Osmotic membrane and delivery device
US5607696A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 16, 1995 |
| Grant date | Mar 4, 1997 |
| Priority date | — |
| Expiry date | May 16, 2015 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K9/0004
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
The present invention relates to an improvement in an osmotic delivery device wherein the device comprises a semipermeable wall comprising cellulose acetate butyrate and surrounding an internal compartment containing a beneficial agent or medicament formulation, a fluid-activated expandable driving member, optionally a partition layer between the agent formulation and the driving member, and, optionally a density member, and exit means in the semipermeable wall; and wherein the improvement comprises the cellulose acetate butyrate component of the semipermeable wall having a differential scanning calorimetry ("DSC") profile wherein the main or primary DSC peak has a minimum temperature peak above 228.degree. C. and the secondary DSC peak area is equal to or less than about 30% of the total combined areas of the primary and secondary DSC peaks. The invention also relates to the improved semipermeable membrane produced from cellulose acetate butyrate having a differential scanning calorimetry ("DSC") profile wherein the main DSC peak is at a temperature above 228.degree. C. and the secondary DSC peak area is equal to or less than about 30% of the total combined area of the primary and…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.