A method for preparing a phase change material-based jacquard fabric

Abstract

This invention relates to the textile field. A method for preparing a phase change material (PCM) imitation jacquard fabric includes the following steps: Step 1: Uniformly coating a polyurethane expanded microsphere dispersion onto a fabric; Step 2: Printing a printing paste containing PCM phase change material onto the pretreated fabric to obtain a printed fabric; then, curing and cooling to obtain a flat printed fabric; Step 3: Heating the flat printed fabric, causing the polyurethane expanded microspheres in the inner area of ​​the pattern to expand due to heat, while the polyurethane expanded microspheres in the outer area of ​​the pattern remain in their original state; then, naturally cooling to room temperature to obtain a phase change material imitation jacquard fabric with varying textures. This invention achieves a three-dimensional pattern through the synergistic effect of polyurethane expanded microspheres and PCM phase change material, characterized by "internal thermal expansion and external heat absorption inhibition."

Description

Technical Field

[0001] This invention relates to the textile field, and more specifically to fabrics. Background Technology

[0002] According to the printing process, printing can be mainly classified into the following types:

[0003] 1. Direct printing: The prepared printing ink is directly printed onto the fabric. This is the simplest and most commonly used printing process.

[0004] 2. Discharge printing: also known as engraving, refers to a printing method that uses a discharge agent to print on colored fabrics, destroying the pigments that have already been dyed, thereby obtaining various patterns and designs.

[0005] 3. Resist printing: Chemical agents or waxy resins that prevent dye penetration are printed onto white fabric, and then the base color is applied to highlight the white pattern.

[0006] Traditional printing techniques result in printed fabrics where the printed and unprinted areas are on the same plane, making the fabric overall flat. If the printed areas could protrude beyond the unprinted areas, creating a textured, three-dimensional structure, it would undoubtedly increase the visual impact of the printed areas and improve the fabric's breathability. Summary of the Invention

[0007] The purpose of this invention is to provide a method for preparing a phase change material imitation jacquard fabric, so as to prepare a three-dimensional printed fabric in which the printed part protrudes outside the non-printed part.

[0008] The technical problem solved by this invention can be achieved by the following technical solutions:

[0009] A method for preparing a phase change material-based jacquard fabric includes the following steps:

[0010] Step 1: Coat the polyurethane expanded microsphere dispersion evenly onto the fabric, remove the surface moisture, and obtain the pretreated fabric. The polyurethane expanded microspheres in the polyurethane expanded microsphere dispersion are not expanded, and the particle size of the polyurethane expanded microspheres is 10-20um and the true density is 1000-1300kg / m³.

[0011] Step 2: Mix PCM phase change material and water-based polyurethane adhesive at a mass ratio of 7:3 to obtain printing paste; prepare a pattern mask, making the outer area of ​​the pattern hollow and the inner area closed; use the pattern mask to print the printing paste onto the pretreated fabric to obtain printed fabric; then, cure and cool the printed fabric to obtain flat printed fabric.

[0012] Step 3: Heat the flat printed fabric to cause the polyurethane expanded microspheres in the inner area of ​​the pattern to expand, while the polyurethane expanded microspheres in the outer area of ​​the pattern remain in their original shape; then, let it cool naturally to room temperature to obtain a phase change material imitation jacquard fabric with uneven texture.

[0013] Preferably, the critical expansion temperature of the outer shell material of the polyurethane expandable microspheres is 45°C. In step three, the flat printed fabric is placed on an infrared heating platform for heating. The infrared wavelength of the infrared heating platform is 8-12µm, the heating temperature is 50°C±1°C, and the heating time is 30-60 seconds.

[0014] Preferably, before step one, the fabric is placed in deionized water, and a neutral detergent with a mass concentration of 0.5-1.0% is added. The fabric is then ultrasonically cleaned at 40-60°C for 10-30 minutes to remove surface impurities. Then, the fabric is rinsed with deionized water until no residue remains, and then dried in a vacuum oven at 100°C until the fabric moisture content is below 0.5%.

[0015] Preferably, in step one, the polyurethane expanded microsphere dispersion is uniformly coated onto the fabric using a doctor blade coater, with a doctor blade angle of 15-30°, a coating speed of 10-20 m / min, and a coating thickness of 50-100 μm.

[0016] Preferably, in step two, a screen printing machine is used for printing, and the thickness of the printed layer is 50-80um.

