Patent ID: 7600635

Claim:
A packaged, highly mechanically compressed bale of filter tow comprising: a plurality of layers of filter tow material are layed in successive layers from a lower side to an upper side defining an upper and lower side of an upright said bale of filter tow having a packing density, wherein said bale of filter tow is in block form, and wherein said upper and lower sides are without interfering bulges; said packing density is at least 300 kg/m 3 from said mechanical compression; a resilient elastic packaging material fully enclosing said bale in a mechanically self-supporting manner, wherein said packaging material includes convective joints that are air-tight connections with respect to air convection; said upper side and said lower side are substantially planar wherein the planarity of said upper and lower sides is defined, such that when said lower side of said bale is placed on a horizontal surface, a flat plate can be pressed onto said upper side of said bale by a force of 100N acting in the normal direction on a center of said bale wherein, within the largest rectangle which can be inscribed in a vertical projection of said bale onto the pressed-on plate, at least 90% of the area of said upper side of said bale which is located within the inscribed rectangle is less than 40 mm from the plate; said bale includes a height of at least 900 mm; wherein in said packaged bale a negative pressure from about 0.01 bar to about 0.4 bar relative to an outside pressure is present at least immediately after said bale has been packaged, wherein said packaging material maintains said negative pressure and equalizes pressure gradients at said upper and lower sides, and wherein said negative pressure reduces the pressure which the elastic restoring force of said filter tow material exerts on the packaging from the inside such that a stacking orientation includes a lower side of one said bale is securely stackable directly upon an upper side of another said bale; said stacking orientation of both said bales is the same as the upright orientation of said plurality of layers of filter tow material; and, wherein said air-tight connections include heat sealed seams.