阅读说明：本技术 充气轮胎 (Pneumatic tire ) 是由 J.M.F.C.塔翁 B.阿伦斯 J-L.M.F.托马斯 R.J.R.梅尔施 T.G.贝纳 于 2019-09-03 设计创作，主要内容包括：本发明涉及一种充气轮胎,其包含纤维帘线补强橡胶组件,该橡胶组件包含接触橡胶组合物的纤维帘线,该橡胶组合物包含：20至45 phr的溶液聚合苯乙烯-丁二烯橡胶,其具有5至25重量%的结合苯乙烯含量、基于丁二烯含量计5至40重量%的乙烯基-1,2含量、以及-85至-50℃的Tg；55至80 phr的聚异戊二烯橡胶,其选自天然橡胶和合成聚异戊二烯橡胶；20至60 phr的填料,其选自炭黑、二氧化硅和预疏水化二氧化硅；1至10 phr的树脂,其选自氨基甲酸类树脂、烷基酚醛树脂和酚醛树脂；和0.5至5 phr的亚甲基给予体。(The present invention relates to a pneumatic tire comprising a fiber cord reinforced rubber component comprising a fiber cord contacting a rubber composition comprising: from 20 to 45 phr of a solution polymerized styrene-butadiene rubber having a bound styrene content of from 5 to 25 weight percent, a vinyl-1, 2 content of from 5 to 40 weight percent, based on the butadiene content, and a Tg of from-85 to-50 ℃; 55 to 80 phr of a polyisoprene rubber selected from natural rubber and synthetic polyisoprene rubber; 20 to 60 phr of a filler selected from carbon black, silica and pre-hydrophobized silica; 1 to 10 phr of a resin selected from the group consisting of a urethane resin, an alkyl phenol-formaldehyde resin, and a phenol-formaldehyde resin; and 0.5 to 5 phr of methylene donor.)

1. A pneumatic tire characterized by comprising a fiber cord-reinforced rubber component, said rubber component characterized by comprising a fiber cord contacting a rubber composition, said rubber composition characterized by comprising:

from 20 to 45 phr of a solution polymerized styrene-butadiene rubber having a bound styrene content of from 5 to 25 weight percent, a vinyl-1, 2 content of from 5 to 40 weight percent, based on the butadiene content, and a Tg of from-85 to-50 ℃;

55 to 80 phr of a polyisoprene rubber selected from natural rubber and synthetic polyisoprene rubber;

20 to 60 phr of a filler selected from carbon black, silica and pre-hydrophobized silica;

1 to 10 phr of a resin selected from the group consisting of a urethane resin, an alkyl phenol-formaldehyde resin, and a phenol-formaldehyde resin; and

0.5 to 5 phr of methylene donor.

2. The pneumatic tire of claim 1, wherein the solution polymerized styrene-butadiene rubber is functionalized with alkoxysilane groups and at least one of primary amino groups and thiol groups.

3. The pneumatic tire of claim 2, wherein said filler comprises carbon black and silica.

4. Pneumatic tire according to claim 2, characterized in that the resin comprises a phenolic resin, an alkyl phenolic resin and a carbamic resin derived from n-butyl carbamate and formaldehyde.

5. The pneumatic tire of claim 4, characterized in that said assembly is further characterized by comprising polyester cords in contact with said rubber composition.

6. A pneumatic tire as in claim 5, wherein said rubber component is a carcass ply.

7. Pneumatic tire according to claim 2, characterized in that the filler is a pre-hydrophobized silica.

8. Pneumatic tire according to claim 7, characterized in that the pre-hydrophobized silica is pre-treated with at least one silane selected from the group consisting of alkylsilanes, alkoxysilanes, organoalkoxysilyl polysulfides and organomercaptoalkoxysilanes.

9. Pneumatic tire according to claim 7, characterized in that the pre-hydrophobized silica is further pre-treated with a dispersing aid selected from the group consisting of fatty acids, diethylene glycol, polyethylene glycol, fatty acid esters of hydrogenated or unhydrogenated C5 or C6 saccharides, and polyoxyethylene derivatives of fatty acid esters of hydrogenated or unhydrogenated C5 or C6 saccharides.