[0017] Preferably, in step one, the solid content of the polyurethane expanded microspheres in the polyurethane expanded microsphere dispersion is 5-15 wt%, the solid content of the polyurethane adhesive is 0.5-1 wt%, and the solid content of the sodium polyacrylate dispersant is 0.5-1 wt%.

[0018] Preferably, in step two, the particle size of the PCM phase change material is 50-100 μm, the latent heat enthalpy is 150-200 J / g, and the melting phase change temperature is 38 °C.

[0019] Preferably, in step two, the printed fabric is first cured in a 40°C oven for 30 minutes, and then cooled in an environment of 10-20°C.

[0020] Beneficial effects: This invention achieves a three-dimensional floral pattern (height difference can reach 100-300um) through the synergistic effect of polyurethane expandable microspheres and PCM phase change material, characterized by "internal thermal expansion and external heat absorption and suppression". This mechanism represents a technological breakthrough in the textile field, combining thermal expansion and phase change temperature regulation for the first time. Attached Figure Description

[0021] Figure 1 A photograph of the phase change material-based jacquard fabric obtained in Example 1;

[0022] Figure 2This is a microstructure diagram of the phase change material imitation jacquard fabric obtained in Example 1. Detailed Implementation

[0023] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with the accompanying drawings.

[0024] A method for preparing a phase change material-based jacquard fabric includes the following steps:

[0025] Step 1: Coat the polyurethane expanded microsphere dispersion evenly onto the fabric, remove the surface moisture, and obtain the pretreated fabric. The polyurethane expanded microspheres in the polyurethane expanded microsphere dispersion are not expanded, and the particle size of the polyurethane expanded microspheres is 10-20um and the true density is 1000-1300kg / m³.

[0026] Step 2: Mix PCM phase change material and water-based polyurethane adhesive at a mass ratio of 7:3 to obtain printing paste; prepare a pattern mask, making the outer area of ​​the pattern hollow and the inner area closed; use the pattern mask to print the printing paste onto the pretreated fabric to obtain printed fabric; then, cure and cool the printed fabric to obtain flat printed fabric.

[0027] Step 3: Heat the flat printed fabric to cause the polyurethane expanded microspheres in the inner area of ​​the pattern to expand, while the polyurethane expanded microspheres in the outer area of ​​the pattern remain in their original shape; then, let it cool naturally to room temperature to obtain a phase change material imitation jacquard fabric with uneven texture.

[0028] Example 1, Step 1: A doctor blade coater is used to uniformly coat the fabric with a polyurethane expanded microsphere dispersion. The doctor blade angle is 15°, the coating speed is 10 m / min, and the coating thickness is controlled at 50 μm (wet film). The coated fabric is then placed in a 40°C oven for pre-drying for 10 minutes to remove surface moisture, forming a pre-attached layer of polyurethane expanded microspheres. Step 2: Based on the design, the pattern is drawn using CAD software. A pattern mask (made of polyester film or metal mesh) is prepared by laser engraving, ensuring that the outer area of ​​the pattern is hollowed out and the inner area is closed. PCM phase change material is mixed with water-based polyurethane adhesive (mass ratio 7:3) to prepare PCM printing paste. A screen printing machine is used to ensure a PCM printing layer thickness of 50 μm. The printed fabric is then placed in a 40°C oven for curing for 30 minutes to ensure a strong bond between the PCM phase change material and the fabric. The fabric is then cooled at 20°C to ensure exothermic crystallization and curing of the PCM material. The PCM phase change material has a particle size of 50 μm, a latent heat enthalpy of 150 J / g, and a melting phase change temperature of 38℃. Step 3: Place the fabric on an infrared heating platform (wavelength 8 μm), and precisely control the heating temperature to 50℃ (±1℃) using a temperature control system for 30 seconds. Internal expansion: Due to the lack of PCM coverage in the internal area of ​​the pattern, the internal gas pressure of the polyurethane expanded microspheres increases after heating, the outer shell softens, and the volume expands to 3 times its original size. Expansion inhibition in the outer area: The PCM phase change material around the pattern absorbs heat and undergoes a phase change (solid → liquid), absorbing a large amount of heat and maintaining the local temperature below 40℃. The polyurethane microspheres cannot reach the expansion temperature (Tg=45℃) and remain in their original state. Cooling and shaping: After stopping heating, allow the fabric to cool naturally to room temperature. The outer shell of the polyurethane microspheres hardens, fixing the expanded three-dimensional structure and forming a three-dimensional imitation jacquard patterned fabric with uneven texture. Example 1 shows that the height of the jacquard patterned fabric is 100 μm.

