JP5228613B2 - Pneumatic tire manufacturing method and pneumatic tire - Google Patents

Description

  The present invention relates to a method for manufacturing a pneumatic tire and a pneumatic tire manufactured by the method, and more particularly, a method for manufacturing a pneumatic tire and a pneumatic tire for improving a vulcanization failure caused by an air pocket. About.

  Conventionally, a pneumatic tire using a thermoplastic resin or a thermoplastic elastomer composition obtained by blending a thermoplastic resin component and an elastomer component for an inner liner layer is well known (for example, see Patent Document 1). Thereby, there is an advantage that the inner liner layer can be reduced in weight and fuel efficiency can be improved.

However, if the inner liner layer is composed of such a thermoplastic resin or thermoplastic elastomer composition, the air taken in between the inner liner layer and the adjacent members during the molding process of the green tire is difficult to escape, and There is a problem that a vulcanization failure due to air remaining between the layers after vulcanization tends to occur.
WO2005 / 007423 Publication

An object of the present invention is to provide a method for manufacturing a pneumatic tire capable of improving a vulcanization failure caused by an air pocket between an inner liner layer made of a thermoplastic resin or a thermoplastic elastomer composition and a member adjacent thereto. And providing a pneumatic tire.

The method for producing a pneumatic tire according to the present invention that achieves the above object is to form a green tire having an inner liner layer composed of a thermoplastic resin or a thermoplastic elastomer composition obtained by blending an elastomer in a thermoplastic resin and then vulcanize the molded tire. the method of manufacturing a pneumatic tire, wherein said adjacent member a path to escape the air remaining between the adjacent members and the inner liner layer adjacent thereto is closed, the path facing the at least an end portion of the inner liner layer In addition, the arrangement density of the path facing the end portion of the inner liner layer is made higher than the portion other than the end portion .

  The pneumatic tire of the present invention is manufactured by the method for manufacturing a pneumatic tire described above.

According to the present invention described above, during vulcanization, air remaining between the inner liner layer made of a thermoplastic resin or a thermoplastic elastomer composition and its adjacent members can be dispersed to the surroundings by a route. It is possible to suppress the occurrence of a large air reservoir that causes a sulfation failure and to improve the vulcanization failure caused by the air remaining between the layers.

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

  FIG. 1 shows an example of a pneumatic tire manufactured by the method for manufacturing a pneumatic tire of the present invention, where 1 is a tread portion, 2 is a sidewall portion, 3 is a bead portion, and CL is a tire equatorial plane.

  A carcass layer 4 embedded in a rubber layer with reinforcing cords extending in the tire radial direction between the left and right bead portions 3 arranged at predetermined intervals in the tire circumferential direction is extended, and both end portions thereof are embedded in the bead portion 3 The bead filler 6 is folded back from the inner side in the tire axial direction so as to sandwich the bead filler 6 around the bead core 5.

  A plurality of belt layers 7 are provided on the outer peripheral side of the carcass layer 4 of the tread portion 1, and a tread rubber layer 8 is disposed on the outer peripheral side of the belt layer 7. Inside the carcass layer 4 is disposed a film-like inner liner layer 9 made of a thermoplastic resin or a thermoplastic elastomer composition obtained by blending an elastomer in a thermoplastic resin.

  A side rubber layer 10 is disposed outside the carcass layer 4 of the sidewall portion 2. A reinforcing layer 11 in which reinforcing cords are arranged and embedded in the rubber layer is disposed outside the folded portion of the carcass layer 4 of the bead portion 3. A rim cushion rubber layer 12 is provided outside the reinforcing layer 12. Reference numeral 13 denotes a belt cushion rubber layer disposed on the edge portion of the belt layer 7.

  Hereinafter, a method for manufacturing the pneumatic tire of FIG. 1 by the manufacturing method of the present invention will be described with reference to FIGS.

