vehicle tires

Abstract

The invention relates to a vehicle tire with a tread (1) with at least one cut-channel combination (2) which, viewed in cross section, is composed of a radially inner channel region (5) and a radially outer cut-channel region (4), wherein the tread (1) has a radially inner tread layer (1a) and a radially outer tread layer (1b). The radially inner channel region (5) is embedded in the radially inner and the radially outer tread layer (1a, 1b), wherein between the tread layers (1a, 1b) there is a material boundary (1c) adjacent to the radially inner channel region (5) and interrupted by the latter, wherein the first rubber material of which the radially inner tread layer (1a) is made has a CSRI of up to 110 determined according to the following equation: CSRI = 693 k P a ⋅ 100 G ' (100%) [k P a] + 12.3 MP a ⋅ 100 σ (300%) [MP a] 2 CSRI Compound Stone Trapping Retention Index G' (100%) [kPa] Dynamic storage modulus at 100% strain in kilopascals, determined according to ASTM D6601-19 σ (300%) [MPa] Stress value at 300% strain in megapascals, determined according to DIN 53504 (DIN 53504 : 2017-03).

Description

The invention relates to a vehicle tyre, in particular commercial vehicle tyres, having a tread with at least one sipe-channel combination which originates from the tread periphery and has a maximum depth of 70% to 100% of the tread depth in the radial direction and, as viewed in cross section, is composed of a radially inner channel region and a radially outer sipe region having a minimum width of 0.4 mm to 3.0 mm determined parallel to the tread periphery, the radially inner channel region having a greater cross-sectional area than the radially outer sipe region and a maximum width of 150% to 650% of the minimum width determined parallel to the tread periphery, the tread having a radially inner tread layer made of a first rubber material and a radially outer tread layer, adjoining the latter, made of a second rubber material different from the first rubber material.Such a vehicle tire is known, for example, from EP 3 984 775 A1. The vehicle tire has a profiled tread with positive profiles, in which sipe-channel combinations of a radially inner channel region and a radially outer sipe region run with a width of at most 2.5 mm. The tread is composed of three tread layers in the radial direction. In one embodiment, the radially inner channel region is completely in the middle tread layer. The rubber material of the middle tread layer is optimized with respect to the abrasion properties and has a loss factor tan δ which is greater than the loss factor tan δ of the rubber material of the radially innermost tread layer and which is either less than or greater than the loss factor tan δ of the rubber material of the radially outermost tread layer. The tire is said to have good water drainage properties while maintaining high abrasion resistance.A further vehicle tire of the type mentioned at the beginning is known from JP 432 796 2 B2. This vehicle tire has a tread with tread block rows with tread blocks separated from one another by transverse grooves, the tread blocks each being provided centrally with a circumferential groove-sipe combination having a maximum depth of, for example, 7 mm. The groove-groove combination is composed of a radially inner channel region and a radially outer groove region, as viewed in cross section. The radially outer incision region has a constant width of, for example, 0.5 mm and a length of, for example, 4.0 mm in the radial direction. The radially inner channel region has a maximum width of, for example, 1.5 mm and therefore 300% of the width of the radially outer incision region. According to one exemplary embodiment, the tread is composed of a radially outer tread layer and a radially inner tread layer, wherein the radially inner tread layer bulges into the profile blocks in such a way that the radially inner channel region is embedded in the radially inner tread layer. The loss factor at 0° C. of the rubber material of the radially inner tread layer is greater by 5% to 45% than the loss factor at 0° C. of the rubber material of the radially outer tread layer. The vehicle tire should have good wet performance, in particular also as tread wear progresses, and good stiffness properties.WO 2018 / 118023 A1 discloses a commercial vehicle tyre having a tread consisting of a radially inner tread layer and a radially outer tread layer. The rubber material of the radially inner tread layer has a loss factor (max tan (δ)) of at most 0.07 and the rubber material of the radially outer tread layer has a loss factor (max tan (δ)) of at least 0.15. In one exemplary embodiment, grooves are formed in a profile rib of the tread in the region of the radially outer tread layer, said grooves being composed of a radially inner channel region and a radially outer sipe region. The commercial vehicle tire should have uniform abrasion behavior independently of the orientation of the grooves.WO 2017 / 105496 A1 discloses a vehicle tire having a tread composed of a radially outer tread layer and a radially inner tread layer. The tread has grooves which are composed of a radially inner channel region which is circular in cross section and a radially outer sipe region. The radially inner channel region is intended to prevent or suppress the occurrence of cracks in the adjoining rubber material. The rubber material of the radially outer tread layer has an MFTR value according to ISO 6943-2011 (rubber, vulcanized--determination of fatigue under tensile stress) of at least 130,000. The rubber material of the radially inner tread layer has an MFTR value according to ISO 6943-2011 of at least 200 000, is intended to have a high fatigue resistance and is optimized with regard to the crack resistance (resistance to cracking). The radially inner channel region may be located either in the radially inner tread layer or in the radially outer tread layer.US 2021 / 0155046 A1 discloses a pneumatic vehicle tyre having a tread with middle profile blocks, through which grooves are traversed, said grooves being composed in the radial direction of a radially outer sipe region and a radially inner channel region. The tread is composed of a radially outer tread layer and a radially inner tread layer, the grooves being formed exclusively in the radially outer tread layer. The rubber material of the radially outer tread layer should have good abrasion resistance and the rubber material of the radially inner tread layer should have good snow and wet grip properties. The rubber mixtures on which the rubber materials are based contain rubbers having different glass transition temperatures.In vehicle tires of the type mentioned at the beginning, the sipe-channel combinations provided on the tread are advantageous, for example, for rolling resistance. When the tire rolls on the ground, the respective profile elements or profile segments are supported against one another via the radially outer sipe region, which contributes to a reduction in the rolling resistance. The channel region ensures good braking properties on a wet roadway when the tread is abraded. The incision-channel combinations also ensure that the probability of stones penetrating into the region of the