The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 14, 2015
Filed:
Sep. 07, 2011
Stephen E. Amos, Minneapolis, MN (US);
Robert W. Hunter, Burnsville, MN (US);
Ronald J. Israelson, Lake Elmo, MN (US);
Towako Takeishi, Kawaksakai, JP;
Mark J. Williams, Cottage Grove, MN (US);
Takujiro Yamabe, Sagamihara, JP;
Stephen E. Amos, Minneapolis, MN (US);
Robert W. Hunter, Burnsville, MN (US);
Ronald J. Israelson, Lake Elmo, MN (US);
Towako Takeishi, Kawaksakai, JP;
Mark J. Williams, Cottage Grove, MN (US);
Takujiro Yamabe, Sagamihara, JP;
3M Innovative Properties Company, St. Paul, MN (US);
Abstract
The present disclosure provides a plurality of glass bubbles having an average true density of up to about 0.55 grams per cubic centimeter and a size distribution including a median size in a range from about 15 micrometers to 40 micrometers. A hydrostatic pressure at which ten percent by volume of the plurality of glass bubbles collapses is at least about 100 megapascals. In some embodiments, the plurality of glass bubbles is a graded fraction preparable by classifying a second plurality of glass bubbles, wherein the second plurality of glass bubbles has a higher percentage of glass bubbles with a size of up to ten micrometers than the first plurality of glass bubbles. Composites including the plurality of glass bubbles are also disclosed.