possible to reduce energy consumption when the tire component deforms during operation. However, such an optimization of the reinforcement layer comes at the expense of other properties, such as the robustness of the component. If several components of the tire are to contribute to the optimization, the interaction of the individual optimized components in particularly stressed areas of the tire must also be taken into account.This applies, for example, to the head area, where the reinforcement layers of various components, especially the carcass, the belt, and the belt bandage, interact. The robustness of the entire tire must also be ensured even under extreme conditions, such as those that can arise from improper use, such as driving with under-inflation or overloading.

[0013] It was therefore the primary object of the present invention to provide a pneumatic vehicle tire which, while still having a further improved rolling resistance, still has sufficient robustness against particular stresses, such as improper use.

[0014] The object is achieved by a pneumatic vehicle tire according to the features of claim 1.

[0015] The pneumatic vehicle tire according to the invention is characterized in that the multifilament yarn made of PA 6.6 has a fineness of 100 dtex to 1500 dtex, that the raw yarn made of PA 6.6 of the multifilament yarn made of PA 6.6 has a fineness-related maximum tensile strength of greater than 87 cN / tex, determined according to ASTM D885, and a hot shrinkage of greater than 6%, determined at 180°C under a pretension of 0.05 cN / dtex with an exposure time of two minutes. The pneumatic vehicle tire according to the invention is further characterized in that the multifilament yarn made of PET has a fineness of 50 dtex to 2500 dtex and that the raw yarn made of PET of the multifilament yarn made of PET has a fineness-related maximum tensile strength of > 70 cN / tex, determined according to ASTM D885, and a heat shrinkage of less than 8%, determined at 180 °C under a pretension of 0.01 cN / dtex with an exposure time of two minutes.

[0016] The pneumatic vehicle tire according to the invention is further characterized in that the steel filament has a tensile strength of 3000 N / mm A 2 to 4100 N / mm A 2, determined according to ASTM D2969, and having a carbon content of 0.79 wt% to 1.10 wt%.

[0017] "Raw yarn" means a multifilament yarn that is spun without any twisting and is therefore not yet hot-drawn and impregnated. A "textile reinforcement" means a reinforcement made of one, two, or more multifilament yarns made of a textile material, such as PA 6.6 or PET, where the multifilament yarn(s) have already undergone the process of hot-drawing, including impregnation, and twisting. In a textile reinforcement made of two or more multifilament yarns, the two or more multifilament yarns can be end-twisted together to form a cord.

[0018] Physical measurement parameters, in particular physical measurement parameters of the textile reinforcements and / or the multifilament yarns of the textile reinforcements and / or the raw yarns of the multifilament yarns and / or the steel reinforcements and / or the steel filaments of the steel reinforcements, can be determined before embedding the respective reinforcement in the respective reinforcement layer of the pneumatic vehicle tire.

[0019] The force-strain data for determining the tensile strength per unit of the raw yarns or the textile reinforcements, as well as the tensile strength per unit of 4% elongation of the raw yarns or the textile reinforcements, are each determined according to ASTM D885. The hot shrinkage of the raw yarns or the textile reinforcements is determined at 180 °C under a pre-tension with an exposure time of two minutes. For PET, the pre-tension is 0.01 cN / dtex. For PA 6.6, the pre-tension is 0.05 cN / dtex.

[0020] The tensile strength of the steel filaments is determined according to ASTM D2969.

[0021] Amazingly, it has been found that precisely the targeted combination of the aforementioned reinforcement layers with high-strength reinforcement members results in a tire that, despite the comparatively thin reinforcement layers of the various components (carcass, belt bandage, and belt), still offers sufficient robustness against special stresses, such as improper use. What is important here is that the reinforcement members of the at least one bandage layer and the at least one carcass layer, as well as the at least one belt layer, are made of high-strength raw yarns or steel filaments, as well as the shrinkage behavior of the raw yarns made of PA 6, which is adapted to the requirements of the bandage layer.6 cords and the shrinkage behavior of the raw yarns made of PET cords, which is adapted to the requirements of the carcass ply, still ensure sufficient robustness of the tire against special stresses, such as improper use, even with a comparatively low fineness of the individual reinforcements. This applies particularly to the particularly stressed head area, where the aforementioned components are arranged overlapping one another in the radial direction. In particular, the aforementioned reinforcement layers can be arranged overlapping one another in the radial direction.