10. A pneumatic tyre as claimed in claim 7, characterized in that said resin is an at least partially reacted mixture of: 1) a urethane resin derived from n-butyl carbamate and formaldehyde, and 2) a novolac resin derived from phenol and formaldehyde.

Technical Field

The present invention relates to a pneumatic tire. In particular, the present invention relates to a pneumatic tire comprising a fiber cord reinforced rubber component.

Background

Traditionally, the carcass ply assembly of a tire is the cord reinforcement element of the tire carcass. Two or more carcass ply assemblies are typically used in a tire carcass. The carcass ply assembly itself is conventionally a plurality of cord reinforcement assemblies in which the cords are embedded in a rubber composition commonly referred to as ply coat (ply coat). The cord coat rubber compositions are conventionally applied by calendering the rubber onto a plurality of cords as they pass over, around and through a relatively large heated rotating metal cylindrical roll. Such carcass ply components for tires, as well as calendering methods for applying rubber composition skim coats, are well known to those skilled in the art. The same applies to the overlay of the tire belt, which is also formed of fiber cords and treated in a similar manner to the carcass ply.

The cord ply skim composition and the cap ply skim composition can have a positive impact on the fuel efficiency of the tire. There is therefore a continuing need for improved ply skim and overlay skim compositions.

Disclosure of Invention

The present invention relates to a pneumatic tire comprising a fiber cord reinforced rubber component comprising a fiber cord contacting a rubber composition comprising:

from 20 to 45 phr of a solution polymerized styrene-butadiene rubber having a bound styrene content of from 5 to 25 weight percent, a vinyl-1, 2 content of from 5 to 40 weight percent, based on the butadiene content, and a Tg of from-85 to-50 ℃;

55 to 80 phr of a polyisoprene rubber selected from natural rubber and synthetic polyisoprene rubber;

20 to 60 phr of a filler selected from carbon black, silica and pre-hydrophobized silica;

1 to 10 phr of a resin selected from the group consisting of a urethane resin, an alkyl phenol-formaldehyde resin, and a phenol-formaldehyde resin; and

0.5 to 5 phr of methylene donor.

Specifically, the invention discloses the following technical scheme:

scheme 1. a pneumatic tire comprising a fiber cord reinforced rubber component comprising a fiber cord contacting a rubber composition comprising:

from 20 to 45 phr of a solution polymerized styrene-butadiene rubber having a bound styrene content of from 5 to 25 weight percent, a vinyl-1, 2 content of from 5 to 40 weight percent, based on the butadiene content, and a Tg of from-85 to-50 ℃;

55 to 80 phr of a polyisoprene rubber selected from natural rubber and synthetic polyisoprene rubber;

20 to 60 phr of a filler selected from carbon black, silica and pre-hydrophobized silica;

1 to 10 phr of a resin selected from the group consisting of a urethane resin, an alkyl phenol-formaldehyde resin, and a phenol-formaldehyde resin; and

0.5 to 5 phr of methylene donor.

Scheme 2. the pneumatic tire of scheme 1, wherein the solution polymerized styrene-butadiene rubber is functionalized with alkoxysilane groups and at least one of primary amino and thiol groups.

Scheme 3. the pneumatic tire of scheme 2, wherein the filler comprises carbon black and silica.

Scheme 4. the pneumatic tire of scheme 2, wherein the resin comprises a phenolic resin, an alkyl phenolic resin, and a carbamate resin derived from n-butyl carbamate and formaldehyde.

Scheme 5 the pneumatic tire of scheme 4, wherein the assembly further comprises polyester cords in contact with the rubber composition.

Scheme 6. the pneumatic tire of scheme 5, wherein the rubber component is a carcass ply.

Scheme 7. the pneumatic tire of scheme 2, wherein the filler is a pre-hydrophobized silica.

Scheme 8. the pneumatic tire of scheme 7, wherein the pre-hydrophobated silica is pre-treated with at least one silane selected from the group consisting of alkylsilanes, alkoxysilanes, organoalkoxysilyl polysulfides, and organomercaptoalkoxysilanes.

