High load capacity tyre comprising moulded elements

Abstract

The invention relates to a tyre of the high load capacity type for a passenger vehicle, comprising a smooth reference surface (44) and at least one moulded element (46) that is recessed and at least one moulded element that is projecting relative to the smooth reference surface (44). A maximum thickness Emax, the maximum depth Pmax of each recessed moulded element (46) and / or the maximum height Hmax of each projecting moulded element satisfy Emax^(0.4) x Pmax ≤ 1.1 and Emax^(0.4) x Hmax ≤ 1.1, Pmax and Hmax being expressed in mm. Emax Is the maximum distance between the axially outermost reinforced layer (36) and the smooth reference surface (44). Emax is less than or equal to 3.0 mm.

Description

High-load-capacity pneumatic system including molded components

[0001] The present invention relates to a tire. A tire is defined as a band designed to form a cavity by cooperating with a support element, for example a rim, this cavity being capable of being pressurized to a pressure greater than atmospheric pressure. A tire according to the invention has a substantially toroidal structure of revolution around a principal axis of the tire.

[0002] The advent of electric and hybrid passenger vehicles has led to an increase in vehicle weight, primarily due to the relatively significant weight of the batteries, which is roughly proportional to the vehicle's range. For example, increasing the range of an electric vehicle requires increasing the size of the batteries and, consequently, the vehicle's weight.

[0003] Simply put, it is currently estimated that one kilometer of electric range increases the vehicle's weight by one kilogram. Therefore, to achieve a range of 500 kilometers, the weight of a vehicle with an internal combustion engine needs to be increased by approximately 500 kg. Equipping such vehicles requires tires capable of supporting a very high load.

[0004] We know of a tire for passenger vehicles capable of carrying a relatively high load. This tire is marketed under the MICHELIN™ brand in the Pilot Sport 4 range and has a size of 255 / 35R18. This tire is available in an EXTRA-LOAD version (abbreviated XL) as defined by the ETRTO 2019 standard manual, and in this EXTRA-LOAD version, it has a load index of 94. This means that, at a pressure of 290 kPa, the tire is capable of carrying a load of 670 kg. This load capacity is relatively high compared to a tire of the same size designated as STANDARD LOAD (abbreviated SL), which has a load index of 90 and is capable of carrying a load of 600 kg at a pressure of 250 kPa.

[0005] In order to be placed on the market, such a tire must pass regulatory tests. For example, in Europe, the tire must pass the load / speed performance test described in Annex VII of UNECE Regulation No. 30.

[0006] However, whether in its EXTRA-LOAD version, and even more so in its STANDARD LOAD version, such a tire is not capable of carrying the additional load corresponding to the batteries required to achieve the desired range. Therefore, tire manufacturers have had to develop new solutions to meet this new need.

[0007] One solution being considered by tire manufacturers is, for a vehicle Given the circumstances, using larger tires would allow for a greater load capacity. Thus, a given vehicle could be equipped with tires having a higher load index. For example, a vehicle equipped with the tires described above in their EXTRA LOAD version could be fitted with 275 / 35R19 tires in their EXTRA-LOAD version, which have a load index of 100 and are capable, at a pressure of 290 kPa, of carrying a load of 800 kg, significantly more than the 670 kg load.

[0008] On the one hand, such an increase in tire size necessarily leads to either a reduction in the vehicle's interior space or an increase in the vehicle's exterior dimensions, which in both cases is undesirable for reasons of vehicle habitability and compactness.

[0009] On the other hand, such an increase in tire size leads to a redesign of the vehicle chassis, which for obvious cost reasons is also undesirable.

[0010] Finally, such an increase in tire size, particularly in nominal section width, leads to an increase in external noise generated by the tire as well as an increase in rolling resistance, which is also undesirable if one wishes to reduce noise pollution and the energy consumption of the vehicle.

[0011] Therefore, another solution considered by tire manufacturers is to increase the recommended inflation pressure for a given size and version of a tire. Indeed, the higher the pressure, the greater the load the tire can carry.

[0012] However, using a relatively high recommended pressure stiffens the tire and leads to a loss of comfort for the vehicle's passengers, which is obviously not desired by some car manufacturers in cases where passenger comfort takes priority over the load that can be carried.

[0013] Therefore, tire manufacturers decided to create a new type of tire. This new type is now known as HIGH LOAD CAPACITY in the ETRTO 2021 standard manual. This new type guarantees that the load a tire of a given size can carry is greater than that of a tire of the same size in its EXTRA-LOAD version. For the 255 / 35R18 size, the HIGH LOAD CAPACITY tire has a load index of 98, indicating that it can carry a load of 750 kg at a pressure of 290 kPa.

[0014] It was noted, during the use of these HIGH LOAD type tires CAPACITY, the initiation of cracks on the sidewall surface of these tires, particularly in a radially superior portion located radially between, on the one hand, the tire's equator and, on the other hand, a normal to the inner surface passing through a circumferential separation line between the sidewall and the crown. It was noted that the appearance of these cracks occurred particularly when driving through a deep pothole or over a significant bump in the road surface, when abruptly mounting a curb, when using a pressure significantly lower than the recommended pressure, or when using a load significantly exceeding the maximum load.

[0015] Such cracks, while not dangerous to the tire user, detract from the tire's appearance and therefore its aesthetics. Furthermore, they can cause unnecessary anxiety for the tire user.

[0016] The invention aims to provide a tire capable of carrying a greater load than existing tires while reducing, or even eliminating, the risk of sidewall cracking.

[0017] Thus, the invention relates to a passenger vehicle tire comprising a crown, two beads, two sidewalls connecting each bead to the crown, at least one of the sidewalls comprising at least one reinforced layer including reinforcing elements embedded in a polymer matrix, the sidewall or each sidewall comprising a radially upper portion radially situated between: the equator of the tire, and a normal to the inner surface passing through a circumferential separation line between the sidewall and the crown, the radially upper portion having an outer face comprising: a smooth reference surface, at least one molded recessed element and / or at least one molded protruding element relative to the smooth reference surface, the tire (10) being of the HIGH LOAD CAPACITY type according to the ETRTO 2021 standard manual, a maximum thickness Emax,a maximum depth Pmax of the or each molded hollow element of the radially superior portion relative to the smooth reference surface and / or a maximum height Hmax of the or each molded protruding element of the radially superior portion relative to the smooth reference surface satisfy Emax, A (0.4) x Pmax < 1,1 and Emax A (0.4) x Hmax < 1.1, Emax, Pmax and Hmax being expressed in mm, with Emax being the maximum distance measured in the radially upper portion along a line normal to the inner surface between: - the axially outer surface passing through the axially outermost point of each reinforcing element of the or each portion of the or each axially reinforced layer in the radially upper portion, and - the smooth reference surface, Emax being less than or equal to 3.0.

