PROPPANTS WITH SOLUBLE COMPOSITE COATINGS Russian patent published in 2012 - IPC C09K8/80 B32B5/16 E21B43/267 

FIELD: chemistry.

SUBSTANCE: proppant is a material in form of particles, where each particle contains a proppant particle base, a water-soluble outer coating deposited on said base, and microparticles of an insoluble reinforcing and filling agent, at least partially immersed in the water-soluble outer coating such that said microparticles are essentially released from the proppant particle base when the water-soluble coating dissolves or breaks down. The material in form of particles for improving operation and/or efficiency of a bore hole in an underground formation, having a particle base from the underground formation, a water-soluble outer coating on said base and a reinforcing agent from microparticles at least partially immersed in said coating such that it is essentially released when the water-soluble coating dissolves or breaks down. The method of improving operating characteristics of a bore hole in an underground formation, involving feeding said material into one or more objects selected from an underground formation, a well shaft in said formation or bore hole in said underground formation.

EFFECT: high strength and wear-resistance of the proppant and permeability of the filling made from said proppant.

18 cl, 1 ex, 1 tbl, 4 dwg