What is the working principle of colored thermosensitive synthetic paper?

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The working principle of colored thermosensitive synthetic paper is mainly based on the chemical reaction of thermosensitive coating. The following is a detailed explanation of its working principle:

1、 Material composition

Color thermosensitive synthetic paper is usually made of BOPP (biaxially oriented polypropylene) film as the substrate, with a thermosensitive coloring layer coated on the surface. This chromogenic layer contains chemical substances such as leuco dyes (also known as colorless dyes) and colorants. Hidden dyes are colorless at room temperature and do not spontaneously develop color. Instead, they serve as a key component in thermosensitive reactions. The chromogenic agent plays a catalytic role in the thermosensitive reaction and participates in the chromogenic reaction together with the latent dye.

2、 Working principle

Heat reaction: When colored thermosensitive synthetic paper encounters a heated print head or other heat source, the temperature in the local area of the coating rapidly increases. High temperature causes the melting and chemical reaction of latent dyes and color developing agents.

Color development process: Under the catalytic action of the color developer, the structure of the latent dye changes, resulting in the appearance of color. This process is very fast and suitable for situations that require quick printing and marking.

Color fixation: As the temperature decreases, the color reaction is completed, and the color is fixed on the paper to form the desired image or text. Due to the special formula and processing of the thermal sensitive coating, the color produced by the color reaction is bright and long-lasting.

3、 Application and precautions

Color thermal sensitive synthetic paper is favored by the market due to its excellent performance and wide application fields. It is commonly used for instant printing of receipts, labels, receipts, restaurant orders, and packaging and decorative materials that require bright and fast printing. However, due to the reversible color reaction of thermosensitive materials, colored thermosensitive synthetic paper should avoid prolonged exposure to sunlight or high temperature environments during storage to prevent fading.

In summary, the working principle of colored thermosensitive synthetic paper is based on the chemical reaction between the latent dye and the color developer in the thermosensitive coating at high temperatures. This type of paper has the characteristics of fast color development and bright colors, and is widely used in various instant printing and packaging decoration fields.