Nikkalite® Dewtect-S is durable transparent self adhesive sheeting with a hydrophilic surface coating which combats dew formation allowing normal retroreflectivity to occur. The sheeting is suitable for application to the surface of Nikkalite® Crystal grade and Ultralite retroreflective sheetings.
Application should only be undertaken during the manufacture of new signs and as the final application process through a wide width application roller in the sign shop.
The effective performance life of Dewtect-S dew resistant sheeting is 7 years for signs installed in the UK or Ireland. The sign face will not discolour or fade as the Dewtect-S properties decrease and the sign will eventually revert to a normal sign face with a clear overlay sheeting which will continue a form of surface protection. In certain daylight conditions a slight discoloration or matting of the surface may be visible. This is a characteristic of the hydrophilic coating and not an indication of a defect.
In humid conditions, dew forms on hydrophobic surfaces where high surface energies allow the water droplets to remain. Hydrophilic coatings reduce surface energies and a membrane forms on the surface of the Dewtect sheeting, dew is unable to remain on the surface as the hydrophilic properties alter the contact angle of the water droplets causing the droplets to flatten and form a membrane and retroreflectivity is restored to normal levels.
As dew starts to form and water droplets collect reflectivity is reduced, a sign not covered with DEWTECT -S overlay film will continue to lose reflectivity but a sign which is protected will recover and maintain a high level of retroreflectivity. DEWTECT-S may be applied to Nikkalite Crystal™ grade microprismatic or Ultralite Class ref 2 sheeting. Nikkalite DEWTECT-S overlay also assists in keeping the sign face clean. The hydrophilic surface coating and rain fall act to loosen and remove surface contamination including carbon deposits offering self-cleaning properties.