JP4978646B2 - Pneumatic tire manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a pneumatic tire preventing generation of a defect coming from an air trap by effectively dispersing trapped air between a resin-compounded inner liner layer member and an unvulcanized tire body. <P>SOLUTION: The manufacturing method of the pneumatic tire includes: compounding an unvulcanized tire body having the carcass layer 4 on the tire inner surface and a thermoplastic resin; laminating a resin-compounded inner liner layer to be laminated on the inner surface of a carcass layer 4, to form a rubber composite material; and pressing and heating the rubber composite material to form a pneumatic tire. The surface of the resin-compounded inner liner layer on the lamination side has an uneven surface composed of a protrusive part in contact with the unvulcanized tire body and a recessed part out of contact with the same, the recessed part extends in a mesh-like shape, the whole contact surface area of the protrusive part is not less than 25% and not more than 99% of the whole surface area the protrusive part contacts, and the recessed part works as an air escape portion enabling the trapped air between the unvulcanized tire body and the resin-compounded inner liner layer member to move and disperse between the layers. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a method for producing a pneumatic tire, and more particularly, a resin-blended inner liner in which an unvulcanized tire body having a carcass layer on the tire inner surface and a thermoplastic resin are blended and laminated on the inner surface of the carcass layer. In a pneumatic tire manufacturing method in which a rubber composite material formed by laminating layers is molded and the rubber composite material is pressurized and heated to manufacture a pneumatic tire, so as to prevent occurrence of defects due to air accumulation between the stacked layers The present invention relates to a method for manufacturing a pneumatic tire.

  In recent years, pneumatic tires are strongly demanded to be lighter in order to improve the fuel efficiency of vehicles. Therefore, for example, a technology has been proposed in which a film-like resin compounding member (resin compounding inner liner layer) in which a thermoplastic resin is compounded is used for an inner liner layer made of rubber, which has been used as an air permeation prevention layer. Has been. By blending a resin with low air permeability compared to rubber and using an inner liner layer member that is thinner than an inner liner layer made of conventional rubber, the weight of the pneumatic tire is reduced. .

  However, a green tire molded using a resin-blended inner liner layer and having a large amount of air sandwiched between the resin-blended inner liner layer and a tire component (unvulcanized tire body) at the time of tire molding When vulcanized and the amount of air exceeds the amount absorbed or permeated by the surrounding members during vulcanization, the air remains as a relatively high-pressure gas around the members, and the inside of the tire in the final vulcanization stage The internal pressure of the molding bladder that is pressurized from the pressure is reduced and contracted, and when the tire surface is released to atmospheric pressure, the strength at high temperature is lower than that of rubber, so the resin-blended inner liner member expands the gas between the members There was a problem that it could not withstand the force and protruded greatly to the outside. Therefore, conventionally, as a countermeasure, when laminating the resin-blended inner liner member and the unvulcanized tire body, the pressure is sequentially pressed from the end with a roller so that the air is not confined as much as possible from the beginning. There is a method of substantially reducing the amount of air between layers to a limit amount or less that can be absorbed or permeated by surrounding members.

  However, this method alone cannot exhaust the air sufficiently, or the air collected by crimping with a roller accumulates locally due to steps, minute dents, tightness of adhesion, etc. By tightly adhering, air is enclosed, and during vulcanization, the air cannot move and disperse to the periphery, so the amount that can be absorbed and permeated by surrounding members is locally exceeded, and the resin-containing inner liner layer is After vulcanization, there was a problem that the bulge protruded to the outside locally.

  In addition, as a method of effectively discharging the air trapped between both members to the outside, a twisted yarn is arranged between both members, and during vulcanization, the air is dispersed to the periphery and discharged to the outside through a gap in the twisted yarn. Techniques to do so are commonly used. However, the twisted yarn cannot be used because the adhesive strength with the resin-blended inner liner member is significantly inferior to that of the rubber member (unvulcanized tire body).

  An object of the present invention is to provide a pneumatic tire capable of effectively dispersing air trapped between a resin-blended inner liner layer member and an unvulcanized tire body and preventing occurrence of defects due to air accumulation. It is in providing the manufacturing method of.

