JPH10245452A - Low-permeable rubber laminate, and pneumatic tire and hose using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject laminate enabling a tire to have lighter weight, etc., without deteriorating the air pressure retaining property of a pneumatic tire, by dispersing a thermoplastic resin component as a flat oriented material in an elastomer matrix. SOLUTION: This laminate comprises (A) a thermoplastic resin component and (B) an elasmomer component, and is obtained by laminating a rubber composition containing the component A as a flat oriented material (preferably having >=10 ratio of the length to the thickness thereof) in a matrix having the volume fraction ϕP and the melt viscosity ηP when mixing the components A with B satisfying the formula α=(ϕR/ϕP)×(ηP/ηR)>1 (ϕR is the volume fraction of the component B; ηR is the melt viscosity of the component B at the temperature when kneading the components A with B under shear rate conditions) and the formula 0<β=ηP/ηR<1 onto another rubber layer. The pneumatic tire using the resultant laminate as air permeation preventing layer is capable of realizing lighter weight.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a laminate of a rubber composition having excellent air permeability and flexibility and another rubber layer, and a pneumatic tire and a low permeability hose using the same.

[0002]

2. Description of the Related Art Reduction of the fuel consumption rate is one of the major technical problems in automobiles, and as a measure against this, there is an increasing demand for lighter pneumatic tires. By the way, an inner liner layer made of rubber having low gas permeability such as butyl rubber is provided on the inner surface of the pneumatic tire in order to keep the tire air pressure constant. However, halogenated butyl rubber has a large hysteresis loss, so after vulcanization of the tire,
When the inner rubber of the carcass layer and the inner liner layer are corrugated in the gap between the carcass cords, the inner liner rubber layer is deformed together with the deformation of the carcass layer, so that the rolling resistance increases. Therefore, in general, the inner liner layer (halogenated butyl rubber) and the inner surface rubber of the carcass layer are joined to each other via a rubber sheet called a tie rubber having a small hysteresis loss. Therefore, in addition to the thickness of the inner liner layer of the halogenated butyl rubber, the thickness of the tie rubber is added, resulting in a thickness exceeding 1 mm (1000 μm) as a whole, which results in an increase in the weight of the product tire. Had become one.

A technique has been proposed in which various materials are used in place of a low gas permeable rubber such as butyl rubber as an inner liner layer of a pneumatic tire. For example,
In Japanese Patent No. 311761, the air permeability coefficient [cm ³ (standard state) / cm · sec · mmHg] is 30 × 10 ⁻¹³ or less at 30 ° C. and 50 × 10 ⁻¹³ or less at 70 ° C. of,
It is disclosed that a solution or dispersion of a synthetic resin such as polyvinylidene chloride, a saturated polyester resin, or a polyamide resin is applied to a thickness of 0.1 mm or less.

However, the technology disclosed in this publication is
On the inner peripheral surface of the carcass of the vulcanized tire, or on the inner peripheral surface of the inner liner, a coating layer of a synthetic resin having a specific air permeability coefficient is provided to reduce the thickness of the synthetic resin coating layer to 0.1 mm or less. However, the pneumatic tire described in this publication has a problem in adhesion between the rubber and the synthetic resin, and also has a drawback that the inner liner layer has poor moisture resistance (or water resistance).

Japanese Patent Application Laid-Open No. 5-330307 discloses that the inner surface of a tire is subjected to a halogenation treatment (using a conventionally known chlorination treatment solution, bromine solution and iodine solution), and methoxymethylated nylon, Polymer film of polymerized nylon, blend of polyurethane and polyvinylidene chloride, blend of polyurethane and polyvinylidene fluoride (film thickness 1
0-200 [mu] m).

Further, Japanese Patent Application Laid-Open No. 5-318618 discloses that
A pneumatic tire using a thin film of methoxymethylated nylon as an inner liner is disclosed. According to this technology, a solution or emulsion of methoxymethylated nylon is sprayed or applied to the inner surface of a green tire, and then the tire is vulcanized. Alternatively, a pneumatic tire is manufactured by spraying or applying a solution or emulsion of methoxymethylated nylon on the inner surface of the tire after vulcanization. However, the technique disclosed in this publication also has a disadvantage that it is difficult to maintain the uniformity of the film thickness in addition to the disadvantage that the thin film has poor water resistance.

Further, Japanese Patent Application Laid-Open No. 6-40207 discloses that
A non-air permeable layer made of a polyvinylidene chloride film or an ethylene vinyl alcohol copolymer film, and a multilayer film having an adhesive layer made of a polyolefin film, an aliphatic polyamide film, or a polyurethane film as an air permeation preventing layer of a tire. There is an example used. However, in this system, the non-air permeable layer lacks flexibility, and the film cannot follow the expansion and contraction of the material during running of the tire, and cracks may occur.