[0018] According to the invention, the tire is a passenger vehicle tire. Such a tire is, for example, defined in the ETRTO 2021 (European Tyre and Rim Technical Organisation) standard manual. Such a tire generally has, on at least one of its sidewalls, a marking conforming to the marking in the ETRTO 2021 standard manual indicating the tire size in the form X / Y a VU p, where X designates the nominal section width, Y designates the nominal aspect ratio, a designates the construction and can be R or ZR, V designates the nominal rim diameter, U designates the load index, and α designates the speed symbol.

[0019] By increasing the load index of the tire of the invention compared to the load index of a tire of the same size in its EXTRA-LOAD version, the invention makes it possible to increase the load capacity of the assembled tire without altering the interior space, compactness, or comfort of the vehicle on which it is used. Indeed, since the size of the tire according to the invention is identical to that of the tire in its EXTRA-LOAD version, the assembled tire is no larger than the tire in its EXTRA-LOAD version. A tire according to the invention may bear a distinctive marking allowing it to be distinguished from its STANDARD LOAD version and its EXTRA-LOAD version, for example, a marking of the type HL (for HIGH LOAD) or XL+ (for EXTRA LOAD +). Such a marking is notably disclosed in the ETRTO 2021 standard manual, page 3 of the General Notes - Passenger Car Tyres section.Examples of HIGH LOAD CAPACITY type tire dimensions are also disclosed in the ETRTO 2021 standard manual, page 44, paragraph 9.1 of the section Passenger Car tyres - Tyres with metric designation.

[0020] A high-load capacity tire can be characterized by its load index LI, where LI > Ll'+1, and LI' is the load index of an extra-load tire of the same size, according to the ETRTO 2021 standard manual. The load index Ll' is the load index of an extra-load tire of the same size, i.e., the same nominal section width and the same aspect ratio. In nominal appearance, the same structure (R and ZR being considered identical) and the same nominal rim diameter. The load index Ll' is given by the ETRTO 2021 standard manual, specifically in the section entitled Passenger Car Tyres - Tyres with Metric Designation, pages 22 to 43. Depending on the size, we will have LI=U'+1, LI=LI'+2, LI=LI'+3 or even LI=LI'+4. In most embodiments, Ll'+1 < Ll < LI'+4, and even LI'+2 < Ll < LI'+4.

[0021] The inventors of this invention understood that, due to the relatively high loads that high-load capacity tires are subjected to, the radially upper portion of the sidewall is subjected to very high stresses, particularly during high-stress events such as those described above. This radially upper portion comprises the part of the outer sidewall face that, during high-stress events, will have the smallest radius of curvature and therefore a high concentration of stresses. This portion of the outer sidewall face is easily determined, for example, by inflating the tire to a pressure less than or equal to its nominal pressure and applying a load significantly greater than the nominal load, for example, a load greater than or equal to 120% of its nominal load, the pressure and nominal load being as indicated in the ETRTO 2021 standard manual.

[0022] The inventors also understood that these very strong stresses are located in the vicinity of areas of the flank exhibiting a strong local variation in thickness.

[0023] Thus, the inventors determined that by reducing these local variations in thickness which are essentially present in the vicinity of the molded hollow or protruding elements present on the external face of the radially external portion, for example in the form of marking, the risk of cracking in the side was reduced or even eliminated.

[0024] The inventors also observed that the greater the maximum thickness Emax of high-load capacity tires, the more susceptible the sidewalls were to the development of the cracks described above. Therefore, the inventors determined a relationship that allows either limiting the maximum depth Pmax or the maximum height Hmax of the molded elements for a given maximum thickness Emax, or limiting the maximum thickness Emax for a given maximum depth Pmax and / or maximum height Hmax of the molded elements.

[0025] In addition to satisfying the relationship determined by the inventors, the maximum thickness Emax will be reduced as much as possible to reduce the risk of cracking, this risk being, as explained previously, all the higher the maximum thickness Emax is important.

[0026] Molded or protruding components include, but are not limited to, marking elements, nipples, and / or vent valves, and are preferably selected from among these components. Marking elements include, but are not limited to, regulatory markings, decorative markings, and tire tracking markings, and are preferably selected from among these components. Regulatory markings include, but are not limited to, those required by various regulations and include, in particular, the tire brand, its commercial designation, and the DOT number. Decorative markings include markings whose primary function is to enhance the tire's appearance. Tire tracking markings include, in particular, coded matrix symbols (QR codes).

[0027] Ventilation nipples are molded protruding elements with a generally tapered shape, formed by the creep of the elastomeric compound that forms the outer surface of the tire within vents in a mold during the tire molding process. Similarly, vent valves are molded recessed elements with a generally well-like shape, formed by the tire molding process.

[0028] The circumferential separation line between the sidewall and the crown is generally a molded line, as it corresponds to the separation between two mold elements used for molding the sidewall and the crown. When multiple circumferential lines are present, the circumferential separation line is the innermost radially located one. In the absence of a molded line, the separation line between the sidewall and the crown is an imaginary circumferential line located at: a radial distance equal to 65% of the tire's sidewall height (H) from the innermost radial end of the tire for tires where H < 95, and a radial distance equal to 70% of the tire's sidewall height (H) from the innermost radial end of the tire for tires where H > 95.

[0029] The sidewall height H is defined by H=SW x AR / 100 with SW the nominal section width and AR the nominal aspect ratio of the tire, for example as indicated in the ETRTO 2021 standard manual.

[0030] The smooth surface is the tire surface free of molded recesses or protrusions and following the curvature of the tire's outer face without any abrupt local variations. This smooth surface serves as a reference for determining the maximum depth Pmax and / or the maximum height Hmax. Thus, the smooth surface of The reference surface is the assembly formed by the smooth surface passing through the tire surface, free of any molded recesses or protrusions, and by an imaginary surface following the curvature of the tire's outer face and extending continuously from the smooth surface, disregarding any molded recesses or protrusions. The smoothness of the reference surface is characterized by the fact that its roughness is significantly lower than that of the molded element, and in any case, undetectable by touch. The smooth reference surface is generally characterized by a brightness much greater than that of the molded element, which must contrast with this smooth reference surface.

[0031] A molded element is defined as a component formed from the rest of the tire sidewall during the tire molding process. Each molded recess or protrusion is continuous. Thus, when two recessed or protrusion elements are at least partially joined and connected by another recessed or protrusion element, these connected elements are considered a single molded recessed or protrusion element. Conversely, when two recessed or protrusion elements are completely separated by a portion of the smooth reference surface, these two recessed or protrusion elements are considered two distinct molded elements.

[0032] The maximum depth Pmax of the hollow molded element is the maximum value of the distances measured between the smooth reference surface and the various points on the bottom of the hollow molded element. Similarly, the maximum height Hmax of the protruding molded element is the maximum value of the distances measured between the smooth reference surface and the various points on the external surface of the protruding molded element.

[0033] Preferably, the radially upper portion extends circumferentially and continuously around the entire circumference of the tire.

[0034] Other molded features, either recessed or protruding, may be present on the tire sidewall outside the radially upper portion. These other molded features may not conform to the relationship determined by the inventors. Indeed, outside the radially upper portion, the stresses are lower, resulting in a reduced, or even nonexistent, risk of cracking.

