Rubber composition for tyres

Abstract

The present invention relates to a cross-linkable rubber composition, a cross-linked rubber composition obtained by cross-linking such a rubber composition, a method of preparing a tyre and a tyre. The cross-linkable rubber composition comprises, per hundred parts by weight of rubber (phr): 100 phr of a blend of polybutadiene rubber (BR) and solution polymerized styrene-butadiene rubber (SSBR), a filler, and a resin, wherein the composition comprises: ≥ 10 phr to ≤ 35 phr of a polybutadiene rubber and ≥ 65 phr to ≤ 90 phr of a solution polymerized styrene-butadiene rubber having a styrene content in a range of 35 % to 45 % and a vinyl content in a range of 10% to 30%, determined by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy according to ISO 21561-2:2016, ≥ 70 phr to ≤ 100 phr of a silica filler having a BET surface area in a range of ≥ 250 m2 / g to ≤ 300 m2 / g, and ≥ 15 phr to ≤ 50 phr of carbon black.

Description

[0001] Rubber composition for tyres

[0002] The present invention relates to a cross-linkable rubber composition, a cross-linked rubber composition obtained by cross-linking the rubber composition, a method of preparing a tyre and a tyre.

[0003] Tread rubber is one of the important portions of a pneumatic tyre which contributes enormously to the overall performance of a tyre. A tyre has to exhibit a variety of performances, particularly regarding savety requirements which is a basic prerequisite for a tyre. For savety, a short braking distance is preferred. The braking distance strongly depends on the grip performance of the tyre tread in dry and wet conditions.

[0004] The tyre industry has developed techniques to achieve required performances of a tyre by incorporating of different rubber components and other components including silica into the tyre tread that comes into contact with the road surface. Including silica, for example, is known to result in tyre treads with lower rolling resistance and improved wet traction performance, resulting in better safety. On the other hand, it is also common knowledge in the tyre industry that improvements in grip in dry and wet condition is very challenging to be achieved without major tradeoff in rolling resistance, and that improvements in rolling resistance often occur in tandem with a reduction in wet traction, and vice versa.

[0005] US 2017 / 0158844 Al discloses a rubber composition for a tread with a balanced property of fuel economy, wet grip performance, and abrasion resistance. The rubber compositions for a tyre tread described therein comprise a natural rubber, a polybutadiene rubber, a silica, a carbon black, and a hydrogenated terpene or alpha-methylstyrene resin.

[0006] US 2019 / 0062537 Al discloses a rubber composition comprising a polybutadiene rubber and solution polymerized styrene-butadiene rubbers, a silica and alpha-methylstyrene resin. However, for improving rolling resistance with minimum impact on wet and dry braking a rubber composition comprising a high vinyl polybutadiene, a styrene-butadiene rubber, a natural rubber, silica, and a terpene resin is described.

[0007] US 2020 / 254818 Al refers to a motorcycle tire having excellent overall performance including dry grip performance, wet braking performance, abrasion resistance, ice performance, and color tone. Disclosed are tread rubber compositions comprising styrene-butadiene rubber, silica, carbon black, and a resin. EP 4 282 913 Al refers to a rubber composition comprising from 50 phr to 100 phr of a styrene butadiene rubber; from 0 phr to 50 phr of at least one further diene based rubber; from 95 phr to 200 phr of a fdler comprising from 50 phr to 100 phr of silica, from 40 phr to 70 phr of carbon black, and from 5 phr to 30 phr of an inorganic metal hydroxide; and from 40 phr to 80 phr of a plasticizer comprising a hydrocarbon resin having a softening point within a range of from 80°C to 130°C.

[0008] The present invention has the object to provide a composition for a tyre tread that provides improved wet grip and dry grip performance without major tradeoff in rolling resistance.

[0009] This object is achieved by a cross-linkable rubber composition according to claim 1, a cross-linked rubber composition according to claim 10, a method according to claim 14 and a tyre according to claim 15. Advantageous embodiments are the subject of dependent claims. They may be combined freely unless the context clearly indicates otherwise.

