Tablet manufacturing process basics

1. Presented By
K.TRIDEVA SASTRI

2. Introduction
• Tablets are solid dosage forms consisting of active
ingredient(s) and suitable pharmaceutical
excipients.
• They may vary in size, shape, weight, hardness,
thickness, disintegration and dissolution
characteristics, and in other aspects.
• They may be classyfied, according to the method
of manufacture, as compressed tablets or molded
tablets.

3. • Traditionally, tablets have been made by
granulation, a process that imparts two primary
requisites to formulate: compactibility and
fluidity.
• Both wet granulation and dry granulation
(slugging and roll compaction) are used.
• Numerous unit processes are involved in making
tablets, including particle size reduction and
sizing, blending, granulation, drying, compaction,
and (frequently) coating.

4. Advantages
• They are unit dosage forms hence precise
dose delivery and least content variability.
• They are economic amongst oral dosage
forms.
• They are lightest and most compactable.
• They are easily packed and equally
economical.
• Product identification is simpler.

5. • Self administration by the patient can be
achieved.
• They lend themselves to certain release profile,
like Enteric, sustained release products.
• They have best combined properties of chemical,
mechanical and microbiologic stability of all the
oral forms.

6. Disadvantages
• Some drugs resist compression into dense compacts
• Drugs with poor wetting, slow dissolution, intermediate
to large dosages may be difficult or impossible to
formulate and manufacture as a tablet that provide
adequate or full drug bioavailability
• Bitter taste drugs, drugs with an objectionable odor, or
sensitive to oxygen or moisture may require
encapsulation or entrapment prior to compression or the
tablets may require coating

7. Types of tablets
• Compressed Tablets
• Sugar coated Tablets
• Film coated Tablets
• Enteric coated Tablets
• Effervescent Tablets
• Chewable Tablets
• Dispersible Tablets
• Sustained release Tablets
• Multilayer Tablets
• Sublingual Tablets
• Troches
• Buccal Tablets
• Implant Tablets
• Hypodermic Tablets
• Solution Tablets
• Vaginal Tablets

8. Tablet design and Formulation
The main objective of the design and
manufacture of the compressed tablets,
• deliver oral correct amount of the drug, in
proper form, at proper time and in desired
location and to have its chemical integrity
protected to that point.

9. Characteristics of ideal tablet
• It should be elegant.
• It should have strength to withstand
mechanical shocks during various processes.
• It should have physical and chemical stability.
• It should be able to release medicinal agents
in predictable and reproducible manner.

10. Formulation components
• Formulation components attribute towards:
• Provide essential manufacturing technology
functions (Binders, lubricants, glidants)
• Modify drug release (Disintegrants, polymers)
• Enhance stability (Antioxidants)
• Enhance patient acceptance (Flavors, Colors)
All non drug components of a formula are termed
as EXCIPIENTS.

11. Characteristics of ideal Excipient
• They must be nontoxic and acceptable to regulatory
agencies.
• They must be commercially available in acceptable grade
• There cost must be low
• They must be physiologically inert
• They must be physically & chemically stable by themselves
& in combination with the drugs.
• They must be free from all microbial contamination.
• They do not alter the bioavailability of drug.
• They must be color compatible.

12. Excipients
• Diluent
• Binder and adhesive
• Disintegrents
• Lubricants and glidants
• Coloring agents
• Flavoring agents
• Sweetening agents

13. Diluents
Diluents are fillers used to make required bulk of
the tablet when the drug dosage itself is
inadequate to produce the bulk. Secondary
reason is to provide better tablet properties
such as improve cohesion, to permit use of
direct compression manufacturing or to
promote flow.

14. Commonly used tablet diluents
• Lactose‐anhydrous and spray dried lactose
• Directly compressed starch‐Sta Rx 1500
• Hydrolyzed starch‐Emdex and Celutab
• Microcrystalline cellulose‐Avicel (PH 101and PH 102)
• Dibasic calcium phosphate dehydrate
• Calcium sulphate dihydrate
• Mannitol
• Sorbitol
• Sucrose‐ Sugartab, DiPac, Nutab
• Dextrose

15. Binders and Adhesives
Binders promote the adhesion of particles of the
formulation. Such adhesion enables
preparation of granules and maintains the
integrity of the final tablet.

