Abstract An article or plurality of articles are supported in a mold, usually covered with film or a liquid release. Plastic is foamed up, over and around this in the mold. The resulting package is removed from the mold. It is not damaged by the air or water or most solvents and the contents of the package are protected from the deteriorating effect of air and moisture. A tear strip may be incorporated in the foam-preferably at about the middle-to facilitate subsequent removal of foam from the article. A boss and depression of about the same area and shape may be formed on opposite sides of the package (usually the top and bottom) to facilitate stacking for storage. A trademark may be molded in the foam surface.
THE METHOD OF FORMING A FOAM PACKAGE WHICH COMPRISES SUPPORTING A PIECE OF FILM ON A SUPPORT IN A MOLD, PLACING THE ARTICLE TO BE PACKED ON THE FILM ABOVE THE SUPPORT, COVERING THE TOP AND SIDES OF THE ARTICLE WITH ANOTHER PIECE OF FILM, THE PIECES OF FILM BEING LARGE ENOUGH TO OVERLAP AT THE SIDES OF THE ARTICLE, INTRODUCING INTO THE MOLD (A) SUFFICIENT POLYURETHANE PRECURSOR OF THE CLASS CONSISTING OF POLYESTERS AND POLYETHERS, (B) AN EXCESS OF POLYISOCYANATE, AND (C) FOAMING AGENT IN THE PROPORTIONS TO PRODUCE A FOAM AND ALLOWING THE MIXTURE TO FOAM AND COMPLETELY ENCLOSE THE ARTICLE, WHEREBY THE RISING FOAMING MIXTURE LIFTS THE OUTER PORTION OF THE LOWER PIECE OF FILM AND CLOSES IT AGAINST THE PORTIONS OF THE UPPER PIECE WHICH ARE AT THE SIDES OF THE ARTICLE AND FILLS THE MOLD TO SURROUND THE ARTICLE, AND THEN REMOVING THE FOAM PACKAGE FROM THE MOLD.
Claim 2
Independent Claim
153 words
THE METHOD OF FORMING A FOAM PACKAGE WHICH COMPRISES SUPPORTING A PIECE OF FILM ON A SUPPORT IN A MOLD, PLACING THE ARTICLE TO BE PACKED ON THE FILM ABOVE THE SUPPORT, COVERING THE TOP AND SIDES OF THE ARTICLE WITH ANOTHER PIECE OF FILM, THE PIECES OF FILM BEING LARGE ENOUGH TO OVERLAP AT THE SIDES OF THE ARTICLE, INTRODUCING INTO THE MOLD (A) SUFFICIENT POLYURETHANE PRECURSOR OF THE CLASS CONSISTING OF POLYESTERS AND POLYETHERS, (B) AN EXCESS OF POLYISOCYANATE, AND (C) FOAMING AGENT IN THE PROPORTIONS TO PRODUCE A FOAM AND ALLOWING THE MIXTURE TO FOAM AND COMPLETELY ENCLOSE THE ARTICLE, WHEREBY THE RISING FOAMING MIXTURE LIFTS THE OUTER PORTION OF THE LOWER PIECE OF FILM AND CLOSES IT AGAINST THE PORTIONS OF THE UPPER PIECE WHICH ARE AT THE SIDES OF THE ARTICLE AND FILLS THE MOLD TO SURROUND THE ARTICLE, AND THEN REMOVING THE FOAM PACKAGE FROM THE MOLD.