Coating agents

[Ian Grant]

3 years, 1 month ago #2417

How does a coating agent work?

[Forum Administrator]

3 years, 1 month ago #2432

To act as an anticaking agent, an additive has to interfere with the caking mechanism. It can do this in one or more of several ways:
• Prevention of wetting across the contact points of the granules.
• Diffusion of the crystallising phase over the granule surface.
• Nucleation of small fine crystals during dissolution/re-crystallisation processes.
• Modification of crystal structure and size of crystals formed during dissolution/re-crystallisation processes.
• Inhibition of dissolution/re-crystallisation processes.
• Spreading of the liquid film over the granule surface, promoted by reduction of surface tension, thus reducing the formation of droplets of liquid at the granule surface, as well as reducing condensation in the capillary formed at the contact points.
• Reduction of formation of contact areas.
• Reduction of tensile strength of the bond between the granules.
• Removal of moisture from the granule surface by absorption.
• Protection from ambient humidity.
For more details, see IFS Proceedings 453.