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The smart fabric based on temperature-sensitive/light-sensitive dual-response is a functional fabric that can change color with temperature and emit green light in the dark after being excited by light. Prepared by silk-screen printing technology, it is made of temperature-responsive polymers, rare earth photosensitive paste, adhesives, thickeners, and other materials. When the temperature-responsive polymer is 10%, the rare earth photosensitive paste is 12%, and the adhesive is 25%, the printed cotton fabrics had the highest K/S value, the best abrasion resistance, and the best soaping color fastness. After 30 heating and cooling tests, the color depth and temperature-sensitive discoloration performance of the fabrics were still good. The fabric prepared by mixing orange and blue temperature-sensitive color change microcapsules and rare earth light response materials with different mass ratios can obtain continuous multi-color effect at 31–40 °C. Under the excitation of 365 nm wavelength, the fabric appears the characteristic green light of SrAl _2 O _4 : Eu ^2+ , Dy ^3+ luminescent materials. With the increase of temperature, the emission intensity increases first and then decreases. The luminance of the fabric after heating is obviously higher than that under the room temperature.

Visible signals are vital to human communication. Thermal signals are often difficult to observe unless they are in physical contact with the subject or an infrared thermal imaging system is used. In this study, we prepared a luminescent polyurethane composite (LPC), which can intelligently alter its colour and luminescence based on temperature. The LPC is fabricated from rare-earth luminescent materials (Sr _2 ZnSi _2 O _7 : Eu ^2+ , Dy ^3+ and Y _2 O _2 S: Eu ^3+ , Mg ^2+ , Ti ^4+ ), a heat-sensitive rose-red TF-R1 thermochromic pigment (TP), polyurethane (PU), and polyester fabric. Microstructure and crystal structure analyses were carried out to determine the basic material properties of the LPC. The reflectivity and K S ^−1 value under different temperatures indicate that blue and green light were absorbed by LPC at 25 °C and the absorption decreased at 45 °C. This results in the LPC turning white. The emission spectra demonstrate that the quinoid structure of TP blocked the light of Sr _2 ZnSi _2 O _7 : Eu ^2+ , Dy ^3+ . Meanwhile, the lactone structure of TP allowed the light emission of Sr _2 ZnSi _2 O _7 : Eu ^2+ , Dy ^3+ and Y _2 O _2 S: Eu ^3+ , Mg ^2+ , Ti ^4+ . As a result, LPC emits red light at low temperatures and blue light at high temperatures. The advantage of the fabricated LPC is that the output can be easily manipulated into patterns. The uncured PU could form various graphics to cooperate with visible signals. Therefore, the LPC has significant potential as a functional material in smart clothing, flexible electronics, and wearable devices.

In recent years, luminous coated fabrics based on SrAl _2 O _4 : Eu ^2+ , Dy ^3+ luminescent materials have attracted more attention. However, due to the single emission color of SrAl _2 O _4 : Eu ^2+ , Dy ^3+ luminescent materials, the application of prepared coated fabrics has certain liminations. Therefore, at present, there is a need to develop a kind of luminous coated fabric which has the capability of emitting multiple colors of light. In this work, fluorescent pigments and SrAl _2 O _4 : Eu ^2+ , Dy ^3+ luminescent materials were added to a coating slurry and uniformly coated over a woven fabric substrate. The effects of adding fluorescent pigments on the spectral characteristics of luminous coated fabrics were evaluated. The blue fluorescent pigment causes a significant blue shift in the emission spectrum of the blue light-emitting coated fabric, whereas the emission spectra of the orange and red light-emitting coated fabrics exhibit a significant red shift. The yellow-green fluorescent pigments significantly affect the coated fabric. The emission spectrum shows no evident change and is similar to the emission spectrum of white (without any fluorescent pigment) luminescent coated fabric. The afterglow brightness of the colored luminous coated fabrics decreases exponentially with time. Adding blue fluorescent pigments has a greater impact on the brightness of the coated fabrics. The initial brightness is lower and the afterglow brightness loss is higher when using yellow-green fluorescence. The pigment has little effect on the brightness loss of coated fabrics, and the initial brightness of the coated fabric increases when adding yellow-green fluorescent pigments. Fluorescent pigments result in relatively low color purity for each colored coated fabric. However, the color rendering index is high, and the color rendering performance for the light source is excellent.

