Patent ID: 7175583
Filing Date: 2007-02-13
Classification: B31B,B65D

Abstract:
1. A method of making a square bottomed plastic bag stack, comprising the steps of: extruding a tube of polyethylene material; forming side gussets in said tube and flattening same; cutting said flattened tube perpendicular to said side gussets to a first predetermined length, thereby forming a bag blank, said bag blank having front and rear walls, front and rear top edges, front and rear bottom edges, first and second side edges; slitting said bag blank at intersections of said side gussets and said front and rear walls from said front and rear bottom edges upwardly for a first predetermined distance; folding lower corners of said each side gusset outwardly and together to form downward pointing triangular panels; folding said triangular panels inwardly from said side gussets; folding lower portions of said front and rear walls inwardly; sealing said front and rear wall together adjacent said front and rear bottom edges to form a bag bottom; sealing said bag bottom to said side gussets adjacent upper edges of said triangular panels; sealing said triangular panels to an upper surface of said bag bottom; folding each of said bags inwardly at said side gussets and upwardly from either of said front wall and said rear wall at a point spaced upwardly from said bottom edge, to form a flattened bag; and stacking a plurality of said bag blanks in registration to form a bag stack.