Reversible humidity-sensitive color-changing fabric as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of functional textiles, and discloses a reversible humidity-sensitive color-changing fabric as well as a preparation method and application thereof. The preparation method comprises the following steps: S1, dissolving a compound K6Na17 [H3 {Co (H2O) 3} 2 (P4Nb9O40) 2]. 24H2O in a small amount of water, adding an adhesive and a printing paste, then adding a proper amount of water, and continuously stirring until the mixture is sticky to obtain slurry; and S2, printing the slurry on a cleaned and dried cotton fabric by using a magnetic bar printing machine, and pre-drying and baking to obtain the humidity-sensitive color-changing fabric. The reversible humidity-sensitive color-changing fabric is purplish red in an air environment, turns blue in a water-free environment at 50-70 DEG C, immediately turns purplish red in contact with water in air, and still has good fatigue resistance after five times of color-changing and color-fading experiments are repeated, so that a foundation is laid for future development of functional fabrics, for example, the reversible humidity-sensitive color-changing fabric can be applied to a humidity sensor and the like.

Description

Technical Field

[0001] This invention belongs to the field of functional textile technology, and relates to a reversible moisture-sensitive color-changing fabric, its preparation method and application. Background Technology

[0002] Fabrics are sheet-like objects woven from textile fibers, mainly used in clothing, decoration, and industry, and are an indispensable material in daily life. With the continuous development of the textile industry, fabric production has also shifted from traditional to functional. For example, color-changing behavior can be achieved by treating fabric fibers. Moisture-sensitive color change refers to the change in light absorption or emission properties of materials when stimulated by water vapor. In contrast, the external stimulation required for moisture-sensitive color change is relatively mild. The dehydration process can be achieved by heating, contact with desiccants, or vacuum drying, while the water absorption process involves contacting the material with liquid water or water vapor. Based on this characteristic, moisture-sensitive color-changing materials can be widely used in visual monitoring, carbon paper, humidity sensors, human sweat pore mapping, and the paint and coating industry. Patent (CN202210489345) discloses a dicarboxylic acid Ni(II) water-induced color-changing coordination polymer with a 2D→3D polylocking structure and its preparation method; however, the color-changing temperature range of this complex is 150-267℃, and the color-changing point temperature is relatively high, limiting its application range in daily life. Patent (CN202311589049) discloses a water-induced reversible color-changing PVC material, using benzotriazole or benzotriazole compounds as the water-induced color-changing agent. Patent (CN202510786653) discloses a method for preparing a cellulose-based water-induced deformable and color-changing film. In this patent, the color change occurs when the film absorbs water and swells, causing light scattering and changing the surface color from red to light red. Based on currently published patents, research on moisture-sensitive color-changing fabrics is limited, and most of the disclosed patents involve immersion in water, primarily using water-induced color change, and exhibit low sensitivity to moisture.

[0003] Therefore, it is necessary to develop a color-changing fabric that is sensitive to moisture. Summary of the Invention

[0004] In view of this, the present invention provides a reversible moisture-sensitive color-changing fabric, its preparation method and application, which turns purple-red immediately upon contact with water in the air and has excellent fatigue resistance.

[0005] This invention provides a method for preparing reversible moisture-sensitive color-changing fabric, characterized by comprising the following steps:

[0006] S1. Dissolve the moisture-sensitive compound in water, add the adhesive and printing paste, then add more water and stir continuously until a viscous consistency is reached to obtain a slurry; the molecular formula of the moisture-sensitive compound is K6Na. 17[H3{Co(H2O)3}2(P4Nb9O 40 )2]·24H2O;

[0007] S2. The slurry is printed onto a cotton fabric that has been washed and dried, and then pre-dried and baked to obtain a reversible moisture-sensitive color-changing fabric loaded with a moisture-sensitive compound.

