WO2016052986A1

WO2016052986A1 - Run-flat tire

Info

Publication number: WO2016052986A1
Application number: PCT/KR2015/010300
Authority: WO
Inventors: 정일; 최송연; 이상목
Original assignee: 코오롱인더스트리 주식회사
Priority date: 2014-09-30
Filing date: 2015-09-30
Publication date: 2016-04-07

Abstract

The present invention relates to a run-flat tire comprising, as an inner liner or inner reinforcing member, a polymer film which comprises: a copolymer including a polyamide-based segment and a poly-ether-based segment; and a polyamide-based resin, and which has a stress of 20 to 40Mpa when being extended by 25% at room temperature.

Description

[Explanation of invention]

[Name of invention]

Run Flat Tire

[Cross Citation with Related Application (s)]

The present application is the Korean Patent Application No. 10-2014-0131692 dated September 30, 2014 and

Claiming the benefit of priority based on Korean Patent Application No. 10-2015-0137395 dated September 30, 2015, all contents disclosed in the literature of the relevant Korean patent applications are incorporated as part of this specification.

Technical Field

The present invention relates to a run flat tire, and more particularly, it is possible to secure high tire shape stability and vehicle driving stability even when puncture occurs while minimizing tire thickness, weight, and increase, and improving strength, durability, and fatigue resistance. It relates to a run flat tire that can be implemented together.

[Technique to become background of invention]

The tires support the load of the vehicle, relieve the impact from the road surface, and transmit the driving force or braking force of the vehicle to the ground. Generally, the structure of a run flat tire protects the tread contacting the road surface and the carcass that forms the skeleton of the tire, the belt layer provided between the tread and the carcass, and the inner liner and carcass formed on the inner surface of the tire to prevent air leakage. It consists of a side wall and a bead to mount the tire on the rim to allow flexible flexing movement.

The run flat tire is mounted on the rim so as to surround the outer surface, and the air is layered on the inside of the tire to improve ride comfort and driving performance, and if the tire is punctured, the tire is loaded with a body load. Due to the flattening, the bead portion of the tire is in contact with the inner liner inside the tread can no longer drive.

In order to cope with such a state of inability to run, even if there is no air pressure inside the tire, the run-flat tire (Run-flat tire) that can drive a certain distance by supporting the load of the vehicle without flat tire has recently been Proposed. With such run flat tires, even if the air escapes from the inside of the tire due to an unexpected accident, the bead area may be applied to the inner liner inside the tread. Because it is not flat enough to contact, you can drive to the nearest repair shop without any trouble, and there is no need to carry a spare tire. Because of this, run flat tires are favored by drivers who drive long distances, drivers who cannot replace spare tires, especially women. There are various kinds of such run flat tires, for example, a change in the internal structure of the tire itself, and a separate member inserted into the tire. However, among these, inserting a separate member inside the tire has a problem that an increase in weight and a structure for mounting a separate member must be provided on the rim, and thus, a method of changing the internal structure of the tire itself is mainly used. It is used. This internal structure change method uses a lot of high-strength reinforcement rubber to increase the strength of the sidewall part, increases the weight of the tire and generates a lot of heat due to the repeated load due to the high-speed driving, especially near the bead Bending stress (shear stress) is generated in the separation of the body ply junction has a problem that often occurs.

In addition, in the case of changing the internal structure of the tire itself among the conventional run flat tires, although the end product is easy to mount, there is a disadvantage that the technical burden that the structural design of the tire itself or the like must be fundamentally changed.

Accordingly, the run flat tire can minimize the change of the internal structure of the tire and increase the weight of the tire, while the physical properties of the car are not degraded. Research on the development of dragon material is needed.

[Content of invention]

Problem to be solved

The present invention is to provide a run flat tire that can ensure high tire shape stability and vehicle running stability even when puncture occurs while minimizing the increase in the thickness or weight of the tire, and can be implemented with improved strength, durability and fatigue resistance characteristics. will be.

[Measures of problem]

In the present specification, a copolymer including a polyamide segment and a polyether segment; And polyamide-based resins, including at room temperature Provided is a run flat tire comprising a polymer film having a stress of 20 to 40 Mpa at 25% elongation as an innerliner or internal reinforcement.

Hereinafter, a run flat tire according to a specific embodiment of the present invention will be described in more detail. According to an embodiment of the present invention, a copolymer including a polyamide segment and a polyether segment; And a polyamide-based resin, and a run flat tire including a polymer film having a stress of 20 to 40 Mpa at 25% elongation at room temperature as an inner liner or an internal reinforcing material may be provided.

The present inventors include a copolymer comprising a polyamide segment and a polyether segment; And a polyamide-based resin, wherein a run flat tire using a polymer film having a stress of 20 to 40 Mpa at 25% elongation at room temperature as an inner liner or an internal reinforcing material may increase the thickness or weight of the tire. The experiment confirmed that high tire shape stability and automobile driving stability can be ensured even when puncture occurs, and that the improved strength, durability, and fatigue resistance can be realized together through experiments.

When the polymer film is used as an inner liner or internal reinforcement of the run flat tire, it may have a relatively low modulus with high durability, fatigue resistance and strength. More specifically, due to its specific composition and physical properties, the polymer film can significantly reduce the thickness or weight of the tire, compared to the case of using an inner liner or an internal reinforcement containing a component of a rubber system previously known, Compared with the components of the thermoplastic resins, high durability, fatigue resistance and strength can be ensured.

