A thermal clothing material and a method of making the same

Abstract

The application belongs to the technical field of clothing and textile, and provides a warm-keeping clothing material and a preparation method thereof, which comprises the following steps: mixing polyimide powder, foaming powder, adhesive, cross-linking agent and solvent to prepare foaming slurry; the foaming powder is thermoplastic expandable microsphere foaming powder; the foaming slurry is applied to one surface of clothing fabric by printing or coating; after high-temperature baking, foaming printed fabric is obtained; the printed and coated surface of the foaming printed fabric is treated by three-dimensional embossing to form a certain depth of concave-convex structure, and the warm-keeping clothing material is obtained. The textile fabric prepared by the application has excellent temperature-locking and warm-keeping performance, thereby significantly improving the warm-keeping experience of the wearer of the clothing.

Description

Technical Field

[0001] This invention belongs to the field of clothing and textile technology, and relates to a thermal clothing material and its preparation method. Background Technology

[0002] Currently, the main technical approach to improving the warmth retention of winter clothing is to reduce or slow down the conduction of heat from the body inside the clothing to the external environment, that is, to reduce or slow down heat loss from the body through warm clothing. Air is a poor conductor of heat, and still air is considered the warmest substance; down jackets, cotton-padded jackets, and fleece products improve their warmth retention by increasing the amount of air inside the textile material, thereby reducing heat conduction.

[0003] Existing technologies have reported methods to improve the thermal insulation performance of fabrics by adding powder materials such as graphene to the fabric surface. For example, Chinese patent document CN 109235085 A discloses a graphene paste-printed fabric, its preparation method, and related apparel. This patent document discloses a graphene paste that is printed onto fabric; it mainly utilizes the far-infrared properties of graphene to improve the fabric's heating rate or thermal insulation performance, thereby providing a feeling of warmth to the human body. However, in reality, the fabric's thermal insulation rate and clo value are not significantly improved, and the wearer's actual experience of warmth is not noticeable. Summary of the Invention

[0004] In view of this, the present invention provides a thermal clothing material and a method for preparing the same. The textile fabric prepared by the present invention has excellent heat-locking and heat-preserving properties, thereby significantly improving the warmth experience of the wearer.

[0005] This invention provides a method for preparing a thermal clothing material, comprising the following steps:

[0006] Polyimide powder, foaming powder, adhesive, crosslinking agent and solvent are mixed to prepare a foaming slurry; the foaming powder is thermoplastic expandable microsphere foaming powder;

[0007] The foaming paste is applied to one surface of a garment fabric by printing or coating, and after being baked at high temperature, a foamed printed fabric is obtained.

[0008] The surface of the printed coating of the foamed printed fabric is embossed to form a textured structure of a certain depth, resulting in a thermal clothing material.

[0009] Preferably, the polyimide powder has a mass content of 5% to 10% in the foaming slurry.

[0010] Preferably, the foaming slurry is prepared according to the following specific operations:

[0011] The polyimide powder was dissolved in an organic solvent to obtain a mixture.

[0012] According to the mass ratio, 5-20 parts of the mixture, 5-10 parts of foaming powder, 90-100 parts of adhesive, 5-10 parts of crosslinking agent and water are mixed and stirred to obtain foaming slurry.

[0013] Preferably, the polyimide powder has an average particle size of 1–10 μm; the organic solvent is dimethylacetamide and / or dimethylformamide;

[0014] Preferably, the adhesive is a water-based polyurethane adhesive; the crosslinking agent is a water-based blocked aliphatic polyisocyanate crosslinking agent.

[0015] Preferably, the printing method specifically involves: applying the foaming paste to one surface of the garment fabric using a screen printing plate; drying and then baking at high temperature to obtain the foamed printed fabric.

[0016] Preferably, the mesh size of the screen printing plate is 100-200 mesh; the main component of the garment fabric is chemical fiber, with a weight of 30-100 g / m². 2 The high-temperature baking temperature is 80-150℃.

[0017] Preferably, the three-dimensional embossing process is carried out using a three-dimensional embossing roller at a temperature of 180–200°C and a pressure of 2.5–4.0 MPa.