[0008] K6Na 17 [H3{Co(H2O)3}2(P4Nb9O 40 [2]·24H2O is a cobalt-niobium-oxygen cluster compound. The cobalt ion has a six-coordinate configuration, with the coordinating atoms coming from three oxygen atoms in the niobium-oxygen cluster and three water molecules. Based on coordination theory, the color exhibited by the cobalt ion is related to the number of water molecules and the coordination configuration of the cobalt ion itself; moreover, the bond energy of the coordinate bonds is relatively small, and under appropriate conditions, bond dissociation and recombination will occur, resulting in different colors due to different numbers of water molecules.

[0009] Furthermore, the adhesive is an acrylic polyurethane copolymer adhesive. Adhesive 939 is preferred.

[0010] Furthermore, the printing paste is a sodium alginate aqueous solution with a concentration of 5 wt%.

[0011] Furthermore, in step S1, the amounts of the compound, adhesive, and printing paste are as follows: each 10g of paste contains 0.2~0.8g of the compound, 0.05~0.1g of the adhesive, and 5~8g of the printing paste.

[0012] Furthermore, in step S2, the cleaning and drying process refers to soaking the cotton fabric in an ethanol solution for cleaning, then washing it with water, and finally taking it out and drying it.

[0013] Furthermore, in step S2, the pre-baking temperature is 70~80 ℃ and the time is 1~10 min.

[0014] Furthermore, in step S2, the baking temperature is 90~120 ℃ and the baking time is 1~10 min.

[0015] The present invention also provides a reversible moisture-sensitive color-changing fabric prepared by the above preparation method.

[0016] Furthermore, when the moisture-sensitive compound loaded on the reversible moisture-sensitive color-changing fabric is in a hydrated state, the reversible moisture-sensitive color-changing fabric appears purplish-red; when the moisture-sensitive compound loaded on the reversible moisture-sensitive color-changing fabric is in a dehydrated state, the reversible moisture-sensitive color-changing fabric appears blue.

[0017] Furthermore, the reversible moisture-sensitive color-changing fabric is purplish-red in the air and turns blue in an anhydrous environment at 50-70℃, and can maintain this color for more than a year.

[0018] The present invention also provides an application of the above-mentioned reversible moisture-sensitive color-changing fabric in a humidity sensor.

[0019] Compared with existing technologies, the fabric prepared by the method of this invention is purplish-red in an air environment containing water vapor, turns blue when heated under anhydrous conditions, and immediately turns back to purplish-red upon contact with air. The temperature change range is widely applicable in daily life. The entire color change is repeated 5 times and still shows good color change performance, indicating that the fabric has good fatigue resistance. The method for preparing color-changing fabric is simple, and the main substance of the color-changing agent is inorganic functional particles, which are less toxic than the substances used in the preparation process of organic molecules. The preparation process is simple and lays the foundation for the development of functional fabrics in the future. Attached Figure Description

[0020] Figure 1 The compound is K6Na 17 [H3{Co(H2O)3}2(P4Nb9O 40 Infrared spectrum of 24H2O;

[0021] Figure 2 The compound is K6Na 17 [H3{Co(H2O)3}2(P4Nb9O 40 )2]·24H2O color change behavior before and after different dehydration;

[0022] Figure 3 This is a schematic diagram illustrating the color change behavior of the fabric in Example 2 at different temperatures;

[0023] Figure 4 This is a schematic diagram of the color change behavior of the fabric in Example 3 under different temperature conditions. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to specific embodiments.

[0025] It should also be noted that, in order to avoid obscuring the present invention with unnecessary details, only the structures and / or processing steps closely related to the solution of the present invention are shown in the specific embodiments, while other details that are not closely related to the present invention are omitted.

[0026] Additionally, it should be noted that the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0027] In this invention, adhesive 939 is a commercially available product, belonging to acrylic polyurethane copolymer adhesive, purchased from Beijing Jieershuang High Technology Co., Ltd.

[0028] Example 1

[0029] Compound K6Na was prepared according to the preparation method described in the article Inorg. Chem. Commun., 2020, 111, 107612. 17 [H3{Co(H2O)3}2(P4Nb9O 40 The structure was confirmed by infrared spectroscopy and X-ray single crystal diffraction. The sample was collected, ground, and prepared for later use.

