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National Patent Development Corp

National P
Active Patents
0
Total Holdings
25

Patent Holdings

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Patent No. Title Status Filing Date Grant Date Claims Actions
US4298002A Porous hydrophilic materials, chambers therefrom, and devic… Expired / Lapsed 1979-09-10 1981-11-03 44 Details
US4272518A Plastic wound bandage Expired / Lapsed 1979-07-10 1981-06-09 36 Details
US4121587A Root canal delivery syringe Expired / Lapsed 1977-03-03 1978-10-24 5 Details
US4081402A Hydrophilic absorbents Expired / Lapsed 1975-02-19 1978-03-28 18 Details
US4064086A Thermoplastic hydrogels Expired / Lapsed 1976-07-13 1977-12-20 44 Details
US3941858A Hydrophilic polymers, articles and methods of making same Expired / Lapsed 1973-08-07 1976-03-02 11 Details
US3881026A Powdered water-insoluble polymers containing absorbed addit… Expired / Lapsed 1971-06-14 1975-04-29 6 Details
US3868447A Hema paste Expired / Lapsed 1972-02-02 1975-02-25 19 Details
US3784540A Process of preparing soluble hema-based polymers Expired / Lapsed 1971-10-05 1974-01-08 0 Details
US3695921A Method of coating a catheter Expired / Lapsed 1970-09-09 1972-10-03 0 Details
US3681248A Water soluble entrapping of a fragrance Expired / Lapsed 1970-09-09 1972-08-01 0 Details
US3660563A Water soluble entrapping of a drug Expired / Lapsed 1970-09-09 1972-05-02 0 Details
US3641237A Zero order release constant elution rate drug dosage Expired / Lapsed 1970-09-30 1972-02-08 0 Details
US3632416A Fibrous textile materials impregnated with hydroxyalkyl met… Expired / Lapsed 1967-10-27 1972-01-04 7 Details
US3618213A Denture liners Expired / Lapsed 1970-04-27 1971-11-09 0 Details
US3612348A Pill dispenser with disposable magazine and indicia Expired / Lapsed 1969-11-17 1971-10-12 11 Details
US3577512A Sustained release tablets Expired / Lapsed 1968-10-11 1971-05-04 0 Details
US3576760A Water soluble entrapping Expired / Lapsed 1969-06-13 1971-04-27 0 Details
US3566874A Catheter Expired / Lapsed 1968-08-13 1971-03-02 13 Details
US3520949A Hydrophilic polymers,articles and methods of making same Expired / Lapsed 1966-07-26 1970-07-21 0 Details
US3515579A Non-fogging transparent material Expired / Lapsed 1969-02-26 1970-06-02 0 Details
US3428043A Bandage containing absorbed therapeutic materials Expired / Lapsed 1966-06-09 1969-02-18 0 Details
US3400890A Fragrance releasing device Expired / Lapsed 1966-12-07 1968-09-10 0 Details
US3311229A Tablet package Expired / Lapsed 1965-01-21 1967-03-28 2 Details
US3255753A Electrical sleep machine and sleep inducing method Expired / Lapsed 1963-03-22 1966-06-14 2 Details