Thermography printing is commonly known as poor man's engraving, thermography produces raised printing similar in appearance to engraving but using a different process. In thermography, a special powder is added to the ink printed on the paper. The printed piece is heated and the powder and ink mixture dries to form a raised effect on the paper. [1]

Thermography printing

Thermographic printing refers to a way of printing or means to create images on a sheet of paper which rely on heat. There are two types of thermographic printing: thermal printing (or the simple one) and thermal ink transfer printing (or the most complex one). The former is where the paper is coated in a special chemical which changes color when it comes in contact with heat. This method is usually used in old models of fax machines and in most cash register-printing receipts. On the other hand, the latter melts a coating of ribbon so that the text remains on the material where the print is applied. This method is used usually in bar codes and used to print plastic labels on
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Thermography printing is a type of printing process which uses heat to melt powdered ink onto the paper, resulting in a raised effect. It is also known as thermographic printing, offset thermography and raised printing.
plastic containers. [2]

Thermography printing references

As compared to the traditional or to the usual way of printing things, having a touch of thermographic printing on your paper makes it a bit morespecial. Why? Simply because the end result will be a text that raises itself from all the other texts in your paper. Having this argument said, thermographic printing is visible in business cards, letterheads and invitations. To add to the ongoing list, thermographic printing is also used in our graduation diploma, which is an attractive alternative to the more costly engraving option.Although this kind of printing is a bit unknown to men, this is quite expensive because a new template must be made for every design. Meaning, you cannot “recycle” the old templates which you have used. However expensive this method can be, there are already lots of printing firms that offers this kind of printing. [3]

Thermography as raised print process

Thermography is also the name of a post print process that is achieved today using traditional printing methods coupled with thermography machines. Thermography machines consist of three sections connected by a through conveyor.
The first section applies powdered polymer to the entire sheet followed by vacuum removal of excess powder from non-imaged and dry ink areas. The areas selected for raised printing are printed with inks that do not contain dryers or hardeners so that they remain wet during the application of powder. This ink is dried or hardened later during the heating process.
The second section of the process is a vacuum system that removes excess powder from uninked areas of the substrate. [4]
The third section of the process conveys the product through a radiant oven where it is exposed to temperatures of 900 to 1300 degrees Fahrenheit.[5]
The heating process takes on the order of 2.5 to 3 seconds. The substrate (usually paper) has a peak in IR absorption at the wavelength used. Through conduction from the paper, the powder temperature rapidly increases and starts melting. When the process is correctly adjusted, the center of the largest filmed areas reach sufficient quality level as the product exits the heater. The melted ink then solidifies as the product cools.
This process is sometimes produced using manual powdering. The substrate with the wet ink areas selected for the effect are dipped into the powdered polymer. The sheet is tilted back and forth, rolling the powder across the image. The excess powder is removed by raising the substrate to a vertical position and lightly tapping the back. The powdered sheet is then fed into a radiant heating system as above at a speed to achieve a quality filming. In the case of craft applications, the powder is then melted using a heatgun that blows hot air.
It is commonly used on wedding invitations, letterheads, business cards, greetings cards, gift wrap, packaging and can also be used to print braille text. It is even sometimes used indiploma printing as an attractive alternative to the more expensive engraving option.


Video demonstrating heat raised printing.
  1. ^
    http://desktoppub.about.com/cs/printing/g/thermography.htm
  2. ^
    http://www.thermographyprinting.net/
  3. ^ http://www.thermographyprinting.net/
  4. ^
    http://glossary.ippaper.com/default.asp?req=knowledge/article/154&catitemid=24
  5. ^
    http://www.thermographers.org/thermupd.asp