Scheme 9. the pneumatic tire of scheme 7, wherein the pre-hydrophobated silica is further pre-treated with a dispersing aid selected from the group consisting of fatty acids, diethylene glycol, polyethylene glycol, fatty acid esters of hydrogenated or unhydrogenated C5 or C6 saccharides, and polyoxyethylene derivatives of fatty acid esters of hydrogenated or unhydrogenated C5 or C6 saccharides.

Scheme 10. the pneumatic tire of scheme 7, wherein the resin is an at least partially reacted mixture of: 1) a urethane resin derived from n-butyl carbamate and formaldehyde, and 2) a novolac resin derived from phenol and formaldehyde.

Scheme 11 the pneumatic tire of scheme 10, wherein the assembly further comprises nylon cords contacting the rubber composition.

Scheme 12. the pneumatic tire of scheme 11, wherein the component is a cap layer.

Drawings

Figure 1 shows a cross-sectional view of a tire of the present invention.

Detailed Description

The present invention discloses a pneumatic tire comprising a fiber cord reinforced rubber component comprising a fiber cord contacting a rubber composition comprising:

from 20 to 45 phr of a solution polymerized styrene-butadiene rubber having a bound styrene content of from 5 to 25 weight percent, a vinyl-1, 2 content of from 5 to 40 weight percent, based on the butadiene content, and a Tg of from-85 to-50 ℃;

55 to 80 phr of a polyisoprene rubber selected from natural rubber and synthetic polyisoprene rubber;

20 to 60 phr of a filler selected from carbon black, silica and pre-hydrophobized silica;

1 to 10 phr of a resin selected from the group consisting of a urethane resin, an alkyl phenol-formaldehyde resin, and a phenol-formaldehyde resin; and

0.5 to 5 phr of methylene donor.

Fig. 1 shows a schematic cross section of a tyre 1 according to one embodiment of the present invention. The tire 1 has a tread 10, an inner liner 13, a belt structure 11 comprising a plurality of belts covered by a radially outward cover layer 12, one or more carcass plies 9, two sidewalls 2 and two bead regions 3 comprising apex (bead filler apexes) 5 and beads 4. The exemplary tire 1 is, for example, suitable for mounting on a rim of a vehicle (e.g., a truck or passenger car). The carcass ply 9 comprises a pair of axially opposite ends 6, each of which is fixed to a respective one of the beads 4. Each axial end 6 of the carcass ply 9 is turned up and around the respective bead 4 to a position sufficient to anchor each axial end 6. The carcass ply 9 is a rubberized ply having a plurality of substantially parallel carcass reinforcing members made of a material such as polyester, rayon or similar suitable organic polymeric compounds. The embodiment of fig. 1 shows one carcass ply 9; two or more plies may be used. The turned-up portion 6 of the carcass ply 9 may engage the axially outer surfaces of the two flippers 8 and the axially inner surfaces of the two chippers 7. As shown in fig. 1, the exemplary tread 10 has circumferential grooves 14 that each substantially define a U-shaped opening in the tread 10. The main portion of tread 10 may be formed from tread band, which may be any suitable tread band or bands.

The overlay and ply are rubberized using a rubber composition. The cover layer is rubberized with the ply layer by contacting the fiber cords with a rubber composition by calendering or other methods known in the art.

The rubber composition comprises 20 to 45 phr of a styrene-butadiene rubber having a glass transition temperature (Tg) of-85 ℃ to-50 ℃. In one embodiment, the styrene-butadiene rubber has a glass transition temperature of from-70 to-55 ℃. Reference to the glass transition temperature or Tg (where mentioned herein) of an elastomer or elastomer composition represents the glass transition temperature(s) of the respective elastomer or elastomer composition in its uncured state or, in the case of an elastomer composition, may be in a cured state. The Tg may suitably be determined as the mid-point of the peak by Differential Scanning Calorimetry (DSC) at a temperature rise rate of 10 ℃/minute, for example according to ASTM D7426 or equivalent.

The styrene-butadiene rubber may be functionalized with various functional groups, or the styrene-butadiene rubber may be unfunctionalized. In one embodiment, the styrene-butadiene rubber is functionalized with alkoxysilane groups and at least one of primary amine groups and thiol groups. In one embodiment, the styrene-butadiene rubber is obtained by copolymerizing styrene and butadiene, characterized in that the styrene-butadiene rubber has primary amino groups and/or thiol groups and alkoxysilyl groups, which are bonded to the polymer chain. In one embodiment, the alkoxysilyl group is an ethoxysilyl group. In one embodiment, the styrene-butadiene rubber is not functionalized.

