Method for manufacturing bladder for use in manufacturing tires

A method for manufacturing a bladder for use in manufacturing tires that comprises a surface-modified rubber layer on an outer surface side of a base rubber layer, comprising the steps of:

• forming an uncross-linked body of the surface-modified rubber layer by molding a rubber composition including a modified butyl rubber composition (A) or (B) and an organic peroxide and applying a siloxane compound having a (meth)acryloyl group to a surface of this rubber molded body;
• wherein the modified butyl rubber composition (A) comprises a modified butyl rubber (1) formed by reacting with butyl rubber a compound (a) having a nitroxide free radical in a molecule that is stable at ambient temperature in the presence of oxygen, a radical initiator (b), and a radical polymeric monomer (c) having at least difunctionality;
• and the modified butyl rubber composition (B) is formed by compounding the monomer (c) with a modified butyl rubber (2) formed by reacting the compound (a) and the radical initiator (b) with butyl rubber;
• forming the base rubber layer from an unvulcanized body or vulcanized body formed from a rubber composition different than the modified butyl rubber compositions (A) and (B);
• laminating the uncross-linked body of the surface-modified rubber layer on the outer surface side of the base rubber layer;
• and
• heat treating.