Tablet press Presster

In order to determine how useful the Presster would be in predicting the behavior of a formulation on a production tablet press, it was decided to do a retrospective evaluation of two products that are routinely manufactured in production. The conditions used for manufacturing the two products in production were simulated on the Presster and the results are presented in Figures 3 and 4. 

In an effort to overcome the dwell time/scale-up issues. Metropolitan Computer Corporation (MCC) has developed a single-station development tablet press that reproduces the compaction event time of manufacturing-scale tablet presses. The Presster (see Fig. 6) can be set up to match the rate, roll wheel configuration, and tooling of any manufacturing-scale tablet press. This enables the formu-lator to eliminate compaction rate as a variable upon scale-up. It does require that early in development the formulation scientist identify the tablet press that the commercialized product will run on. This is in keeping with the theme of this chapter—begin a development project with the end in mind. 

The Presster is a single-station press that can mimic the load profile of any production press. The IVesster uses mechanical means to achieve geometric similarity with different tablet presses. Kinematic and dynamic similarities are achieved by matching the speed and force of compression. The process parameters for both press simulations are indicated in Table 4. 

Guntermann, A. (2005), The Presster—A tablet press simulator, paper presented at TabletTech, Brussels. 

Compaction simulators are single-station machines capable of mimicking the in-die compaction event that occurs on a rotary tablet press in real time. Simulators have been used to predict material behavior on scale-up and to evaluate various compaction parameters (punch force, ejection force, displacement, speed, etc.). Hydraulic compaction simulators (ESH) as well as mechanically driven machines (i.e., Presster and Stylecam ) are available for such studies. 

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. 

Thus, using mechanical similarity, all of the scale-up fact are matched, namely, the compression force, the speed, and the shape of the force profile. To use Presster, first a production press to be simulate should be selected, and the compression wheels with a matching diameter should be installed. Then, production speed should be selected in terms of tablets per hour. 

RPM, or dwell time. The Presster will mimic the selected production press speed and compression force profile and will allow us to make one tablet at a time. 

As a high-speed single station press, mechanical compaction simulator will be able to plot compressibility profiles, Heckel graphs, calculate work of compaction, and virtually any other imaginable variable that is of interest to formulators. Tensile strength of tablets made on a Betapress and The Presster was similar. ... 

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