[0010] Hence, a cross-linkable rubber composition is provided, the cross-linkable rubber composition comprising, per hundred parts by weight of rubber (phr):

[0011] 100 phr of a blend of polybutadiene rubber (BR) and solution polymerized styrenebutadiene rubber (SSBR), a filler, and a resin, wherein the composition comprises:

[0012] > 10 phr to < 35 phr of a polybutadiene rubber and

[0013] > 65 phr to < 90 phr of a solution polymerized styrene-butadiene rubber having a styrene content in a range of 35 % to 45 % and a vinyl content in a range of 10% to 30%, determined by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy according to ISO 21561-2:2016,

[0014] > 70 phr to < 100 phr of a silica filler having a BET surface area in a range of > 250 m2 / g to < 300 m2 / g, and

[0015] > 15 phr to < 50 phr of carbon black.

[0016] It has surprisingly been found that a rubber composition comprising a blend of polybutadiene rubber and a solution polymerized styrene-butadiene rubber having a high styrene content and low vinyl content in combination with silica having a high BET surface area and with a certain amount of carbon black provides for an improved braking performance on wet as well as on dry ground, without major tradeoff in rolling resistance. A combination of good braking performance on wet as well as on dry ground combined with good rolling resistance is difficult to balance and provides a notable advantage, particularly for summer tyres. As used herein, the term “wet grip” refers to how well a tyre grips the road and brakes when on a wet surface. The term “dry grip” refers to how well a tyre grips the road and brakes when on a dry surface. As used herein, the term “rolling resistance” refers to the force stopping a tyre when moving across a road or surface, generally referring to how easily a tyre rolls across a surface. As used herein, the term “handling” refers to how well a vehicle handles the road and how well the vehicle responds to steering input. Tyre handling is a measurement of what a driver can perform with a car such as steering, stability during lane change and cornering, lap time, accelerating and braking.

[0017] It will be understood that in formulations discussed in connection with the present invention the phr amount of all rubber components adds up to 100 phr. The cross-linkable rubber composition according to the invention comprises cross-linkable groups in the individual rubber components. They may be cross-linked (cured, vulcanised) by methods known to a skilled person in the rubber technology field.

[0018] In alternative embodiments, the silica filler has a BET surface area in a range of > 190 m2 / g to < 320 m2 / g, determined according to ASTM DI 993. The BET (Brunauer, Emmett and Teller) theory is commonly used to evaluate gas adsorption data and generate a specific surface area result expressed in units of area per mass of sample (m2 / g). The technique is referenced by several standard organizations such as ASTM. In alternative embodiments, the silica filler has a BET surface area in a range of > 190 m2 / g to < 220 m2 / g, preferably in a range of > 200 m2 / g to < 220 m2 / g, determined according to ASTM DI 993. In embodiments, the silica filler has a BET surface area in a range of > 250 m2 / g to < 300 m2 / g, preferably in a range of > 275 m2 / g to < 300 m2 / g, or in a range of > 300 m2 / g to < 320 m2 / g, determined according to ASTM D1993.

[0019] The rubber composition comprises a silica filler having a high BET surface area. Silica which meets a BET surface area of 190 to 320 m2 / g includes highly dispersible silica (HDS). Highly dispersible silica may be precipitated from a silicate solution, for example, by hydrolysis and / or high temperature oxidation conversion. Examples of commercial silica having a BET surface area of 190 to 220 m2 / g is Zeosil HRS 1200MP (BET: 200 m2 / g) manufactured by Solvay AG. An example of commercial silica having a BET surface area of 150-300 m2 / g is Zeosil Premium SW (BET: 275 m2 / g) manufactured by Solvay AG. Examples of commercial silica having a BET surface area of 300 m2 / g are Hi-Sil EZ200G available from PPG Industries or MFILL 300 available from Madhu Silica Pvt. Ltd.

[0020] In embodiments, the composition comprises the silica filler in a range of > 75 phr to < 90 phr. In embodiments, the composition comprises in a range of > 70 phr to < 100 phr, preferably in a range of > 75 phr to < 90 phr, of a silica filler having a BET surface area in a range of > 190 m2 / g to < 220 m2 / g, more preferably in a range of > 200 m2 / g to < 220 m2 / g, or in a range of > 250 m2 / g to < 300 m2 / g, preferably in a range of > 275 m2 / g to < 300 m2 / g or in a range of > 300 m2 / g to < 320 m2 / g, determined according to ASTM DI 993. It was found that such amounts of silica having a high BET surface area in combination with a carbon black and the rubber blend advantageous test results of the cured rubber regarding an improvement in braking performance on dry as well as on wet surface.