[0029] Example 2, Step 1: A doctor blade coater is used to uniformly coat the polyurethane expanded microsphere dispersion onto the fabric. The doctor blade angle is 30°, the coating speed is 20 m / min, and the coating thickness is controlled at 100 μm (wet film). The coated fabric is then placed in a 40°C oven for pre-drying for 15 minutes to remove surface moisture and form a pre-attached layer of polyurethane expanded microspheres. Step 2: According to the design, the pattern is drawn using CAD software, and a pattern mask (made of polyester film or metal mesh) is prepared by laser engraving, ensuring that the outer area of ​​the pattern is hollowed out and the inner area is closed. The PCM phase change material is mixed with an aqueous polyurethane adhesive (mass ratio 7:3) to prepare the PCM printing paste. A screen printing machine is used to ensure that the PCM printing layer thickness is 80 μm. The printed fabric is then placed in a 40°C oven for curing for 30 minutes to ensure a strong bond between the PCM phase change material and the fabric. The fabric is then cooled in a 10°C environment to ensure that the PCM material undergoes exothermic crystallization and curing. The PCM phase change material has a particle size of 100 μm, a latent heat enthalpy of 200 J / g, and a melting phase change temperature of 38℃. Step 3: The fabric is placed on an infrared heating platform (wavelength 12 μm), and the heating temperature is precisely controlled to 50℃ (±1℃) using a temperature control system for 60 seconds. Internal expansion: Due to the lack of PCM coverage in the internal area of ​​the pattern, the internal gas pressure of the polyurethane expanded microspheres increases after heating, the outer shell softens, and the volume expands to 5 times its original size. Expansion inhibition in the outer area: The PCM phase change of the outer area of ​​the pattern absorbs heat and undergoes a phase change (solid → liquid), absorbing a large amount of heat, keeping the local temperature below 40℃. The polyurethane microspheres cannot reach the expansion temperature (Tg=45℃) and remain in their original state. Cooling and shaping: After heating is stopped, the fabric is allowed to cool naturally to room temperature. The outer shell of the polyurethane microspheres hardens, fixing the expanded three-dimensional structure and forming a three-dimensional imitation jacquard patterned fabric with uneven texture. Example 2 shows that the height of the jacquard patterned fabric is 300 μm.

[0030] The polyurethane expanded microsphere dispersion of the present invention contains 5-15 wt% solid content of microspheres, 0.5-1 wt% solid content of polyurethane adhesive, and 0.5-1 wt% solid content of sodium polyacrylate dispersant. The microspheres have a particle size of 10-20 μm when unexpanded, a true density of 1000-1300 kg / m³, and a particle size of 40-50 μm after expansion. The Tg temperature (critical expansion temperature) of the microsphere shell material is 45°C. In the two embodiments above, in Example 1, the polyurethane expanded microsphere dispersion contains 15 wt% solid content of microspheres, 1 wt% solid content of polyurethane adhesive, and 1 wt% solid content of sodium polyacrylate dispersant. The microspheres have a particle size of 10 μm when unexpanded, a true density of 1000 kg / m³, and a particle size of 40 μm after expansion. In Example 2, the polyurethane expanded microsphere dispersion contained 5 wt% solid content of microspheres, 0.5 wt% solid content of polyurethane adhesive, and 0.5 wt% solid content of sodium polyacrylate dispersant. The microspheres had a particle size of 20 μm and a true density of 1300 kg / m³ before expansion, and a particle size of 50 μm after expansion.

[0031] Before step one, the fabric is first placed in deionized water, and a neutral detergent with a mass concentration of 0.5-1.0% is added. The mixture is then ultrasonically cleaned at 40-60°C for 10-30 minutes (frequency 30-50kHz) to remove surface grease, dust, and other impurities. It is then rinsed with deionized water until no residue remains, and dried in a 100°C vacuum oven for 2 hours to ensure the fabric's moisture content is below 0.5%. In both embodiments, it is preferred that the neutral detergent has a mass concentration of 0.8%, and the ultrasonic cleaning is performed at 60°C for 30 minutes (frequency 50kHz).

[0032] The core material of the PCM phase change material in this invention is preferably an octadecane-based substance, and the wall material is preferably a polyurethane-based substance. The PCM phase change material used in Example 1 is from Shanghai Xinwu Chemical Co., Ltd., model: XW-PCM50; the PCM phase change material used in Example 1 is from Shanghai Xinwu Chemical Co., Ltd., model: XW-PCM100. The core material of the polyurethane microspheres in this invention is preferably an n-hexane-based substance, and the wall material is preferably a polyurethane-based substance. The polyurethane microspheres used in Example 1 are from Shanghai Xinwu Chemical Co., Ltd., model: XW-PUM-10; the polyurethane microspheres used in Example 2 are from Shanghai Xinwu Chemical Co., Ltd., model: XW-PUM-20.

