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:
May. 04, 1993
Filed:
Apr. 22, 1992
William Bauer, Jr, Huntingdon Valley, PA (US);
Nelson I Quiros, North Wales, PA (US);
Rohm and Haas Co., Philadelphia, PA (US);
Abstract
The present invention provides a method of reducing the levels of protoanemonin present in aqueous monomer solutions by adding an effective amount of one or more para-phenylenediamines having the formula: ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are the same or different radical selected from hydrogen, methyl, ethyl, n-propyl, iso-propyl, phenyl or methoxyphenyl with the proviso that at least one of R.sub.1, R.sub.2, R.sub.3 and R.sub.4 is hydrogen; R.sub.5, R.sub.6, R.sub.7 and R.sub.8 are the same or different radical selected from hydrogen, methyl, ethyl, n-propyl, iso-propyl, methoxy or ethoxy with the proviso that at least one of R.sub.5, R.sub.6, R.sub.7 and R.sub.8 is hydrogen; and salts thereof.