lämpöpaperin

Lämpöpaperi, also known as thermal paper, is a special type of paper that has been coated with a heat-sensitive dye and a developer. When exposed to heat, the dye and developer react, causing a color change and thus creating an image or text. This technology is commonly used in receipts, labels, tickets, and fax machines.

The heat-sensitive coating typically consists of three main components: a leuco dye, a developer, and a sensitizer. The leuco dye is a colorless or faintly colored organic compound that can change to a colored form. The developer, often an acidic substance, initiates the color change reaction when heated. The sensitizer helps to lower the melting point of the mixture, allowing the reaction to occur at lower temperatures, typically from a thermal print head.

When a thermal printer applies heat to specific areas of the lämpöpaperi, the coating melts. This allows the leuco dye and the developer to mix and react, resulting in a visible mark. The image formed is usually black, but other colors are also possible. The sharpness and durability of the print depend on the quality of the paper and the printing process.

Lämpöpaperi has advantages such as speed and simplicity of printing, as it does not require ink or toner. However, the printed information can fade over time, especially when exposed to heat, light, or certain chemicals. This makes it less suitable for long-term archival purposes compared to other printing methods. Recycling of lämpöpaperi can also be challenging due to its chemical coating.