GB1485659A - Disintegrating agent for tablets - Google Patents

Abstract

1485659 Disintegrating agent for tablets DOW CHEMICAL CO 27 Nov 1975 48733/75 Headings A5B and A5E A disintegrating agent for tablets (defined as being a compressed or moulded mass of solid material comprising an active ingredient) comprises a plurality of tubules having a length of 0.5 micron to 3 mm., a substantially uniform internal cross sectional area corresponding to an inside diameter of 5 to 1000 microns and a substantially uniform wall thickness corresponding to an outside diameter of 25 to 1100 microns. The tubules are incorporated into pharmaceutical or disinfectant tablets in an amount of 0.1 to 90% by weight of the tablet. They are preferably of a water swellable material e.g. ethyl cellulose, carboxymethyl cellulose, cellulose acetate, hydroxypropylmethyl cellulose, cellulose or gelatin, and have a bulk density of 0.1 to 0.6 gms/cc. They may be produced by sub-dividing hollow fibres, e.g. those commercially available for use in dialysis produced by extrusion, melt-spinning or coating a filamentous core and then dissolving the core. The tablets are prepared by mixing the material to be formed into tablets, if necessary after wet or dry granulation, with the tubules and then compressing the mixture into tablets using a pressure which does not permanently collapse the tubules. The tubules may be dyed prior to incorporation in the tablet to give a tablet having a coloured speckled appearance. If required, the tablets may be coated to control disingration time. In the Examples, pharmaceutical tablets containing aspirin, rifampicin, and quinidine sulphate are prepared. A disinfectant tablet for use in aqueous systems such as water closets, humidifier tanks and wading pools is prepared by granulating sodium bisulphite with ethyl cellulose and spray-coating the granulate with shellac, forming a second granulate of sodium iodide and ethyl cellulose, mixing both granulates with 2, 2-dibromo-3-nitrilopropionamide and tubules of hydroxypropyl ethyl cellulose and compressing into tablets. In use the nitrilopropionamide has an initial disinfecting action which is synergised by the sodium iodide; later slow release of sodium bisulphite then detoxifies the disinfectant.