US4113816A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the manufacture of layered tablets incorporating controlled-release microcapsules
Assignee: Choay SA
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Filing: 1977-02-11
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Granted: 1978-09-12
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Expires: 1997-02-11
Abstract
Abstract The present invention relates to the manufacture of new tablets for administration of medicaments, which tablets contain in their mass, controlled-release microcapsules, that is to say elemental particles coated with a protective covering which contains an encapsulated product which is gradually released in a controlled, regular and time-dependent way.
Inventors
- 👤 Yvette Fr. M. J. Estevenel
- 👤 Maurice H. Thely
- 👤 Wladimir A. Coulon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 09:53
CPC Classifications
A; A61; A61J; A61J3/00; A61J3/07; A61K; A61K9/00; A61K9/20; A61K9/2072; A61K9/2077; A61K9/2081
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
137 words
A process of making layered tablets having upper and lower surfaces and a peripheral surface and incorporating controlled-release microcapsules, comprising: (a) depositing in a tablet-making machine a bottom external layer comprising essentially excipients in granular form and levelling the upper surface of said layer by a tamping action; (b) depositing on said levelled layer a superposed layer comprising microcapsules containing a pharmaceutically active substance, and similarly levelling said microcapsule layer; (c) depositing on said levelled microcapsule layer a superposed top external layer comprising excipients in granular form; and (d) then compressing said superposed layers by a force sufficient to bond the granules and microcapsules without crushing the latter to produce tablets having a hardness of about 10 to 20 kg on the said upper and lower surfaces and about 8 to 15 kg on the peripheral surface.
Claim 2
Dependent Claim
137 words
A process of making layered tablets having upper and lower surfaces and a peripheral surface and incorporating controlled-release microcapsules, comprising: (a) depositing in a tablet-making machine a bottom external layer comprising essentially excipients in granular form and levelling the upper surface of said layer by a tamping action; (b) depositing on said levelled layer a superposed layer comprising microcapsules containing a pharmaceutically active substance, and similarly levelling said microcapsule layer; (c) depositing on said levelled microcapsule layer a superposed top external layer comprising excipients in granular form; and (d) then compressing said superposed layers by a force sufficient to bond the granules and microcapsules without crushing the latter to produce tablets having a hardness of about 10 to 20 kg on the said upper and lower surfaces and about 8 to 15 kg on the peripheral surface.
Claim 3
Dependent Claim
14 words
A process according to claim 1, wherein the external layers also contain active substances.
Claim 4
Dependent Claim
13 words
A process according to claim 1, wherein the external layers are identical compositions.
Claim 5
Dependent Claim
17 words
A process according to claim 1, wherein the external layers are of different composition from each other.
Claim 6
Dependent Claim
34 words
A process according to claim 1, wherein the ratio between the sum of the thicknesses of the external layers and the thickness of the internal layer containing the microcapsules is between 0.8 and 4.
Claim 7
Dependent Claim
34 words
A process according to claim 1, wherein the ratio between the sum of the thicknesses of the external layers and the thickness of the internal layer containing the microcapsules is between 1 and 2.4.
Claim 8
Dependent Claim
33 words
A process according to claim 1, wherein said microcapsules containing a pharmaceutically active substance are associated in the internal layer with an excipient which causes the disintegration of the microcapsules on subsequent administration.
Claim 9
Dependent Claim
40 words
A process according to claim 1 wherein said excipients are chosen from a group consisting of microcrystalline cellulose, starch, alginate and polyoxyethylene-glycol and said external layers are in the form of granules having the same grain size as said microcapsules.
Claim 10
Dependent Claim
65 words
A process according to claim 1 in which the granular excipients are selected from the group consisting of lubricants, fillers and mixtures thereof, and the respective thicknesses of the external layers and the internal layer being such that the ratio between the sum of the thicknesses of the external layers and the thickness of the internal layer containing the microcapsules is between 0.8 and 4.0.
References Cited (Backward Citations)
US3096248A
Cited
US3723589A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-09-11 | 1982-03-13 | 1982-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-09-11 | 1986-03-13 | 1986-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-09-11 | 1990-03-13 | 1990-09-12 | $7700.00 | Window Closed / Lapsed |