[0021] The rubber composition further comprises > 15 phr to < 50 phr of carbon black. Carbon black refers to a finely dispersed amorphous carbon material produced by combustion or thermal decomposition of gas and liquid hydrocarbons. In embodiments, the composition may comprise a super abrasion furnace (SAF) grade carbon black or a high-abrasion furnace (HAF) grade carbon black. Examples for commercial super abrasion furnace (SAF) grade carbon black are, for example, available under the trade name CORAX® N134, CORAX® N121 or CORAX® N220 ASTM grade Carbon Black manufactured by Orion Engineered Carbons, or CD2109 carbon black. Such carbon black has high surface area. An example for a commercial HAF-HS (High Abrasion Furnace-High Structure) grade carbon black is available, for example, as N339 Carbon Black manufactured by Columbian Chemicals Company.

[0022] In embodiments, the composition comprises carbon black, particularly SAF grade carbon black or HAF or HAF-HS grade carbon black, in a range of > 20 phr to < 30 phr. It was found that such higher amount of carbon black provides a positive effect with regard to wet grip of the cured rubber composition.

[0023] The ratio of the silica filler to the carbon black may be in a range of from 2: 1 to 5: 1. In embodiments, the composition comprises a silica filler in a range of > 75 phr to < 90 phr and carbon black in a range of > 20 phr < 30 phr. It is assumed that the combination of silica and carbon black, preferably high structure carbon black, can provide an advantage of improved dry braking and milage.

[0024] The composition comprises 100 phr of a blend of polybutadiene rubber (BR) and solution polymerized styrene -butadiene rubber (SSBR). It is assumed that the blend of BR and SSBR contributes to the improvements in grip and durability. The composition comprises > 10 phr to < 35 phr of a polybutadiene rubber and > 65 phr to < 90 phr of a solution polymerized styrene-butadiene rubber having a styrene content in a range of 35 % to 45 % and a vinyl content in a range of 10% to 30%, determined by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy according to ISO 21561-2:2016. It is understood that in the composition the phr amount of all rubber components adds up to 100 phr. It is further assumed that the improvement in grip and durability is based on the rubber blend consisting of BR and a specific SSBR, not including a further rubber, such as, for example, further SSBRs or a natural rubber. In embodiments, the solution polymerized styrene-butadiene rubber has a styrene content in a range of 35 % to 45 % and a vinyl content in a range of 20% to 30%, determined by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy according to ISO 21561-2:2016.

[0025] In embodiments, the composition comprises the SSBR in a range of > 75 phr to < 90 phr. In embodiments, the composition comprises in a range of > 65 phr to < 90 phr, preferably in a range of > 75 phr to < 90 phr, of the solution polymerized styrene-butadiene rubber having a styrene content in a range of 35 % to 45 % and a vinyl content in a range of 10% to 30%, preferably in a range of 20% to 30%, determined by attenuated total reflectance Fourier transform infrared (ATR- FTIR) spectroscopy according to ISO 21561-2:2016. A specific example for a commercial SSBR having a styrene content of 35-45 % and a vinyl content of 20-30% is Sprintan 918S manufactured by Synthos. Without being bound to a specific theory it is assumed that a polymer blend comprising BR and SSBR with such styrene and vinyl content contributes to an improved grip and durability of the cured composition that is particularly advantageous for summer tyres.

[0026] In embodiments, the composition comprises a polybutadiene rubber (BR) in a range of > 15 phr to < 25 phr. In embodiments, the butadiene rubber (BR) has a cis group content, as determined by infrared spectroscopy (IR), of > 95%, preferably of > 96%. A butadiene rubber (BR) with a high cis group content, is obtained under neodymium catalysis (Nd BR). The cis content of the polybutadiene rubber is usually provided by the supplier and may be determined with FTIR Fourier-transform infrared spectroscopy). The method is based on the calculation of the ratio between the intensity of the bands attributable to the 1,4-trans and 1,2-vinyl isomers and a reference band (internal standard) falling at 1312 cm'1(L. J. Bellamy, The Infrared Spectra of Complex Molecules, Vol. 1 Third Edition, Chapman and Hall). The 1,4-cA content is determined by the difference from 100. Butadiene rubber obtained under neodymium catalysis may be denoted a cis 1,4-polybutadine.

