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Mersad Berberović

Flat Printing vs. Thermographic Printing

It is not always easy to see by glancing at a printed document, but there are several different processes it may have gone through to achieve its final product. Each method provides an end result that is desirable for various needs. Two of the primary printing processes used in modern printing are flat and thermographic. Below we will discuss their different histories, processes, and results.

Flat Printing History
Flat printing, or lithography, is a process dating back to 1796. It was developed by German author Alois Senefelder as a cheap alternative for publishing theatrical works. When this process was first developed, artists and writers had to draw or write on limestone with oil, fat, or wax. After this, it was treated with acid and gum Arabic and left to dry. The areas that were etched into the stone began retaining water, and the artist then used oil-based into to cover them. The water repelled the ink and the ink stayed on the surface of the etching. Finally, the ink was transferred onto paper or another material.

Modern Flat Printing
Some pieces of fine art are still developed using the original method of flat printing, but most printing done with the flat printing process takes a more modern approach. As technology has advanced, so has the speed and efficiency available to this process. One newer method takes a polymer-covered image or writing and affixes it to an aluminum plate. It is then printed from the plate onto another medium, such as rubber, and finally published onto paper or another surface.

In a similar fashion, the other method, offset flat printing, uses printing plates that are covered with a photosensitive emulsion. The imprinted image (“negative”) is placed into this emulsion, and then exposed to ultraviolet light. It develops and creates a “positive” image. This modern offset flat print or offset lithography is used to produce almost all smooth, mass-produced print and graphics such as books, newspapers, maps, and posters.

The image or writing produced from the flat printing process is, as one would assume, flat. In other words, it is leveled with the surface of the paper. While it sounds simple, the final product of this process is still a crystal clear image, making it the best choice for designs with potential ink bleeds. This process will allow the mix of light and dark colors without worrying about them flowing together in an undesired manner. This process also eliminates the potential of melting or chipping.

Thermography History
The absolute history of thermography is not entirely clear. This raised printing method was developed in the early 1900s. It is credited to Fox Talbot, Carl Miller, and sometimes others. It is likely that each of them played a role in developing thermography into the process it is today.

At first, this method, which is described in depth below, was all done by hand. By 1915, the first machine was produced to complete the process automatically. It gained popularity as technology advanced over time, and it became even simpler. Today, it is a heavily utilized printing process with broad appeal due to the high-quality images it produces.

Thermographic Printing Process
Thermographic printing is similar to flat printing but adds dimension to the final product. When the ink is wet, a powder is applied to it. The product is then heated and the powder rises to create a textured and dimensional image. The heat helps the ink dry quickly for a speedy end result. The multi-dimensional thermographic image is visually appealing and thus is often used on wedding invitations, letterheads, business cards, greeting cards, gift wrap, diplomas, and packaging. Thermographic printing is also used to print braille text. This type of printing may be done manually or through an entirely automated system.

Some important design rules to keep in mind with thermography are:

  • The powder used in this process can be a clear matte or high gloss finish to produce whichever result is desired.
  • Thermographic printing must be single sided.
  • Type smaller than 6 points cannot be used with thermographic printing as blank spaces in letters and numbers will bleed and fill in.
  • Thinner fonts should be avoided with this type of printing.
  • One should avoid mixing small type with large solid colored areas on the same page.
  • Large solid printed areas should also be avoided as image shrinking is normal in this process and thus can cause distortion.
  • When printing stationery that is used in a laser printer or photocopier, the fuser in the machine may cause the resin to melt within and damage the device. Caution must be taken. However, if the thermography itself is completed with a laser, the powder is cured by UV light and then will be able to withstand high temperatures in a machine without damage.
  • Light colors do not work well with thermography because light colors cover less ink which gives less space for the powder to stick to. This would raise the type or image to different levels than dark colors.
  • The powder will stick to anything. Therefore caution must be exercised when touching the printed material with potentially oily hands.

Thermography Benefits
Thermography is an excellent printing option because it provides high-quality material at a low cost. The material produced is very similar to what the engraving process, which is the most distinct and perhaps most desired form of three-dimensional printing, would result in. The engraving process, however, is highly expensive. Additionally, it produces textured and vibrant colors with shine if desired. The results of a thermographic image or text are similar to those of one that is engraved but cheaper.

Conclusion
Flat (lithographic) and thermographic printing are both widely used options in the printing method. For everyday materials with ink flat to the surface, flat printing is likely the process that was used. Fancier products that have three-dimensional print and look somewhat nicer were probably printed using thermography. When making the choice, one must take into account the colors of ink they are using, the size of font or images, their budget, and the results they desire.