channel base is significantly reduced.After corresponding tread abrasion, namely after abrasion via the radially outer incision region, the radially inner channel region is clearly open to the tread periphery, so that the risk of cuts occurring in the rubber material adjoining the radially inner channel region due to foreign bodies, for example ballast stones, is clearly increased.The invention is therefore based on the object of increasing the cut resistance of the tread rubber material with progressive tread abrasion in a vehicle tyre of the type mentioned at the beginning.The stated object is achieved according to the invention in that the radially inner channel region is embedded in the radially inner and the radially outer tread layer and a material boundary adjoining the radially inner channel region and interrupted by the latter is present between the tread layers, wherein the first rubber material, which is made up of the radially inner tread layer, has a CSRI, determined according to the following equation, of up to 110: CSRI compound stone trapping retention index G' (100%) [kPa] dynamic storage modulus at 100% elongation in kilopascals, determined according to ASTM D6601-19 σ (300%) [MPa] stress value at 300% elongation in megapascals, determined according to DIN 53504 (DIN 53504:2017-03).The rubber material of the radially inner tread layer thus has a specific value of an index designed on this side, namely a specific CSRI value. The CSRI value is based on standardized rubber properties (dynamic storage modulus and voltage value). Since the radially outer sipe region already ensures a good stone-repellent effect, the rubber material of the radially inner tread layer can be optimized for its cut resistance at least largely independently of its stone-repellent effect. In particular after abrasion of the tread to the level of the radially inner channel region (abrasion of the complete incision region), the channel region is gradually opened or exposed clearly to the tread periphery, so that the high resistance to cut to foreign bodies of the rubber material of the radially inner tread layer is particularly favorable. The high resistance to cut is ensured by an CSRI value which is limited upward, that is to say by a special coordination of two rubber properties with one another-namely a coordination of the dynamic storage modulus and the voltage value (see equation above).According to a preferred embodiment, the second rubber material, of which the radially outer tread layer consists, has an elongation at break according to DIN 53504 of at least 430%, in particular of at least 440%, preferably of at least 450%, particularly preferably of at least 460%, most preferably of at least 470%. The elongation at break is an indicator of the chip / chunk resistance, wherein the higher the elongation at break ε is R the better the chip / chunk resistance to be expected. It has been found that a rubber material with the stated elongation at break has a significantly improved chip / chunk resistance (see tire tests carried out on this side under item 3), especially even during relatively long journeys on unpaved roads.The cut resistance of the tread rubber material is further improved if the CSRI of the first rubber material is up to 100, preferably up to 90.According to a further preferred embodiment, the stress value at 300% elongation of the first rubber material of which the radially inner tread layer consists is at least 10.5 MPa, in particular at least 11.0 MPa, preferably at least 12.0 MPa, and particularly preferably 12.5 MPa. This contributes to a small CSRI value, so that cut resistance is further improved.It is furthermore advantageous if the dynamic storage modulus at 100% elongation of the first rubber material of which the radially inner tread layer consists is at least 640 kPa, in particular at least 660 kPa, preferably at least 700 kPa, and particularly preferably at least 750 kPa. This also contributes to a small CSRI value, so that cut resistance is further improved.According to a further advantageous embodiment, the second rubber material, which is made up of the radially outer tread layer, has a rebound resilience at a temperature of 23° C., determined according to ISO 4662, of up to 60, in particular of up to 57, preferably of up to 55. This is advantageous for wet brake performance.For the rolling resistance of the vehicle tire, it is advantageous if the second rubber material, which is the radially outer tread layer, has a rebound resilience at a temperature of 70° C., determined according to ISO 4662, of at least 65, in particular of at least 67, preferably of at least 68. Since particularly favorable support effects occur in the region of the radially outer tread layer, due to the geometry of the sipe-channel combination, namely the radially outer sipe region of the sipe-channel combination, an optimization of the radially outer tread layer with respect to the rolling resistance is ensured in an at least substantially conflict-of-goal-free manner.According to a further preferred embodiment, the material boundary between the tread layers runs parallel to the tread periphery.According to a further preferred embodiment, the material boundary is at a distance from the level of the maximum depth of the incision-channel combination in the radial direction which is 10% to 80%, in particular 20% to 70%, preferably 30% to 50%, of the length of extent of the radially inner channel region determined in the radial direction. The tread therefore has the particularly cut-resistant, radially outer tread layer to a corresponding depth.It is furthermore preferred if the location of the incision-channel combination with the maximum width at the deepest location of the incision-channel combination, i.e. at the level of the maximum depth, has a distance in the radial direction of 60% to 85%, in particular of at least 70%, of the length of extent of the radially inner channel region determined in the radial direction.A further preferred embodiment provides that the radially inner channel region has an extension length determined in the radial direction of 25% to 70%, in particular of 30% to 65%, preferably of up to 50%, of the maximum depth of the associated incision-channel combination, or that the extension length determined in the radial direction of the radially inner channel region is 25% to 70%, in particular of 30% to 65%, preferably of up to 50%, of the maximum depth of the associated incision-channel combination.It is furthermore advantageous if the radially inner channel region has an extension length determined in the radial direction of at most 120%, in particular of at most 115%, preferably of at most 110%, particularly preferably of at most 105%, of its maximum width, or if the extension length of the radially inner channel region determined in the radial direction is at most 120%, in particular of at most 115%, preferably of at most 110%, particularly preferably of at most 105%, of its maximum width.A further advantageous embodiment provides that the radially outer sipe region, viewed in cross section, is composed in the radial direction of a first portion, which starts from the tread periphery and widens in a V-shape to this tread periphery, and of a second