  First, as shown in FIG. 2, a cylindrical inner liner layer 9 made of a thermoplastic resin or a thermoplastic elastomer composition is attached on the molding drum 21. Next, as shown in FIG. 3, an unvulcanized carcass layer 4 in which an unvulcanized reinforcing layer 11 is bonded in advance on the inner liner layer 9 is bonded over one circumference. As shown in FIG. 4, the unvulcanized carcass layer 4 adjacent to the inner liner layer 9 causes air remaining between the inner liner layer 9 and the carcass layer 4 on the adjacent surface 4A facing the inner liner layer 9. A path made up of narrow grooves 14 for escaping is provided.

  The narrow grooves 14 that are bent and extended in a cross-sectional shape in the width direction of the unvulcanized carcass layer 4 (the direction that becomes the drum width direction) are longitudinal directions of the unvulcanized carcass layer 4 (drums). (Circumferential direction) arrayed along LO and formed over the entire surface of adjacent surface 4A. Each narrow groove 14 extends to the edge 4E of the uncured carcass layer 4 so as to exceed the edge 9E of the laminated inner liner layer 9.

  Further, on the adjacent surface 11A of the unvulcanized reinforcing layer 11, as shown in FIG. 5, narrow grooves 15 extending in the width direction (the direction of the drum width direction) are arranged at predetermined intervals over the entire surface. Yes. Each narrow groove 15 extends from one end to the other end of the unvulcanized reinforcing layer 11 so as to exceed the edge 9E of the adjacent inner liner layer 9.

  After the unvulcanized carcass layer 4 is attached, the bead core 5 to which the unvulcanized bead filler 6 is attached, the unvulcanized rim cushion rubber layer 12, and the unvulcanized belt cushion rubber layer 13 are attached in the same manner as before. Then, the unvulcanized side rubber layer 10 is attached to form the cylindrical first molded body 23 (see FIG. 6).

  The first molded body 23 is removed from the molding drum 21 and attached to the shaping drum 22 as shown in FIG. 7 to apply internal pressure, thereby expanding the first molded body 23 in a toroidal shape. A green tire is molded by pressure bonding to the inner peripheral side of an annular second molded body 24 in which the unvulcanized tread rubber layer 8 is bonded to the outer peripheral side of the unvulcanized belt layer 7 disposed on the outer peripheral side. This green tire is pressurized and heated in a mold and vulcanized to obtain the pneumatic tire of FIG.

  At the time of vulcanization, air taken in between the inner liner layer 9 and the uncured carcass layer 4 and the reinforcing layer 11 adjacent to the inner liner layer 9 is dispersed to the periphery by the narrow grooves 14 and 15, and air is passed from the end layers. It is possible to prevent the occurrence of a large air pool that causes vulcanization failure by escaping to the outside of the interlayer, so that the vulcanization failure due to the air remaining between the layers can be effectively improved.

  The narrow groove 14 provided in the unvulcanized carcass layer 4 adjacent to the inner liner layer 9 is preferably provided as a whole as shown in FIG. 4, but it is not provided on the center side as shown in FIG. It may be provided on both ends. 4 and 8, the narrow groove 14 extends while inclining in the width direction of the unvulcanized carcass layer 4, but as shown in FIGS. You may make it extend along the width direction.

  The narrow groove 14 shown in FIG. 9 is not provided on the center side, is provided on both ends, and extends beyond the edge 9E of the laminated inner liner layer 9, but is not vulcanized. The carcass layer 4 does not extend to the edge 4E. The narrow groove 14 shown in FIG. 10 is obtained by further extending the narrow groove 14 of FIG. 9 to the edge 4E of the unvulcanized carcass layer 4.

  In the narrow groove 14 shown in FIG. 11, a narrow groove 14A shorter than the narrow groove 14 in FIG. 10 is additionally formed in a region facing the end 9A of the inner liner layer 9, and the narrow groove 14 facing the end 9A is formed. The arrangement density of the grooves is higher than the other portions. On the end portion 9A side of the inner liner layer 9 extending to the bead portion 3, air is particularly easily taken in between the layers for molding. Thus, by increasing the density of the narrow grooves 14 in this way, it is possible to easily release the air remaining on the end side to the outside of the interlayer. The narrow grooves 15 provided in the reinforcing layer 11 disposed in the bead portion 3 may also have a higher arrangement density than the narrow grooves 14.