A method for producing a pneumatic tire according to the present invention that achieves the above object includes a resin-blended inner liner that is blended with an unvulcanized tire body having a carcass layer on the tire inner surface and a thermoplastic resin and is laminated on the inner surface of the carcass layer. In the method for producing a pneumatic tire in which a rubber composite material formed by laminating layers is formed and the rubber composite material is pressurized and heated to produce a pneumatic tire, the resin-blended inner liner layer is made of a thermoplastic resin and Constructed using a film blended with a vulcanized elastomer component, and the laminated side surface of the resin-blended inner liner layer is composed of a convex portion in contact with the unvulcanized tire body and a non-contact concave portion, with depth and recess a 0.005~1.5mm is formed in an uneven surface extending in a mesh shape, the contact surface of the convex portion contacts the entire contact area of the convex portion 25% or more and 99% or less of the total area, and the concave portion is an air escape portion in which air trapped between the unvulcanized tire body and the resin-blended inner liner layer moves between the layers and is dispersed to the surroundings. The rubber composite material is molded , and thereafter, the rubber composite material is subjected to the above-described pressure heating step .

In this way, the rubber composite material is molded into a structure having an air escape portion that disperses air around it, so that when the rubber composite material is pressurized and heated, the air escape portion causes the resin-containing inner liner member and the unvulcanized tire body The air trapped in between can be effectively dispersed to the surroundings, so that it is possible to avoid the occurrence of an air pool in which air is concentrated. Therefore, it is possible to prevent defects caused by air accumulation. In order to exert this effect, it is important that the shape maintaining characteristics of the uneven surface are excellent, and in the present invention, the inner liner layer is formed using a film in which a vulcanized elastomer component is blended with a thermoplastic resin. By doing so, although the recess depth is a fine uneven surface of 0.005 to 1.5 mm, excellent shape maintainability of the uneven surface can be obtained, and the occurrence of air accumulation can be favorably avoided.

It is a tire meridian principal part sectional drawing which shows one example of the pneumatic tire manufactured by the manufacturing method of the pneumatic tire of this invention. It is a principal part expanded sectional view which shows an example of the green tire (rubber composite material) shape | molded by the manufacturing method of the pneumatic tire of this invention. It is a principal part expanded sectional view which shows the other example of the green tire (rubber composite material) shape | molded by the manufacturing method of the pneumatic tire of this invention.

  Hereinafter, the configuration of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 shows a pneumatic tire manufactured by the method for manufacturing a pneumatic tire of the present invention, wherein 1 is a tread portion, 2 is a sidewall portion, and 3 is a bead portion. A carcass layer 4 is mounted between the left and right bead portions 3, and both end portions 4 a are folded back from the inside to the outside of the tire so as to sandwich the bead filler 6 around the bead core 5 embedded in the bead portion 3. . A belt layer 7 is disposed on the outer peripheral side of the carcass layer 4 of the tread portion 1.

  In the tire body M having the carcass layer 4 on the inner surface of the tire as described above, the film-shaped resin blending member 8 in which a thermoplastic resin is blended is laminated on the inner surface 4b of the carcass layer 4 as an inner liner layer. Further, a thin buffer rubber layer called a tie rubber layer may be provided between the film-like resin blending member 8 and the carcass layer 4.

  The pneumatic tire having the above-described configuration is manufactured according to a conventionally known manufacturing process. For example, a film-shaped resin compounded member before heating is wound as an inner liner layer on a first molding drum, and an unvulcanized carcass layer is laminated and bonded on the resin compounded member.

  After placing bead cores with unvulcanized bead fillers on the outer periphery at both ends of the carcass layer, both ends of the carcass layer are folded around the bead core. An unvulcanized side rubber layer constituting the sidewall portion 2 and the bead portion 3 is wound around both sides of the carcass layer, and then shaped into a toroidal shape to form a first tire body.

  On the other hand, an unvulcanized belt layer is wound on the second molding drum, and an unvulcanized tread rubber layer constituting the tread portion 1 is disposed on the belt layer to mold the second tire body.