[0030] The infrared spectrum of the compound prepared in Example 1 is shown below. Figure 1 As shown.

[0031] The compound prepared in Example 1 was analyzed in single crystal form at 296 K using a Bruker APEX-II CCD single-crystal diffractometer, and all diffraction data were collected. The radiation source was Mo Kα rays from a graphite monochromator (λ = 0.71073 Å). The coordinates of hydrogen atoms on the water molecule were obtained using the difference Fourier synthesis method, while the coordinates of all non-hydrogen atoms were obtained directly and optimized using anisotropic thermal parameter correction and matrix least squares method. Hydrogen atoms were directly added to the molecular formula. Crystallographic data and structural parameters are shown in Table 1.

[0032] Table 1

[0033] Space Group Unit cell parameters (a / Å) Unit cell parameters (b / Å) Unit cell parameters (c / Å) Unit cell parameters (γ / °) <![CDATA[Unit cell parameters (V / Å 3 )]]> sample Cmmm 12.30(5) 12.10(5) 55.55(2) 120 7145(11)

[0034] To investigate the humidity-responsive color-changing properties of this compound, this experiment dehydrated the crystals by heating, aiming to explore the response law and reversibility of its color to humidity changes. The experimental procedure is as follows:

[0035] The purplish-red crystals K6Na 17 [H3{Co(H2O)3}2(P4Nb9O 40 [2]·24H2O was placed in a small glass bottle, evacuated, and sealed. It was then placed on a flat heating plate and heated under controlled temperature. It was found that when the temperature was heated to 50 ℃, the crystals changed from purplish-red to blue. After the bottle cap was opened, the crystals immediately returned to purplish-red.

[0036] Color changes are as follows: Figure 1 As shown in the figures, Figure a represents the crystal's natural purplish-red color, Figure b represents the color after vacuuming and heating to 50 °C, which appears blue, and Figure c represents the color after the crystal is exposed to air and returns to its purplish-red state. These experimental results demonstrate that the obtained crystal exhibits excellent water-responsive color-changing properties; its color change is sensitive and reversible, providing experimental evidence for the subsequent development of sensing materials or intelligent color-changing systems based on water molecule recognition.

[0037] Example 2

[0038] Step 1: Soak the cotton fabric in an ethanol solution, then wash it with water, dry it, and set it aside.

[0039] Step 2: Weigh 0.5 g of the K6Na prepared in Example 1. 17 [H3{Co(H2O)3}2(P4Nb9O 40 )2]·24H2O is dissolved in 3 mL of water, 0.1 g of binder 939 and 5 g of 5wt% sodium alginate are added, and an appropriate amount of water is added to make up to a total mass of 10 g of slurry. Stir continuously until it becomes viscous.

[0040] Step 3: Print the slurry prepared in step 2 onto the fabric obtained in step 1 using a magnetic rod printing machine. Pre-dry at 80 ℃ for 3 min, then bake at 90 ℃ for 3 min to obtain a reversible moisture-sensitive color-changing fabric in pink.

[0041] To investigate the humidity-responsive color-changing properties of this fabric, this experiment dehydrated the crystals loaded on the fabric by heating, aiming to explore the response law and reversibility of its color to humidity changes. Figure 3 The color change of the fabric obtained in Example 2 during the experiment is shown.

[0042] The specific experimental procedure is as follows:

[0043] The pink reversible moisture-sensitive color-changing fabric obtained in Example 2 was placed in a small glass bottle. Figure 3 a) After vacuuming, sealing, and heating to 50°C, parts of the fabric turn blue. Figure 3 (b) When heated to 55°C, the area of ​​the fabric turning blue increases ( Figure 3 c), as the temperature increases to 60 ℃, the area of ​​the fabric turning blue in the vial becomes larger. Figure 3 d), when the temperature is heated to 70 ℃, the fabric almost completely turns light blue ( Figure 3 e) Unscrew the bottle to let air in, and you'll find that the blue fabric quickly turns back to its original purplish-red color. Figure 3 f).

