US Patent 6955465 Powder-resistant flexible zipper for reclosable packaging

A flexible zipper intended for use in a package containing powder or other particulate matter. The zipper is designed to be resistant to clogging of the interlocking profiles with powder. This flexible zipper has first and second profiles that interlock in a closed zipper state to define a space therebetween. The space extends in a longitudinal direction, i.e., along the length of the zipper. The bases of both profiles are provided with apertures for enabling powder or other particulate matter trapped in the space between the profiles to pass into the interior volume of a package.