10th March 2023
The use of thermal paper began being popular in the 1960s, as an ink printing alternative that reduced the need for companies to purchase expensive inks. Unlike plain paper which needs ink to transfer information, thermal paper utilises chemicals and heat to create an image, but it is not quite as simple as that! In this blog post, we are going to uncover the science behind our thermal paper rolls, including how they work and how they have continued to develop and improve over the years.
As a company that specialises in the paper industry and thermal till rolls, we have over 40 years of experience and knowledge to provide all of our customers with top-quality information about the products we stock.
Thermal paper rolls have become essential to many businesses and commercial industries and are probably used in the majority of print machines around the world. They offer fast, efficient, and cost-effective printing solutions, which is why many companies opt for these paper rolls over plain types that require additional ink ribbons and cartridges. The science behind thermal paper rolls is based on a simple yet innovative technology that produces high-quality and smudge-free prints. Plus, as you no longer need to purchase cartridges and ink products, using thermal paper can overall be more environmentally friendly, which is great for companies striving towards greener goals.
The process of thermal printing begins with the creation of the paper roll, which is coated with a special thermal layer that contains heat-sensitive dyes. The dyes (leuco dyes) are formulated to react to heat in a specific way, resulting in the production of high-quality images. The thermal layer is usually protected by a wax-like coating that helps to prevent smudging and fading.
There are four common chemicals that are used in the production of thermal paper, that when combined create a clear and long-lasting image. These are:
Lueco dyes
Developers
Sensitizers
Stabilisers
As mentioned above, thermal paper is coated with a thin layer of leuco dye, which at first is colourless. However, when heat is applied above its melting point within an acidic environment, the dye then becomes coloured. To create an acidic environment, a developer is included within the coating too. The developer is an essential component to produce colour.
The two most popular developers that are used are Bisphenol A (BPA) and Bisphenol S (BPS), as well as sulfonylureas and zinc salts. When all of these substances mix together with a heat source, the dye becomes dark. To ensure the chemical reaction is controlled and successful, sensitizers also have to be included, which are usually 3-methyl-phenoxy or 2-(benzyloxy) naphthalene, that melt around 100°C. Sensitizers are substances which help to improve the thermal reaction of the coating, helping to mix the dyes and developers together in the melting process. The final step of the manufacturing process is adding a stabiliser which ensures a smudge-free and long-lasting print.
To print an image onto the roll requires a thermal printer. Thermal printers do not include ink cartridges and are mainly composed of a drum and print head. The print heads include minuscule semiconductor elements that transmit heat when the paper is fed through. As soon as the thermal paper and print head come in contact, the temperature will cause a chemical reaction that results in text or an image appearing.
Since the invention of thermal paper, there have been concerns about the way in which it can impact human health, specifically related to the use of BPA chemicals. BPA is used in the manufacturing of thermal rolls due to its heat resistance and stabilising properties, however, research has shown that it can pose health risks including allergic reactions, heart disease, infertility, and other serious conditions.
Although the use of BPA in paper rolls did not have a significant impact on health, there was an EU ban on the substance in January 2020 to reduce risks totally. Now all thermal rolls are BPA-free, including all of the products that we manufacture and stock on our website! Despite these rolls containing zero BPA chemicals, they still perform to the same standard and are compatible with all thermal printers, whether that be a cash register, EPOS system, credit card terminal, or ATM. You can now acquire thermal rolls that are durable, eco-friendly, and smudge-free, without any health risks!
Here at BPC UK, all of our products are designed and manufactured with the end user in mind; to deliver our customers the very best of the best. All of our rolls are created out of the finest, responsibly sourced European paper, to ensure you receive high-quality products. Please feel free to browse our extensive range of paper rolls on our website or if you require further information, contact us on 01772 622804 and we will be more than happy to help!
