Patent ID: 7744922

Claim:
A method of preparing a rapidly water-soluble hard capsule having a core comprising one or more core components, and a water-soluble envelope comprising 6.5 to 15% by weight of a film-forming polymer of gelatin, 0.8 to 1.5% by weight sorbitol, and either 0.01 to 0.2% by weight fumaric acid or about 0.5% by weight citric acid, wherein the capsule has a hardness of 1 to 5 Kg/cm 2 and the envelope of the capsule exhibits a total solubilization time of less than or equal to 85 seconds, using a dissolving device wherein the capsule is crossed by an aqueous flow maintained at 37±0.5° C., pH 6.5, 50 ml/min, said method comprising the steps of: providing a liquid mixture of core components, providing a liquid mixture of envelope components comprising a film forming polymer, a plasticizer, and an acid, co-extruding the liquid mixture of core components and liquid mixture of envelope components into an oily organic solvent to form the capsule having an envelope and a core therein, centrifuging the capsules to remove said oily organic solvent, immersing the capsule in an anhydrous organic solvent wherein the temperature of said anhydrous organic solvent is 0° C. to 25° C., and drying the capsule, provided that the method does not include a step of immersing the capsule in an organic liquid or an emulsion that contains a crosslinking agent.