[0044] Example 3

[0045] Step 1: Soak the cotton fabric in an ethanol solution, then wash it with water, dry it, and set it aside.

[0046] Step 2: Weigh 0.5 g of the K6Na prepared in Example 1. 17 [H3{Co(H2O)3}2(P4Nb9O 40 )2]·24H2O is dissolved in 2 mL of water, 0.1 g of binder 939 and 7.4 g of 5wt% sodium alginate are added, and an appropriate amount of water is added to make up to a total mass of 10 g of slurry. Stir continuously until it becomes viscous.

[0047] Step 3: Print the slurry prepared in step 2 onto the fabric obtained in step 1 using a magnetic rod printing machine. Pre-dry at 80 ℃ for 3 min, then bake at 90 ℃ for 3 min to obtain a reversible moisture-sensitive color-changing fabric.

[0048] Figure 4 The color change of the fabric obtained in Example 3 during the experiment is shown.

[0049] The specific experimental procedure is as follows:

[0050] The pink reversible moisture-sensitive color-changing fabric obtained in Example 3 was placed in a small glass bottle. Figure 4 a) After vacuuming, sealing, and heating to 50°C, parts of the fabric turn blue. Figure 4 (b) When heated to 55°C, the area of ​​the fabric turning blue increases ( Figure 4 c), as the temperature increases to 60 ℃, the area of ​​the fabric turning blue in the vial becomes larger. Figure 4 d), when the temperature is heated to 70 ℃, the fabric almost completely turns light blue ( Figure 4 e) Unscrew the bottle to let air in, and you'll find that the blue fabric quickly turns back to its original purplish-red color. Figure 4 f).

[0051] The above process was repeated 5 times, and it was found that both the powder sample and the cotton fabric could achieve good color change behavior, showing good fatigue resistance.

[0052] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for preparing a reversible moisture-sensitive color-changing fabric, characterized in that, Includes the following steps: S1. Dissolve the moisture-sensitive compound in water, add the adhesive and printing paste, then add more water and stir continuously until a viscous consistency is reached to obtain a slurry; the molecular formula of the moisture-sensitive compound is K6Na. 17 [H3{Co(H2O)3}2(P4Nb9O 40 )2]·24H2O; S2. The slurry is printed onto a cotton fabric that has been washed and dried, and then pre-dried and baked to obtain a reversible moisture-sensitive color-changing fabric loaded with a moisture-sensitive compound.

2. The preparation method according to claim 1, characterized in that, The adhesive is an acrylic polyurethane copolymer adhesive.

3. The preparation method according to claim 1, characterized in that, The printing paste is a 5wt% sodium alginate aqueous solution.

4. The preparation method according to claim 1, characterized in that, In step S1, the amounts of the compound, adhesive, and printing paste are as follows: each 10g of paste contains 0.2~0.8g of the compound, 0.05~0.1g of the adhesive, and 5~8g of the printing paste.

5. The preparation method according to claim 1, characterized in that, In step S2, the pre-baking temperature is 70~80 ℃ and the time is 1~10 min.

6. The preparation method according to claim 1, characterized in that, In step S2, the baking temperature is 90~120 ℃ and the baking time is 1~10 min.

7. A reversible moisture-sensitive color-changing fabric prepared by the preparation method according to any one of claims 1-6.

8. The reversible moisture-sensitive color-changing fabric as described in claim 7, characterized in that, When the moisture-sensitive compound loaded on the reversible moisture-sensitive fabric is in a hydrated state, the reversible moisture-sensitive fabric appears purplish-red; when the moisture-sensitive compound loaded on the reversible moisture-sensitive fabric is in a dehydrated state, the reversible moisture-sensitive fabric appears blue.

9. The reversible moisture-sensitive color-changing fabric as described in claim 7, characterized in that, The reversible moisture-sensitive color-changing fabric appears purplish-red in the air and remains blue in an anhydrous environment at 50-70°C.

10. The application of the reversible moisture-sensitive color-changing fabric as described in claim 7 in a humidity sensor.

Images