  The narrow groove 14 shown in FIG. 12 is provided only on the end portion 9A side where air is easily taken in between the layers, and even in this way, the air pool between the layers around the bead portion 3 can be improved.

The total volume per unit area of the narrow grooves 14 and 15 is preferably in the range of 2.0 to 30.0 mm ³ / cm ² . If the total volume per unit area is smaller than 2.0 mm ³ / cm ² , the air between layers cannot be effectively released. If it exceeds 30.0 mm ³ / cm ² , it will cause air retention.

  The depth of the narrow grooves 14 and 15 is preferably 1.0 mm or less. If the depth exceeds 1.0 mm, it will cause air accumulation. The lower limit of the depth should be 0.3 mm or more in order to effectively release the air between layers.

  Instead of the narrow grooves 14 and 15 described above, the path for releasing the air between the layers may be constituted by a breathable yarn (breeder yarn) 16 in which filaments are twisted as shown in FIG. The same effect as described above can be obtained by providing this on the adjacent surface in the same manner as the narrow grooves 14 and 15.

The total volume per unit area of the yarns 16 arranged on the adjacent surface is preferably in the range of 0.5 to 30.0 mm ³ / cm ² . When the total volume per unit area is less than 0.5 mm ³ / cm ² , it becomes difficult to effectively release air between layers. If it exceeds 30.0 mm ³ / cm ² , the unevenness at the interface increases, and as a result, the adhesiveness decreases and causes air retention.

  The number of yarns 16 arranged per unit length is preferably in the range of 10 to 100 yarns / m. If the number of arrays is less than 10 / m, it is difficult to effectively release the air between layers. If it exceeds 100 lines / m, it will cause air accumulation as described above.

  The path for releasing the air between the layers may be constituted by a narrow hole 17 as shown in FIG. 14 instead of the narrow grooves 14 and 15 described above. The same effect as described above can be obtained by providing a plurality of fine holes 17 so as to penetrate through the unvulcanized carcass layer 4 and the reinforcing layer 11.

  As shown in FIG. 14, the narrow holes 17 are preferably provided in the entire uncured carcass layer 4. However, as in the case of the narrow grooves 14, the narrow holes 17 are not provided on the center side, but are provided on both ends. May be. 11 and 12, the arrangement density of the narrow holes 17 is increased in the region facing the end portion 9 </ b> A of the inner liner layer 9, or the inner liner layer 9 extending to the bead portion 3. It may be provided only on the end portion 9A side.

The total area per unit area of the narrow holes 17 on the adjacent surface is preferably in the range of 0.002 to 5.0 mm ² / cm ² . When the total area per unit area is less than 0.002 mm ² / cm ^2, it becomes difficult to effectively release the air between layers. If it exceeds 5.0 mm ² / cm ² , it will cause air retention.

  The diameter (maximum diagonal length) of the narrow hole 17 is preferably 1.5 mm or less. If it is larger than this, air will be trapped. The lower limit value may be any value as long as the total area per unit area is satisfied.

