Preparation and Application of Microcapsules

Finally, active products are permanently encapsulated in order to permit the mixing of incompatible products. Compatibihty and protection are somewhat inter-related, and for a variety of applications both will apply. Classic examples are the phase-change materials (PCMs) these are permanently entrapped in their encapsulated forms, which means that the effect offered is not diminished throughout its period of use. 

Currently, many techniques are available for the preparation of microcapsules, though no single technique can be considered ideal . In view of the diversity and size of the microencapsulation field, the relevance of some techniques is outlined in Table 7.1 [2]. 

PAN coating Low-cost equipment Difficult to control, high skill level required 

Spray-drying Equipment and know-how widely available, versatile High equipment and operating costs, high temperatures, uses organic solvents 

Spray-cooling Solvent-free Low production volume 

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