The Importance of the Right Printhead

The printhead is one of the most critical components in any printing job, directly influencing print quality, efficiency, and overall results. Here’s what you need to know about the different printhead and how to select the most appropriate one for your specific printing project.

What is a Printhead?

Printheads are a component in all types of digital printers that are used to transfer the desired image onto your chosen print media. The printhead will spray, write, or drop the ink onto your paper in the pattern needed to produce the finished image.

Key functions of a printhead include:

• Housing multiple electrical components and nozzles.
• Holding different ink colors, most commonly cyan, yellow, magenta, and black.
• Sometimes including additional colors such as light magenta and light cyan.
• Receiving instructions from the printer’s electrical circuits.
• Controlling when and how much ink each nozzle releases.

In most inkjet printers, the printhead is located inside the ink or printer cartridge. When an image is sent to the printer, the printhead will receive the image information as instructions after which it will evaluate the necessary intensity, amount, and location where the ink will be required. Once the calculations are complete, the head will move horizontally going line by line until it has finished the image.

Types of Printheads: Key Differences

There are two primary types of printheads that will be used in the digital printing process, piezoelectric and thermal. Both use drop technology, but they create images in different ways and are best suited to different ink types.

Piezoelectric

The printheads use microscopic piezoelectric elements behind each nozzle. When an electrical charge is applied, the element flexes and releases a precise amount of ink onto the substrate. This gives printers excellent control over droplet size and placement, making piezoelectric printheads ideal for UV-cured, aqueous, and solvent-based inks.

Thermal

This alternative works by using heat instead of direct electrical movement. Tiny resistors behind the nozzles heat the ink until it vaporizes into bubbles, which force the ink onto the paper or substrate. The printhead then cools and refills before repeating the process. Thermal printheads are best for water-based inks, including latex inks used in outdoor signage and some textile applications.

How to Select the Right Printhead

Choosing the proper printhead is necessary not only when using inks are required for a run, but also because some printheads are better for printing specific designs, too. During printing, the individual drops of ink that are put onto the substrate will affect the overall quality of the image.

• Smaller drops will produce better definition and higher resolution. This is best when creating easy-to-read text, especially text that may have fine lines.
• Larger drops, are better when you need to print quickly by covering a large area. Large-format signage would be a great candidate for printing via large drops.

If your print piece requires high resolution and has small or fine details, using a piezoelectric printhead that has better control of the size of the droplets will provide you with the best quality image. For print pieces that might be larger but less detailed, thermal technology can make producing them less costly and often provide you with a piece that is suitable for your needs.

The ink you use and the quality and detail that your final piece requires will be the two vital components that determine which type of printhead will work best for your printing project.

Want more information about UV inkjet printers? Check out our Ultimate Guide to UV Inkjet Printers