What is film Coating?
· Definition
Film Coating is the process of applying a thin polymer-based coat to a solid pharmaceutical medicine in multiple forms such as tablets, capsules or pills, in the prescribed dosage. The thickness of the coat could be anywhere between 20-100 µm. There are many methodologies utilized to achieve the desired levels of coating considering the colour, gloss, shelf life, and branding. (1)
• Brand Names
Many brands make film-coated tablets and pills. Few of the most popular brands include Riluzole, Nexaware, Maviret, Fycompa, Acifix, Alton, Disprin, Eprazol, Angina, Caid, Esmax, Cospra, Esmotac, Detonix, Epa, Eso, Esotid, Esomiloc, Kentop, Keto-A, Nixpan, Maxima, Onepro, Opton, Pansec, Pantex, Pantosil, Prazolin, Pramax, Progut, Protopa, Rabeprol, Rabifast, Rabimed, Sergel, Versal, Trupan, Zerofen. (2)
Film coating in different product forms and specifications
• What is film-coating in pills?
The protective coating around the pills functions differently based upon the need. The purpose of coating could be to protect the chemical inside by encompassing it or mask the taste of the bitterness of the drug, or from avoiding the pill getting dissolved in the stomach due to its acidic nature. Examples of some ingredients used in pill coating are “shellac” (excretion from laccifer lacca or kerria lacca, a bug of the lac family) and “carnauba wax”, a product derived the carnauba palm leaves. (5)
• Film-Coated Tablets:
Coating in tablets can be film-coated or sugar-coated or enteric-coated or modified release. The film-coated tablets protect the tongue from the unpleasant flavour and also protect the drug from moisture and light. The film eventually breaks down with agitation and huge amounts of moisture and gets absorbed by the body. Hence, it doesn’t make a difference if it is crushed or consumed as it is. (3)
• Tablet Coating Process:
The process of film coating involves the deposition of a thin layer of film-forming polymeric onto a product substrate. This is subjected to efficient drying, a high degree of automation and coating time. A suitable polymer is dissolved in the suitable solvent along with other plasticizers and pigments. This particular solution is then sprayed on the rotating bed of the fluidized tablet. Further drying process makes sure to leave a thin layer of coating around the material. The raw materials used in coating are generally- polymer, plasticizer, colourants and solvent. Additionally, some flavours and sweeteners may also be added to enhance the taste of the tablet. (4)
What are the main film coating techniques?
• Paint Protection Film VS Ceramic Coating
Paint Protection Film (PPF) - PPF offers good protection against abrasions and reduces the glossiness. Self-healing, absorbing minor scratches, the disappearance of swirl marks, and the prevention of hard water spots are some of the properties of PPF.
Ceramic Coating- Ceramic coatings are much more of a permanent solution than the PPF. The glossiness is enhanced when a ceramic coating is applied. Easy cleaning, low maintenance and hydrophobic are some of the properties of ceramic coating. (12)
• Thin Film Coating - How Does Dip Coating Rate Effect Thin Film?
The process of dip coating is done by immersing in a solution of substrate of coating material and then withdrawing. The film thickness depends on the immersion time, withdrawal speed, dip-coating cycles, surface tension, density and viscosity, evaporation condition of the coating solution and the substrate surface. The withdrawal and drying stages are critical in determining the properties of the deposited film. There are 2 types of forces applied here- entraining forces and draining forces. The balance between these 2 forces determines the thickness of the film coating. Further, the drying process involves the drying front coating, the falling rate period and the constant rate period. These rate periods further affect the thickness of the film coating. (6)
• Liquid Film Coating
A wide variety of applications of biotechnology and organic electronics require a selective deposition of liquid films on substrates. The process involves high uniformity, liquid confinement, and large coating speeds. Dip coating is a classic example of a liquid film coating technique. (7)
• How does film coating influence tablet costing
The methodologies used in tablet coating can significantly influence the costing, as the cost would depend on the machinery that is employed during the manufacturing process, the chemicals used such as polymers, plasticizers and other additives and solvents, the infrastructural costs involved in maintaining the process temperature and moisture conditions and the advanced automated technologies involved during the production. All these stated prerequisites are important in determining the desired levels of film coating achieved in various tablets or pills, which in turn results in the cost involved in achieving them. (8)
Film coating manufacturers in china
• SHANGHAI CHENGDONG TECHNOLOGY CO., LTD
Shanghai Chengdong Technology Co., Ltd is located in the Jinshang Industrial Park, Shanghai. They mainly engage in manufacturing, research and sales of Chinese Medicine Extraction Production Line. Their products include Supercritical CO2 Fluid Extraction device, different kinds of Evaporators (Fall Film Evaporator, MVR Evaporators), Multi-Function Extraction Pot, Alcohol Recovery Device, High-Efficiency Intelligent Coating Device, Vacuum Belt Dryer, Universal Mixer, Pyramid Mixer, etc. They have been in the industry for more than 30 years and export to countries like Mexico, the United States, Bulgaria, Myanmar, Vietnam, Bangladesh, etc. (13)
• KENO PHARMA LIMITED
Keno Pharma was founded in 2009, with its head office in Beijing. They are an international player in manufacturing and supplying pharmaceutical products. Their primary services include production and supply of substances, production and supply of packaging and consumable items, supply of high tech equipment for pharmaceutical and chemical industries, and construction of pharmaceutical plants or factories. (14)
• HUALIAN PHARMACEUTICAL MACHINERY CO., LIMITED
Hualian Pharmaceutical Machinery is into research, production and servicing of automatic packing machines of pharmaceutical, medical and food industries. Their popular products include tube filling and sealing machines, pill blister pack machine, automatic cartoning machines, high-efficient film coating machines, pre-made bag packing machines, automatic intelligent integrated machine production lines, capsule filling machines, etc. (15)
• Zhejiang Jiangnan Pharmaceutical Machinery Co., Ltd.