[0022] The high-strength design of the reinforcements of the bandage layer, the carcass layer and the belt layer enables the comparatively thin combination of reinforcement layers to improve rolling resistance while maintaining sufficient robustness.

[0023] The reinforcement layers of the components can thus be made comparatively thin, further reducing the rolling resistance of the pneumatic vehicle tire. At the same time, the reinforcement layers still meet the specific requirements of the respective components—carcass, belt, or belt bandage—of the pneumatic vehicle tire, and their combination enables a tire with sufficient robustness to withstand special stresses, such as improper use of the pneumatic vehicle tire.

[0024] It has been shown that the pneumatic vehicle tire according to the invention still has sufficient robustness against special stresses, such as improper use, while still having further improved rolling resistance.

[0025] An advantageous embodiment is provided by the fact that the raw yarn made of PA 6.6 has a fineness-related strength which, at an elongation of 4%, lies in a range of 13.5 cN / tex to 16.0 cN / tex.

[0026] The textile reinforcements of the tire layer thus exhibit a comparatively high modulus of elasticity for PA 6.6 at an elongation of 4%, while also offering advantageous fatigue resistance with regard to alternating compressive and flexural stresses. Thus, the elongation required for tire production is maintained up to approximately 3%, while higher forces must be applied at higher elongations, which is advantageous for the tire's high-speed operation.

[0027] An advantageous embodiment is provided by the textile reinforcements of the bandage layer being designed as first bandage reinforcements, wherein the first bandage reinforcements are each formed from exactly one of the multifilament PA 6.6 yarns. The first bandage reinforcements have a tenacity-related strength ranging from 20.5 cN / tex to 28.0 cN / tex at an elongation of 4%, and a twist factor a' of the twist of the multifilament PA 6.6 yarn of 30 to 40.

[0028] Despite the resulting particularly thin tire layer, the tire's durability and robustness are sufficiently ensured. The pneumatic vehicle tire constructed in this way is lightweight and offers favorable rolling resistance.

[0029] The twist factor a' of the twist of a multifilament yarn is defined as (twist of the multifilament yarn [t / m]) ■ (fineness of the multifilament yarn [tex] / 1000)1 / 2 The twist factor a' is a measure of the twist per meter of the multifilament yarn, related to the total fineness of the multifilament yarn.

[0030] It is advantageous if the twist factor a' of the multifilament PA 6.6 yarn of the first bandage reinforcement lies in a range of 25 to 40. This twist factor a' represents a favorable compromise regarding fatigue resistance and strength. A lower twist factor a' would be disadvantageous with regard to fatigue resistance, while a higher twist factor would result in lower strength of the textile reinforcement.

[0031] The first bandage reinforcement is made from exactly one of the PA 6.6 multifilament yarns and thus has the PA 6.6 x1 construction. It is advisable for the PA 6.6 multifilament yarn to have a fineness of 700 dtex.

[0032] An advantageous embodiment is provided in that the textile strength members of the bandage layer are designed as second bandage strength members, wherein the second bandage strength members are each designed as a cord of the PA 6.6 x 2 construction. The second bandage strength members have a fineness-related maximum tensile force of more than 74 cN / tex, a fineness-related strength which, at an elongation of 4%, is in a range of 12 cN / tex to 20 cN / tex, a hot shrinkage of 4.0% to 7.0%, determined at 180 °C under a pretension of 0.05 cN / dtex with an exposure time of two minutes, and a twist factor a of the final twist of the cord of 100 to 250.

