United States Patent (19) 11) 4,277,428 Luck Et Al
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United States Patent (19) 11) 4,277,428 Luck et al. (45) : Jul. 7, 1981 (54) POST-PRESS MOLDING OF MAN-MADE (56) References Cited BOARDS TO PRODUCE CONTOURED FURNTURE PARTS U.S. PATENT DOCUMENTS (75) Inventors: Allan J. Luck, Harvard; John T. 4,175,106 11/1979 Lucket al. ........................... 264/18 Clarke; Roger F. Sutton, both of St. Primary Examiner-Donald E. Czaja Charles, all of Ill. Assistant Examiner-James R. Hall Attorney, Agent, or Firm-Mason, Kolehmainen, (73) Assignee: Masonite Corporation, Chicago, Ill. Rathburn & Wyss Notice: The portion of the term of this patent (57) ABSTRACT subsequent to Nov. 20, 1996, has Multi-sided decorative moldings and furniture parts are been disclaimed. manufactured by drying or hot-pressing a cellulosic 21 Appl. No.: 95,627 fiber-containing mat to consolidate said mat into a uni tary blank, cutting the blank to a size larger than inte 22 Filed: Nov. 19, 1979 rior dimensions of a closed mold in each of its three dimensions and with at least two generally shaped or Related U.S. Application Data profiled edge surfaces disposed between a top surface (63) Continuation-in-part of Ser. No. 833,037, Sep. 14, 1977, and a bottom surface of the blank. The cut blank is then Pat. No. 4, 175,106. molded at a temperature of at least 200' F. for a period of time sufficient to permanently transfer the interior 51 Int. C. ................................................ B29J S/00 shape and design of the mold cavity to every surface of 52 U.S. C. .................................... 264/118; 264/119; the blank. 264/120; 264/320 (58) Field of Search ................ 264/119, 118, 120, 320 16 Claims, 5 Drawing Figures 4,277,428 2 dimensions of the consolidated fiberboard along its POST-PRESS MOLDING OF MAN-MADE BOARDS length, width and height to form a multi-sided con TO PRODUCE CONTOURED FURNITURE PARTS toured board having dimensions corresponding to the dimensions of the mold cavity. It is quite surprising that CROSS REFERENCE TO RELATED 5 a "post-press molding' operation is effective in substan APPLICATIONS tially altering the dimensions of a consolidated fiber This application is a continuation-in-part of Ser. No. board in all three dimensions to produce a multi-sided 833,037 filed Sept. 14, 1977, now U.S. Pat. No. embossed part without visible fiber tearing or delamina 4, 175,106. tion. O 2. Description of the Prior Art BACKGROUND OF THE INVENTION It is very difficult to both densify and restructure the 1. Field of the Invention surface of a consolidated fiberboard without destroying The present invention relates to a method of molding the fiber-to-fiber surface welds referred to in this assign man-made boards to produce contoured furniture parts. ee's U.S. Pat. No. 4,007,076 and co-pending application More particularly, the present invention relates to a 15 Ser. No. 739,184 filed Nov. 5, 1976, now U.S. Pat. No. method of molding a man-made board to produce con 4,175,150. toured furniture or decorative parts, such as a drawer An article entitled "Wood Embossing Machines Cut front, cabinet door, table top, and the like. A fiberboard Product Steps For "Carved' Parts” by Bruce Scully, or particle board blank is first formed and cut to a size appearing in Furniture Design & Manufacturing, Feb slightly larger than interior dimensions of a mold. The 20 ruary, 1977, pages 30–33 and an article entitled "Two cut blank can be pre-treated with a sealer, preferably New Concepts in Embossing” by Darrell Ward, ap including a release agent, and is then molded at a tem pearing in Woodworking & Furniture Digest, June, perature of at least 200 F. to form the blank into its final 1977, pages 46-50, relate to embossing materials, includ shape. ing fiberboard, in making furniture parts, but do not The process of the present invention relates to a 25 suggest molding a man-made board to produce multi "post-press" or after consolidation molding operation for molding a fiberboard or particle board into a furni sided furniture or decorative parts as disclosed herein. ture part or decorative part having a desired shape. The SUMMARY OF THE INVENTION fiberboard or particle board substrate is formed by de An object of the present invention is to provide a positing a mass of fibers onto a support member, by 30 either a dry deposition process or wet deposition pro method of making decorative articles or furniture parts cess known in the art of papermaking or fiberboard from man-made boards having the look, feel and sound manufacture, and then consolidating the fibers by dry of natural wood. ing or under test and pressure. Typical products made Another object of the present