Pharmaceutical Manufacturing Handbook: Production and

ing at punches and dies. Low product yield, low crushing force, and further tablet
yams and chipping are other problems which have to be solved [33, 201] .
High tablet weight variation can be reduced by using weight control systems.
Further demixing of the tableted material has to be avoided, since demixing results
in higher tablet weight variation and content uniformity can no longer be achieved.
As already discussed, paddle feeders can be used to achieve mixing homogeneity
for problematic products and further spectroscopic techniques can be used for
control.
The problem of capping and lamination can be solved by increasing RH or
adding wetting agents. Further either external lubrication may help. Picking and
sticking of the tablets at punches and dies can be avoided by using lubricants as
discussed above.
A low product yield is caused by loss of material during fast production processes.
On rotary tableting machines this problem is solved by slightly lowering the
lower punches before the compression event starts.
A low crushing force is often caused by the composition of the special formulation.
If the formulation itself is not the reason for a low crushing force, compression
force can easily be increased. Another possible explanation can be low humidity of
the tableted product.
Finally tablets yam and chipping can occur before the tablets leave the die table
of a rotary machine. Usually the lower punches or the tablet scraper of the tableting
machine are not properly adjusted. Another reason can be low crushing force.
In conclusion, for smooth and perfect machine runs, product properties and
machine conditions have to be tightly controlled.
6.4.13
FUTURE OF TABLET PRODUCTION SYSTEMS
In principle tablet production systems have remained the same throughout the last
century. However, major improvements in instrumentation, data acquisition, and
analysis techniques have been made. Nowadays more sophisticated data acquisition
and analysis techniques are available which facilitate and improve interpretation of
tableting data.
In order to facilitate scale - up, more sophisticated simulation systems can be
thought of. They will be a real help for scale - up with small amounts of material as
available in early development of formulations.
Further quality control of the tablets during tableting or shortly after has become
more important. Recent trends show improvements for production in a GMP environment
by isolating the production unit from the machinery. For the near future
the implementation of the PAT initiative of the FDA is conceivable.
REFERENCES
1.
2.
REFERENCES 1087
Brockedon , W. ( 1843 ), Shaping pills, lozenges, and black lead by pressure in dies, British
Patent 9977.
Leuenberger , H. ( 1997 ), Research in solid dosage forms — An obsolete topic? Pharm.
Dev. Technol. , 2 , vii – viii .