On the other hand, there is known a hose in which an inner tube, a reinforcing layer, and an outer tube are laminated in this order in a tubular shape. In particular, the inner tube and the outer tube are made of vulcanized rubber or resin, and the reinforcing layer is made of fiber, A steel wire such as steel or stainless steel or a steel wire plated with zinc or brass or the like is braided into a braid or spiral shape and subjected to an adhesive treatment such as rubberization as necessary. However, the so-called rubber hose using rubber for the inner and outer tubes requires a vulcanizing step, which complicates the manufacturing process. The resin hose using the thermoplastic resin for the inner and outer tubes is hard and inferior in flexibility.
At 0 ° C. or higher, there is a problem that heat resistance is inferior due to softening during heating. As a proposal for solving such a problem, a hose using a thermoplastic elastomer obtained by dispersing a vulcanized rubber in a thermoplastic resin such as a polyolefin resin, a polyvinyl chloride resin, a polyamide resin, or a polyester resin has been proposed. (See, for example, JP-A-6-64102). However, in recent years, for example, construction machinery has been aiming to reduce the size and weight and increase the output, and as a result, the temperature of the oil flowing through the hose for hydraulic piping has risen more and more, and it has become more heat-resistant and has been used for complicated piping. It is required to have flexibility that can be applied. At present, a typical structure of a hose for hydraulic piping is exemplified by a polyamide (or polyester) elastomer inner tube / reinforcement / urethane outer tube as an example. In this case, the urethane material used for the outer tube has a large decrease in physical properties when heated at 120 ° C., and there is a practical problem when used at a high temperature. In addition, polyamide (or polyester) elastomer, which is an inner tube material, has high rigidity because of its high rigidity, and has a problem that the hose is broken (kinked) and cannot be used for complicated piping.

Japanese Patent Application Laid-Open No. 60-186550 discloses that a vulcanizable rubber is used as a continuous phase, and a thermoplastic polymer having a CONH group is dispersed in a substantially spherical form in a vulcanizable rubber. It discloses a rubber composition suitable for applications such as vibration-proof rubber and packing in which both phases are chemically bonded via a novolak-type phenol resin. However, in the case of this rubber composition, since the dispersed thermoplastic polymer is spherical, it is inferior in the barrier property against air or gas, and is not sufficient for use in tires and hoses.

[0010]

As described above, various materials for the inner liner layer of a pneumatic tire have been proposed in place of butyl rubber, but have not yet been put to practical use. In particular, a material excellent in balance between air permeability resistance or gas permeability resistance and flexibility required for an inner liner layer or a hose of a pneumatic tire has not yet been developed.

[0011] Accordingly, an object of the present invention is to provide a tire that can be reduced in weight without impairing the air pressure retention of the pneumatic tire, and has an adhesive property with a rubber layer and an air permeation preventing layer for a pneumatic tire. Or a laminate of a rubber composition and another rubber layer optimal as an inner tube or outer tube of a hose, and a pneumatic tire using the same to form an air permeation preventing layer or a gas permeation preventing layer, and at least an outer tube or An object of the present invention is to provide a hose used for any of the inner tubes.

[0012]

According to the present invention, there is provided a rubber composition comprising a thermoplastic resin component and an elastomer component, wherein the thermoplastic resin component is dispersed as a flat oriented substance in an elastomer matrix. A laminated body obtained by laminating another rubber layer is provided.

According to the present invention, the thermoplastic resin component
A thermoplastic resin component and an elastomer.
Volume fraction φ when mixing with stoma component_pAnd melt viscosity
Degree η _pSatisfying the following expressions (I) and (II): α = (φ_R/ Φ_p) × (η_p/ Η_R)> 1 (I) 0 <β = η_p/ Η_R<1 ... (II) (where φ_R： Volume fraction of elastomer component φ_p: Volume fraction of thermoplastic resin component η_R: Temperature during kneading of thermoplastic resin component and elastomer component
Viscosity of Elastomer Components under Temperature and Shear Rate Conditions
Degree η_p: Temperature during kneading of thermoplastic resin component and elastomer component
Viscosity of Thermoplastic Resin Components at Degree and Shear Rate Conditions
Degree) The thermoplastic resin component is flat in the elastomer matrix
Rubber composition and other rubber layer dispersed as an oriented material
Are provided.

According to the present invention, the air permeability coefficient is 5
A pneumatic tire using the rubber composition having a Young's modulus of 1 to 500 MPa at 0 × 10 ⁻¹² cc · cm / cm ² · sec · cmHg or less as an air permeation preventing layer is provided.

According to the present invention, there is further provided a low permeability hose using the rubber composition for at least one of an inner tube and an outer tube of a hose having at least an inner tube, a reinforcing layer and an outer tube.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Examples of the thermoplastic resin constituting the rubber composition of the present invention include the following thermoplastic resins and mixtures of these or any resin containing them. Polyolefin resins (eg, high density polyethylene (HDPE), ultra high molecular weight polyethylene (UHMWPE), isotactic polypropylene,
Ethylene propylene copolymer resin), polyamide resin (for example, nylon 6 (N6), nylon 66 (N6
6), nylon 46 (N46), nylon 11 (N1
1), nylon 12 (N12), nylon 610 (N6
10), nylon 612 (N612), nylon 6/6
6 copolymer (N6 / 66), nylon 6/66/610
Copolymer (N6 / 66/610), nylon MXD6
(MXD6), nylon 6T, nylon 6 / 6T copolymer, nylon 66 / PP copolymer, nylon 66 / PP
S copolymer), polyester resin (for example, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyethylene isophthalate (PE)
I), PET / PEI copolymer, polyarylate (PA
R), polybutylene naphthalate (PBN), liquid crystal polyester, aromatic polyester such as polyoxyalkylenediimidic acid / polybutylate terephthalate copolymer), polynitrile resins (for example, polyacrylonitrile (PAN), polymethacrylonitrile, Acrylonitrile / styrene copolymer (AS), methacrylonitrile / styrene copolymer, methacrylonitrile / styrene /
Butadiene copolymer), polymethacrylate resin (eg, polymethyl methacrylate (PMMA), polyethyl methacrylate), polyvinyl resin (eg, vinyl acetate (EVA), polyvinyl alcohol (PVA), vinyl alcohol / ethylene copolymer (EVOH), polyvinylidene chloride (PVDC), polyvinyl chloride (PVC),
A vinyl chloride / vinylidene chloride copolymer, a vinylidene chloride / methyl acrylate copolymer), a cellulose resin (eg, cellulose acetate, cellulose acetate butyrate), a fluorine resin (eg, polyvinylidene fluoride (PVDF)),
Examples thereof include polyvinyl fluoride (PVF), polychlorofluoroethylene (PCTFE), tetrafluoroethylene / ethylene copolymer (ETFE), and imide-based resins (for example, aromatic polyimide (P1)).

The elastomer component constituting the rubber composition of the present invention may be, for example, the following elastomers or any of these or any mixture containing these as a main component. Diene rubbers and hydrogenated products thereof (eg, NR, IR, epoxidized natural rubber, SBR, BR (high cis BR and low cis BR), NBR, hydrogenated NBR, hydrogenated SBR), olefin rubbers (eg, ethylene propylene) Rubber (EPDM, EPM), maleic acid-modified ethylene propylene rubber (M-EPM), IIR, co-weight of isobutylene and aromatic vinyl or diene monomer, acrylic rubber (ACM), ionomer), halogen-containing rubber (for example, Br- IIR, CI-IIR, bromide of isobutylene paramethylstyrene copolymer (Br-IPM
S), CR, hydrin rubber (CHR), chlorosulfonated polyethylene (CSM), chlorinated polyethylene (C
M), maleic acid-modified chlorinated polyethylene (MC
M)), silicone rubber (eg, methyl vinyl silicone rubber, dimethyl silicone rubber, methyl phenyl vinyl silicone rubber), sulfur-containing rubber (eg, polysulfide rubber), fluorine rubber (eg, vinylidene fluoride rubber, fluorine-containing vinyl ether rubber, tetrafluoro Ethylene-propylene rubber, fluorine-containing silicon rubber,
Fluorinated phosphazene-based rubber) and thermoplastic elastomers (for example, styrene-based elastomer, olefin-based elastomer, ester-based elastomer, urethane-based elastomer, polyamide-based elastomer).

The ratio between the thermoplastic resin component and the elastomer component constituting the rubber composition according to the present invention is not particularly limited, but preferably the thermoplastic resin component: elastomer component = 90: 10 to 15: The criticality of this ratio depends on the volume ratio and the viscosity ratio of the thermoplastic resin component and the elastomer component. In the rubber composition used in the present invention, the elastomer component is used as a continuous phase, and even if both are simply kneaded in a molten state in order to form a thermoplastic resin component as a dispersion layer, the intended dispersion structure is not necessarily obtained. It is not possible to obtain a thermoplastic elastomer, and it is important to control the melt viscosity during kneading of the thermoplastic resin component and the elastomer component to be used for controlling the ratio of both components.

Here, the melt viscosity means an arbitrary temperature and a melt viscosity of a component during kneading, and the melt viscosity of each polymer material depends on temperature, shear rate (sec ^-1 ) and shear stress. Therefore, the stress and shear rate of the polymer material are generally measured at an arbitrary temperature in a molten state flowing in the thin tube, particularly at a temperature range during kneading, and the melt viscosity is measured by the following equation (2).

[0020]

(Equation 1)

The melt viscosity was measured using a capillary rheometer Capillograph 1C manufactured by Toyo Seiki Co., Ltd.

That is, in detail, in a mathematical expression that satisfies α = (φ _R / φ _p ) × (η _p / η _R ) (φ _p , φ _R , η _p and η _R are as defined above). As long as the value of α exceeds 1, any ratio may be used. The value of α is 1
When it is the following, the layer structure of the rubber composition of the present invention is reversed, and the thermoplastic resin component becomes a matrix, so that the rubber elasticity of the composition is excessively lost, and the material has poor heat resistance. It is because.

The viscosity ratio β (= η _P / η _R ) between the thermoplastic resin component and the elastomer component at the time of kneading is more than 0 and less than 1, preferably in the range of 0.1 to 0.9. This is because if the value of β is 1 or more, the thermoplastic resin component in the rubber composition is not sufficiently flattened, and cannot exhibit low permeability. Further, the ratio between the length and the thickness of the oriented material in the rubber composition needs to be 10 or more.
If it is less than 0, low permeability cannot be achieved.