16. Commonly used tablet binders
• Acacia, tragacanth‐ Solution for 10‐25% Conc.
• Cellulose derivatives‐ Methyl cellulose, Hydroxy propyl
methyl
• cellulose, Hydroxy propyl cellulose
• Gelatin‐ 10‐20% solution
• Glucose‐ 50% solution
• Polyvinylpyrrolidone (PVP)‐ 2% conc.
• Starch paste‐10‐20% solution
• Sodium alginate
• Sorbitol

17. Disintegrants
The breakup of the tablets to smaller particles is
important for dissolution of the drug & subsequent
bioavailability. Disintegrators promote such breakup. To
rupture or breakup of tablets, disintegrating agents
must swell or expand on exposure to aqueous solution.
Thus, the most effective disintegrating agents in most
tablet systems are those with the highest water uptake
property. In general, the more hydrophilic, the better
disintegrating agents are therefore highly hydrophilic.

18. Commonly used tablet disintegrants
• Starch‐ 5‐20% of tablet weight.
• Starch derivative – Primogel and Explotab (1‐8%)
• Clays‐ Veegum HV, bentonite 10% level in colored tablet
only
• Cellulose
• Cellulose derivatives‐ Ac‐ Di‐Sol (sodium carboxy methyl
• cellulose)
• Alginate
• PVP (Polyvinylpyrrolidone), cross‐linked

19. Lubricants and Glidants
• Lubricant is a substance capable of reducing or
preventing friction, heat, and wear when
introduced as a film between solid surfaces. It
works by coating on the surface of particles, and
thus preventing adhesion of the tablet material to
the dies and punches.
• Glidants are intended to promote flow of
granules or powder material by reducing the
friction between the particles.

20. Commonly used tablet lubricant and
Glidants
• Lubricants‐ Stearic acid, Stearic acid salt ‐
Stearic acid, Magnesium stearate, Talc, PEG
(Polyethylene glycols), Surfactants
• Glidants‐ Corn Starch – 5‐10% conc., Talc‐5%
conc., Silica derivative ‐ Colloidal silicas such
as Cab‐O‐Sil, Syloid, Aerosil in 0.25‐3% conc.

21. Coloring agents
(1) Masking of off color drugs
(2) Product Identification
(3) Production of more elegant product
All coloring agents must be approved and certified by
FDA. Two forms of colors are used in tablet preparation
– FD &C and D & C dyes.
These dyes are applied as solution in the granulating
agent or Lake form of these dyes. Lakes are dyes
absorbed on hydrous oxide and employed as dry
powder coloring.

22. Commonly used tablet colorants
• FD & C yellow 6‐sunset yellow
• FD & C yellow 5‐ Tartrazine
• FD & C green 3‐ Fast Green
• FD & C blue 1‐ Brilliant Blue
• FD & C blue 2 ‐ Indigo carmine
• D & Cred 3‐ Erythrosine.
• D & Cred 22 – Eosin Y

23. Flavors and sweeteners
Flavoring agents: For chewable tablet‐ flavor oil are used
Sweetening agents:
For chewable tablets: Sugar, mannitol.
• Saccharine (artificial): 500 time’s sweeter than sucrose
• Disadvantage: Bitter aftertaste and carcinogenic
• Aspartame (artificial)
• Disadvantage: Lack of stability in presence of moisture.

24. Tablet Manufacturing
• Granulation Technology

25. Chlisonator Roller compactor

26. Wet Granulation Mechanism
There are five primary bonding
mechanisms between particles:
• Adhesion and cohesion forces in the
immobile liquid films between
individual primary powder particles;
Surface tension and negative
capillary pressure
• Interfacial forces in mobile liquid
films within the granules; Coalesce
• Capillary stage interfacial forces
• The formation of solid bridges after
solvent evaporation;
• Attractive forces between solid
particles;
• Mechanical interlocking.
.

