Permeable flexible plastic tubing
Patent 3939875 Issued on February 24, 1976. Estimated Expiration Date: 
February 24, 1993. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
February 24, 1993. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesInventorsAssigneeApplicationNo. 353238 filed on 04/23/1973US Classes:138/178, MISCELLANEOUS138/119, With means for facilitating collapse138/125, Plastic138/137, Distinct layers138/141, Bonded to each other239/145, POROUS OR EXTERNAL WICK DISCHARGE MEANS405/45PorousExaminersPrimary: Queisser, Richard C.Assistant: Yasich, Daniel M. Attorney, Agent or FirmAbstractFlexible tubing, particularly suitable for irrigation purposes, consists of a plurality of superposed, elongated, flexible strips, heat sealed along their longitudinal edges and is substantially flat when empty. At least one of said strips is thermoplastic and at least one has a permeable, fibrous structure and is preferably formed from a non-woven fabric such as spun-bonded polyethylene fiber. | |