[0027] In embodiments, the composition comprises a resin selected from the group of alpha-methyl styrene (AMS) resin, terpene resin, polyterpene resin, terpene phenolic resin, a C5 resin, C9 resin, coumarone indene resin, dicyclopentadiene (DCPD) resin or a combination thereof. In embodiments, the composition comprises an alpha-methyl styrene resin. A variety of hydrocarbon resins may be used. The term “alpha-methyl styrene resin” refers to copolymer resins of styrene and alpha-methyl styrene. Examples of the polyterpene resins include terpene homopolymer or copolymer resins polymerised from terpene compounds such as a-pinene, -pinene, limonene, dipentene, or P-pinene / limonene, as well as hydrogenated terpene resins prepared by hydrogenating any of the terpene resins. The term “C5 resin” refers to hydrocarbon resins obtained from the polymerization of C5 aliphatic olefin and diolefin. The term “C9 resin” refers to aromatic hydrocarbon resins made from C9, or more generally from a C8 to CIO fraction, aromatic hydrocarbons. Important base monomers are indene, methyindenes, dicyclopentadiene, styrene, alpha-methylstyrene and various vinyl toluenes.

[0028] In embodiments, the composition comprises in a range of > 15 phr to < 30 phr, preferably in a range of > 20 phr to < 25 phr, of a resin selected from the group of alpha-methyl styrene resin, terpene resin, polyterpene resin, terpene phenolic resin, a C5 resin, C9 resin, coumarone indene resin, dicyclopentadiene (DCPD) resin or a combination thereof, preferably of alpha-methyl styrene resin. Such embodiments provide particularly improved wet grip.

[0029] In embodiment, the cross-linkable rubber composition comprises:

[0030] > 10 phr to < 35 phr, preferably > 15 phr to < 25 phr, of BR;

[0031] > 65 phr to < 90 phr, preferably > 75 phr to < 90 phr, of a SSBR, preferably having a styrene content in a range of 35 % to 45 % and a vinyl content in a range of 10 % to 30%, preferably of 20 % to 30%, determined by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy according to ISO 21561-2:2016;

[0032] > 70 phr to < 100 phr, preferably > 75 phr to < 90 phr, of the silica filler, having a BET surface area in a range of > 250 m2 / g to < 300 m2 / g (according to ASTM D1993);

[0033] > 15 phr to < 35 phr, preferably > 20 phr to < 30 phr, of carbon black, and a resin, optionally > 15 phr to < 35 phr, preferably > 20 phr to < 30 phr, of the resin, preferably alpha-methyl styrene resin.

[0034] Such rubber compositions comprising polybutadiene rubber and a solution polymerized styrenebutadiene rubber having a high styrene content and low vinyl content in combination with silica and carbon black provides particularly good results in view of braking performance on wet as well as on dry ground, without major tradeoff in rolling resistance.

[0035] In embodiments, the rubber composition comprises at least one coupling agent. The cross-linkable rubber composition may comprise in a range of > 1 phr to < 15 phr of at least one coupling agent. The coupling agent may be selected from a disulfide silane, a tetrasulfide silane, or a combination thereof. A specific example for a disulphide silane is bis-(3-triethoxysilylpropyl)disulfide (TESPD) available from Evonik Industries. A specific example for a tetrasulphide silane is bis-(3- triethoxysilylpropyljtetrasulfide (TESPT) available from Evonik Industries. The cross-linkable rubber composition may comprise first and second coupling agents, wherein the first coupling agent is a mercaptosilane and the second coupling agent is selected from a disulfide silane, a tetrasulfide silane, or a combination thereof. The ratio of the mercaptosilane to the silane may be in a range of > 2: 1 to < 10: 1, preferably in a range of > 2: 1 to < 4: 1. In the context of this invention a “mercaptosilane” denotes a silane coupling agent containing one or more mercapto group(s). Examples for mercaptosilanes are 3 -mercaptopropyl methyldimethoxysilane, 3- mercaptopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane and 3-octanoylthio-l- propyltriethoxysilane (NXT). Commercial examples for mercaptosilane are Silaan VP Si 363 Degussa available from Evonik Industries and NXT available from Momentive.