27. Diosna Granulator

28. Tablet compression Machines
Tablets are made by compressing a formulation containing a
drug or drugs with excipients on stamping machine called
presses. Tablet presses are designed with following basic
components:
1) Hopper for holding and feeding granulation
2) Dies that define the size and shape of the tablet.
3) Punches for compressing the granulation within the dies.
4) Cam tracks for guiding the movement of the punches.
5) A feeding mechanism for moving granulation from hopper
into the dies

31. Compression cycle of rotary press

32. Evaluation of Tablets
1. General Appearance: The general appearance of a tablet, its identity and general
elegance is essential for consumer acceptance, for control of lot‐to‐lot uniformity and
tablet‐to‐tablet uniformity. The control of general appearance involves the
measurement of size, shape, color, presence or absence of odor, taste etc.
2. Size & Shape: It can be dimensionally described & controlled. The thickness of a tablet
is only variables. Tablet thickness can be measured by micrometer or by other device.
Tablet thickness should be controlled within a ± 5% variation of standard value.
3. Unique identification marking: These marking utilize some form of embossing,
engraving or printing. These markings include company name or symbol, product code,
product name etc.
4. Organoleptic properties: Color distribution must be uniform with no mottling. For visual
color comparison compare the color of sample against standard color.
5. Hardness and Friability: Tablet requires a certain amount of strength or hardness and
resistance to friability to withstand mechanical shakes of handling in manufacture,
packaging and shipping. Hardness generally measures the tablet crushing strength

34. 6.Friability:
Friability of a tablet can determine in laboratory by Roche friabilator.
This consist of a plastic chamber that revolves at
25 rpm, dropping the tablets through a
Distance of six inches in the friabilator, which
is then operate for 100 revolutions. The
tablets are reweighed. Compress tablet that
lose less than 0.5 to 1.0 % of the Tablet weigh
are consider acceptable.

36. Drug Content and Release
• Uniformity of Weight of Single-Dose Preparations
Weigh individually 20 units selected at random or, for
single dose preparations in individual containers, the
contents of 20 units, and calculate the average weight.
Not more than two of the individual weights deviate
from the average weight by more than the percentage
shown in the table and none deviates by more than
twice that percentage

37. Dosage form Average weight
Percentage
deviation
Uncoated and film- coated tablets 80 mg or less 10
More than 80 mg but less than 250
mg
7.5
250 mg or more 5
Capsules, granules and
powders (single-dose)
Less than 300 mg 10
300 mg or more 7.5
Powders for parenteral Use More than 40 mg 10
Pessaries and
suppositories
All weights 5

38. Uniformity of Content for Single-Dose
Preparations
The test for uniformity of content of single-dose preparations is based on the
assay of the individual contents of active substance(s) of a number of
single-dose units to determine whether the individual contents are within
limits set with reference to the average content of the sample.
• Method. Determine the content of active ingredient(s) in each of 10
dosage units taken at random using the method given in the monograph
or by any other suitable analytical method.
• Acceptance limits
The tablets comply with the test if not more than one of the individual values
thus obtained is outside the limits 85 to 115% of the average value and
none is outside the limits 75 to 125% of the average value. If two or
three of the individual values are outside the limits 85 to 115% of the
average value and none is outside the limits 75 to 125%, repeat the
determination using another 20 tablets. The tablets comply with the test if
in the total sample of 30 tablets not more than three of the individual
values are outside the limits 85 to 115% and none is outside the limits 75
to 125% of the average value.

39. Disintegration

40. Dissolution
• Two objectives in
development of invitro
dissolution tests are to
show
1. That drug release is as
close as possible to
100% , and
2. That the rate of drug
release is uniform batch
to batch.

41. Acceptance Limits according to USP

42. Processing Problems
• Capping and Lamination
1. Capping and lamination have in the past been
attributed to air entrapment during compression
process, and does not escape until compression
force is removed.
2. However researches revealed that Capping and
lamination are due to deformational properties
of the formulation.

