摘要 |
A method that intermittently or continuously introduces a known mass of fine powder into an aerosolization chamber. The dry powder is aerosolized and, in one preferred method, the aerosol powder charged. Charged powder is then electrostatically deposited into or onto unit dose package substrates as these packages are sequentially moved through the deposition region. The packages are arranged in a continuous line either around the circumference of a circular package transport or in a continuous line on the surface of an endless belt. As each package traverses the precipitation region, a small amount of powder is deposited. The number of packages, the package velocity and the aerosol deposition rate are selected so that a large number of passes are required to fill each package to the required dose level. It is this continuous sampling, or time division sampling (TDS), that very uniformly divides the pre-determined quantity of powder uniformly among the many packages. |