DE3034908A1 - Butyl rubber sealant compsn. for use inside tyres - contains crosslinking agent e.g. quinoid or phenolic resin and tackifier, e.g. polybutene - Google Patents

Abstract

A sealant compsn. for use in a tyre comprises the reaction prod. of a butyl rubber present solely as a copolymer of average viscosity mol. wt. above 100,000, a maturing agent for butyl-rubber and a tackifying agent which is compatible with the rubber. The compsn. has a tensile strength of at least 210 kPa, an extension of at least 600% and a crosslinking density such that the swelling index g the compsn. in toluene is 12-40, pref. 12-35. Also claimed is a tyre which is self sealing and incorporates the compsn. The compsn. automatical seals punctures in the tread within widely variable temp. conditions.

Description

description

The invention relates to a sealing means or a sealing compound (hereinafter always referred to as "sealing means" for the sake of simplicity), which is particularly suitable and contains or consists of vehicle tires made of a cured butyl rubber, which is only available in the form of a copolymer with a Molecular weight greater than 100,000, and one or more tackifiers, its tensile strength, elongation and crosslinking density so coordinated are that the properties required for tire sealants are obtained. The sealant of the present invention has been used as a self-sealing tire puncture sealant developed. As a tire sealant, it can be applied to the inner surface of a Rubber tire and it is used to cut punctures in the tread or to seal the profile area under widely varying temperature conditions (to close). The sealing means according to the invention is not only suitable, however as a tire sealant, but is also used for other purposesa under similar severe conditions or less severe conditions.

In order for the sealing (closing) of tire holes To be suitable (holes in tires), a sealant must be unique and exceptionally sophisticated combination of physical and chemical Fulfill criteria. It must help against aging, against decomposition and against flowing the high temperatures to which tires heat up under driving conditions in summer become, be constant. In the event that the intruding object is in the tread (the tire tread) remains while the tire is still in use, it must Sealing agent sufficient tack and fatigue resistance have to adhere to the object even if it is during the tire rotation is moved back and forth. In the event that the intruding object from the tread (the tire tread) is removed, the sealant must be able to get into to flow into the formed hole at the temperatures in winter and to seal it (to be locked).

Other properties required of a tire sealant are discussed in more detail below.

Since butyl rubber has a low air permeability, a high resistance against aging and has an easily controllable crosslink density always tried to use butyl rubber as a basis for tire sealants. An attempt as described, for example, in U.S. Patents 2,756,801, 2,765,018 and 2,782,829 was a single grade of butyl rubber to be used for the production of the sealant network and tackifier, Plasticizers and other more specific components, such as phenols or iron oxide, admitting in an effort to achieve the required balance of physical properties to achieve. However, sealants based on these patents have not found widespread acceptance, primarily because of these sealants at extreme temperatures (e.g. -29 ° C (-200F) to + 104 ° C (2200F)), exposed to tires do not perform satisfactorily.

In a second experiment with tire sealants based on Butyl rubber became a combination of high and low butyl rubbers Molecular weight used, which were crosslinked together to form a single elastomer network. Although it has been found that these sealants Over wide temperature ranges work just fine, the butyl rubber however, is low molecular weight. less commercially available than the high molecular weight butyl rubber, and sealants used for Partly based on butyl rubber with low molecular weight, are therefore less attractive.

One of the main difficulties in developing an acceptable one Tire sealant consists in having a single physical property such an agent will depend on a wide variety of chemical variables can. For example, in a sealant that generally depends on a cured, reinforced butyl rubber and a tackifier, one The only property, such as tensile strength, depends on the proportion of what is present Butyl rubber, the molecular weight and the mole percentage of unsaturation of the Butyl rubber, the amount of crosslinking agent used, the amount of reinforcing agent used and, to a certain extent, on the tackifiers used and on the applied curing and application methods. In the circumstances it is difficult to specify characteristic ranges for individual chemical variables, since the total physical properties of interest of the combined The effect of many variables. For example, it has been found that sealing agents, in which the existing proportion of butyl rubber is within a certain Range is, can be formulated so that they have the desired tensile properties own.

But it is also quite possible to use these properties outside of this Achieve range by adjusting the amount of crosslinking agent used and other variables.

It has now been found that improved (superior) sealants can be produced by appropriate adjustment of their compositions, around so control three key properties. It is with these three characteristics it is the tensile strength, the elongation and the crosslink density. The tensile strength refers to the maximum stress (force per unit area), the one Can withstand the sample of the sealing solder before it breaks (tears).

The elongation measures the relative increase in the lungs of a sample of the sealing material at the breaking point. The crosslink density is a molecular property which measures the concentration of the crosslinks present in the part of the crosslinking agent are present that have been listened to into a three-dimensional networked network is. It can be measured very easily by means of a swelling test in which the amount of solvent is determined by that present in a given sample of the sealant three-dimensional network is absorbed.

These three properties - the tensile strength, the elongation and the Network density - are important because of their relationship to the properties that a tire sealant must have in order to function properly. When the tensile strength of a sealant is too little, the sealant will flow below the typical Reifenbetriebsbedinguijgen and it is also "penetrated" by a perforated hole, when the piercing object is removed from the tire and it seals the hole not off. An acceptable sealant, therefore, must have sufficient tensile strength have in order to be resistant to this "unscrupulous".

When the elongation of a sealant is too low, several occur Defects. If an object, such as a nail, enters a tire, its Inside is coated with a sealant, the sealant should preferably adhere to the nail and form a tent-like structure that supports the nail surrounds. Through the Adhesion of the sealant to the nail this point is maintaining an air barrier at the perforation (the hole) supports and this also leads to the fact that the sealant through the nail is pulled into the pierced hole when the nail is removed. If the sealant has insufficient elongation, it is not in able to stretch (stretch) enough to form a tent. The sealant can then form a cap on the nail, i.e. a small part of the tip of the sealant surrounding the nail breaks away from the remainder of the sealant off and stick to the nail near its tip. This cap formation generally results in a poor seal while the nail is still in place located in the tire.

Another consequence of too little elongation is that in the case a large hole not enough sealant over the hole and into the hole can flow into it to create a seal when the penetrated into the tire Object is removed from it.

The network density of a polymer sealant determines how resistant the sealant is to permanent deformation. When the sealant If the crosslinking density is too high, it is too resistant to permanent deformation and the sealant is more likely to form a cap on a penetrated object instead of a tent, which has the consequences described above. When the crosslink density is too low, the centrifugal force causes the sealant at increased Temperatures creeps up or flows, resulting in insufficient sealant under the shoulder part of the tire. Too low a crosslinking density leads to it also to a low fatigue resistance of the sealant. the Fatigue resistance is an important prerequisite for an effective tire sealant, in particular in a situation where an object such as a Nail, penetrates a tire (pneumatic tire) and the tire then a considerable one Used for a period of time without removing the nail.