In one embodiment, the styrene-butadiene rubber has a bound styrene content of 5 to 25 weight percent. In one embodiment, the styrene-butadiene rubber has a bound styrene content of 10 to 20 weight percent. In one embodiment, the styrene-butadiene rubber has a vinyl 1,2 content of 5 to 40 weight percent, based on the butadiene content of the polymer. In one embodiment, the styrene-butadiene rubber has a vinyl 1,2 content of from 25 to 35 weight percent, based on the butadiene content of the polymer.

In a suitably functionalized styrene-butadiene rubber, the alkoxysilane, primary amino group, and/or thiol group may be bonded to any of the polymerization initiating terminal, polymerization terminating terminal, main chain and side chain of the styrene-butadiene rubber as long as it is bonded to the styrene-butadiene rubber chain. However, the alkoxysilane, primary amino group and/or thiol group are preferably introduced to the polymerization initiating terminal or the polymerization terminating terminal because energy disappearance at the polymer terminal is suppressed, thereby improving the hysteresis loss characteristics.

The styrene-butadiene rubber can be produced by the following method: styrene and butadiene are polymerized in a hydrocarbon solvent by anionic polymerization using an organic alkali metal and/or an organic alkaline earth metal as an initiator, a terminator compound having a primary amino group protected with a protecting group and/or a thiol group protected with a protecting group and an alkoxysilyl group is added to react with the living polymer chain ends when the polymerization is substantially complete, and then deblocking is carried out, for example, by hydrolysis or other suitable procedures. In one embodiment, the styrene-butadiene rubber may be manufactured as disclosed in U.S. 7,342,070. In another embodiment, styrene-butadiene rubber may be manufactured as disclosed in WO 2007/047943.

In one embodiment, a solution polymerized styrene-butadiene rubber is disclosed in WO 2007/047943 and is functionalized with alkoxysilane groups and thiols and comprises the reaction product of a living anionic polymer and a silane-thioether modifier represented by the formula:

(R⁴O)_xR⁴ _ySi-R⁵-S-SiR⁴ ₃

wherein Si is silicon; s is sulfur; o is oxygen; x is an integer selected from 1,2 and 3; y is an integer selected from 0, 1 and 2; x + y = 3; r⁴Are the same or different and are (C)₁-C₁₆) An alkyl group; and R' is aryl or alkylaryl, or (C)₁-C₁₆) An alkyl group. In one embodiment, R⁵Is (C)₁-C₁₆) An alkyl group. In one embodiment, each R is⁴The radicals are identical or different and are each independently C₁-C₅Alkyl, and R⁵Is C₁-C₅An alkyl group.

Suitable styrene-butadiene rubbers functionalized with alkoxysilane groups and thiol groups are commercially available, for example Sprintan SLR 3402 from Trinseo.

Other suitable styrene-butadiene rubbers include Nipol NS612 from Zeon.

The Rubber composition further comprises 55 to 80 phr of a natural Rubber or synthetic polyisoprene having a cis 1,4 content of at least 96 wt%, such as Natsyn 2200 from The Goodyear Rubber & Tire co.

The rubber composition also includes an in situ resin. An in situ resin is formed in the rubber composition and involves the reaction of a methylene acceptor with a methylene donor. The term "methylene donor" is intended to mean a compound capable of reacting with a methylene acceptor and generating a resin in situ. Examples of methylene donors suitable for use in the present invention include hexamethylenetetramine, hexamethoxymethylmelamine, hexaethoxymethylmelamine, imino-methoxymethylmelamine, imino-isobutoxymethylmelamine, lauryloxymethylpyridinium chloride, ethoxymethylpyridinium chloride trioxane, and hexamethoxymethylmelamine. Furthermore, the methylene donor may be an N-substituted oxymethyl melamine of the formula:

wherein X is hydrogen or an alkyl group having 1 to 8 carbon atoms, R₁、R₂、R₃、R₄And R₅Independently selected from hydrogen, alkyl groups having from 1 to 8 carbon atoms, the group-CH 2OX or condensation products thereof. Specific methylene donors include hexa- (methoxymethyl) melamine, N ', N "-trimethyl/N, N ', N" -trimethylol melamine, hexamethylol melamine, N ', N "-dimethylol melamine, N-methylol melamine, N ' -dimethylol melamine, N ', N" -tris (methoxymethyl) melamine, and N, N ' N "-tributyl-N, N ', N" -trimethylol-melamine. The N-methylol derivatives of melamine are prepared by known methods.