The above-mentioned elastomer component or thermoplastic resin component contains a reinforcing agent, a filler, a softening agent, an antioxidant, etc. in order to improve the fluidity, heat resistance, physical strength, cost, etc. of the rubber composition. A necessary amount of a compounding agent usually added to the elastomer such as a processing aid can also be added.

When the specific thermoplastic resin component and the elastomer component have different chemical compatibility, it is preferable to use a suitable compatibilizer as the third component to make them compatible. By mixing the compatibilizer into the system, the interfacial tension between the thermoplastic resin component and the elastomer component decreases,
As a result, the elastomer (rubber) forming the dispersion layer
Since the particle diameter becomes fine, the characteristics of both components are more effectively expressed. Such a compatibilizer is generally a thermoplastic resin component, a copolymer having both or one structure of an elastomer component, or an epoxy group, a carboxyl group, a carbonyl group capable of reacting with the thermoplastic resin component or the elastomer component. , A copolymer having a halogen group, an amino group, an oxazoline group, a hydroxyl group and the like. These may be selected according to the types of the thermoplastic resin component and the elastomer component to be mixed, and those usually used include styrene-ethylene-butylene-styrene block copolymer (SEBS) and its maleic acid-modified product, EPDM, EPM and their maleic acid modified products, EPDM / styrene or EPDM /
An acrylonitrile graft copolymer and its maleic acid-modified product, a styrene / maleic acid copolymer, and a reactive phenoxine can be exemplified. The amount of the compatibilizer is not particularly limited, but is preferably 0.5 to 20 parts by weight based on 100 parts by weight of the polymer component (total of the thermoplastic resin and the elastomer).

The vulcanizing agent, vulcanization aid and vulcanization conditions (temperature, time) used for vulcanizing the elastomer component used in the rubber composition of the present invention depend on the composition of the elastomer component to be added. It may be determined appropriately and there is no particular limitation. As the vulcanizing agent, a general rubber vulcanizing agent (crosslinking agent) can be used. Specifically, examples of the sulfur-based vulcanizing agent include powdered sulfur, precipitated sulfur, highly dispersible sulfur, surface-treated sulfur, insoluble sulfur, dimorpholine disulfide, and alkylphenol disulfide. 4phr (Elastomer component (polymer) 1
About 100 parts by weight).

The organic peroxide-based vulcanizing agents include:
Benzoyl peroxide, t-butyl hydroperoxide, 2,4-dichlorobenzoyl peroxide,
Examples thereof include 2,5-dimethyl-2,5-di (t-butylperoxy) hexane and 2,5-dimethylhexane-2,5-di (peroxylbenzoate).
About 1 to 15 phr may be used. Further, examples of the phenol resin-based vulcanizing agent include brominated alkylphenol resins, and mixed cross-linking systems containing a halogen donor such as tin chloride and chlorobrene and an alkylphenol resin. Good.

In addition, zinc white (about 5 phr), magnesium oxide (about 4 phr), litharge (10 to 20 phr)
phr), p-quinonedioxime, p-dibenzoylquinonedioxime, tetrachloro-p-benzoquinone,
Poly-p-dinitrosobenzene (about 2 to 10 phr),
Methylene dianiline (about 0.2 to 10 phr) is exemplified.

[0029] If necessary, a vulcanization accelerator may be added. Examples of the vulcanization accelerator include general vulcanization accelerators such as aldehyde / ammonia, guanidine, thiazole, sulfenamide, thiuram, dithioate, and thiourea, for example, 0.5 to 2 phr. The degree may be used.

Specifically, the aldehyde / ammonia vulcanization accelerator includes hexamethylenetetramine and the like; the guanidine vulcanization accelerator includes diphenyl guandinine; and the thiazole vulcanization accelerator includes dibenzo. Thiazyl disulfide (DM), 2-mercaptobenzothiazole and its Zn salt, cyclohexylamine salt and the like; sulfenamide vulcanization accelerators include cyclohexylbenzothiazylsulfenamide (CBS);
N-oxydiethylenebenzothiazyl-2-sulfenamide, Nt-butyl-2-benzothiazolesulfenamide, 2- (thymolpolynyldithio) benzothiazole and the like; , Tetramethylthiuram disulfide (TMTD), tetraethylthiuram disulfide, tetramethylthiuram monosulfide (TMTM), dipentamethylenethiuram tetrasulfide, etc .; as dithioate vulcanization accelerators, Zn-dimethyldithiocarbamate; Zn-
Thiourea such as diethyldithiocarbamate, Zn-di-n-butyldithiocarbamate, Zn-ethylphenyldithiocarbamate, Tc-diethyldithiocarbamate, Cu-dimethyldithiocarbamate, Fe-dimethyldithiocarbamate, pipecoline pipecolyldithiocarbamate and the like; Examples of the vulcanization accelerator include ethylenethiourea, diethylthiourea and the like;
As a vulcanization accelerator, a general rubber auxiliary agent can be used in combination, for example, zinc white (about 5 phr),
Stearic acid and oleic acid and their Zn salts (2 to 2)
(About 4 phr) may be used.

