1. Picking:
o
Picking happens when a part of the
tablets gets sticks to the punch surface and gets eroded from the tablet
surface
o
This mostly happens with the upper
punch. And if this is left unchecked then this may lead to weight
variation
too.
Sno Cause Remedy
1. Due The
to engraving or embossing on letters to be embossed should be in large
the upper punch size particularly on small punches,
or the size of the tablet be increased.
2. Rough The
punch surface punch surface should be coated with
chromium so as to get a smooth non
adherent face of punch.
3. Sticky Colloidal
surface of tablet silica may be added in the formula as
polishing agent to avoid sticking to
the punch
4. Too Reduce
deep dividing lines the depth of the division.
5. Excess Proper
moisture. drying of granules.
6. Hot The
granules while compression granules are to be dried so that they do not
stick.
7. Excess Reduce
2. binder. the amount or change the binder so that the
adhesive force is reduced and
more cohesive it becomes.
Sticking:
o
It refers to the sticking of the tablet
material with the die walls.
o
Due to this sticking with the die walls,
additional force is required to eject the tablet form the die walls.
o
Sticking also causes production of
tablets with rough edges.
o
If this problem persists, then this can
cause chipping of the tablet.
o
It produced unusual stress on the cam
track and punch heads resulting in their damage!
Sno Cause Remedy
1. Low Increase
pressure the pressure of punching
2. Fast compression Increase
the contact time by reducing the speed
3. Greater Reducethe
3. concavity of the punch concavity of the punch to optimum level.
Binding:
o
Binding is sticking of the tablet to the
die and does not eject properly out of the die.
o
It may be mainly due to lack of proper
lubricant or less quantity of lubricant, or may be due to excess
moisture in
the tablet.
Sno Cause Remedy
1. Less Increase
or incorrect lubricant the conc of lubricant or use appropriate
lubricant
2. High The
moisture content of the tablet granules are to be properly dried.
material
3. Hard Reduce
granules reducing the the size of the granules by passing through
effectiveness of lubricant 30 mesh so that increased surface
area can increase the chances of even
binding of the lubricant.
4. Worn Polish
out dies walls the dies properly
5. Excess Reduce
4. pressure in the die the pressure with in the die.
Chipping:
o
Chipping usually happens around the
tablet surface, small pieces are broken out or chipped out of the tablet.
o
It is mainly due to improper machine setting, like
ejection of the tablet.
Sno Cause Remedy
1. Too Moistane
much drying the granule with an hygroscopic substance
2. Worn Polish
out punches the punch surface to get a smooth finish
3. Sticking Addition
of the tablet material to the of proper lubricant and properly dry the
punch granules.
4. Non Polish
cylindrical dies with gap in the the dies so that they become cylindrical
edges shape.
5. Mottling:
o
Mottling is uneven distribution of the
colour on the surface of the tablet, with dark and light patches on it.
o
It is mainly due to different
colouration of the excipient or the degradation product of the tablet is
coloured.
(7)
Sno Cause Remedy
1. A The
dye may cause mottling when it formulator is intended to change the
migrates to the surface during solvent system, binder system, drying
the granulation temperature.
process
2. When The
coloured binder solution is not addition should in the sequence of First the
evenly distributed during mixing powder colorant is added
process followed by the binder like acacia or
tragacanth, followed by the addition of
granulating liquid, and properly mixed.
3. A Addition
colored active ingredient used of appropriate colouring agent.
along with colourless excipients.
6. Capping:
o
Capping is a complete or partial
separation of the upper or lower surface of the tablet horizontally,
when the
tablet comes out of the die.
o
When the air is entrapped in between the
tablet material in a die, and when the material gets compressed
between the two
punches, the air entrapped also gets compressed, but when the
pressure is released
on the tablet I.e. when the two punched move apart and the tablet
ejects out of
the die, the compressed sir expands and leads to capping.
Sno Cause Remedy
1. Large To
number of fines in the material remove the excess of fines the granulation
material should bee passed through
100 to 200 mesh.
2. Improperly Dry
dried granules the granules properly.
3. Inadequate Increase
or improper binder the quantity of binder or use and
appropriate one.
7. 4. Compression Compress
may not be firm due to cool the tablet material at higher temperature.
temperature
5. Improper Correct
setting of the lower punch, height of the lower punch should be
which adjusted so that the tablet is smoothly
causes the sweep off blade to cutejected out.
the surface
Lamination:
o
It is similar to capping but here the
tablet gets separated into layers.
o
It can once again occur due to the air
entrapment or due to the high speed of turret
Sno Cause Remedy
1. Fast Precompression
decompression of the tablet step should be included in the process, so
that the pressure at the final compression
is reduces.
2. Granules Suitable
may contain oily or waxy adsorbent or absorbent should be added.
material
8. (8)
(tablet capping and lamination)
Double impression:
o
It is seen when the tablet punches have
engraving or monograms on it to be embossed on the tablet.
9. o
When the tablet material comes into the
die for the compression both the punches come in contact with the
tablet
material and compress it, the next step is ejection of the tablet from
the die,
o
During ejection process the lower punch
travels a small distance down and then comes up to give a gentle push
to the
tablet, at this point when the lower punch moves down and comes up
it moves in
a swirlling motion, due to the free rotation when it comes in contact
with the
tablet for the second time to push it up it leaves another impression on
the
tablet. Which is leads to double impression.
o
To avoid this key are to be used along
the sides of the punches, so that it prevents rotation of the punches.