Thermal Printers – CompTIA A+ 220-1101 – 3.7

Thermal printers are popular output devices for retail receipts and other temporary prints. In this video, you’ll learn about thermal printers, feed assemblies, heating elements, and thermal paper.

A thermal printer operates by feeding a specially coated white paper into the printer. It heats certain parts of that page. And any part that’s heated turns black. This doesn’t use any ink. It uses no toner, instead simply uses heat to create the output. These are very quiet printers. We most commonly associate thermal printers with receipt printers. And if you think about the receipt printer that you would see checking out at a store, you know that they are very quiet when they operate.

One disadvantage of thermal printers, though, is that the paper is very sensitive to heat. And if you have that paper after printing and you leave it in the sun or it’s near a heat source, the entire page will turn black. There’s also a similar problem if you use a clear tape on thermal paper. You’ll notice that the section where the tape is covering will slowly turn white. This is why we usually say that if you’re planning to archive any information, you probably do not want to use a thermal printer.

To be able to pull the paper through the thermal printer, you need some type of feed assembly like this one. The feed assembly is a long cylinder that holds the paper in place with friction. There are gears on the side that turn the cylinder and feed the paper through the printer.

Here’s a better view of the feed assembly with the top of this thermal printer open. You can see that it is just a cylinder. There’s the gear on the right side that turns. And that pushes all of the paper through the printer.

To be able to create the output on a thermal printer, you need a heating element. And this silver component in this printer is the heating element that’s creating the information on this page. The heating element doesn’t move. The paper simply moves by the heating element. And different parts of the heating element will heat up to create the black color on the page.

Here’s a closer view of that silver heating element. It works extremely quickly and very effectively. And as this paper is sliding through, there’s practically no noise from the actual printing process. This color change occurs because of a chemical that’s been added to the paper. We sometimes refer to this as thermochromatic paper or thermal paper. And when you heat different parts of paper, it will change color.

If you’ve ever gotten a receipt from a cash register or credit card terminal, you’ll notice that the paper that it’s using is thermal paper. Although this looks like normal paper, it feels very different and obviously works very different than regular paper. So if you need to purchase or replace paper that’s in a thermal printer, make sure you’re using exactly the right kind of paper.