Timed-release aspirin

Claim 2

IN A METHOD FOR MAKING AN ASPIRIN TABLET INCLUDING THE STEP OF MIXING UNCOATED PARTICLES OF STANDARD 80 MESH UPS ASPIRIN WITH A SUFFICIENT AMOUNT OF A NON-AQUEOUS SOLUTION, CONTAINING ABOUT 5 TO ABOUT 18 WEIGHT % CELLULOSE ACETATE PHTHALATE, A SUITABLE AMOUNT OF A PHARMACEUTICALLY ACCEPTABLE PLASTICIZER TO PERMIT GRANULES FORMED FROM SAID PARTICLES TO BE PRESSED INTO TABLETS WITHOUT A TABLETING EXCIPIENT, AND A PARMACEUTICALLY ACCEPTABLE SOLVENT, TO COAT AND IMPREGNATE EACH OF THE PARTICLES WITH SAID SOLUTION, FORMING THE RESULTING MIXTURE INTO DISCRETE PLASTICIZED GRANULES LARGER THAN SAID PARTICLES, DRYING SAID PLASTICIZED GRANULES TO REMOVE SUBSTANTIALLY ALL THE SOLVENT THEREFROM, REDUCING SAID DRIED PLASTICIZED GRANULES TO A SIZE WHEREBY THEY CAN PASS THROUGH A 20 MESH SCREEN AND HOMOGENEOUSLY MIXING SAID REDUCED PLASTICIZED GRANULES, THE IMPROVEMENT CONSISTING ESSENTIALLY OF THE STEPS OF PRESSING SAID REDUCED PLASTICIZED GRANULES WITHOUT ANY TABLETING EXCIPIENTS INTO DOSAGE-SIZE TABLETS TO PROVIDE AN ASPIRIN TABLET HAVING TIMED-RELEASE CHARACTERISTICS.

Claim 3

A method according to claim 1 wherein said solvent is selected from the group consisting of acetone, methyl ethyl ketone, methanol, ethanol, isopropanol, methylene chloride, ethylene dichloride, chloroform and mixtures thereof.

Claim 4

A method according to claim 2 wherein said plasticizer is diethylphthalate.

Claim 5

A method according to claim 3 wherein the amount of said diethylphthalate in said solution is about 3 weight%.

Claim 6

A method according to claim 1 wherein the amount of cellulose acetate phthalate contained by each of said granules is about 0.5 to about 5.0% by weight, based on the total weight of the coated granule.

Claim 7

A method according to claim 1 wherein the amount of cellulose acetate phthalate in said solution is about 15 weight%.

Claim 8

In a method for making an aspirin tablet including the steps of mixing uncoated particles of standard 80 mesh USP aspirin with a sufficient amount of a non-aqueous solution, containing about 15 weight% cellulose acetate phthalate, about 3 weight%. diethylphthalate and a pharmaceutically acceptable solvent selected from the group consisting of acetone, methyl ethyl ketone, methanol, ethanol, isopropanol, methylene chloride, ethylene dichloride, chloroform, and mixtures thereof, to coat and impregnate each of said particles with said solution, forming the resultant mixture into discrete plasticized granules larger than said particles, drying said plasticized granules to remove substantially all the solvent therefrom, reducing said dried plasticized granules to a size whereby they can pass through a 20 mesh screen and homogeneously mixing said reduced plasticized granules, the improvement consisting essentially of the steps of pressing said reduced plasticized granules without any tabletting excipients into dosage-size tablets to produce an aspirin tablet having timed-release characteristics.

Claim 9

In a method for making an aspirin tablet including the steps of mixing uncoated particles of standard 80 mesh USP aspirin with a sufficient amount of a non-aqueous solution, containing about 15 weight% cellulose acetate phthalate, about 3 weight%. diethylphthalate and a pharmaceutically acceptable solvent selected from the group consisting of acetone, methyl ethyl ketone, methanol, ethanol, isopropanol, methylene chloride, ethylene dichloride, chloroform, and mixtures thereof, to coat and impregnate each of said particles with said solution, forming the resultant mixture into discrete plasticized granules larger than said particles, drying said plasticized granules to remove substantially all the solvent therefrom, reducing said dried plasticized granules to a size whereby they can pass through a 20 mesh screen and homogeneously mixing said reduced plasticized granules, the improvement consisting essentially of the steps of pressing said reduced plasticized granules without any tabletting excipients into dosage-size tablets to produce an aspirin tablet having timed-release characteristics.