Tire puncture sealant

Abstract

A tire puncture sealant including a urethane emulsion, an acrylic emulsion or a polyolefin emulsion, and an antifreezing agent has a comparatively low viscosity and an excellent storage stability while showing sealing properties equivalent to those of a conventional tire puncture sealant. A tire puncture sealant including a synthetic resin emulsion and an antifreezing agent, and having a hydrogen ion exponent of 5.5 to 8.5 has a less pungent odor and hardly causes corrosion of steel cord. A tire puncture sealant including a chloroprene emulsion and an antifreezing agent and having a hydrogen ion exponent of less than 9.0 has a comparatively low viscosity and a less odor while showing sealing properties equivalent to those of a conventional tire puncture sealant.

1 . A tire puncture sealant comprising a urethane emulsion and an antifreezing agent. 
     
     
         2 . The tire puncture sealant according to  claim 1 , wherein the urethane emulsion is obtained by reacting an ionizable group-containing urethane prepolymer with a neutralizing agent or a quaternizing agent in water. 
     
     
         3 . The tire puncture sealant according to  claim 2 , wherein the urethane prepolymer is obtained by copolymerizing a polyisocyanate compound (A) having two or more isocyanate groups, a compound (B) having two or more active hydrogen atoms, and a compound (C) having a group reactive to isocyanate group and an ionizable group. 
     
     
         4 . The tire puncture sealant according to  claim 2 , wherein the ionizable group is an anionic group. 
     
     
         5 . The tire puncture sealant according to  claim 3 , wherein the compound (B) is .a polyol compound. 
     
     
         6 . The tire puncture sealant according to  claim 5 , wherein the polyol compound is at least one selected from the group consisting of polyether polyol, polycaprolactone polyol, polycarbonate polyol, and polyester polyol. 
     
     
         7 . The tire puncture sealant according to  claim 1 , wherein a content of the antifreezing agent is 100 to 500 parts by weight with respect to 100 parts by weight of a solid content of the urethane emulsion. 
     
     
         8 . The tire puncture sealant according to  claim 1 , further comprising a tackifier. 
     
     
         9 . The tire puncture sealant according to  claim 8 , wherein the tackifier is in the form of an emulsion obtained by emulsifying a resin. 
     
     
         10 . The tire puncture sealant according to  claim 8 , wherein the tackifier contains at least one selected from the group consisting of a rosin resin, a terpene resin, and a hydrogenated terpene resin. 
     
     
         11 . The tire puncture sealant according to  claim 8 , wherein a solid content of the tackifier is 50 to 200 parts by weight with respect to 100 parts by weight of the solid content of the urethane emulsion. 
     
     
         12 . The tire puncture sealant according to  claim 1 , wherein the tire puncture sealant has a hydrogen ion exponent of 5.5 to 8.5.