New tablet testing method predicted tableting failure at the commercial scale and will prove useful for scaling up production

Formulation design of granules prepared by wet granulation method using the Gamlen R series to avoid tableting failures


Takashi Osamura, Yoshiko Takeuchi, Risako Onodera, Masahiro Kitamura, Yoshiteru Takahashi, Kohei Tahara, Hirofumi Takeuchi


We previously determined “Tableting properties” by using a multi-functional single-punch tablet press (GTP-1). We plotted “Compactability” on the x-axis against “Manufacturability” on the y-axis to allow visual evaluation of “Tableting properties”. Here, we examined whether this evaluation method can be used in the formulation design of tablets prepared by wet granulation. We used the GTP-1 to measure “Tableting properties” with different amounts of binder, disintegrant, and lubricant, and compared the results with those of tableting on a commercial rotary tableting machine. Tableting failures (capping and binding in particular) occurred when samples that had been evaluated as having poor “Compactability” or “Manufacturability” on the GTP-1 were compressed on the rotary tableting machine. Thus, our evaluation method predicted tableting failure at the commercial scale. The method will prove useful for scaling up production.

This study was carried out using the Gamlen R series – formerly Gamlen Tablet Press (GT-1)


When tablet formulations are designed, it is necessary to understand “Tableting properties” and to determine the optimum type, grade, and amount of ingredients. “Tableting properties” consist of “Compressibility”, “Compactability”, and “Manufacturability”. “Compressibility” is evaluated by loading pressure onto a powder bed while measuring the bulk density of the bed. The properties of formulated powders have been investigated by using the equations of Kawakita and Ludde [1], Heckel [2, 3], and Klevan et al. [4]. Some constants in these equations are frequently used as indicators of “Compressibility”. “Compactability” is typically evaluated by measuring the tensile fracture stress (TFS) of tablets as a function of compaction pressure [5, 6]. If the powder has poor “Compactability”, for example, the resultant tablet hardness will be low, and tablet defects, including breakage, may result. “Manufacturability” concerns tableting failure (e.g., sticking, capping, and binding). If friction between powders and die wall is high (that is, “Manufacturability” is poor), for example, the risk of tableting failures such as sticking and binding during manufacture will be high. Sugimori et al. proposed that capping could be predicted from residual die wall pressure [7]. Urabe et al. suggested that estimation of general “Tableting properties” and failures was possible by using a micro-powder characterizer with infinitesimal quantities of powder sample [8, 9]. When the amount of lubricant in the tablet formulation is too little, “Manufacturability” becomes poor, leading to tableting failures such as sticking and binding [10, 11]. Too much lubricant in the formulation reduces “Compactability” and thus tablet strength [12]. The frequency of occurrence of tableting failures depends also on the punch used to produce the required tablet shape [13, 14].


Download full paper: New tablet testing method predicted tableting failure at the commercial scale and will prove useful for scaling up productions
(Scroll down document list to date of post: 21 August 2017)


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