[0018] Preferably, the pattern of the three-dimensional embossing roller is a closed pattern array with a three-dimensional depth of 1-2 mm.

[0019] This invention provides a thermal clothing material, which is obtained by the preparation method described above, and is used as a clothing lining.

[0020] Polyimide (PI), as a special engineering material, possesses strong mechanical properties, excellent insulation, radiation resistance, good thermal insulation, and high stability, making it widely used in aerospace, electronics, and semiconductor engineering. However, due to limited production capacity, its cost is very high, and many technical challenges in spinning and dyeing have not been fully overcome, thus significantly limiting the commercial application of PI materials. Polyimide has a thermal conductivity close to that of air, making it an ideal material for clothing insulation. Therefore, how to apply polyimide materials to clothing in a more convenient and cost-effective manner is a pressing issue that needs to be addressed.

[0021] Compared to traditional clothing lining materials, this invention prepares a thermal clothing material with a surface containing polyimide, which can be used as a clothing lining. In the preparation method of this invention, a polyimide foam coating slurry containing PI powder, thermoplastic expandable microsphere foaming powder, adhesive, and other components is first prepared. Then, one surface of the clothing fabric is treated with this foam coating slurry for printing, resulting in a polyimide-containing foam printed fabric. The printed coating surface of the foam printed fabric is then subjected to three-dimensional embossing to form a textured structure of a certain depth, resulting in the thermal clothing material. The thermal clothing material obtained by this invention has a foam printed layer of a certain thickness on its surface, in which polyimide is added. Since polyimide is a low thermal conductivity material, with a thermal conductivity close to that of air, it can reduce the heat conduction performance of the thermal clothing material. Simultaneously, the foam print contains many cavities, which help to trap air, reduce heat conduction, and improve the thermal insulation performance of the clothing material. Furthermore, the resulting foamed printed semi-finished material undergoes a three-dimensional embossing process to form a textured structure with a certain depth. This textured structure further increases the air content inside the garment, enhancing the overall warmth retention of the material. The textile fabric produced by this invention possesses excellent heat-locking and warmth-retaining properties, thereby significantly improving the warmth experience for the wearer. Attached Figure Description

[0022] Figure 1 This is a pattern diagram of the printing process in Embodiment 1 of the present invention;

[0023] Figure 2 This is a pattern diagram of the embossed material obtained in Example 1 of the present invention;

[0024] Figure 3 This is the pattern diagram of the printing process in Embodiment 2 of the present invention;

[0025] Figure 4 This is a pattern diagram of the embossed material obtained in Example 2 of the present invention. Detailed Implementation

[0026] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be described in detail below with reference to specific embodiments. The description in this part is only exemplary and explanatory, and should not be used to limit the scope of protection of the present invention in any way.

[0027] This invention provides a method for preparing a thermal clothing material, comprising the following steps:

[0028] Polyimide powder, foaming powder, adhesive, crosslinking agent and solvent are mixed to prepare a foaming slurry; the foaming powder is thermoplastic expandable microsphere foaming powder;

[0029] The foaming paste is applied to one surface of a garment fabric by printing or coating, and after being baked at high temperature, a foamed printed fabric is obtained.

[0030] The surface of the printed coating of the foamed printed fabric is embossed to form a textured structure of a certain depth, resulting in a thermal clothing material.

[0031] The textile fabric produced by this invention has excellent heat-locking and warmth-preserving properties, thereby significantly improving the warmth experience of the wearer.

[0032] This invention first prepares a polyimide foam coating slurry. The specific preparation process is as follows: polyimide powder is dissolved in an organic solvent to obtain a mixture. The polyimide powder preferably has an average particle size of 1–10 μm, more preferably 4–5 μm, a thermal conductivity of PI of 0.032 J / (m·℃), and an average molecular weight >100,000 g / mol. Commercially available products are acceptable, such as polyimide powder produced by Shenzhen MicroNano Co., Ltd. The organic solvent is preferably dimethylacetamide (DMAC) and / or dimethylformamide (DMF), more preferably dimethylformamide.