  In the present invention, the thermoplastic resin used for the inner liner layer 9 is, for example, a polyamide resin [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 / 66), 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 their N-alkoxyalkylated products, for example, methoxymethylated products of nylon 6, nylon 6 / 610 copolymer methoxymethylated product, nylon 612 methoxymethylated product, polyester Tellurium resin [for example, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyethylene isophthalate (PEI), PET / PEI copolymer, polyarylate (PAR), polybutylene naphthalate (PBN), liquid crystal polyester, Aromatic polyester such as polyoxyalkylene diimide diacid / polybutylene terephthalate copolymer], polynitrile resin [for example, polyacrylonitrile (PAN), polymethacrylonitrile, acrylonitrile / styrene copolymer (AS), (meth) Acrylonitrile / styrene copolymer, (meth) acrylonitrile / styrene / butadiene copolymer], polymethacrylate resin [for example, polymethyl methacrylate (PMMA), polyethyl methacrylate], poly Nyl resins [eg, vinyl acetate, polyvinyl alcohol (PVA), vinyl alcohol / ethylene copolymer (EVOH), polyvinylidene chloride (PDVC), polyvinyl chloride (PVC), vinyl chloride / vinylidene chloride copolymer, chloride Vinylidene / methyl acrylate copolymer, vinylidene chloride / acrylonitrile copolymer (ETFE)], cellulose resin [eg, cellulose acetate, cellulose acetate butyrate], fluorine resin [eg, polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF), polychlorofluoroethylene (PCTFE), tetrafluoroethylene / ethylene copolymer], an imide resin [for example, aromatic polyimide (PI)] and the like can be preferably used.

  The thermoplastic elastomer composition can be constituted by mixing an elastomer component with the above-described thermoplastic resin component. Examples of the elastomer used include diene rubbers and hydrogenated products thereof [for example, natural rubber (NR), isoprene rubber (IR), epoxidized natural rubber, styrene bradiene rubber (SBR), bradiene rubber (BR, high Cis BR and low cis BR), nitrile rubber (NBR), hydrogenated NBR, hydrogenated SBR], olefin rubber [for example, ethylene propylene rubber (EPDM, EPM), maleic acid modified ethylene propylene rubber (M-EPM), Butyl rubber (IIR), isobutylene and aromatic vinyl or diene monomer copolymer, acrylic rubber (ACM), ionomer], halogen-containing rubber [for example, Br-IIR, CI-IIR, bromine of isobutylene paramethylstyrene copolymer (Br-IPMS), chloroprene rubber (CR), hydride Rubber (CHR), chlorosulfonated polyethylene rubber (CSM), chlorinated polyethylene rubber (CM), maleic acid-modified chlorinated polyethylene rubber (M-CM)], silicone rubber [eg, methyl vinyl silicone rubber, dimethyl silicone rubber, Methyl phenyl vinyl silicon 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) Rubbers], thermoplastic elastomers (for example, styrene elastomers, olefin elastomers, ester elastomers, urethane elastomers, polyamide elastomers) and the like can be preferably used.

  When the above-mentioned specific thermoplastic resin component and the elastomer component are different in compatibility, they can be made compatible by using a suitable compatibilizer as the third component. By mixing the compatibilizer with the blend system, the interfacial tension between the thermoplastic resin and the elastomer component is reduced, and as a result, the particle size of the rubber forming the dispersion layer becomes fine. It will be expressed more effectively. As such a compatibilizing agent, generally a copolymer having a structure of both or one of the thermoplastic resin and the elastomer component, or an epoxy group, a carbonyl group, a halogen group, which can react with the thermoplastic resin or the elastomer component, The structure of a copolymer having an amino 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, but those usually used include styrene / ethylene butylene block copolymer (SEBS) and its maleic acid modified product, EPDM, EPM. EPDM / styrene or EPDM / acrylonitrile graft copolymer and its maleic acid modified product, styrene / maleic acid copolymer, reactive phenoxin and the like. 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 of 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 the film thickness, air permeation resistance, flexibility The weight range (A) / (B) is preferably 10/90 to 90/10, more preferably 15/85 to 90/10.

  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 material, to improve heat resistance, to reduce costs, etc. Examples of the material used 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 arbitrarily added as long as the above elastic modulus requirements are not impaired.

  The elastomer component can also be dynamically vulcanized when mixed with a thermoplastic resin. The vulcanizing agent, vulcanization aid, vulcanization conditions (temperature, time), etc. when dynamically vulcanizing may be appropriately determined according to the composition of the elastomer component to be added, and are not particularly limited. .

  A general rubber vulcanizing agent (crosslinking agent) can be used as the vulcanizing agent. Specific examples of the sulfur 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 [phr: parts by weight per 100 parts by weight of rubber component (polymer)] can be used.