In addition, when the polymer film is used as an inner liner of the run flat tire, high airtightness resulting from the polyamide segment and the polyamide resin of the copolymer can be ensured, and the polyether (poly- Due to the properties originating from ether-based segments, it exhibits modest properties that are not very high compared to other polymer films.

That is, the run using the polymer film as an inner liner or internal reinforcing material Flat tires can suppress structural changes, thereby improving durability and stability against tire deformation, and ensuring high form stability and wear resistance due to high strength and moderate modulus, thereby enabling high-speed driving for a long time even during tire puncture.

When the polymer film is used as the internal reinforcing material, the internal reinforcing material may be used as a reinforcing material for any one or more of the shoulder portion and the side wall portion. Specifically, the part that is subjected to the highest load and pressure in the tire flattening is the shoulder portion and sidewall portion of the tire, in particular the sidewall portion serves to support the weight of the entire vehicle, the polymer film is the shoulder portion, sidewall portion Or as a reinforcement for all of them.

The internal reinforcing material may be located between the body fly portion and the inner liner portion in a cross section parallel to the width direction of the run flat tire. 3, the body fly portion and the inner liner portion in the cross section parallel to the width of the run flat tire are shown in FIG. 3.

Although the specific structure of the run flat tire is not limited to a large amount, for example, the run flat tire may include a tread portion; A pair of sled parts each connected to both sides about the tread part; A pair of sidewall portions continuous to each of the shoulder portions; A pair of bead portions continuous to each of the sidewall portions; A body fly portion formed inside the tread portion, the shoulder portion, the sidewall portion, and the bead portion; A belt portion and a cap fly portion sequentially stacked between the tread portion inner surface and the body fly portion; And it may include an inner liner coupled to the inside of the body fly.

Specifically, the run flat tire is a composite of fiber / steel / rubber, as shown in FIG. 1, a tread part, a body ply part, a belt t part, and a sidewall l. The liner may include an inner liner, a bead portion, and a cap ply portion.

The tread portion 1 is a portion in contact with the road surface, and provides a friction force necessary for braking and driving, and absorbs the outer layer space. The surface of the tread is formed with a certain groove (groove) can be expressed in the functions such as steering stability, traction, braking, drainage.

The shoulder portion 2 is continuous to both sides about the tread portion, respectively As a formed structure, it is located between both ends of a tread part and the upper end of a sidewall part. The side wall part 3 is a structure part connected to each of the shoulder parts, and refers to a rubber layer between the bead part 9 from the lower part of the shoulder part 2 and serves to protect the body fly part 6 therein. .

The bead part 9 is a structure part continuous to each of the sidewall parts, and serves to fix and fix the tire to the rim by Wi re Bundl e having a rubber-coated wire.

The body ply 6 (or carcass) is formed inside the tread portion, the sled portion, the sidewall portion and the bead portion, serves as a skeleton of the tire supporting the load of the vehicle body, and has a constant rubber component. It has a structure in which a tire cord is included inside. Specifically, the body ply includes at least 30% by weight of one or more rubber components selected from the group consisting of synthetic rubber and natural rubber, and may include one or more tire cords. As such a tire cord, various natural fibers or rayon, nylon, polyester, kevlar, or the like may be used, and a st ee l cord braided with a thin wire may also be used.

The belt portion 5 is located between the inner surface of the tread portion and the body fly portion, and in most cases is composed of a wire (Stee Lee Wi re), as well as to mitigate external impacts, as well as to the ground surface of the tread It keeps wide and secures driving stability.

The cap fly portion 4 is a special cord paper located between the inner surface of the belt portion and the body fly portion, and serves to minimize the movement of the belt during driving.

The inner liner ₇ is located inside the tire instead of the conventional tube, and serves to prevent air leakage.

The run flat tire may further include an APEX unit, which serves to minimize the dispersion of the beads and to mitigate external layer stratification to protect the beads and to prevent inflow of air during molding. It is generally a triangular rubber filler.

An example cross section of the run flat tire of the embodiment is as shown in FIG. 2. As shown in FIG. 2, the run flat tire of the embodiment includes a tread part 21, a body ply part 26, a belt part 25, A side wall (23) part, an inner liner (27), a bead (BEAD, 29) part, etc. may be included, and the above-mentioned polymer film may be included as an inner liner. Another example cross section of the run flat tire of the embodiment is as shown in FIG. 3. As shown in FIG. 3, the run flat tire according to the embodiment includes a tread part 31, a body ply part 36, a belt t part 35, and a side wall part 33. ), An inner liner 37, a bead 39, an internal reinforcement 30, and the like.

2 and 3 schematically show an example of the flat run tire of the embodiment, the details and specific examples thereof are not limited thereto.

As described above, when the polymer film is used as an internal reinforcing material, the internal reinforcing material may be used as a reinforcing material for any one or more of a shoulder part and a side wall part, and thus the internal reinforcing material is used among the shoulder part and side wall part. It may be formed over all or part of any one or more regions. "Formed over all or part of any one or more regions of said shoulder portion and sidewall portion" means a portion directly contacting or being projected to all or a portion of the shoulder portion, sidewall portion or both thereof (identified in the cross section of the tire, etc.) ) Means

When the polymer film is used as an inner liner, it may have a thickness of 50 to 300. When the polymer film is used as an inner liner, it exhibits airtightness of about 10 to 20 times compared to butyl rubber, which is generally used in tires, at the same thickness, and exhibits not much higher modulus properties than other resins. In addition, it has high strength, durability, and abrasion resistance, and can support a load of a vehicle only by remaining portions of the side walls at the time of tire puncture. When the polymer film is used as a reinforcing member ᅳ may have a thickness of 50 to 3,000. When the polymer film is used as a reinforcing member, the thickness of the film may vary depending on the same thickness or the location where the entire film is installed. In this case, the thickness of the polymer film is defined as the thickness of the thickest part of the entire region.

