Method for Manufacturing Pneumatic Tire

Abstract

A pneumatic tire is formed by winding a sheet member (A) and a sheet member (B) onto a molding drum and molding a cylindrical body. A laminate body (M) in which the sheet member (B) is layered in advance on the outer periphery of the sheet member (A) is wound onto a molding drum ( 10 ), the tack value of a material (a) constituting the sheet member (A) being smaller than the tack value of a material (b) constituting the sheet member (B), the length of the sheet member (A) being configured so that a starting end (As) of winding on the molding drum ( 10 ) and an ending end (Ae) of winding do not overlap, and the length of the sheet member (B) being configured so that the ending end (Be) of winding extends longer in the circumferential direction than the ending end (Ae) of winding of the sheet member (A).

1 . A method for manufacturing a pneumatic tire having a step for winding a sheet member (A) and a sheet member (B) onto a molding drum and molding a cylindrical body, the method comprising the steps of:
 combining the sheet member (A) with the sheet member (B) so that a tack value of a material (a) constituting the sheet member (A) is smaller than a tack value of a material (b) constituting the sheet member (B);   winding, on the molding drum, a laminate body obtained by layering in advance the sheet member (B) on an outer periphery of the sheet member (A);   configuring a length of the sheet member (A) so that a starting end of winding of the sheet member (A) does not overlap with an ending end of winding of the sheet member (A) on the molding drum; and   configuring a length of the sheet member (B) so that at least an ending end of winding of the sheet member (B) extends longer in a circumferential direction than the ending end of winding of the sheet member (A),   wherein the ending end of winding of the sheet member (B) is overlapped with and joined on an outer diameter side of a starting end of winding of the sheet member (B).   
     
     
         2 . The method for manufacturing a pneumatic tire according  claim 1 , wherein a plurality of the laminate bodies are overlapped and wound on the molding drum, and joint portions of the respective laminate bodies are arranged so as not to overlap in a radial direction. 
     
     
         3 . The method for manufacturing a pneumatic tire according  claim 1 , wherein a plurality of the laminate bodies are overlapped and wound on the molding drum, and end portions of sheet members (A) of the respective laminate bodies are arranged so as to be mutually separated by 10% or more of a tire circumferential length. 
     
     
         4 . The method for manufacturing a pneumatic tire according to  claim 1 , wherein the material (a) is a thermoplastic resin composition including a thermoplastic resin and an elastomer, and the thermoplastic resin is a continuous phase and the elastomer is a dispersed phase. 
     
     
         5 . The method for manufacturing a pneumatic tire according to  claim 4 , wherein the thermoplastic resin composition is composed of a thermoplastic resin and an elastomer, and a percentage of the elastomer is from 50 to 85 weight % when a sum of the thermoplastic resin and elastomer is 100 weight %. 
     
     
         6 . The method for manufacturing a pneumatic tire according to  claim 4 , wherein the thermoplastic resin composition includes at least one type of thermoplastic resin selected from a polyamide resin, a polyvinyl resin, and a polyester resin. 
     
     
         7 . The method for manufacturing a pneumatic tire according to  claim 1 , wherein the material (b) is a rubber composition consisting of at least one selected from natural rubber, isoprene rubber, styrene butadiene rubber, butadiene rubber, butyl rubber, and halogenated butyl rubber. 
     
     
         8 . The method for manufacturing a pneumatic tire according to  claim 1 , wherein the sheet member (B) and the sheet member (A) are bonded using an adhesive composition, and the adhesive composition includes a compound represented by formula (1) below or a condensate of the compound represented by formula (1) below and formaldehyde. 
       
         
           
           
               
               
           
         
         wherein R 1 , R 2 , R 3 , R 4  and R 5  are hydrogen, a hydroxyl group or an alkyl group having from 1 to 8 carbons) 
       
     
     
         9 . The method for manufacturing a pneumatic tire according to  claim 1 , wherein the pneumatic tire is molded so that an end in the circumferential direction thereof inclines at an angle of from 10° and 85° relative to a tire circumferential direction. 
     
     
         10 . The method for manufacturing a pneumatic tire according to  claim 1 , wherein the starting end of winding of the sheet member (B) is made to extend longer in the circumferential direction than the starting end of winding of the sheet member (A). 
     
     
         11 . The method for manufacturing a pneumatic tire according to  claim 1 , wherein a band-like member is applied on an outer periphery of the sheet member (B) so as to cover a joint portion of the starting end of winding and ending end of winding of the sheet member (B), and a tensile stress at a time of 20% elongation at 25° C. of a material (c) constituting the band-like member is from 1 to 3 times a tensile stress at a time of 20% elongation at 25° C. of the material (a). 
     
     
         12 . The method for manufacturing a pneumatic tire according to  claim 1 , wherein the molding drum has a mechanism for adhering the sheet member (A) to a portion of a drum surface. 
     
     
         13 . The method for manufacturing a pneumatic tire according to  claim 1 , wherein the sheet member (A) is an inner liner. 
     
     
         14 . The method for manufacturing a pneumatic tire according to  claim 1 , wherein the joint portion of the laminate body and a joint portion of a carcass layer overlap in the radial direction when the laminate body is wound on the molding drum and the carcass layer is wound on the outer periphery of the laminate body. 
     
     
         15 . The method for manufacturing a pneumatic tire according to  claim 1 , wherein after the sheet member (A) undergoes biaxial oriented processing, the sheet member (B) is layered on the outer periphery of the sheet member (A). 
     
     
         16 . A pneumatic tire obtained by the method for manufacturing a pneumatic tire described in  claim 1 . 
     
     
         17 . The method for manufacturing a pneumatic tire according  claim 2 , wherein a plurality of the laminate bodies are overlapped and wound on the molding drum, and end portions of sheet members (A) of the respective laminate bodies are arranged so as to be mutually separated by 10% or more of a tire circumferential length. 
     
     
         18 . The method for manufacturing a pneumatic tire according to  claim 17 , wherein the material (a) is a thermoplastic resin composition including a thermoplastic resin and an elastomer, and the thermoplastic resin is a continuous phase and the elastomer is a dispersed phase. 
     
     
         19 . The method for manufacturing a pneumatic tire according to  claim 18 , wherein the thermoplastic resin composition is composed of a thermoplastic resin and an elastomer, and the elastomer is from 50 to 85 weight % when a sum of the thermoplastic resin and elastomer is 100 weight %. 
     
     
         20 . The method for manufacturing a pneumatic tire according to  claim 19 , wherein the thermoplastic resin composition includes at least one type of thermoplastic resin selected from a polyamide resin, a polyvinyl resin, and a polyester resin.