Usually the driver of the vehicle does not even notice the presence of the nail. The periodic contact between the pierced part of the tire and the road causes the nail to bend back and forth as the tire moves turns. Now suppose that the sealant formed a tent over the nail the sealing agent forming the tent is continuously stretched and relaxed, a process in which, with the passage of time, the cross-links break and the sealing agent is added has a tendency to flow away from the nail, thereby sealing against leakage destroyed by air.

Sealing means according to the invention contain or consist of hoarded Butyl rubbers, which are only available in the form of a copolymer with an average viscosity Molecular weight greater than 100,000 in combination with suitable tackifiers are present, the tensile strength, elongation and crosslinking density of the sealing device have been coordinated (adjusted) with one another in such a way that the above-described, Properties required by a sealant can be achieved. In general tensile strength, elongation and crosslinking density can be controlled very easily (controlled) by adjusting the proportion (fraction) of butyl rubber in the overall composition, by adjusting the amount of crosslinking agent used, the amount of reinforcing agent used, the molecular weight and the mole percentage the unsaturation of the butyl rubber and, to a lesser extent, that used Tackifier and treatment method applied. It has now been found that preferred sealing means for vehicle tires (pneumatic vehicle tires ) are those in which the tensile strength is greater than 2.11 kg / cm2 (30 psi) elongation be more than 600% and the degree of swelling (the swelling ratio) in toluene is between 12 and 40. Sealants with elongations of more than 8GO% and Have degrees of swelling (swelling ratios) within the range of 12 to 35 proved to be particularly suitable as a vehicle tire sealant and they are therefore particularly preferred.

Such sealing means can be made by adjustment of the butyl rubber so that it constitutes from about 13 to about 40 percent by weight of the total composition exclusively the crosslinking agent, by using a butyl rubber with a mole percentage of unsaturation between about 0.5 and about 2.5 and one Molecular weight from about 100,000 to about 450,000 and by using about 0.5 to about 6 phr of a quinoid crosslinking agent and from at least about 2 phr Carbon black, the abbreviation "phr" used here, stands for "parts by weight per 100 Ges ~ Tvile butyl rubber @@ Sealants containing 13 to 20 butyl rubber, 30 to 60 phr carbon black and 2 to 6 phr of a quinoid crosslinking agent are particularly preferred because they are easy can be prepared (mixed) in such a way that their properties are within the above specified ranges, and because they are the significant ones described below Have machining advantages. Sealing agent with tensile strengths, elongations and degrees of swelling (swelling ratios) within the ranges given above can also be produced (mixed) by adjusting the butyl rubber content, so that it is about 13 to about 50 weight percent of the total composition excluding the crosslinking agents by using a butyl rubber with a mole percentage of unsaturation between about 0.5 and about 2.5 and a molecular weight of about 100,000 to about 450,000 and by using from about 5 to about 25 phr of a bromomethylated phenolic resin -Htirters and at least 3 phr zinc oxide.

The invention is described below with reference to the enclosed Drawing explained in more detail. They show: FIG. 1 a perspective view of a Cross section of a vehicle tire (vehicle pneumatic tire) according to one embodiment of the invention in which the sealant layer is on the innermost surface the tire (pneumatic tire) is arranged behind the tread (the tire profile); and FIG. 2 shows a perspective view similar to FIG. 1 according to a second embodiment of the invention, in which the sealing agent layer according to the invention behind the Tread part (tire profile part) of the vehicle tire (pneumatic vehicle tire) and between an air-impermeable film, as is usually found in a tubeless one Tire (pneumatic tire) is used, and the cork body part of the tire (pneumatic tire) ongcs is arranged.

Dos copolymer network, which the sealing agents according to the invention Made of hardened butyl rubber, which gives strength and continuity. Under Butyl rubber are copolymers of 96 to 99.5% by weight isobutylene and 4 bis 0.5 wt .-% isoprene (Butyl IIR) and other rubber-like copolymers with a major proportion by weight (i.e. more than 50% by weight) of an isoolefin having 4 to 7 carbon atoms and a smaller proportion by weight of an open-chain conjugated diolefin to understand with 4 to 8 carbon atoms. The copolymer can consist of 70 up to 99.5% by weight of an isomonoolefin, such as isobutylene or ethylmethylethylene, copolymerized with 0.5 to 30% by weight of an open-chain conjugated diolefin, like isoprene; 1,3-butadiene; Piperylene; 2,3-dimethyl-butadiene-1,3; 1,2-dimethylbutadiene-1,3 (3-methyl-pentadiene-1,3); 1,3-dimethyl-butadiene-113; 1-ethyl-butadiene-1,3 (hexadiene-1,3); 1,4-dimethyl-butodiene-1,3 (hexadiene-2,4); thereby causing the copolymerization can in the usual way of the copolymerization of such monomeric materials.

The term "butyl rubber" as used herein also includes halogenated ones Butyl rubber, with the chlorobutyl and bromobutyl grades being the best known. It is generally believed that the halogen enters the butyl rubber molecule through Substitution at the allyl position in the diolefin moiety. Typical chlorobutyl rubbers contain about 1.0 to about 1.5 percent by weight of chlorine. The term "butylkoutschuk" includes also such butyl rubber types, in those è a conjugated diene functionality in the linear backbone has been added to the diolefin units.

Such conjugated diene butyls are disclosed in U.S. Patent 3,816 371 described.

The sealants of the present invention can be prepared (mixed or formulated) using any of the common grades of butyl rubber high molecular weight. These varieties have viscosity average molecular weights of more than 100,000 and generally their molecular weights are within of the range from 300,000 to 450,000. They are to be distinguished from the types of butyl rubber low molecular weight, the viscosity average molecular weights on the order of 1/10 that of high molecular weight butyl rubbers exhibit. The sealants according to the invention do not contain any types of butyl rubbers low molecular weight.

Representative examples of high molecular weight butyl rubbers are Butyl 065, Butyl 165, Butyl 268, Butyl 365, Butyl 077, Chlorobutyl 1066 and Chlorobutyl 1068, all available from Exxon Oil Company, as well as BUCAR 1000 NS, BUCAR 5000 NS, BUCAR 5000 S and BUCAR 6000 NS, all of from Cities Service Oil Company.

True, by using a butyl rubber with a molecular weight of more than about 450,000, the sealing qualities of the sealant fail but such a butyl rubber is comparatively difficult to dissolve and to combine with other components and difficult to apply using an air-free spray process. Therefore, the preferred range is the molecular weight of the high molecular weight butyl rubber is about 100 000 to about 450,000. A butyl rubber having a molecular weight within the The range from 300,000 to 450,000 has proven to be particularly advantageous for the production (formulation) of sealants with the desired tensile strength and elongation properties and is therefore particularly preferred.

The crosslinking of the butyl rubber can be effected using any of the known curing or crosslinking systems including the sulfur and sulfur-containing systems, quinoid systems and phenolic resin systems. For examples Hard materials that can additionally be used for halogenated butyl rubber include primary Amines and diamines, secondary diamines, zinc oxide combined with alkyldithiol carbamates, such as tetramethylthiuram disulfide, and 1,2-1, 3-dialkyl thioureas' Examples for a butyl rubber that contains a conjugated diene functionality Useful hardeners include polyfunctional dienophiles such as ethylene glycol dimethacrylate and trimethylol propane trimethacrylate.

