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:
Sep. 11, 1990
Filed:
Jul. 28, 1989
Jeffrey S Pontius, Amanda, OH (US);
Columbus Industries, Inc., Ashville, OH (US);
Abstract
A filter pad for range hoods is disclosed which comprises a plurality of sheets formed of wood paper pulp fiber material. Each sheet is slit and expanded to form a plurality of adjacent multi-sided openings. The outermost sheet on the upstream side of the pad is provided with a plurality of parallel sets of three printed lines formed by oil soluble dye components. The lines flanking each central line in each set are of selected different colors. Each line adjacent to the central line in each set is spaced at a selected distance from the central line to permit the different color dye components to bleed together upon a given loading level of the pad with oil and fat aerosols to form a band having a third different color to visually indicate that the filter pad is in need of replacement.