The amount of methylene donors that may be present in the rubber composition may vary. In one embodiment, the methylene donor is present in an amount of about 1 to 5 phr.

The term "methylene acceptor" is known to those skilled in the art and is used to describe the reactant with which the methylene donor reacts to form what is believed to be a hydroxymethyl monomer. The methylol monomers produce resins by condensation forming methylene bridges. The initial reaction that contributes to the subsequent formation of the methylene bridge is a methylene donor, where the other reactant is a methylene acceptor. Representative compounds that may be used as methylene acceptors include, but are not limited to, resorcinol derivatives, monohydric phenols and derivatives thereof, dihydric phenols and derivatives thereof, polyhydric phenols and derivatives thereof, unmodified novolak resins, modified novolak resins, phenolic resins, resorcinol novolak resins, and mixtures thereof. Examples of methylene acceptors include, but are not limited to, u.s. 6,605,670; U.S. 6,541,551; U.S. 6,472,457; U.S. 5,945,500; U.S. 5,936,056; U.S. 5,688,871; U.S. 5,665,799; U.S. 5,504,127; U.S. 5,405,897; U.S. 5,244,725; U.S. 5,206,289; U.S. 5,194,513; U.S. 5,030,692; U.S.4,889,481; U.S.4,605,696; those disclosed in U.S.4,436,853 and U.S.4,092,455. Examples of modified novolak resins include, but are not limited to, cashew oil modified novolak resins, tall oil modified novolak resins, and alkyl modified novolak resins. In one embodiment, the methylene acceptor is a reactive phenolic resin. Suitable reactive phenolic resins include SMD 30207 from the SI Group and SP-1068 from the SI Group.

Other examples of methylene acceptors include activated phenols obtained by ring substitution and cashew oil-modified novolac-type phenolic resins. Representative examples of activated phenols obtained by ring substitution include resorcinol, cresol, tert-butyl phenol, isopropyl phenol, ethyl phenol, and mixtures thereof. Cashew oil-modified novolac-type phenolic resins are available under the designation SP6700 from Schenectady Chemicals inc. The modification ratio of the oil based on the total novolac type phenol resin may be 10 to 50%. To produce a novolak-type phenolic resin modified with cashew oil, various methods can be employed. For example, phenols such as phenol, cresol and resorcinol can be reacted with aldehydes such as formaldehyde, paraformaldehyde and benzaldehyde using an acid catalyst. Examples of the acid catalyst include oxalic acid, hydrochloric acid, sulfuric acid, and p-toluenesulfonic acid. After the catalytic reaction, the resin is modified with the oil.

The amount of methylene acceptor in the secondary rubber compound may vary. In one embodiment, the amount of methylene acceptor is from 0.5 to 5 phr.

The rubber composition also contains 0.5 to 10 phr of a urethane resin, also known as a urethane resin or a urethane-aldehyde resin. Suitable urethane resins can be used, for example, US 2015/0119527; US 5,559,169; the method described in US 8,759,471.

In one embodiment, the carbamate resin is derived from a monofunctional or polyfunctional aldehyde A, and an organic compound C having at least one carbamate group-O-CO-NH₂And an organic group, wherein the group may be a monovalent group R selected from linear, branched or cyclic aliphatic groups having from 1 to 30 carbon atoms and aralkyl groups, or a divalent organic group-R-A bisalkyl aryl group of 8 to 30 carbon atoms.

In one embodiment, R has 2 to 8 carbon atoms.

In one embodiment, aliphatic urethanes are used as compound C, which are selected from the group consisting of ethyl carbamate, butyl carbamate, hexyl carbamate, and 2-ethylhexyl carbamate.