[0033] The use of such high-strength reinforcements allows for comparatively thin reinforcement layers. Such a tire is characterized by low weight and thus advantageous rolling resistance while simultaneously offering sufficient durability and robustness.

[0034] The twist factor a of the final twist of a cord is defined as (Twist of the final twist [t / m]) ■ (Fineness of the cord [tex] / 1000) 1 / 2 The twist factor a is a measure of the twist per meter of the cord, related to the total fineness of the cord.

[0035] It is advantageous if the twist factor a of the final twist of this cord of the PA 6.6 x2 construction of the second drum strength member is in a range of 100 to 250. This twist factor represents a favorable compromise between fatigue resistance and strength. A lower twist factor would be disadvantageous in terms of fatigue resistance, while a higher twist factor would result in lower strength of the cord.

[0036] The second bandage reinforcement is designed as a PA 6.6 x2 cord and is thus made of exactly two PA 6.6 multifilament yarns, which are end-twisted together to form the cord. It is advisable for the two PA 6.6 multifilament yarns to each have a count of 470 dtex or 700 dtex.

[0037] An advantageous embodiment is provided in that the raw yarn made of PET has a fineness-related strength which, at an elongation of 4%, lies in a range of 25 cN / tex to 37 cN / tex.

[0038] The use of such a high-strength material for the reinforcement of the carcass enables a tire with advantageous rolling resistance and at the same time sufficient robustness.

[0039] An advantageous embodiment is provided in that the textile strength members of the carcass ply are designed as first carcass strength members, wherein the first carcass strength members are each designed as a cord of the PET x 2 construction. The first carcass strength members have a fineness-related maximum tensile force of more than 68 cN / tex, a fineness-related strength which, at an elongation of 4%, is in a range of 15 cN / tex to 25 cN / tex according to ASTM D885, a hot shrinkage of less than 2.8%, preferably less than 2.5%, determined at 180 °C under a pretension of 0.01 cN / dtex with an exposure time of 2 minutes and a twist factor a of the final twist of the cord of 150 to 250.

[0040] The first carcass reinforcements are characterized by their high-strength properties combined with advantageous shrinkage behavior. Such a tire is characterized by low weight and thus advantageous rolling resistance, while simultaneously offering sufficient durability and robustness.

[0041] The first carcass reinforcement is constructed as a PET x2 cord, consisting of exactly two PET multifilament yarns that are end-twisted together to form the cord. It is advisable for the two PET multifilament yarns to each have a fineness of 1100 dtex.

[0042] It is advantageous if the twist factor a of the final twist of this cord of construction PET x 2 is in a range of 150 to 250. This twist factor represents a favorable compromise between fatigue resistance and strength. A lower twist factor would be disadvantageous in terms of fatigue resistance, while a higher twist factor would result in lower strength of the cord.

[0043] It is expedient if the textile reinforcements of the bandage layer are designed as first bandage reinforcements of the PA 6.6 x 1 construction and the textile reinforcements of the carcass layer are designed as first carcass reinforcements of the PET x 2 construction.

[0044] However, it is also expedient if the textile reinforcements of the bandage layer are designed as second bandage reinforcements of the PA 6.6 x 2 construction, and the textile reinforcements of the carcass layer are designed as first carcass reinforcements of the PET x 2 construction. An advantageous embodiment is provided by the multifilament yarn made of PA 6.6 having a fineness of 450 dtex to 750 dtex, preferably 470 dtex to 700 dtex. Such a fineness of the multifilament yarn made of PA 6.6 has proven particularly suitable for use in the tire according to the invention.

[0045] An advantageous embodiment is provided by the multifilament PET yarn having a fineness of 1000 dtex to 1200 dtex, preferably 1100 dtex. Such a fineness of the multifilament PET yarn has proven particularly suitable for use in the tire according to the invention.