invention is to provide by these processes are insulation board, medium density 35 a method of making a cellulosic fiber-containing fiberboard and particle board. molded furniture part or decorative molding having the The consolidated mat is first manufactured by consol look, feel, and texture of natural wood or other natural idating a cellulosic fiber-containing composition to or decorative materials by compressing a consolidated form a consolidated fiberboard or particle board. The man-made board in all three of its dimensions in a mold consolidated mat can be consolidated by drying a mat at a temperature of at least 200 F. formed by depositing a water slurry of fibers onto a Another object of the present invention is to provide water pervious support member, as is common in the a method of making a man-made molded board having manufacture of insulation board, or the mat can be con design fidelity and paint holdout properties equal to or solidated under heat and pressure until substantially dry better than hardboards and natural wood parts manu in a first press operation. The consolidated mat is there 45 factured in accordance with existing technology. after "post-pressed" in a mold having the desired con Another object of the present invention is to provide figuration to form the consolidated fiberboard into a a method of molding consolidated man-made board desired shape and to impart surface texture if desired. blanks having a density of at least 10 pounds/ft. at a After board consolidation, the blank is cut from the temperature in the range of 200-650 F. board to a size slightly larger than interior dimensions 50 Another object of the present invention is to provide of a mold cavity. The consolidated cut blank is thereaf a method of molding consolidated man-made board ter "post-press molded" in a mold having a desired blanks having a density of at least 10 pounds/ft. at a internal configuration to mold the consolidated fiber temperature in the range of 250-650 F. board blank into a multi-sided part having a desired In accordance with an important feature of the pres shape and to form a surface design corresponding to 55 ent invention, the technology disclosed herein has been natural wood or other decorative materials, such as developed to provide a strong cellulosic fiber-contain cork, slate and the like. For the purpose of the present ing molded product, for example, molded insulation invention, a "post-press molding' operation refers to a board or particle board which has sufficient strength for molding step performed on a consolidated man-made end uses such as furniture parts and decorative mold board which changes the dimensions of the consoli ings. The product is produced by first manufacturing dated board in all three of its dimensions, and consolidating a fiberboard or particle board blank, The fiberboard of the present invention is generally then cutting the blank to a size slightly larger than inte formed in two separate operations. The first operation rior dimensions of a mold cavity; thereafter, the consoli forms a consolidated man-made board of any desired dated, oversized blank is molded to size and shape. If density, i.e., 10-65 pounds/ft., in a manner common in 65 the blank is manufactured having a density greater than the art of forming a fiberboard, such as insulation board 35 pounds/ft.3, the final product will be very high or medium density hardboard. The second step com strength as disclosed in our prior U.S. Pat. No. prises "post-press molding' which changes the overall 4,175,106. It has been found herein that lower tempera 4,277,428 5 6 FIG. 3 is a cross-sectional, perspective view of an sion, and oversized to the mold length and width by oversized, shaped, pre-mold blank which is molded, as about 1/16'. shown in FIGS. 4 and 5 to produce the part shown in A mold lubricant or sealer can be applied to the sur F.G. 2. faces of the blank prior to molding. The sealer aids in FIG. 4 is a cross-sectional view of the oversized blank hardening the molded surfaces, increasing paint hold as it is forced into the mold along tapered edges. out, and can include a releasing agent such as polydi FIG. 5 is a cross-sectional view of the closed mold methylsiloxane to aid in removing the finished part during molding of the blank of FIG. 3 and shows the from the mold. Typical mold lubricants are, for exam pre-molded shape of the blank in broken lines. ple, acrylic polymers, such as Lilly Prepress Sealer O 73-035, and the like. Any lubricant, sealer or releasing DETAILED DESCRIPTION OF THE agent can be applied to the oversized blank prior to INVENTION molding so long as the additive can withstand the high The man-made blank is manufactured in accordance molding temperature.