[0035] The maximum thickness Emax of the radially upper portion is the maximum value of the thicknesses of the radially upper portion, the thickness being able to be constant or variable.

[0036] For each reinforced layer of the side or sides, a continuous surface, called the axially external surface (AES) of said layer, is defined, passing through the most axially external point of each reinforcement element, as well as a continuous surface, called the axially internal surface (AIS) of said layer, passing through the most axially internal point of each reinforcement element.

[0037] In some embodiments, the radially upper portion comprises a single, outermost axially reinforced layer extending over its entire radial height. In other embodiments, the radially upper portion comprises several outermost axially reinforced layers along its radial dimension. In these other embodiments, the SAE axially outer surface used to calculate the maximum distance Emax is the axially outer surface of each portion of each outermost axially reinforced layer at the radial dimension at which the thickness between the axially outer surface and the smooth surface is measured.

[0038] By reinforcing element, we mean an element enabling the mechanical reinforcement of the polymer matrix in which this reinforcing element is intended to be embedded.

[0039] Preferably, the reinforcing element is wire-like, meaning that the element has a length at least 10 times greater than the longest dimension of its cross-section, regardless of the cross-section's shape: circular, elliptical, oblong, polygonal, and in particular rectangular, square, or oval. In the case of a rectangular cross-section, the wire-like reinforcing element is in the form of a strip.

[0040] The matrix is ​​said to be polymeric because it is based on a polymeric composition, this polymeric composition being able to include one or more polymers, for example chosen from thermoplastic polymers, thermosetting polymers, elastomers, thermoplastic elastomers, but also fillers and other components usually used in the field of tire compositions, in particular compositions for embedding reinforcement elements.

[0041] The inner surface defines the internal cavity of the tire. The internal cavity is designed to be pressurized by the inflation gas once the tire is mounted on a mounting support, for example a rim.

[0042] The external surface is the surface of the tire in contact with air at atmospheric pressure and visible from the outside of the tire.

[0043] The tire according to the invention has a substantially toroidal shape around an axis of revolution substantially coinciding with the tire's axis of rotation. This axis of revolution defines three directions commonly used by those skilled in the art: an axial direction, a circumferential direction and a radial direction.

[0044] Axial direction refers to the direction substantially parallel to the axis of revolution of the tire, that is, the axis of rotation of the tire.

[0045] By circumferential direction, we mean the direction which is substantially perpendicular to both the axial direction and to a radius of the tire (in other words, tangent to a circle whose center is on the axis of rotation of the tire).

[0046] By radial direction, we mean the direction along a radius of the tire, that is to say any direction intersecting the axis of rotation of the tire and substantially perpendicular to this axis.

[0047] By median plane of the tire (noted M), we mean the plane perpendicular to the axis of rotation of the tire which is located at mid-axial distance of the two ribs and passes through the axial midpoint of the crown reinforcement.

[0048] The equatorial circumferential surface of a tire is defined as the combination of planes passing, in each meridian plane, through the equator (denoted E) of the tire and perpendicular to the median plane and the radial direction. The equator of the tire is, in a meridian plane (a plane perpendicular to the circumferential direction and parallel to the radial and axial directions), the axis parallel to the axis of rotation of the tire and located equidistant between the outermost radial point of the tread intended to be in contact with the ground and the innermost radial point of the tire intended to be in contact with a support, for example a rim, the distance between these two points being equal to H.

[0049] By meridian plane, we mean a plane parallel to and containing the axis of rotation of the tire and perpendicular to the circumferential direction.

[0050] Radially inside and radially outside refer to the area closest to and further from the tire's axis of rotation, respectively. Axially inside and axially outside refer to the area closer to and further from the tire's median plane, respectively.

[0051] The bead is the portion of the tire designed to allow the tire to be attached to a mounting surface, such as a wheel with a rim. Each bead is specifically designed to make contact with a hook on the rim, enabling it to be secured.

[0052] Any range of values ​​designated by the expression "between a and b" represents the range of values ​​from more than a to less than b (i.e., bounds a and b excluded) while any range of values ​​designated by the expression "from a to b" means the range of values ​​from a to b (i.e., including the strict bounds a and b).

[0053] In embodiments that reduce the risk of cracking, the radially upper portion bearing the outer face comprises one or more hollow molded elements and / or one or more protruding molded elements, where one or at least a portion of the hollow molded element(s) or one or at least a portion of the protruding molded element(s) is such that Emax A (0.4) x Pmax > 1,1 and Emax A(0.4) x Hmax > 1.1. In these embodiments, the invention is applied to only a part of the molded elements of the radially upper portion.

[0054] In embodiments that further reduce the risk of cracking, the radially upper portion bearing the outer face comprises one or more hollow molded elements and / or one or more protruding molded elements, where all or part of the hollow molded elements and / or all or part of the protruding molded elements is such that Emax A (0.4) x Pmax < 1,1 and Emax A (0.4) x Hmax < 1.1. In these embodiments, the invention is applied to all the molded elements of the radially upper part.

[0055] In certain embodiments which reduce the risk of cracking, given the relatively small size of the nipples and vent valves, the hollow and / or protruding molded elements concerned by the invention are the hollow and / or protruding molded elements excluding the nipples and vent valves.

[0056] In some embodiments, the molded recesses and / or protrusions relevant to the invention include molded recesses and / or protrusions comprising lines oriented in the circumferential direction. Lines are understood to mean the lines delimiting the molded recesses and / or protrusions. Thus, a letter is delimited by several lines oriented in different directions, one or more of these lines being oriented in the circumferential direction. Other examples include markings in the form of grooves that may be oriented in the circumferential direction.

[0057] In advantageous embodiments that limit the risk of cracking, Emax A (0.4) x Pmax < 0.9 and Emax A (0.4) x Hmax < 0.9, more preferably Emax A (0.4) x Pmax < 0.8 and Emax A(0.4) x Hmax < 0.8 and even more preferably Emax x Pmax < 0.6 and Emax x Hmax < 0.6.

[0058] The tires are intended for passenger vehicles as defined in the ETRTO standard manual, 2021. Such a tire has a cross-section in a meridional plane characterized by a section height H and a nominal section width or bead size S as defined in the ETRTO standard manual, 2021 Optionally, the H / S ratio, expressed as a percentage, is at most 90 and at least 20, and the nominal section width S is at least 225 mm and at most 385 mm. Furthermore, the hook diameter D, defining the diameter of the tire mounting rim, is optionally at least 16 inches and at most 24 inches. Finally, also optionally, the load index L1 ranges from 98 to 116.

[0059] In advantageous embodiments that limit the risk of cracking, the radially upper portion of said or each sidewall comprises an elastomeric composition bearing the external surface of said radially upper portion of said sidewall and having a modulus at 10% extension less than or equal to 10 MPa, preferably 5 MPa, and more preferably ranging from 1 MPa to 5 MPa. Elastomeric compositions with a lower modulus at 10% extension are preferred when the tire presents a high risk of cracking.