[0046] An advantageous embodiment is provided by the steel filaments of the reinforcements of the belt layer having a diameter of 0.20 mm to 0.42 mm, preferably 0.20 mm to 0.32 mm or 0.33 mm to 0.40 mm. A diameter of 0.20 mm to 0.42 mm has proven particularly suitable for use in the tire according to the invention.

[0047] For a strength member of the belt layer formed from exactly one steel filament, a diameter of 0.33 mm to 0.42 mm, preferably 0.35 mm to 0.40 mm, has proven to be particularly suitable.

[0048] For a strength member of the belt layer formed from two or more of the steel filaments, a diameter of 0.20 mm to 0.35 mm, preferably from 0.20 mm to 0.32 mm, particularly preferably from 0.20 mm to 0.30 mm, has proven to be particularly suitable.

[0049] An advantageous embodiment is provided by the reinforcements of the belt layer being designed as first belt reinforcements, each formed from exactly one of the steel filaments. The steel filaments each have a tensile strength of 3400 N / mm A 2 to 4100 N / mm A 2, and the belt layer has a strength of 30 kN / dm to 50 kN / dm. Such a tire is characterized by low weight and thus favorable rolling resistance, while simultaneously providing sufficient durability and robustness.

[0050] The steel filament preferably has a diameter of 0.33 mm to 0.42 mm, particularly preferably 0.33 mm, 0.35 mm or 0.40 mm.

[0051] Another advantageous embodiment is provided by the reinforcements of the belt layer being designed as second belt reinforcements. The second belt reinforcements are formed from two or three or more steel filaments. The second belt reinforcements preferably have the construction x2 or 1+2 or 1+3, particularly preferably the construction x2 or 1+2. The steel filaments each have a tensile strength of 3000 N / mm A 2 to 4000 N / mm A 2. The belt layer preferably has a strength of 30 kN / dm to 75 kN / dm.

[0052] Such a tire is characterized by its low weight and thus advantageous rolling resistance while at the same time being sufficiently durable and robust.

[0053] The diameter of the steel filaments of the second belt reinforcements is preferably 0.20 mm to 0.35 mm, particularly preferably 0.20 mm to 0.32 mm, particularly preferably 0.20 mm to 0.30 mm. It is expedient if the reinforcements of constructions 1 + 2 have a steel filament diameter of 0.29 mm.

[0054] An advantageous embodiment is provided in that the PET and / or the PA 6.6 is formed entirely or partially from the respective bio-based polymer.

[0055] It is advantageous if the PET is made entirely or partially from bio-based PET. It is advantageous if the PA 6.6 is made entirely or partially from bio-based PA 6.6.

[0056] In the context of the present invention, the term “bio-based polymer” means a polymer which is composed entirely or at least partially of monomers whose starting monomers were obtained directly from biomass.

[0057] The polymer can be made entirely from monomers derived from biomass, meaning that, within the scope of the invention, 100% by weight of the starting monomers are directly derived from biomass. This optimizes the pneumatic vehicle tire according to the invention, particularly with regard to sustainability, while simultaneously offering excellent properties.

[0058] However, the polymer can also be produced only partially from monomers from biomass, especially if some of the monomers underlying the polymer are not accessible from biomass. In the context of the present invention, "at least partially produced from biomass" means that more than 0 wt.% of the starting monomers were obtained directly from biomass. As a result, the pneumatic vehicle tire according to the invention is optimized with regard to the flexibility and sustainability required, depending on the availability of starting materials, while simultaneously offering excellent properties.

[0059] As is known to those skilled in the art, the proportion of bio-based materials, i.e. the proportion of renewable raw materials in the polymer, can be determined according to ASTM D 6866 (C-14 method).

[0060] However, the PA 6.6 and / or the PET can also be formed from non-biobased PA 6.6 and / or non-biobased PET, i.e., within the scope of the invention, none of the starting monomers of the respective polymer were directly obtained from biomass. It can be conventional, in particular petroleum-based, PA 6.6 and / or conventional, in particular petroleum-based, PET. An advantageous embodiment is provided by the PET and / or the PA 6.6 being formed entirely or partially from the respective recycled polymer.