portion with the minimum width, which second portion narrows in the manner of an sipe, wherein the first portion has a maximum width at its radially outer end and an extension length in the radial direction of from 25% to 50%, in particular from 30% to 45%, of the extension length of the sipe region, wherein the first portion is bounded by two flanks which extend in a straight line and to the radial direction in each case at an angle of from 20° to 60°, in particular from 30° to 50°, and wherein the minimum width, the extension lengths and the angle are matched to one another particularly preferably in such a way that the maximum width is from 250% to 750%, in particular from 270% to 650%, preferably from 300% to 500%, the minimum width is.It is furthermore favorable if the radially outer tread layer is manufactured from a rubber mixture which contains fillers from the group carbon black(s), silica(s) and zinc oxide, wherein at least 60%, in particular at least 65%, preferably at least 75%, particularly preferably 85% to 90%, of the total amount of filler from the group silica(s) is or are.The invention further relates to a method for producing a vehicle tire, in particular a commercial vehicle tire, having a tread with at least one sipe-channel combination which has a maximum depth of 70% to 100% of the tread depth in the radial direction and is composed, as viewed in cross section, of a radially inner channel region and a radially outer sipe region having a minimum width of 0.4 mm to 3.0 mm determined parallel to the tread periphery, wherein the radially inner channel region has a greater cross-sectional area than the radially outer sipe region and a maximum width of 150% to 650% of the minimum width determined parallel to the tread periphery, wherein the tread has a radially inner tread layer made of a first rubber material and a radially outer tread layer, adjoining the latter, made of a second rubber material different from the first rubber material, wherein the radially inner channel region is embedded in the radially inner and the radially outer tread layer and a material boundary adjoining the radially inner channel region and interrupted by the latter is present between the tread layers, wherein the method comprises the following successive steps: a) extruding a green tread with at least two rubber mixture webs arranged one above the other in the radial direction to form the radially inner and the radially outer tread layer of the tread,▪ wherein the extruded green strip is provided with grooves extending into the two rubber compound sheets, and / or▪ grooves being introduced, in particular cut or pressed, into the extruded green strip, the grooves reaching into the two rubber mixture webs,b) Construction of a green tyre with the green tread strip and c) vulcanization of the green tyre in a vulcanization mould with mould segments for forming the tread, wherein the mould segments have profile webs for forming the incision-channel combinations of the tread profile and wherein, when the green tyre is formed in the vulcanization mould, profile webs retract into the grooves of the green tread strip.The method permits particularly precise production of the vehicle tire with the tread in the desired two-layer configuration, in particular also in the region of the grooves.Further features, advantages and details of the invention will now be described in more detail with reference to the drawing, which schematically shows an exemplary embodiment of the invention. Figure shows FIG. 1 shows a simplified plan view of a section of a tread of a utility vehicle tire in the region of a circumferential groove, and FIG. 2 is a sectional view taken along the line II--II of FIG. 1.Vehicle tires designed according to the invention are tires for multi-lane motor vehicles, the vehicle tires being in particular commercial vehicle tires, particularly preferably for trucks or buses. The commercial vehicle tires are furthermore preferably pneumatic vehicle tires, in particular of the radial type, and in particular for rims having a rim diameter of 17.5, 19.5 or 22.5 inches.The invention relates to a vehicle tire having a tread with at least one geometrically specially designed sipe-channel combination in conjunction with at least one tread layer having one or more special rubber properties. The geometry of an incision-channel combination and subsequently the rubber properties of the tread layers will be discussed first. Finally, results of tire tests are also presented.1. Description of Incision-Channel CombinationFIG. 1 shows a plan view of a section of a tread 1 of a commercial vehicle tire in the region of a specially designed circumferential groove 2 which extends in a straight manner in the circumferential direction and is an example of an incision-channel combination and separates two profile ribs 3 which are merely indicated in FIG. 1 from one another.The circumferential groove 2 is designed in the radial direction to the respectively provided profile depth T UR( FIG. 2 ), which for the preferred type of tire (commercial vehicle tire) is usually 9.0 mm to 26.0 mm. According to FIG. 2, the circumferential groove 2 is set (compare in plan view as viewed in the axial direction. Position of the line II-II in FIG. 1 ) together consists of a radially outer incision region 4 and a radially inner channel region 5.The following explanations regarding the circumferential groove 2, i.e. the radially outer incision region 4 and the radially inner channel region 5, relate to the mentioned cross section.The circumferential groove 2 is formed symmetrically with respect to a radial direction line L. Consequently, the cut portion 4 and the channel portion 5 are each formed symmetrically with respect to the line L.The incision region 4 has, with respect to the line L, in the radial direction an extension length c 1 of 30% to 75% of the profile depth T UR and in the axial direction a minimum width b min( width at the narrowest point) of 0.4 mm to 3.0 mm, in particular of 0.5 mm to 2.5 mm, preferably of 1.0 mm to 2.0 mm. In the exemplary embodiment shown, the incision region 4 is composed in the radial direction of a chamfer-like widened portion 4 a, which originates from the tread periphery, and of an incision-like narrowed portion 4 b, which opens into the channel region 5.The widened portion 4a has the shape of an isosceles trapezoid, widens in a V shape in the direction of the tread periphery, has a maximum width b a( width at the widest point in the axial direction at its radially outer end, i.e. at the tread periphery), and has the minimum width b min in the axial direction at its radially inner end, i.e. at the connection to the narrowed portion 4b, and-referred to the line L-an extension length c 1a of 25% to 50%, in particular of 30% to 45%, of the extension length c 1 of the incision region 4. The section 4 ais bounded by two flanks 6, which extend straight and also to the radial direction at an angle α of 20° to 60°, in particular 30° to 50°, respectively. The minimum width b min, the extension lengths c 1, c 1a and the angle α are preferably matched to one another such that the maximum width b is a250% to 750%, in particular 270% to 650%, preferably 300% to 500%, of the minimum width b min.The