Tablet Bed temperature

what should be the tab bed temp in case of aqueous coating?

45-55 °C

its very high.
Tab bed temp 37_43 is enough.

sir plz explain meabout aqous coating

on the basis of solvent used coating is classified classified into three types
Aqueous = solvent is water
organic solvent= solvent is IPA,methanol etc
Hydroalcholic(aqueous+organic)=solvent is water+IPA etc
For operator and enviornment safety aqueous is prefered.

what is pore size of perforations in coating pan?

usualy 2.7 to 3.0 mm

Is there any reason behind that?

not special i think.

To have proper balance between inlet air and outlet/exhaust air.
and for improvised drying.


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Is there any regulation b/w inlet and outlet temperature?

it depends upon coating type used

Can you give me a general idea

For aqueous coating inlet temp is usually set at 55-60 and bed temp is 38-40 and outlet temp is 44,45.
for organic solvent inlet is set at 40_45
bed is 35_37 and outlet is 35_38


bacically coating is art and it depend upon present conditions in which you r working and coating equipment so according to conditions and coating machine we have to change parametrs to keep our product stable

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What is the importance of tablet bed temperature during coating?

tab bed temp is imp to prevent coating defects

Bed temperature is not an independent parameter it depends on inlet temperature and spray rate so we can not fix the same bed temperature for all products.Their are so many factors which decides inlet temperature and spray rate like;

1.Coating system: Aqueous/Non aqueous.

2.Hardness of tablet and nature of drug product.

3.Size and surface ( score or embossed ) of Tablet

4.Occupancy in Pan etc.
Is that right?

yes obviouslu it is not independent it depends uopn inlet temp.
if high inlet high bed temp.
also dependent uopn aqueous and non aqueous.
for aqueous low rise and for non aqueous high rise.
Depend upon product nature but not on hardness.
also depeng on shape and size in term of occupncy

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Tablet bed temperature is important during coating because it bed temp. increase from normal tolerance temperature then tablets coat melt down. Then one tablet attached with another one.

If temperature is below coating drying temperature then coating solution may drain from coating bed.
Another thing I read