  Organic peroxide vulcanizing agents include benzoyl peroxide, t-butyl hydroperoxide, 2,4-dichlorobenzoyl peroxide, 2,5-dimethyl-2,5-di (t-butyl peroxide). Oxy) hexane, 2,5-dimethylhexane-2,5-di (peroxylbenzoate), etc. 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 10-20 phr), p-quinonedioxime, p-dibenzoylquinonedioxime, tetrachloro-p-benzoquinone, poly-p- Examples thereof 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 and the like, sulfenamide vulcanization accelerators include cyclohexylbenzothiazylsulfenamide (CBS), N-oxydiethylenebenzothiazyl-2- As thiuram vulcanization accelerators such as sulfenamide, Nt-butyl-2-benzothiazole sulfenamide, 2- (thymolpolynyldithio) benzothiazole, tetramethylthiuram disulfide (TMTD), tetraethyl Thiuram disulfide, tetrame Examples of dithioate-based vulcanization accelerators such as lutiuram monosulfide (TMTM) and dipentamethylene thiuram tetrasulfide include Zn-dimethyldithiocarbamate, Zn-diethyldithiocarbamate, Zn-di-n-butyldithiocarbamate, Zn -Ethyl phenyl dithiocarbamate, Te-diethyl dithiocarbamate, Cu-dimethyldithiocarbamate, Fe-dimethyldithiocarbamate, pipecoline pipecolyldithiocarbamate, etc. Examples of thiourea vulcanization accelerators include ethylenethiourea and diethylthiourea be able to.

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. 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. When vulcanizing the elastomer component, a vulcanizing agent may be added under kneading to dynamically vulcanize the elastomer component. Further, various compounding agents (excluding the vulcanizing agent) to the thermoplastic resin or the elastomer component may be added during the kneading, but are preferably mixed in advance 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 entire kneading time is from 30 seconds to 10 minutes, and when a vulcanizing agent is added, the vulcanization time after addition is preferably from 15 seconds to 5 minutes. What is necessary is just to extrude the polymer composition produced by the said method to a cylindrical shape by a usual method using a normal cylindrical film extruder.

  The cylindrical film thus obtained has a structure in which the elastomer component (B) is dispersed as a discontinuous phase in the matrix of the thermoplastic resin (A). By adopting such a structure, the film can be provided with sufficient flexibility and sufficient rigidity due to the effect of the resin layer as a continuous phase, and at the time of molding, regardless of the amount of the elastomer component, Equivalent moldability can be obtained.

  Adhesion between adjacent tire components is performed by applying 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, and heat generated during vulcanization molding. A method of adhering by pressure, or a co-extrusion or lamination with a cylindrical film of an adhesive resin such as styrene butadiene styrene copolymer (SBS), ethylene ethyl acrylate (EEA), styrene ethylene butylene block copolymer (SEBS), etc. Thus, there is a method in which a multilayer laminate is prepared and bonded to an adjacent tire constituent member during vulcanization. Examples of the solvent-based adhesive include phenol resin (Chemlock 220, Rhode), chlorinated rubber (Chemlock 205, Chemlock 234B), isocyanate (Chemlock 402), and the like.

  In the above embodiment, examples of the inner liner layer 9 as a tire constituent member made of a thermoplastic resin or a thermoplastic elastomer composition, and examples of the unvulcanized carcass layer 4 and the reinforcing layer 11 as adjacent members adjacent thereto are given. In this case, a path may be provided in one of the adjacent members of the unvulcanized carcass layer 4 and the reinforcing layer 11.

In the present invention, adjacent members such as those consisting only or rubber that the reinforcing cords embedded in the rubber layer may be any of the neighboring members if adjacent members.

The above-mentioned path disperses the air remaining in the surroundings even if it is provided not only facing the end part side of the inner liner layer made of a thermoplastic resin or thermoplastic elastomer composition but facing only the central part side. However, it is preferable to provide at least the end side so that the dispersed air can be further exhausted to the outside between the layers. So good.