The production of the rubber composition according to the present invention is carried out by, for example, using a banbury, an electric heating roll, an extruder for rubber, or the like, to melt the rubber, the resin, and, if necessary, the compatibilizer and the filler at the melting point of the thermoplastic resin or higher. The mixture is kneaded to orient and disperse the thermoplastic resin in a layer form in the elastomer matrix. The kneading shear rate at this time is preferably 50 to 1000 sec ^-1 . The higher the shear rate, the more easily the thermoplastic resin is oriented, resulting in increased low permeability of the rubber composition. Thereafter, the rubber composition is cooled with a cooling roll or the like in order to fix the orientation structure of the thermoplastic resin, and a vulcanization system is blended with the rubber composition and vulcanized according to a conventional method to obtain a desired vulcanized product. it can. During the vulcanization, the temperature must be lower than the melting point of the thermoplastic resin. If the vulcanization temperature exceeds the melting point of the resin, the thermoplastic resin oriented by applying shear stress melts and deforms into a spherical shape due to surface tension, so that the low permeability of the rubber composition is not achieved. It is because.

Hereinafter, a pneumatic tire having an air permeation preventing layer manufactured using the rubber composition of the present invention will be described. The air permeation prevention layer of the pneumatic tire according to the present invention can be arranged at an arbitrary position inside the tire, that is, inside or outside the carcass layer, or at another position.
In short, the object of the present invention is achieved by arranging the tire so as to prevent transmission and diffusion of air from the inside of the tire and maintain the air pressure inside the tire for a long period of time.

FIG. 1 is a half sectional view in the meridian direction illustrating a typical example of the arrangement of an air permeation preventing layer of a pneumatic tire. In FIG. 1, a carcass layer 2 is mounted between a pair of left and right bead cores 1, 1, and an inner liner layer 3 is provided on the inner surface of the tire inside the carcass layer 2. The inner liner layer 3 is composed of the polymer composition for a tire in the present invention. In FIG. 1, reference numeral 4 denotes a sidewall.

In the present invention, the method for producing the rubber composition constituting the air permeation preventing layer is as described above, and the condition for melt-kneading is that the temperature be at least the temperature at which the thermoplastic resin melts. The unvulcanized rubber composition which has been kneaded, cooled and charged with a vulcanizing agent by the above method is then formed into a sheet by roll forming extrusion or calendering. The method of forming a sheet may be a method of forming an ordinary rubber composition into a sheet. The thin film thus obtained has a structure in which a thermoplastic resin component is dispersed as a flat alignment material in a matrix of an elastomer component. By adopting such a structure, it is possible to impart both sufficient flexibility and sufficient low gas permeability to the sheet due to the effect of the resin layer as a flat barrier layer.

The method for manufacturing a pneumatic tire having an air permeation preventing layer formed of a thin film of the polymer composition according to the present invention is applied to a case where the inner liner layer 3 is disposed inside the carcass layer 2 as shown in FIG. To explain one example,
The rubber composition of the present invention is extruded into a thin film having a predetermined width and thickness in advance, and the thin film is adhered to a cylinder on a tire forming drum. The members used for normal tire production, such as a carcass layer, a belt layer, and a tread layer made of unvulcanized rubber, are sequentially laminated thereon, and the drum is pulled out to obtain a green tire. Next, by heating and vulcanizing the green tire according to a conventional method, a desired lightweight pneumatic tire can be manufactured.

The material of the rubber layer to which the air permeation preventing layer according to the present invention is adhered is not particularly limited, and may be any rubber material conventionally used as a rubber material for tires and the like. Examples of such rubbers include diene rubbers such as NR, IR, BR, and SBR, halogenated butyl rubbers, ethylene-propylene copolymer rubbers, styrene elastomers, and the like, which are mixed with carbon black, process oil, vulcanizing agents, and the like. It can be a rubber composition to which an agent has been added.

The air permeation preventing layer according to the present invention has an air permeability coefficient of 50 × 10 ⁻¹² cc · cm / cm ² · sec · cmHg or less.
It is preferably 10 × 10 ⁻¹² cc · cm / cm ² · sec · cmHg or less. Although there is no particular lower limit for the air permeability coefficient, it is practically 0.05 × 10 ⁻¹² cc · cm / cm ² · sec · cmHg.
Air permeation amount is 50 × 10 ^-12 cc · cm / cm ² · sec · cmHg
By setting the thickness below, the thickness of the air permeation preventing layer can be made smaller than the thickness of the conventional air permeation preventing layer, and as a result, the weight of the tire can be reduced.

On the other hand, the Young's modulus is 1 to 500 MPa, preferably 10 to 300 MPa, and the thickness is 0.2 to 1.0 mm, preferably 0.2 to 0.5 mm. If the Young's modulus is less than 1 MPa, handling becomes difficult due to wrinkles and the like during molding of the tire, which is not preferable. Conversely, if it is more than 500 MPa, the tire cannot follow the deformation of the tire during running.