  A second tire body is disposed on the outer peripheral side of the first tire body, and a green tire (rubber composite material) formed by laminating an unvulcanized tire body (unvulcanized rubber member) and a resin compounding member is formed. . Thereafter, the green tire is put into a vulcanizer and heated under pressure and vulcanized to obtain the pneumatic tire.

  In the manufacturing method of the pneumatic tire which consists of such a manufacturing process, this invention is characterized by the following points. That is, as shown in FIGS. 2 to 4, when forming a green tire (rubber composite) G that is in a state before vulcanization of the pneumatic tire, the green tire G is blended with a film-like resin before heating. A structure having an air escape portion for letting air trapped between the inner liner member (resin-mixed inner liner layer) 8 ′ and the unvulcanized carcass layer (part of the unvulcanized tire body) 4 ′ to the surroundings. It is molded.

  FIG. 2 shows that the entire outer side surface (laminated side surface) 8′a of the resin-containing inner liner member 8 ′ is formed as a concave / convex surface composed of a convex portion X1 that contacts the carcass layer 4 ′ and a concave portion Y1 that is not in contact with the concave portion Y1. The air escape part. The concave portion Y1 extends in a mesh shape in the circumferential direction, the oblique direction, and the width direction, and is continuously extended to the edges of both end portions in the tire width direction of the resin-blended inner liner member 8 ′. Further, it may be provided only where it is not necessary to extend over the entire surface, for example, only in a portion corresponding to the tire shoulder portion where air tends to gather during vulcanization. When extending over the entire surface, a part of the air is discharged to the outside, so that it is still better. Further, a thin rubber layer called tie rubber is disposed between the carcass layer 4 ′ and the resin-blended inner liner member 8 ′, and this unevenness is formed on the side of the rubber layer that adheres to the resin-blown inner liner member 8 ′. Also good.

  FIG. 3 shows a structure in which an uncured adhesive layer 9 ′ is laminated on the outer side surface 8′a of the resin-containing inner liner member 8 ′. It has become. In order to secure the adhesion between the resin-blended inner liner member 8 ′ and the carcass layer 4 ′, an adhesive is provided between the resin-blended inner liner member 8 ′ and the carcass layer 4 ′ as necessary. However, here, a co-extruded adhesive layer 9 'is used. The entire outer surface (laminated side surface that is an adhesive surface with the carcass layer 4 ′) 9 ′ a of the adhesive layer 9 ′ is formed on a concavo-convex surface including a convex portion X 3 that contacts the carcass layer 4 ′ and a non-contact concave portion Y 3. The recess Y3 is an air escape portion. The recess Y3 extends in a mesh shape in the circumferential direction, the oblique direction, and the width direction, and continuously extends to the edges of both end portions of the adhesive layer 9 ′ in the tire width direction. Further, only necessary portions may be provided without extending over the entire surface, and this embodiment can be the same as described above.

Instead of this configuration, the resin blended inner liner member 8 ′ is formed in an uneven shape, and the adhesive layer 9 ′ is adhered to the uneven surface with a uniform thickness, whereby the outer surface 9′a of the adhesive layer 9 ′ is formed. You may form in an uneven surface .

  Thus, in the method of forming a green tire formed by laminating the unvulcanized tire body and the resin-blended inner liner member 8 ′ and pressurizing and heating the green tire, The air escape portion that disperses the trapped air around the unvulcanized tire body and the resin-blended inner liner member 8 ′ has a configuration in which air is evacuated during vulcanization by pressure heating. Since it is possible to disperse to the surroundings through the escape portion or discharge to the outside so that the air can be less than the limit amount that can be absorbed or permeated to the surrounding members, the occurrence of defects due to air accumulation is reduced. Can be prevented.

In the present invention, as described above, the air escape portion preferably extends to both edges of each member to discharge air to the outside, but may extend to one edge. . In addition, it is not always necessary to extend to the edge, and the air escape portion is arranged so as to be dispersed so that the air can be absorbed or permeated to the surrounding members so as to be less than the limit amount, so that the trapped air is concentrated. You may make it avoid generation | occurrence | production .