narrowed section 4b extends straight and in the radial direction, is bounded by two flanks 7 extending in the radial direction, has the mentioned minimum width b min in the axial direction and, with respect to the line L, an extension length c 1b in the radial direction, the size of which extension lengths c 1, c 1a follow.The radially inner channel region 5 has a larger cross-sectional area than the radially outer incision region 4, is composed of a radially outer channel portion 5 aand a radially inner channel portion 5 b, has a maximum width b max( width at the widest point) of 150% to 650%, in particular of 200% to 600%, preferably of 300% to 500%, particularly preferably of 350% to 450%, of the minimum width b min at the mutual connection of the channel portions 5 a, 5 bin the axial direction, and has an extension length c 2 of 25% to 70%, in particular of 30% to 65%, preferably of up to 50%, of the profile depth T UR in the radial direction, based on the line L. Preferably, the extension length c 2 and the maximum width b max are matched to one another such that the extension length c 2 is at most 120%, in particular at most 115%, preferably at most 110%, particularly preferably at most 105%, of the maximum width b max.The channel region 5 is bounded by a channel base 8 which extends at the profile depth T UR and simultaneously forms the groove base of the circumferential groove 2 and has a width b G determined in the axial direction of 2.0 mm to 5.0 mm, in particular of at least 3.0 mm, and by channel walls 9 which extend in the overall direction in an inverted and tilted manner into one profile rib 3 or into the other profile rib 3.The channel walls 9 each extend between the channel base 8 and the respective flank 7 in the narrowed section 4 b, each have a straight, radially outer ceiling flank 9 alocated in the radially outer channel section 5 aand a straight, radially inner side flank 9 blocated in the radially inner channel section 5 b. In the exemplary embodiment, the channel walls 9 furthermore each have three transition fillets 9 c, of which one runs between the channel base 8 and the radially inner side flank 9 b, another runs between the radially inner side flank 9 band the ceiling flank 9 aand yet another runs between the ceiling flank 9 aand the respective flank 7' in the narrowed section 4 b. The transition fillets 9 csecure tangential transitions and in particular each run along a radius of preferably 1.0 mm to 2.0 mm.The widest point with the maximum width b max is at a distance a 1 of 60% to 85%, in particular of at least 70%, of the extension length c 2 from the deepest point of the circumferential groove 1, i.e. from the channel base 8.The ceiling flanks 9 arun each at an angle β with respect to the radial direction, wherein a mutual distance determined in the axial direction between the ceiling flanks 9 increases continuously in the direction of the channel base 8 and therefore in the direction of the location of the maximum width b max. The radially outer channel section 5 atherefore widens continuously from the incision region 4 in the direction of the channel base 8 as far as the location of the maximum width b max. The side flanks 9 brun towards the radial direction at an angle γ of 10° to 25°, in particular 15° to 23°, preferably at least 17°, wherein a mutual distance determined in the axial direction between the side flanks 9 bis continuously reduced in the direction of the channel base 8. The radially inner channel section 5 btherefore narrows continuously in the direction of the channel base 8 starting from the location of the maximum width b max The distance a 1, the maximum width b max and the extension length c 2 are preferably matched to one another such that the angle β is 50° to 70°, in particular 55° to 60°.According to FIG. 2, the tread 1 (FIG. 1 ) and thus each profile rib 3 in the radial direction is composed of a radially inner tread layer 1 aand a radially outer tread layer 1 b, wherein the tread layers 1 a, 1 bare each made of a rubber material (vulcanisate of a rubber mixture) and wherein-as will be explained in more detail-the rubber material of the radially inner tread layer 1 adiffers from the rubber material of the radially outer tread layer 1 b, so that a material boundary 1 cis present between the tread layers 1 a, 1 b. The material boundary 1 c, as viewed in the cross section oriented in the axial direction, has a distance a 2 from the radially inner end of the radially inner channel section 5 b, i.e. from the level of the profile depth T UR or from the channel base 8, in the radial direction, which is 10% to 80%, in particular 20% to 70%, preferably 30% to 50%, of the extension length c 2 of the channel region 5, so that the material boundary 1 cis locally interrupted by the radially inner channel region 5. The channel base 8 is thus formed by the rubber material of the radially inner tread layer 1 a.2. Further description of tread layers 1a, 1b2.1 To the radially inner tread layer 1aThe rubber material of the radially inner tread layer 1 ais optimized with regard to its cut resistance to foreign bodies, for example, scotters, and has a specific "CSRI".The CSRI (compound stone trapping retention index) serves as an indicator of the cut resistance of the rubber material to foreign bodies and of the stone repellency of the rubber material. These properties (cut resistance, stone repellency) are considered via the CSRI in relation to an internal reference rubber material, as will be explained in more detail below.The higher the CSRI, the "softer" the rubber material. A rubber material with a higher CSRI releases (jammed) stones caught on the tread more easily by the centrifugal forces occurring during driving (good stone-repelling effect) compared to a rubber material with a lower CSRI, but is less favorable in terms of cut resistance.The smaller the CSRI, the "stiffer" the rubber material. A rubber material having a smaller CSRI is improved in cut resistance as compared with a rubber material having a larger CSRI.Due to the special geometric design of the circumferential groove 1, an optimization of the rubber material of the radially inner tread layer 1 ais not predominant with regard to its stone-repellent effect (CSRI as high as possible), because the radially outer incision region 4 ensures a good stone-repellent effect, so that the risk of stones penetrating into the region of the radially inner tread layer 1 ais low.The rubber material of the radially inner tread layer 1a has a "small" CSRI and is thus optimized with respect to the cut resistance. In particular after abrasion of the tread to the level of the radially inner channel region 5 (abrasion of the complete incision region 4), the channel region 5 is gradually opened or exposed clearly to the tread periphery, so that a high cut resistance of the rubber material of the radially inner tread layer 1 ais particularly favorable.The CSRI is obtained according to the following equation.The formula signs given in the equation are as follows:G' (100%) [kPa] Dynamic storage modulus at 100% elongation in kiloPascals:- Determination according to ASTM D6601-19:◯ Standard Test Method for Rubber Properties-Measurement of Curve and After-Curve Dynamic Properties Using