The objective of the present study is to verify that tablets, which are superior in physical properties, dissolution characteristics, and drug content uniformity, can be manufactured directly from granules prepared by an extrusion granulation process. First, granules were experimentally produced by extrusion, by changing the hole diameter and thickness of screen of granulator, the binder content, and the binder adding method. A fraction of the extruded granules were crushed and then sized. Tablets were manufactured from both extruded and crashed granules. As a result, it is possible to manufacture tablets which meet the targeted properties: tablet hardness ≥40N; disintegration time≥300s directly from the extruded granules without crushing and sizing. The tablets showed superior dissolution characteristic despite their high hardness. In addition, the drug content is uniform over the tablets even when the model drug content is extremely small (1wt%). The targeted physical properties can be obtained by adding 0.5wt% powder binder when the screen hole diameter (0.5mm) is smaller than the screen thickness (0.6mm), or by adding 1.5wt% powder binder when the screen hole diameter (0.5mm) is larger than the screen thickness (0.4mm).

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A tri-axial viewer was developed to measure the three-dimensional (3-D) shape of a particle from three orthogonal directions, t, u, and v, simultaneously. The angle of a particle's orientation δ was determined by the analysis of principal moment of inertia for the vertical image of particle under stable position. The angle, δ, was set at zero by rotating the stage of viewer (S/C method). The particle images through the tri-axial viewer were magnified ten times and the shapes were measured by an image analyzer. Shape measurements under random orientation were also carried out (S/R method). Canonical discriminant analysis proved that the differences in 3-D shape among particles were detected effectively by S/C method rather than S/R method. The largest correct discrimination ratio, D, was obtained in the combination of 3-D shape indices, ψ_1(tuv) and ψ_2(tuv). Therefore, both indices were found to be useful for evaluating particle's 3-D shape.

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