04493875 is referenced by 158 patents and cites 14 patents.

The novel proppant consists of composite particles, the core of which is a conventional proppant particle such as silica sand. The core has a thin, void-containing coating which provides an overall density approaching that of the fracturing fluid. The coating preferably comprises hollow glass microspheres embedded in an adhesive which bonds the microspheres to the core.

Title
Proppant for well fractures and method of making same
Application Number
6/559965
Publication Number
4493875
Application Date
December 9, 1983
Publication Date
January 15, 1985
Inventor
Richard B Castle
St. Paul
MN, US
Warren R Beck
St. Paul
MN, US
Agent
Douglas B Little
James A Smith
Donald M Sell
Assignee
Minnesota Mining and Manufacturing Company
MN, US
IPC
B32B 7/02
B32B 3/14
B32B 1/00
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