How To Improve The Success Rate Of Coating Is Particularly Critical For Film Coating Machine

During the process of tablet production, the purpose of coating is to improve the appearance of of the tablet, prevent moisture, protect from light, mask bitterness or unpleasant odor, and control the release site and release rate of the drug.

In the past, most of the traditional oral coating tablets were sugar-coated tablets, which were time-consuming, labor-intensive, and could not guarantee the quality.

In recent years, with the rapid development of pharmaceutical industry , film coating machine has gradually become a trend, and its efficiency is much faster.

It is reported that the film coating process is a relatively stable polymer coating that evenly sprayed on the surface of the tablet core by spraying to form a plastic film layer with a thickness of several microns, so that it can achieve a certain expected effect.

It is suitable for medicine and pharmaceuticals, food, health products and other industries on the surface of Chinese and Western medicine tablet cores, such as sugar coating, film coating and polishing and rolling into round pills.

Facing with the expansion of market requirements, there are many film tablet coating machine manufacturers in the Chinese market.These manufacturers can meet the needs of various types of film coating, and the gap between the R&D and production technology level of the industry and that of foreign countries is gradually narrowing.

Some domestic products have completely replaced imported products, and domestic film coating machines have achieved a lot of supply and export.

With the extensive appliance of film coating machine, how to improve the success rate of  coating machine becomes very significant. Some experts pointed out that coating success rate of film coating machine has a crucial relationship with its spray gun system.

Choosing a good spray gun system and optimizing the working conditions of the spray gun before coating is an important guarantee for successful coating production. So, how should the spray gun be optimized?

Some technicians who are specialized in the research and use of high-efficiency coating machine spray guns and have accumulated rich experience have given several opinions, which are only for industry reference.

First, you should check the the connection pipe of the spray guns whether it is leaking, whether the movement of the needle is flexible, whether the needle is in the center of the nozzle before coating. The industry professional indicates that these conditions will affect the efficiency and quality of coating.

Specifically, you should mainly check the position of the needles in nozzle. If the needle deviate form the central position, the proportion of the liquid of coating and the high pressure atomizing gas will change at the the nozzle.

Occasionally, spray pulses may also appear. In addition, the deviation of the needle from the center of the nozzle will also cause the gun to be closed loosely, and the coating drops will cause the accident of sticking.

Second, Checking the nozzle position. Under normal circumstances, the spraying position of the spray gun should be located at the upper 1/3 of the tablet bed when the tablet cores are flowing, and the direction of the spray should be as parallel as possible to the wind direction of the incoming air and perpendicular to the flowing tablet bed.

The distance between the spray gun and the tablet bed should be determined according to the requirements of different coating systems. For example, the distance for organic solvent coating is shorter, about 20-25 cm; the distance for aqueous coating is longer, about 25-30 cm.

Third, the coating effect depends on the degree to which the coating liquid is atomized. It is understood that the smaller the particle size of the droplets, the better the spread of the droplets, which is beneficial to reduce the roughness of the surface of the coating film, increase the gloss, and greatly reduce the probability of bridging.

At the same time, the droplets have strong stretchability, which also increases the drying speed of the droplets on the surface of the tablet core, thereby reducing the adhesion of the coating film. When the droplet particle size is too large or too small, the coating effect will be affected.

It is suggested in the industry that how to control the particle size of the droplet should be determined according to the specific coating equipment, the quality of the tablet core and the viscosity of the coating liquid.

In addition, when the spray fanning is wider, the uniformity of coating and color can be increased, and the amount of coating material can be relatively reduced.

It is worth noting that when users adjust the width of the spray fan as much as possible, they also need to consider the overlap of sprays between spray guns, in order to improve the coating efficiency, improve the uniformity of the coating, and reduce sticking.

China's film coating technology started late. In the late 1970s, various coating liquids and film coating processes developed by a few pharmaceutical research units and pharmaceutical factories appeared one after another, and were gradually popularized and applied.

In the mid-1990s, film coating technology was recognized and widely used in China, but many pharmaceutical companies have many problems in application due to technical reasons.

With the maturity of film coating technology and process in China in recent years, some domestic pharmaceutical companies have broken through technical difficulties, and the use of film coating machine equipment has become more and more extensive.

On the whole, there are various types of domestic coating equipment, and with the development and rapid progress of technology, more and more products with different functions are emerging one after another.

In this context, the industry professional predicts that China's coating machine equipment will usher in more opportunities with the development of the pharmaceutical industry in the future, and the market will continue to expand.

However, it should be noted that under the background of the continuous increase in the concentration of the current coating machine equipment industry, coating machine manufacturers need to accelerate the upgrading of innovative equipment, and pay more attention to structure, material, flexibility and product quality.