[0061] It is advantageous if the PET is made entirely or partially from recycled PET.

[0062] It is advantageous if the PA 6.6 is made entirely or partially from recycled PA 6.6.

[0063] In the context of the present invention, the term "recycled polymer" refers to a polymer obtained by at least one recycling process. The recycling process can be any recycling process known to the person skilled in the art, such as, in particular, chemical and / or mechanical recycling.

[0064] The starting materials for recycling are mainly bottles, clothing and yarn waste.

[0065] In the context of the present invention, mechanical recycling processes also include temperature treatments, such as remelting.

[0066] In the context of this invention, chemical recycling refers to any type of chemical processing of waste and the subsequent recovery of new products or raw materials from it. This can also mean complete chemical degradation into molecules in which the material source, i.e., the chemical nature of the waste, is no longer immediately recognizable, and subsequent synthesis from these molecules into polymers, which are then used as recycled polymers in the respective multifilament yarn.

[0067] Furthermore, industrial yarn waste can also be recycled and used as material for the textile strength carrier, as is particularly the case with PET and PA 6.6. Depending on the type and similarity of the yarn waste to the required materials, chemical and / or mechanical recycling is appropriate. Recycled PET, which is produced in particular through mechanical recycling of bottles, differs from original (virgin) PET in terms of additives, such as the isophthalic acid (IPA) content. These additives, particularly IPA, are found, for example, in PET bottles in particular. Recycled PET, which is obtained through mechanical recycling of yarn waste, also has a higher polydispersity index compared to reference yarns that have not been recycled.

[0068] The PA 6.6 and / or the PET may be formed entirely or partially from original (virgin) PA 6.6 and / or original (virgin) PET.

[0069] To ensure reliable adhesion of the textile reinforcements to the rubber, it is advisable to provide the textile reinforcements with an adhesive impregnation, e.g., with a dip in a one- or two-bath process. The dip can be a known RFL dip (resorcinol formaldehyde latex) or an environmentally and health-friendly RFL-free alternative, as described, for example, in DE 102014211362 A1, WO 2019015792 A1, EP 3702521 A1, EP 3702522 A1, or EP 3702523 A1.

[0070] The carcass of the pneumatic vehicle tire comprises one or more carcass plies according to the invention. A particularly simple carcass is achieved when all reinforcement layers of the carcass are designed as carcass plies according to the invention. The carcass is preferably single-layer and formed by exactly one carcass ply according to the invention.

[0071] The belt bandage of the pneumatic vehicle tire has one or more bandage layers according to the invention. A particularly simple belt bandage is achieved when all reinforcement layers of the belt bandage are designed as bandage layers according to the invention. The belt bandage is preferably single-layered and formed by exactly one bandage layer according to the invention. The belt of the pneumatic vehicle tire has one, two, or more belt layers according to the invention. The belt preferably has two belt layers designed according to the invention, the strength members of which are arranged intersecting at an angle and with stiffening opposite to the circumferential direction. A particularly simple belt is achieved when all reinforcement layers of the belt are designed as belt layers according to the invention.

[0072] The pneumatic vehicle tire is manufactured in particular in a manner known to the person skilled in the art using devices known to the person skilled in the art.

[0073] In particular, an unvulcanized green body of an unvulcanized vehicle tire comprising the reinforcement layers according to the invention, including all described embodiments, is first prepared by stacking the corresponding components, which comprise unvulcanized rubber mixtures, on top of one another. The green body is then vulcanized.

[0074] The pneumatic vehicle tire according to the invention is preferably a tire for a passenger car, a van, or a light truck. It is preferably a radial tire.

[0075] The invention encompasses all advantageous embodiments, which are reflected, among other things, in the patent claims. In particular, the invention also encompasses embodiments resulting from the combination of different features with varying degrees of preference, so that a combination of a first feature designated as "preferred" with another feature designated, for example, as "particularly preferred" is also encompassed by the invention.