[0036] The cross-linkable rubber compositions may be sulfur-vulcanizable and / or peroxide -vulcanizable. If desired, additives can be added. Examples of usual additives are stabilizers, antioxidants, lubricants, fillers, dyes, pigments, flame retardants, conductive fibres and reinforcing fibres.

[0037] Another aspect of the present invention relates to a cross-linked rubber composition that is obtained by cross-linking a rubber composition according to the invention.

[0038] In an embodiment, the cross-linked rubber composition has a rebound at 23 °C, determined from rebound measurements according to ISO 4662, a range from > 13.8 % to < 14.5%. Such ranges are indicative for good wet grip.

[0039] In an embodiment, the cross-linked rubber composition has a a tan delta at 0°C, determined from dynamic mechanical analysis (DMA) measurements according to ISO 4664-1, frequency 10 Hz, 3% dynamic strain, in a range from > 0.8 to < 1.

[0040] In an embodiment, the cross-linked rubber composition has a tan delta at 30°C, determined from dynamic mechanical analysis (DMA) measurements according to ISO 4664-1, frequency 10 Hz, 3% dynamic strain, in a range from > 0.42 to < 0.6.

[0041] In other embodiments of the cross-linked rubber composition, may have a tan delta at 70 °C, determined from dynamic mechanical analysis (DMA) measurements according to ISO 4664-1, frequency 10 Hz, 3% dynamic strain, in a range of > 0.15 to < 0.26. Such ranges are indicative for good rolling resistance.

[0042] The present invention also relates to a method of preparing a tyre, comprising the steps of:

[0043] - providing a tyre assembly comprising a rubber composition according to the invention, and - cross-linking at least the rubber composition according to the invention in the tyre assembly.

[0044] The present invention also encompasses a tyre comprising a tyre tread, where the tyre tread comprises a cross-linked rubber composition according to the invention.

[0045] The present invention will be further described with reference to the following examples without wishing to be limited by them.

[0046] Methods:

[0047] Hardness Test: A hardness test was performed on a Zwick 3150 Shore A Hardness Tester according to DIN-53505 at 23°C. The hardness (in Shore A) for a test specimen was measured by making 5 determinations at different positions using a Durometer type A as described in the Hardness Shore A manual from Zwick. The determinations were at least 6.0 mm apart and at least 12 mm from any edge.

[0048] Tensile strength: Tensile strength analysis was performed for cured samples on a Zwick Z005 apparatus with a speed of 500 mm / min speed. Samples were cured at 160°C for 20 minutes and standard tensile specimens were cut from rubber sheet according to ISO 37 standard. Measuring tensile strength and force elongation properties via tensile method also determines modulus at various elongations i.e. 100% and 300% which indicates static stiffness.

[0049] Rebound: Rebound measurements were performed for cured samples on a Zwick / Roell 5109 Rebound Resilience Tester according to the standardised ISO4662 method at 23°C. Rebound measurements at 70°C were also performed on a Zwick / Roell 5109 Rebound Resilience Tester according to the ISO4662 method.

[0050] Temperature sweep by DMA: Dynamic mechanical analysis (DMA) analysis was performed for cured samples by Metravib DMA+450 in double shear mode according to ISO 4664-1. DMA was performed by temperature sweep at constant frequency 10 Hz with 3 % strain in a temperature range of -10°C to 80°C. DMA was also performed by temperature sweep at constant frequency 10 Hz with 0.1 % strain in a temperature range of -60°C to 0°C.

[0051] Example 1

[0052] In accordance with the preceding, cross-linkable rubber compositions were prepared according to the following table 1. In a first step, the rubber components were added and mixed, followed by a second step wherein the additives were added and mixed and a last step wherein the curing package was added. Composition “Ref’ is a comparative example and composition “Exp” is the composition according to the invention. Amounts for the components are given in phr.