[0060] The elastomeric composition bearing the outer surface allows for the identification of the elastomeric composition in contact with air at atmospheric pressure and visible from the outside of the tire. Thus, in embodiments where the radially upper portion of the sidewall comprises several elastomeric compositions arranged axially side by side, the modulus at 10% extension of the outermost axially extending composition bearing the outer surface is characterized.

[0061] The elastomeric composition bearing the external surface is based on one or more elastomers. It may also include fillers and other components commonly used in tire compounds.

[0062] Regarding the modulus at 10% extension, commonly called MA10, this is the elastic modulus of the mixture measured during a uniaxial tensile test at an elongation value of 0.1 (i.e., 10% elongation, expressed as a percentage). A constant uniaxial tensile speed is applied to the specimen, and its elongation and the stress are measured. The measurement is performed using an INSTRON tensile testing machine at a temperature of 23°C and a relative humidity of 50% (ISO 23529 standard). The measurement and data processing conditions for determining elongation and stress are as described in standard NF ISO 37:2012-03. The stress is determined for an elongation of 0.1, and the modulus of elasticity under tension at 10% elongation is calculated by dividing this stress value by the elongation value.A person skilled in the art will know how to choose and adapt the dimensions of the test specimen according to the amount of mixture accessible and available, particularly in the case of test specimen sampling in the tire.

[0063] In optional embodiments, Pmax is less than or equal to 0.8 mm, preferably 0.5 mm, and Hmax is less than or equal to 0.8 mm, preferably 0.5 mm. In addition to satisfying the relationship determined by the inventors, the maximum depth Pmax and / or the maximum height Hmax should be reduced as much as possible to eliminate any risk of cracking.

[0064] In advantageous but optional embodiments, Pmax is greater than or equal to 0.3 mm and Hmax is greater than or equal to 0.3 mm. Since the contrast of the molded elements is all the more important as the maximum depth Pmax and / or the maximum height Hmax increases, a sufficiently large maximum depth Pmax and / or maximum height Hmax will be preferred.

[0065] In advantageous but nevertheless optional embodiments, Emax is greater than or equal to 1.0 mm and preferably ranges from 1.5 mm to 2.5 mm.

[0066] Advantageously, the tire has a sidewall height H defined by H = SW x AR / 100, where SW is the nominal section width and AR is the nominal aspect ratio of the tire, and a load index Ll satisfying 0.72 < H / LI < 0.95, preferably 0.72 < H / LI < 0.90, with SW, AR, and Ll being defined according to the ETRTO 2021 standard manual. Thus, the invention is preferentially applied to tires likely to flex significantly because they have a relatively high load index for a relatively small sidewall height for that load index. Indeed, in these cases, the radially outer portion of the sidewall forms a relatively short hinge subjected to significant flexing, particularly in the high-stress cases described above, and therefore highly susceptible to cracking.

[0067] The nominal section width SW, the nominal aspect ratio AR and the load index Ll are indicated in particular on the dimension marking inscribed on the sidewall of the tire and conform to the manual of the ETRTO 2021 standard.

[0068] In a first configuration, the tire includes a carcass reinforcement comprising at least one carcass layer anchored in each bead, the crown comprising a crown reinforcement, the carcass layer anchored in each bead extending radially in each sidewall and axially in the crown radially internal to the crown reinforcement, the or each portion of the outermost axially reinforced layer or layers being formed by at least one portion of the carcass layer anchored in each axially outermost bead in the radially superior portion.

[0069] In a first variant of the first configuration, the carcass frame comprises a single layer of carcass anchored in each bead.

[0070] In some embodiments of this first variant, the layer of carcass anchored in each bead forms a wrap around a circumferential reinforcing element of each bead such that an axially inner portion of the carcass layer anchored in each bead is arranged axially inside an axially outer portion of the carcass layer anchored in each bead and such that each axial end of the carcass layer anchored in each bead is arranged radially outside each circumferential reinforcing element: the outermost portion or portions of the axially reinforced outermost layer or layers is formed by at least one portion of the axially inner portion in the radially upper portion, and / or the outermost portion or portions of the axially reinforced outermost layer or layers is formed by at least one portion of the axially outer portion in the radially upper portion.

[0071] In other embodiments of this first variant, each bead comprises an axially internal circumferential reinforcing element arranged axially inside the carcass layer and an axially external circumferential reinforcing element arranged axially outside the carcass layer, for example as described in WO2021 / 123522.

[0072] In a second variant of the first configuration, the carcass frame comprises first and second carcass layers anchored in each bead.

[0073] In some embodiments of this second variant, the first carcass layer forms a wrap around a circumferential reinforcing element of each bead such that an axially inner portion of the first carcass layer is arranged axially inside an axially outer portion of the first carcass layer and such that each axial end of the first carcass layer is arranged radially outside each circumferential reinforcing element, and each axial end of the second carcass layer is arranged radially inside each axial end of the first layer.

[0074] In a first variant of these embodiments, each axial end of the second carcass layer is arranged axially between the inner and outer axial portions of the first carcass layer, the outermost portion or portions of the outermost axially reinforced layer or layers being formed by at least one portion of the second carcass layer in the radially upper portion. In this first variant, the second carcass layer is arranged radially at the outside of the first layer of carcass in the top.

[0075] In a second embodiment, each axial end of the second carcass layer is arranged axially within each axially inner portion of the first carcass layer, the outermost portion(s) of the axially reinforced layer(s) being formed by at least one portion of the first carcass layer in its radially upper portion. In this embodiment, the second carcass layer is arranged radially within the first carcass layer at the apex and axially within the first carcass layer in each flank.

[0076] In a third embodiment, each axial end of the second carcass layer is arranged axially outside each axially outer portion of the first carcass layer, the outermost portion(s) of the axially reinforced layer(s) being formed by at least one portion of the second carcass layer in its radially upper portion. In this embodiment, the second carcass layer is arranged radially outside the first carcass layer at the top and axially outside the first carcass layer in each flank.

[0077] In other embodiments of this second variant, each bead comprises a plurality of circumferential reinforcing elements, at least a portion of each first and second carcass layer being arranged axially between at least two circumferential reinforcing elements of the plurality of circumferential reinforcing elements, for example as described in WO2021 / 123522.

[0078] In a second configuration, the tire includes: - a carcass reinforcement comprising at least one carcass layer anchored in each bead, the apex comprising a apex reinforcement, the carcass layer anchored in each bead extending radially in each flank and axially in the apex radially internally to the apex reinforcement, - a side reinforcement layer arranged axially outside the carcass reinforcement, the outermost portion or portions of the outermost axially reinforced layer or layers being formed by at least one portion of the side reinforcement layer in the radially superior portion.

[0079] Unlike a carcass layer, which is anchored in each rib, the side reinforcement layer is not anchored in each rib. Thus, each radially inner end of the side reinforcement layer is arranged radially outside each rib. The side reinforcement layer extends at least radially in each flank and presents: - a radially inward end arranged radially inside the equator of the tire, and - a radially external end arranged radially outside the equator of the tire.

