Direct filling pressurized writing instrument and method of manufacturing

Abstract From the Canadian patent

Abstract of the Disclosure, A shell formed of plastics material of a type which is highly impermeable to solvents found in certain ink compositions forms the body of a pen. A follower and wiping element is placed in the bore of the shell through its rear end opening and a charge of ink is introduced into the shell through its forward ball point assembly receiving opening. A ball point assembly is then snap fitted into this opening. The bore of the shell rearwardly of the follower is pressurized substantially above atmospheric pressure and then closed under such pressure by the insertion in the rear end portion of the bore of a closure plug which is secured and sealed by spin welding.