With the development of medical technology, the current drugs are not limited to capsules, tablets, granules, and liquid medicines. These have been difficult to meet the needs of external drugs in medicine. The emergence of drug films has expanded the library of external drugs . A new dosage form that combines ointment and tincture. It has a wide range of administration routes, such as oral administration and external application. External application includes multiple parts such as oral cavity, skin and mucous membranes, and can be used for local or systemic diseases. The drug content of the film is accurate and stable. Good, fast absorption, high curative effect, convenient application 2. In recent years, the research on medicinal film has been increasing year by year , including traditional Chinese medicine and western medicine film. At present, some products of medicinal film have been officially put into production, such as compound Qingdai loose film, clotrimazole Drug film, norfloxacin drug film, etc., have achieved good clinical results, as shown in Figure 1-1 are traditional Chinese medicine and western medicine film.
At present, the preparation method of medicine film mainly contains: film coating method, extrusion method, calendering method, solvent method etc., mainly acts on surgical disease, as dermatology film, otolaryngology film, burn department film ) etc. At present, the film coating method is more researched in the film preparation of traditional Chinese medicine. This method is also often used in domestic film preparation. At present, the preparation of drug films in hospital preparation rooms mostly adopts the method of manual film formation. This method has low efficiency, is greatly affected by human factors, and the thickness accuracy is difficult to control. Although some pharmaceutical factories have begun to use machinery to prepare drug films, it is difficult to control the accuracy and ensure the quality. Film coating machines usually use the method of coating and film formation. The film coating machine has the characteristics of fast film forming speed, high efficiency, small equipment size, low cost and high reliability. Compared with the methods of extrusion, calendering, and solvent method, the film coating machine can prepare different Chinese medicines, western medicines and other ingredients of the film, etc., and has the characteristics of a wide range of applications.
At present, the technological process of drug film coating is: preparing film-forming drug slurry → adding drugs and additives→degassing → injecting quantitative drug → coating film to catch film → drying and forming-→defilming → measurement. The film coating method is to pour the prepared film slurry into the container of the film machine, control the number of turns of the motor to control the amount of film slurry added, and squeeze the film slurry onto a flat plate ( Such as a flat glass plate) with a fixed- diameter roller on the top of the flat plate to spread the slurry to form a film 4, remove the solvent after natural drying or low-temperature heating, and remove the film to obtain a drug film, which has a simple structure and high forming efficiency51. The new drug film coating machine researched in this subject can realize the function of fully automatic drug film formation, and can reduce the workload of workers.
The gap flow field analysis of the slurry film formation is mainly to study the pressure change, volume fraction change and film thickness change of the slurry in the gap flow field under the pressure of the roller, and to study the change of the drug film thickness in the gap flow field. The regularity provides data support for the follow-up study of drug film formation.
The control system of the film coating method mainly includes: PLC controller, stepping motor, driver, photoelectric sensor, man-machine interface and other components to realize the control of speed and position ; the film coating process Parameter display and online parameter modification, convenient operation and reliable control.
The film coating machine is mainly used in the film formation of western medicine and traditional Chinese medicine, and also in the film formation of other viscous liquids. In addition to the matching scraper and wire rod to control the film thickness, it also reduces various errors, such as eliminating the coating in time. Speed, applied pressure, human factors and other errors. At the same time, according to the needs of material reaction, it also provides heating function and substrate adsorption function.