[0033] Then, the obtained polyimide powder organic solvent mixture is mixed with foaming powder, binder, and crosslinking agent, and water is added. Preferably, the mixture is stirred using an electric stirrer at a speed of 800–1000 r / min for 5–10 min to obtain a polyimide foamed coating / printing paste (which can be referred to as foaming paste). By weight, the polyimide foaming paste consists of: 8–10 parts water, 90–100 parts binder, 5–10 parts thermoplastic expandable microsphere foaming powder, 5–10 parts crosslinking agent, and 5–20 parts of the above mixture. The overall room temperature viscosity of the foaming paste is 14000–15000 mPa·s; dyes or pigments can also be added according to design requirements. Furthermore, the printing paste and coating paste in this application can use the same process parameters.

[0034] In an embodiment of the present invention, the foaming slurry contains 5% to 10% polyimide powder, and the specific addition amount can be 6% to 9%. On the one hand, based on the PI slurry configuration, too much addition will cause PI to deposit in the slurry and disperse unevenly, which is not conducive to the subsequent production and processing of thermal insulation materials. On the other hand, the improvement in thermal insulation effect is no longer significant when the addition amount is above 10%. The embodiment of the present invention takes into account the above-mentioned range of PI addition amount in consideration of cost factors.

[0035] This invention involves dissolving polyimide powder and mixing it with polyurethane resin, foaming powder, etc., to prepare a polyimide foaming slurry. The foaming powder is a thermoplastic expandable microsphere foaming powder; it is a dry microsphere, and AkzoNobel's Expansionl 461WE 40d36 product can be used. This product has a core-shell structure, with an outer shell of thermoplastic acrylic resin polymer and a core of hollow spherical microparticles composed of alkane gases. Upon heating, it expands to an average particle size of 40 μm. The use of thermoplastic expandable microsphere foaming powder as the foaming agent in this invention is primarily due to considerations for subsequent 3D embossing processes. Other chemically foamed printing coatings are prone to cavity collapse after embossing, while the foamed microspheres used in this invention have a single spherical structure, resulting in superior retention of the foamed cavity.

[0036] In an embodiment of the present invention, 5-20 parts by weight of the mixture, 5-10 parts by weight of thermoplastic expandable microsphere foaming powder, 90-100 parts by weight of adhesive, 5-10 parts by weight of crosslinking agent, and water are mixed and stirred to obtain a foaming slurry. The amount of adhesive used can be 92-98 parts, preferably a water-based polyurethane resin adhesive, which has advantages such as good flexibility, high bonding strength, and low odor. Specifically, the polyurethane resin solid content of the adhesive can be 57-59%, the viscosity ≥100 mPa·s, and the pH value 6-9. Commercially available products can be used, such as Anhui Anda Huatai AH-1619, with a specific gravity of 1.06±0.02 g / cm³. 3 .

[0037] Furthermore, the crosslinking agent is preferably a water-based blocked aliphatic polyisocyanate crosslinking agent, which has good hardness and elasticity. Preferably, the water-based blocked aliphatic polyisocyanate crosslinking agent has a solid content of 11.5±0.5%, a viscosity of <100 mPa·s, and a pH value of 6.5-8.5, and can be a commercially available product such as Covestro Imprafix 2794.

[0038] After preparing the polyimide foaming paste, the embodiments of the present invention perform printing or coating treatment. Specifically, the embodiments of the present invention use a screen printing plate to coat the foaming paste onto one surface of a garment fabric; after drying, it is then baked at high temperature to obtain a polyimide-containing foamed printed fabric, while direct coating treatment can obtain a polyimide-containing foamed coated fabric. In some embodiments, the application amount of the printing foaming paste is 10 g / m². 2 ~12g / m 2 In other embodiments, the amount of coating foaming slurry applied is 14 g / m³. 2 ~16g / m 2 .

[0039] The structure of the garment fabric material can be a knitted structure, such as plain knit fabric, or a woven fabric, such as spring spun yarn (90g / m²). 2 It can also be a non-woven interlining with a weight of 30g / m². 2 ~40g / m 2 The main component of the clothing fabric is chemical fiber, including one or more of the following fiber materials: polyester, nylon, spandex, etc.