The hose according to the present invention can be manufactured, for example, as follows. FIG. 2 shows a general hose structure having an inner tube, a reinforcing layer, and an outer tube. The rubber composition 6 for an inner tube of the present invention is extruded onto a mandrel 5 to which a release agent has been previously applied to form an inner tube. After that, if necessary, an adhesive 7 is applied or bonded in a sheet form or formed by a crosshead extruder for bonding with a reinforcing layer on the inner tube, and then a reinforcing yarn is formed by using a braiding machine. Alternatively, one or more layers of the reinforcing steel wire 8 are braided. An adhesive layer such as an adhesive may be provided between the reinforcing layers. After braiding, if necessary, an adhesive layer such as an adhesive 9 is formed for adhesion to the outer tube, and the outer tube composition 1 is formed thereon.
The rubber composition for an outer tube is extruded using a crosshead extruder suitable for the extrusion of No. 0 to form an outer tube. The hose can be manufactured by wrapping an iron cloth or the like on the unvulcanized hose structure, vulcanizing in a vulcanizing can, removing the wrapping tape after cooling, and pulling out the mandrel.

In the hose of the present invention, the reinforcing layer is
There is no particular limitation. Any of a blade-shaped member and a spiral-shaped member may be used. The material used may be a thread or a wire. As the reinforcing yarn, vinylon fiber, rayon fiber, polyester fiber,
Examples include yarns made of nylon fibers, aromatic polyamide fibers, and the like. More specifically, as the polyester fiber, as the polyester fiber, polyethylene terephthalate (manufactured by Toray Industries, Inc .: Tetron) is exemplified and generally used suitably. Examples of the nylon fiber include nylon 6, nylon 66 (manufactured by Asahi Kasei Corporation: Leona) and the like. Also, as the reinforcing wire, a hard steel wire is exemplified,
More specifically, a steel wire plated with brass, zinc, or the like for rust prevention and adhesion imparting is exemplified.

As the adhesive disposed on the inner tube and on the reinforcing layer or between the reinforcing layers, an incyanate-based adhesive, a phenolic resin-based, an epoxy resin-based, and a urethane-based adhesive can be used. Adhesives are preferred.
After the inner tube, the reinforcing layer, and the outer tube are formed in this manner, the mandrel is finally pulled out to obtain the hose of the present invention.

[0042]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but it goes without saying that the present invention is not limited to the following Examples. Examples 1 to 4 and Comparative Examples 1 and 2 (1) Preparation Method of Rubber Composition Various compounding agents are mixed with Cl-IIR and Br-IPMS, and master batches A and B are produced in a closed Banbury mixer. did. Table I shows the masterbatch formulation.

[0043]

[Table 1]

Next, the thermoplastic resin and the elastomer having the composition shown in Table II were charged into a Banbury mixer and mixed for 3 minutes, and released at a temperature higher than the melting point of the thermoplastic resin (in this case, the internal temperature of the Banbury mixer was 270 ° C.). Was removed, mixed with an electric heating roll at 250 ° C. for 5 minutes, and the thermoplastic resin was dispersed in a layer in the elastomer. Here, the shear rate of the electric heating roll was fixed at 300 sec ^-1 .
The material viscosity at a temperature of 250 ° C and a shear rate of 300 sec- ¹ is
It was measured with a capillary rheometer and is shown in Table II. Thereafter, the elastomer / thermoplastic resin mixture is heated to a set temperature of 50 ° C.
The vulcanization system was charged while cooling with a cooling roll of No. 5 and when it became sufficiently uniform, a 0.5 mm thick sheet was formed. The obtained sheet was vulcanized for 10 minutes at 180 ° C., which is lower than the melting point of the thermoplastic resin, and was subjected to the following evaluation. In Comparative Example 2, the masterbatch was directly transferred to a cooling roll at 50 ° C., and a vulcanization system was introduced, and a vulcanized sheet having a thickness of 0.5 mm was produced in the same manner as in the Example.

[0045]

[Table 2]

(2) Evaluation of Rubber Composition / Length / Thickness Ratio The above rubber composition was frozen, sliced using a microtome to prepare a sample, and the layer structure was observed with a transmission electron microscope. In the measurement, the length and thickness of the layered thermoplastic resin were measured at n = 10, and their average values are shown in Table II.

Young's modulus According to JIS K6251 “Method for tensile test of vulcanized rubber”. The samples prepared in each example were punched out with a JIS No. 3 dumbbell and subjected to a tensile test. A tangent was drawn on a curve in the initial strain region of the obtained stress-strain curve, and the Young's modulus was determined from the slope of the tangent. The results are shown in Table II.