[0033] The waterborne polyurethane adhesive used in the examples is from Shanghai Xinwu Chemical Co., Ltd., model XW-PUW-501; the polyurethane adhesive is from Ausjia Materials Technology Co., Ltd., model A-PU-802; the sodium polyacrylate dispersant is from Shanghai Nuoke Chemical New Materials Co., Ltd., model NK-PAAS-20; and the neutral detergent is from Ausjia Materials Technology Co., Ltd., model A-NC-100.

[0034] The photograph of the three-dimensional imitation jacquard patterned fabric obtained in Example 1 is shown below. Figure 1 As shown, the microstructure is as follows Figure 2 As shown, Figure 2 The linear shapes are fabric fibers 1, and the spherical shapes are polyurethane expanded microspheres 2.

[0035] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A method for producing a phase change material jacquard fabric, characterized by, The method comprises the following steps: Step 1: uniformly coating a polyurethane expanded microsphere dispersion liquid on a fabric, and obtaining a pretreated fabric after removing surface moisture, wherein the polyurethane expanded microspheres in the polyurethane expanded microsphere dispersion liquid are not expanded, and the particle size of the polyurethane expanded microspheres is 10-20 μm and the true density is 1000-1300 kg / m³; Step 2: mixing a PCM phase change material and a water-based polyurethane adhesive according to a mass ratio of 7:3 to obtain a printing paste; preparing a pattern mask, making the peripheral region of the pattern hollow and the internal region closed; printing the printing paste on the pretreated fabric by using the pattern mask to obtain a printed fabric; and then, curing and cooling the printed fabric to obtain a planar printed fabric; Step 3: heating the planar printed fabric, so that the polyurethane expanded microspheres in the internal region of the pattern are expanded by heat and the polyurethane expanded microspheres in the external region of the pattern remain unchanged; and then, naturally cooling to room temperature to obtain a phase change material jacquard fabric with uneven concave-convex.

2. The method for preparing a phase change material Jacquard fabric according to claim 1, characterized in that, The expansion critical temperature of the polyurethane shell material is 45℃, and in Step 3, the planar printed fabric is placed on an infrared heating platform for heating, the infrared wavelength of the infrared heating platform is 8-12 μm, the heating temperature is 50℃±1℃, and the heating time is 30-60 seconds.

3. The method for preparing a phase change material imitation jacquard fabric according to claim 1, characterized in that, Before Step 1, the fabric is first placed in deionized water, a neutral detergent with a mass concentration of 0.5-1.0% is added, and the fabric is ultrasonically cleaned at 40-60℃ for 10-30 minutes to remove surface impurities; and then, the fabric is rinsed with deionized water until no residue is left and is dried in a 100℃ vacuum oven until the water content of the fabric is less than 0.5%.

4. The method for preparing a phase change material imitation jacquard fabric according to claim 1, characterized in that, In Step 1, the polyurethane expanded microsphere dispersion liquid is uniformly coated on the fabric by using a doctor blade coater, the doctor blade angle is 15-30°, the coating speed is 10-20 m / min, and the coating thickness is 50-100 μm.

5. The method for preparing a phase change material imitation jacquard fabric according to claim 1, characterized in that, In Step 2, the printing is performed by using a screen printing machine, and the printing layer thickness is 50-80 μm.

6. The method for preparing a phase change material imitation jacquard fabric according to claim 1, characterized in that, In Step 1, the solid content of the polyurethane expanded microspheres in the polyurethane expanded microsphere dispersion liquid is 5-15 wt%, the solid content of the polyurethane adhesive is 0.5-1 wt%, and the solid content of the sodium polyacrylate dispersant is 0.5-1 wt%.

7. The method for preparing a phase change material imitation jacquard fabric according to claim 1, characterized in that, In Step 2, the particle size of the PCM phase change material is 50-100 μm, the latent heat enthalpy value is 150-200 J / g, and the melting phase change temperature is 38℃.

8. The method for preparing a phase change material imitation jacquard fabric according to claim 1, characterized in that, In Step 2, the printed fabric is first placed in a 40℃ oven for curing for 30 minutes, and then is placed in a 10-20℃ environment for cooling.

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