[0053] Table 1: Composition of Examples:

[0054] Polybutadiene rubber BRI was nickel-catalyzed high cis rubber supplied by Synthos.

[0055] Polybutadiene rubber BR2 was Nd catalyzed 1,4 butadiene rubber Buna CB 25 with a cis content of min 96%, supplied by Arlanxeo.

[0056] SSBR 1 was EUPR3737 supplied by Versalis, a solution polymerized styrene-butadiene rubber (SSBR) with a bound styrene content of 36.5 w% and vinyl content of 43%. TDAE oil extended product was used.

[0057] SSBR 2 was SPRINTAN™ SLR 4601, manufactured by Synthos, a chemically modified SSBR, and had a styrene content of 21%, a vinyl content of 50%.

[0058] SSBR 3 was SPRINTAN™ SLR 4630, manufactured by Synthos, and had a styrene content of 25%, a vinyl content of 47.3%. TDAE oil extended product was used.

[0059] SSBR 4 was SPRINTAN™ 918 manufactured by Synthos, a functionalised SSBR and had a styrene content of 40%, a vinyl content of 26%. Oil extended product was used.

[0060] Carbon black 1 was CORAX® N-134, SAF high structure carbon black, manufactured by Orion Engineered Carbons.

[0061] Carbon black 2 was N-339, HAF-HS carbon black, manufactured by Columbian Chemicals Company.

[0062] Silica 1 was Highly Dispersible P type Silica (HDS, P) with a BET surface of 160, supplied by PPG Industries. Silica 2 was Zeosil HRS 1200MP with a BET surface of 200 from Solvay.

[0063] Silica 3 was Hi-Sil EZ200G amorphous precipitated silica with a BET surface area of 300 m2 / g, supplied by PPG Industries.

[0064] Silica 4 was MFILL 300 highly dispersible silica with a BET surface area of 300 m2 / g, supplied by Madhu Silica Pvt. Ltd..

[0065] Hydrocarbon resin was alpha-methylstyrene resin (copolymer of alpha-methylstyrene and styrene) SYLVARES SA85 supplied by Evonik Industries.

[0066] The terpene phenolic resin was Sylvatraxx 4202 with a molecular weight of 565 g / mol supplied by Kraton Corporation.

[0067] Silane coupling agtent 1 was TESPT supplied by Evonik Industries.

[0068] Silane coupling agtent 2 was TESPD supplied by Evonik Industries.

[0069] Durometer hardness (shore A) was measured to relate to physical properties.

[0070] Tensile strength was measured relating to durability.

[0071] Rebound at 70°C was measured relating to rolling resistance (RR).

[0072] Rebound at 23 °C was measured relating to wet grip.

[0073] Tan delta (0°C) was measured relating to wet grip.

[0074] Tan delta (30°C) was measured relating to dry grip.

[0075] Tan delta (70°C) was measured relating to rolling resistance (RR).

[0076] Table 2: Hardness test results:

[0077] The results show for the composition “Ref 2” compared to the reference composition “Ref 1” an increase in tensile strength, which is considered an indicator of better durability. It is assumed that this can be attributed to the blend of BR and SSBR. Table 3: Rebound and tan delta test results:

[0078] Tan delta at 0°C increased considerably for the compositions Exp 1 and Exp 2 comprising silica having a BET surface area of 300 m2 / g, which is a well-known indicator of an increase in the wet grip. Also, a lower rebound value at 23 °C relates to an improvement in wet grip. Tan delta at 30°C increased, which is a well-known indicator of an increase in dry grip. The indicator of rolling resistance (RR), tan delta at 70°C, illustrates that rolling resistance was maintained compared to the references. In summary, the results illustrate an improvement in wet braking and dry braking, without compromising rolling resistance. The rubber composition thus is usable for a summer tread compound with better grip performance in dry and wet condition. Without being bound to a specific theory, it is believed that this results from a combination of a high surface silica filler with carbon black in a blend of polybutadiene rubber and solution polymerized styrene-butadiene rubber with high styrene content.