Although butyl rubber using a vulcanization process (with sulfur and accelerators such as mercaptobenzothiazole) can be hardened, leads to such a hardening in a rubber that this with the expiry of the Time is degraded under the influence of oxygen or ultraviolet radiation. Such degradation can be partially prevented by using antioxidants, such as diphenyl-p-phenylenediamine, phenyl-ß-nophthylamine and hydroquinone, as well Antiozonants such as N, N'-di (2-octyl) -p-phenylenediamine and N- (1,3-dimethylbutyl) -N'-phenyl-p-phenylenediamine. Nevertheless, the properties of the resulting sealant change with it With the passage of time sufficient to give preference to quinoid and phenolic resin curing systems to make against vulcanization when sealing tires (pneumatic tires), if the sealant must withstand severe operating conditions over many years.

Chinoid hardenings are dependent on the crosslinking through the nitroso groups of aromatic nitroso compounds. In the quinone hearing system are p-quinone dioxime and p, p-dibenzoylquinone dioxime as more preferred. For examples of other suitable ones Harders include dibenzoyl-p-quinonedioxime, p-dinitrosobenzene, and N-methyl-N, 4-dinitrosoaniline the latter two clay-based compounds being called "Polyac" by the Company E.I. DuPont de Nemours & Co. or

are available as "Elastopar" from Monsanto Chemical Co.

To crosslinking activators which are used in the sealing agent according to the invention can be used include, for example, inorganic peroxides, organic peroxides (including diaroyl peroxides, diacyl peroxides and peroxyesters) and polysulfides. Suitable examples are lead peroxide, zinc peroxide, barium peroxide, copper peroxide, Potassium peroxide, silver peroxide, sodium peroxide, calcium poroxide; Mstallperoxyborate, -peroxychromates, -peroxyniobate, -peroxydicarbonote, peroxydiphosphate, -peroxydisulfate, -peroxygermanate, peroxymolybdate, -peroxynitrate, magnesium peroxide, Sodium pyrophosphate peroxide and the like; organic peroxides, such as lauryl peroxide, Benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, t-butyl peroxybenzoate, dibenzoyl peroxide, Bis (p-monomethoxybenzoyl) peroxide, p-monomethoxybenzoyl peroxide, bis (p-nitrobenzoyl) peroxide and phenacetyl peroxide; Metal polysulphides, such as calcium polysulphide, sodium polysulphide, Potassium polysulfide, barium polysulfide and the like, some organic sulfur-containing ones Compounds as described, for example, in US Pat. No. 2,619,481, and organic polysulfides of the general formula R- (S) -R, wherein R is a hydrocarbon group x and x represent a number from 2 to 4. It is believed that the 3 each crosslinking agent around the oxidation product of quinone dioxime, p-dinitrosobenzene acts.

The chinoid hardener / crosslinking activator combination as found which leads to the shortest gel time is the p-quinone dioxime / benzoyl peroxide combination. The preferred concentration of the p-quinone dioxide is 0.5 to 6 phr (parts by weight to 100 parts by weight). The preferred concentration of benzoyl peroxide is 1.5-18 phr (parts by weight per 100 parts by weight). If desired, accelerators can also be used be used. For example, cobolt naphthenot can be used in combination with t-butyl peroxibenzoate can be used and chioranil (2,3,5,6-tetrachloro-1,4-benzoquinone) can be used in combination can be used with t-butyl peroxy benzoate or benzoyl peroxide.

The phenolic resins used as hardeners according to the invention may include halomethylated alkylphenol resins, methylolphenol-formaldehyde resins and related species. Also suitable are bromomethylalkylphenol resins derived from Schenectady Chemicals, Inc. among the Trade name CRJ-328 and SP-1056 are available. The preferred concentration of the phenolic resin is 5 to 25 phr (parts by weight over 100 parts by weight). In the case of these resins, the use is activators not required.

The sealing means according to the invention contain one or more tackifying agents (tackifiers) which the sealant in the location on the tire (pneumatic tire) and on the object that pierces the tire to adhere and self-seal over the pierced hole afterwards the tire piercing object has been removed therefrom. In general, can any tackifying agent can be used that has a butyl rubber system is compatible (compatible). Such agents include polybutenes, polypropenes, paraffinic oils, petrolatum, phthalates and a number of resins including of polyterpenes, terpene phenolic resins, blocked phenolic resins, modified rosin and rosin esters and hydrocarbon resins. Preferred tackifiers are Polyisobutylenes and hydrocarbon resins and especially combinations thereof.

The sealing means according to the invention can be one or more disturbing Contain agents or fillers. In the case of sealants, made by a chinoid harness system have been heard, one of the amplifying agents must be finely divided carbon be. Carbon, such as carbon black, provides reaction centers for the quinoid hardening process and its content should be at least 2 parts by weight of the sealant, based on in each case 100 parts by weight of butyl rubber. Preferred soot concentrations are 30 to 60 phr (parts by weight to 100 parts by weight).

In the case of the substance that makes up the rest of the reinforcing agent, can either carbon black or any other suitable substance is selected based on the desired color of the sealant. at Sealing agents that have been cured by a phenolic resin hardener must be one the reinforcing agent can be at least 3 phr zinc oxide. The preferred concentration of zinc oxide is 5 to 30 phr. In sealants (compositions) that use Cured by phenolic resins, carbon black can also be used, its presence however, it is not required. Other known fortifying agents and fillers for butyl rubbers are e.g. aluminum hydrate, lithopon, whiting chalk, clays, hydrated Silicas, calcium silicates, silicooluminotes, magnesium oxide and magnesium carbonate.

To maintain sufficient tack and heat resistance The sealants of the present invention can assist at elevated temperatures also a thermoplastic and elastomeric partially hydrogenated block copolymer in an amount of up to about 10% by weight of the sealant, wherein dos block copolymers has the general formula A- (B-A) 1 5, wherein prior to the hydrogenation each A is a monovinylarene polymer block and each B is a conjugated Means diene polymer block. Typical examples of A monomers are styrene and α-methylstyrene and ring alkylated styrenes. Typical examples of B monomers are butadiene and Isoprene. The A blocks make up the end groups and they usually make up about 1/3 the weight of the copolymer and the B blocks form the middle groups and the remainder of the copolymer. The copolymer is partially hydrogenated, so that the conjugated diene block segments are essentially completely saturated. The monovinylarene polymer block segments are not noticeably saturated. The hydrogenation carried out in this way is improved the usefulness of the block copolymer as a component of the sealant, the like this to be resistant to oxidation and high temperature degradation. The average The molecular weight of the copolymer is within the range of about 60,000 to about 400,000 block copolymers of this type are in U.S. Patent 3,595,942.