It is important that the total contact area of the convex portions X1, X2, and X3 is 25% or more and 99% or less of the total area of the contact surface with which they contact in the range where the processing as in the present invention is performed. When the total contact area is lower than 25%, the contact area is reduced, and therefore, it is easily peeled off during molding. On the other hand, if it exceeds 99%, the air flow path is blocked and the effect of dispersion becomes low. Preferably, it is 50% or more and 97% or less. More preferably, it is 80% or more and 95% or less .

The depth of the recesses Y1, Y2, and Y3 is important to be 0.005 to 1.5 mm . If the depth is shallower than 0.005 mm, the resin-mixed member 8 ′ and the carcass layer 4 ′ are pressure-bonded. When stacked, the recesses Y1, Y2, and Y3 are closed and brought into close contact by the pressure, so that it is difficult to secure an air escape portion. On the other hand, if the depth is deeper than 1.5 mm, a large amount of air is taken into the concave portion, which may induce air accumulation. More preferably, it is 0.1 mm or more and 0.8 mm or less.

  When forming an uneven surface on the resin-blended inner liner member 8 ', for example, when the resin-blended inner liner member 8' is extruded by an extruder, an extrusion die having one surface or both surfaces uneven is used as a discharge port. It can be easily obtained by installing. Further, the outer side surface 8'a of the resin-blended inner liner member 8 'may be formed into a rough surface or scratched.

  In addition, the uneven surface is brazed by winding the sheet-shaped resin-blended inner liner member 8 'extruded on the uneven winding sheet or by passing between the uneven gear rollers. You can also.

  The shape of the uneven surface may be any shape as long as a sufficient air escape portion can be secured. For example, the wall surface of the convex portion may be changed to a step shape.

The above-described resin-blended inner liner member 8 ′ is composed of a thermoplastic resin elastomer composition obtained by blending a thermoplastic resin and a vulcanized elastomer . Since the resin-containing inner liner member 8 ′ is composed of a thermoplastic resin elastomer composition obtained by blending a thermoplastic resin and a vulcanized elastomer, the shape maintaining property of the uneven surface is very excellent even after molding of the tire. Yes. Examples of the thermoplastic resin include the following thermoplastic resins.

  Polyamide resins (for example, nylon 6 (N6), nylon 66 (N66), nylon 46 (N46), nylon 11 (N11), nylon 12 (N12), nylon 610 (N610), nylon 612 (N612), nylon 6 / 66 copolymer (N6 / N66), nylon 6/66/610 copolymer (N6 / 66/610, nylon MXD6 (MXD6), nylon 6T, nylon 6 / 6T copolymer, nylon 66 / PP copolymer , Nylon 66 / PPS copolymer), and N-alkoxyalkylated products thereof such as 6-nylon methoxymethylated product, 6-610-nylon methoxymethylated product, 612-nylon methoxymethylated product, polyester resin ( For example, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyethylene isophthalate (PEI), PET / PEI copolymer, polyarylate (PAR), polybutylene naphthalate (PBN), liquid crystal polyester, polyoxyalkylene diimidic acid / polybutylate terephthalate copolymer Aromatic polyester), polynitrile resin (for example, polyacrylonitrile (PAN), polymethacrylonitrile, acrylonitrile / styrene copolymer (AS), methacrylonitrile / styrene copolymer, methacrylonitrile / styrene / butadiene copolymer) Polymer), polymethacrylate resin (eg, polymethyl methacrylate (PMMA), polyethyl methacrylate), polyvinyl resin (eg, vinyl acetate, polyvinyl alcohol (PVA), vinyl alcohol / ethylene copolymer) (EVOH), polyvinylidene chloride (PDVC), polyvinyl chloride (PVC), vinyl chloride / vinylidene chloride copolymer, vinylidene chloride / methyl acrylate copolymer, vinylidene chloride / acrylonitrile copolymer), cellulose resin (for example, Cellulose acetate, cellulose acetate butyrate), fluororesin (eg, polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF), polychlorofluoroethylene (PCTFE), tetrafluoroethylene / ethylene copolymer), imide resin (eg, Aromatic polyimide (PI)) and the like.