[0076] In the following, the invention is explained in more detail using two exemplary embodiments according to the invention, without, however, being limited to these.

[0077] The two pneumatic vehicle tires designed according to the invention, in particular radial

[0078] The design comprises a carcass formed from a carcass ply, a belt arranged radially outside the carcass and formed from two belt layers, and a belt bandage formed by at least one bandage layer resting radially on the belt from the outside and covering at least the belt edges. The carcass ply, the belt layers and the bandage layer each have strength members which are embedded in rubber material within the respective layer, arranged parallel and spaced from one another, wherein the strength members of the bandage layer are textile strength members, each formed from at least one multifilament yarn made of polyamide 6.6 (PA 6.6), wherein the strength members of the carcass ply are textile strength members, each formed from at least one multifilament yarn made of polyethylene terephthalate (PET), and wherein the strength members of the belt layers are each formed from at least one steel filament.The strength members of the two belt layers are arranged at an angle and with stiffening opposite to the circumferential direction.

[0079] The two pneumatic vehicle tires according to the invention have the following reinforcements in their reinforcement layers (in the order of bandage layer, carcass layer, belt layer):

[0080] First pneumatic vehicle tire: PA6.6 700x1, PET 1100x2, steel 1x0.35 Second pneumatic vehicle tire: PA6.6470x2, PET1100x2, steel 1 +2x0.29

[0081] The textile reinforcements of the bandage layer of the two pneumatic vehicle tires are characterized by the fact that the multifilament yarn made of PA 6.6 has a fineness of 100 dtex to 1500 dtex, that the raw yarn made of PA 6.6 of the multifilament yarn made of PA 6.6 has a fineness-related maximum tensile strength of greater than 87 cN / tex, determined according to ASTM D885, and a hot shrinkage of greater than 6%, determined at 180°C under a pretension of 0.05 cN / dtex with an exposure time of two minutes.

[0082] Furthermore, the raw yarn made of PA 6.6 exhibits a tenacity-related strength ranging from 13.5 cN / tex to 16.0 cN / tex at an elongation of 4%. The textile reinforcements of the carcass ply of both pneumatic vehicle tires are characterized by the fact that the multifilament PET yarn has a tenacity of 1100 dtex, that the raw yarn made of the multifilament PET yarn has a tenacity-related maximum strength of 83.5 cN / tex, determined according to ASTM D885, and a hot shrinkage of 7.2%, determined at 180 °C under a pretension of 0.01 cN / dtex with an exposure time of two minutes. Furthermore, the raw yarn made of PET has a tenacity-related strength of 32.1 cN / tex at an elongation of 4%.

[0083] Furthermore, the textile reinforcements of the carcass ply of the two pneumatic vehicle tires designed according to the invention are each designed as first carcass reinforcements, wherein the first carcass reinforcements are designed as cords of the PET x 2 construction, wherein the multifilament yarns made of PET have a fineness of 1100 dtex. The first carcass reinforcements have a fineness-related maximum tensile force of 70.9 cN / tex, a fineness-related strength which, at an elongation of 4%, is 20.1 cN / tex according to ASTM D885, a hot shrinkage of 2.2%, determined at 180°C under a pretension of 0.01 cN / dtex with an exposure time of 2 minutes, and a twist factor a of the final twist of the cord of 195.

[0084] The strength members of the belt layers of the two pneumatic vehicle tires are characterized by the fact that the steel filament has a tensile strength of 3000 N / mm A 2 to 4100 N / mm A2, determined according to ASTM D2969, and having a carbon content of 0.79 wt% to 1.10 wt%.