[0040] The embodiments of this invention preferably employ screen printing, which yields better results. The screen printing plate for screen printing preferably has an aperture of 100-200 mesh, more preferably 100 mesh. The drying temperature is preferably 70-80℃, and the drying time is preferably 1-5 minutes, more preferably 3-4 minutes; the high-temperature baking temperature can be 80-150℃, preferably 130-140℃, further ensuring a firm bond between the foamed print and the material. The foamed print layer of a certain thickness formed in the embodiments of this invention contains numerous cavity structures, which helps to trap air, reduce heat conduction, and improve the warmth retention of clothing materials.

[0041] In this embodiment of the invention, the foamed printed coating fabric obtained above is processed by a three-dimensional embossing device to prepare an embossed material with a three-dimensional concave-convex structure according to a specific pattern, that is, a clothing material containing a polyimide foamed printed coating with a three-dimensional concave-convex structure.

[0042] In embodiments of the present invention, the three-dimensional embossing process is performed using a three-dimensional embossing roller. The preferred temperature is 180–200°C, the preferred pressure is 2.5–4.0 MPa, and the embossing speed is 1.5 m / min–3.0 m / min. The pattern of the three-dimensional embossing roller is preferably a uniform array of closed graphics (non-continuous patterns), such as individual graphics being circles, ellipses, quadrilaterals, or other polygons. The depth of the embossed structure is generally 1 mm–2 mm, which can further increase the air content inside the garment and improve the overall warmth retention of the material.

[0043] Furthermore, the three-dimensional embossing process described in this embodiment of the invention is only performed on a portion of the surface of the foamed printed fabric, maintaining the complete foam cavity structure in areas not covered by the embossing process. Simultaneously, the raised three-dimensional structure formed by this embossing process is a macroscopic structure, capable of storing a larger amount of air; therefore, embossing does not reduce the warmth retention performance.

[0044] This invention provides a thermal clothing material, obtained by the preparation method described above, for use as a garment lining. The thermal clothing material provided in this embodiment has a specific three-dimensional embossed structure on its surface and contains a polyimide foamed layered structure, exhibiting excellent thermal insulation properties.

[0045] This invention involves preparing a polyimide foaming paste, applying it to garment fabric via coating or printing, and then performing a three-dimensional embossing process to obtain a polyimide foamed printed coating three-dimensional embossed garment material. This invention primarily utilizes the low thermal conductivity of polyimide and the characteristics of foamed printing (or foamed coating) and three-dimensional embossing structures, which can increase the internal air content of the garment material and reduce its heat transfer rate, thus giving the fabric excellent heat retention and warmth preservation properties. Furthermore, the method of this invention is simple to operate, low in cost, and conducive to industrial application.

[0046] The present invention will be further described in detail below with reference to embodiments. The embodiments described herein are only for the purpose of understanding the present invention, and the implementation of the present invention is not limited thereto. The raw materials used in the embodiments of the present invention are commercially available products.

[0047] Example 1

[0048] The thermal clothing material and its production method described in this embodiment are as follows:

[0049] (1) Preparation of polyimide foaming slurry

[0050] a. Dissolve polyimide powder in an organic solvent to obtain a mixture; wherein the polyimide powder is produced by Shenzhen MicroNano Co., Ltd. and has an average particle size of 4 μm; the organic solvent is dimethylformamide.

[0051] b. The mixture is then mixed with foaming powder, binder, crosslinking agent and water, and stirred with an electric stirrer at a speed of 800-1000 r / min for 5 min-10 min to obtain polyimide foaming slurry; by mass, the composition of polyimide foaming slurry is: 10 parts water, 100 parts binder, 9 parts thermoplastic expandable microsphere foaming powder, 9 parts crosslinking agent and 20 parts mixture.

[0052] The adhesive is a water-based polyurethane resin adhesive, Anhui Anda Huatai AH-1619, with a solid content of 58±1%, viscosity ≥100 mPa.s, pH value 6-9, and specific gravity 1.06±0.02 g / cm³. 3 .

[0053] The crosslinking agent is an aqueous blocked aliphatic polyisocyanate crosslinking agent, Covestro Imprafix 2794, with a solid content of 11.5±0.5%, viscosity <100 mPa.s, and pH value of 6.5-8.5.

