摘要 |
PURPOSE:To provide a W/O bituminous emulsion which well penetrates into the interior of roadbed without causing environmental pollution or any troubles and can increase waterproofness of the surface of the roadbed, by emulsifying an oil phase consisting of a bituminous substance, a solvent and a fatty acid and a water phase consisting of an aq. alkaline soln. CONSTITUTION:A W/O bituminous emulsion is obtd. by emulsifying an oil phase consisting of a bituminous substance (e.g. straight asphalt), a solvent (e.g. petroleum naphtha) and a fatty acid (e.g. oleic acid) and a water phase consisting of an aq. alkaline soln. (e.g. an aq. magnesium hydroxide soln.). Disadvantages such as malodor and toxicity in herent to cutback materials as conventioned primer coating material can be eliminated by the use of the solvent and accidents such as fire hay and can be prevented by the use of water. Unlike O/W bituminous material, the breaking of the emulsion is not caused by the contact of the emulsion with an aggregate. Since hardening is caused by the evaporation of the solvent and water, a film is hardly formed by curing on the surface of a roadbed and hence, the emulsion penetrates deeply until it is hardened. Accordingly, the emulsion does not adhere to the tire of a construction working car.
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