[0085] The first pneumatic vehicle tire according to the invention, in particular of radial design, is characterized with regard to the tire layer in that the textile reinforcements of the tire layer according to the invention are designed as first tire reinforcements, wherein the first tire reinforcements are each formed from exactly one of the multifilament yarns made of PA 6.6. The multifilament yarn made of PA 6.6 has a fineness of 700 dtex. Furthermore, the first tire reinforcements have a fineness-related strength that, at an elongation of 4%, lies in a range from 20.5 cN / tex to 28.0 cN / tex, and a twist factor a' of the twist of the multifilament yarn made of PA 6.6 of 25 to 40.

[0086] The first pneumatic vehicle tire according to the invention is characterized with regard to the belt layers in that the strength members of the belt layers are each formed from exactly one of the steel filaments and that the steel filament has a diameter of 0.35 mm and a tensile strength of 3742 N / mm A 2 and that the belt layer has a strength of 34 kN / dm.

[0087] The second pneumatic vehicle tire according to the invention is characterized with regard to the tire ply in that the reinforcements of the tire ply according to the invention are designed as second tire reinforcements. They have the PA 6.6 x2 construction, with the multifilament yarns made of PA 6.6 having a fineness of 470 dtex. The second tire reinforcements have a tensile strength of more than 74 cN / tex, a tensile strength of 12 cN / tex to 20 cN / tex at an elongation of 4%, a heat shrinkage of 4.0% to 7.0%, determined at 180°C under a pretension of 0.05 cN / dtex with an exposure time of two minutes, and a twist factor a of the final twist of the cord of 100 to 250.

[0088] The second pneumatic vehicle tire according to the invention is characterized with regard to the belt layers in that the strength members of the belt layers are each formed from three of the steel filaments and have the construction 1 + 2. The steel filaments have a diameter of 0.29 mm and a tensile strength of 3593 N / mm A 2. The belt layer has a strength of 64 kN / dm.

[0089] It has been shown that the two pneumatic vehicle tires designed according to the invention, thanks to the combination of high-strength materials in the reinforcement layers of the carcass, the belt bandage, and the belt, still exhibit sufficient robustness against extreme stresses despite the comparatively low material usage. At the same time, the comparatively low material usage further improves rolling resistance.

Claims

Patent claims 1. A pneumatic vehicle tire comprising a carcass having a carcass ply, a belt arranged radially outside the carcass and having a belt ply, and a belt bandage resting radially outside on the belt and having a bandage ply, wherein the carcass ply, the belt ply and the bandage ply each have reinforcements which are embedded in rubber material arranged parallel to and spaced from one another within the respective ply, • wherein the reinforcements of the bandage layer are textile reinforcements, each formed from at least one multifilament yarn of polyamide 6.6 (PA 6.6), • wherein the reinforcements of the carcass ply are textile reinforcements, each formed from at least one multifilament yarn of polyethylene terephthalate (PET), and • wherein the strength members of the belt layer are each formed from at least one steel filament, characterized in that the multifilament yarn made of PA 6.6 has a fineness of 100 dtex to 1500 dtex, that the raw yarn made of PA 6.6 of the multifilament yarn made of PA 6.6 • a tensile strength of greater than 87 cN / tex, determined according to ASTM D885, and • has a heat shrinkage of more than 6%, determined at 180°C under a pre-tension of 0.05 cN / dtex for two minutes of exposure, that the multifilament yarn made of PET has a fineness of 50 dtex to 2500 dtex, that the raw yarn made of PET of the multifilament yarn made of PET • a tensile strength of > 70 cN / tex, determined according to ASTM D885, and • has a heat shrinkage of less than 8%, measured at 180 °C under a pre-tension of 0.01 cN / dtex for two minutes of exposure, and that the steel filament • a tensile strength of 3000 N / mm A 2 to 4100 N / mm A 2, determined according to ASTM D2969, and • has a carbon content of 0.79 wt% to 1.10 wt%.

2. Pneumatic vehicle tire according to at least one of the preceding claims, characterized in that the raw yarn made of PA 6.6 has a fineness-related strength which, at an elongation of 4%, is in a range from 13.5 cN / tex to 16.0 cN / tex.