In one embodiment, an araliphatic carbamate is used as compound C, which is selected from benzyl carbamate and α -dimethylbenzyl carbamate.

In one embodiment, biscarbamates are used as compound C, which is selected from ethylene biscarbamate, 1, 2-propylene biscarbamate, 1, 3-propylene biscarbamate and 1, 4-butylene biscarbamate.

In one embodiment, biscarbamates are used as compound C, which is selected from xylylene biscarbamates and tetramethylxylylene biscarbamates.

In one embodiment, a monofunctional aldehyde is used as aldehyde a, which is selected from the group consisting of formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, n-valeraldehyde, and n-hexanal.

In one embodiment, a multifunctional aldehyde is used as aldehyde a, which is selected from the group consisting of glyoxal, malondialdehyde, succindialdehyde, and glutaraldehyde.

In one embodiment, the carbamate-based resin is derived from n-butyl carbamate (also known as butyl carbamate) and formaldehyde.

Suitable urethane resins are commercially available from Allnex as Alnovol UF410 and the like.

In one embodiment, the carbamate resin may be in the form of a mixture of the first carbamate resin and a novolac resin, for example as described in US 2012/0095152. In one embodiment, the mixture of a carbamate resin and a novolac resin is a mixture of a carbamate-aldehyde resin UA prepared by condensation of aldehyde A1 and an alkyl carbamate U, and a novolac PA prepared by reaction of aldehyde A2 with a phenolic compound P, wherein the aldehydes A1 and A2 are independently selected from the group consisting of formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde and isobutyraldehyde, the alkyl carbamates U are selected from the group consisting of ethyl, butyl, 2-ethylhexyl and decyl carbamates, the phenolic compounds P are selected from the group consisting of phenol, o-, m-and P-cresol, o-, m-and P-monoalkylphenols, wherein the alkyl group contains at most 18 carbon atoms and the mass ratio of urethane-aldehyde resin UA to novolak PA is 90 g:10 g to 10 g:90 g.

In one embodiment, the mixture of the urethane resin and the novolac resin may be an at least partially reacted mixture of: 1) a urethane resin derived from n-butyl carbamate and formaldehyde, and 2) a novolac resin derived from phenol and formaldehyde. A suitable mixture of a carbamate resin and a novolac resin is available as Alnovol PN760 from Allnex.

Typically, the rubber composition comprises from 1 to 10 phr of a resin selected from the group consisting of a urethane resin, an alkyl phenol resin and a phenol resin.

Also included in the rubber composition is 20 to 60 phr of a filler selected from carbon black, silica, and pre-hydrophobated silica.

In one embodiment, the filler comprises a pre-hydrophobized precipitated silica. By pre-hydrophobated is meant that the silica is pre-treated, i.e., hydrophobated, by treating with at least one silane to pre-hydrophobated precipitated silica prior to its addition to the rubber composition. Suitable silanes include, but are not limited to, alkylsilanes, alkoxysilanes, organoalkoxysilyl polysulfides, and organomercaptoalkoxysilanes.

In an alternative embodiment, the pre-hydrophobated precipitated silica may be pre-treated with a silica coupling agent comprising, for example, an alkoxyorganomercaptoalkoxy silane or a combination of an alkoxysilane and an organomercaptoalkoxy silane, followed by blending the pre-treated silica with the rubber, rather than reacting the precipitated silica with the silica coupling agent in situ in the rubber. See, for example, U.S. patent No. 7,214,731.

The pre-hydrophobized precipitated silica may optionally be treated with a silica dispersing aid. Such silica dispersing aids may include polyoxyethylene derivatives of glycols such as fatty acids, diethylene glycol, polyethylene glycol, fatty acid esters of hydrogenated or unhydrogenated C5 or C6 saccharides, and fatty acid esters of hydrogenated or unhydrogenated C5 or C6 saccharides.

Exemplary fatty acids include stearic acid, palmitic acid, and oleic acid.