[0080] In certain embodiments where the carcass layer or first carcass layer forms a coil, each axial end of said carcass layer is arranged radially inside the equator of the tire and, even more preferably, arranged at a radial distance of 30 mm or less from an inner radial end of each circumferential reinforcement element of each bead. Arranging each axial end of the carcass layer or first carcass layer inside the equator of the tire significantly reduces the mass of the carcass reinforcement. Furthermore, the vast majority of rims currently used for passenger car tires have J-type hooks with a height that is, in all cases, less than 30 mm.The highly preferential arrangement of each axial end in an area roughly corresponding radially to the rim hook provides mechanical protection for each axial end. Indeed, if each axial end were positioned radially too far above each circumferential reinforcement element of each bead, that is, at a radial distance strictly greater than 30 mm from the inner radial end of each circumferential reinforcement element, each axial end would then be located in a flexible area of ​​the tire subjected to excessive stresses, stresses which are particularly significant in the case of a high-load capacity tire.

[0081] In other embodiments in which the carcass layer or the first carcass layer forms a coil, each axial end of said carcass layer is arranged radially outside the equator of the tire. Advantageously, in these other embodiments, each axial end of the carcass layer or the first carcass layer is arranged very preferably axially inside an axial end of the or at least one of the top layers of the crown reinforcement.

[0082] Optionally, the carcass layer or layers anchored in each bead is axially delimited by two axial ends of said carcass layer and includes carcass reinforcement elements extending axially from one axial end to the other axial end of the carcass layer.

[0083] Optionally, each carcass reinforcement element extends along a main direction forming, with the circumferential direction of the tire, an angle in absolute value greater than or equal to 60°, preferably ranging from 80° to 90°.

[0084] In some embodiments, the apex includes an apex reinforcement comprising a working reinforcement comprising a radially inner working layer and a radially outer working layer arranged radially outside the radially inner working layer.

[0085] Optionally, each working layer is axially delimited by two axial ends of said working layer and includes working reinforcement elements extending axially from one axial end to the other axial end of said working layer, each substantially parallel to the other.

[0086] Optionally, each working reinforcement element extends along a main direction forming, with the circumferential direction of the tire, an angle, in absolute value, strictly greater than 10°, preferably ranging from 15° to 50° and more preferably ranging from 20° to 35°.

[0087] Preferably, in embodiments in which the working reinforcement comprises a radially innermost working layer and a radially outermost working layer arranged radially outside the radially innermost layer, the principal direction in which each working reinforcement element of the radially innermost working layer extends and the principal direction in which each working reinforcement element of the radially outermost working layer extends form, with the circumferential direction of the tire, angles of opposite orientations.

[0088] Optionally, the top reinforcement includes a shrink-fit reinforcement axially delimited by two axial ends of the shrink-fit reinforcement and comprising at least one shrink-fit reinforcement element circumferentially wound helically so as to extend axially between the axial ends of the shrink-fit reinforcement.

[0089] Preferably, the shrink-fit armature is arranged radially outside the working armature.

[0090] Preferably, the or each reinforcement element of the shrink-fit extends along a principal direction forming, with the circumferential direction of the tire, an angle, in absolute value, less than or equal to 10°, preferably less than or equal to 7° and more preferably less than or equal to 5°.

[0091] Preferably, the frame reinforcement element(s), working element(s) and swaging element(s) is a wire reinforcement element.

[0092] In advantageous embodiments, the molded element is The hollow and / or each protruding molded element has a brightness L*1 ranging from 6 to 15, and preferably from 8 to 10, while the smooth reference surface has a brightness L*2 greater than or equal to 18, and preferably from 18 to 30. These advantageous embodiments make it possible to obtain a relatively high contrast even when the maximum depth Pmax and / or the maximum height Hmax is relatively small. Indeed, generally speaking, and all other things being equal, the smaller the maximum depth Pmax and / or the maximum height Hmax, the lower the contrast of the molded element with respect to the smooth reference surface.

[0093] This method ensures that the molded element presents a strong contrast against the smooth reference surface. Brightness refers to the parameter that characterizes a surface's ability to reflect light. Brightness is expressed here on a scale from 0 to 100, in accordance with the L*a*b* color model adopted in 1976 by the International Commission on Illumination (CIE). A value of 100 represents white or total reflection; a value of 0, black or total absorption. The brightness values ​​L*1 and L*2 are determined using a spectrophotometer, such as the KONICA-MINOLTA CM 700D. This instrument is positioned over the area whose brightness is to be measured, and the brightness of that area is directly measured.This measurement is performed using SCI mode (including specular reflection mode) set to a 10° angle and a D65 light setting (CIE standard). To improve the determination of the L*2 luminance, multiple measurements can be taken on the tire, and an average luminance of the smooth reference surface can be calculated.

[0094] In advantageous embodiments, the or each hollow molded element and / or the or each protruding molded element comprises a texture comprising a plurality of elements protruding from the bottom of said hollow molded element and / or said protruding molded element.

[0095] Optionally, the protruding elements of the plurality of protruding elements are independent unit elements distributed throughout the texture at a density of at least one element per square millimeter. In one variant, the plurality of protruding elements comprises strands, each strand having an average cross-section between 0.003 mm² 2 and 1 mm 2 Examples of strands are described in EP1954463, EP2204296, and EP2483088. In another variant, the plurality of protruding elements includes bumps such as those found on tires marketed under the Dunlop brand and the V EURO designation. In other variants, the plurality of protruding elements includes stars as known on tires marketed under the Bridgestone brand and the commercial name POTENZA SPORT.

[0096] Optionally, the protruding elements of the plurality of protruding elements are substantially parallel lamellae, with a lamella spacing in the texture of at most 0.5 mm, each lamella having an average width between 0.03 mm and 0.25 mm. Examples of lamellae are described, for example, in EP2483088 and W02012131089.

[0097] The invention will be better understood upon reading the following description, given solely by way of non-limiting example and made with reference to the drawings in which: Figure 1 is a view, in a meridian section plane, of a tire according to a first embodiment of the invention, Figure 2 is a side view of an external face of the tire of Figure 1 along the direction H-H' indicated on Figure 1, Figures 3 and 4 are detail views respectively along the meridian section planes III-IH' and IV-IV' indicated on Figure 2 illustrating a radially external portion of the sidewall of the tire of Figure 1, and Figures 5 to 9 are views similar to those of Figure 1 of tires respectively according to second, third, fourth, fifth and sixth embodiments.

[0098] In the figures, we have represented a coordinate system X, Y, Z corresponding to the usual directions respectively axial (Y), radial (Z) and circumferential (X) of a tire or a mounted assembly.

[0099] Figure 1 shows a tire according to the invention, designated by the general reference numeral 10. The tire 10 has a substantially toroidal shape around an axis of revolution substantially parallel to the axial direction Y. The tire 10 is intended for a passenger vehicle and has dimensions 255 / 35 R20. In the various figures, the tire 10 is shown in its new condition, i.e., having not yet been driven on.

