Ethyl cellulose-polyethylene glycol tablet matrix

Claim 1

A SOLID COMPRESSED TABLET HAVING A SLOW PROTRACTED MEDICINAL EFFECT, SAID TABLET CONSISTING OF A MATRIX AND AN ACTIVE INGREDIENT, SAID MATRIX ESSENTIALLY CONSTITUTING A SOLID SOLUTION OF SOLID ETHYL CELLULOSE IN A SOLID MATERIAL SELECTED FROM THE CLASS CONSISTING OF POLYETHYLENE GLYCOL AND WATER-SOLUBLE MONO AND DI FATTY ACID ESTERS THEREOF, SAID ACTIVE INGREDIENT BEING INTIMATELY, FINELY, EXTENSIVELY AND THOROUGHLY DISPERSED THROUGHOUT SAID MATRIX, WHEREBY WHEN THE TABLET IS INGESTED, THE WATER BASED LIQUIDS IN THE ALIMENTARY CANAL WILL FORM A LIQUID-SOLID INTERFACE, WITH THE SURFACE OF THE TABLET, WHEREUPON THE SURFACE OF THE TABLET WILL GRADUALLY BE DISINTERGRATED BY SOLUTION OF THE SOLID MATERIAL SELECTED FROM THE CLASS CONSISTING OF POLYETHYLENE GLYCOL AND WATER-SOLUBLE MONO AND DI FATTY ACID ESTERS THEREOF IN THE ALIMENTARY WATER-BASED LIQUIDS WITH THE CONSEQUENT RELEASE OF THE SOLID ETHYL CELLULOSE AND OF THE ACTIVE INGREDIENT SO THANT THE TABLET WILL SLOWLY DISINTEGRATE AT ITS SURFACE TO SLOWLY AND CONTINUALLY RELEASE THE ACTIVE INGREDIENT AT THE SAID SURFACE INTO THE ALIMENTARY CANAL OVER A PERIOD OF SEVERAL HOURS AND SO THAT BECAUSE THE RATE OF RELEASE OF THE ACTIVE INGREDIENT IS PROPORTIONAL TO THE SURFACE AREA OF THE TABLET AND BECAUSE THE SURFACE AREA OF THE TABLET CONTINUALLY DECREASES IN SIZE THE RATE OF RELEASE OF THE ACTIVE INGREDIENT SLOWLY DECREASES.