Air permeability According to JIS K7126 "Testing method for gas permeability of plastic films and sheets (Method A)". The vulcanized rubber composition sheet sample prepared in each example was used as a test piece as it was. Test gas: Air (N ₂ : O ₂ = 8: 2) Test temperature: 30 ° C

Gas Permeability of Thermoplastic Elastomer Composition Material
Excess coefficient measurement method A stainless steel cup shown in FIG.
(CFC12 or HFC134a).
A sheet is placed on the upper part of the stainless steel cup for a test for measuring material properties, a sintered metal plate is placed on the sheet, and tightened with bolts and nuts. This is left in an atmosphere of 100 ° C., the total weight is measured every 24 hours, the decrease is calculated, and the gas permeability is calculated from the following equation. Gas permeability coefficient (mg · mm / 24h · cm ² ) = M · t / T ·
A, where A (cm ² ): Permeation area T (day): Time of test M (gf): Weight loss t (mm): Thickness of test piece

Example 5 A rubber composition having the composition shown in Table II was prepared and evaluated in the same manner as in the above example except that the temperature of the electric heating roll was changed to 270 ° C. The viscosity data was obtained by measuring the material viscosity at 270 ° C. and a shear rate of 300 sec ⁻¹ using a capillary rheometer. Table of results
See II.

Examples 6 and 7 The rubber compositions of Examples 1 and 3 were kneaded according to the above-mentioned preparation method to prepare an unvulcanized rubber sheet having a thickness of 0.3 mm. Next, the rubber composition sheet is wound around a tire molding drum, and a tire member is laminated thereon and inflated to obtain a green tire.
After vulcanization for 5 minutes, a tire having a tire size of 165SR13 was produced. A durability test and an air leak test were performed on the completed tire as follows. The results are shown in Table III.

[0052]

[Table 3]

Tire durability test method 165SR13 Steel radial tire (rim 13
× 4 1 / 2-J), with an air pressure of 140 kPa and a load of 5.5
Give kN and drive 10,000 km on the actual road. After running, remove the tire from the rim, visually observe the liner layer on the inner surface of the tire, cracks, cracks, visible wrinkles on the liner layer,
Those with peeling / lifting of the liner layer were judged as unacceptable (x), and those without were judged as acceptable (o). Table II shows the results
Shown in I.

Tire Air Leakage Performance Test Method 165SR13 Steel Radial Tire (Rim 13
× 4 1 / 2-J), the pressure was measured every four days at an initial pressure of 200 kPa under no load condition at room temperature of 21 ° C. for 3 months. As the measured pressure Pt, the initial pressure Po, and the number of elapsed days t, an α value is obtained by regressing on the function: Pt / Po = exp (−αt). Using the obtained α, t = 30
Is substituted into the following equation to obtain β = [1-exp (−αt)] × 100 β value. This β value is calculated as the pressure drop rate per month (% /
Month) and shown in Table III.

Comparative Example 3 In the case of using a butyl rubber having the composition shown in the following table as the inner liner layer instead of the rubber composition of the present invention, the characteristics as the inner liner and the characteristics of the finished tire were measured. The results are shown in Table III.

Combination of butyl inner liner @ Br-IIR ^{* 1} 100 Carbon black GPF ^{* 2} 60 Stearic acid 1 Petroleum hydrocarbon resin ^{* 3} 10 Paraffin-based process oil ^{* 4} 10 No. 3 zinc white 3 Accelerator 1 Sulfur 0.6 ──────────────────── * 1: Exon bromobutyl 2244 (Exxon Chemical * 2: Seast V (Tokai Carbon) * 3: Escolets 1102 (Esso Chemical) * 4: Machine oil (Showa Shell Sekiyu)

Examples 8 and 9 and Comparative Example 4 Preparation of Hose The rubber compositions of Examples 1 and 3 were kneaded according to the above-mentioned adjustment method, and then formed into a ribbon. Using this rubber composition and the Cl-IIR rubber composition (Comparative Example 4), an extruder having a crosshead structure was used. The tube was extruded onto the mandrel so that the inner thickness was 2 mm and 3 mm. Thereafter, a reinforcing fiber of polyester fiber (Tetron, 1500 d / 2, manufactured by Toray Industries Co., Ltd.) subjected to RFL dip treatment using a braiding machine is braided on the molded product,
A reinforcing layer was formed. Using a rubber extruder having a crosshead structure, the Cl-IIR rubber composition was extruded to a thickness of 1.5 mm on the reinforcing layer to form an outer tube. On this unvulcanized hose structure, it is wound up twice with a wrapping tape of nylon cloth.
Pressure vulcanization was performed at 3 ° C. × 60 minutes. After vulcanization, the wrapping tape was removed, and the mandrel was pulled out to obtain a hose.
Here, the blending of the Cl-IIR rubber composition used for the inner tube of Comparative Example 4 and the outer tubes of Examples 8, 9 and Comparative Example 4 is shown below.

Blended parts by weight of Cl-IIR rubber composition Bromine butyl rubber 100 Exxon bromobutyl 2244 Carbon black HAF 30 manufactured by Exxon Chemical Co., Ltd. ZnO 3 Zinc flower No. 3 manufactured by Tokai Carbon Co., Ltd. Place DM 1 Noxeller DM Ouchi Shinko Chemical Stearic acid 1 Beads stearic acid NY Nippon Yushi Co., Ltd. At this time, Chemlock 402 (Road Far East) was used as an adhesive between the layers. The hose thus manufactured was evaluated by the following method. Results are in Table IV
Shown in

[0059]

[Table 4]

Impulse test A test was conducted in accordance with SAE J188 type 1. (Oil: Auto multi oil (Idemitsu), 120 ° C) ○: At pressure of 210 kgf / cm ² , impulses of 1,000,000 times were given, and there were no abnormalities such as metal fittings missing or body breakage.

