Tablet press refers to the machine that places particles or powder materials in the die hole and presses them into tablets by a punch. However, in the production process of tablet pressing, occasionally users report that the result of tablet pressing is not smooth. The following are two common problems of tablet pressing, as well as the corresponding solutions.
Looseness of effervescent tablet press
If the fineness of the drug is not enough, and the content of fibrous or elastic drugs or oil components is more, the uneven mixing will lead to the phenomenon of loose tablets. It can be overcome by crushing the drug through 100 mesh screen, selecting adhesive with strong viscosity, properly increasing the pressure of tablet press, and fully mixing the oil absorbent.
If the amount of binder or wetting agent is insufficient or the selection is improper, the particle texture will be loose or the particle size distribution will be uneven, and the coarse and fine particles will be stratified. It can be overcome by selecting proper binder or increasing dosage, improving granulating process, mixing more soft materials and blending particles.
The water content of the particles is too small, and the excessively dried particles have greater elasticity. The drugs containing crystal water lose more crystal water during the drying process of the particles, which makes the particles brittle and easy to loosen. Therefore, the moisture content of particles should be controlled according to different varieties. If the particles are too dry, spray a proper amount of dilute ethanol (50% - 60%), mix well and press the tablets.
The phenomenon of looseness in the process of tablet pressing may also be related to the nature of the drug itself. For example, although the tablet with high density has a certain hardness, it can not withstand collision and shaking; the fluidity of particles is poor, and the particles filled into the mold hole are not uniform; or when there are larger blocks or particles or fragments blocking the particle scraper and blanking mouth, the filling amount will be affected.
In addition, the tablet pressing machine will also affect the effect of tablet pressing. If the pressure is too small, the punch length of the multi punch is uneven, the speed is too fast or the particles in the hopper are too much and too little. It can be overcome by adjusting the pressure, checking whether the die is complete, adjusting the speed and adding particles frequently to keep a certain amount of stock in the hopper.
Cracking phenomenon of tablet press of traditional Chinese Medicine
When the tablet is shaken or placed, it is called lumbar cleft if it splits from the waist; it is called top cleft if it splits from the top, and the lumbar cleft and top cleft are collectively called lobes.
The drug itself has strong elasticity, fibrous drugs or more oil-containing components. Sugar powder can be added to reduce the elasticity of fiber, strengthen the adhesion or increase the absorbent of oil medicine, fully mix and then press the tablet.
The adhesive or wetting agent is improper or the dosage is not enough, and the adhesion of particles is poor when pressing.
The solution is the same as that of loose tablet.
Some crystalline drugs are not fully comminuted. This kind of medicine can be fully crushed and granulated.
When the pressure is relieved, the air inside the tablet will expand and cause cracks, which can be eliminated by sieving off part of the fine powder and reducing the amount of lubricant.
It is reported that the pressure of the tablet press is too large, the rebound force is large and the tablet is cracked; the speed is too fast or the die does not meet the requirements, the punch is long and short, the hole of the middle die is worn, the middle part of the middle die is larger than the upper and lower parts or the punch is rolled inward, which can cause the tablet to crack when it is ejected. It can adjust the pressure and speed, improve the matching of die, check and change in time.
In addition, low room temperature and humidity in the tablet pressing chamber are easy to cause cracks, especially for drugs with poor viscosity. The air conditioning system can be adjusted.