Collapsible hollow articles with improved latching and dispensing configurations

Abstract From the Canadian patent

Abstract, Hollow articles such as plastic bottles and tubes having a portion of the sidewall including latching bellows, are formed with modified inner and outer fold rings to reduce the angular flexure between unfolded and folded (latched) bellow walls. The bellow walls are modified by reducing the slope of the walls as they approach the inner fold rings to thereby reduce the unfolded (unflexed) angle between the walls at the inner fold rings. The modified geometry permits better utilization of high density linear polymer plastics by lessening or preventing the "crystalline" fracturing and lamination at the inner fold ring with the first latching of the bellows. The bottle material is …