| abstract |
In addition to the active ingredient, the capsules contain a nonionic surfactant consisting of a polyglycol ester or ether having hydrophilic and lipophilic portions, and an organic polymer which is capable of forming a free-flowing composition with the active ingredient and the surfactant. The essential point for the delay in release is the matching of the water-solubility of the active ingredient and the hydrophilic/lipophilic character (HLB value) of the surfactant as follows: -water-insoluble HLB value above 16; -sparingly soluble HLB value between 10 and 16; and -water-soluble HLB value below 10. - |