43. THE CAUSES AND REMEDIES OF CAPPING RELATED TO
‘FORMULATION’ (GRANULATION)
Sno CAUSES REMEDIES
1 Large amount of fines in the granulation
Remove some or all fines through 100
to 200 mesh screen
2 Too dry or very low moisture content
(leading to loss of proper binding action).
Moisten the granules suitably. Add
hygroscopic substance e.g.: Sorbitol,
Methylcellulose or PEG-4000.
3 Not thoroughly dried granules. Dry the granules properly.
4
Insufficient amount of binder or improper
binder.
Increasing the amount of binder OR
Adding dry binder such as pre-gelatinized
Starch, Gum acacia, powdered Sorbitol,
PVP, hydrophilic Silica or powdered Sugar.
5 Insufficient or improper lubricant. Increase the amount of lubricant or
change the type of lubricant.
6 Granular mass too cold to compress firm. Compress at room temperature.

44. THE CAUSES AND REMEDIES OF CAPPING RELATED TO
‘MACHINE’ (DIES, PUNCHES AND TABLET PRESS)
Sr. No. CAUSES REMEDIES
1. Poorly finished dies Polish dies properly. Investigate other steels or other materials.
2. Deep concave punches or beveled-edge faces of punches. Use flat punches.
3. Lower punch remains below the face of die during ejection. Make proper setting of lower punch during ejection.
4. Incorrect adjustment of sweep-off blade. Adjust sweep-off blade correctly to facilitate proper ejection.
5. High turret speed. Reduce speed of turret (Increase dwell time).

45. Picking and sticking
• Picking is a term used to describe the surface
material from a tablet that is sticking to and
being removed from the tablet’s surface by a
punch.
• Sticking refers to tablet material adhering to
die wall.

46. THE CAUSES AND REMEDIES OF PICKING RELATED TO
MACHINE (DIES, PUNCHES AND TABLET PRESS)
Sr. No. CAUSES REMEDIES
1. Rough or scratched punch faces. Polish faces to high luster.
2.
Embossing or engraving letters on punch faces such as
B, A, O, R, P, Q, G.
Design lettering as large as possible.
Plate the punch faces with chromium to produce a
smooth and non-adherent face.
3. Bevels or dividing lines too deep. Reduce depths and sharpness.
4. Pressure applied is not enough; too soft tablets. Increase pressure to optimum.

47. THE CAUSES AND REMEDIES OF STICKING RELATED TO
FORMULATION (GRANULATION)
Sr. No. CAUSES REMEDIES
1. Granules not dried properly.
Dry the granules properly. Make moisture analysis to
determine limits.
2. Too little or improper lubrication. Increase or change lubricant.
3. Too much binder
Reduce the amount of binder or use a different type of
binder.
4. Hygroscopic granular material.
Modify granulation and compress under controlled
humidity.
5. Oily or way materials Modify mixing process. Add an absorbent.

48. Sr. No. CAUSES REMEDIES
1.
A coloured drug used along with colourless or white-
coloured excipients.
Use appropriate colourants.
2.
A dye migrates to the surface of granulation while
drying.
Change the solvent system,
Change the binder,
Reduce drying temperature and
Use a smaller particle size.
3.
Improperly mixed dye, especially during ‘Direct
Compression’.
Mix properly and reduce size if it is of a larger size to
prevent segregation.
4. Improper mixing of a coloured binder solution.
Incorporate dry colour additive during powder blending
step, then add fine powdered adhesives such as acacia
and tragacanth and mix well and finally add granulating
liquid.
Mottling
Unequal distribution of color on a tablet, with
light or dark spots.

49. Weight Variation
The weight of tablet being compressed is
determined by the amount of granulation in the
die prior to the compression. Therefore anything
that can alter the die filling process can alter
tablet weight.
1. Granule size and size distribution before
compression,
2. Poor mixing and Poor flow,
3. Punch variation

50. Hardness variation
Hardness variation is a problem that has
the same causes as weight variation,
hardness depends on weight of the
material and space between the punches
at the moment of compression. If volume
of the material or distance between
punches varies, hardness is likewise
inconsistent.

51. Double Impression
This involves only punches that have monogram
or other engraving on them.
Mostly in when two compression stages to
compress a tablet.