[0100] The tire 10 includes a crown 12 comprising a tread 14 intended to come into contact with the ground during rolling and a crown reinforcement 16 extending into the crown 12 in the circumferential direction X. The tire 10 also includes an internal sealing layer 18 for an inflation gas intended to delimit an internal cavity with a mounting support for the tire 10 once the tire 10 is mounted on the mounting support, for example a rim, this cavity being intended to be pressurized by the inflation gas. The layer internal sealing 18 carries an internal surface 19 of the tire 10.

[0101] The top reinforcement 16 includes a working reinforcement 20 and a shrinkage reinforcement 22. The working reinforcement 20 includes at least one working layer and here includes two working layers comprising a radially inner working layer 24 and a radially outer working layer 26 arranged radially outside the radially inner working layer 24.

[0102] The shrink frame 22 includes at least one shrink layer and here includes a shrink layer 28.

[0103] The top reinforcement 16 is arranged radially inside the tread 14. Here, the shrink-fit reinforcement 22, here the shrink-fit layer 28, is arranged radially outside the working reinforcement 20 and is therefore radially interposed between the working reinforcement 20 and the tread 14.

[0104] The tire 10 comprises two sidewalls 30 extending radially inwards from the apex 12. The tire 10 further comprises two beads 32 radially inwards from the sidewalls 30. Each sidewall 30 connects each bead 32 to the apex 12.

[0105] The tire 10 includes a carcass reinforcement 34. The crown reinforcement 16 is arranged radially between the tread 14 and the carcass reinforcement 34. The carcass reinforcement 34 includes at least one carcass layer 36, here a single carcass layer 36, anchored in each bead 32. The carcass layer 36 extends radially in each sidewall 30 and axially in the crown 12 radially internally to the crown reinforcement 16.

[0106] The carcass layer 36 anchored in each bead 32 forms a wrap around a circumferential reinforcing element 33 of each bead 32 such that an axially inner portion 3611, 3621 of the carcass layer 36 anchored in each bead 32 is arranged axially inside an axially outer portion 3612, 3622 of the carcass layer 36 anchored in each bead 32, and such that each axial end 361, 362 axially delimiting the carcass layer 36 anchored in each bead 32 is arranged radially outside each circumferential reinforcing element 33. Each axial end 361, 362 of the carcass layer 36 anchored in each bead 32 is arranged radially inside the equator E of the tire.More specifically, each axial end 361, 362 of the carcass layer 36 anchored in each bead 32 is arranged at a radial distance RNC less than or equal to 30 mm from a radially inner end 331 of each circumferential reinforcing element 33 of each bead 32. Here RNC=23 mm.

[0107] Each working layer 24, 26, shrink-fit layer 28, and carcass layer 36 comprises a polymer matrix, here elastomeric, in which one or more reinforcing elements of the corresponding layer are embedded, here wire reinforcement elements. Each wire reinforcement element of the shrink-fit, working, and carcass layers is, for example, identical to those described in WO2021250331 A1.

[0108] The shrink-fit reinforcement 22, here the shrink-fit layer 28, is axially delimited by two axial ends 281, 282. The shrink-fit reinforcement 22 comprises one or more circumferentially helically wound wire shrink-fit reinforcement elements extending axially from one axial end to the other of the shrink-fit reinforcement 22 along a principal direction D0 forming, with the circumferential direction X of the tire 10, an angle AF, in absolute value, less than or equal to 10°, preferably less than or equal to 7° and more preferably less than or equal to 5°. Here, AF=-5°.

[0109] The radially inner working layer 24 is axially delimited by two axial ends 241, 242. The radially inner working layer 24 comprises wire reinforcement elements extending axially from one axial end to the other, substantially parallel to each other along a principal direction D1. Similarly, the radially outer working layer 26 is axially delimited by two axial ends 261, 262. The radially outer working layer 26 comprises wire reinforcement elements extending axially from one axial end to the other, substantially parallel to each other along a principal direction D2. Each principal direction D1, D2 forms angles AT1 and AT2 of opposite orientations with the circumferential direction X of the tire 10.Each principal direction D1, D2 forms, with the circumferential direction X of the tire 10, an angle respectively AT1, AT2, in absolute value, strictly greater than 10°, preferably ranging from 15° to 50° and more preferably ranging from 20° to 35°. Here, AT1=-26° and AT2=+26°.

[0110] The carcass layer 36 includes carcass wire reinforcement elements extending axially from one axial end to the other along a principal direction D3 forming with the circumferential direction X of the tire 10, an angle AC, in absolute value, greater than or equal to 60°, preferably ranging from 80° to 90° and here AC=+90°.

[0111] Each sidewall 30 bears a marking indicating the size of the tire 10, as well as a speed rating and a speed code. In this case, the tire 10 has a nominal section width SW of 255, a nominal aspect ratio AR of 35, and a nominal rim diameter of 20. The tire 10 therefore has a sidewall height H defined by SW x AR / 100, here equal to 89. According to the invention, the marking also includes a load index Ll, such that Ll > Ll'+1 with Ll' being the load index of an EXTRA LOAD tire of the same size according to the ETRTO 2019 standard manual. Preferably, Ll'+1 < Ll < LI'+4, and even LI'+2 < Ll < LI'+4. A tire with a size of 255 / 35R20 in its EXTRA LOAD version has a load index of 97, as indicated on page 36 of the Passenger Car Tyres - Tyres with Metric Designation section of the ETRTO 2019 standard manual. Thus, the load index Ll of tire 10 is such that Ll > 98, preferably 98 < Ll < 101, and even 99 < Ll < 101, and here LI=100. This load index of 100 corresponds to the load index of a HIGH LOAD CAPACITY tire of size 255 / 35R20 as indicated in the ETRTO 2021 manual. Thus, tire 10 is indeed of the HIGH LOAD CAPACITY type.

[0112] Tire 10 is such that 0.72 < H / LI < 0.95, preferably 0.72 < H / LI < 0.90 and here H / LI=0.89.

[0113] With reference to Figures 1 to 4, each sidewall 30 comprises a radially upper portion 38 situated radially between the equator E of the tire and a normal N to the inner surface 19 passing through a circumferential line 40 separating each sidewall 30 and the apex 12. The radially upper portion 38 has an outer face 42 visible in Figure 2 comprising a smooth reference surface 44 as well as recessed molded elements 46 and protruding molded elements 47. In the example illustrated in Figure 2, the recessed molded elements 46 include a regulatory marking “R20” and the protruding molded elements 47 include a marking “TIRE Co” as well as a decorative marking in the form of grooves comprising lines oriented in the circumferential direction.

[0114] Each side 30 also includes molded elements 48 arranged outside the outer face 42 of the radially upper portion 38.

[0115] As illustrated in Figures 3 and 4, the radially upper portion 38 comprises an elastomeric composition 50 bearing the external surface 52 of the radially upper portion 38. The elastomeric composition 50 has a modulus MA10 at 10% extension less than or equal to 10 MPa, preferably 5 MPa, and more preferably ranging from 1 MPa to 5 MPa. In this case, MA10 = 3 MPa. Examples of compositions compatible with these MA10 modulus values ​​are the reference composition T1 of WO2019 / 097175, the comparative example A described in WO2018 / 100080, and the compositions described in WO2018 / 091841 and WO2019 / 229323.