The sealing means according to the invention are those which consist of the chemical components described above, whose tensile strength, Elongation and crosslink density have been adjusted (controlled) so that optimole Properties for tire sealants can be obtained. When it comes to tensile strength it is the stress per unit area of a sample of the sealant can withstand before it breaks (tears). The tensile strength in the one used here Sense is determined by first putting a sample of the sealant in the mold a thin plate (Felie) for 24 hours at room temperature, then another 24 Hours at 660C (1500F) and finally for 4 hours at 88 C (1900F).

Then hontelf-shaped using the ASTM "D" emboss Samples of the sealant cut out and the dimensions of the dumbbell-shaped Sample are determined. The sample is then placed in a conventional Dillon tensile tester inserted with jaws holding them by their wider end portions, and the sample is passed at a crosshead speed of 25.4 cm (10 inches) per minute stretched until it breaks. Tensile strength is the force at break divided by the original cross-sectional area of the narrow portion of the sample.

The elongation in the sense used here is determined according to a Procedure identical to that used for determining tensile strength. The stretch, Expressed in%, it is calculated by subtracting the original lung of the Sample from her lungs at break, multiply by 100, divide by the original Long and then, if necessary, multiply the result by one Correction factor, which compensates for the material, if necessary the end the jaws holding each end of the specimen has been withdrawn. The original Lungs and the ultimate fracture length obtained are determined by measuring the Clearances between the jaws. The sample is thus not only on the narrow, middle Section, but also stretched on part of the wider end sections of the specimen.

The crosslink density can be measured by performing a Swelling tests on a sample of the sealant using toluene as a solvent. As known to those skilled in the art, a swelling test provides a reliable and reproducible relative measure for the injury density. The swelling test is that which is absorbed by a given amount of crosslinked rubber The amount of solvent is measured and the test results are printed out as a swelling ratio between the weight of the solvent absorbed and the weight of the crosslinked Rubber (hereinafter referred to for the sake of simplicity as the "degree of swelling"). The greater the crosslink density of a given rubber sample, the lower is the freedom of the elastomeric network to expand by absorbing Solvent and the smaller is the degree of swelling (the swelling ratio). The test described here is carried out by weighing a sample of a dry (solvent-free) sealant, immersing the sample in toluene for one Period of 60 to 72 hours, removal and weighing of the wet sample and then Dry the sample for 30 minutes at 1490 ° C (300 ° F) and again To weigh. The weight of solvent absorbed is the wet weight minus the weight of the final dry weight.

Immersing the sample in toluene removes the constituents which have not been incorporated into the polymer network, which is insoluble in toluene, and the sample still contains the dipping and So dry essentially the crosslinked rubber and the carbon black or other fillers, if any available. In the event that the sealant contains a tackifier such as e.g. Functionally terminated polyisobutylene containing also remains part of the tackifier back in the network in the form of side chains. The amount of present in toluene insoluble materials can be calculated from the initial weight before Immerse the sample plus its known composition and these numbers can can be subtracted from the dry weight after immersion, the weight being of the crosslinked rubber is obtained.

The tests described above can be used by those skilled in the art Area can be easily done and the results of these tests can be used to manufacture of the sealing means according to the invention can be used. As stated above, the tensile strength of the sealant must be sufficiently high that the sealant through a typical perforation pool within the range of tire cuff prints, as they normally occur, is not "" blown through. It has been found that a reliable guide is that no more than 1.27 cm (1/2 inch) Sealant through a 0.52 cm (0.203 inch) diameter hole should be extruded at 3.25 bar (32 psig). The elongation must be sufficiently high so that the sealant is able to be applied to a piercing object to adhere without forming a cap, and is able to use a through-hole and to flow into it, after which the pierced object comes out of the tire has been removed. The crosslink density must be sufficiently high that the Sealant at elevated temperatures (e.g. up to 1040C (2200F)) does not flow or fatigue if a pierceable object is exposed during use of the Tire remains in this. The network density is allowed However not be so high that the sealant will form a cap if a transit object penetrates the tire. A reliable reference point for whether the elongation is sufficient high and the crosslink density is sufficiently low, is, as has been found, an 80% or greater "pass" score in the example below 1 static puncture test.

It has been found that preferred tire sealants contain those a tensile strength of at least about 2.11 kg / cm² (30 psi), an elongation of more than about 600% and degrees of swelling (swelling ratios) between about 12 and are about 40. Within these ranges, the sealing means according to the invention, has been found to have good tire sealing properties, both when that The object piercing the tire remains in the tire as well as when it is is removed, over the entire temperature range, the tire sealant normally exposed. In addition, sealing means according to the invention have proven themselves with elongations of more than 800% and swelling sizes (swelling ratios) within of the range from 12 to 35 as particularly suitable vehicle tire sealants proven and are therefore particularly preferred.

Sealants with tensile strengths, elongations and degrees of swelling (Swelling ratios) within these areas can thereby be produced (formulated) care must be taken that the compositions according to the invention (sealing agents) 13 to 40 weight percent butyl rubber having a molecular weight greater than about 100 000 and a mole percent unsaturation between about 0.5 and about 2.5 and by using at least 2 phr of carbon black and about 0.5 to about 6 phr of one Quinoid crosslinking agent. The rest of these compositions (sealants) consists of suitable tackifiers, Block copolymers, fillers Pigments and the like. Sealants with 13 to 20 fi Butylkoutschuk show how has been found to have short gel times and can easily after the spraying process are applied and they are therefore particularly preferred. Sealant with Tensile strengths, elongations and degrees of swelling (swelling ratios), as above indicated, can also be prepared (formulated) using 13 to 50% by weight butyl rubber having a molecular weight greater than about 100,000 and a mole percentage of unsaturation between about 0.5 and about 2.5, 5 to 25 phr a phenolic resin hardener and at least 3 phr zinc oxide with the remainder being the sealant consists of tackifiers and other modifiers.

The sealing means according to the invention can be applied in a wide variety of ways Way to be applied. They can be in the form of sprayable compositions which harden in situ, for example on the inner surface of a tire (pneumatic tire), or in the form of compositions that first form a plate (foil) cured and then applied. You can also click on one Substrate can be extruded or brushed on. During the manufacture of the sealant a solvent can be used. Suitable solvents include hexane, Toluene, heptane, naphtha, cyclohexanone, trichlorothylene, cyclohexane, methylene chloride, Chlorobenzene, ethylene dichloride, 1,1,1-trichloroethane and tetrahydrofuran and combinations of that.

Each specific sealant application process has limitations with respect to the composition of the sealant itself.

For example, if the sealant is solvated and direct is to be sprayed on a tire, it is appropriate to the amount of solvent used at a minimum (e.g. 35% or less) keep, so as to simplify solvent recovery processes and turnaround time To shorten. However, with solvent contents of 35% or less it was found that sealants of the invention that contain more than about 20% by weight butyl rubber no longer effective using an air-free process means can be sprayed on with a simple fixed nozzle. With air-free spray application therefore, sealants containing 20% or less butyl rubber are preferred. Sealants with more than 20% butyl rubber can be sprayed on with a nozzle that is moved back and forth over the tire tread (the tire tread).

