Separable fastener and article for making same

An elongate strip material which may be severed into at least two lengths to form a fastener, comprising:

• a backing comprising a uniform nonfibrous nonoriented polymeric surface bonding layer of a predetermined thickness and having an exposed major surface;
• and
• a multiplicity of flexible resilient generally U-shaped monofilaments of longitudinally oriented polymeric material of a diameter less than said predetermined thickness, each including:
• a central bight portion embedded in, bonded in, and held only by said bonding layer;
• two straight stem portions of essentially the same length extending from the opposite ends of said bight portion, projecting generally normal to said exposed major surface of the surface bonding layer, and having unsupported ends opposite said bight portion;
• and
• an enlarged generally circular head at each unsupported end, each of the heads being generally concentric with its supporting stem portion, having a cam surface opposite its supporting stem portion adapted for engagement with the cam surfaces of heads along a different portion of the strip material to produce deflection of the stem and movement of the heads on the stems past each other upon movement of the heads toward each other with the portions of the backing behind the heads generally parallel, and having a surface opposite said cam surface which is generally planar and extends at generally a right angle radially from its supporting stem portion adapted to engage a similar surface on another head;
• the bight portions of said U-shaped monofilaments being disposed generally parallel with a plurality of groups of the bight portions each being disposed generally side by side to form a plurality of generally parallel rows of stem portions with said heads along and between the rows being spaced at distances which, as an average, are generally no greater than the diameter of the heads so that simultaneous movement of all the heads of different portions of the strip material past each other can occur only upon resilient separation of many of said heads;
• with said stems being spaced apart a distance which, as an average, is at least as large as the diameter of said heads to afford positioning of the heads of one portion of the strip material between the stems of another portion of the strip material;
• and with the length of each stem portion from the major surface to the head on its unsupported end being at least equal to the diameter of the head to afford deflection of the stems to allow simultaneous movement of all the heads of different portions of the strip material past each other at any relative angular orientation between the rows of stems of the portions.