Thermochromic ink is a new type of ink with a wide range of uses. It is generally divided into two types: reversible color and non-reversible color. The color change temperature and composition are different, and there are many varieties. It can be widely used in many aspects such as temperature measurement, early disease diagnosis, decoration and anti-counterfeiting. With the continuous improvement of people's living standards, people's pursuit of wear, use, and beauty has become increasingly intense. The research and development of low-temperature reversible thermochromic materials as soon as possible can gradually meet the needs of beautification of life and technological development.

Thermochromic inks have the ability to decolorize at a heating temperature of over 50°C and restore their original colors when cooled. Thermochromic screen printing inks (which can also change from one color to another) belong to a low-temperature reversible thermochromic material. The color-changing substance is composed of three components such as a color-forming agent. Compared with the main reversible thermochromic substances used for a long time-metal iodides, complexes, double salts and liquid materials, it has obvious color change and a wide range of color temperature. It can present the advantages of transparency, reversible change in coverage, and low price. The key technology of the function of the color-changing material-microencapsulation technology, the color-changing substance is made into microcapsule particles, and then the ink is mixed. The color-changing ink prepared in this way, due to the close contact of the three components of the reversible color, can make the color change vivid, sensitive, and not affected by other reactive substances, and can improve its heat resistance, durability and washing resistance.

Microencapsulation technology is to use natural or synthetic polymers, through the phase separation method, the interface reaction method to package the required components into several parts of the color-changing material selected according to the set color-changing temperature. And according to factors such as film formation, chemical stability, water resistance and reactivity, the resin of the capsule wall of the microcapsule is selected.

The size of the colored particles directly affects the ink's network performance, fluidity, fastness, printed product appearance and thermal discoloration function. For this reason, the size of the microcapsule particles must be controlled. The average particle size of the microcapsule particles is 20~35pm, within this range it can meet the requirements of ink composition.

As the main resin of the ink, the binder plays an important role in bonding pigments, forming ink films, and providing printability. Therefore, the choice of binder is the main factor that determines the performance of the ink. In order to make water-based inks suitable for screen printing, it is better to choose emulsion resins, but it has disadvantages such as poor pigment dispersibility and poor fluidity, so it needs to be equipped with "quantitative water-soluble resin.

The prepared microcapsule particles have a certain degree of hydrophilicity, which can be used to prepare water-based inks to reduce environmental pollution. In order to meet the thermal discoloration function and screen printability requirements of the ink, suitable rheological additives can be added.

Water-based inks are easy to produce bubbles during the preparation and printing process, which affects the quality of printing, so a certain amount of defoaming agent is required. For the ink used in textiles, in order to improve its fastness to washing, a certain amount of penetrant and fixing agent must be added.

The reversible thermochromic screen printing ink has good printability, clear print patterns, uniform color, strong adhesion to the paper base and fabric, and obvious thermochromic effect, which can meet the requirements of decoration and anti-counterfeiting technology. The ink is water-based ink. No pollution, non-toxic, no peculiar smell, easy to use, safe and reliable. Combined with a variety of color non-thermochromic materials, it can improve the decoration and interest of the product, and has a larger development prospect and potential market.

Thermochromic ink (also called thermochromatic ink) is a type of dye that changes color when temperatures increase or decrease. Often used in the manufacture of many toys or product packaging, as well as thermometers. Thermochromic ink can also turn transparent when heat is applied; an example of this type of thermochromic ink is found on corners of an examination mark sheet. This proves that the sheet has not been edited or photocopied, and also on certain pizza boxes to show the temperature of the product.

Use on packaging can be to detect temperature history during shipping and to indicate proper heating in an oven

We supply thermochromic pigments more than 13 years, if you need it, please feel free to contact us!