A second processing limitation on the sealants of the invention is the curing time. The one required in a given sealant Bakeout time generally affects throughput, regardless of what is used Application process.

It has been found that sealing means according to the invention, which with less than about 2.0 phr of a quinoid crosslinking agent can be produced, gel times have that are unacceptably long for many uses. Sealant, that have been cured with greater than about 2.0 phr quinoid crosslinking agent, are therefore preferred. These sealants must of course also tensile, strength, Have elongation and crosslink density values as given above are. Since it has generally been found that sealing agents hardened with quinoid, which contain more than about 20 ff of butyl rubber do not have sufficient elongation properties if not less than about 2.0 phr of crosslinking agent are used, is the practical effect of being that preferred quinoid-hardened sealant are those containing no more than about 20 weight percent butyl rubber.

Because the sealing means according to the invention described here the have unique ability to be resistant to oxidation and over a wide range To remain stable and effective in the temperature range, they find numerous applications, for example as sealing mixtures and as roof sealing agents in addition to their Use a Is as a tire sealant (pneumatic tire sealant).

Because of the conditions a tire sealant is exposed to are the strictest, refer to the examples described below on sealants for these uses which the present invention should explain. It is clear that the relationship between the essential components can be varied within the above ongegebanen ranges and that the others Compounding materials (mixture materials) can be replaced and / or supplemented through other materials that are suitable for the requirements under consideration can.

Fig. 1 cer accompanying drawing shows with reference to a preferred embodiment of the vehicle tire sealing means is a vehicle tire 10, which is usually a tread section (tire profile) 12, a cork section 14 and side walls 16. It is generally in tubeless vehicle tires it is desirable to use a barrier or liner 18 that is impervious to air is. The air-impermeable lining 18 usually extends over the entire inner surface of the tire 10 from a rim contact portion 20 up to the other rim contact section 22. In the case of the one shown in FIG Embodiment of the invention is a sealant layer on the inside of the tire 10 against the air barrier layer 18.

The sealant layer 24 is arranged so that in principle lies behind the tread (the tire profile) 12 of the tire 10, so that the sealant layer in principle serves to drill holes in the Tread portion of the tire may occur to seal.

Fig. 2 illustrates another embodiment of the invention, at which has a vehicle tire 10 similar parts as in Fig. 1 with the same Reference numerals are denoted. In this particular embodiment, however, the sealant layer 24 between the carcass section 14 of the tire 10 and the barrier layer 18 impervious to air. The explained in Fig. 1 Vehicle tire embodiment normally occurs when the sealant layer 24 is applied after the tire 10 has been molded and cured. the In Fig. 2 Erlduterte Fohrzeugreifenaus implementation form occurs when the sealant layer 24 is incorporated into the tire 10 when the tire 10 is molded and cured will. The sealant layer can be used simultaneously with the manufacture of the vehicle tire are manufactured and hardened to achieve vert.ahrensök0naischer advantages, since the sealant layer can be located at temperatures of around 1770C (3500F) as applied when hearing the remaining rubber components of the tire will. When this is done it is possible to apply the sealant layer in a position as indicated by Figs. 1 and 2 to be arranged while when the sealant layer is applied after the tire is manufactured it is only possible to have such a layer within the impermeable to air Arrange barrier layer as shown in FIG. Finally, it should be noted that is, when the layer 24 covers the entire inner surface of the tire should, the air-impermeable barrier layer 18 from the vehicle tire construction can be completely omitted.

The sealing agent or sealant used in the following examples. Compositions were made by combining those in the following table I listed constituents (components) in the specified proportions, all of which are based on dry weight.

Table I Component A B .C D E F - G Butyl 1651) 15 - - 20 - 35 - 40 Butyl 3652) - 13 20 - 10 - - -Butyl 065 - - - - - - 40 -Vistanex4) 10 9.78 8.98 10 10 - - -H-1005) - 19.55 17.97 - 20 - -H-30065 23 - - 15 - 22 20 50 H-19007) 40 43 35.05 40 40 32 29 -Piccotac 8) 5 4.89 4.49 5 5 - - -zinc oxide - - - - - 10 10 10 carbon black 9 7 4.89 8.98 10 10 1 1 -Block Copolymer es 10) 4.89 4'.49 - 5 - - -p-quinone- 3.0 3.0 2.47 3.0 3.0 0.5 1.0 -dioxime Benzoyl-11) 11.0 9.0 7.41 9.0 9.0 1.5 3.0 -peroxide CJR-32811'12) - - - - - - 1p Footnotes to Table I 1) Butyl rubber having an isosity average molecular weight of 350,000 and a mole percentage the unsaturation (isopropene units / 100 monomer units) of 1.2 available from Exxon Oil Compan under the trademark "Butyl 165"; 2) butyl rubber having a viscosity average molecular weight of 350,000 and a mole percentage the unsaturation of 2.0, available from Exxon Oil Company under the trademark "Butyl 365"; 3) Butyl rubber having a viscosity average molecular weight of 350,000 and a mole percent in spite of unsaturation of 0.8 available from der Exxon Oil Company under the trademark "Butyl 065"; 45 polyisobutylene with a viscosity average molecular weight of 55,000 available from Exxon Oil Company under the trademark "Vistanex LM-MS"; 5) polybutene having an average molecular weight of 920 available from the company AMOCO under the trademark H-100 "; 6) polybutene with an average Molecular weight of 1290 available from AMOCO under the trademark "H-300"; 7) 2300 average molecular weight polybutene available from AMOCO under the trademark "H-1 900"; 8) hydrocarbon resin with a softening point of 970C, available from Hercules Inc. under the trademark "Piccotac B"; 9) Furnace soot with a surface area of 235 m² / g, an arithmetic mean diameter of 17 μm and a pH value of 6.0 to 9.0, available from Cities Service Oil Company under the trademark "Raven-2000"; 10) Block copolymer having the configuration A- (B-A) 1 5, wherein A is a Polystyrene block and B denotes a hydrogenated polyisoprene block, the isoprene about 2/3 the weight of the compound, and an average molecular weight between 70,000 and 150,000 available from Shell Oil Company under the Trademark "Kraton G-6500"; 11) parts to 100 parts of butyl rubber; 12) Dibromo-a'thy1octphenol having a number average molecular weight of 500 and a bromine content from 28 to 31%, available from Schenectady Chemicals, Inc. under the Trademark "CJR-328".

The invention is illustrated in more detail by the following examples, but without being limited to it.

Example 1 A tire sealant was prepared according to the prescription of the composition given above A.

The butyl rubber, the Vistanex and the Piccotac were made in hexane solvated and mixed so that the mixture contained about 50 weight percent solids. Then the carbon black and polybutenes were added to the previously solvated mixture. The p-quinone dioxime was then mixed in cyclohexanone to a dilution of about 40 weight percent solids, added to and dispersed in the mixture to form a first component that was about 73 weight percent solids. These The component was found to have a shelf life (shelf life) of longer than 6 months.

