Intelligent Chromic(color changing) textiles refer to the textiles that can display different colors with the changes of external environment conditions (such as light, temperature, pressure, etc.). It is an intelligent product with high added value and high efficiency, and has a good development prospect in the fields of textile, military, entertainment, anti-counterfeiting, etc.

For example, it can be used to make fashionable color changing clothes and decorative fabrics for civil use, for military camouflage, and for anti-counterfeiting materials in the field of anti-counterfeiting, which are widely used in bills, certificates and trademarks.

At present, the research and development technology of intelligent color changing materials is mainly divided into two categories.

One is the direct research and development of color changing fibers, such as post-processing technology, grafting polymerization technology, etc., to design color changing fibers with different functions; Another approach is to combine color changing dyes with fibers, such as microcapsule technology. At present, both China and some developed countries abroad have achieved research and development of the above two technologies, but there is still a significant gap in technological level compared to developed countries. In terms of product manufacturing technology level, most domestic enterprises are in the early stage.

Radiate Smart color changing sportswear

In recent years, many enterprises and research institutions in China have developed intelligent color changing fiber, and the overall level closely follows the international advanced level. For example, Xinxiang Chemical Fiber Co., Ltd. has developed "Egret" photochromic regenerated cellulose fiber, which can change colors in different light, and can be used in shirt, T-shirt, plaid fabric and embroidery fabric, as well as anti-counterfeiting logo, curtain, military outdoor special protective covert material and other fields;

By implanting self-developed "soft screen" products into the inner layer of clothing, the clothing can automatically change color, and present a variety of lighting patterns, so as to meet today's young people's pursuit of fashion textiles.

Reactive thermochromic microcapsule textiles

Thermochromic materials can not be directly applied to dyed textiles because of their high environmental sensitivity and low reactivity to fabrics. At present, the method to obtain thermochromic textiles is to coat the encapsulated thermochromic materials on the surface of fabrics through adhesives. However, the commonly used microcapsules with organic compounds as wall materials have poor transparency and stability, and the auxiliary use of adhesives will also affect the heating of dyes, resulting in the problems of low temperature change effect, slow response speed and temperature change color delay.

Many researchers also manufacture thermochromic textiles by embedding or stitching thermochromic elastic materials and thermochromic fibers into textiles and clothing to obtain stretchable and soft thermochromic wearable devices. However, in addition to color purity, comfort and durability, these thermochromic textiles have obvious and inevitable defects in compatibility with clothing. How to obtain reactive thermochromic microcapsule dyes for textiles is a hot issue in obtaining thermochromic responsive textiles.

Zhang Wan, Ph.D. of intelligent textile research group, School of textile and garment, Jiangnan University, prepared epoxy modified thermochromic capsules by hydrolysis polycondensation with 3-glycidoxypropyltrimethoxysilane as raw material, and then prepared reversible thermochromic cotton fabrics by ring opening covalent crosslinking of epoxy group.

Epoxy modified thermochromic capsules were prepared by hydrolysis polycondensation with 3-glycidoxypropyltrimethoxysilane as raw material, and then reversible thermochromic cotton fabrics were prepared by ring opening covalent crosslinking of epoxy group. The prepared epoxy modified thermochromic capsule has good thermal stability (above 300 ℃), and its discoloration temperature is 53 ℃. The color of modified capsule changes reversibly between blue and white with the change of external environment temperature.