| 摘要 |
The present invention relates to coated particulate matter wherein the particles are individually coated with a cured combination of phenolic/furan resin or furan resin to form a precured resin coating on a proppant such as sand, thereby substantially improving the chemical resistance of the proppant over one having a straight phenolic precured coating. Another embodiment of this invention involves the use of multiple resin coatings on the particulate matter to form a final layered coating containing the desired amount of cured resin. This multiple coating of particulate material results in a final coated product that has a smoother and more uniform surface than particulate material having its entire resin coating applied in a single operation. 26-14 |