A second component was produced to perform a laboratory analysis by dissolving the benzoyl peroxide in toluene to a dilution of about 3 % Solids.

The first and the second component were then combined with each other, poured into molds and then at ambient temperature for 24 hours, then 24 hours cured (crosslinked) for 4 hours at 660C (1500F) and finally for 4 hours at 880C (1900F). Samples of the sealant were then tested to determine its tensile strength, Elongation and its degree of swelling. It has been found that the tensile strengths of this Sealant within the range of 2.46 to 3.16 kg / cm² (35 to AS psi), the elongations within the range of 967 to 998% and the degrees of swelling within of the range from 17.9 to 18.5 lay.

New ones were used to evaluate the sealant on a tire JR-78-15 steel belt radial tires used.

The tires were first made by brushing their inner surface with them cleaned with a wire brush and a soapy solution. The surfaces were then rinsed and dried.

A first component was produced as indicated above and a second component was made by dissolving the benzoyl peroxide in Methylene chloride so that the resulting solution was about 16% solids. The first component was then preheated to 127ob (2600F) with the second component combined to form a mixture having about 66% solids and below one Pressure of about 36.2 bar (500 psig) on the inner surface of a rotating Sprayed on tires.

The temperature of the first and second components after mixing was about 990C (2100F). 1200 g of sealant on a solvent-free Bases were sprayed onto each tire, the thickness being the one obtained Sealant layer under the central portion of the tread (of the tire tread) between 0.51 and 0.64 cm (0.2 to 0.25 inches) and at the tire shoulder at 0.38 com (0.15 inch). After spraying, the tires became continuous for about 10 minutes rotated until the sealant had hardened enough to be resistant to tiles to be. The tires were then removed from the applicator and Placed in an oven at 60 to 66 ° C (140 to 150 F) for 30 minutes.

The coated tires were subjected to a series of tests, around to assess the effectiveness of the sealant "on the tire". These tests included a puncture test, a static puncture test, and a dynamometer test. The blow-through test was carried out by drilling 6 holes in the hoop (two 0.36 cm (0.14 inch) in diameter, two with one 0.47 cm (0.187 inch) in diameter and two 0.52 cm in diameter (0.203 inch)) and plugging the holes with modulating clay prior to applying the sealant. After applying the sealant, the plugs were removed from the outside and the tire was inflated to 3.25 bar (32 psig) at ambient temperature, 3.95 bar (42 psig) psig) inflated at 820C (1800F) and 4.23 bar (46 psig) at 1040C (2200F). That Sealant was considered acceptable if less than about 1.27 cm (1/2 inch) sealant has been pushed through any hole and if none Air leakage from the tire has been detected.

The static piercing test (hole test) was performed on three different ones Temperatures performed: at -290C (-200F); at 2100 (700F); and at 820C (1800F). An 8 penny nail (0.29 cm in diameter (0.115 inch)) and a 20 penny nail (0.46 cm (0.180 inch) in diameter) in each outer tread groove and in two of the inner tread grooves of the tire tread drilled in. Each nail was stretched in two opposite directions for one minute Pivoted 45o, the nails were removed again and the hoop was at 3.25 inflated bar (32 psig) and tested for determination of a leak. The same procedures were then repeated, but this time the tire was in front inflated after being pierced. Air leaks at any point during of this test procedure were recorded.

The dynamometer test is probably the most popular test for that Performance of a tire sealant because it reflects actual driving conditions simulated. The test was carried out on a Celenkarm (pendulum arm) with a device for the rotatable fastening of a tire, with a movable contact device underneath the tire to make contact with the tire tread and to cause the tire to rotate, and a loading device for depressing it ir articulated arms (pendulum arms), so that the tire with a given force against the contact device was pressed. The test was performed under loads carried out that corresponded to 100% of the permitted tire loads. After this the tires coated with the sealant as indicated above and in Once attached to the dynamometer, they were inflated to 1.69 bar (24 psi) and for 2 hours at a rotation speed corresponding to 88.6 kg / hour. (55 mph). The pressure was then adjusted to 2.11 bar (30 psi) and as in the static puncture test, 8 nails were inserted, this time but 16 penny nails (0.37 cm (0.145 inch) diameter) instead of 20 penny nails were used. The tire was then again 16 100 km (10 000 miles) at a speed of 88.6 km / h. (55 mph) or allowed to run until the pressure dropped below 1.41 bar (20 psi), with at this time the responsible nail is determined, the nail pulled out and if necessary patched (sealed) and the test after the renewed Adjustment of the pressure to 2.11 bar (30 psi) was continued.

In the blow-through test, at ambient temperatures, one was negligible Amount of sealant pushed out at 820C (1800F) were average 0.32 cm (1/8 inch) pushed out and at 1040C (2200F) were average 1/4 inch (0.64 cm) pushed out. In no event did the tire lose a measurable amount Air.

These test results were good and they indicate that the sealant of composition A had sufficient tensile strength to be used as a vehicle tire sealant " means to function.

in the static puncture test, the sealant sealed removes an average of 89% of the perforations without significant air loss occurred. A detailed breakdown is given in Table II below: Table II Temperature - 290 C 21 ° C 820c (-200F) (70F) (1800F) nail diameter ( 0.115 inch (0.29 cm) 93% 97% 93% 0.180 inch (0.46 cm) 83% 9% 77% These Results show good puncture seal (hole seal) and they show further that the sealing agent has sufficient elongation and sufficient had low crosslink density, so that it was also on a penetrating object then adhered when the object was bent back and forth over an angle of 90 °.

In the dynamometer test, that traveled by a 16 penny nail average distance before a leak occurred, 6,601 km (4100 miles) and the average distance for an 8 penny nail was 13 685 km (8500 miles). These routes represent a considerable fraction of the service life (Service life) of an average tire. In addition, the dynomometer test represents as it was done here, conditions harsher than those like they occur in average driving since the test is 100% of the time for one Tire approved load has been carried out. This average route information therefore represent an excellent general sealing performance.

Example 2 Laboratory samples of composition A were like E example 1, but this time 4.5 phr p-quinone dioxime and 16.5 phr Benzoyl peroxide were used.

The sealant thus obtained had a tensile strength of 2.60 kg / cm2 (37 psi), an elongation of 804% and a degree of swelling of 16.2. the Increase in the amount of crosslinking agent increased the Crosslinking density (decrease in the degree of swelling), but the elongation also increased to the lower limit of the most preferred range.

Example 3 As in Example 1, tire sealants were both for the laboratory test as well as for the test on the tire according to the instructions given above of composition B produced. The hexane was replaced by toluene to reduce the To facilitate solvation of the block copolymer. The tensile strength, the elongation and the degree of swelling was found to be 2, 2.39 kg / cm2 (34 psi), 987 % and 17.83, respectively.

