US4462839A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Enteric coating for pharmaceutical dosage forms
Assignee: FMC Corp
•
Filing: 1983-06-16
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Granted: 1984-07-31
•
Expires: 2003-06-16
Abstract
Abstract The application discloses a process for making a polymeric powder which is readily dispersible in water to provide a composition useful for forming an enteric coating on pharmaceutical dosage forms and also a process for using the powder for its intended purpose.
Inventors
- 👤 Emanuel J. McGinley
- 👤 Domingo C. Tuason, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:39
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/20; A61K9/28; A61K9/2806; A61K9/2833; A61K9/286; A61K9/2866
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
69 words
A process of making a polymeric powder which is readily dispersible in water to provide a composition useful for forming an entric coating on pharmaceutical dosage forms, comprising providing a freshly prepared aqueous dispersion of spherical water-insoluble enteric polymer particles, adding to said dispersion a phosphate salt in an amount sufficient to minimize coalescense of the particles during spray drying, thoroughly mixing, and spray drying to form the powder.
Claim 2
Dependent Claim
69 words
A process of making a polymeric powder which is readily dispersible in water to provide a composition useful for forming an entric coating on pharmaceutical dosage forms, comprising providing a freshly prepared aqueous dispersion of spherical water-insoluble enteric polymer particles, adding to said dispersion a phosphate salt in an amount sufficient to minimize coalescense of the particles during spray drying, thoroughly mixing, and spray drying to form the powder.
Claim 3
Dependent Claim
20 words
The process set forth in claim 1 wherein the phosphate salt is either trisodium phosphate, tripotassium phosphate or triammonium phosphate.
Claim 4
Dependent Claim
33 words
The process set forth in claim 1 wherein the phosphate salt is added in an amount of between about 1.4% and about 7.3% based upon the weight of the dry insoluble polymer particles.
Claim 5
Dependent Claim
33 words
The process set forth in claim 1 wherein the phosphate salt is added in an amount of between about 2.0% and about 4.5% based upon the weight of the dry insoluble polymer particles.
Claim 6
Dependent Claim
18 words
The process set forth in claim 1 wherein said polymer particles predominantly have a diameter below 5.0 μm.
Claim 7
Dependent Claim
21 words
The process set forth in claim 5 wherein said polymer particles predominantly have a diameter between about 0.2 and 0.5 μm.
Claim 8
Dependent Claim
37 words
The process set forth in claim 6 wherein the spray dried powder consists of aggregates of particles capable of being reconstituted to near the original size of the solid particles contained in the freshly prepared aqueous dispersion.
Claim 9
Dependent Claim
49 words
The process set forth in claim 7 comprising the additional steps of dispersing the spray dried powder in water, adding a plasticizer in an amount of between 10% and 40% of the weight of the dry polymer to form a coating composition, and coating a pharmaceutical dosage form therewith.
Claim 10
Dependent Claim
10 words
A polymeric powder made by the process of claim 1.
Claim 11
Dependent Claim
68 words
A process of making a polymeric powder which is readily dispersible in water to provide a composition useful for forming an enteric coating on pharmaceutical dosage forms, comprising providing a freshly prepared aqueous dispersion of cellulose acetate phthalate particles, adding to said dispersion a phosphate salt in an amount sufficient to minimize coalescense of the particles during spray drying, thoroughly mixing, and spray drying to form the powder.
Claim 12
Dependent Claim
68 words
A process of making a polymeric powder which is readily dispersible in water to provide a composition useful for forming an enteric coating on pharmaceutical dosage forms, comprising providing a freshly prepared aqueous dispersion of cellulose acetate phthalate particles, adding to said dispersion a phosphate salt in an amount sufficient to minimize coalescense of the particles during spray drying, thoroughly mixing, and spray drying to form the powder.
Claim 13
Dependent Claim
20 words
The process set forth in claim 10 wherein the phosphate salt is either trisodium phosphate, tripotassium phosphate or triammonium phosphate.
Claim 14
Dependent Claim
34 words
The process set forth in claim 10 wherein the phosphate salt is added in an amount of between about 1.4% and about 7.3% based upon the weight of the dry cellulose acetate phthalate particles.
Claim 15
Dependent Claim
34 words
The process set forth in claim 10 wherein the phosphate salt is added in an amount of between about 2.0% and about 4.5% based upon the weight of the dry cellulose acetate phthalate particles.
Claim 16
Dependent Claim
23 words
The process set forth in claim 10 wherein said cellulose acetate phthalate particles are spherical and predominantly have a diameter below 5.0 μm.
Claim 17
Dependent Claim
23 words
The process set forth in claim 14 wherein said cellulose acetate phthalate particles predominantly have a diameter between about 0.2 and 0.5 μm.
Claim 18
Dependent Claim
37 words
The process set forth in claim 15 wherein the spray dried powder consists of aggregates of particles capable of being reconstituted to near the original size of the solid particles contained in the freshly prepared aqueous dispersion.
Claim 19
Dependent Claim
51 words
The process set forth in claim 16 comprising the additional steps of dispersing the spray dried powder in water, adding a plasticizer in an amount of between 10% and 40% of the weight of the cellulose acetate phthalate particles to form a coating composition, and coating a pharmaceutical dosage form therewith.
Claim 20
Dependent Claim
10 words
A polywmeric powder made by the process of claim 10.
Claim 21
Dependent Claim
60 words
A polymeric powder capable of being readily dispersed in water to provide with the addition of a plasticizer a composition useful for forming an enteric coating on pharmaceutical dosage forms, said powder consisting essentially of spherical water-insoluble enteric polymer particles, said enteric polymer particles having a water-insoluble core of such polymer and a water soluble surface portion of such polymer.
Claim 22
Dependent Claim
60 words
A polymeric powder capable of being readily dispersed in water to provide with the addition of a plasticizer a composition useful for forming an enteric coating on pharmaceutical dosage forms, said powder consisting essentially of spherical water-insoluble enteric polymer particles, said enteric polymer particles having a water-insoluble core of such polymer and a water soluble surface portion of such polymer.
Claim 23
Dependent Claim
14 words
The powder set forth in claim 19 wherein said polymer is cellulose acetate phthalate.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-07-31 | 1988-01-30 | 1988-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-07-31 | 1992-01-30 | 1992-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-07-31 | 1996-01-30 | 1996-07-31 | $7700.00 | Window Closed / Lapsed |