An Overview of Thermographic Printing
Thermographic printing is a popular technique which has become widely used on everything from wedding invitations to greetings cards and beyond. What sets thermographic printing apart from other methods is the fact that printers can use the process to make elements of the image or the font almost 3D whilst maintaining a natural aesthetic.
An Introduction to Thermographic Printing
British Letterpress have stated that whilst the origins of thermography are unclear, it is known to date back to when engraving was the most commonly used method of font styling. Originally, engraving would involve using a copper or zinc metal plate. The grooves would then be filled with the desired ink before being transferred to paper using high pressure. The effect ended up being a print which was slightly raised.
Although the effect was aesthetically pleasing, new plates were needed for every project, meaning it took up a great deal of time. Although this method is still used, it is one of the most costly. Thermography was born out of a desire to speed the process up and cut costs. By using the moveable type printing presses, thermography was able to save customers and printers significant amounts of money.
How does it work?
Thermography is the combination of three straightforward processes. The first process is the application of the thermographic powder, occasionally referred to as embossing powder. The powder, which is made from plastic resins, is coated on the page, and attaches itself to any wet ink.
The next stage begins with vacuuming away any excess powder, meaning only the inked parts which are coated remain. Finally, once the excess has been removed, the transforming process can begin. This is where the substrate gets moved through an oven and is exposed to temperatures ranging between 900 and 1300C. The exposure to the temperature lasts for no more than a few seconds in total.
During the time in the oven, the rise in temperature causes the powder elements to melt, creating the shiny and raised effect many consumers will be familiar with.
What are the benefits?
The benefit of thermographic printing is mainly its visual appeal. For printers it's an inexpensive method, especially when compared to engraving, and it gives a more natural look than other printing options such as Spot UV printing. Those who use thermographic printing tend to use it on items such as greetings cards and invitations. Raised elements in the picture or font can really make a card or invitation stand out, and the natural feeling of the finished product adds a touch of sophistication.
The key points to remember about thermographic printing is that it is much faster than engraving. The three simple processes which are used in thermographic printing can be quickly summarised, beginning with the powder stage where the powder is applied to wet ink on the page. This is followed by vacuuming to remove the excess before it heads into the oven for no more than 2-3 seconds to create the familiar, shiny appearance. In short, thermographic printing helped to revolutionise printing and is now commonly used throughout the world.