What is Thermal Paper?

In our daily lives, we often come into contact with various types of paper, which carry words, images and information and form the basis of our communication, learning and work. Among many papers, thermal paper stands out for its unique characteristics and wide range of applications. In this paper, we will explore the definition of thermal paper, characteristics, manufacturing process, application areas and environmental considerations, in order to provide readers with a comprehensive and in-depth understanding.

1. The definition of thermal paper

Thermal paper, as the name suggests, is a temperature-sensitive paper. It is different from ordinary writing or printing paper, its surface is coated with a special layer of thermal coating. When this coating encounters a certain temperature, it undergoes a chemical reaction that changes the colour to form text or images. This feature makes the thermal paper in the case of no ink or ribbon, you can achieve the print function, greatly simplifying the printing process.

2. The characteristics of thermal paper

Temperature sensitivity: the core characteristic of thermal paper is its temperature sensitivity. When the thermal coating on the paper's surface reaches a certain temperature, a colour change will occur, usually from colourless to black or other colours. This change is irreversible, i.e. once formed, it cannot be restored to its original state.

No Ink Required: Unlike traditional printing methods, thermal paper printing requires no ink or ribbon. This not only simplifies the printing process but also reduces the cost of use as users do not have to buy and replace ink or ribbons.

Faster printing speeds: Since no ink is required, thermal printers typically print faster than traditional printers. This gives thermal paper a significant advantage in situations where a large amount of information needs to be printed quickly (e.g. supermarket checkout, logistics labelling, etc.).

Easy to fade: Another notable characteristic of thermal paper is that its printed content is prone to fading. Exposed to sunlight, heat or humidity for a long time, the printed content may gradually blur or even disappear completely. Therefore, thermal paper is usually used for short-term or one-time use occasions.

3. The manufacturing process of thermal paper

The manufacturing process of thermal paper is relatively complex, involving multiple steps and fine chemical processing. The following is its main manufacturing process:

1) Raw paper selection:

select high-quality paper as the substrate to ensure the flatness of the paper, strength and printing results.

2) Coating preparation:

Preparation of a special thermal coating, which is a key part of thermal paper. The coating contains temperature-sensitive chemicals such as colourless dyes and precursor compounds.

3) Coating application:

The prepared thermal coating is evenly applied to the base paper. This step requires precise control of the thickness and uniformity of the coating to ensure consistent print results.

4) Drying and curing:

After coating, the paper needs to be dried and cured to allow the coating to adhere firmly to the paper and achieve optimal print results.

5) Inspection and Packaging:

Finally, the manufactured thermal paper is inspected for quality to ensure that each batch meets the required standards. The paper is then cut, packaged and stored for subsequent use.

4. The application areas of thermal paper

Due to its unique characteristics and advantages, thermal paper has a wide range of applications in many fields:

Retail and supermarkets: In retail and supermarket environments, thermal paper roll is widely used in cash registers to print receipts and labels. Its fast printing and ink-free nature make the cash register process more efficient and convenient.

Logistics and courier: In the logistics and courier industry, thermal paper is used to print waybills, labels and barcodes. These printouts often contain important logistical information such as the origin, destination, weight and volume of the shipment.

Medical and Laboratory: In medical and laboratory environments, thermal paper is used to print test reports, prescriptions and patient information. Its fast printing and easy-to-fade characteristics make medical records more secure and convenient.

Fax Machines: Early fax machines also made extensive use of thermal paper to receive and print faxed content. Although modern fax machines have gradually used other types of paper, thermal paper in the fax field still has a certain market share.

5. Environmental considerations

Although thermal paper in several areas has a wide range of applications, its environmental protection has also triggered a certain amount of concern. As thermal paper may generate environmental pollution during its manufacture and use, it is vital to adopt environmental protection measures.

Recycling and reuse: Recycling and reuse of waste thermal paper is encouraged to reduce the burden on the environment. Recovered thermal paper can be used to manufacture recycled paper or other paper products.

Biodegradable: Develop biodegradable thermal paper to reduce its decomposition time in the natural environment. This type of paper is able to break down more quickly after disposal, reducing the long-term impact on the environment.

Reduce the use of chemicals: Minimise the use of harmful chemicals in the manufacturing process of thermal paper to reduce its potential harm to the environment and the human body.

6. Common thermal paper sizes

1) 3 1/8" (80mm) Thermal Paper

A popular size for point-of-sale (POS) systems, retail receipts, and ticket printing. Ideal for small to medium-sized businesses, food trucks, and handheld devices. Standard roll length: 50–100 meters (varies by supplier).

2) 2 1/4" (57mm) Thermal Paper

Commonly used for portable printers, credit card terminals, and slim receipt printers. Suitable for compact spaces or lightweight applications.

3) 4" (110mm) Thermal Paper

Often used for shipping labels, invoices, or medical records requiring larger print areas. Fits label printers and industrial-grade devices.

4) 8" (216mm) Thermal Paper

Designed for wide-format applications like logistics labels or medical imaging.

7. How to choose thermal paper

1) Determine the Application

3 1/8" thermal paper is perfect for retail receipts, while 4"–8" sizes suit labels or documents needing more space.

For food-related uses (e.g., restaurant receipts), opt for BPA-free thermal paper to comply with safety standards.

2) Check Printer Compatibility

Verify your thermal printer’s specifications (width, core diameter, and roll length).

Most receipt printers accept 3 1/8" thermal paper, but industrial printers may require wider rolls.

3) Consider Print Quality and Durability

High-resolution printers need thermal paper with a smooth coating for sharp text and barcodes.

For long-term records, choose top-coated paper to resist fading, heat, and moisture.

4) Evaluate Environmental Factors

Outdoor or high-heat environments demand UV-resistant or durable thermal paper.

For eco-conscious businesses, select recyclable or phenol-free options.

5) Balance Cost and Usage Frequency

High-traffic businesses (e.g., supermarkets) should prioritize bulk purchases of 3 1/8" rolls to reduce downtime.

Low-volume users can opt for smaller rolls to minimize waste.

In summary, thermal paper plays an important role as a unique recording medium in several fields. Its temperature sensitivity, no need for ink, fast printing speed and easy fading make it a significant advantage in specific situations. However, we also need to focus on its environmental friendliness and take measures to minimize its impact on the environment. Through continuous innovation and R&D, we can expect to see more environmentally friendly, efficient and versatile thermal paper products in the future.