[0116] Each flank 30 comprises a reinforced layer including reinforcing elements embedded in a polymer matrix, here the carcass layer 36 comprising the carcass reinforcing elements 360 embedded in a polymer matrix 363. The carcass layer 36 comprises an axially external SAE surface passing through the the outermost axial point of each carcass reinforcement element 360 and an axially internal surface SAI passing through the outermost axial point of each carcass reinforcement element 360. The carcass layer 36 is separated from the adjacent compositions with which its polymer matrix 363 is in contact by axially internal interfaces IAI and external interfaces IAE.

[0117] At any point on the internal surface 19 of the radially upper portion 38, a thickness EP is measured along a normal line N1 to the internal surface 19 at said point. The thickness EP is the distance measured along each normal line N1 between, on the one hand, the axially outer surface SAE of a portion PC of the outermost axially reinforced layer in the radially upper portion 38, here of a portion PC of the axially inner portion 3611 of the carcass layer 36 in the radially upper portion 38, and, on the other hand, the smooth reference surface 44. The maximum value of the thicknesses measured in the radially upper portion 38 is the maximum thickness Emax. Emax is less than or equal to 3.0 mm and greater than or equal to 1.0 mm and preferably ranges from 1.5 mm to 2.5 mm. Here, Emax = 2.4 mm.

[0118] With reference to Figure 3, the hollow molded element 46 has a maximum depth Pmax relative to the smooth reference surface 44. Pmax is less than or equal to 0.8 mm, preferably 0.5 mm and greater than or equal to 0.3 mm. Here Pmax = 0.5 mm.

[0119] With reference to Figure 4, each molded protruding element 47 has a maximum height Hmax relative to the smooth reference surface 44. Hmax is less than or equal to 0.8 mm, preferably 0.5 mm and greater than or equal to 0.3 mm. Here, Hmax = 0.5 mm.

[0120] Thus, Pmax, Hmax and Emax satisfy Emax A (0.4) x Pmax < 1,1 and Emax A (0.4) x Hmax < 1.1, preferably Emax A (0.4) x Pmax < 0.9 and Emax A (0.4) x Hmax < 0.9, more preferably Emax A (0.4) x Pmax < 0.8 and Emax A (0.4) x Hmax < 0.8. Here Emax A (0.4) x Hmax = Emax A(0.4) x Pmax = 0.7. In other embodiments, Emax and / or Hmax and Pmax can be reduced so that Emax A (0.4) x Pmax < 0.6 and Emax A (0.4) x Hmax < 0.6.

[0121] We will now describe, with reference to Figures 5 to 9, tires according to second, third, fourth, fifth, and sixth embodiments respectively. Elements analogous to those in the preceding figures are designated by identical reference numerals.

[0122] Unlike the tire in the first embodiment, the carcass reinforcement 36 of the tire 10 in the second embodiment of Figure 5 comprises first and second carcass layers 36, 37 anchored in each bead 32. The first carcass layer 36 forms a wrap around each circumferential reinforcing element 33 of each bead 32 such that an axially inner portion 3611, 3621 of the first carcass layer 36 is arranged axially inside an axially outer portion 3612, 3622 of the first carcass layer 36 and such that each axial end 361, 362 of the first carcass layer 36 is arranged radially outside each circumferential reinforcing element 33. Each axial end 371, 372 of the second carcass layer 37 is arranged radially inside each axial end of the first layer 361, 362 and is arranged axially between the axially inner and outer portions 3611, 3612 and 3621, 3622 of the first layer of carcass 36.In this second embodiment, the PC portion of the outermost axially reinforced layer is formed by a PC portion of the second carcass layer 37 in the radially superior portion 38.

[0123] Unlike the tire according to the second embodiment, in the tire 10 according to the third embodiment illustrated in Figure 6, each axial end 371, 372 of the second carcass layer 37 is arranged axially inside each axially inner portion 3611, 3621 of the first carcass layer 36. In this third embodiment, the outermost axially reinforced PC portion of the layer is formed by the PC portion of the first carcass layer 36 in the radially upper portion 38.

[0124] Unlike the tire according to the second embodiment, in the tire 10 according to the fourth embodiment illustrated in Figure 7, each axial end 371, 372 of the second carcass layer 37 is arranged axially outside each axially outer portion 3612, 3622 of the first carcass layer 36. In this fourth embodiment, the PC portion of the outermost axially reinforced layer is formed by the PC portion of the second carcass layer 37 in the radially upper portion 38.

[0125] Unlike the tire according to the first embodiment, in the tire 10 according to the fifth embodiment illustrated in Figure 8, each axial end 361, 362 of the carcass layer 36 anchored in each bead and forming a winding is arranged radially outside the equator E and even more preferably arranged axially inside the axial ends 141, 281 of the working layers 24 and the reinforcement layers 28 of the top reinforcement 16. In this fifth embodiment, the portion PC of the outermost axially reinforced layer is formed by the portion PC of the axially outer portion 3612 of the carcass layer 36 in the radially upper portion 38.

[0126] Unlike the tire according to the first embodiment, in the tire 10 according to the sixth embodiment illustrated in Figure 9, in addition to the carcass reinforcement 34, the tire 10 comprises two sidewall reinforcement layers 39 arranged axially outside the carcass reinforcement 34. Each sidewall reinforcement layer 39 extends at least radially into each sidewall 30 and has a radially inner end 391 arranged radially inside the equator E and a radially outer end 392 arranged radially outside the equator E. Each radially inner end 391 of each sidewall reinforcement layer 39 is arranged radially outside each bead 32 and is therefore not anchored to it.

[0127] COMPARATIVE TESTS

[0128] We ran various tires inflated to a nominal pressure and subjected to a load far exceeding the nominal load of the ETRTO 2021 manual standard during a load / speed performance test described in Annex VII of UNECE Regulation No. 30.

[0129] A first test tire, size HL 255 / 35 R20, which did not conform to the invention, had a maximum thickness Emax of 3.1 mm and molded recessed and protruding elements with a maximum depth Pmax and a maximum height Emax of 0.8 mm. At the end of the test, this first tire exhibited cracks in the radially upper portion of at least one of its sidewalls.

[0130] A second tire, size HL 255 / 35 R20, according to the invention, had a maximum thickness Emax of 2.4 mm and molded hollow and protruding elements with a maximum depth Pmax and a maximum height Emax of 0.8 mm. At the end of the test, this tire according to the invention showed no cracks.

[0131] The invention is not limited to the embodiments described above.

