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:
Mar. 12, 2013
Filed:
Apr. 23, 2010
Renliang Xu, Pembroke Pines, FL (US);
Yiming Yang, Ichigawa, JP;
Renliang Xu, Pembroke Pines, FL (US);
Yiming Yang, Ichigawa, JP;
Beckman Coulter, Inc., Brea, CA (US);
Abstract
Mixtures containing homogeneously-sized particles with a minimum concentration of agglomerates or larger particles are desired in various manufacturing processes such as, for example, in the manufacture and use of chemical mechanical polishing slurries, food emulsions, pharmaceutical products, paints, and print toner. The method disclosed herein provides these industries with an accurate and efficient method of screening such mixtures for such agglomerates and large particles. The method generally includes preparing a suspension of the mixture in an electrolyte, wherein the suspension includes a specified concentration of small particles per unit of electrolyte. The method further includes passing the prepared suspension, and a plurality of the particles therein, through an aperture of a device capable of characterizing particles according to the Coulter principle to obtain data on the particles. Still further, the method includes deriving a particle size distribution of the large particles from the obtained data. The suspension includes at least one small particle per aperture volume. The large particles have an average diameter that is at least five times greater than the average diameter of the small particles. The aperture has a diameter that is (i) at least 50 times greater than the average diameter of the small particles, and (ii) about 1.2 times greater than the average diameter of the large particles to less than about 50 times greater than the average diameter of the large particles.