INJECTION MATERIAL, PROCESS FOR PRODUCTION OF INJECTION MATERIAL, AND INJECTION METHOD

摘要

Disclosed are: an injection material which can achieve high permeability and has excellent water cut-off effect and durability; and an injection method. The injection material comprises a mixture of a material (A) which has been subjected to a wet-mode dispersion treatment and comprises a microparticulate silica, a dispersing agent and water and a material (B) which has been subjected to a wet-mode grinding/dispersion treatment and comprises a calcium compound having an average particle diameter of 1.0 µm or less, a dispersing agent and water, wherein the microparticulate silica is produced by a method comprising burning a slurry comprising a metal silicon powder dispersed in water by ejecting the slurry into flame to oxidize the metal silicon powder and has an average particle diameter of 1.0 µm or less. The average particle diameter is measured using a laser diffraction particle size distribution meter without the need of any ultrasonic dispersion treatment. It is preferred that the microparticulate silica is a microparticulate spherical silica having an average sphericity of 95% or more, the calcium compound is hydroxide calcium, and the injection material additionally contains a curing time controlling agent. It is also preferred that the material (A) and/or the material (B) is produced using a grinder that utilizes high-pressure water.