  Further, the thermoplastic elastomer composition containing a blend of the thermoplastic resin and the elastomer can be constituted by mixing the elastomer with the thermoplastic resin described above, and if it has an air permeation preventing function, the material It is not limited to the kind or mixing ratio. Examples of the elastomer blended with the thermoplastic resin include the following.

  Diene rubber and hydrogenated products thereof (for example, NR, IR, epoxidized natural rubber, SBR, BR (high cis BR and low cis BR), NBR, hydrogenated NBR, hydrogenated SBR), olefin rubber (for example, ethylene propylene) Rubber (EPDM, EPM), maleic acid-modified ethylene propylene rubber (M-EPM), IIR, isobutylene and aromatic vinyl or diene monomer copolymer, acrylic rubber (ACM), ionomer), halogen-containing gonet (eg Br-IIR) CI-IIR, brominated product of isobutylene paramethylstyrene copolymer (Br-IPMS), chloroprene rubber (CR), hydrin rubber (CHR), chlorosulfonated polyethylene (CSMM)), silicone rubber (for example, methyl vinyl silicone rubber, Dimethyl silicone rubber, methylphenylbi Silicone rubber), sulfur-containing rubber (for example, polysulfide rubber), fluorine rubber (for example, vinylidene fluoride rubber, fluorine-containing vinyl ether rubber, tetrafluoroethylene-propylene rubber, fluorine-containing silicon rubber, fluorine-containing phosphazene rubber), Examples thereof include thermoplastic elastomers (for example, styrene elastomers, olefin elastomers, ester elastomers, urethane elastomers, polyamide elastomers).

A method for producing a thermoplastic elastomer composition is a method in which a thermoplastic resin component and an elastomer component (unvulcanized product in the case of rubber) are previously melt-kneaded with a twin-screw kneading extruder or the like to form a continuous phase (matrix). By dispersing the elastomer component as a dispersed phase (domain) in the plastic resin. At that time, in the present invention, in particular, a thermoplastic resin and a vulcanized elastomer component are blended to constitute a resin blended inner liner layer, and the elastomer component is vulcanized under the melt kneading, adding a vulcanizing agent under kneading, cause dynamically vulcanize the elastomer component.
Incidentally, a thermoplastic resin or various additives to the elastomer component (except the vulcanizing agent) may be added during the kneading process, it is preferable to pre-mixed before kneading. The kneading machine used for kneading the thermoplastic resin and the elastomer component is not particularly limited, and a screw extruder, a kneader, a Banbury mixer, a biaxial kneading extruder, or the like can be used. Among them, it is preferable to use a twin-screw kneading extruder for kneading the thermoplastic resin and the elastomer component and for dynamic vulcanization of the elastomer component. Further, two or more types of kneaders may be used and kneaded sequentially. As conditions for melt kneading, the temperature may be higher than the temperature at which the thermoplastic resin melts. Moreover, it is preferable that the shear rate at the time of kneading | mixing is 1000-7500Sec < ^-1 >. The total kneading time is preferably 30 seconds to 10 minutes, and the vulcanization time after adding the vulcanizing agent is preferably 15 seconds to 5 minutes.

  When the compatibility between the specific thermoplastic resin and the elastomer component is different from each other, it is preferable to make them compatible by using an appropriate compatibilizing agent as the third component. By mixing a compatibilizer into the system, the interfacial tension between the thermoplastic resin and the elastomer component is reduced, and as a result, the rubber particle size forming the dispersion layer becomes finer, so the characteristics of both components are more It will be expressed effectively. Such a compatibilizing agent is generally a copolymer having both or one structure of a thermoplastic resin and an elastomer component, or an epoxy group, carbonyl group, halogen group, amino group capable of reacting with the thermoplastic resin or elastomer component. A copolymer having a group, an oxazoline group, a hydroxyl group and the like can be taken. These may be selected according to the kind of the thermoplastic resin and the elastomer component to be mixed, and those usually used include styrene / ethylene butylene block copolymer (SEBS) and its maleic acid modified product, EPDM, EPDM / EPDM / Examples thereof include styrene or EPDM / acrylonitrile graft copolymer and a maleic acid modified product thereof, styrene / maleic acid copolymer, and reactive phenoxin. The amount of the compatibilizing agent is not particularly limited, but is preferably 0.5 to 10 parts by weight with respect to 100 parts by weight of the polymer component (the total of the thermoplastic resin and the elastomer component).