When the polymer film is used as a reinforcing member, the weight of the vehicle applied to the tire during puncture and the external pressure generated during driving may be properly absorbed and dispersed. Accordingly, the run flat tire of the embodiment ensures form stability and wear resistance to enable high speed driving for a long time even when the tire is punctured. The polymer film may also have a stress generated at a stretch of 25% of the polymer film at 60 ^° C., at least 10 Mpa.

Specifically, the polymer film may have a stress of 20% to 40 Mpa, preferably 22 to 38 Mpa at 25% elongation in phase silver in the first direction of the film, and may have a stress at 25% elongation at 60 ^° C. Stress may be 10 Mpa or more or 10 to 40 Mpa, preferably 12 Mpa or more.

Runflat tires are punctured at room temperature to support sidewalls, so the polymer film must have a modulus of 3-4 times greater than that of rubber modulus so that the runflat performance can be fully expressed. Stress at 25% elongation may be 20 Mpa. In addition, the run flat tires generate too high heat during normal operation. And a stress when the polymer film is 25% elongated at room temperature in order to prevent damage to the inner liner film by stress concentration, the stress may be 40 Mpa or less.

In addition, the polymer film may have a stress (Stress) of 10 Mpa or more at 25% elongation at 60 ^° C to fully express the run-flat performance. The 'first direction' means a plane perpendicular to the thickness direction of the polymer film, specifically, one direction defined on one surface of the polymer film, and for example, a longitudinal direction (MD; Machine Di rect) of the polymer film. ion), or the direction forming a predetermined angle with the longitudinal direction.

Meanwhile, the content of the polyether segment of the copolymer in the polymer film may be 2 to 40% by weight, 3 to 35% by weight, or 4 to ¾> to 30% by weight. When the content of the polyether repeating unit is less than 2% by weight of the polymer film, the modulus of the polymer film is increased, so that moldability may be lowered or physical property deterioration due to repetitive deformation may appear. Is high and the strain rate is low, it is difficult to mold the tire and the tire may be damaged due to lack of durability while driving the tire. On the other hand, if the polyether repeating unit content exceeds 40% by weight of the total polyamide-based elastomer composition, the pneumatic pressure retention performance is lowered and the sidewall support effect during puncture of the run-flat tire may be reduced. On the other hand, the polyamide-based segment included in the copolymer, nylon 6, nylon 66, nylon 46, nylon 11, nylon 12, nylon 610, nylon 612, nylon 6/66 copolymer, nylon 6/66/610 Copolymer, nylon MXD6, nylon 6T, nylon 6 / 6T copolymer, nylon 66 / PP copolymer, nylon 66 / PPS co-polymer, mesoxymethylated 6-nylon, methoxymethylated 6-610-nylon and It may be a main repeating unit included in one polyamide-based resin selected from the group consisting of 612-nylon methoxymethylate. For example, the main repeating unit of nylon 6 is ¾ in the formula (1) is known to be alkylene having 6 carbon atoms, the main repeating unit of other polyamide-based resin is also known to those skilled in the art. Specifically, the polyamide repeating unit may include a repeating unit represented by the following Chemical Formula 1 or Chemical Formula 2.

[Formula 1]

In Formula 1, ¾ is a linear or branched alkylene group having 1 to 20 carbon atoms, an arylene group having 6 to 20 carbon atoms, or a linear or branched arylalkylene group having 7 to 20 carbon atoms.

2]

In Chemical Formula 2, ¾ is a linear or branched alkylene group having 1 to 20 carbon atoms or an arylene group having 6 to 20 carbon atoms, and ¾ is a linear or branched alkylene group having 1 to 20 carbon atoms, and an aryl having 6 to 20 carbon atoms. Or a straight or branched arylalkylene group having 7 to 20 carbon atoms.

In the present specification, 'alkylene group ¹ ' refers to a divalent functional group derived from an alkyl group, and an 'arylalkylene group' refers to a divalent group derived from an alkyl group to which an aryl group is introduced. It means a functional group.

On the other hand, the polyether segment is an alkyl oxide (alkyl oxide, 'Akyl- It refers to a repeating unit containing a 0- ') group, it may be formed from a polyether resin or a precursor thereof to participate in the polymerization reaction.

The polyether-based segment may suppress the growth of large crystals in the polymer film or prevent the film from being easily broken during tire manufacturing or driving of an automobile. In addition, the polyether-based segment can lower the load generated during the modulus or stretching of the polymer film, so that even if a small force is applied when forming the tire can be stretched or deformed to fit the shape of the tire It is possible to easily mold the tire.

In addition, the polyether-based segment can suppress the increase in the rigidity of the film at low temperatures and prevent crystallization at high temperatures, and can prevent damage or tearing of the inner liner film due to repeated deformation. By improving the resilience to the deformation of the liner to suppress the occurrence of wrinkles of the film due to permanent deformation can improve the durability of the polymer film.