[0054] The foaming powder is a thermoplastic expandable microsphere foaming powder, a dry microsphere, AkzoNobel Expansionl 461WE 40d36, which has a core-shell structure. The outer shell is a thermoplastic acrylic resin polymer, and the core is a hollow spherical microparticle composed of alkane gas. It expands when heated and can reach an average particle size of 40μm.

[0055] (2) Printing

[0056] The polyimide foaming paste is coated onto a nonwoven fabric by screen printing, dried, and then baked to obtain a polyimide foaming printing material.

[0057] Clothing fabric material: Non-woven fabric (100% polyester), weight 40g / m² 2 ;

[0058] The screen printing mesh has a 100-mesh aperture; the application rate of the printing foaming paste is 10 g / m². 2 ~12g / m 2 ;

[0059] The drying temperature is 70℃~80℃; the drying time is 3~4 minutes;

[0060] The baking temperature is 130℃~140℃;

[0061] The printed pattern is a dense dot pattern, such as... Figure 1 As shown.

[0062] (3) Embossing

[0063] The printed nonwoven fabric obtained above is processed through a three-dimensional embossing device to prepare an embossed material with a three-dimensional concave-convex structure according to a specific floral pattern.

[0064] The temperature of the three-dimensional embossing roller in the embossing process is 190℃, the pressure is 3.5 MPa, and the embossing speed is 2.0 m / min.

[0065] The three-dimensional embossed pattern consists of a uniform hexagonal array with a pattern depth of approximately 1.5 mm. Figure 2 As shown.

[0066] Example 2

[0067] The thermal clothing material and its production method described in this embodiment are as follows:

[0068] (1) Preparation of polyimide foaming slurry

[0069] a. Dissolve polyimide powder in an organic solvent to obtain a mixture; wherein the polyimide powder is produced by Shenzhen MicroNano Co., Ltd. and has an average particle size of 4 μm; the organic solvent is dimethylformamide.

[0070] b. The mixture is then mixed with foaming powder, binder, crosslinking agent and water, and stirred with an electric stirrer at a speed of 800-1000 r / min for 5 min-10 min to obtain polyimide foaming slurry; by mass, the composition of polyimide foaming slurry is: 8 parts water, 90 parts binder, 8 parts thermoplastic expandable microsphere foaming powder, 8 parts crosslinking agent and 20 parts mixture.

[0071] The adhesive is a water-based polyurethane resin adhesive, Anhui Anda Huatai AH-1619, with a solid content of 58±1%, viscosity ≥100 mPa.s, pH value 6-9, and specific gravity 1.06±0.02 g / cm³. 3 .

[0072] The crosslinking agent is an aqueous blocked aliphatic polyisocyanate crosslinking agent, Covestro Imprafix 2794, with a solid content of 11.5±0.5%, viscosity <100 mPa.s, and pH value of 6.5-8.5.

[0073] The foaming powder is a thermoplastic expandable microsphere foaming powder, a dry microsphere, AkzoNobel Expansionl 461WE 40d36, which has a core-shell structure. The outer shell is a thermoplastic acrylic resin polymer, and the core is a hollow spherical microparticle composed of alkane gas. It expands when heated and can reach an average particle size of 40μm.

[0074] (2) Printing

[0075] The polyimide foaming paste is coated onto woven fabric by screen printing, dried, and then baked to obtain polyimide foam printing material.

[0076] Clothing fabric material: Spring woven plain weave fabric (100% polyester), weight 90g / m² 2 ;

[0077] The screen printing mesh has a 100-mesh aperture; the application rate of the printing foaming paste is 10 g / m². 2 ~12g / m 2 ;

[0078] The drying temperature is 70℃~80℃; the drying time is 3~4 minutes;

[0079] The baking temperature is 130℃~140℃;

[0080] The printed pattern is a dense dot pattern, such as... Figure 3 As shown.

[0081] (3) Embossing

[0082] The printed fabric obtained above is processed through a three-dimensional embossing device to prepare an embossed material with a three-dimensional concave-convex structure according to a specific floral pattern.

[0083] The temperature of the three-dimensional embossing roller in the embossing process is 00℃, the pressure is 4.0 MPa, and the embossing speed is 1.5 m / min.