Claims

DEMANDS 1. Passenger vehicle tire (10) comprising a crown (12), two bead ribs (32), two sidewalls (30) connecting each bead (32) to the crown (12), at least one of the sidewalls (30) comprising at least one reinforced layer (36; 37; 39) comprising reinforcing elements embedded (360) in a polymer matrix (363), the sidewall or each sidewall (30) comprising a radially upper portion (38) radially bounded between: the equator (E) of the tire, and a normal (N) to the inner surface (19) passing through a circumferential line (40) separating the sidewall (30) from the crown (12), the radially upper portion (38) bearing an outer face (42) comprising: a smooth reference surface (44), at least one recessed molded element (46) and / or at least one protruding molded element (48) relative to the smooth reference surface (44), characterized in that the tire (10) is of the HIGH LOAD CAPACITY type according to the ETRTO 2021 standard manual,in that a maximum thickness Emax, a maximum depth Pmax of the or each hollow molded element (46) of the radially upper portion (38) relative to the smooth reference surface (44) and / or a maximum height Hmax of the or each protruding molded element (48) of the radially upper portion (38) relative to the smooth reference surface (44) satisfy Emax, A (0.4) x Pmax < 1,1 and Emax A (0.4) x Hmax < 1.1, Emax, Pmax and Hmax being expressed in mm, with Emax being the maximum distance measured in the radially upper portion (38) along a line normal (N1) to the internal surface (19) between: - the axially outer surface (SAE) passing through the axially outermost point of each reinforcing element (360) of the or each portion (PC) of the axially outermost reinforced layer(s) (36; 37; 39) in the radially upper portion (38), and - the smooth reference surface (44), Emax being less than or equal to 3.0 mm.

2. Pneumatic (10) according to the preceding claim, wherein Emax A (0.4) x Pmax < 0.9 and Emax A (0.4) x Hmax < 0.9, more preferably Emax A (0.4) x Pmax < 0.8 and Emax A (0.4) x Hmax < 0.8 and even more preferably Emax A (0.4) x Pmax < 0.6 and Emax A (0.4) x Hmax < 0.

6.

3. Pneumatic (10) according to any one of the preceding claims, wherein the radially upper portion (38) of said or of each sidewall (30) comprises a re elastomeric composition (50) carrying the external surface (52) of said radially superior portion of said flank (30) and having a modulus at 10% extension (MA10) less than or equal to 10 MPa, preferably at 5 MPa and more preferably ranging from 1 MPa to 5 MPa.

4. Pneumatic (10) according to any one of the preceding claims, wherein Pmax is less than or equal to 0.8 mm, preferably 0.5 mm and Hmax is less than or equal to 0.8 mm, preferably 0.5 mm.

5. Pneumatic (10) according to any one of the preceding claims, wherein Pmax is greater than or equal to 0.3 mm and Hmax is greater than or equal to 0.3 mm.

6. Pneumatic (10) according to any one of the preceding claims, wherein Emax is greater than or equal to 1.0 mm and preferably ranges from 1.5 mm to 2.5 mm.

7. Tire (10) according to any one of the preceding claims, having a sidewall height H defined by H=SW x AR / 100 with SW the nominal section width and AR the nominal aspect ratio of the tire, a load index Ll satisfying 0.72 < H / LI < 0.95, preferably 0.72 < H / LI < 0.90, with SW, AR and Ll being defined according to the ETRTO 2021 standard manual.

8. Tire (10) according to any one of claims 1 to 7, comprising a carcass reinforcement (34) comprising at least one carcass layer (36; 37) anchored in each bead (32), the top (12) comprising a top reinforcement (16), the carcass layer (36; 37) anchored in each bead (32) extending radially in each sidewall (30) and axially in the top (12) radially internally to the top reinforcement (16), the or each portion (PC) of the outermost axially reinforced layer or layers (36; 37) being formed by at least one portion (PC) of the carcass layer (36; 37) anchored in each outermost axial bead (32) in the radially upper portion (38).

9. Pneumatic (10) according to claim 8, wherein the carcass reinforcement (34) comprises a single layer of carcass (36) anchored in each bead (32).

10. Pneumatic (10) according to the preceding claim, wherein the carcass layer (36) anchored in each bead (32) forms a wrap around a circumferential reinforcing element (33) of each bead (32) such that an axially inner portion (3611, 3621) of the carcass layer (36) anchored in each bead (32) is arranged axially inside an axially outer portion (3612, 3622) of the carcass layer (36) anchored in each bead (32) and such that each axial end (361, 362) of the carcass layer (36) anchored in each bead (32) is arranged radially outside each circumferential reinforcing element (33): the or each portion (PC) of the outermost axially reinforced layer (36) is formed by at least one portion (PC) of the inner axial portion (3611) in the radially upper portion (38), and / or the or each portion (PC) of the outermost axially reinforced layer (36) is formed by at least one portion (PC) of the outer axial portion (3612) in the radially upper portion (38).

11. Pneumatic (10) according to claim 8, wherein the carcass reinforcement (34) comprises first and second carcass layers (36, 37) anchored in each bead (32).

12. Pneumatic (10) according to the preceding claim, wherein the first carcass layer (36) forms a wrap around a circumferential reinforcing element (33) of each bead (32) such that an axially inner portion (3611, 3621) of the first carcass layer (36) is arranged axially inside an axially outer portion (3612, 3622) of the first carcass layer (36) and such that each axial end (361, 362) of the first carcass layer (36) is arranged radially outside each circumferential reinforcing element (33), and each axial end (371, 372) of the second carcass layer (37) is arranged radially inside each axial end (361, 362) of the first layer (36) And : - axially between the axially inner (3611, 3621) and outer (3612, 3622) portions of the first carcass layer (36), the portion or portions (PC) of the outermost axially reinforced layer or layers (37) being formed by at least one portion (PC) of the second carcass layer (37) in the radially upper portion (38), or - axially within each axially inner portion (3611, 3621) of the first carcass layer (36), the portion or portions (PC) of the outermost axially reinforced layer or layers (36) being formed by at least one portion (PC) of the first carcass layer (36) in the radially upper portion (38), or - axially outside each axially outer portion (3612, 3622) of the first carcass layer (36), the or each portion (PC) of the outermost axially reinforced layer or layers (37) being formed by at least one portion (PC) of the second carcass layer (37) in the radially superior portion (38).

13. Pneumatic (10) according to any one of claims 1 to 7, comprising: - a carcass reinforcement (34) comprising at least one carcass layer anchored in each bead, the apex (12) comprising an apex reinforcement (16), the carcass layer (36) anchored in each bead (32) extending radially in each flank (30) and axially in the apex (12) radially internally to the apex reinforcement (16), - a side reinforcement layer (39) arranged axially outside the carcass reinforcement (34), the or each portion (PC) of the outermost axially reinforced layer or layers (39) being formed by at least one portion (PC) of the side reinforcement layer (39) in the radially superior portion (38).

14. Pneumatic (10) according to any one of the preceding claims, wherein: - the hollow molded element or each one (46) and / or the protruding molded element or each one (48) has a brightness L*1, ranging from 6 to 15, and preferably ranging from 8 to 10, and the smooth reference surface (44) has a brightness L*2, greater than or equal to 18 and preferably ranging from 18 to 30.

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