US4017647A
Expired / Lapsed
US
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Method for providing enteric coatings on solid dosage forms
Assignee: Shin-Etsu Chemical Co Ltd
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Filing: 1975-06-09
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Granted: 1977-04-12
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Expires: 1995-06-09
Abstract
Abstract Enteric coatings are provided on solid pharmaceutical dosage forms by a method comprising covering the dosage froms with an aqueous solution of a polymeric substance having carboxyl groups in the watersoluble salt form and contacting the thus coated dosage forms with an inorganic acid to convert the polymeric substance into the water-insoluble acid form. The coating solution includes no organic solvent, and this method is safe from dangers of fires or explosions and air pollution.
Inventors
- 👤 Shigeru Ohno
- 👤 Noboru Hoshi
- 👤 Fujio Sekigawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:05
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/20; A61K9/28; A61K9/2806; A61K9/2833; A61K9/286; A61K9/2866; A61K9/2893; A61K9/48; A61K9/50; A61K9/5005; A61K9/5021; A61K9/5036; A61K9/5042
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
104 words
A method for providing an enteric coating on a solid pharmaceutical dosage form which comprises coating said dosage form with an aqueous solution of a polymeric substance having carboxyl groups in the form of a water-soluble salt selected from the group consisting of alkali metal, ammonium and amine salts of said polymeric substance said coating being carried out in the absence of an organic solvent and bringing the coated dosage form into contact with a strong inorganic acid so that said polymeric substance is converted into a water-insoluble acid form, the amount of said acid being equal to or greater than the equivalent amount
Claim 2
Independent Claim
104 words
A method for providing an enteric coating on a solid pharmaceutical dosage form which comprises coating said dosage form with an aqueous solution of a polymeric substance having carboxyl groups in the form of a water-soluble salt selected from the group consisting of alkali metal, ammonium and amine salts of said polymeric substance said coating being carried out in the absence of an organic solvent and bringing the coated dosage form into contact with a strong inorganic acid so that said polymeric substance is converted into a water-insoluble acid form, the amount of said acid being equal to or greater than the equivalent amount
Claim 3
Dependent Claim
36 words
The method as claimed in claim 1 wherein said polymeric substance is a partial ester of at least one cellulose derivative selected from the class consisting of cellulose ethers and cellulose esters with at least one
Claim 4
Dependent Claim
48 words
The method as claimed in claim 1 wherein said polymeric substance is selected from the class consisting of partial esters of at least one vinyl polymer or copolymer containing vinyl alcohol units in its molecules with at least one polybasic acid and polymers or copolymers of vinyl monomers
Claim 5
Dependent Claim
35 words
The method as claimed in claim 2 wherein said cellulose ether is selected from the class consisting of methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxyethyl methyl cellulose, hydroxyethyl ethyl cellulose, and hydroxypropyl methyl
Claim 6
Dependent Claim
22 words
The method as claimed in claim 2 wherein said cellulose ester is selected from the class consisting of cellulose acetate and cellulose
Claim 7
Dependent Claim
31 words
The method as claimed in claim 2 wherein said polybasic acid is selected from the class consisting of succinic acid, maleic acid, phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, trimellitic acid, and
Claim 8
Dependent Claim
12 words
The method as claimed in claim 1 wherein said inorganic acid is
Claim 9
Dependent Claim
13 words
The method as claimed in claim 7 wherein said hydrochloric acid is in
Claim 10
Dependent Claim
13 words
The method as claimed in claim 2 wherein said partial ester is cellulose
Claim 11
Dependent Claim
12 words
The method as claimed in claim 2 wherein said partial ester is
Claim 12
Dependent Claim
13 words
The method as claimed in claim 1 wherein said coating layer has a
Claim 13
Independent Claim
93 words
A method for providing an enteric coating on a solid pharmaceutical dosage form which comprises coating said solid dosage form with an aqueous solution of cellulose acetate phthalate in a water-soluble sodium salt form in the absence of organic solvent to form a layer of from 0.01 to 0.5 mm thick and bringing the coated dosage form into contact with hydrochloric acid in an amount in excess over the equivalent of said sodium salt of cellulose acetate phthalate whereby said sodium salt of cellulose acetate phthalate is converted into a water-insoluble acid form.
Claim 14
Independent Claim
93 words
A method for providing an enteric coating on a solid pharmaceutical dosage form which comprises coating said solid dosage form with an aqueous solution of cellulose acetate phthalate in a water-soluble sodium salt form in the absence of organic solvent to form a layer of from 0.01 to 0.5 mm thick and bringing the coated dosage form into contact with hydrochloric acid in an amount in excess over the equivalent of said sodium salt of cellulose acetate phthalate whereby said sodium salt of cellulose acetate phthalate is converted into a water-insoluble acid form.
Claim 15
Independent Claim
97 words
A method for providing an enteric coating on a solid pharmaceutical dosage form which comprises coating said solid dosage form with an aqueous solutin of hydroxypropyl methyl cellulose phthalate in a water-soluble sodium salt form in the absence of an organic solvent to form a layer of from 0.01 to 0.5 mm thick and brining the coated dosage form into contact with hydrochloric acid in an amount in excess over the equivalent to said sodium salt of hydroxypropyl methyl cellulose phthalate whereby said sodium salt of hydroxypropyl methyl cellulose phthalate is converted into a water-insoluble acid form.
Claim 16
Independent Claim
97 words
A method for providing an enteric coating on a solid pharmaceutical dosage form which comprises coating said solid dosage form with an aqueous solutin of hydroxypropyl methyl cellulose phthalate in a water-soluble sodium salt form in the absence of an organic solvent to form a layer of from 0.01 to 0.5 mm thick and brining the coated dosage form into contact with hydrochloric acid in an amount in excess over the equivalent to said sodium salt of hydroxypropyl methyl cellulose phthalate whereby said sodium salt of hydroxypropyl methyl cellulose phthalate is converted into a water-insoluble acid form.
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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) | 1980-04-11 | 1980-10-11 | 1981-04-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-04-11 | 1984-10-11 | 1985-04-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-04-11 | 1988-10-11 | 1989-04-12 | $7700.00 | Window Closed / Lapsed |