During paint manufacture, product can congeal and form lumps within batch. These formations drastically reduce the quality of the paint when applied to an object walls and can even damage equipment. For example, trying to pull coagulated paint through a spray gun will cause it to block and possibly burst the pressure system.
To filter out the gels that can sometimes form, bag filtration is applied due to the ability for them to operate under the wide spectrum of viscosities that comes with the paint sector. This stage is placed directly before the filling stations, where the tins of paint are sealed. This is to ensure the paint has no opportunity to become spoiled before it is packaged to leave the production facility.