A coating machine is a device used to coat the surface of tablets, pills, granules, and other pharmaceuticals with a thin film or sugar coating. It can be mainly classified into the following categories:
Classification by Coating Method:
Rotary Coating Machine: This is the most common coating equipment. Its working principle utilizes the rotation of the coating pan, causing the material to tumble continuously within the pan. Simultaneously, a coating liquid is evenly sprayed onto the material surface through a spray gun. Under the action of hot air, the solvent in the coating liquid evaporates rapidly, and the coating material forms a uniform thin film on the material surface.
Fluidized Bed Coating Machine: Also called a boiling coating machine. It uses airflow to fluidize the material in a fluidized bed. The coating liquid is sprayed into the fluidized bed through a spray gun, fully contacting the material and drying to form a film. This coating method results in uniform coating, fast coating speed, and allows for continuous operation.
Pressure Coating Machine: The tablet core is placed in a coating mold, and the coating material is coated onto the surface of the tablet core through pressure. This method is suitable for applications requiring high coating thickness and uniformity, and can produce double- or multi-layer coated sheets.
Classification by Automation Level:
Manual Coating Machine: Requires manual operation for each step of the coating process, such as material addition, coating solution spraying, and temperature and rotation speed control. Suitable for small-batch production or laboratory research.
Semi-Automatic Coating Machine: Some operations are automated, such as coating solution spraying and temperature control, but manual loading and unloading of materials and adjustment of some parameters are still required. Higher production efficiency than manual coating machines, suitable for small to medium-scale production.
Fully Automatic Coating Machine: Equipped with a highly automated control system, it can automatically convey materials, precisely spray coating solution, automatically regulate temperature and humidity, and monitor and record the production process. Suitable for large-scale industrial production, ensuring the stability and consistency of coating quality.
Summary
Different types of coating machines may differ in structure and operation, but their basic working principle is to uniformly coat the surface of drug formulations with coating materials in order to improve the appearance of drugs, enhance stability, and control drug release.