L.B. Bohle - The coating experts

When it comes to the fast, problem-free and efficient coating of tablets, the Tablet Coaters from L.B. Bohle Maschinen und Verfahren GmbH (Ennigerloh) have been setting the standard for years.
Pharmaceutical film coating is a crucial process step in the production of solids. Tablets are often coated in order to modify the release of the active ingredient, to protect the active ingredient from light or moisture or to mask a bitter taste in the tablet formulation. Tablets are also masked with colour or coated with a film to make them easier to swallow.
The processing of Active Pharmaceutical Ingredients (API) in tablet coatings is becoming increasingly important. Both combination preparations and the combination of two non-compatible Active Pharmaceutical Ingredients (API) in one dosage form can be realised. It is also possible to combine different release profiles of the same Active Pharmaceutical Ingredient (API). The core contains the slow-release component and the tablet coating contains the fast-release initial dose. The formulation approaches sometimes consist of up to four different film application types. This leads to long process times. In order to successfully develop and produce such formulations, the uniformity of the tablet application, the coating uniformity, is a mandatory requirement.
The interaction of mixing, spraying and drying is elementary in Tablet Coating. All three processes must be carried out simultaneously with the correct settings in order to achieve optimum coating uniformity. The Tablet Coaters from L.B. Bohle are technology leaders in this area with the shortest process times, ensure the best production results and offer the best combination of the three process operations on the market:

Mixing

It is essential that the tablet cores move evenly underneath the spray cone without mechanically stressing and damaging the tablet cores. The perfect solution for this is an extended coating drum (length to diameter (L/D) > 1) with the welded-in mixing spirals patented by L.B. Bohle. The mixing spirals ensure continuous and gentle mixing of the flat tablet bed. This reduces the mass pressure within the tablet bed. The rotary movement of the coater drum generates radial mixing, which results in a tablet bed free of dead zones. The tablets do not experience any strong acceleration due to the continuous guidance with the help of the double spirals, so that no tablet breakage or even twin formation occurs.

Spraying

The drum geometry maximises the spraying area in the moving tablet bed. This enables the use of a large number of spray nozzles. Compared to conventional coaters on the market with L/D ratios < 1, L.B. Bohle coaters reduce the process time by approx. 30 % due to higher spray rates. In addition to the suspension, the nozzle type, the number of nozzles and their distance from the tablets are particularly important. L.B. Bohle offers various solutions for setting the nozzle-tablet bed distance, the spray angle of the nozzles and the pressure parameters for atomisation.

Drying

L.B. Bohle Tablet Coaters guarantee the best energy and material transfer thanks to a modified air flow. The process air is fed directly into the tablet bed. As a result, the air flows directly and calmly into the tablet bed and ensures rapid drying of the sprayed suspension. The spray nozzles are not exposed to the supply air flow for the entire duration of the process so that they remain cool during the spraying process. This minimises spray drying effects and achieves coating efficiencies of >95 %. This advantage is particularly important for active ingredient coating, as less spray loss and therefore more uniform tablet coatings are achieved.

Coating system for every requirement

The BFC Tablet Coater is the high-end version of all L.B. Bohle coaters and is characterised by high efficiency, optimum performance and the lowest spray losses. The BFC enables a reduction in process time of approx. 30 % with optimum coating uniformity. The integrated high-pressure washing system guarantees cleaning-in-place (CIP) with first-class results. The BFC coaters realise batch sizes of 50-980 litres. Due to geometric similarities, Scale-up is possible, as with all
L.B. Bohle coaters, is possible without any problems.
The BTC is the economical variant for all coating applications. With the BTC, L.B. Bohle offers a cost-saving system for more efficient and longer-running processes in pharmaceutical production.
The BFC Tripan is a particularly versatile system that can be operated with three drums. Batches of 7-75 litres can therefore be realised. The drums can be changed quickly and easily using a lifting device.
L.B. Bohle also has the optimum solution for research and development. The BFC 5 Laboratory Coater is designed as a stand-alone unit. The BFC 5 can be operated with two different drums, which enable a batch size range of 2-13 litres.
L.B. Bohle fulfils the increased demand for continuous processes with the ^KOCO® continuous coater. The ^KOCO® is based on the proven, patented design of all L.B. Bohle Tablet Coaters. The process is analysed using an integrated Raman probe.

Containment - no problem!

The number and scope of containment applications in pharmaceutical production has increased significantly in recent years. As a result, L.B. Bohle has frequently been able to realise containment solutions in the coating sector in all toxicity classes. The containment coaters are characterised by features such as automatic nozzle adjustment, infrared product temperature measurement, connection for cleaning and drying as well as the control integration of the containment flaps or side doors with inflatable seals.

Slotted coater drum for mini tablets

Mini tablets offer the advantage that several tablets can be administered together to apply the required single dose if necessary. In a specially slotted coater drum, which is provided with a corresponding perforation, not only normal-sized cores but also small cores with a diameter of 1.5 millimetres can be coated.

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