Hydroxypropyl Methyl Cellulose Hard Capsules and Process of Manufacture
AssigneePfizer Products Inc.
InventorsDominique Nicolas Cade, David He Xinwe
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Abstract
A composition for manufacture of hard hydroxypropyl methyl cellulose capsules comprising a film forming material of hydroxypropyl methyl cellulose having a methoxy content of 27.0-30.0% (w/w), and a hydroxypropoxy content of 4.0-7.5% and as a 2% weight solution, a viscosity of 3.5-6.0 cPs at 20° C., dipping compositions, process for manufacture of hard hydroxypropyl methyl cellulose capsules according to a dip coating process and hard capsule shells.
Claims17
An aqueous composition for manufacture of hard capsules, characterized in that it comprises, in an aqueous solvent, 15-25% by weight, based on the total weight of the aqueous composition, of a hydroxypropyl methyl cellulose (HPMC) having a methoxy content of 27.0-30.0% (w/w), a hydroxypropoxy content of 4.0-7.5% (w/w) and a viscosity of 3.5-6.0 cPs as a 2% weight solution in water at 20° C.
A process for the manufacture of hydroxypropyl methyl cellulose hard capsules according to a dip coating process, characterized in that it comprises the steps of:
- (a) providing an aqueous composition of a hydroxypropyl methyl cellulose having a methoxy content of 27.0-30.0% (w/w), a hydroxypropoxy content of 4.0-7.5% (w/w) and a viscosity of 3.5-6.0 cPs as a 2% weight solution in water at 20° C., wherein the concentration of the hydroxypropyl methyl cellulose in the aqueous composition is chosen to obtain a viscosity of the aqueous composition of 1000 to 3000 cPs measured at a temperature of 10° C. to 1.0° C. below the aqueous composition gelling temperature,
- (b) pre-heating dipping pins so that they are at 55-95° C. when dipped into the aqueous composition,
- (c) dipping the pre-heated dipping pins into the aqueous composition maintained at a temperature of 10° C. to 1.0° C. below its gelling temperature,
- (d) withdrawing the dipping pins from the aqueous composition obtaining a film on the dipping pins and
- (e) drying the film on the dipping pins at a temperature above the gelling temperature of the aqueous composition so as to obtain molded capsule shells on the pins.
A hydroxypropyl methyl cellulose hard capsule shell characterized that it contains a hydroxypropyl methyl cellulose having a methoxy content of 27.0-30.0% (w/w), a hydroxypropoxy content of 4.0-7.5% (w/w) and a viscosity of 3.5-6.0 cPs as a 2% weight solution in water at 20° C.
(canceled)
Dependencies are inferred from the claim text.