a Rotorless Shear Rheometer◯ Last Update 15.05.2019◯ Vulcanization Parameters (Preparation of Test Specimens):▪ vulcanization temperature 170° C▪ Vulcanization Time 10 minutes- Measurement parameters:◯ 2.Deformation Sweep (2.Deformation Sweep)◯ Deformation Sequence 1Hz◯ temperature 70°Cσ (300%) [MPa] Stress value at 300% elongation in megapascals:- Determination according to DIN 53504 (DIN 53504:2017-03): Testing of rubber and elastomers - Determination of tear strength, tensile strength, elongation at break and tensile values in the tensile test◯ Edition 2017-03◯ Vulcanization Parameters (Preparation of Test Specimens):▪ vulcanization temperature 140° C▪ Vulcanization Time 30 minutesMeasurement parameters: as stated in the standard.The 693 kPa and 12.3 MPa values in Equation I are the values of the aforementioned reference internal rubber material (compare. Tables 1 and 2 below) above which consist primarily of conventional radially outer tread layers. This reference rubber material has a storage dynamic modulus at 100% elongation (G' (100%)) of 693 kPa and a stress value at 300% elongation (σ (300%)) of 12.3 MPa. The CSRI of the reference rubber material was thus set to 100 (compare. Table 2 below). Division by 2 (see equation above) provides a "mean" between the dynamic storage modulus at 100% strain (G' (100%)) and the stress value at 300% strain (σ (300%)). As is known, the respective magnitude of the dynamic storage modulus at 100% strain (G' (100%)) correlates with the magnitude of the stress value at 300% strain (σ (300%)), wherein a larger dynamic storage modulus at 100% strain is associated with a larger stress value at 300% strain.The rubber material of the radially inner tread layer 1a has a CSRI of up to 110, in particular up to 100, preferably up to 90.The rubber material of the radially inner tread layer 1 afurther has a stress value at 300% elongation (σ (300%)), which is in particular at least 10.5 MPa, preferably at least 11.0 MPa, particularly preferably at least 12.0 MPa, most preferably at least 12.5 MPa.The rubber material of the radially inner tread layer 1a also has a dynamic storage modulus at 100% elongation (G' (100%)), which is in particular at least 640 kPa, preferably at least 660 kPa, particularly preferably at least 700 kPa, and most preferably at least 750 kPa.Table 1 shows recipes, i.e. compositions of rubber mixtures, wherein the rubber mixture R belonging to the mentioned internal reference rubber material, a comparative rubber mixture V 1, which is a rubber mixture customary for radially inner tread layers, in particular for a so-called tread base, and three rubber mixtures E 1 a, E 1 b, E 1 c, which are examples according to the invention, are specified. Table 1: Recipes (composition of the rubber mixtures, tread layer 1a) Table 1: Recipes (composition of the rubber mixtures, tread layer 1a)Natural Rubber8510090100100Butadiene rubber15-10--Carbon black(s) (e.g., N121, N220, N339)4334433340Silica(s) & Silanes (e.g., TESPD; TESPT)4,55,07,55,016,0Processing Aid (Plasticizers, among others)3,0-1,0--Antiaging agent (6ppD, DTPD, TMQ, anti-ozonant wax)5,754,166,003,004,16Vulcanization chemicals (zinc oxide, stearic acid, accelerator, sulfur)7,58,57,38,78,5Total total163,8151,7164,8149,7168,7Table 2 shows the stress values at 300% elongation (σ (300%)), the dynamic storage modulus at 100% elongation (G' (100%)) and the CSRI, calculated according to equation I, of the rubber materials which are manufactured from the rubber mixtures R, V1, E1a, E1b, E1c given in table 1. Table 2: Properties of the rubber materials (tread layer 1a) Table 2: Properties of the rubber materials (tread layer 1a)σ (300%) [MPa]12,39,910,912,114,9G' (100%) [kPa]693633663777799CSRI1001171099585The rubber material from the comparative mixture V1 has a CSRI of 117. The rubber materials from the rubber mixtures E1a, E1b and E1c have-in comparison with the rubber material from the comparative mixture V1-a lower CSRI, namely a CSRI of 109 (E1a), 95 (E1b) and 85 (E1c), respectively, and are therefore significantly improved with respect to the cutting resistance compared with the rubber material from the comparative mixture V1. A radially inner tread layer 1 a, which consists of the rubber material of the rubber mixture E 1 a, E 1 band E 1 c, therefore makes it possible to expect very good cut resistance to foreign bodies.2.2 To the radially outer tread layer 1bThe rubber material of the radially outer tread layer 1b is optimized - in particular while maintaining good wet brake performance and low rolling resistance - with respect to chip / chunk resistance, which reflects the resistance of the rubber material to exfoliation under slip stress.The rebound resilience at a temperature of 23° C. (R (23° C.)) is used as indicator for the wet brake performance, the lower the rebound resilience R (23° C.), the better the wet brake performance to be expected. The rebound resilience R (23° C.) is a measure of the damping, the damping being higher the lower the rebound resilience. With lower rebound elasticity (higher damping) of the rubber material coming into contact with the substrate during rolling of the tire, more energy is "dissipated", whereby the wet braking performance of the tire is improved.The rebound resilience at a temperature of 70° C. (R (70° C.)) is used as an indicator of the rolling resistance, the greater the rebound resilience R (70° C.), the better (lower) the rolling resistance to be expected. For a low rolling resistance, a low "energy destruction" is required during the rolling of the tire in a known manner.The theoretical background on the above indicators results from the different frequency effects on the rubber material in the case of a vehicle tire braking on wet (water) and a vehicle tire rolling free (compare. Williams-Landel-Ferry Transformation, Frequency-Temperature Superposition, Temperature Dependence of Relaxation Mechanisms).Rebound elasticities R (23°C) and R (70°C) were determined as follows:- Determination according to ISO 4662: elastomers or thermoplastic elastomers - determination of the rebound resilience of vulcanisates◯ Counterpart Method (Pendulum Test) according to Section 5, Thickness of the test specimen 6.3 mm±0.5 mm (see Annex A - Use of non-standard test pieces)◯ Edition 2017-06◯ Vulcanization Parameters (Preparation of Test Specimens):▪ vulcanization temperature 140° C▪ Vulcanization Time 30 minutesMeasurement parameters: as stated in the standard and at a temperature (test specimen temperature) of 23° C. (for R (23° C.)) or of 70° C. (for R (70° C.)).The elongation at break ε R is used as an indicator for the chip / chunk resistance, the higher the elongation at break ε R the better the chip / chunk resistance to be expected.The elongation at break ε R is determined in accordance with DIN 53504 (DIN 53504:2017-03) (for details of the determination see above).The rubber material of the radially outer tread layer 1 bhas a rebound resilience R (23° C.) of up to 60, in particular of up to 57, preferably of up to 55.The rubber material of the radially outer tread layer 1 bhas, furthermore, a rebound resilience R (70° C.) of at least 65, in particular of at least 67, preferably of at least 68.The rubber material of the radially outer