Search

Caffeic acid (CA) was treated on the surface of polyester fabric (PET), and Fe2+ was used as an intermediate to form chelates with CA to increase the roughness of the polyester surface. With the addition of n-octadecyl mercaptan (SH), the mercapto group reacted with the carbon–carbon double bond of CA on the PET surface through enol click chemical reaction. Meanwhile, CA was polymerized under UV radiation, and thus CA-Fe-SH-PET was prepared. The introduction of SH with a long carbon chain reduced the surface energy of the PET, in order to endow the polyester fabric with a superhydrophobic/lipophilic function. Combined with XPS and FTIR tests, the new carbon–carbon double bond's binding energy and vibration peak were found on the fabric surface, indicating that CA was adsorbed on the PET fabric's surface. After adding SH, the double bond disappeared, demonstrating that SH and CA occurred a click chemical reaction and were grafted onto the PET fabric's surface. The water contact angle (WCA) of CA-Fe-SH-PET was about 156 ± 0.6°, and the scrolling angle (SA) was about 3.298°. The results showed that the modified polyester had a robust superhydrophobic stability in washing, mechanical friction, sun aging, seawater immersion, organic reagent, and acid-base erosion derived from the good adhesion of polymerized CA (PCA). At the same time, the modified polyester fabric had good self-cleaning, antifouling, and oil–water separation performance. It was found that the CA-Fe-SH-PET fabric had unique photothermal conversion characteristics, which can convert the absorbed ultraviolet light into thermal energy, providing a local warming effect due to rapid heating and improving the transmission speed of heavy oil (engine oil and diesel). The CA-Fe-SH-PET fabric can further prevent the transmission of ultraviolet rays, and the UV resistance of CA-Fe-SH-PET fabric is far higher than the UV resistance standard. The preparation method is simple, fast, efficient, and environmentally friendly, and it has better a potential application value in the oil–water separation field. [ABSTRACT FROM AUTHOR]

This paper is concerned with the quality of lines and disperse ink in printing patterns on different untreated polyester fabric constructions. The lines running in the weft and warp directions were printed on polyester fabric constructions, and printing accuracy was assessed. Ink spreading is one of the important factors that influences the ink distribution. Thus, in order to acquire satisfactory ink‐jet printing products, it is essential to control the spreading of ink on the polyester fabric. To meet these conditions, a series of chemicals (disperse dye 5.01 wt%, PVP‐K30 0‐2 wt%, DEG 5‐20 wt%, water 64.17‐79.17 wt%, etc) with different mass fractions was used to prepare disperse ink. The jetting behaviour of ink was related to its surface tension and viscosity, which was characterised by an automatic surface tensiometer and rotational viscometer. Line profile was used to evaluate the printing effect. Low field nuclear magnetic resonance and three‐dimensional super depth digital microscopy were used to reveal the relationships between the state of water, ink diffusion behaviour and printing sharpness. The results showed that increasing ink viscosity or decreasing free water content is advantageous to improve the sharpness of the printing pattern. The effects of fabric structural parameters on line image quality are discussed. The printing quality was closely related to the weight and structure of fabric. The heavy weight fabrics had accurate print pattern sharpness. The fastness test results showed that the ink printing pattern had good colour fastness. [ABSTRACT FROM AUTHOR]

A novel high-temperature disperse dye-based ink, designed for direct digital printing on fabrics, has been developed to eliminate the need for chemical pre-treatment. This innovative ink utilizes a temperature viscosity response mechanism and incorporates a new thermosensitive dye, enabling direct printing on polyester fabrics without pre-chemical treatment. The key to its temperature viscosity response properties is the addition of the nonionic surfactant L64 (poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) PEO-PPO-PEO). Extensive evaluations of its physicochemical properties, including viscosity, conductivity, pH, surface tension, particle size, and inkjet droplet formation, have confirmed the ink's superior sprayability and overall quality. Notably, when applied to polyester fabric, this ink enhances print clarity and pattern quality while ensuring robust color fastness to rubbing and washing, all without requiring fabric pre-treatment. Furthermore, a comparative analysis of the hand feel between fabrics printed with this ink and unprinted fabrics underscores the minimal impact of the printing process on the fabric's texture. This new type of thermosensitive ink application can effectively reduce the dependence of textile printing fabrics on chemical pretreatment, and effectively reduce the use of water resources in the printing process. • Triblock copolymer (PEO-PPO-PEO) is added to high temperature disperse dye ink. • This new type of thermosensitive ink is applied to polyester fabrics without the need for chemical pretreatment steps. • Thermal ink has good spraying performance. • The fabric printed with thermosensitive ink exhibits excellent printing accuracy and color fastness. [ABSTRACT FROM AUTHOR]

We report an improved printing ink of polyester fabric employed in the production process of inkjet printing. In the design of printing ink, the solubility parameters of reagent and HLB value of surfactant are used to prepare the ink. This production process does not require the pretreatment of polyester fabric to directly carry out inkjet printing. By regulating the intermolecular force relationship between the components of ink and the compactness of ink microstructure, it can improve the diffusion of ink on the surface of polyester fabric. The low-field NMR (LF-NMR) revealed the correlation between the fluidity and transverse relaxation time of main reagent solutions and ink. The test results show that there are three types of water: hydrogen-bond water, bound water and free water in main reagent solutions and ink. The LF-NMR was also used to investigate the relationship between ink viscosity and transverse relaxation time. It was observed that the transverse relaxation time (1084.4–410.3 m s, peak maximum time of T 22) of ink decreases with the increase of ink viscosity (2.3–11.1 mPa s). The viscosity and transverse relaxation time of ink is associated with the intermolecular force and the compactness of microstructure of ink. The formation of ink droplets was systematically observed by the ink droplet observation instrument. When the surface tension and viscosity of ink are 32.2–37.4 mN/m and 2.3–8.8 mPa s, respectively, the ink can be smoothly inkjet. With the increase of viscosity of the ink (2.3–8.8 mPa s), the sharpness of printing pattern is obviously improved, and the change rate of the line width (W) of the printing pattern is reduced from 52.6% to 4.4%. The microstructure of ink can bound the solvent of the ink, reduce the fluidity of the solvent, and improve the sharpness of the printing pattern. The test results of KES style and color fastness of the printed fabric show that the printed fabric fully meets the wearing requirements. Compared with other the soap liquid of printed fabric, the soap liquid of printed fabric RD-2B has strong UV absorption strength, the soap liquid RD-2B has a higher dye content. The characterization results of volatile organic compounds (VOC) in ink SDS R7 is 17.0 g/kg. The chemical oxygen demand (COD) values of printed fabrics RD-2B and SDS R7 are 150.0 and 102.0 mg/L, and the biochemical oxygen demand (BOD 5) values of printed fabrics RD-2B and SDS R7 are 130.0 and 97.7 mg/L. Compared with the common polyester fabric printing ink (ink RD-2B), the prepared ink has the characteristics of environmental protection, high production efficiency and low energy consumption, which has the potential to achieve green printing. [ABSTRACT FROM AUTHOR]