Coating problem

Hi colleagues,

could you give me some advice how sort out the problem with coating. About 1.5 % coating tablets have the following defects: tiny uncouting (white) spots into logo and on the edges of tablets. We tryed working with different parameters and their combinations (high or low: pan speed, spay rate, atomising and spray pressure). It didn’t make sense. Сomposition of coating suspensiion: hyprolose, titanium oxide, ferric oxide and macrogol.

check out the concentration of titinium and macrogol.higher conc of these may case the said defect.

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  1. You should be Properly Colloid the Coating Solution and passed from Muslin cloth (#200 to #300).
  2. Replace your coating solution to Ready made film coating materials (like Colorcoat, Opadry, Aquadry and Bharat Coat).

KAPL, Dharwad (Karnataka)

Dear colleague,

thanks a lot for your answers, but it’s impossible to change the concentation of ТiO2 and macrogol and replace our coating solution to Ready made film coating materials

what is the previous batch history?u faced this problem just in this batch or faced same problem in all previous batches?

in all previous batches.

Then surely its coating formulation problem.

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while coating operation coating suspension is subjected to continous stirring or not?

You should pass all materials through 100mesh and use 0.2% tween 80 as wetting agent for better dispersibility. This will solve the problem.

continue stirring but very slowly

I cannot use tween because it’s not in formula.

Try to pass all materials through 100mesh

Can you provide more details about coating equipment make and capacity.

  1. Run your product in other available autocoater
  2. Procure same materials from different approved vendor/ Branded Coating excipients

can you share pics of defected tabs?

Have you checked the spray pattern? Made changes to pressure, ect…?

It seems to be peeling of coating film?

Coating solvent is water or organic?

Tablet bed temp?