In the run flat tire, the polyether-based segment and the polyamide segment should have an appropriate content ratio for tire manufacturability, durability, and sidewall support in a run-flat situation.

The polyether segment may be a main repeating unit that may be included in a polyalkylene glycol resin or a derivative thereof. In this case, the polyalkylene glycol derivative may have an amine group, a carboxyl group or an isocyanate group at the terminal of the polyalkylene glycol resin. It may be a derivative substituted with, preferably substituted with an amine group. Preferably, the polyether segment is one selected from the group consisting of polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyoxyethylene diamine, polyoxypropylene diamine, polyoxytetramethylene diamine, and copolymers thereof. It may be a main repeating unit included in the polyether resin.

Specifically, the polyether segment may include a repeating unit of Formula 3 below.

[Formula 3]

In Formula 3, R ₅ may be a linear or branched alkylene group having 1 to 10 carbon atoms, n may be an integer of 1 to 100. In addition, the and R ₇ may be the same as or different from each other, and may be a direct bond, -0-, -NH-, -C00- or -C0NH-, respectively.

On the other hand, the above-mentioned copolymer is a polyamide (amide-based) and a poly-ether (polyether) segment from 8: 2 to 2: 8, or 7: 3 to 3: 7, or 6: 4 to 3 It may be included in a weight ratio of 7 :.

The increased average molecular weight of the co-polymer is 30,000 to 500,000, or 40, 000 to 300,000, or 50,000 to 200,000, or 60,000 to 150,000 days. Although the example of the method of measuring the weight average molecular weight of the said copolymer is not specifically limited, For example, the weight average molecular weight of polystyrene conversion measured by the GPC method can be used. In the process of measuring the weight average molecular weight of polystyrene conversion measured by the GPC method, a detector and an analytical column such as a conventionally known analytical device and a differential index detector (Refractive Index Detector) can be used, Conditions, solvents and flow rates can be applied. Specific examples of the above measurement conditions include silver ^at 30 ^° C., chloroform solvent, and a flow rate of 1 mL / min.

On the other hand, in order to improve the mechanical properties or airtightness of the polymer film may further comprise a polyamide-based resin. Such polyamide-based resin may be present on the film in a mixed state or a co-polymerized state with the copolymer of the polyamide-based segment and the polyether-based segment described above.

The polyamide-based resin may have a relative viscosity (96% solution of sulfuric acid) of 2.5 to 4.0, or 3.0 to 3.5. If the viscosity of the polyamide-based resin is less than 3.0, sufficient elongation may not be secured due to a decrease in toughness, which may cause damage during tire manufacturing or driving of a vehicle. It may be difficult to secure physical properties. In addition, when the viscosity of the polyamide-based resin exceeds 3.5, the modulus or viscosity of the inner liner film to be manufactured may be unnecessarily high, Tire innerliners may be difficult to have adequate formability or elasticity.

The relative viscosity of the polyamide-based resin refers to the relative viscosity measured using a 96% sulfuric acid solution at room temperature. Specifically, a sample of a certain polyamide-based resin (for example, 0.025 g of specimen) is dissolved in 96% sulfuric acid solution at different concentrations to prepare two or more measurement solutions (for example, a polyamide-based resin specimen). Dissolved in 97% sulfuric acid to make a concentration of 0.25 g / dL, 0.1 g / dL / 0.05 g / dL and prepared three measuring solutions), and the relative viscosity of the measuring solution using a viscosity tube at 25 ^° C. ( For example, the ratio of the average passage time of the measurement solution to the viscosity tube passage time of 96% sulfuric acid solution can be obtained.

Examples of the polyamide resin include polyamide resins such as nylon 6, nylon 66, nylon 46, nylon 11, nylon 12, nylon 610, nylon 612, and copolymers of nylon 6/66, nylon 6/66 / 610 copolymer, nylon MXD6, nylon 6T, nylon 6 / 6T copolymer, nylon 66 / PP copolymer and nylon 66 / PPS copolymer; Or their N-alkoxyalkylates, for example mesoxymethylates of 6-nylon, mesoxymethylates of 6-610-nylon or methoxymethylates of 612-nylon, nylon 6, nylon 66 nylon 46 , Nylon 11, nylon 12, nylon 610 or nylon 612 is preferred.

The polymer film is a polyamide-based resin and the copolymer from 8: 2 to

2: 8, or 7: 3 to 3: 7, or 6: 4 to 3: 7 by weight ratio. It may be included in the weight ratio of.

On the other hand, the polymer film may further include an olefin-based polymer compound. Specifically, the olefin-based polymer compound serves to increase the softness of the polymer film and to improve the ability to absorb the layer space applied from the outside, and also greatly reduce the modulus of the polymer film. The internal structure of the compound or polymer included in the compound can be changed to prevent the phenomenon of crystallization.

The polymer film is from 0.01% by weight of the olefin-based polymer compound

It may further comprise 30% by weight, or 1 to 25% by weight. If the content of the olefinic polymer compound is too small, the degree of action and effect according to the olefinic polymer compound may be insignificant. In addition, the content of the olefin-based high molecular compound Too large may reduce physical properties or effects expressed from the polyamide-based resin and the copolymer, and may be applied to the polymer film as an inner liner to reduce gas barier.