[0084] The three-dimensional embossed pattern is a uniform array of elliptical shapes, with a depth of approximately 1 mm. Figure 4 As shown.

[0085] The printed and embossed fabrics obtained in the examples, as well as the corresponding blank fabric samples, were tested for their warmth retention properties. The results are as follows:

[0086] Table 1. Test results of the thermal insulation performance of fabric samples

[0087]

[0088] Note: The test methods used for Clo value, insulation rate and thermal resistance are GB / T 35762-2017.

[0089] As can be seen from the above embodiments, the present invention first prepares a polyimide foaming slurry containing PI powder, thermoplastic expandable microsphere foaming powder, adhesive, and other components; then, one surface of the garment fabric is coated with this foaming slurry to obtain a polyimide-containing foamed printed fabric; next, the surface of the printed coating of the foamed printed fabric is subjected to three-dimensional embossing to form a textured structure of a certain depth, resulting in a thermal clothing material. The thermal clothing material obtained by the present invention has a foamed printed layer of a certain thickness on its surface, in which polyimide is added, which can reduce the heat conduction of the thermal clothing material. At the same time, the foamed print contains many cavities, which helps to lock in air, reduce heat conduction, and improve the thermal insulation performance of the clothing material. Furthermore, the obtained foamed printed semi-finished material is subjected to three-dimensional embossing to form a textured structure of a certain depth, which can further increase the air content inside the garment and improve the overall thermal insulation performance of the material. The textile fabric obtained by the present invention has excellent heat-locking and thermal insulation performance, thereby significantly improving the thermal insulation experience of the wearer.

[0090] Finally, it should be noted that the specific embodiments described herein are merely illustrative of the spirit of the invention and are not intended to limit the implementation of the invention. Those skilled in the art can make other modifications or additions to the described embodiments and use similar methods to substitute them; it is neither necessary nor possible to exemplify all embodiments here. However, these obvious variations or modifications derived from the essential spirit of the invention still fall within the scope of protection of the invention, and interpreting them as any additional limitation would contradict the spirit of the invention.

Claims

1. A method for preparing a thermal clothing material, characterized in that, Includes the following steps: The polyimide powder was dissolved in an organic solvent to obtain a mixture; the organic solvent was dimethylacetamide and / or dimethylformamide. According to the mass ratio, 5-20 parts of the mixture, 5-10 parts of foaming powder, 90-100 parts of binder, 5-10 parts of crosslinking agent, and water are mixed and stirred to obtain a foaming slurry; the foaming powder is a thermoplastic expandable microsphere foaming powder; the polyimide powder has a mass content of 5%-10% in the foaming slurry, and the average particle size of the polyimide powder is 1-10 μm; the binder is a water-based polyurethane binder; and the crosslinking agent is a water-based blocked aliphatic polyisocyanate crosslinking agent. The foaming paste is applied to one surface of a garment fabric by printing or coating, and then baked at a high temperature to obtain a foamed printed fabric; the high temperature baking temperature is 80~150℃. The printed coating surface of the foamed printed fabric is formed into a concave-convex structure of a certain depth through three-dimensional embossing to obtain a thermal clothing material; the three-dimensional embossing is carried out by a three-dimensional embossing roller at a temperature of 180~200℃, and the pattern of the three-dimensional embossing roller is a uniform closed graphic array with a three-dimensional depth of 1~2mm.

2. The method for preparing the thermal clothing material according to claim 1, characterized in that, The printing method specifically involves: applying the foaming paste to one surface of the garment fabric using a screen printing plate; drying and then baking at high temperature to obtain the foamed printed fabric.

3. The method for preparing the thermal clothing material according to claim 2, characterized in that, The screen printing plate has a mesh size of 100-200 mesh; the main component of the garment fabric is chemical fiber, with a weight of 30-100 g / m². 2 .

4. The method for preparing the thermal clothing material according to claim 3, characterized in that, The pressure for the three-dimensional embossing process is 2.5~4.0MPa.

5. A thermal clothing material, characterized in that, Obtained by the preparation method according to any one of claims 1-4, and used as clothing lining.

Images