Controlled release means
Patent 4975284 Issued on December 4, 1990. Estimated Expiration Date: 
July 19, 2008. 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.
July 19, 2008. 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 ReferencesRate controlled dispenser for administering beneficial agent Lipid osmotic pump Pharmaceutical delivery system Pseudoephedrine dosage form Patent #: 4801461 InventorsAssigneeApplicationNo. 221316 filed on 07/19/1988US Classes:424/497, Containing solid synthetic polymers424/494Cellulose derivativesExaminersPrimary: Page, Thurman K.Attorney, Agent or FirmInternational ClassA61K 009/22Foreign Application Priority Data1987-07-21 GBAbstractA controlled release means comprisng a core of at least one water-soluble ingredient of which at least one ingredient is to be released in a controlled manner, said core being surrounded by a semi-permeable membrane coating containing dispersed water-soluble pore-forming particles in sufficient amount to give rise to dissolution upon exposure to an aqueous environment to form only one or two pores extending through the coating to provide communication between the core and the exterior of the coating and a method of making the same. | |