The olefin polymer compound may include an olefin polymer, an olefin copolymer, an olefin polymer or copolymer grafted with dicarboxylic acid or an acid anhydride thereof, or a mixture of two or more thereof.

The olefinic polymer may include polyethylene, polypropylene or a mixture thereof.

The olefinic copolymer may include an ethylene-propylene copolymer. As described above, the olefin-based high molecular compound may include an olefinic polymer or copolymer grafted with dicarboxylic acid or an acid anhydride thereof, and the dicarboxylic acid may be maleic acid, phthalic acid, itaconic acid or citraconic acid. , Alkenylsuccinic acid, cis-1,2,3,6 tetrahydrophthalic acid, 4-methyl-1,2,3,6 tetrahydrophthalic acid or a combination of two or more thereof, and the dicarboxyl The dianhydride of the acid may be the dicarboxylic dianhydride of the examples described above.

The content of the grafted dicarboxylic acid or acid anhydride thereof in the olefin-based polymer or copolymer grafted with dicarboxylic acid or acid anhydride thereof may be 0.05% by weight or more, and preferably from 0.01% by weight to 50 weight percent, or 0.5 weight percent to 10 weight percent.

The grafting ratio of such dicarboxylic acid or its acid anhydride can be measured from the result obtained by acid-base titrating the said olefin type high molecular compound. For example, about lg of the above-mentioned olefinic polymer compound was put in 150ii xylene saturated with water, and refluxed for about 2 hours. Then, a small amount of 1% by weight of thymol blue-dimethylformamide solution was added thereto, followed by 0.05 N sodium hydroxide-ethyl alcohol solution. After slightly titration to obtain a ultra-blue solution, the solution was again titrated until 0.05N hydrochloric acid-isopropyl alcohol solution showed yellow color, and the acid value was obtained. From this, the dicarboxyl grafted to the olefin polymer compound was obtained. The amount of acid can be calculated.

The olefinic polymer compound may have a density (Dens i ty) of 0.77g / citf to 0.95 g / cirf, or 0.80g / cirf to 0.93 g / cin ³ .

On the other hand, the run flat tire of the embodiment is at least one of the polymer film Is formed on one surface, may further comprise an adhesive layer comprising a resorcinol-formalin-latex (RFL) -based adhesive. The adhesive layer serves to fix the polymer film used as an inner liner or internal reinforcement to the run flat tire or its components.

The resorcinol-formalin-latex (RFL) -based adhesive is 2 to 32% by weight, preferably 10 to 20% by weight, and latex 68 to 98% by weight, preferably 80 to 80%, of a condensate of resorcinol and formaldehyde. And 90 weight percent. The condensate of resorcinol and formaldehyde may be obtained by mixing the resorcinol and formaldehyde in a molar ratio of 1: 0.3 to 1: 3.0, preferably 1: 0.5 to 1: 2.5, and then condensing the reaction. In addition, the condensate of resorcinol and formaldehyde may be included in more than 2% by weight relative to the total amount of the adhesive layer in terms of chemical reaction for excellent adhesion, and may be included in less than 32% by weight to ensure proper fatigue resistance properties. have.

The latex may be one or two or more combinations selected from the group consisting of natural rubber latex, styrene / butadiene rubber latex, acrylonitrile / butadiene rubber latex, chloroprene rubber latex and styrene / butadiene / vinylpyridine rubber latex. . The latex may be included in an amount of 68% by weight or more based on the total amount of the adhesive layer for flexibility of the material and effective crosslinking reaction with rubber. The latex may be included in an amount of 98% by weight or less for the chemical reaction with the polymer film and the rigidity of the adhesive layer.

The adhesive layer may have a thickness of 0.1 jm to 20, preferably 0.1 to 10 ai, more preferably 0.2 m to 7 urn, even more preferably 0.3 rn to 5, and the thickness of the polymer film It can be formed on one or both surfaces.

The run flat tire may further include a reinforcement layer using the polymer film as an inner liner and including a reinforcement rubber between the body ply part and the inner liner part. That is, the run flat tire may have a form in which the above-described polymer film is used as an inner liner and a member such as a high strength reinforcement rubber is inserted to increase the strength of the tire sidewall portion.

The production method of the run flat tire is, in the above-mentioned tire manufacturing laminate Except for removing and using the release film, the methods, conditions, and apparatus used in a typical run flat tire manufacturing process can be used without any particular limitation. 【Effects of the Invention]

According to the present invention, it is possible to secure high tire shape stability and vehicle driving stability even when puncture occurs while minimizing the increase in the thickness or weight of the tire, and provide a run flat tire that can realize improved strength, durability and fatigue resistance together. Can be.

[Brief Description of Drawings]

1 schematically shows the structure of a pneumatic tire.

2 is a half sectional view of a run flat tire according to one embodiment of the invention.

3 is a half sectional view of a run flat tire according to another embodiment of the invention.

[Specific contents to carry out invention]

The invention is explained in more detail in the following examples. However, the following examples are only for exemplifying the present invention, and the contents of the present invention are not limited to the following examples.