  The composition ratio between the specific thermoplastic resin component (A) and the elastomer component (B) in the case of blending the thermoplastic resin and the elastomer is not particularly limited and may be appropriately determined depending on the Young's modulus and the thickness of the molded body. However, the preferred range is 90/10 to 30/70 by weight.

  In addition to the above essential polymer component, the polymer composition according to the present invention may be mixed with other polymers such as the above-described compatibilizer polymer within a range that does not impair the necessary characteristics of the tire polymer composition of the present invention. it can. The purpose of mixing other polymers is to improve the compatibility between the thermoplastic resin and the elastomer component, to improve the molding processability of the molded material, to improve heat resistance, and to reduce costs. Examples of the material used for this include polyethylene (PE), polypropylene (PP), polystyrene (PS), ABS, SBS, polycarbonate (PC), and the like. In the polymer composition according to the present invention, fillers (calcium carbonate, titanium oxide, alumina, etc.), carbon black, white carbon and other reinforcing agents generally blended in polymer blends, softeners, plasticizers, Processing aids, pigments, dyes, anti-aging agents, and the like can be optionally blended so long as the air permeability and Young's modulus requirements are not impaired.

Further, the elastomer component, when mixed with the thermoplastic resin, it is possible to dynamically vulcanize the elastomer component. The vulcanizing agent, vulcanization aid, vulcanization conditions (temperature, time), etc. in the case of dynamically vulcanizing the elastomer component may be appropriately determined according to the composition of the elastomer component to be added, and are particularly limited. It is not a thing.

  A general rubber vulcanizing agent (crosslinking agent) can be used as the vulcanizing agent. Specific examples of the ionic vulcanizing agent include powdered sulfur, precipitated sulfur, highly dispersible sulfur, surface-treated sulfur, insoluble sulfur, dimorpholine disulfide, alkylphenol disulfide, and the like. About 4 phr [parts by weight per 100 parts by weight of rubber component (polymer)] can be used.

  Examples of organic peroxide vulcanizing agents include benzoyl peroxide, t-butyl hydroperoxide, 2,4-dichlorobenzoyl peroxide, 2,5-dimethyl-2,5-di (t-butyl). Peroxy) hexane, 2,5-dimethylhexane-2,5-di (peroxylbenzoate) and the like are exemplified, and for example, about 1 to 20 phr can be used.

  Furthermore, examples of the phenol resin-based vulcanizing agent include bromides of alkyl phenol resins, mixed crosslinking systems containing halogen donors such as tin chloride and chloroprene, and alkyl phenol resins. For example, about 1 to 20 phr is used. Can do.

  In addition, zinc white (about 5 phr), magnesium oxide (about 4 phr), risurge (about 10 to 20 phr), p-quinonedioxime, p-dibenzoylquinonedioxime, tetrachloro-p-benzoquinone, poly-p- Examples include dinitrosobenzene (about 2 to 10 phr) and methylenedianiline (about 0.2 to 10 phr).

  Moreover, you may add a vulcanization accelerator as needed. Examples of the vulcanization accelerator include general vulcanization accelerators such as aldehyde / ammonia, guanidine, thiazole, sulfenamide, thiuram, dithioate, thiourea, etc. About 2 phr can be used.

  Specifically, as the aldehyde / ammonia vulcanization accelerator, hexamethylenetetramine and the like, as the guanidinium vulcanization accelerator, diphenyl guanidine, etc., as the thiazole vulcanization accelerator, dibenzothiazyl disulfide ( DM), 2-mercaptobenzothiazole and its Zn salt, cyclohexylamine salt, etc., sulfenamide vulcanization accelerators include cyclohexylbenzothiazylsulfenamide (CBS), N-oxydiethylenebenzothiazyl- Tetramethylthiuram disulfide (TMTD) is used as a thiuram vulcanization accelerator such as 2-sulfenamide, Nt-butyl-2-benzothiazole sulfenamide, 2- (thymolpolynidithio) benzothiazole and the like. , Tetraethylthiuram disulfide, tetrame Examples of dithioate-based vulcanization centering agents such as rutiuram monosulfide (TMTM) and dipentamethylene thiuram tetrasulfide include Zn-dimethinidithiocarbamate, Zn-diethyldithiocarbamate, and Zn-di-n-butyldithiocarbamate. Zn-ethylphenyldithiocarbamate, Te-diethyldithiocarbamate, Cu-dimethyldithiocarbamate, Fe-dimethyldithiocarbamate, pipecoline pipecolyldithiocarbamate, etc. Examples of thiourea vulcanization accelerators include ethylenethiourea and diethylthiourea Can be mentioned.

