| abstract |
The present invention provides a slurry additive that, when used in a construction slurry (for example, in a drilling mud or drilling cement slurry used in well drilling, etc.) or the like, is low cost and can suppress dehydration at high temperatures as well as viscosity increase. The present invention is a powdered slurry additive that contains a vinyl alcohol polymer, the vinyl alcohol polymer having a solubility of 25% or less when soaked for 3 hours in 60 °C hot water, a degree of saponification of 99.5 mol% or more, an average degree of polymerization of 1,500-4,500, and a 1,2-glycol bond content of 1.8 mol% or less. The slurry additive passes through a sieve that has a nominal opening of 1.00 mm. |