tread layer 1 bhas, in addition, an elongation at break ε R of at least 430%, in particular of at least 440%, preferably of at least 450%, particularly preferably of at least 460%, most preferably of at least 470%.The radially outer tread layer 1 bis manufactured from a rubber mixture which contains as fillers exclusively carbon black(s), silica(s) (silica) and zinc oxide(s), wherein at least 60% (mass %), in particular at least 65%, preferably at least 75%, particularly preferably 85% to 90%, of the total amount of fillers present is or are silica(s). The amount of silica(s) contained in the radially outer tread layer 1 b, i.e. in the rubber material, can be determined by burning a rubber material sample and subsequent analysis of the ash remaining.Table 3 shows recipes, i.e. compositions of rubber mixtures, wherein three comparative rubber mixtures V2a, V2b, V2c and one rubber mixture E2 designed according to the invention are specified or is indicated. Table 3: Recipes (composition of the rubber mixtures, tread layer 1b) Table 3: Recipes (composition of the rubber mixtures, tread layer 1b)Natural Rubber751008080Butadiene rubber25---SSBR 21S65V--10-SSBR 15S25V--1020Carbon black (N220)51,3322,545Conventional silica (e.g., Evonik VN3)1013,5--HD Silica (Solvay Z1165 MP)-5560Disilanes (TESPD)-1--Tetra-silane (TESPT)1,334,87Blocked mercaptosilane (NXT silane from Momentive) & silane-functionalized butadiene oligomer (POLYVEST ST-E 60 from Evonik)---12,5Processing Aid (Plasticizers, among others)325<row><cell>Antiaging agent (6ppD, DTPD, TMQ, anti-ozonant wax)< / cell><cell>5,5< / cell><cell>3,75< / cell><cell>3,6< / cell><cell>4,5< / cell>< / row><row><cell>Zinc oxide< / cell><cell>3< / cell><cell>4< / cell><cell>1< / cell><cell>3< / cell>< / row><row><cell>Other vulcanization chemicals (stearic acid, thiuram accelerator (CBS or TBBS), sulfur donor (TBzTD), DPG, sulfur, CTP)< / cell><cell>4,7< / cell><cell>7,6< / cell><cell>5,77< / cell><cell>6,05< / cell>< / row><row><cell>Total total< / cell><cell>178,9< / cell><cell>152,4< / cell><cell>176,2< / cell><cell>196,1< / cell>< / row><p xml:id="_7e62d70372" n="0070">The rubber mixture E2 thus contains 60 phr of silica (silica), 5 phr of carbon black and 3 phr of zinc oxide as fillers. The total amount of fillers is therefore 68 phr. The (mass) proportion of silica, based on the total amount of fillers, is therefore about 88% (=(60 / 68)*100).<p xml:id="_7e62d70373" n="0071">Table 4 shows the above-mentioned properties of the rubber materials made of the rubber compositions shown in Table 3. Table 4: Properties of the rubber materials (tread layer 1b)<title desc="title">Table 4: Properties of the rubber materials (tread layer 1b)R (23°C) [-]54,768,751,252,9R (70°C) [-]65,375,964,968,2ε R [%]421379466473The rubber material from the rubber mixture E 2 has-in comparison with the rubber materials from the rubber mixtures V 2 a, V 2 b, V 2 c-the greatest elongation at break ε R, namely an elongation at break of 473%, wherein the elongation at break is significantly greater than in the case of the rubber material from the rubber mixtures V 2 a, V 2 band is slightly or insignificantly greater than that from the rubber material V 2 c. A radially outer tread layer 1 bconsisting of the rubber material of the rubber mixture E 2 therefore allows very good chip / chunk resistance to be expected.The rubber material from the rubber mixture E2 also has-in comparison with the rubber materials from the rubber mixtures V2a, V2b, V2c-the second smallest rebound resilience R (23°C), namely a rebound resilience R (23°C) of 52.9. A radially outer tread layer 1 bconsisting of the rubber material of the rubber mixture E 2 therefore continues to expect good wet braking performance.The rubber material from the rubber mixture E2 moreover has-in comparison with the rubber materials from the rubber mixtures V2a, V2b, V2c-the second greatest rebound resilience R (70°C), namely a rebound resilience R (70°C) of 68.2. A radially outer tread layer 1 bconsisting of the rubber material of the rubber mixture E 2 therefore continues to be expected to have a good (low) rolling resistance.The rubber material of the radially outer tread layer 1 bis thus optimized with regard to chip / chunk resistance, while maintaining good wet brake performance and low rolling resistance, as already mentioned.3. Tire TestsTRUCK tires of dimension 205 / 75 R 17.5 (tire designation CHS3 124L) were produced with a two-layer tread 1, the radially inner tread layer 1a each being produced from the rubber compound E1c and the radially outer tread layer 1b from the rubber compounds V2a, V2b, V2c or E2. The wet brake performance, the rolling resistance and the chip / chunk resistance of the tires, i.e. in each case of the radially outer tread layer 1 b, were tested. The test conditions are given below.Test for wet brake performance: <row><cell>- Air temperature:< / cell><cell>17° C. to 21° C< / cell>< / row><row><cell>- Roadway temperature:< / cell><cell>17° C. to 21° C< / cell>< / row><row><cell>- ABS:< / cell><cell>Yes< / cell>< / row><row><cell>- Speed:< / cell><cell>80 km / h< / cell>< / row><p xml:id="_7e62d70430" n="0078">Test for rolling resistance:<list xml:id="_7e62d70431" type="bulleted"><item>- Determination according to ISO 28580<list xml:id="_7e62d70433" type="bulleted"><item> Passenger Car, Truck and Bus Tire Rolling Resistance Measurement Method - One-point Check and Correlation of Measurement Results< / item>< / list>< / item>< / list><p xml:id="_7e62d70435" n="0079">Test for chip / chunk resistance:<title desc="title" / ><row><cell>- Axis position:< / cell><cell>Drive Axle< / cell>< / row><row><cell>- Route:< / cell><cell>964 km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km km< / cell>< / row><row><cell>- Link State:< / cell><cell>Poor Path Section (Ballast)< / cell>< / row><row><cell>- Air temperature:< / cell><cell>10° C. to 15° C< / cell>< / row><row><cell>- Judgment:< / cell><cell>Relative Comparison of Damage to Tread by Visual Inspection< / cell>< / row><p xml:id="_7e62d70458" n="0080">Table 5 contains the results of the tire tests, wherein the values for the tire having the radially outer tread layer 1 bof the rubber mixture V 2 aare each set to 100. Values less than 100 indicate a deterioration of the respective tire property compared with the tire having the tread whose radially outer tread layer 1 bhas been produced from the rubber mixture V 2 a. Values greater than 100 indicate an improvement in the respective tire property over the tire mentioned. Table 5: Results of Tire Tests<title desc="title">Table 5: Results of Tire TestsRolling resistance is rolling resistance100120103102Wet Braking Performance10087119120Chip / Chunk Resistance100597116Chip / Chunk ResistanceAccording to Table 5, the tires with a tread with the radially outer tread layer produced from the rubber mixture E2 exhibited a significantly better chip / chunk resistance (116) than the tires with a tread with a radially outer tread layer produced from one of the rubber mixtures V2a (100), V2b (5), V2c (95). The chip / chunk resistance of the tire with a tread with a radially outer tread layer made of the rubber compounds V2b was unacceptable.For Wet Braking PerformanceIn addition, the tires with