  Moreover, as a vulcanization | cure acceleration | stimulation adjuvant, the general rubber adjuvant can be used together, for example, zinc white (about 5 phr), stearic acid, oleic acid, and these Zn salts (about 2-4 phr). Etc. can be used.

The film thus obtained has a structure in which vulcanized elastomer is dispersed as a discontinuous phase in a thermoplastic resin matrix. By adopting such a structure, the film can be provided with sufficient flexibility and sufficient low air permeability due to the effect of the resin layer of the continuous phase, and molding of a thermoplastic resin regardless of the amount of elastomer. And the shape maintaining property of an extremely fine concavo-convex surface such that the recess depth is 0.005 to 1.5 mm can be obtained.

  As the adhesive layer 9 ′, an ordinary rubber-based, phenolic resin-based, acrylic copolymer-based, isocyanate-based polymer and an adhesive in which a crosslinking agent is dissolved in a solvent are applied to a film, and heat and pressure during vulcanization formation are applied. Adhesive resin such as styrene butadiene styrene copolymer (SBS), ethylene ethyl acrylate (EEA, styrene ethylene block copolymer (SEBS)) is coextruded or laminated with a thermoplastic film. There is a method in which a multilayer film is prepared and adhered to rubber at the time of vulcanization.Solvent adhesives include, for example, phenol resin (Chemlock 220, Rhode), chlorinated rubber (Chemlock 205, Chemlock 234B), isocyanate A system (Chemlock 402) etc. can be illustrated.

DESCRIPTION OF SYMBOLS 1 Tread part 2 Side wall part 3 Bead part 4 Carcass layer 4 'Unvulcanized carcass layer (a part of unvulcanized tire main body)
4'b inner side (laminated side)
8 Resin-blended inner liner member 8 'Resin-blended member before heat curing 8'a Outer side (laminated side)
9 'Adhesive layer 9'a Outside surface (adhesive surface)
G Green tire (rubber composite)
M Tire body X1, X2, X3 Convex part Y1, Y2, Y3 Concave part (air escape part)

Claims (2)

A rubber composite material is formed by laminating an unvulcanized tire body having a carcass layer on the inner surface of a tire and a resin-blended inner liner layer blended with a thermoplastic resin and laminated on the inner surface of the carcass layer, and the rubber In the pneumatic tire manufacturing method of manufacturing a pneumatic tire by pressurizing and heating the composite material, the resin-blended inner liner layer is configured using a film blended with a thermoplastic resin and a vulcanized elastomer component, and The laminated side surface of the resin-containing inner liner layer is composed of a convex part that contacts the unvulcanized tire body and a non-contact concave part, and the concave part has a depth of 0.005 to 1.5 mm and the concave part Is formed on a concavo-convex surface extending in a mesh shape, and the total contact area of the convex portion is 25% or more and 99% or less of the total area of the contact surface with which the convex portion contacts, and the concave portion is not added. In the air escape portion trapped air is distributed around moving at interlayer between the tire body resin formulations inner liner layer and molding the rubber composite, thereafter, pressurized mentioned above the rubber composite A method for producing a pneumatic tire, characterized by being subjected to a pressure heating step .   2. The resin blended inner liner layer according to claim 1, wherein an adhesive layer is laminated on a lamination side, and the uneven surface is formed on a laminated side surface that is an adhesion surface of the adhesive layer to the unvulcanized tire body. The manufacturing method of the pneumatic tire of description.

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