Benefits of Different Types of Drop-on-Demand Inkjet Printing

When it comes to inkjet printer models, each printer can fall into one of two categories: continuous inkjet (CIJ) and drop-on-demand (DOD). 

Continuous inkjet printers were developed and released first. Made to code products at high speeds for extended periods of time, CIJ printers appeared on the market during the 1950s, and today they remain a popular fixture in production lines around the world. The term “continuous inkjet printer” stems from their ability to create continuous streams of ink that enable prolonged high-speed marking. 

Drop-on-demand printers were introduced to the market in the 1980s, decades after CIJ machines were already popular. Although both printer categories are considered inkjet printers, they operate very differently. While CIJ printers maintain constant ink pressure to be prepared to mark materials when the need arises, DOD printers only pressurize ink when they are about to mark a package. 

Another major difference between these two classifications is how many technologies fall under their purview. As a term, “CIJ” specifically refers to one type of printer—the continuous inkjet printer. Conversely, “DOD” is a broad umbrella term that encompasses a number of printing technologies, including:

  • Thermal inkjet printers
  • High-resolution case coders
  • Valve jet printers

If you’re new to the world of drop-on-demand printers, read here to learn more about the different types of DOD technologies and their benefits.

Thermal Inkjet Printers

Commonly abbreviated to TIJ, thermal inkjet printers are one of the most popular industrial printing technologies available today. 

The “thermal” part of the name “thermal inkjet printer” refers to how these machines use heat to pressurize ink. Every TIJ printer is built with a series of heating elements adjacent to an ink cartridge slot. The heating elements increase the temperature of the liquid ink within the cartridge, causing a bubble to form. 

The pressure from the bubble forces the ink out of the printer’s nozzle and onto the substrate, creating the desired image or code. Afterward, the bubble collapses, creating a vacuum effect that restarts the entire process.

TIJ printers are popular for many reasons. For one, they are compact and often weigh only a few pounds. These small dimensions make them easy to set up, move around, and, in certain cases, operate in a handheld manner. They are also cost-effective, as TIJ models like the Anser U2  Pro-S are available for less than $1,500. Further, they require little-to-no professional maintenance due to their simple design and lack of printheads—TIJ cartridges contain printheads, the TIJ itself does not.

However, not all TIJ printers are perfect for every application. Many TIJ models, for example, are only compatible with one type of ink formula (e.g., water-based formulas or solvent-based formulas). This restricts their substrate compatibility as water-based formulas are well-suited for porous materials while solvent-based formulas are well-suited for non-porous materials. Although some TIJ models like the Anser Pro-S are compatible with both substrate classifications, it’s important to note that many are limited. 

In addition, TIJ printers are generally not capable of producing codes at industrial high speeds. While high-speed models do exist (e.g., the newly released Anser X1 has a max printing speed of 300 m/min), most TIJ printers are limited to around 120 m/min.

TIJ Printer Pros:

TIJ Printer Cons:
  • Compact, lightweight, and highly portable
     
  • Available at a low cost
     
  • Have minimal upkeep requirements
  • Most TIJ models are slower than CIJ printers (excluding newer TIJ models like the Anser X1)
     
  • Not all TIJ printers are compatible with both porous and non-porous substrate

 

High-Resolution Case Coders

 

High-resolution case coders are designed to place large, sharp images and codes on shipping cartons and other forms of secondary packaging. Case coders are able to produce these markings due to their:

  1. Piezoelectric printheads
  2. Compatibility with thick ink formulas

Whereas TIJ printers use heat to pressurize ink, high-resolution case coders utilize electrical charges and vibrations. Within each piezoelectric printhead is a crystal or ceramic element. When electricity is exposed to the element, it bends backward, changes shape, and moves an attached vibration plate. This movement oscillates liquid ink into individual droplets before launching them onto the substrate. 

High-resolution case coders like the Precision Series 72mm use these operating principles to mark porous materials like cardboard, paper, wood, and stone with machine-readable barcodes, brand logos, and text. With these features, many organizations are able to directly mark their shipping containers with essential information and reduce the need for physical labels. 

Although case coders are effective, they are more expensive, so it’s important to do a cost/benefit analysis before investing.

High-Resolution Case Coder Pros:

High-Resolution Case Coder Cons:
  • Capable of creating large logos and images on porous materials
     
  • Creates machine-scannable barcodes/data matrices as well as clear text
     
  • Reduces physical label needs
  • Expensive upfront cost

Valve Jet Printers

Also referred to as “mechanical inkjet printers”, valve jet printers were one of the first DOD printers available on the market. At the time, they were often called “case coding systems”. Since the industry’s nomenclature changed, piezoelectric case coding printers gained the popular title “high-resolution case coder.”

As suggested by their name, valve jet printers pressurize ink through the use of valves. Every valve jet printer is built with a series of valve-controlled jets that alternately open and close to pressurize ink and produce individual drops. Once a product makes contact with the system’s printhead, the printer releases the drops to create the desired image or code. 

Valve jet printers are renowned for their ability to create high-DPI graphics and large images. Contemporary valve jet printers like the HandJet EBS 260 are well-known for their ability to print on everything from concrete to lumber and seemingly everything in between. However, valve jet printers are also archaic in a few ways. 

The biggest issue with valve jet printers is the valve system itself. The valves within a valve jet printer are known to carry short lifespans, requiring the need for regular maintenance. This substantially increases the overall cost of ownership and poses a constant risk of downtime and printing mistakes. The use of air to pressurize ink is also less reliable than heat or piezoelectricity. 

For these reasons, both TIJ printers and high-resolution case coders have gradually become preferred over valve jet models in recent years.

Valve Jet Printer Pros:

Valve Jet Printer Cons:
  • Compatible with both porous and non-porous materials
     
  • Capable of creating large logos, images, barcodes, and text
  • Relatively high maintenance needs
     
  • Less reliable than TIJ or high-resolution case coder options

Ready for the Benefits of Drop-on-Demand Inkjet Printing? Contact Us Today

From handheld TIJ printers to high-resolution case coders, the drop-on-demand inkjet field is filled with diverse technologies that benefit a wide range of industries. Whether you need to place thousands of text codes on a line of glass beer bottles or create large, vibrant images on cardboard cartons, DOD printers can help you complete your unique packaging applications with speed and accuracy. 

At InkJet, Inc., we carry a number of DOD printers that can help your operation become more efficient. If you’re looking for a new printer model, or if you’re curious about which DOD technology will work best for your needs, contact us today to learn about our different options. 

For more information regarding drop-on-demand inkjet printing,  contact us online today or call 1(800) 280-3245. 

 

 

 

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