Tablet press replicator

Considering the processing fundamentals of this dry process, almost all of the issues associated with the scale-up of more traditional film-coating processes are eliminated, and the key objective is to feed tablets directly from the tablet press into the electrostatic coating operation, and thence in to packaging. Thus, once the process is defined in terms of coating one tablet, it is replicated an appropriate number of times in order to coat all of the tablets in the batch. 

To test the foregoing dimensionless relationship, two powders (Avicel Pl 1101, a ductile, viscoelastic material, and Emcompress, a brittle material, blended with 0.5% magnesium steaiate) were compressed on the PressterTw, a single-station mechanical replicator of rotary tablet presses. In the first set of experiments, a 16-station Manesty Betapress (a research-scale press) was simulated at two speeds, 60 and 100 rpm. In the second set, a 36-station Fette P2090 (a medium-scale production press) was simulated at two speeds, 55.8 and 70 rpm. It should be noted that 100 rpm of the Beta-press corresponds to 55.8 rpm of the Fette 2090 in terms of the linear speed of the turret. Basic parameters for the two tablet presses arc presented in Table 3. 

More recently mechanical compaction simulators have been developed. The first was the linear mechanical rotary table ting machine simulator Presster (Figure 8), which was introduced in 1998 [55,56], It can mimic the mechanics of different rotary tableting machines and is called a linear rotary tableting machine replicator. The name Presster was combined from press and tester. 

Mechanically powered compaction simulators are also available to replicate the compression event of tablet presses (3). These machines leverage the design of traditional rotary tablet presses where the punches are forced between a set of roll wheels to enable the compression event. The punch type and roll wheels can be changed to replicate the compression event of different press types. In some models, the fill station, compression station(s), and ejection station arc aligned in series on a linear track, where the punches and die travel along this track from station to station to complete the fUl-comprcss-ejection cycle. 

Compaction simulators are most commonly used to replicate the compaction process of a rotary tablet press. Manufacturing parameters, such as production speed, dwell lime, compression force, precompression force are often studied using a relatively small quantity of bulk powder. These parameters can significantly affect tablet crushing strength, friability, and disintegration time. The relationship among compaction pressure. 

One enhancement of the tablet press is the capability to make multilayer tablets. This option was developed some decades ago for pharmaceutical tablets and it is now often seen in automatic dishwashing tablets. The multiple layers are achieved by simply replicating the fiU/compression stations on the press. Hence, the sequence for a two-layer tablet would be fill layer 1/compress/fill layer 2/compress/eject. To achieve a good bonding between the layers, the final compression is always at the highest force. 

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