ThermoEmbossing™ is a process that allows customers who produce foil fusing to create a registered foil embossed effect on certain papers without an embossing die. In addition to creating a foil embossed image effect, background textures as well as graphics and security text can be added within the foil fused image areas.
A color laser printer that can print with CMYK is required to create a ThermoEmbossed™ image. During pre-press, the flat foil image areas are normally specified as a 75 to 90% black toner image (ideally, you should apply the minimum amount of toner required to achieve a full foil transfer to the image area and this can vary with different papers, foils and printers). The embossed foil areas of the image are specified as a “rich” black (100% CMYK) toner image area(s). If your printer provides control over toner lay down (density), we recommend imprinting the rich black image areas with maximum toner.
As sheets are printed on the laser printer, it will be visually obvious where there is a single layer of black toner (flat image areas) and the thicker, darker areas that have been printed in rich black.
As both toner thickness areas are applied in a single pass through the laser printer, the “flat” and “embossed” areas are perfectly registered.
After printing, sheets are run through a foil fuser to apply foil to the toner image areas. While foil will adhere to all toner image areas, the rich black portion of the image area will appear embossed.
While the ThermoEmbossing™ process is clearly visible with most fusing foils, it really stands out when a bright finish metallic foil is used. Adding a border around the foil fused area containing ThermoEmbossing™ also enhances the effect. Very thin lines of rich black toner or vary narrow spacing between rich black toner lines are not recommended.
A 9600 Okidata printer was used during the development of the ThermoEmbossing™ process. There is a learning curve involved in successfully using this process but once the basic parameters are understood, the effects that can be created are amazing.
The ThermoEmbossing™ process does not work well with all papers. Smooth, coated papers give the highest “embossed“ effect. Uncoated stocks do not work well because the toner can melt down into the paper during foil fusing, flattening out the embossed effect.
It is interesting to note that foil fused and/or ThermoEmbossed™ sheets are compatible with thermography. Sheets are first foil fused and/or ThermoEmbossed™, then printed using an offset press or digital duplicator, then thermographed. During our tests, the thermography powder did not adhere to the foil and the thermography machine heat tunnel did not affect the foil fused image areas.
ThermoEmbossing™ is also compatible with the Freedom Foil Process when using smooth finish papers. Sheets that have been foil fused using the Freedom Foil Process are NOT compatible with thermography.
One limitation of foil fusing has always been that the process can only produce a flat foil effect. With the introduction of the ThermoEmbossing™ process, foil fusing can now provide depth and texture to foil fused image areas on certain papers. Currently, ThermoEmbossing™ is not compatible with the HSFF™ (high speed foil fusing™) process.