Exemplary fatty acid esters of hydrogenated or unhydrogenated C5 and C6 saccharides (e.g., sorbose, mannose, and arabinose) include, but are not limited to, sorbitan oleate esters, such as sorbitan monooleate, dioleate, trioleate, and sesquioleate, and sorbitan esters of lauric, palmitic, and stearic fatty acids. Exemplary polyoxyethylene derivatives of fatty acid esters of hydrogenated and unhydrogenated saccharides C5 and C6 include, but are not limited to, polysorbates and polyoxyethylene sorbitan esters, which are similar to the fatty acid esters of hydrogenated and unhydrogenated saccharides described above, except that an ethylene oxide group is placed on each hydroxyl group.

If used, the optional silica dispersing aid is present in an amount of about 0.1 to about 25 weight percent based on the weight of the silica, with about 0.5 to about 20 weight percent being suitable, and about 1 to about 15 weight percent based on the weight of the silica also being suitable.

For various pretreated precipitated silicas see, for example, U.S. patent nos. 4,704,414, 6,123,762, and 6,573,324.

Common siliceous pigments that can be used in rubber compounds include conventional pyrogenic and precipitated siliceous pigments (silica). In one embodiment, precipitated silica is used. Conventional siliceous pigments used in the present invention are precipitated silicas such as those obtained by the acidification of a soluble silicate (e.g., sodium silicate).

Such conventional silicas can be characterized, for example, by having a BET surface area measured using nitrogen. In one embodiment, the BET surface area may be from about 40 to about 600 square meters per gram. In another embodiment, the BET surface area may be from about 80 to about 300 square meters per gram. BET for measuring surface areaThe method is described inJournal of the American Chemical SocietyVolume 60, page 304 (1930).

Conventional silicas may also be characterized by having a Dibutylphthalate (DBP) absorption value of about 100 to about 400, or about 150 to about 300.

Conventional silicas can be expected to have an average final particle size, as determined by electron microscopy, of, for example, 0.01 to 0.05 microns, although the size of the silica particles can be even smaller, or possibly larger.

Various commercially available silicas may be used, such as, by way of example only and not limitation herein, silicas commercially available from PPG Industries under the Hi-Sil trademark with designations 210, 243, etc.; silica available from Solvay under the names of, for example, Z1165MP, Z165GR, and Zeosil Premium 200 MP; and silicas available from Degussa AG under the names VN2 and VN3, for example, and the like.

Conventional carbon black may be used. Representative examples of such carbon blacks include N110, N121, N134, N220, N231, N234, N242, N293, N299, S315, N326, N330, M332, N339, N343, N347, N351, N358, N375, N539, N550, N582, N630, N642, N660, N650, N683, N754, N762, N765, N774, N787, N907, N908, N990 and N991. These carbon blacks have iodine absorption values of 9 to 145 g/kg and DBP values of 34 to 150 cm³100 g of the total weight. Blends of carbon blacks, particularly combinations of relatively high and low surface area carbon blacks, may be used to achieve the desired hysteresis, dynamic stiffness, and tear strength.

In one embodiment, the rubber composition may optionally contain conventional sulfur containing organosilicon compounds. In one embodiment, the sulfur containing organosilicon compound is a 3,3' -bis (trimethoxy or triethoxysilylpropyl) polysulfide. In one embodiment, the sulfur containing organosilicon compound is 3,3 '-bis (triethoxysilylpropyl) disulfide and/or 3,3' -bis (triethoxysilylpropyl) tetrasulfide.

The amount of the optional sulfur containing organosilicon compound in the rubber composition varies depending on the level of other additives used. Generally, the amount of the compound is from 0.5 to 20 phr. In one embodiment, the amount is from 1 to 6 phr.

