Tablet shapes

Esophagus Ensure transit Adjust tablet shape Surface area/weight ratio... 

The extent of revalidation required for formulation changes should be determined on a case-by-case basis. Slight adjustments to the formulation may not require further validation work. This would include an adjustment of the excipient ratios, a change in tablet shape, etc. Specificity and accuracy should be re-evaluated for the inclusion of a new excipient into the formulation (e.g., antioxidants, dyes, preservatives). A change in the formulation such as going from a tablet to a capsule or from a liquid to a solid would mean a significant change to the formulation and complete validation should be performed. 

J.L.Ford, M.H.Rubinstein and F.McCaul, Importance of drug type, tablet shape and formulation on release from hydroxypropylmethylcellulose matrix tables, Proc. 6th Pharmaceutical Technology Conf. Canterbury, 7—9 April, 1987, Vol. 1, pp. 82-87. 

Tablet shape is fixed by the shape of the die cavity and the punch faces. 

The dies cracked due to the inordinate amount of force required to compact the tablet, coupled with a poorly designed tablet shape (kids/fun shapes). As the tablet press speed was increased, the dwell time of the compaction event decreased, thus increasing the amount of peak force required for compaction. 

Tablet properties Tablet properties such as hardness, shape, and intaglia-tion (if required) are important to obtain a good film-coated tablet. The tablet needs to be hard enough to withstand the coating process. If tablet attrition occurs, the tablets will have a rough surface appearance. For tablet shape, a round tablet will be easier to coat than tablets will multiple sides or edges because of the uniformity of the surface. For intagli-ated tablets, the intagliation style and depth should be developed to prevent fill-in or chipping of the intagliation.

J. L. Ford, M. H. Rubinstein, F. McCaul, et al. Importance of drug type, tablet shape and added diluents on drug release kinetics from hydroxypropymethylcellulose matrix tablets. Int. J. Pharm. 40 223-234, 1987. 

TABLE 6.21 Influence of Tooling Design on Tooling Strength with Tablet Shapes Depicted in Fig. 6.7... 

A majority of oral solid dosage forms are tablets and caplets. Tablets can be handled as slabs or cylinders. More accurately, the tablet shape has both slab and cylinder features. Drug release occurs through radial and lateral surfaces, and diffusion of a solute in a tablet is expressed by ... 

The implant consists of a tablet-shaped ganciclovir reservoir. The drag is initially completely coated with poly(vinyl alcohol) (PVA) and then coated with a discontinuous film of hydrophobic, dense poly (ethylene-co-vinyl acetate) (EVA). Both polymers are nonerodible and hydrophobic (the PVA used in the implant is cross-linked and/or high molecular weight, to ensure it does not dissolve when exposed to water). The entire assembly is coated again with PVA to which a suture tab made of PVA is attached (Figure 4.5). 

One of the best understood mineralization systems in terms of the microenvironment of nucleation is the mollusk shell, and in particular one of the seven structural types of mollusk shell, the nacre [99], The nacre has a simple geometry and is therefore a most convenient system to study in terms of nucleation. Observations of growing aragonitic tablet-shaped crystals show that the matrix surface at the location where the first crystals form is different from the remaining surfaces. This location can be differentially stained using dyes that have affinities for calcium and sulfate, for example [100], The surface topography is... 

The shape of the tablet alone can influence the choice of tableting machine used. Figure 18 shows some representative tablet shapes. The size, shape, and thickness... 

Solutions Decrease the excessive spraying. Check the tablet shape and bands. If the tablets are plane or almost plane, this continues until many of them stick together. 

Wilson, K., and Crossman, E. (1997), The influence of tablet shape and pan speed on intra-tablet film coating uniformity, Drug Dev. Ind. Pharm., 23,1239-1243. 

Relationship of punch key to tablet shape position will be influenced by tablet shape, take-off angle, and turret rotation Area between edge of punch cup and outside diameter of punch tip Relieved area between head barrel which provides clearance for die Contact area with press cams and initial contact with pressure rolls... 

D-4179 Single Pellet Crush Strength of Formed Catalyst Shapes Strength of spherical or tablet shaped particles individually crushed between two flat surfaces ... 

Fig. 13 Punch tip edges wear and deformation under load, effect on tablet shape and tip deflection.

Fig. 16 Examples of well-known tablet shapes. (Courtesy of Ritter Pharmatechnik, D-Hamburg.)...

Type RII contains tablet-shaped fragments with smooth larger ( upper and lower ) surfaces and rough to irregular smaller side walls . The larger surfaces have the morphology which is typical of undeformed bedding, and it is reasonable to interpret the... 

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