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:
Jun. 23, 1981
Filed:
Nov. 19, 1979
Allan J Luck, Harvard, IL (US);
John T Clarke, St. Charles, IL (US);
Michael R Hoffman, Elgin, IL (US);
Masonite Corporation, Chicago, IL (US);
Abstract
A cellulosic fiber containing board is molded at a temperature of at least 525.degree. F. to provide a relatively high density skin on at least one surface. A fibrous composition, including cellulosic fibers, is consolidated to form a consolidated blank. The consolidated blank is then cut to a shape larger in at least two of its three dimensions than corresponding dimensions of a mold cavity when said mold is in a closed position. Urea is then included in at least a surface layer of fibers of the blank in an amount of at least 5% based on the dry weight of the fibers contacted with urea, and thereafter the cut blank is molded to form a contoured product having a skin on at least one surface thereof. The skin is formed by hot-pressing a consolidated cellulosic fiber-containing board including urea in at least its surface fibers, at a temperature of at least 525.degree. F. The composition of the skin has not been determined but is different than the composition of cellulosic material thereunder. In one embodiment, the consolidated cellulosic fiber-containing board has a density of less than 35 pounds/ft..sup.3 to provide a skin of higher density and substantially better structural properties. In accordance with another embodiment, a consolidated board having a density of at least 35 pounds/ft..sup.3 is provided with a skin which is not as significantly different from the core material as is the skin formed over the low density core material of the first embodiment, but the skin on the higher density mats also improves the board strength, stiffness, paint holdout and design fidelity properties.