Ultrasound-aided dyeing of cotton fabric with spirooxazines and photochromic properties

Abstract

Photochromic fabric can change color when exposed to a certain light wavelength. The fabric can reversibly restore to its original color after the light disappears. In this study, two spirooxazines with photochromic properties, i.e., N- ,4] oxazine] (Spirooxazine B), were synthesized. The spirooxazines were characterized by Fourier transform infrared (FTIR) and ultraviolet (UV) spectrophotometers. Spirooxazines A and B were used to dye cotton fabrics under ultrasonic irradiation. The results show that cotton fabric dyed with Spirooxazine B has excellent photochromic properties, and better fading time and fatigue resistance.

Preparation of waterborne polyurethane film based on spirooxazine containing hydrophilic groups

“…In particular, photo‐responsive polymers have gained great interest because light can be clean and free from time and space constraints 6–9 . Compared with others, spirooxazine has been extensively studied because of its good fatigue resistance, good thermal stability of the ring‐opening body, and less influence by the polarity of the solvent 10–12 . Recently, Rahimi used spirooxazine derivatives to functionalize dextran to prepare a dual photosensitive and pH‐responsive spirooxazine functionalized polymer 13 .…”

Screen-Printed Photochromic Textiles through New Inks Based on SiO2@naphthopyran Nanoparticles

“…All coated fabrics, especially those printed with SiO 2 NPs modified with silylated 3 H -NPTs, provided a remarkable compromise between coloration and bleaching kinetics, low residual color, good color contrast, photostability, and photodegradation resistance, proving to be excellent competitors over other photochromic textiles already reported on other works. ,− …”

“…The quest for innovative functional and smart textiles is one of the major goals of the textile and clothing industries, driven by the market and end-user requirements for fabrics with advanced features such as omniphobicity, antimicrobial activity, controlled release of oils and flavors, photo- and thermochromism, and fire retardancy, without compromising their comfort, easy care, and hygiene. , In 2014, the world market value for intelligent textiles was $795 million, and it is expected to reach $4.72 billion in 2020, with a compound annual growth rate (CAGR) of 34% from 2015 to 2020 . In particular, photochromic fabrics are a class of high-tech textiles with tremendous potential due to their ability to protect consumers from the harmful effects of UV exposure and their reversible UV-sensing properties; additionally, they impart trendy color changes to home decorations and fashion garments. ,− Naphthopyrans (NPTs), a class of organic photochromic dyes, are promising candidates for the production of photoresponsive materials, because they are easy to prepare, show efficient coloration/decoloration kinetics and good fatigue resistance, and are very versatile molecules, allowing an extensive selection of colors to be obtained. − Photochromic fibers and/or fabrics made from different substrates (e.g., cotton, polyester, − nylon, , acrylic, , wool, , and polyamide , ) have been produced by different dyeing procedures through the incorporation of photochromic organic molecules, mostly NPT- and spirooxazine-based compounds. The dyeing of fabrics with photochromic dyes by conventional processes encounters several problems associated with the dyeing procedure (e.g., dye degradation) and with the limited interaction between dye and substrate, such as (i) low dye uptake and reduced dye diffusion into the fibers, (ii) slow coloration/decoloration kinetics, (iii) total inhibition of photochromism, (iv) constraints imposed by the hardness of the matrix, and (v) low washing and light fastness characteristics. ,,, Some of these drawbacks can be overcome by, for instance, processing dyes into pigments using microencapsulation processes; although this methodology tends to increase the stability of the photochromic compounds, it usually confers a certain harshness and stiffness on the fabric, compromising the comfort of the user. , Alternatively, photoswitchable textiles have been produced by screen-printing using inks containing photochromic dyes, − …”

Inkjet printing and UV-LED curing of photochromic dyes for functional and smart textile applications

“…21 Meanwhile, photo-degradation of photochromic dyes is commonly observed under prolonged UV-irradiance. 34–36 …”