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Name of Defect Illustration Definition Remedy
1. Chipping
Involves increase brittleness ofa tablet.
Caused by high degree ofattrition with the coating
process like: excessive use of
fillers and pigments, lowamount of polymers.
Increase hardness of
a film by increasingthe molecular weigh
of polymer.
2. Sticking
and
picking
Sticking involves sticking of
the tablets with each other andwith pan walls.
Picking is the aftermath case ofsticking involves adhering
of
some portion of coated layer to
pan or to another tablet at thepoint of contact.
Caused by higher rate ofcoating solution inefficient
drying.
Use optimum and
efficient drying
conditions.
Increase inlet airtemperature.
Decrease the rater oapplication of
coating solution by
increasing theviscosity of coating
solution.
3. Roughness
Involves presence dried sprayedcoating solution droplets
onto
the core.
Cause/s:Drying of solution beforereaching the surface of the
tablet during spraying.Excessive pigments
concentration.
Moving the nozzle
closer enough.
Reducing the degreeof atomization.
4.
Cracking
Happens when an internal stressexceeds the tensile strength
of
tablets.Cause/s:
Absorption of moisture.Internal stress relaxation after
compaction.Excessive coating material
concentration.
Adjust the coating
solutionconcentration.
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5. Twinning
Two or more tablets stickingtogether.
Cause/s:Inefficient drying.
Higher rate of application ofcoating solution.
Choosingappropriate shaped
tablets.
Controlling the
drying and rate ofmovement of pan.
Adjusting the
coating solutionconcentration.
6. Blooming
or Hazing
The polish of the product to
take on a fogged appearance.Cause/s:
High temperature duringformulation.
Exposure to high humidityconditions.
Controlling humidity
conditions.
Formulationtemperature
monitoring.
7. Bridging
or Filling
Occurs in tablets consisting
monogram or bisection.Bridging - coating shrinking or
pull away.
Fillingtoo much filling orthereby narrowing.
Cause/s:Improper application of the
solution.Poor design of the tablet
embossing.
High coating viscosity.High percentage of the solids in
the solution.Improper atomization pressure.
Control of spraying
of coating solution.
Soft edged font for
monogram.Atomization control
Concentration of
coating material.
8. Soft
tablets
The tablets are susceptible to
hydrolysis will develop softnature. Improper storage.
Mainly observed inpolymer/coated tablets.
Cause/s:
Lack of drying will enhancethe softness. Granulation
particles will completely freefrom moisture by keeping todrying
condition properly.
Soft tablet will form
initiate/basis for sticking orpicking defects.
Use of lubricant thatimpart waxy nature.
Application of low
compactionpressure. The
strength of bond isweakened across
granules.
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9. Orange
peel effect
Coating texture that resemblesthe surface of an orange.
Before drying causes a bumpyor orange peel effect on the
coating.
Causes/s:High atomization pressure in
combination with spray rates.
Too rapid drying.High solution viscosity.
Thinning the
solution with
additional solvent.
Controlling thedrying procedures.
10.Color
variation
Variation in the proposed color
for coating.Cause/s:
Improper mixing.Uneven spray pattern.Insufficient coating.
Unevenness of the surface ofthe sub-coating.
Using lake dyes.Go for geometric
mixing.
Use mild drying
conditions.
11.
Lamination
Occur upon storage period,
or soon after compression.
Cause/s:
Air entrapment betweenlayers of tablet.
Low levels of binding agent.
Improving lubricant
concentration.
Change the method ofgranulation.
By direct compressiontechnique it is preventedto some
extent.
Use always dry material
(feed).
12.Protracted
disintegration
Disintegration time is
extended in tablet.
Cause/s:
Use of high compression onpunches.
Incorporation of lubricant in
excess quantity.
Overcome by usingproper suitable surfactant
concentration.
Addition of more
concentration of bindingagent.
Too low compression
also favors extenddisintegration time.
