What will you gain?
1.9.2 Aspects of tablet coating
1.9.3 Basic principle of tablet coating
1.9.4 Type of tablet coating process
18.104.22.168 Sugar coating
22.214.171.124 Film coating
126.96.36.199 Enteric coating
188.8.131.52.1 Enteric sugar coating
184.108.40.206.2 Enteric film coating
220.127.116.11.3 Controlled release coating
18.104.22.168 Specialized coating
22.214.171.124.1 Compressed coating
126.96.36.199.2 Electrostatic coating
188.8.131.52.3 Dip coating
184.108.40.206.4 Vacuum film coating
1.9.6 Processing parameters
Coated tablets are defined as "tablets covered with one or more layers of mixture of various substances such as natural or synthetic resins ,gums ,inactive and insoluble filler, sugar, plasticizer, polyhydric alcohol ,waxes ,authorized colouring material and some times flavoring material .
Coating may also contain active ingredient. Substances used for coating are usually applied as solution or suspension under conditions where vehicle evaporates.
i) Avoid irritation of oesophagus and stomach
ii) Avoid bad taste
iii) Avoid inactivation of drug in the stomach
iv) Improve drug effectiveness
v) Prolong dosing interval
vi) Improve dosing interval
vii) Improve patient compliance
i) Reduce influence of moisture
ii) Avoid dust formation
iii) Reduce influence of atmosphere
iv) Improve drug stability
v) Prolong shelve life
i) Avoidbad taste
ii) Improve product identity
iii) Improve appearance and acceptability
The principle of tablet coating is relatively simple. Tablet coating is the application of coating composition to moving bed of tablets with concurrent use of heated air to facilitate evaporation of solvent.
Basic principles involve
i) Insulation which influences the release pattern as little as possible and does not markedly change the appearance.
ii) Modified release with specific requirement and release mechanism adapted to body function in the digestive tract
iii) Colour coating which provides insulation or is combined with modified release coating.