| abstract |
One or more of a range of thermoplastic materials, typically a soluble polyvinylalcohol, are used to make, by an injection-moulding technique, a capsule that will at least in part dissolve in the body. Most preferably the capsule has raised or incuse portions moulded into its external surface, which patterns may define a code or simply be rib-like, either to reduce its apparent surface area or to assist in its partial dissolution. The injection-mouldable material can contain one or more particulate hydrophobic solid in order to both reduce the surface tackiness and also increase the density of the capsule, or can contain one or more particulate solid in order to accelerate the rate of dissolution of the capsule, for example in the different conditions of pH which exist in the gastro-intestinal tract. It can also be made from materials that will not hold a static charge. |