EXAMPLES AND PREPARATION EXAMPLES

Example 1 Manufacture of Film for Tire Inner Liner

(1) Manufacture of tire innerliner film

50 wt% of nylon 6 resin [relative viscosity (96% solution of sulfuric acid) 3.3], elastomer copolymer resin (50 wt% of polyamide segment ¾> and 50 wt% of polyether segment, absolute weight average molecular weight 150 50% by weight) was mixed first. It contains a heat-resistant agent [7% by weight of copper (Cu) in the mixture-complex of copper iodide and potassium iodide] and (1.0% by weight) ethylene-propylene copolymer (density 0.87 g / cirf) grafted with maleic anhydride Was added to prepare a mixture for producing a base film. The content of the heat-resistant agent in the mixture was 0.5% by weight, and the content of the olefin copolymer contained 15% by weight. After adjusting the temperature of the mixture to dry so that no chipping between the chips occurs, by controlling the temperature of the raw material supply portion was supplied to the extrusion die while preventing the complex from fusion from the extruder screw to feed failure. Then, the supplied mixture is extruded through a T-type die (die gap [Di e Gap] -1.0 kPa) at a temperature of 260 ^° C while maintaining a uniform melt flow and surface ^angle adjusted to 25 ^° C. An air knife (Ai r Knife) was used to cool and solidify the molten resin into a film of uniform thickness. Then, an unstretched film having a thickness of 100 was obtained without passing through the stretching and heat treatment sections at a speed of 15 m / min. The unstretched base film was aged for 24 hours at 25 ^° C. and 65% relative humidity conditions.

(2) application of adhesive

Resorcinol and formaldehyde were mixed at a molar ratio of 1: 2, and then condensed to form a condensate of resorcinol and formaldehyde. 12% by weight of the condensate of resorcinol and formaldehyde and 88% by weight of styrene / butadiene-1,3 / vinylpyridine latex were mixed to obtain a resorcinol-formalin-latex (RFL) adhesive bond having a concentration of 20%. . ^'

Then, the resorcinol-formalin-latex (RFL) -based adhesive was coated on the base film to a thickness of 1 surface using a gravure coater, dried and reacted at 150 ^° C. for 1 minute to form an adhesive layer. In order to adhere the adhesive to both sides of the base film, one side was treated under the above conditions, and then the other side was treated under the same conditions. In order to prevent the mutual adhesion of the base film when the other side of the adhesive treatment, a polyethylene terephthalate stretched film having a thickness of 12 was introduced into a release film, and wound like a base film to prepare an inner liner film coated on both sides.

The innerliner-based film thus prepared had a stress of 25 Mpa at 25% elongation at room temperature based on the MD direction, and had a modulus of 27 MPa at the yield point.

In addition, the stress at 25% elongation at 60 ^° C became 12 Mpa, and the oxygen permeability was measured by the American Material Testing Association ASTM D 3895, Oxygen Permeat ion Analyzer (Model 8000, manufactured by Ill inois Instruments). When measured under the condition of 25 ^° C. and 60 ^° C., 72 cc / (m ^! .24hr · atm) was obtained.

60% by weight of nylon 6 resin [relative viscosity (96% solution of sulfuric acid) 3.3], elastomer Similarly to Example 1 except that 40% by weight of copolymer resin (including 50% by weight of polyamide-based segment and 50% by weight of polyether-based segment, absolute weight average molecular weight 150, 000) was used for the tire inner liner. A film was prepared.

The inner liner base film thus prepared had a stress of 34 Mpa at 25% elongation at room temperature based on the MD direction, and had a modulus of 36 MPa at the yield point. ^In addition, the stress at 25% elongation at 60 ^° C became 13 Mpa. Oxygen permeability was measured using the Oxygen Permeat ion Analyzer (Model 8000, Ill inois Instruments, Inc.), in accordance with ASTM D 3895. ) Was measured ^at 25 ^° C, 60 ^° C atmosphere to represent 65 cc / dn '· 24hr · atm).

40 weight% of nylon 6 resin ^" [relative viscosity (96% solution of sulfuric acid) 3.3), and elastomeric copolymer resin (50 weight% of polyamide segment,> 50 weight% of polyether segment, absolute weight average molecular weight 150, 000) A film for tire innerliner was prepared in the same manner as in Example 1 except that 60% by weight was mixed.

The innerliner base film thus prepared had a stress of 22 Mpa at 25% elongation at room temperature based on the MD direction, and had a modulus of 23 MPa at the yield point.

In addition, the stress at 25% elongation at 60 degrees became 11 Mpa. Oxygen permeability was measured using the Oxygen Permeat ion Analyzer (Model 8000, manufactured by Ill inois Instruments) by the American Society for Testing and Materials, ASTM D 3895. 90 cc / (m ^! 24hr atm) when measured under 25 ^° C. and 60 ^° C. atmosphere. Production Examples 1 to 3: Production of Run Flat Tires

The run flat tire was manufactured using the film for tire innerliners obtained in the said Examples 1-3. At this time, the cord included in the body fly

1300De 72ply HMLS tires ^' cord is applied, and steel cord

Cord) and N66 840De '/ 2ply was applied as the cap ply.

Specifically, the prepared inner liner film on the tire forming drum In order to wrap and fix the inner liner film, the length of 3 cm was overlapped and the overlapped portion was fixed with a 1 mm thick tie gum. Then, a 2 隱 thick shoulder reinforcing rubber sheet (Sheet) was attached to a portion of the inner liner corresponding to the position where the crimp was to be formed with a width of 5 cm from 9 cm to 14 cm from the drum center.

And laminating the body fly rubber on the inner liner film, bead wire; Belt portion; Cap fly portion; And green tire was produced by sequentially forming a rubber layer for forming the tread portion sled portion and the side wall portion. The green tire thus prepared was put in a molding and subjected to a Curing step for 30 minutes at 160 ^° C. to produce a final run flat tire.