Zhejiang Jiangnan Pharmaceutical Machinery co. Ltd was registered in the year 1997, in the Zhejiang province of China. They have about 150-200 employees working in the manufacturing industry with product lines that involve pharmaceutical machinery, packing machinery and packing materials. Their main products include blister packing machine, tablet coating machine, carton machine, Soft gel encapsulation machine, paintball production line, capsule filling machine, tube filling and sealing machine, fluid bed dryer and granulator, etc. (16)
• Jornen Machinery Co., Ltd
Jornen Machinery Co., Ltd was founded in the year 1989 in China. They are pharmaceutical machinery manufacturers integrating development, production, service and marketing. Jornen covers products like blister line, film coating machine, tablet press machine, capsule filling machine, cartoner, etc. (17)
• Shanghai Pharmaceutical Machinery Co., Ltd.
Shanghai Pharmaceutical Machinery Co., Ltd (SPM) specialises in the manufacturing and designing of pharmaceutical machinery, and was founded in the year 1996. They have been serving global clients in 5 continents, over 120 countries. Their products range from solid Pharma (tablets, capsules, machinery, etc.) to liquid Pharma (injections, vial production line, eye drops, etc.) to semi-solid Pharma (vacuum emulsifying mixer, soft tube filling machine, etc.) to Pharma water treatment (pure water RO system, distilled water machine) to Pharma packing solution and laboratory instruments. (18)
• Aligned Technology Co., Ltd.
Aligned Technology Co., Ltd. was founded in 2004, in Shanghai. They are a technology-based company specialising in R&D, manufacturing, marketing and servicing Pharma machinery and packing machinery. They also deal with solid preparation equipment, oral dispersible film solutions, and oral dose process solutions. Their product range includes tablets, capsules, and ointments apart from machinery and packing solutions. (19)
FAQ:
What is the size of the thinnest film of a coating with n 1.42 on glass?
This include air on one side, the thin coat in the middle and the grass on the other side. The reflective index goes from left to right from 1 to 1.42 to 1.52. In this set up there is no consideration of face shift. The given wavelength of 6:50 notifies the destructive interference at the soonest possible film. The wavelength is 62nm. The end of the middle layer of the thin film has a thickness of 114.4 nanometres. (9)
How to remove the stuck-on film coating of a tablet without hurting the screen?
Sticking is a problem which is caused due to excess wetting and it occurs when the fluid delivery rate exceeds the drying capacity of the process. This can be reduced by reducing the liquid application rate or by increasing the drying air temperature and air volume. Other possible reasons could be inadequate atomization, poor product movement or poor distribution of spray. These issues can be resolved by increasing the pan speed, optimizing the uniformity of the solution delivery through the spray gun, and increasing the nozzle air pressure. The shape of the tablet can also be altered to remove the sticking issue, by increasing the face curvature to minimize the point of contact. (10)
How to apply plastic film coating to glass bottles？
Film coating on glass bottles is done in 2 stages- Hot End Coating and then Cold End Coating. During the manufacturing of the glass, as soon as the still-hot glass is transported on the conveyer belt, to prevent stress cracks, abrasion and scratches, the glass container is passed through a coating hood in which an organic tin mist is sprayed. This gets evaporated on the glass surface at 450-600℃, leaving behind a homogenous layer of tin oxide. This is further followed by the cold end coating. Depending on the desired thickness required, the glass is then evenly cooled from an input temperature of approximately 500℃ for 20 to 60 minutes. In the second stage of cold end coating, a thin film of polyethylene wax is applied as a water-based emulsion. (11)
Sources:
1) https://en.wikipedia.org/wiki/Film_coating
2) https://medex.com.bd/dosage-forms/46/tablet-enteric-coated?page=9
3) https://swallowingdifficulties.com/patients/what-is-a-tablet/different-coatings/
4) https://www.pharmapproach.com/tablet-coating-process-film-coating-2/
5) https://www.teachengineering.org/content/cub_/activities/cub_biomed/cub_biomed_lesson05_activity1_background.pdf
6) https://www.intechopen.com/online-first/75014
7) https://pure.tue.nl/ws/files/3581785/734478.pdf
8) https://www.mdpi.com/1999-4923/12/9/853/htm
9) https://www.numerade.com/ask/question/what-is-the-thinnest-film-of-a-coating-with-n-142-on-glass-n-152-for-which-destructive-interference-of-the-red-component-650-nm-of-an-incident-white-light-beam-in-air-can-take-place-by-reflection-2/
10) https://www.pharmapproach.com/common-defects-in-film-coating-process-causes-and-possible-solutions/
11) https://bnt-chemicals.de/en/glass-container-coatings
12) https://www.carguys.in/paint-protection-film-vs-ceramic-coating-which-is-better/
13) http://www.chengdong.com/
14) https://kenopharma.com/en/about-company-2/
15) https://www.hlyj.net/
16) http://www.jiangnan.co/
17) https://www.jornen.com/
18) https://www.spm.so/
19) https://www.aligned-tec.com/
(All Rights Reserved)