Direct thermal printing and thermal transfer printing, what is the difference?

Updated: 2021-05-15

Two main thermal printing methods

Thermal transfer printing and direct thermal printing are both methods of printing images on a variety of materials. However, there are some important differences between the two, and understanding those differences will help you determine which technology is best for your application.

One of the most important differences is that thermal transfer printers use a special thermal ribbon that contains pigment, while direct thermal printers use heat-sensitive paper.

Thermal transfer printers use an electric current to create prints through a thermal head. This process relies on the fact that electricity can heat up an electro-conductive ribbon.

Direct thermal printers

Direct thermal printing is the process of printing using the direct heat transfer process. The advantage of direct thermal printing is that it is faster and requires on ink.

This process prints an image formed by a chemical reaction between the image-bearing material and a special heat-sensitive paper. The heat generated by a special thermal print head causes the image on the paper to change color.

While inkjet and laser printers have become the norm for the home and office, their effectiveness in the industrial environment has been limited, due to the clog-prone print heads that are prone to failure.

Direct thermal printing, however, offers the same high-quality, color-printing capabilities as its competitors without the ink or toner.

The lack of moving parts, along with its durability and lower cost of ownership, make the direct thermal printing system ideal for industrial environments.

Direct thermal printing is used in a wide variety of applications, however, direct thermal printers cannot print on typical paper such as letterhead.

Thermal label printing

The most obvious example of direct thermal printing (in this case also called DT labeling) is with shipping labels.

Direct thermal vs thermal transfer label technology

The direct thermal labels themselves are easy to print. They are blank labels you can print on at home, and they are compatible with any thermal printer. The labels are great for shipping since they can be written on with a pen and are easy to remove when you’re done shipping.

Direct thermal printers are a great option for businesses that need to print only a small number of copies of their documents at a time. Unlike laser printers, which use toner cartridges to transfer ink to the page, direct thermal printers use a special kind of paper that is pre-coated with a dye.

When the paper passes over the heating elements, the dye turns black and the image is transferred to the paper. While this method is less expensive than laser printing, saves printing costs it also has some drawbacks.

Since the dye is heated and transferred directly to the paper, there is no reservoir for the ink, making it impossible to print on the reverse side of the page. The other popular heat printing method is thermal transfer printing.

Thermal transfer Method

The thermal transfer printing process uses both a heater and a pressure device (heat press) to transfer your image onto a media substrate. The process is far less expensive than other methods of printing, such as dye-sublimation, which is one of the reasons why thermal transfer printing is quickly gaining popularity.

A printhead and a thermal transfer resin ribbon is used to apply the thermal transfer medium to the substrate. The thermal transfer ribbons consist of a series of printed graphics that are lined up to create a linear image.

A printhead is made up of one or more nozzles that apply the thermal transfer medium, which is normally wax-based ink, to the substrate. The thermal transfer method usually requires images printed with higher DPI to achieve desired sharpness.

Heat transfer labeling, Rfid thermal label printers

RFID thermal label printers are a fast and efficient way to label your products. With RFID labels you can store information such as price, weight, quantity, and barcode on a product. This process is great for inventory identification when you have a large number of products to label and you don’t have the time to individually label each one.

The RFID thermal transfer labels are great for when you have a wide range of products that you want to keep track of stock and inventory. With the barcode labels and asset tagging, you can easily keep track of each product that comes in and out of your company.

Be aware that harsh environmental conditions mainly extreme temperatures may cause damage to the standard thermal paper which is not suitable for outdoor applications and may cause the barcode unreadable.

Thermal labels for outdoor applications

When you use labels for your company, you want to ensure that the labels are durable. Some labels are durable enough to adhere to boxes of product for shipping, while others may only be suitable as return address labels. Without durable labels, it is difficult to ensure that the labels are going to stick around long enough for your customers to see, which could lead to a lost sale.

Thermal labels for an outdoor application feature a special coating that withstands weathering and sunlight and is also resistant to chemicals. It was originally developed to label stocks such as food and medical supplies, but now it can be used in a variety of other situations. You can label your garden tools, plants, and other outdoor supplies using a direct thermal printer.

Do laser printers use direct thermal printing process?

The laser printer was the first commercially successful application of direct thermal printing, the technique of applying heat directly to a specially coated heat-sensitive label. With direct thermal printing, the thermal print head does not have to contact the substrate, so the label materials may not be suitable for pressure-sensitive adhesives.

What does Sato mean and why is Sato used in connection with heat transfer Technology?

SATO is a Japanese company, that was the first company in the printing industry to introduce the first handheld labelers in 1962 and the world’s first thermal transfer printer in 1974.  For decades, printing was done by mass production, moving a sheet of paper through a machine that added ink to a page. For the most part, this technology still exists today.

It was SATO who improved the print performance with the technique of direct thermal printing that promised to produce higher quality prints in less time. Since its initial release, the technology has continued to evolve and is now available in everything from laser printers to mobile phone chargers. 

Now Sato operates all over the world, e.g. SATO America produces Industrial Thermal Printers, Print Engines, Laser Printers, and RFID embedded tags and labels.