Problems during coating and trouble shooting

1. Created by Sucharita Mohapatra

2. Defects Generation During Coating Activity
Defects Nature Reason Picture
Picking And
Sticking
Coating removes a
piece of the tablet
from the core.
 Over wetting
 Under drying
 Poor Tablets Quality
Bridging Coating fills in the
letters or logo on the
tablet.
 Poor Design of the Tablets
Embossing
 High Coating Solution
Viscosity
 High percentage of solids in
the solution
 Improper atomization
pressure
 Excess application of the
solution.

3. Defects Nature Reason Picture
Twinning - Two tablets stick together
- Common issue in Capsule
shape tablets
 Low Pan RPM with
high spray rate
 Tooling Design
Peeling - Slight coating sheet
removed from the coated
tablets
 Coating solution not
sticking properly
 Over wetting
 High moisture
content in the core
tablets.
Defects Generation During Coating Activity

4. Defects Generation During Coating Activity
Defects Nature Reason Picture
Erosion Soft Tablet
Generation
 An Over Wetted Tablet
Surface
 Inadequate Drying
 Lack Of Tablet Surface
Strength
Mottled
Colour
Colour spots on
tablets
 Actual spray rate differs
from target rate.
 The tablets are cold
 Improper preparation of
solution
Shade
Variation
Uneven Spray rate  Gun Choking
 Solid Particles not dissolved
in water or solvent
 Improper preparation of
solution