How To Solve The Phenomenon Of Sticking And Splitting In The Process Of Tablet Pressing?

Tablet pressing is a common process in pharmaceutical production. But you will come across the sticking and picking problem in the tablet pressing process. The powder particles adhere to the surface of the punch and cannot form a smooth surface sheet, which makes the tablet product unqualified.

In view of this situation, in order to ensure that the product is not wasted, you have to visually monitor and manually pick the tablet during the tablet process, but this will greatly reduce the production efficiency and product yield. So, how to solve this phenomenon?

At present, the industry says that sticking and picking may occur at any stage of the tablet pressing process, but it has a characteristic of foreseeability, to determine properties such as the moisture content of particles can help you predict whether a product is sticky or not. Causes of sticking may be related to the product, equipment, upstream process or tablet press operation.

It may also be a combination of several factors. In this regard, the person listed some reasons and solutions for sticky red made a brief summary.

The problem of products

When products are pressed for the first time, you need to adjust the weight of the tablet first, and then adjust the thickness of the tablet. The hardness of the tablet is determined by factors such as tablet weight, tablet thickness, tabletting speed and holding time.

If there are some pressure-sensitive particle occurring sticking and picking problem, you can quickly press a few laps of very hard tablets, using the pressure to bond the particles into a tablet, and take away the powder that sticks to the punch. But you need to focus on the magnitude of the pressure. If the press exceeds the trimming die may cause in die damage or even breakage.

Moreover, experienced operators can judge the machine whether there is sticking and picking through the sound of the tablet pressing machine.

If there exists sticking and picking phenomenon, you can change the setting of the pressure. If pressure increases, you should reduce the tablet thickness, decrease the precompression thickness, or decrease the tabletting speed.

Equipment problem

You’d better choose the regular die equipment manufacturers. Because manufacturers generally do some work to avoid sticking and picking problems. You can also customize punches with sticking characteristics, and also change the height of the lettering and the size of the corners to reduce the risk of sticking.

In addition, the brightness of the steel materials’ surface can also cause sticking and picking.

For example, Type D2 and Type 440C steels contain more chromium than other types of steel, which reduces stick punch.

At the same time, a special chrome coating can be used to form a die with high hardness and wear resistance. However, industry insiders also reminded that if the product itself is relatively wear-resistant, the chrome-plated coating may soon be polished.

The problem of air trapping

It is understood that air may be sucked into the concave surface of the punch in the process of tablet pressing, so that the air forms a soft area on the surface of the tablet, causing sticking and picking. Also, this happens when the sheet is relatively soft.

In terms of this situation, the solution that is provided for you is to make sure this machine has a proper pressure-keeping time, discharging the trapped air, the main pressure can also be increased as much as possible. If the above adjustments can not be achieved, you can take tapered dies to help to expel air into consideration.

It is worth mentioning that due to the relatively small gap of the new die, it is easier to trap air than the old die, and a series of situations such as hardness, sticking, and capping may occur.

Not lubricated properly

The function of lubricate is to prevent the powder from adhering to the die, middle die and other metal substances during the tabletting process and it can also promote the automatic film part.

However, you need to pay attention to using the proper way when you use the lubricate. If not, you will not play the role of lubricant properly.

Generally speaking, if you need to preprocess to remove the mass and bigger particles, you need to mix the lubricant well and don't over-lubricate or sticking and picking will also occur.

Upstream process problem

For example, improper use of adhesives, incomplete drying of products, etc., can also cause sticking. In this regard, different problems should be solved accordingly.

Different types of tablet presses have different functions and applications, but they will usually encounter the same problem called the problem of splitting. So why does splintering happen? The main reason for this is that there are too many fine powders in the particles, and there is air in the particles during compression.

The speed of compression is relatively fast, and the gap between the punch and the die hole is relatively small, and the air is not excluded from the particles during compression, it is enclosed in the sheet, and when there is no pressure, the air expands and this causes splintering.

Here are some ways to solve splits in different situations to share with you.

Excessive pressure cause splitting

When the particles are under pressure, the extent of swelling will also increase, the binding agent’s combing ability can’t stop its swelling, so the splitting occurs.The best way is to reduced pressure.

Unsatisfactory splits on punch and die hole

If the die that has been used for a long time is gradually worn out, which mat cause upper punch to be inconsistent with the die hole, and the upper punch has a sharp inward curling edge. If it is out of shape and deformed, the appropriate mold should be replaced in time.

Split due to unsatisfactory particles

When the texture is loose and the fine powder is too much to cause cracks, the improvement method should adjust the concentration and dosage of the binder, and improve the granulation method to overcome. When the granules are too dry and the drug containing crystal water loses too much to cause splits, the water content of the granules should be controlled according to different varieties during granulation.

Splinters due to improper selection of binder

During granulation, if the binder is too small, and the viscosity is insufficient, the particles will be dried. If there are too many fine powders, the dry particles will be too hard, which may cause difficulty in disintegration and one-sided pitting.

Therefore, the binder should be added appropriately; if there are too many fine powders, a little can be sieved out; the particles are too hard, re-granulation should be reworked and a disintegrant should be added.

In fact, in recent years, with the rapid development of the pharmaceutical market, tablet press manufacturers have ushered in good opportunities and challenges. The tablet press industry and enterprises also need to continuously strengthen the pace of transformation and innovation.

According to reports, the whole machine adopts double-sided tabletting and double-pressing type, which has the advantages of large number of punching dies and high output, which is suitable for large-scale production.

In conclusion, the occurrence of sticking and picking and splitting during tabletting may be related to one or more factors. So you need to check the cause from the upstream and make a timely solution under the condition of ensuring that the device is in good condition.