  As shown in FIGS. 15 and 16, the path for releasing the remaining air may be appropriately combined with the narrow groove 14, the breathable thread 16, and the narrow hole 17.

The tire size is common to 295 / 75R22.5, the inner liner layer is made of a vinyl alcohol / ethylene copolymer, and the narrow grooves shown in FIGS. 10 to 11 are provided on the adjacent surface of the unvulcanized carcass layer adjacent to the inner liner layer. 5 pneumatic tires each having the structure shown in FIG. 1 were produced by the above method (Reference Examples 1 to 3, Example 1 ) and a conventional method (conventional example) in which no narrow groove was provided.

  The narrow groove in FIG. 10 is obtained by providing a narrow groove from point A in FIG. 1 to the edge of the carcass layer. The narrow groove in FIG. 11 is obtained by adding a shorter narrow groove to the narrow groove in FIG. 10, and the short narrow groove is provided from the point C in FIG. 1 to the edge of the carcass layer. The groove volume and depth of the narrow groove are as shown in Table 1.

  For each tire produced, index the number and degree of NG judgment in the shearography test (index by adding the area of the air reservoir in the shearography image), and air between the inner liner layer and the carcass layer When the retention inhibition property was evaluated (conventional example 100), the results shown in Table 1 were obtained.

  From Table 1, it can be seen that the present invention can improve air retention. In addition, it can be seen that further improvement can be achieved by increasing the arrangement density of the narrow grooves at the end.

A method in which the tire size is the same as in Example 1, the inner liner layer is composed of a vinyl alcohol / ethylene copolymer, and a bleeder yarn is provided on the adjacent surface of the unvulcanized carcass layer adjacent thereto (Reference Examples 4 to 6). In Example 2 ), five pneumatic tires each having the structure shown in FIG. 1 were produced.

In Reference Examples 4 to 6 , a bleeder yarn is provided in place of the narrow groove at the same position as Reference Example 1. In this second embodiment, a bleeder yarn is provided in place of the narrow groove at the same position as in the first embodiment . The total volume and the number of arrays of bleeder yarns are as shown in Table 2.

  In each of the produced tires, as in Example 1, the number and degree of NG judgment in the shearography test were indexed to evaluate the air retention suppression between the inner liner layer and the carcass layer (conventional example of Example 1). The results shown in Table 2 were obtained.

  From Table 2, it can be seen that the present invention can improve air retention. It can also be seen that further improvement can be achieved by increasing the arrangement density of the bleeder yarns at the ends.

A method in which the tire size is the same as in Example 1, the inner liner layer is made of a vinyl alcohol / ethylene copolymer, and a fine hole is provided on the adjacent surface of the unvulcanized carcass layer adjacent thereto (Reference Examples 7 to 9). In Example 3 ), five pneumatic tires each having the structure shown in FIG. 1 were produced.

In Reference Examples 7 to 9 , thin holes are provided in the same positions as in Reference Example 1 instead of the narrow grooves. In the third embodiment , a narrow hole is provided at the same position as the first embodiment in place of the narrow groove. Table 2 shows the total area and diameter of the narrow holes.

  In each of the produced tires, as in Example 1, the number and degree of NG judgment in the shearography test were indexed to evaluate the air retention suppression between the inner liner layer and the carcass layer (conventional example of Example 1). The results shown in Table 3 were obtained.

  From Table 3, it can be seen that the present invention can improve air retention. It can also be seen that the density can be further improved by increasing the density of the narrow holes at the end.