It is recognized that conventional compounding ingredients can be used to prepare the rubber composition. The rubber composition in contact with the fiber cords in the finished tire is sulfur cured as a component of the tire. For example, the sulfur cured ply coat rubber composition may contain conventional additives including reinforcing agents, fillers, peptizers, pigments, stearic acid, accelerators, sulfur-vulcanizing agents, antiozonants, antioxidants, processing oils, activators, initiators, plasticizers. Waxes, prevulcanization inhibitors, extender oils, and the like. Representative of conventional accelerators may be, for example, amines, guanidines, thioureas, thiols, thiurams, sulfenamides, dithiocarbamates and xanthates, which are typically added in amounts of about 0.2 to about 3 phr. Representative sulfur-vulcanizing agents include elemental sulfur (free sulfur) or sulfur-donating vulcanizing agents, such as amine disulfides, polymeric polysulfides, or sulfur olefin adducts. The amount of sulfur-vulcanizing agent varies depending on the type of rubber, particularly the type of sulfur-vulcanizing agent, but is generally from about 0.1 phr to about 3phr, preferably from about 0.5 phr to about 2 phr. Representative antidegradants that may be in the rubber composition include monophenols, bisphenols, thiobisphenols, polyphenols, hydroquinone derivatives, phosphites, phosphate blends, thioesters, naphthylamines, bisphenolamines and other diarylamine derivatives, para-phenylenediamines, quinolines and blended amines. Antidegradants are generally used in amounts of about 0.1 to about 10 phr, preferably about 2 to 6 phr. However, amine-based antidegradants are not preferred in the practice of the present invention. Representative of peptizers that can be used are pentachlorophenol, which can be used in an amount of about 0.1 to 0.4 phr, preferably about 0.2 to 0.3 phr. Representative of processing oils useful in the rubber compositions of the present invention include, for example, aliphatic, naphthenic and aromatic oils. Processing oils may be used in conventional amounts of about 0 to about 30 phr, with about 0 to about 10 phr being more generally preferred. The initiators are generally used in conventional amounts of from about 1 to 4 phr, preferably from about 2 to 3 phr.

The accelerators may be used in conventional amounts. In the case where only the primary accelerator is used, the amount is from about 0.5 to about 2 phr. In the case where a combination of two or more accelerators is used, the primary accelerator is typically used in an amount of 0.5 to 1.5 phr and the secondary accelerator is used in an amount of about 0.1 to 0.5 phr. Combinations of accelerators are known to produce synergistic effects. Suitable types of conventional accelerators are amines, disulfides, guanidines, thioureas, thiazoles, thiurams, sulfenamides, dithiocarbamates and xanthates. Preferably, the primary accelerator is a sulfenamide. If a secondary accelerator is used, it is preferably a guanidine, dithiocarbamate or thiuram compound.

In practice, cords of various compositions may be used for the carcass ply or overlay, such as, but not intended to be limited to, polyester, rayon, aramid, and nylon, and hybrid cords thereof. Such cords and their construction (whether monofilament or twisted filament) are well known to those skilled in the art.

The cords may be made of any fiber known in the art to be suitable for use in tires. Cord yarns are typically made in filament tow by extruding filaments from a polymer melt. Cords are made by drawing fibers into a yarn comprising a plurality of fibers, followed by twisting a plurality of such yarns into a cord. Such yarns may be treated with spin-finish to protect the filaments from abrasion against each other and against machine equipment, thereby ensuring good mechanical properties. In some cases, the yarn may be overcoated with a so-called adhesion activator prior to twisting the yarn into a cord. The adhesion activator typically comprises a polyepoxide for improving the adhesion of the cord to the rubber compound after dipping with a resorcinol-formaldehyde-latex (RFL) dip.

The treatment of the cord comprises treating the cord with an aqueous RFL emulsion comprising a resorcinol-formaldehyde resin and one or more elastomer latexes.

In one embodiment, the RFL may comprise resorcinol-formaldehyde resin, styrene-butadiene copolymer latex, vinylpyridine-styrene-butadiene terpolymer latex, and a blocked isocyanate.

In one embodiment, the cord may be initially treated with an aqueous emulsion comprising a polyepoxide, followed by an RFL treatment.

After treating the cord in RFL, or after initially treating in polyepoxide and subsequently RFL treating, the treated cord is incorporated into a ply layer along with a rubber composition to produce a fiber cord reinforced rubber component. In one embodiment, the rubber component is a carcass ply. In one embodiment, the rubber component is a cover layer.

The rubber component may be included in various types of tires including passenger tires, truck tires, motorcycle tires, medium truck tires, off-the-road tires, and aircraft tires.

Pneumatic tires conventionally include a generally annular casing having an outer circumferential tread adapted to fit into the ground-contacting space, beads, and sidewalls extending radially from the tread to the beads and connecting the tread and the beads. The tread may be constructed, shaped, molded and cured by various methods apparent to those skilled in the art.

The invention is further illustrated by the following non-limiting examples.