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.

Date of Patent:
Dec. 24, 2019

Filed:

Feb. 29, 2016
Applicant:

Purdue Research Foundation, West Lafayette, IN (US);

Inventors:

Bryan William Boudouris, Lafayette, IN (US);

Robert Randell Dodd, Indianapolis, IN (US);

Jessica L. Sargent, West Lafayette, IN (US);

Emily Alcorace, La Crescenta, CA (US);

Assignee:

Purdue Research Foundation, West Lafayette, IN (US);

Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
C09D 11/17 (2014.01); C09D 11/20 (2006.01); C09D 11/16 (2014.01); B43K 8/04 (2006.01); B43K 8/06 (2006.01);
U.S. Cl.
CPC ...
C09D 11/17 (2013.01); B43K 8/04 (2013.01); C09D 11/16 (2013.01); C09D 11/20 (2013.01); B43K 8/06 (2013.01);
Abstract

An ink and method of conducting an examination suitable for reducing the likelihood that the students' answers on paper-based examinations may be changed at a later time prior to being graded. The ink includes a solution of marking particles, a suspension material, and a preserving material. A mark made with the ink is initially erasable for a predetermined period of time after the mark is formed and after the expiration of the predetermined period of time the mark is not erasable. The method of conducting an examination includes providing an ink to an individual, and then providing questions to an individual wherein the individual indicates answers to the questions by producing marks with the ink.


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