There are temperature-sensitive chemicals on the paper, which will turn black after high temperature. When the pen tips cross, the friction instantly produces high temperature, which makes the place where the pen marks pass black.
The production principle of thermal paper is to coat the ordinary paper base with granular powder, which is composed of colorless dye phenol or other acidic substances, and the middle is separated by a film. Under the heating condition, the film melts and the powder is mixed to produce a color reaction. The color handwriting on thermal paper is unstable and easy to fade, which makes it difficult to identify the contents of the document. Thermal paper,
There are temperature-sensitive chemicals on the paper, which will turn black after high temperature.
When the pen tips cross, the friction instantly produces high temperature, which makes the notes black.
If you bake directly with a lighter, you will find that the paper changes color instantly.
It's best to use it as a file.
Coupled carbonless copy paper
It is formed by contacting two coated papers with each other, and its main components are base paper, chromonic coating and chromonic coating. Its working principle is that under the action of pressure, the chromonic coating reacts with the chromonic coating to synthesize colored substances on paper, and special friction paper is used for coloring. After it is torn off from the dry strip, it is pasted on the vin code of the frame, and the surface is leveled with bamboo board or plastic cloth. Scraping back and forth on rubbing paper can display numbers, and then this paper is called rubbing paper. The full name is motor vehicle rubbing paper. Its paper contains lead. This kind of paper is searched on Taobao. You will have everything. Authentic "Qianwanjia" special friction paper for motor vehicles is a national patent product. It is made of pressure-sensitive self-developing carbon and lead, self-adhesive and UV re-inspection technology, anti-counterfeiting technology and other advanced materials. It is mainly used for rubbing and archiving the engine number and frame number of vehicles during annual inspection, registration and transfer. The product has the advantages of environmental protection, anti-counterfeiting, strong adhesion, high definition of rubbing handwriting, quick and convenient use and long storage period. Qianchele rubbing paper is made of anti-tear material and UV cold composite technology. The national patent number is ZL200920 148302.8 Qianchele rubbing paper.