Comparative Example and Comparative Production Example

Comparative Example 1: Manufacture of Rubber Sheet for Tire Inner Liner

An inner liner rubber sheet was prepared by using a mixture of 50% halobutyl rubber, 20 wt% carbon block, 23 wt% Filer, and oil for the inner liner.

The rubber produced was made into a sheet of 1 mm by a rolling mill.

Comparative Example 2: Production of Film for Tire Inner Liner

90 weight% of nylon 6 resin [relative viscosity (96% solution of sulfuric acid) 3.3], and elastomer copolymer resin (50 weight% of polyamide segment and 50 weight% of polyether segment, absolute weight average molecular weight 150, 000) A film for tire innerliner was prepared in the same manner as in Example 1 except that 10% by weight was mixed.

The inner liner base film thus prepared had a stress of 51 Mpa at 25% elongation at room temperature based on the MD direction, and had a modulus of 55 MPa at the yield point.

In addition, the stress at 25% elongation at 60 ^° C became 17 Mpa. Oxygen permeability was measured according to ASTM D 3895, Oxygen Permeat ion Analyzer (Model 8000, manufactured by Ill inois Instruments). When measured under the condition of 25 ^° C. and 60 RH, the temperature was 31 cc / (m ² .24hr · atm). Comparative Example 3: Production of Film for Tire Inner Liner

Elastomer copolymer resin (including 50% by weight of polyamide segment and 50% by weight of polyether segment, absolute weight average molecular weight 150, 000) The film for tire innerliner was used in the same manner as in Example 1 Prepared.

The inner liner base film thus prepared was MD direction. As a guideline, the stress became 15 Mpa at 25% elongation at room temperature, and there was no yield point.

In addition, the stress at 25% elongation at 60 ^° C became 7 Mpa. Oxygen permeability was measured using the method of ASTM D 3895, Oxygen Permeat ion Analyzer (Model 8000, Ill inois Instrument s). When measured under the condition of 25 ^° C, 60 RH%, 350 cc / (m ² · 24hr. Atm) was obtained.

A run flat tire was manufactured using the tire innerliner film and rubber sheet obtained in Comparative Examples 1 to 3. At this time, 1300De 72ply HMLS tire cord was applied as body cord, steel cord was used as belt, and N66 840De '/ 2ply product was used as cap fly.

Specifically, the prepared inner liner film was wrapped on a tire forming drum, and in order to fix the inner liner film, a length of 3 cm was overlapped and the overlapped portion was fixed with a 1 의 thick tie gum. Then, a 2 mm thick sled reinforcement rubber sheet (Sheet) was attached to a portion of the inner liner corresponding to the position where the crimp was to be formed with a width of 5 cm from 9 cm to 14 cm from the center of the drum.

And, laminating the body fly rubber on the inner liner film, bead wire; Belt portion; Cap fly portion; And a rubber layer for sequentially forming the tread part, the shoulder part and the side wall part to manufacture the green tire. The green tire thus prepared was put in a molding and subjected to a Curing step for 30 minutes at 160 ^° C. to produce a final run flat tire.

Experimental Example: Measurement of Properties of Run Flat Tires (1) durability measurement

The tire durability measurement method was used to evaluate the tire durability while increasing the load. This durability measurement was carried out in two ways, the endurance test to increase the load by the step load method and the high speed test to increase the speed, Examples 1 to 5 and Comparative Examples 2 to 3 with the result of Comparative Example 1 as 100 The results were compared and evaluated.

(2) Air pressure holding performance measurement

Tires prepared by applying the tire inner liner films of the above Examples and Comparative Examples were compared by measuring the IPR Internal Pressure Retent ion for 90 days at 101.3 kPa pressure at 21 ^° C. using ASTM F1112-06 method. Evaluated.

At this time, it can be recognized that the case where the IPR value is high is a high air retention.

(3) tire manufacturing processability

In a tire manufactured by applying the tire inner liner films of the above Examples and Comparative Examples, the tire manufacturing processability was evaluated by identifying whether a defect such as film tearing or cracking occurred in the tire after tire production.

100 tires were manufactured by applying the tire inner liner films of the above examples and comparative examples, and the number of normal products without any internal defects such as film tearing or cracking was measured by visually observing the inside of the manufactured tires. The yield of the normal product is shown as tire manufacturing processability.

(4) Flat state driving performance

The center of the tread of the tire was pierced through a 3 mm diameter awl to reduce the air pressure. Then, the distance traveled under the tire design load condition under the speed of 80 km using the tire durability measurement method. The results of the evaluation of run flat tire physical properties to which the base film for tire innerliner manufactured by the above Examples and Comparative Examples are applied are shown in Table 1 below.

Table 1

Durability Measurement 105 103 108 100 95

Endurance Test (%)

Durability Measurement 105 104 105 100 103

High Speed Test (%)

Pneumatic holding performance (IPR) 98.5 98.8 98.3 97 87

[% / 3month]

Flat state driving performance (km) 140 145 130 120 125 Tire manufacturing processability (%) Good Good Good Good Good As the above, the inner liner film of Examples 1 to 3 according to the present invention is excellent in the application of run flat tires. It can be seen that the gas barrier can support a certain amount of load even in an accident such as a puncture, and can travel a certain distance, and ensure excellent durability and fatigue resistance even in a tire manufacturing process or a vehicle driving process.

