A tablet can be imperfect in a number of ways and these defects and imperfections can either be found on the surface or in the interior layers of the product due to the formulation problems. In this tablet defect overview, we are focusing on the most common visible defects that can be discovered during the quality control, because an imperfect appearance of a single tablet in a package can raise serious doubts about integrity and quality of the product. Consequently, pharmaceutical companies continuously try to increase their efforts to assure high-quality of their products. Visual quality control can be done by various statistical schemes or by 100% visual inspection and sorting, either manual or automated. Due to the fact that statistical sampling schemes, that estimate the overall quality of a given batch of tablets at a certain confidence level, cannot assure the required quality of each tablet, they are being replaced by 100% visual inspection and sorting. Since manual visual inspection of large tablet batches is subjective, unreliable, slow, tedious and costly, automated visual tablet inspection systems are more and more commonly used.

1. Name - Tanaya Palit
Designation– Assistant Professor , M.Pharm
Tablets manufacturing defects and their remedies

2. Introduction:-
• An industrial pharmacist usually encounters number of problems during manufacturing.
• Majority of visual defects are due to inadequate fines or inadequate moisture in the granules ready for compression or
due to faulty machine setting.
• Functional defects are due to faulty formulation.
Manufacturing defects in Tablets:-
1) Picking and sticking
2) Capping and Splitting of tablets
3) Mottling
4) Weight variation
5) Hardness variation
6) Double impression
7) Binding in die
Tablets manufacturing defects and their remedies

3. Defects Reasons Correction
1. Picking and sticking
• Picking – Material adherence to
punch faces causes the removal of
material from tablet surfaces.
• Sticking – Adherence of tablet
material to the die walls. Causes
difficulty in ejection of tablet.
1. Improper designs of engraved
punches.
2. Poor maintenance of punches
surface.
3. Use of worn out punches and
dies.
4. Under died granules .
1. Proper designing of Punches.
2. Chrome plating of punch surface .
3. Proper quality of anti – adherents.
4.Adequate drying of granules.
2. Capping and Splitting of Tablets
• Capping – Partial of total
separation of top or bottom
portions of the tablet.
• Splitting of Tablets – Separation
of two or more layers.
1. Entrapment of air in granules.
2. Excess fines in granules .
3. Excessive drying of granules.
4. Use of defective punches and
dies.
1. Reduce the percentage of fines in
granules.
2. Maintenance of desired amount
of moisture.
3. Replacement of defective
punches and dies.
3. Mottling
• Uneven distribution of colour on
the surface of tablets.
1. Difference in the colours of
drugs and additives .
2. Migration of colour to the surface
of granules during drying.
3. Improper distribution of colours
in powder bulk.
4. Larger particles of dye.
1. Using a dye that can mask the
colours of all the ingredients.
2. Drying the granules at low
temperature .
3. Using the dyes of very fine
particle size.

4. Defects Reasons Correction
4. Weight variation
• Tablet will not have uniform
weight.
1. Poor flow of granules .
2. Non – Uniform particle size
distribution of granules .
3. presence of excessive fines .
1. Using proper concentration of
lubricants and glidants.
2. By uniform size distribution of
granules.
3. Decreasing the proportion of
fines.
5. Hardness variation
• Tablets do not have uniform
hardness.
1. If volume and material vary in die
cavity.
2. Distance between punches varies
hardness will vary.
1. Tablets should not be harder than
required.
2. Hard tablets may not disintegrate
in the required time period.
6. Double impression
• Double impression of monogram
on the lower surface of the tablet.
Occurs where the lower punch
have a monogram.
1. At the moment of compression ,
the tablet receives the imprint of
punches .
2. Free rotational travel of lower
punch after compression causes a
new lighter f the bottom of the
tablet.
1. By controlling the undesirable
movement of punches .
2. Using new punches with the anti
turning devices .
7. Binding in die
• Differences in punch lengths.
1. Lower punches of unequal lengths
changes die cavity fill volume.
1. Using good punches with
uniform dimension and die
control program.

5. Picking and sticking Capping Mottling
Weight variation Hardness variation Double impression Binding in die