Thermography or Verco printingThermography is a post print process. Thermography machines are normally in 3 sections connected via a conveyor.
The sections’ tasks are as follows:
- Powdered polymer is applied to the litho printed sheet. The areas destined for raised printing are printed with inks that remain wet during the application of powder.
- Then a gentle vacuuming removes any excess powder from the dry areas.
- The printed sheets are then conveyed into a radiant oven system for a period of about 3 seconds. The required temperature for these brief seconds is 480 – 704 degree’s centigrade.
Following this 3rd stage the product is cooled rapidly by some convection means.
Of course this process can be carried out manually. It is then termed a “Manual powdering process”. The substrate is dipped into the polymer powder and then tilted back and forth and tapped in a vertical position to remove the excess powder. Then either by a hand held heat gun or by being fed thru a radiant heat source like a grill the raised printing effect can be processed. This latter method is ideal for hobbyists.
Raised printing or thermography has common application on business cards, greeting cards, braille text, wedding invitations, letterheads and certificates.