Wet granulation processes

Granulation is a size enlargement process, where individual powder particles, usually of several different components, are aggregated together to form a larger structured particle where the original particles can still be distinguished. Granulation of one or more drugs and excipients is a common first step in the manufacture of tablets or capsules for pharmaceutical drug delivery. Although direct compression is possible, granulation usually ensures good flow properties and uniform bulk density essential for tabletting, and reduces the risk of segregation by creating multicomponent granules with more uniform composition than the dry blend. Dry granulation, also known as roller compaction, uses compressive forces to form the aggregates, and is covered in detail in Chapter 38.