[Explanation of code]

1 ： Tread part

2: shoulder

3 ： Side wall part

4: cap fly part

5: Belt part

6: body fly (or carcass)

7: Inner Liner

8 ： APEX

9: bead part

21 ： Tread part

23 ： Sidewall

25 ： Belt part

26 ： Body fly part

27 ： Inner Liner

29 ： Bead

30: internal reinforcement ： Tread part ： Sidewall ： mi ᄐ

S― ： Body fly part: Inner liner ： Bead

Claims

【Claims】

【Claim 1】

A copolymer comprising a polyamide-based segment and a polyether-based segment; and a polyamide-based resin; and a run-flat tire comprising, as an inner liner or internal reinforcement, a polymer film having a stress of 20 to 40 MPa when stretched 25% at room temperature.

【Claim 2】

In clause 1,

The internal reinforcing material is a reinforcing material for one or more of the shoulder portion and the side wall portion, a run-flat tire.

[Claim 3]

In paragraph 2,

The internal reinforcement is a run-flat tire located between the body ply portion and the inner liner portion in a cross-section parallel to the width direction of the run-flat tire.

[Claim 4]

In clause 1,

The run flat tire includes a tread portion; a pair of continuous shoulder parts on both sides centered on the tread part; A pair of side wall portions continuous to each of the shoulder portions; A pair of continuous bead portions on each side wall portion; A body ^ply portion formed inside the tread portion, sled portion, side wall portion, and bead portion; a belt portion and a cap ply portion sequentially stacked between the inner surface of the tread portion and the body ply portion; And a run-flat tire comprising an inner liner coupled to the inside of the body ply portion.

【Claim 5】

In clause 4,

The internal reinforcement is formed over all or part of one or more of the slender portion and the sidewall portion. A run-flat tire.

【Claim 6】

In clause 1,

The polymer film is an inner liner having a thickness of 50 to 300, a run flat tire.

【Claim 7】

In clause 1,

The polymer film is an internal reinforcing material having a thickness of 50 to 3,000 庫, a run-flat tire.

[Claim 8]

In clause 1,

A run-flat tire in which the stress generated when the polymer film is stretched by 25% at 60 ^° C is 10 Mpa or more.

【Claim 9】

In clause 1,

A run-flat tire, wherein the content of the polyether-based segment of the copolymer in the polymer film is 2 to 40% by weight.

【Claim 10】

In clause 1,

The polyamide-based repeating unit is a run-flat tire comprising a repeating unit represented by the following Formula 1 or Formula 2:

[Formula 1]

In Formula 1, Ri is a straight or branched chain having 1 to 20 carbon atoms. The alkylene group is an arylene group having 6 to 20 carbon atoms, or a straight-chain or branched arylalkylene group having 7 to 20 carbon atoms,

[Formula 2]

0 0

丄 II II H H

-ᅳ Cᅳ R ₂ — C 1 N 1 Rs 1 N1 ᅳ 1 In Formula 2, R ₂ is a straight-chain or branched alkylene group with 1 to 20 carbon atoms or an arylene group with 6 to 20 carbon atoms, and ¾ is 1 carbon atom. It is a straight-chain or branched alkylene group with 20 to 20 carbon atoms, an arylene group with 6 to 20 carbon atoms, or a straight-chain or branched arylalkylene group with 7 to 20 carbon atoms.

【Claim 11】

In paragraph 1,

The polyether-based repeating unit is a run-flat tire comprising a repeating unit represented by the following formula (3):

3]

In Formula 3 above,

R ₅ is a straight or branched alkylene group having 1 to 10 carbon atoms, n is an integer from 1 to 100,

R ₆ and R ₇ may be the same or different from each other, and are each a direct bond -0-, -NH-, -C00-, or -C0NH-.

[Claim 12]

In clause 1,

The copolymer included in the polymer film includes polyamide-based segments and polyether-based segments at a weight ratio of 8:2 to 2:8.

[Claim 13]

In paragraph 1,

The polyamide-based resin is a run-flat tire having a relative viscosity of 2.5 to 4.0 (96% sulfuric acid solution).

【Claim 14】

According to clause 1,

The polymer film is a run-flat tire comprising a polyamide-based resin and the copolymer at an increase ratio of 8:2 to 2:8.

【Claim 15】

In paragraph 1, .

A run-flat tire wherein the polymer film further includes an olefin-based polymer compound.

【Claim 16】

In clause 15,

The olefin-based polymer compound is a run flat tire containing one or more compounds selected from the group consisting of olefin-based polymers, olefin-based copolymers, and olefin-based polymers or copolymers grafted with dicarboxylic acid or an acid anhydride thereof. .

【Claim 17】

^' In clause 15,

The polymer film contains 0.1% by weight of the olefin-based polymer compound.

Run-flat tires, including 30 weight ¾.

【Claim 18】

In clause 1,

Formed on at least one side of the polymer film and resorcinol—formalin— A run flat tire further comprising an adhesive layer containing a latex (RFL)-based adhesive.

【Claim 19】

According to clause 18,

A run flat tire wherein the adhesive layer has a thickness of 0.1 to 20 zm.

【Claim 20】

According to clause 12,

The polymer film is included as an inner liner,

A run-flat tire including a reinforcing layer containing reinforcing rubber between the body ply portion and the inner liner portion.