Rare earth luminescent materials (RELMs) are commonly used in optics and products intended for safety and decoration. However, there is still a great challenge to alternate the emission performance after the RELMs are activated. In this work, a novel shutter luminous fibre (SLF) was developed using a water-spin method with polyacrylonitrile (PAN) as the filament material. The emission performance of the RELMs SLFs could be alternated at near-ambient temperatures. A heat-sensitive thermochromic pigment composed mainly of 7-Anilino-3-diethylamino-6-methyl fluoran (TF-BL1) served as the shutter material. The emitting properties, shielding effect, and the temperature response behaviour of RELMs SLFs with primary colour-emitting properties (Sr _2 ZnSi _2 O _7 : Eu ^2+ , Dy ^3+ ; SrAl _2 O _4 : Eu ^2+ , Dy ^3+ ; and Y _2 O _2 S: Eu ^3+ , Mg ^2+ , Ti ^4+ ) were investigated. The quinoid structure of TF-BL1 blocked the light of primary colours at low temperatures. At high temperatures, the lactone structure of TF-BL1 allowed the light of the RELMs to emit. SLFs with real-time responding behaviour have great potential as electronic skin in soft robotics, flexible electronics, and camouflage applications.

In this study, we intend to obtain a novel luminous fiber with colour-tuned luminescence via the photoelectron transfer of a phosphomolybdic acid pigment (PAP). The luminous fiber include the SrAl _2 O _4 : Eu ^2+ , Dy ^3+ materials as the luminescence sources, a solid solution of PAP and polyvinyl alcohol as the photoinitiator, amino silicone resin (ASR) as the surface-modified film-forming material and polypropylene (PP) as the matrix, which are prepared by the melt spinning method. The surface morphology was characterized using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, ultraviolet-visible (UV–vis) spectroscopy, photoluminescence emission spectroscopy, and CIE-1931 chromaticity coordinates. Thus, promising results were obtained, which denoted that the luminescence colour of the luminous fibers could transform from yellow–green to blue by adjusting the PAP concentration. The PL emission spectra of these luminous fibers consisted of two emission peak regions in the range of 430–530 nm. The intensity of the two emission peaks in the fiber reaches the maximum when the concentration of the PAP was 50%. Further, the fibers gradually turned blue with luminescence decay when the fiber was placed in a dark place. The existence of photosensitive discoloration was found to be directly related to the amino groups embedded in the silicone resin coated with the luminous surface material, which reacted with PAP to develop phosphorous molybdenum blue via the photo-reduction process. These findings provide valuable insights toward developing next-generation luminescent materials and multicolor luminous fibers.

The recycling luminous materials SrAl _2 O _4 :Eu ^2+ , Dy ^3+ is a kind of long afterglow phosphor, prepared based on the alcoholysis of luminous polyester fabric, which has excellent characteristics like high lightness and long afterglow time. However, for that the luminous materials SrAl _2 O _4 :Eu ^2+ , Dy ^3+ are recycling, and the process on the alcoholysis of luminous polyester fabric may affect its performance. Hence, in this study a couple of luminous materials SrAl _2 O _4 :Eu ^2+ , Dy ^3+ were recycled from luminous polyester fabric based on the method of alcoholysis, the phase structure and luminescent properties of the fibers were characterized by scanning electron microscopy (SEM), x-ray diffractometer (XRD), fluorescence spectrometer and afterglow luminance meter. The results deduced that under a certain condition, the luminous polyester fabric can be basically degraded, and the recovered luminescent materials can be obtained at a high purity. Our research supplies a strategy to recycle luminous phosphors as well as other functional materials, and hopefully it could inspire development for luminous materials and fibers.