In the blow through test, 1.27 cm (0.5 inch) leaked at 820C during a leak occurred at 1040C (2200F). These results show that the tensile strength of the sealant was close to its lower preferred value. With the static one Puncture test an average of 98% of all perforations were sealed with success, indicating that the sealant has good elongation and crosslink density, which was not too high. On the dynamometer the average was Running distances for 16 and 8 penny nails 5152 km (3200 miles) or

9,660 km (6000 miles).

Example 4 As in Example 3, laboratory samples of the composition were made B. produced, but this time 5.0 phr p-quinone dioxime and 15.0 phr benzoyl peroxide were used. The tensile strength, elongation and degree of swelling were found to be 1.90 kg / cm2 (27 psi), 627% and 13.89, respectively. As in Example 2 it was made increasing the amount of crosslinking agent increases the crosslink density, the tensile strength and the elongation, however, simultaneously moved out of their preferred ranges. The low tensile strength of Composition B is generally proportionate to that a small amount of the butyl rubber present (13%). The examples 3 and 4 show that below this butyl rubber content it is difficult to obtain the Compensate for low rubber content by increasing the crosslinking agent while maintaining tensile strength and elongation within of the preferred areas.

Example 5 bs became a tire sealant for laboratory analysis prepared as in Example 3 according to the method of composition C given above. The tensile strength, elongation and degree of swelling were 5.0 kg / cm2 (71 psi), 538% and 12.71, respectively. These results show that the sealant is too inflexible was to give optimal performance in a vehicle tire, albeit under other less stringent conditions would work satisfactorily. The results also show that at the butyl rubber content of 20% using a Quinoid curing system A significant adjustment of the other factors is required to the properties of the sealant within their preferred ranges.

Example 6 Tire sealants were prepared as in Example 1, for the laboratory test as well as for the test on the tire according to the regulations of Composition D given above. Tensile strength, elongation and degree of swelling were found to be 4.71 kg / cm2 (67 psi), 6.70% and 11.86, respectively. The stretch was improved compared to Example 5, but the elongation was still outside the range of the most preferred range. It became a static puncture test performed with this sealant and the results are as follows Table III indicated with an average of 64% of the perforations with success were sealed.

Table III Temperature - 290C 2100 820C (-200F) (700F) (1800F) 0.29 cm nail diameter (0.115 inch) 53 2! ° 60% 87% 0.46 cm 60% 40% 87% (0.180 inch) As expected from the elongation test, this sealant had the least difficulty in sealing of through holes elevated temperatures.

Example 7 Laboratory samples of Composition D were made as in Example 6, but this time 2.0 phr p-quinone dioxime and 6.0 phr benzoyl peroxide were used. The thus obtained sealant had tensile strength of 4.76 kg / cm2 (68 psi), an elongation of 824% and a degree of swelling of 13.29. A decrease in the amount of crosslinking agent led, as expected, to an increase of the Grail of Swelling and also to an increase in elongation to a value within of the most preferred range.

This example shows that in general for quinoid hardened Composition with a comparatively larger amount of butyl rubber is a preferred one Sealing agent in many cases can be achieved by reducing the crosslink density, until sufficient elongation is achieved.

Example 8 It became a tire sealant for laboratory analysis prepared as in Example 3 according to the prescription of the composition given above E. The tensile strength, elongation and degree of swelling were found to be 0.98 kg / cm2 (14 psi), 754% and 17.69, respectively. The low tensile strength is in principle attributed to the small amount of butyl rubber (10 X0) present.

Example 9 Laboratory samples of composition E were made as in Example 8, but this time 5.0 phr p-quinone dioxime and 15.0 phr benzoyl peroxide were used. The thus obtained sealant had tensile strength of 1.12 kg / cm2 (16 psi) an elongation of 500% and a degree of swelling of 12.4. An increase in the amount of crosslinking agent led to a reduction in the degree of swelling, however, the tensile strength was far from being restored to a value within of the preferred range. The elongation also decreased. This example shows that it is difficult to find a preferred one using only 10% butyl rubber Manufacture tire sealants. Such sealing means can be used for others Purposes, for example, as a bicycle tire sealant, as sealing chemicals and the like. Can be used.

EXAMPLE 10 Good application of the formulation given above F became tire sealant for both laboratory analysis and analysis made on the tire.

The tensile strength, the elongation under the degree of swelling phr laboratory sample were found to be 3.59 kg / cm2 (51 psi), 1850% and 38.05, respectively. The results The dynamometer test showed an average running distance of 6,118 ka (3800 miles). Inspection of the tire, internal during the test revealed however, that the sealant had flowed.

Such flow was due to the comparatively low crosslink density of this sealant. Most preferred sealants are those with degrees of swelling from 12 to 35.

Example 11 As in Example 10, tire sealants were prepared, this time, however, 1.2 phr of p-quinone dioxime and 3.6 phr of benzoyl peroxide were used became. The tensile strength, elongation and degree of swelling of the sealant were 6.40 kg / cm² (91 psi), 986% and 16.68, respectively.

An increase in the amount of crosslinking agent resulted in a substantial one Increase in tensile strength and a decrease in the degree of swelling to a value within the preferred range. Dynamometer tests showed that this sealant did not flow. In general, the crosslinking density (for example the degree of swelling) more dependent (more sensitive) on that in the compositions, for example in the composition F, the amount of crosslinking agent present, the only small amounts Contains soot.

Examples 10 and 11 illustrate that a preferred tire sealant can be obtained using 35% butyl rubber and a quinoid curing system, when the amount of crosslinking agent and the amount of carbon black are greatly reduced. at However, p-quinone dioxime levels less than about 2.0 phr will increase the gel time of the sealant very long. This can be a critical factor in large-scale engineering Be spray application method, where the sprayed tires in the applicator must be held and rotated until the sealant is sufficiently gelled to permit handling without flowing. It was found, that a gel time of about 10 minutes at 660C (150OF) is a reasonable sealant application rate permitted. The gel times of the sealants of Examples 10 and 11 were at 66 C (1500F) 22 minutes and 12 minutes, respectively.

These times can be reduced by increasing the number used amount of p-quinone-dioxime, the consequence of which, however, as indicated in these examples, be that the elongation is reduced to a value outside the preferred range will.

Example 12 As in Example 1, tire sealants were both for laboratory analyzes as well as for analyzes carried out on the tire using the prescription for the above composition G. The tensile strength, the The elongation and degree of swelling of the laboratory samples were found to be 5.62 kg / cm2 (80 psi), 1197% and 17.54, respectively.

The dynamometer tests showed an average running distance of 4991 km (3100 miles) and there was no noticeable flow of the sealant on. This example, together with Example 11, shows that reducing the Mole percent unsaturation of the butyl rubber leads to an effect that opposed to increasing the amount of butyl rubber present and this can partially nullify.

Example 13 Similar to Example 1, tire sealants were used prepared for laboratory analysis using the procedure for the one given above Composition H. The first component was produced without the p-quinone dioxime and to make the second component, 6 parts by weight of CRJ-328 were used in 1 part by weight Toluene dispersed. The tensile strength, elongation and degree of swelling of the laboratory samples were found to be 3.94 kg / cm (56 psi), 1790% and 31.14, respectively. This example shows that preferred tire sealants utilize phenolic resin curing systems can be easily manufactured.

