Possible problems and solutions of tablet press in tablet preparation

1. Tablet debris The phenomenon of tablet splitting is called splitting. If the split occurs at the top (or bottom) of the tablet, it is generally called capping. This is a common way to spin off. Inhomogeneous pressure distribution and the resulting differences in elastic recovery are the main cause of gaps. The key to dealing with the debris problem is to use auxiliary materials with low elasticity and high ductility to reduce the overall elastic recovery rate of the material. In addition, too much fine powder in the granules, too dry granules, weak cohesion or insufficient dosage, too thick tablets and too fast inhibition can also cause splitting. 2. Loose tablet The phenomenon that the tablet is not hard enough and will crack when slightly touched is called tablet loosening. 3. During the operation of the tablet press, the surface of the sticky punched tablet is stuck to the chromatography or a small part by the puncher, causing the surface to be rough, uneven or depressed. Typically, this is sticky. If the edge of the tablet is rough or has voids, it can be called stick mold. The main reasons for sticking or sticking are: the particles are not dry enough or the material is not easy to absorb water, the lubricant is not selected correctly or the amount is insufficient, the surface of the punch is rusted or the lettering is rough and not smooth. The reason should be determined and dealt with according to the actual situation. 4. The difference in tablet weight exceeds the limit, indicating that the weight of the tablet exceeds the allowable range of the difference in tablet weight stipulated in the Pharmacopoeia. The reasons and solutions are: (1) The flowability of the granules is not good. Sometimes the number of granules flowing into the die hole is small, resulting in a large difference in the net weight of the tablet. It should be granulated again, or a better flow aid, such as fine powder silica gel, should be added. , to improve the fluidity of particles. (2) There are too many fine powders in the particles or the size of the particles is very different, resulting in heavy and light materials flowing into the die holes. The excess fine powder should be removed or re-granulated; (3) The particles in the silo are generally too small, which will cause fluctuations in the weight of the feed and make the difference in tablet weight beyond the limit. Therefore, the particles in the silo should always exceed 1/3. (4) The consistency of the punch and the die hole is not good. For example, there is a large amount of powder leakage between the periphery of the lower punch and the wall of the die hole, which will cause the 'squeezing punch' condition of the lower punch, which will inevitably cause insufficient material filling. Therefore, the punch should replace the head die ring. 5. Delayed disintegration (Shanghai Taborite tablet press) Factors affecting tablet disintegration include: (1) compressibility of raw materials; (2) strength of granules. When the strength of the granule (or material) is small, it is easy to crack due to shrinkage, so the porosity and diameter of the shrinkage tablet are small, and the disintegration of the tablet is slow. (3) Compression force. In general, the higher the pressure, the smaller the porosity and diameter of the tablet and the slower the disintegration of the tablet. (4) Surfactant. It cannot be assumed that adding a surfactant to any tablet will speed up its disintegration. (5) Lubricating fluid. Hydrophobic lubricating fluids commonly used in tablets can also seriously compromise tablet wettability. Therefore, in production practice, the type, dosage, mixing intensity and mixing time of lubricating liquid should be strictly controlled to prevent the tablet from disintegrating slowly. (6) The amount of binder. Molding of the tablet and disintegration of the tablet must be given due consideration, and proper binder and proper dosage must be chosen. (7) Type and amount of disintegrant. (8) Storage standards for tablets. After tablet storage, the disintegration time usually increases, which is mainly related to the temperature and humidity of the environment. 6. Exceeding the melting limit