Robnor ResinLab MP313C Varnish 5Lt Can

MP313C is a one component, air-drying solvent-based varnish. MP313C has been designed for application by dipping. Best results will be obtained by use of PCB dipping machine, such as that produced by Robnor Resins. Coating of suitable, even thickness requires a slow steady withdrawal from the dipping bath - thus difficult to achieve by hand dipping. If the PCB has a number of large standoff units this may necessitate a draining step in the dipping cycle. The thickness of varnish applied may be varied with the limits by altering the speed of withdrawal from the bath - the slower the withdrawal, the thinner the coat.

Attempting to apply too thick a coat in one stage may result in sagging or wrinkling. If a thick coat is required, this is best achieved via two thin coats - the first coat must be thoroughly cured before the second is applied. In all cases before the application of the coating thorough cleaning and drying is essential. Immediately before PCB assemblies are conformally coated all flux residues and other surface contaminants should be removed. If practicable a cleanliness level better than 1.5-gNaCl/cm2 salt weight equivalents should be achieved. The material will dry to give a tough hard-working insulating varnish when cured at room temperature; however, superior properties will be obtained if cured at elevated temperatures.

A suggested cure schedule is 8hours @ 80°C. This material is normally supplied at a dilution that should give a coating thickness in the region of 35¬m, however this can be altered by changes to application procedures. In some applications thinning of the material may be required e.g. spraying. In such instances TS109 Thinners should be used.