Example 14 As in Example 13, laboratory samples of the composition were made H produced 'but this time 20 phr CRJ-328 was used as hardener. The tensile strength, elongation and degree of swelling were 3.09 kg / cm2 (44 psi), 1191% and 18.07, respectively. As expected, when the amount of hardener was increased, the elongation increased and the degree of swelling, but their values were still within the preferred Areas.

Example 15 As in Example 14, laboratory samples of the composition were made H, but this time 10 phr CRJ-328 was used as hardener. The tensile strength, elongation and degree of swelling were 3.09 kg / cm2 (44 psi), 2875% or

35.71. By reducing the amount of hardener used, the elongation and the degree of swelling is increased to such an extent that the latter is no longer was within the most preferred range of 12.-35. The degree of swelling was less than 40, however this composition also worked as a vehicle tire sealant satisfactory.

While the invention has been more specifically preferred in the above Embodiments explained in more detail, but it should be noted that they by no means is limited to this, but that these are changed and modified in many ways without departing from the scope of the present invention will.

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Claims (17)

Sealing means, in particular for vehicle tires 1. Sealing means, in particular for vehicle tires, thereby g e k e n rr z e i c h n e t that it contains or consists of the reaction product of butyl rubber, which is only in the form of a copolymer having a viscosity average molecular weight of more than 100,000 is present, a hard (crosslinking agent) for butyl rubber and at least one tackifier compatible with butyl rubber, the a tensile strength of at least 2.11 kg / cm (30 psi), an elongation of at least 600% and has such a crosslinking density that its degree of swelling in toluene is between 12 and 40. 2. Sealing means according to claim 1, characterized in that it has an elongation of at least 800% and such a crosslink density, that its degree of swelling in toluene is between 12 and 35. 3. Sealing means still claim 1 and / or 2, characterized in that that the harder contains or consists of a quinoid crosslinking agent and a Crosslinking activator in an amount sufficient to cause a reaction between the Butyl rubber and the crosslinking agent to initiate, and that the sealant also contains at least 2 parts by weight of carbon black per 100 parts by weight of butyl rubber. 4. Sealing means according to at least one of claims 1 to 3, characterized in that the butyl rubber contains about 13 to about 40% by weight of the sealant made up exclusively of the crosslinking agent and the activator. 5. Sealing means according to at least one of claims 1 to 4, characterized in that the butyl rubber comprises 13 to 20% by weight of the sealant excluding the hard and that the carbon black in an amount of about 30 to about 60 parts by weight per 100 parts by weight of Butylkoutschuk is present. 6. Sealing means according to at least one of claims 1 to 5, there characterized in that the crosslinking agent in an amount between about 2 and about 6 parts by weight per 100 parts by weight of butyl rubber is present. 7. Sealing means according to at least one of claims 1 to 6, characterized in that the crosslinking agent contains or consists of p-quinone dioxime and that the crosslinking activator contains or consists of benzoyl peroxide, which in an amount between about 6 and about 18 parts by weight per 100 parts by weight of butyl rubber present0 8. Sealing means according to at least one of the claims 1 to 7, characterized in that the tackifier has a larger proportion of a polybutene and a minor portion of a hydrocarbon resin contains. 9. Sealing means or at least one of claims 1 to 8, characterized in that the hardener contains or consists of a phenolic resin, that in an amount between about 5 and about 25 parts by weight per 100 parts by weight of butyl rubber is present, and that the sealant also has at least 3 parts by weight of zinc oxide contains per 100 parts by weight of butyl rubber. 10. Sealing means according to at least one of claims 1 to 9, characterized in that it contains or consists of the reaction product of Butyl rubber, which is only available in the form of a copolymer with an average viscosity Molecular weight greater than 100,000 is a quinoid crosslinking agent, a crosslinking activator in an amount sufficient to cause a reaction between initiate the crosslinking agent and the butyl rubber, at least 2 parts by weight Carbon black per 100 parts by weight of rubber and at least one compatible with butyl rubber Sticky cup (compatible), the butyl rubber being 13 to 40% by weight of the sealant exclusively the crosslinking agent and the activator. 11. Sealing means according to claim 10, characterized in that the quinoid crosslinking agent in an amount between about 2 and about 6 parts by weight per 100 parts by weight of butyl rubber is present that the butyl rubber 13 to 20 wt .-% of the sealant makes up exclusively of the hardener and that the soot in one Amount between about 30 and about 60 parts by weight per 100 parts by weight of butyl rubber is present. 12. Sealing means according to claim 10 and / or 11, characterized in that that the degree of unsaturation of the butyl rubber is between about 0.5 and about 2.5 Mol%. 13. Sealing means according to at least one of claims 10 to 12, characterized in that the crosslinking agent contains or consists of p-quinone dioxime and that the crosslinking activator, which contains or consists of benzoyl peroxide, in an amount between about 6 and about 18 parts by weight per 100 parts by weight of butyl rubber is present. 14. Sealing means according to at least one of claims 1 to 13, characterized in that it contains or consists of the reaction product of Butyl rubber, which is only available in the form of a copolymer with an average viscosity Molecular weight of more than 100,000, a phenolic resin hearing aid, at least 3 parts by weight of zinc oxide to 100 parts by weight of butyl rubber and at least one with the butyl rubber compatible (compatible) sticky smear, whereby the butyl rubber 13 to 50% by weight of the sealant excluding the Herters. 15. Self-sealing tire, characterized by an annular Cover with a carcass section and sidewall sections and a layer from a sealing agent according to at least one of claims 1 to 14, the at least is applied to the carcass portion, the tensile strength, the elongation and the crosslink density of the on the inner surface of a tire in the form of a at least 0.38 cm (0.15 inch) thick layer of applied sealant so is that there is a hole up to 0.52 cm (0.203 inch) in size in a 3.25 bar (32 psig) bridged inflated tire at ambient temperature, using a nail 0.46 cm (0.18 inch) in diameter, which is the Tires and the The sealing layer penetrates so that the nail describes an arc of 90 °, sticks, the hole made by this nail both before and after pulling it out of the nail from the tire keeps hermetically sealed and at temperatures up to 1040C (2200F) under the forces experienced during normal tire use; maintains a non-flowing state. 16. A method of making a self-sealing tire, thereby characterized in that a) a sealant made of butyl rubber, which is only available in Form of a copolymer having a viscosity average molecular weight of more than 100,000 is present, a hardener for the butyl rubber and at least compounded with a tackifier compatible with butyl rubber and b) applying the sealant to the inner surface of the tire Formation of a partially cross-linked matrix with a tensile strength of at least 2.11 kg / cm² (30 psi), an elongation of at least 600% and such a crosslink density, that its degree of swelling in toluene is between 12 and 40. 17. The method according to claim 16, characterized in that the sealing means after application the product according to at least one of claims 1 to 14 results.