3. Pneumatic vehicle tire according to at least one of the preceding claims, characterized in that the textile reinforcements of the bandage layer are designed as first bandage reinforcements, wherein the first bandage reinforcements are each formed from exactly one multifilament yarn made of PA 6.6 of the at least one multifilament yarn made of PA 6.6 and that the first bandage reinforcements • a tenacity related to the fineness, which lies at an elongation of 4% in a range of 20.5 cN / tex to 28.0 cN / tex, and • have a twist factor a' of the twist of the multifilament yarn made of PA 6.6 of 25 to 40.

4. Pneumatic vehicle tire according to at least one of claims 1 to 2, characterized in that the textile reinforcements of the bandage layer are designed as second bandage reinforcements, wherein the second bandage reinforcements are each designed as a cord of the construction PA 6.6 x 2 and • a maximum tensile strength of more than 74 cN / tex, • a tenacity related to the fineness, which at an elongation of 4% lies in a range of 12 cN / tex to 20 cN / tex, • a heat shrinkage of 4.0% to 7.0%, determined at 180 °C under a pre-tension of 0.05 cN / dtex with an exposure time of two minutes, and • have a twist factor a of the final twist of the cord of 100 to 250.

5. Pneumatic vehicle tire according to at least one of the preceding claims, characterized in that the raw yarn made of PET has a fineness-related strength which, at an elongation of 4%, lies in a range from 25 cN / tex to 37 cN / tex.

6. Pneumatic vehicle tire according to at least one of the preceding claims, characterized in that the textile reinforcements of the carcass ply are designed as first carcass reinforcements, wherein the first carcass reinforcements are each designed as a cord of the construction PET x 2 and • a maximum tensile strength of more than 68 cN / tex, • have a tenacity-related strength which, at an elongation of 4%, is in the range of 15 cN / tex to 25 cN / tex according to ASTM D885, • a heat shrinkage of less than 2.8%, preferably less than 2.5%, determined at 180 °C under a pre-tension of 0.01 cN / dtex with 2 min exposure time and • have a twist factor a of the final twist of the cord of 150 to 250.

7. Pneumatic vehicle tire according to at least one of the preceding claims, characterized in that • that the multifilament yarn made of PA 6.6 has a fineness of 450 dtex to 750 dtex, preferably 470 dtex to 700 dtex, and / or • that the multifilament yarn made of PET has a fineness of 1000 dtex to 1200 dtex, preferably 1100 dtex.

8. Pneumatic vehicle tire according to at least one of the preceding claims, characterized in that the steel filament has a diameter of 0.20 mm to 0.42 mm, preferably of 0.20 mm to 0.32 mm or of 0.33 mm to 0.42 mm.

9. Pneumatic vehicle tire according to at least one of the preceding claims, characterized in that the strength members of the belt layer are designed as first belt strength members, that the first belt strength members are each formed from exactly one of the steel filaments, that the steel filaments each have a tensile strength of 3400 N / mm A 2 to 4100 N / mm A 2 and that the belt layer has a strength of in particular 30 kN / dm to 50 kN / dm.

10. Pneumatic vehicle tire according to at least one of claims 1 to 8, characterized in that the strength members of the belt layer are designed as second belt strength members, that the second belt strength members are each formed from two or three or more steel filaments of the steel filaments, preferably forming the construction x2 or 1+2 or 1+3, particularly preferably forming the construction x2 or 1+2, that the steel filaments have a tensile strength of 3000 N / mmA 2 to 4000 N / mm A 2 and that the belt layer has a strength of in particular 30 kN / dm to 75 kN / dm.

11. Pneumatic vehicle tire according to at least one of the preceding claims, characterized in that the PET and / or the PA 6.6 is formed wholly or partly from the respective bio-based polymer.

12. Pneumatic vehicle tire according to at least one of the preceding claims, characterized in that the PET and / or the PA 6.6 is formed wholly or partly from the respective recycled polymer.

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