Introduction: The SPI Supplies Spray Maker™ Duster Valve was designed for those who have the need to make a micro-aerosol from a liquid, mainly for microscopy applications. Persons wanting to end up with a fine particle (usually colloidal or nano size) dispersion on a solid surface such as for analysis by SEM or even TEM, prefer this kind of approach since it limits surface tension forces from their thermodynamically driven propensity to agglomerate because of surface tension forces.
If there is a fine dispersion of individual droplets on a surface, as the liquid evaporates, while agglomeration can still occur, what does occur is confined to that agglomeration that occurs within a single micro droplet.
Principle of operation: This specially designed valve, based on the Bernoulli principle, will disperse any fluid onto a substrate as a fine uniform dispersion of micro aerosol droplets (each of which presumably contains suspended particulates). Reproducible amounts of the liquid can be drawn into special capillary tubes, inserted into the plastic pipette and dispersed without danger of coagulation or droplet formation.
Principle Applications: Already mentioned, is the application involving the dispersion of colloidal or nano size particulates for examination by some form of microscopy, either SEM or TEM or even at times, LM. It is also used to apply conductive polymer coatings on samples destined for examination by SEM. It has also been used as a means of finely dispersing in a uniform layer a vacuum grease (such as one of the Apiezon® high vacuum greases) that has been dissolved in an organic solvent such as heptane.
What one needs to get started: The SPI Supplies Spray Maker™ Duster Valve is mandatory as well as the special capillary tubes. And of course, a supply of the SPI Supplies "Two-in-One" Easy Dusters is also needed. Also needed are plastic pipettes.