Gas Permeability Test JRA200 of JRA Standard (Japan Refrigeration and Air Conditioning Industry Association Standard)
Same as 1. A refrigerant (CFC12 or HFC134a) is sealed in a fitting assembly hose having a hose length of 0.45 m at 0.6 ± 0.1 gram per 1 cm ³ of the hose volume. It is left at a temperature of 100 ° C. for 96 hours, the weight loss (gas permeation amount) between 24 hours and 96 hours is measured, and the numerical value is converted to g / m / 72 hours.

Flexibility test The hose is bent along an arc having a predetermined radius, and the bending force is measured. The bending radius is 10 times the hose radius (10
The measurement is started from D), and the bending force is sequentially measured up to three times (n = 2). From the curve obtained by plotting the relationship between the bending force and the radius obtained as a result, the numerical value at a specified radius (4 times) is read. Generally, the flexibility of conventional rubber hose is 2.0
kgf level, and resin tube hose
Some are at the level of 6-7 kgf. In the case of a hose having such a resin tube structure, workability is clearly poor when the hose is attached to a device in a narrow space such as an engine room, and empirically, workability is good if the bending force is 3.5 kgf or less. , The softer, the better the workability. Weight The weight of the hose of Comparative Example 4 with the weight per meter per meter set to 100 is shown as a ratio.

[0063]

As described above, according to the present invention,
A laminate of a rubber composition and another rubber layer suitable for an air permeation prevention layer or a low permeability hose of a pneumatic tire, which has excellent air permeability and flexibility and can reduce the weight of tires and hoses. Can be obtained.

[Brief description of the drawings]

FIG. 1 is a half sectional view in the meridian direction showing a structure of an inner liner portion of a pneumatic tire of the present invention.

FIG. 2 is a view showing a general structure of a hose having an inner pipe, a reinforcing pipe, and an outer pipe according to the present invention.

FIG. 3 is a drawing showing an apparatus used for measuring a gas permeability coefficient of a thermoplastic elastomer composition material in Examples.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Bead core 2 ... Carcass layer 3 ... Inner liner layer 4 ... Side wall 5 ... Mandrel 6 ... Hose inner tube 7 ... Adhesive 8 ... Reinforcement layer 9 ... Adhesive 10 ... Hose outer tube 11 ... Cup 12 ... Freon gas 13 ... Sample Sheet 14 ... Sintered metal plate 15 ... Fixing member 16 ... Bolt 17 ... Nut

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tsuyoshi Kawaguchi 2-1 Oiwake, Hiratsuka-shi, Kanagawa Yokohama Rubber Co., Ltd. Inside the Hiratsuka Works (72) Inventor Yoshiaki Hashimura 2-1 Oiwake, Hiratsuka-shi, Kanagawa Yokohama Rubber Hiratsuka Factory

Claims (6)

[Claims] 1. A thermoplastic resin component and an elastomer component.
Comprising a thermoplastic resin component and an elastomer component.
Volume fraction φ when mixing_pAnd melt viscosity η _pIs
Α = (φ satisfying (I) and (II)_R/ Φ_p) × (η_p/ Η_R)> 1 (I) 0 <β = η_p/ Η_R<1 ... (II) (where φ_R： Volume fraction of elastomer component φ_p: Volume fraction of thermoplastic resin component η_R: Temperature during kneading of thermoplastic resin component and elastomer component
Viscosity of Elastomer Components under Temperature and Shear Rate Conditions
Degree η_p: Temperature during kneading of thermoplastic resin component and elastomer component
Viscosity of Thermoplastic Resin Components at Degree and Shear Rate Conditions
Degree) The thermoplastic resin component is flat in the elastomer matrix
Rubber composition and other rubber layer dispersed as an oriented material
A laminated body formed by laminating. 2. The rubber laminate according to claim 1, wherein the ratio between the length and the thickness of the flat polymer oriented product is 10 or more. 3. An air permeability coefficient of 50 × 10 ⁻¹² cc · cm /
3. A pneumatic tire using the rubber composition according to claim 1 or 2 as an air permeation preventing layer, having a Young's modulus of 1 to 500 MPa at or below cm ² · sec · cmHg. 4. The rubber composition according to claim 1, wherein the rubber composition is kneaded for phase determination at a temperature higher than the melting point of the thermoplastic resin, and the rubber composition is vulcanized at a temperature lower than the melting point. 3. The method for producing a pneumatic tire according to 3. 5. The rubber composition according to claim 1 or 2,
A low permeability hose used for at least one of an inner tube and an outer tube of a hose having at least an inner tube, a reinforcing layer, and an outer tube. 6. A rubber composition according to claim 1 or 2, which is kneaded for phase determination at a temperature higher than the melting point of the thermoplastic resin and vulcanized at a temperature lower than the melting point. 5. The method for producing a hose according to 5.