- incipient wetness
- Condition when just enough liquid has been added to a porous solid to just fill all the pore. If more liquid is added to the mixture, it coats the outer surface, changing the appearance from dull to glistening. On drying, catalyst materials added in an incipient wetness impregnation will deposit in the pores rather than on the outer surface.
Petroleum refining glossary. 2013.