Tablet defects can come from any of the unit operations upstream and from the tablet press. The raw materials may be of poor quality or do not meet specifications, causing excessive fines that lead to a host of defects. The formulation may be the source of defects if the material does not compress well or the processing step specified within the formulation fail to produce a powder with a good flow, compressibility, and ejection properties. The processing and granulation of powder are often the sources of the defect. Every product behaves differently on a tablet press, even if it‘s the same product run on a different day. The variation often stems from changes in the properties of the raw materials—active ingredients and excipients- from batch to batch. Naturally, the goal is to minimize these changes. Tablet press operators, however, don‘t have any control over formulation and granulation. Tablet specifications are tight, and the list of possible defects is long: Variable weight, sticking, picking, capping, lamination, variable hardness, among others. This article focuses on these variations. It pinpoints the possible causes of these defects and offers advice on preventing and fixing the source of the problems.

1. TABLET DEFECTS AND ITS
RECTIFICATION
Prepared & Presented by :
Prof. Vedanshu R. Malviya
(M.pharm)

2. CONTENTS
Introduction
Defects in Tablets
Its Rectification
References

3. INTRODUCTION
 In the normal process of developing formulations,
and in the routine manufacture of tablets, various
defects are observed. Sometimes, the source of the
problem or the defect is the formulation, the
compression equipment, or a combination of the two.
Some defects are noticed immediately during
manufacturing but others may be noticed during
storage as in the case of capping.

4. DEFECTS IN TABLETS AND ITS
RECTIFICATION
 CAPPING AND LAMINATION
 PICKING AND STICKING
 MOTTLING
 DOUBLE IMPRESSIONS
 BINDING
 CHIPPING AND SPLITTING

5. CAPPING AND LAMINATION
 Capping is defined as the partial or complete separation of the
top or bottom crowns of a tablet from the main body of the
tablet.
 Lamination is the separation of a tablet into two or more
distinct layers.
 These processing problems are readily apparent immediately
after compression or may occur hours or even days later.
 Subjecting tablets to the friability test is the quickest way of
revealing such problems.

6. CAPPING AND LAMINATION

7.  Air entrapment
 Reduce press speed
 Precompress granulation
 Reduce quantity of fine particles in the granulation
 Excessive pressure
 Reduce tablet weight and/or increase its thickness within
allowable tolerances
 Adjust pressure
RECTIFICATION

8.  Too rapid expansion of tablet upon ejection
 Taper dies
 Poor granulation
 Increase quantity of binder; use strong binder
 Excessively dry granulation
 Increase lubricant
 Excessive lubrication of granulation
 Decrease lubricant; blend all ingredients before adding
lubricant

9. PICKING AND STICKING
 Picking refers to a tablet
material being removed from
the tablets surface by a punch.
 Sticking refers to a tablet
material adhereing to die wall.
 Tablet materials adhering to
punches can accumulate to the
point of obliterating the tip
design.

10. RECTIFICATION:
Excessive moisture
 Check moisture content of granulation; drying
 Check room humidity
 Presence of low-melting-point substances
 Dilution with higher-melting-point materials
 Insufficient compaction force
 Reduce tablet weight and/or increase its thickness within
allowable tolerances
 Inadequate lubrication of granulation
 Check and/or adjust level of lubricant used

11. MOTTLING
 Unequal distribution of color on a tablet, with light or dark
areas standing out in an otherwise uniform surface.

12. RECTIFICATION:
Drug whose color differs from the tablet excipients or
a drug whose degradation products are colored.
 Use of colorants
Migration of dyes to the surface of granulation during
drying
 Change the solvent system
 Reduce the drying temperature
 Grind to a small particle size

13. DOUBLE IMPRESSION
 This problem is encountered with punches that have a
monogram or other engraving on them.
RECTIFICATION :
Rotation of punches
 Adjust antiturning devices
 Use keyed punches

14. BINDING :
Sticking of the tablet to the die and does not eject
properly out of die.
 With excessive binding the tablet sides are cracked
and it may crumble apart.

15. RECTIFICATION:
 To moist granules and extrudes around lower punch.
•Dry grannules properly
 Insufficient or improper lubricant
• Increase the amount of lubricant or use more effective lubricant
Too coarse granules
•Reduce granular size,and more fines
Granular material too warm , sticks to the die
•Reduce temperature
•Increase clearance if is extruding.
.

16. CHIPPING OR SPLITTING
 Poor surface finish on punch tips;
worn punches and dies
 Poor tooling design
(e.g., sharp embossing or bisect lines)
 Polish punch tips; replace
punches and dies

17. RECTIFICATION:
 Sticking on punch faces
• Dry the granules properly
Or increase lubrication
 To dry granules .
• Moisten the grannules to plasticize
add hygroscopic substances.

18. REFERENCES
 Herbert A. Lieberman, Leon Lachman, Joseph B.
Schwartz, Pharmaceutical dosage forms : Tablets,
Second Edition,vol 3.
 James Swarbrick, James C. Boylan, Encyclopedia of
Pharmaceutical technology, Volume 15, 1996.
 James Swarbrick, Encyclopedia of Pharmaceutical
technology, Third Edition, Volume 6, 2007.
Website:
 www.pharmainfonet.com

19. THANK YOU