Laminar structure for administering a chemical at a controlled release rate
Patent 4931281 Issued on June 5, 1990. Estimated Expiration Date: 
March 10, 2009. 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.
March 10, 2009. 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 ReferencesPolymeric diffusion matrix containing a vasodilator Penetrating topical pharmaceutical compositions containing 1-dodecyl-azacycloheptan-2-one Patent #: 4557934 InventorsAssigneeApplicationNo. 322605 filed on 03/10/1989US Classes:424/448, Pressure sensitive adhesive means424/447, Bandages with incorporated medicaments424/449Transdermal or percutaneousExaminersPrimary: Robinson, Ellis P.Assistant: Prater, P. L. Attorney, Agent or FirmInternational ClassA61F 013/02AbstractA laminar structure for administering a chemical at a controlled release rate is disclosed. The structure comprises a backing member which acts as a boundary through which the chemical does not pass. Contacting at least a portion of the backing member is a chemical containing layer having therein a first chemical portion and a second chemical portion. The first and second chemical portions comprise a mixture of chemical in a first concentration transport mode and a second concentration transport mode. The mixture being in a ratio to give a desired chemical release rate from the chemical containing layer. | |