a tread with the radially outer tread layer made of the rubber compound E2 exhibited the best wet brake performance (120) of all the tires, wherein the wet brake performance was significantly better than those tires whose tread had a radially outer tread layer made of the rubber compound V2a or V2b, respectively, and wherein the wet brake performance was substantially comparable to those tires whose tread had the radially outer tread layer made of the rubber compound V2c (119).For rolling resistanceThe rolling resistance (102) of the tires with the tread with the radially outer tread layer manufactured from the rubber mixture E2 was comparable to the rolling resistance of the tires with the tread with the radially outer tread layer manufactured from the rubber mixture V2a or V2c. Although the rolling resistance of the tires with the tread with the radially outer tread layer manufactured from the rubber compound V2b was better (lower) than the rolling resistance of the tires with the radially outer tread layer manufactured from the rubber compound E2, the chip / chunk resistance (5) of the first-mentioned tire is unacceptable-as already mentioned above.The test results therefore show that chip / chunk resistance is improved by a radially outer tread layer 1 bmade of the rubber material of the rubber mixture E 2-while maintaining good wet brake performance and low rolling resistance. The wet brake performance is even improved as well.4. Method for producing a vehicle tyre, in particular a commercial vehicle tyreA method for producing a vehicle tire embodied according to the invention comprises the following steps: a) extruding a green tread with at least two rubber compound webs arranged one above the other in the radial direction to form the tread layers,◯ wherein the extruded green strip is provided with grooves which extend into two rubber compound webs, and / or◯ grooves being introduced, in particular cut or pressed, into the extruded green strip, the grooves reaching into the two rubber mixture webs,b) Construction of a green tyre with the green tread strip and c) vulcanization of the green tyre in a vulcanization mould with mould segments for forming the tread, wherein the mould segments have profile webs for forming the grooves of the tread profile and wherein, when the green tyre is formed in the vulcanization mould, profile webs enter the grooves of the green tread strip.5. Further Exemplary EmbodimentsThe invention is not limited to the described exemplary embodiment.As already mentioned, the circumferential groove explained in the embodiment is an example of a combination of cut-and-channel. The incision-channel combination can also be, for example, a correspondingly designed transverse groove which, when viewed in plan view, runs at an angle of, in particular, 0° to 50° with respect to the axial direction and runs at an angle of, in particular, 0° to 50°.The incision-channel combination has a maximum depth (depth at the deepest point) of 70% to 100%, in particular of at least 80%, of the profile depth (depth of the respectively deepest groove(s)) in the radial direction.The radially outer incision region 4 can be designed without a widened section 4 a, so that the radially outer incision region 4 is formed exclusively by the incision-like narrowed section 4 b. In this embodiment, the narrowed portion 4 bthus extends as far as the tread periphery.The tread 1 can have, in relation to the radial direction, in addition to the tread layers 1 a, 1 b, one or more further tread layers. The radially inner channel region 5 is embedded in each case in the radially inner and the radially outer tread layer 1 a, 1 b. The radially outer tread layer 1 btherefore reaches at least as far as the radially outer end of the radially inner channel region 5 and the radially inner tread layer 1 acircumulates the deepest point of the radially inner channel region 5. the radially outer tread layer 1 bhas a distance of at most 3.0 mm from the tread periphery in the radial direction.The radially outer tread layer 1 bmay consist of a rubber material which differs from the rubber material described in the context of the exemplary embodiment.List of reference characters1 Tread 1a Radially inner tread layer 1b Radially outer tread layer 1c Material boundary 2 Circumferential line 3 Profile rib 4 Radially outer incision region 4a Widened section 4b Narrowed section 5 Radially inner channel region 5a Radially outer channel section 5b Radially inner channel section 6 Flank 7 Flank 8 Channel base 9 Channel wall 9a Ceiling flank 9b Lateral flank 9c Transition rounded portion a 1, a 2 Distance b a Maximum width b G Width b max Maximum width b min Minimum width c 1, c 1a, c 1b, c 2 extension length L line T UR profile depth α, β, γ angleReferences included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedEP 3 984 775 A1

[0002] JP 432 796 2 B2

[0003] WO 2018 / 118023 A1

[0004] WO 2017 / 105496 A1

[0005] US 2021 / 0155046 A1

[0006] Cited Non-Patent LiteratureDIN 53504 (DIN 53504:2017-03 [0010, 0050, 0064]

Claims

Vehicle tyre, in particular commercial vehicle tyre, having a tread (1) with at least one sipe-channel combination (2) which originates from the tread periphery and which has a maximum depth (T UR) of 70% to 100% of the tread depth (T UR) in the radial direction and, as viewed in cross section, is composed of a radially inner channel region (5) and a radially outer sipe region (4) having a minimum width (b min) of 0.4 mm to 3.0 mm, which minimum width is determined parallel to the tread periphery, wherein the radially inner channel region (5) has a larger cross-sectional area than the radially outer sipe region (4) and a maximum width (b max) of 150% to 650% of the minimum width (b min) which maximum width is determined parallel to the tread periphery, wherein the tread (1) has a radially inner tread layer (1a) made of a first rubber material and a radially outer tread layer (1b) adjoining the latter made of a second rubber material different from the first rubber material, characterized in that the radially inner channel region (5) is embedded in the radially inner and the radially outer tread layer (1a, 1b) and a material boundary (1c) adjoining the radially inner channel region (5) and interrupted by the latter is present between the tread layers (1a, 1b), wherein the first rubber material, which consists of the radially inner tread layer (1a), a CSRI of up to 110 determined according to the following equation: C S R I = 693 k P a ⋅ 100 G ' (100%) [k P a ]+12.3 M P a ⋅ 100 σ (300%) [M P a ] 2 CSRI compound stone trapping retention index G' (100%) [kPa] dynamic storage modulus at 100% elongation in kilopascals, determined according to ASTM D6601-19 σ (300%) [MPa] stress value at 300% elongation in megapascals, determined according to DIN 53504 (DIN 53504: 2017-03).Vehicle tyre according to Claim 1, characterized in that the second rubber material, from which the radially outer tread layer (1b) consists, has an elongation at break (ε R) according to DIN 53504 of at least 430%, in particular of at least 440%, preferably of at least 450%, particularly preferably of at least 460%, most preferably of at least 470%.Vehicle tyre according to Claim 1 or 2, characterized in that the CSRI