The Sequence of Events in Tablet Formation and Importance of Press Instrumentation
1. History
• In 1952–1954 Higuchi and his group have
instrumented upper and lower compression,
ejection, on an eccentric tablet press
• In mid-1980s, custom-made press monitoring
systems were described .and the first Microsoft
Windows-based press instrumentation package in
1995.
• A new era of compaction research has begun with
the introduction of an instrumented compaction
simulator
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2. The sequence of events involved in
the formation of tablets.
Three steps:
1.filling
2.compression
3.ejection
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3. An instrumentation system on a tablet press is not a one size fits all. The
sensors as well as the software need to be tailored to the application
Example # 1
• Pre-Formulation: A Single station tablet press, specifically
• instrumented to produce large amounts of information with
as little as a couple of grams of material is best for early
characterization of the API.
• Sensors are used to measure both upper and lower punch
forces, punch movement, tablet ejection and radial die wall
forces.
• These sensors in conjunction with a software program
provide a tremendous amount of information with the making
of a single compact or tablet. 3
4. Example #2
• Production: Production presses need additional sensors in
addition to those used in the earlier development
machines.
• Sensors need to measure upper and lower punch
tightness. Displacement sensors are required to measure
weight cam and roll positions.
• The instrumentation system must be able to control the
press to optimize the production speeds while maintaining
the required weights. Tablets out of specification must be
rejected.
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6. importance of Press
Instrumentation
* Although they may appear simple, tablets are complex drug
delivery systems; Underestimating the importance of their
design, formulation and manufacture invites significant
production difficulties;
* thus Instrumented R&D tablet presses and data-collecting
software packages are critical for the success of a tablet
manufacturing process.
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8. Lubricant profile
• A certain quantity of lubricant must be present in the
granulation to reduce the friction at the die wall as the
tablet is being ejected, as well as to prevent sticking of
the tablet to the face of the punches
• Without instrumented ejection cam and take-off bar,
no objective estimate of an optimal lubricant level is
possible:
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9. Lubricant profile
This plot will help a formulator to determine the optimal amount
of lubricant
Obviously, one would try to minimize the ejection force (to reduce
wear and tear on the ejection cam), and yet to avoid the pitfalls of
having too much lubricant in the formulation!......why?? 9
11. they don’t require large amount of powder
and its structure is small.
they allow relatively inexpensive measurements of die
forces (no rotation of die table and therefore no need to
use expensive telemetry methods).
Also It can manufacture odd-shaped products with
a diameter of up to 20 mm. 11
12. drawbacks
1. special tooling is required (usually, F
tooling),
2. speed of compaction is too slow compared
to rotary presses
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the speed is a crucial factor in
tableting process
therefore the results obtained on
single punch presses do not
directly correlate with tablets
made on rotary machines
14. Multi stationpresses
Also known as Multi punches Tablet Compression
Machine/ Rotary presses
Advantages
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Cost-effective.
High safety
system.
High-speed
operation.
High overall
equipment
effectiveness.
Minimal
product loss.
16. Differences between single punch tablet
press and rotary tablet press
The vital
difference
Setting and
operation
Productivity Uses
single punch utilize only
upper punch
for
compression of
granules
Very simple less small-scale
production and
research and
development
of tablet
formulation
rotary tablet
press
utilize both
upper and
lower punches.
complex more esearch and
development,
scale-up, and
large-scale
production.
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17. High speed rotary tablet machine
• A high speed rotary tablet press can produce over
500,000 tablets per hour!
• Development in the design:
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Multilayer tablets
High speed needs high flow!
18. 18
https://www.youtube.com/watch?v=j6CC53hcY3A
Dosator filling machine :
A very free flowing powder isn’t required , as a
cohesive blug wouldn’t then form inside the
dosator tube
However, it cant be too cohesive since the powder
bed must be maintained at uniform depth.
The majority of formulations filled into hard
capsules are dry powders or granules
20.
Compressibility is evaluated by loading pressure onto a
powder bed while measuring the bulk density of the bed
Compactability is evaluated by measuring the tensile fracture
stress (TFS) of tablets as a function of compaction pressure ,If
the powder has poor Compactability, the resultant tablet
hardness will be low, and tablet defects,including breakage,
may result.
Manufacturability concerns tableting failure (e.g.sticking,
capping). If friction between powders and die wall is high, the
risk of tableting failures such as sticking and binding during
manufacture will be high
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Tableting properties:
