It turns out that the mug will change color than ordinary cups more than a layer of heat-sensitive materials made of temperature-sensitive coating. Thermosensitive materials, also known as thermochromic materials, its color will change from colored to colorless, or from colorless to colored, but also from a color to another color. A common thermochromic material is composed of an electron donor (colorant), an electron acceptor (color developer), and a solvent. The color developer accepts the electrons provided by the colorant and produces a color reaction, while the solvent determines the color change temperature of the material. Chromogenic agents include triarylmethane phenols and fluorescent alkane compounds, etc., color developers are mainly phenolic hydroxyl compounds and their derivatives, and solvents are mostly alcohols (such as n-hexadecanol). At elevated temperatures, electrons in atoms are transferred, leading to changes in the molecular structure of the organics, which results in a change in color. This reaction is reversible, and when it returns to its original temperature, the structure of the material's molecules also returns to its original state, and its color returns to its original color.
The color-changing mug is easy to make. The thermochromic materials ground into 3 to 10 microns of powder, mixed into water-based paint, first coated in ordinary ceramic mugs, and then put in the oven, baked at about 320 ℃, remove moisture and adhesives, so that thermochromic materials cured in ceramic mugs. Then the picture or photo to be "printed" on the mug is entered into a computer, and then hit with a special "printer" on a piece of thermal transfer paper. Thermal transfer can be printed on a variety of materials, the specific production method is the pattern with special transfer ink printed on the transfer of special paper, and then attached to the cup on the outside surface of the thermochromic coating, placed in the oven, at a temperature of about 220 ℃ for heat transfer processing. After a few minutes, the picture or photo on the transfer paper is printed on the mug, and a special color-changing mug is made. When the mug is added to hot water, the thermochromic coating becomes colorless and transparent, and the beautiful picture becomes visible.
Temperature-sensitive materials were first extracted from plants, and in order to obtain a greater variety of colors and higher yields, scientists have synthesized a large number of temperature-sensitive materials. Different temperature-sensitive materials have different ranges of sensitivity to temperature, so the color-changing cups made of different materials vary in color with temperature.