It is a tire meridian half section view showing one embodiment of a pneumatic tire manufactured by a manufacturing method of a pneumatic tire of the present invention. It is explanatory drawing which shows the process of attaching an inner liner layer in one Embodiment of the manufacturing method of the pneumatic tire of this invention. It is explanatory drawing which shows the process of attaching a carcass layer in one Embodiment of the manufacturing method of the pneumatic tire of this invention. It is explanatory drawing which shows an example of the narrow groove provided in the adjacent surface of the unvulcanized carcass layer. It is explanatory drawing which shows an example of the narrow groove provided in the adjacent surface of the unvulcanized reinforcement layer. In one Embodiment of the manufacturing method of the pneumatic tire of this invention, it is explanatory drawing which shows the state which shape | molded the 1st molded object on the forming drum. In one Embodiment of the manufacturing method of the pneumatic tire of this invention, it is explanatory drawing which shows the process of expanding a 1st molded object, crimping | bonding it to a 2nd molded object, and shape | molding a green tire. It is explanatory drawing which shows the other example of the narrow groove provided in the adjacent surface of the unvulcanized carcass layer. It is explanatory drawing which shows the further another example of the narrow groove provided in the adjacent surface of the unvulcanized carcass layer. It is explanatory drawing which shows the further another example of the narrow groove provided in the adjacent surface of the unvulcanized carcass layer. It is explanatory drawing which shows the further another example of the narrow groove provided in the adjacent surface of the unvulcanized carcass layer. It is explanatory drawing which shows the further another example of the narrow groove provided in the adjacent surface of the unvulcanized carcass layer. It is explanatory drawing which shows the example of the air permeable thread | yarn provided in the adjacent surface of the unvulcanized carcass layer. It is explanatory drawing which shows the example of the fine hole provided in the adjacent surface of an unvulcanized carcass layer. It is explanatory drawing which shows the further another example of the path | route which escapes the remaining air. It is explanatory drawing which shows the further another example of the path | route which escapes the remaining air.

Explanation of symbols

4 Carcass layer (adjacent member)
4A Adjacent surface 4E Edge 9 Inner liner layer (tire component)
9A End portion 9E Edge 11 Reinforcing layer (adjacent member)
14, 14A, 15 Narrow groove (path)
16 Breathable thread (path)
17 Narrow hole (path)

Claims (11)

In a method for manufacturing a pneumatic tire in which a green tire having an inner liner layer made of a thermoplastic resin or a thermoplastic elastomer composition in which an elastomer is blended in a thermoplastic resin is molded and then vulcanized, the inner liner layer is adjacent to the inner liner layer. arrangement density of said path to escape the air remaining adjacent members possess, together with the path facing the at least an end portion of the inner liner layer, facing the end of the inner liner layer path between adjacent members The manufacturing method of the pneumatic tire which made it higher than parts other than an edge part . The extending between the inner liner layer is left and right bead portions, the manufacturing method of the pneumatic tire according to claim 1, wherein the adjacent member is positioned adjacent to at least an end portion of the inner liner layer in the bead portion . The method for manufacturing a pneumatic tire according to claim 1 or 2 , wherein the path includes a narrow groove provided on an adjacent surface facing an inner liner layer of the adjacent member. The method of a pneumatic tire according to claim 3 , wherein the depth of the narrow groove is 1.0 mm or less. The manufacturing method of the pneumatic tire of Claim 1 or 2 which the said path | route consists of a breathable thread | yarn provided on the adjacent surface which faces the inner liner layer of the said adjacent member. The method for producing a pneumatic tire according to claim 5 , wherein the number of yarns arranged per unit length is 10 to 100 yarns / m. The method for manufacturing a pneumatic tire according to claim 3, wherein the path extends to an edge of the adjacent member. The manufacturing method of the pneumatic tire of Claim 1 or 2 which the said path | route consists of several through-holes provided in the adjacent surface which faces the inner liner layer of the said adjacent member. The method for manufacturing a pneumatic tire according to claim 8 , wherein a total area per unit area of the narrow holes on the adjacent surface is 0.002 to 5.0 mm ² / cm ² . The method for manufacturing a pneumatic tire according to claim 8 or 9 , wherein the diameter of the narrow hole is 1.5 mm or less. The pneumatic tire manufactured by the manufacturing method of the pneumatic tire of any one of Claims 1 thru | or 10 .

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