of the first rubber material is up to 100, preferably up to 90.Vehicle tyre according to one of Claims 1 to 3, characterized in that the stress value at 300% elongation (σ (300%)) of the first rubber material of which the radially inner tread layer (1a) consists is at least 10.5 MPa, in particular at least 11.0 MPa, preferably at least 12.0 MPa, and particularly preferably 12.5 MPa.Vehicle tyre according to one of Claims 1 to 4, characterized in that the dynamic storage modulus at 100% elongation (G' (100%)) of the first rubber material of which the radially inner tread layer (1a) consists is at least 640 kPa, in particular at least 660 kPa, preferably at least 700 kPa, and particularly preferably at least 750 kPa.Vehicle tyre according to one of Claims 1 to 5, characterized in that the second rubber material, from which the radially outer tread ply (1b) consists, has a rebound resilience at a temperature of 23°C (R (23°C)), determined according to ISO 4662, of up to 60, in particular of up to 57, preferably of up to 55.Vehicle tyre according to one of Claims 1 to 6, characterized in that the second rubber material, from which the radially outer tread layer (1b) consists, has a rebound resilience at a temperature of 70°C (R (70°C)), determined according to ISO 4662, of at least 65, in particular of at least 67, preferably of at least 68.Vehicle tyre according to one of Claims 1 to 7, characterized in that the material boundary (1c) between the tread layers (1a, 1b) runs parallel to the tread periphery.Vehicle tyre according to one of Claims 1 to 8, characterized in that the material boundary (1c) has a distance (a 2) from the level of the maximum depth (T UR) of the sipe-channel combination (2) in the radial direction, which distance is 10% to 80%, in particular 20% to 70%, preferably 30% to 50%, of the extent length (c 2) of the radially inner channel region (5) determined in the radial direction.Vehicle tyre according to one of Claims 1 to 9, characterized in that the location of the sipe-channel combination (2) having the maximum width (b max) to the deepest location of the sipe-channel combination (2), that is to say to the level of the maximum depth (T UR), has a distance (a 1) of 60% to 85%, in particular of at least 70%, in the radial direction of the extent length (c 2) of the radially inner channel region (5) determined in the radial direction.Vehicle tyre according to one of Claims 1 to 10, characterized in that the radially inner channel region (5) has an extension length (c 2) determined in the radial direction of from 25% to 70%, in particular from 30% to 65%, preferably up to 50%, of the maximum depth (T UR) of the associated sipe-channel combination (2), or in that the extension length (c 2) of the radially inner channel region (5) determined in the radial direction is from 25% to 70%, in particular from 30% to 65%, preferably up to 50%, of the maximum depth (T UR) of the associated sipe-channel combination (2).Vehicle tyre according to one of Claims 1 to 11, characterized in that the radially inner channel region (5) has an extension length (c 2) determined in the radial direction of at most 120%, in particular of at most 115%, preferably of at most 110%, particularly preferably of at most 105%, of its maximum width (b max) or in that the extension length (c 2) of the radially inner channel region (5) determined in the radial direction is at most 120%, in particular of at most 115%, preferably of at most 110%, particularly preferably of at most 105%, of its maximum width (b max).Vehicle tyre according to one of Claims 1 to 12, characterized in that the radially outer sipe region (4) is composed, as viewed in cross section, in the radial direction of a first portion (4a) which originates from the tread periphery and widens in a V shape towards the latter, and of a second portion (4b) which narrows in an sipe-like manner and has the minimum width (b min) wherein the first portion (4) has, at its radially outer end, a maximum width (b a) and, in the radial direction, an extension length (c 1a) of from 25% to 50%, in particular from 30% to 45%, of the extension length (c 1) of the sipe region (4), wherein the first portion (4a) is bounded by two flanks (6), which run straight and with respect to the radial direction in each case at an angle (α) of 20° to 60°, in particular of 30° to 50°, and wherein the minimum width (b min), the extension lengths (c 1, c 1a) and the angle (α) are particularly preferably matched to one another in such a way that the maximum width (b is a) 250% to 750%, in particular of 270% to 650%, preferably of 300% to 500%, of the minimum width (b min).Vehicle tyre according to one of Claims 1 to 13, characterized in that the radially outer tread layer (1b) is produced from a rubber mixture which comprises fillers from the group carbon black(s), silica(s) and zinc oxide, wherein at least 60%, in particular at least 65%, preferably at least 75%, particularly preferably 85% to 90%, of the total amount of filler from the group silica(s) is or are.Method for producing a vehicle tyre, in particular a commercial vehicle tyre, having a tread (1) with at least one sipe-channel combination (2) which has a maximum depth (T UR) of 70% to 100% of the profile depth (T UR) in the radial direction and, as viewed in cross section, is composed of a radially inner channel region (5) and a radially outer sipe region (4) having a minimum width (b min) of 0.4 mm to 3.0 mm, which width is determined parallel to the tread periphery, wherein the radially inner channel region (5) has a larger cross-sectional area than the radially outer sipe region (4) and a maximum width (b max) of 150% to 650% of the minimum width (b min) which width is determined parallel to the tread periphery, wherein the tread (1) has a radially inner tread layer (1a) made of a first rubber material and a radially outer tread layer (1b) adjoining the latter made of a second rubber material different from the first rubber material, wherein the radially inner channel region (5) is embedded in the radially inner and the radially outer tread layer (1a, 1b) and a material boundary (1c) adjoining the radially inner channel region (5) and interrupted by the latter is present between the tread layers (1a, 1b), wherein the method comprises the following steps which take place in succession: a) extruding a green tread with at least two rubber compound webs arranged one above the other in the radial direction to form the radially inner and the radially outer tread layer (1a, 1b) of the tread (1), ▪ wherein the extruded green tread is provided with grooves which reach into the two rubber compound webs, and / or ▪ wherein grooves are introduced, in particular cut or pressed, into the extruded green tread, wherein the grooves extend into the two rubber mixture webs, b) construction of a green tyre with the green tread and c) vulcanization of the green tyre in a vulcanization mould with mould segments for shaping the tread, wherein the mould segments have profile webs for shaping the cut-channel combinations of the tread profile and wherein, during the shaping of the green tyre in the vulcanization mould, profile webs enter the grooves of the green tread.

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