TECHNOLOGY FOCUS - POLYMERS - Preferred Condition: The internal pressure is not less than 200 kPa. Preferred Component: The continuous phase of the composite body is made of at least one resin having a polar functional group in their molecule and polyolefin resins. The resin is polyvinyl alcohol resin, acrylonitrile copolymer, an acrylic copolymer, vinylidene chloride copolymer, acrylonitrile/styrene resin, polyester resin, and/or nylon resin. The polyolefin resin is polyethylene resin, polypropylene resin, and/or polystyrene/polyethylene copolymer. The continuous phase is made of a polyvinyl chloride resin. The acrylonitrile polymer is acrylonitrile polymer, acrylonitrile/methacrylonitrile copolymer, acrylonitrile/methyl methacrylate copolymer, and/or acrylonitrile/methacrylonitrile/methyl methacrylate terpolymer; and has a glass transition point of not less than 80 degreesC. The acrylic polymer is methyl methacrylate resin, methyl methacrylate/acrylonitrile copolymer, methyl methacrylate/methacrylonitrile copolymer, and/or methyl methacrylate/acrylonitrile/methacrylonitrile terpolymer. The vinylidene chloride terpolymer is vinylidene chloride/acrylonitrile copolymer, vinylidene chloride/methyl methacrylate copolymer, vinylidene chloride/methacrylonitrile copolymer, vinylidene chloride/acrylonitrile/methacrylonitrile copolymer, vinylidene chloride/acrylonitrile/methyl methacrylate copolymer, vinylidene chloride/methacrylonitrile/methyl methacrylate copolymer, vinyl chloride/acrylonitrile/methacrylonitrile/methyl methacrylate copolymer, and has a glass transition of not less than 80 degreesC. The nylon resin is nylon-6, nylon-11, nylon-12, nylon-6/66 copolymer, or nylon-6/12 copolymer. The continuous phase can be made of at least one nylon resin, butyl rubber, or a diene rubber. An inner liner is provided on the inner peripheral face of the tire and made of thermoplastic elastomer composition containing nylon resin having a melting point of 170-230 degreesC and a halide of isobutylene-para-methylstyrene copolymer in which an elastomer ingredient is dynamically cured to a gelation ratio of 50-95%. The composite body is formed by expanding a foaming composition containing 1-50 wt.% foaming agent. The foaming composition is resin particles sealing the foaming agent. The foaming agent is thermal-decomposable foaming agent, a liquefied fluoride of ethane, and/or a liquefied linear, alicyclic, and/or branched aliphatic hydrocarbon having 3-6C and fluoride. The thermal-decomposable foaming agent is dinitrosopentamethylene tetramine, azodicarbon amide, paratoluene sulfonyl hydrazine or its derivative, or oxybisbenzenesulfonyl hydrazine. Preferred Property: The continuous phase has a gas permeability constant at 30 degreesC of not more than 300x10-12, preferably 2x10-12 (cc.cm/cm2.s.cmHg). The inner liner has a gas permeability constant at 30 degreesC of not more than 20x10-12 (cc.cm/cm2.s.cmHg).    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Component: The at least one gas is nitrogen, air, carbon dioxide, 3-6C aliphatic hydrocarbon, 3-6C alicyclic hydrocarbon, or 2-6 C aliphatic fluorocarbon or fluorohydrocarbon; and contains no chlorine in the closed cell. A gas containing not more than 50 wt.% from propane, n-butane, isobutane, pentane, isopentane, and/or neopentene included in the 2-6C aliphatic fluorocarbon or fluorohydrocarbon and containing no chorine is included in the closed cells. EXAMPLE - A tire was prepared by applying a composite body having resin or composition constituting continuous phase of composite body, closed cell (95 vol.%) at 300 kPa with nitrogen, Vinyhole AC3 (0.36 kg) as foaming agent, Cellpaste 101W (0.1 kg), and inner liner rubber layer (acrylonitrile/methacrylonitrile copolymer). It had 0.2% increase of deflection quantity of tire after the running on drum over 5000 km, and no trouble at 500 km runnable distance of tire after subjected to external injury.