How does a thermal printer work?

Thermal printers are crucial for many businesses.

However, are you aware of how thermal printers

are able to produce large quantities of durable

labels, signs, and barcodes?


In contrast to inkjet and dot matrix printers,

thermal printers produce images using a

heated printhead.

This method produces images with superior

print quality and increased durability. 


There are two types of thermal printers: thermal transfer

and direct thermal.

Each utilizes a thermal printer that provides heat

to the marking surface.



If you need to print out barcodes, particularly on labels,

tags, or wristbands with a lengthy shelf life or that are

exposed to sunshine, dampness, or severe

circumstances, you're probably utilizing

or considering employing thermal printers.


Thermal-based printing is also an excellent choice

if you're interested in:

  • Media flexibility

  • Low-maintenance, durable printers

  • Application modularity

Alternative technologies, such as impact printers,

are more susceptible to failure in industrial

and dynamic settings.

Frequently, they lack the print quality necessary to generate

clear, consistently scannable barcodes and are not designed

for adhesive label media

(Impact printers operate by striking an ink ribbon with a

metal or plastic head. Dot matrix, daisywheel, and

ball printers are examples).



Star Micronics printer in black

                                                                                                                                        Image credit:

There are two kinds of thermal printers that you can

choose from:


Thermal transfer printers utilize a heated printhead that melts ink

onto the media by applying heat to a ribbon.

The ink is absorbed, so incorporating the picture into the media.

This approach offers superior picture quality and longevity

compared to other on-demand printing technologies.

Paper, polyester, and polypropylene are some of the

media types that thermal transfer printers can

accept in addition to direct thermal printers.



Without requiring a ribbon, toner, or ink, direct thermal printers

produce images directly on the printed medium.

This approach utilizes chemically treated, heat-sensitive material

that turns black when passed beneath a thermal printer.

Consequently, this medium is more susceptible to light,

heat, and abrasion.

And, labels and tags are not as long lasting.

Images can deteriorate over time, and media

can darken when overexposed to heat, light,

or other agents.




Thermal Printers offer a wide range of applications in a

variety of industries:

  • Transport and Logistical Planning
  • Cross-docking and inventory
  • Picking and packaging
  • Receiving and shipping
  • Inventory administration
  • Evidence of delivery
  • Rental car return
  • Manufacturing
  • Construction in progress
  • Conformity labeling
  • Parts management
  • Equipment maintenance
  • Traceability
  • Quality control
  • Healthcare
  • Positive patient identification
  • Laboratory/pharmacy administration
  • Asset management
  • Accurate specimen labeling




photo of gray thermal printer

Print volume and speed

Comparing the two thermal printing techniques, direct thermal printing

is faster and requires less maintenance effort.

Simply replacing the label stock and maintaining the heat element

is sufficient for optimal production.

Image quality causes thermal transfer printing to be slightly

more precise and time-consuming.

It is also the user's responsibility to know which ink ribbon

works best with the specified print media.

This could be a deal-breaker for small firms with a high

turnover rate that demand a fast printer.


Small businesses that prioritize the speed and effectiveness

of their copies may favor direct thermal printers.

This printing technology is ideally suited for label stickers

and receipts that do not require a lengthy shelf life.

If, on the other hand, your firm relies largely on the quality

of labels such as barcodes and uses a variety of packaging

materials, thermal transfer printers should be

your first choice.


Printing method

Before commencing on your road of decision, you must first determine

the print method most frequently employed by enterprises

of all sizes.

What does it all mean, with so many options on the market

such as inkjet printing, direct thermal printing,

and thermal transfer printing?


A conventional inkjet printer operates by spraying or injecting

ink droplets from the ink cartridge onto the desired surface.

Since their invention in the 1950s, inkjet printers have changed

little throughout the years.

In contrast, thermal printers produced decades later

have seen substantial advancements, resulting

in two distinct thermal printing methods.


To achieve the desired result, direct thermal printing

employs a heating element in the printer to imprint

heat-activated label paper.


If you've ever received a receipt, it was likely printed

on a direct thermal printer.

As this approach does not require ink or printer ribbons,

the benefits of direct thermal printing are mostly monetary.

Label stock is the only component that requires

frequent maintenance.


As its name suggests, thermal transfer printing utilizes

heat to chemically adhere the ink to a label.

The term "label" is used because thermal transfer

printers are more versatile in that they can

employ a wide range of media types, including

sticker labels, cardboard packaging,

and even padded envelopes.

All of this comes at a price, as thermal transfer

printer ribbons must be replaced frequently.