Claims

Patent claims1. A cross-linkable rubber composition, the cross-linkable rubber composition comprising, per hundred parts by weight of rubber (phr):100 phr of a blend of polybutadiene rubber (BR) and solution polymerized styrenebutadiene rubber (SSBR), a filler, and a resin, wherein the composition comprises:> 10 phr to < 35 phr of a polybutadiene rubber and> 65 phr to < 90 phr of a solution polymerized styrene -butadiene rubber having a styrene content in a range of 35 % to 45 % and a vinyl content in a range of 10% to 30%, determined by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy according to ISO 21561-2:2016,> 70 phr to < 100 phr of a silica filler having a BET surface area in a range of > 250 m2 / g to < 300 m2 / g, determined according to ASTM DI 993, and> 15 phr to < 50 phr of carbon black.

2. The rubber composition according to claim 1, wherein the silica filler has a BET surface area in a range of > 275 m2 / g to < 300 m2 / g, determined according to ASTM DI 993.

3. The rubber composition according to claim 1 or 2, wherein the composition comprises the silica filler in a range of > 75 phr to < 90 phr.

4. The rubber composition according to any one of the preceding claims, wherein the composition comprises carbon black in a range of > 20 phr to < 30 phr.

5. The rubber composition according to any one of the preceding claims, wherein the solution polymerized styrene -butadiene rubber has a styrene content in a range of 35 % to 45 % and a vinyl content in a range of 20% to 30%, determined by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy according to ISO 21561-2:2016.

6. The rubber composition according to any one of the preceding claims, wherein the composition comprises the solution polymerized styrene -butadiene rubber (SSBR) in a range of > 75 phr to < 90 phr.

7. The rubber composition according to any one of the preceding claims, wherein the composition comprises the polybutadiene rubber (BR) in a range of > 15 phr to < 25 phr.

8. The rubber composition according to any one of the preceding claims, wherein the composition comprises > 15 phr to < 35 phr, preferably > 20 phr to < 30 phr, of a resin selected from the group of alpha-methyl styrene resin, terpene resin, polyterpene resin, terpene phenolic resin, a C5 resin, C9 resin, dicyclopentadiene (DCPD) resin or a combination thereof, preferably of alpha-methyl styrene resin.

9. The rubber composition according to any one of the preceding claims, wherein the composition comprises:> 10 phr to < 35 phr, preferably > 15 phr to < 25 phr, of BR;> 65 phr to < 90 phr, preferably > 75 phr to < 90 phr, of a SSBR, having a styrene content in a range of 35 % to 45 % and a vinyl content in a range of 10 % to 30%, preferably of 20 % to 30%, determined by attenuated total reflectance Fourier transform infrared (ATR- FTIR) spectroscopy according to ISO 21561-2:2016;> 70 phr to < 100 phr, preferably > 75 phr to < 90 phr, of the silica fdler, having a BET surface area in a range of > 250 m2 / g to < 300 m2 / g (according to ASTM D1993);> 15 phr to < 35 phr, preferably > 20 phr to < 30 phr, of carbon black, and a resin, optionally > 15 phr to < 35 phr, preferably > 20 phr to < 30 phr, of the resin, preferably alpha-methyl styrene resin.

10. A cross-linked rubber composition, characterised in that it is obtained by cross-linking a rubber composition according to any one of claims 1 to 9.

11. The cross-linked rubber composition according to claim 10, having a rebound at 23 °C, determined from rebound measurements according to ISO 4662, in a range from > 13.8 % to < 14.5%.

12. The cross-linked rubber composition according to any one of claims 10 or 11, having a tan delta at 0°C, determined from dynamic mechanical analysis (DMA) measurements according to ISO 4664-1, frequency 10 Hz, 3% dynamic strain, in a range from > 0.8 to < 1.

13. The cross-linked rubber composition according to any one of claims 10 to 12, having a tan delta at 30°C, determined from dynamic mechanical analysis (DMA) measurements according to ISO 4664-1, frequency 10 Hz, 3% dynamic strain, in a range from > 0.42 to < 0.6.

14. A method of preparing a tyre, comprising the steps of:- providing a tyre assembly comprising a rubber composition according to any one of claims 1 to 9,and- cross-linking at least the rubber composition according to any one of claims 1 to 9 in the tyre assembly.

15. A tyre comprising a tyre tread, characterised in that the tyre tread comprises a cross-linked rubber composition according to any one of claims 10 to 13.

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