Thermal insulation and heat-retaining fleece and its preparation method

Abstract

This invention relates to the field of functional textile materials technology, specifically to a warm and heat-retaining fleece and its preparation method. The method includes the following steps: S1, Blending and spinning: a. Surface layer preparation: Using a fiber ratio of 50-70% cross-section polyester fiber, 5-10% nano-silver thread fiber, 10-20% far-infrared polyester masterbatch, 10-18% nylon staple fiber, 1-4% antistatic agent, and 0.5-1.6% wool oil agent, the raw materials are fed into a twin-screw extruder for melt blending, spun through a cross-shaped spinneret, and then thermally stretched to form a cross-section yarn. This yarn is then knitted using a jacquard process to form a regular pile distribution, resulting in a pre-treated surface layer. This invention utilizes the synergistic effect of nano-silver threads and the antistatic agent to form a conductive network, resulting in an antistatic effect that withstands 50 washes, reduced static voltage, and decreased dust adsorption. Through the blending of silkworm pupa protein viscose, modal, and cashmere, combined with hydrophilic finishing, the moisture absorption is increased many times over, reducing the skin friction factor and eliminating itching, making it suitable for sensitive skin.

Description

Technical Field

[0001] This invention relates to the field of functional textile materials technology, specifically to thermal insulation and heat-retaining fleece and its preparation method. Background Technology

[0002] Heat-retaining fleece is a type of fabric that achieves its heat-retaining effect through a special processing technique that creates a fleece-like texture on its surface. It is typically made of polyester fiber (commonly known as "polyester"), and some may incorporate other materials such as cashmere. Fleece, also called pineapple fleece, is characterized by its strong three-dimensional effect, high weight, and thick fabric.

[0003] Currently, quince, as a high-grammage fleece fabric, is widely used in home textiles and apparel, but its traditional manufacturing process has the following shortcomings:

[0004] Static electricity problem: Synthetic fibers such as polyester are prone to generating static electricity due to friction, which causes the fabric to attract dust and stick to the skin, affecting wearing comfort.

[0005] Insufficient skin affinity: Traditional polyester fibers have a smooth surface and poor moisture absorption, which can easily cause itching when in direct contact with the skin, especially for infants or people with sensitive skin.

[0006] Hair removal and pilling: The down structure has poor stability and is prone to hair removal after long-term friction or washing. In addition, the fibers and hairs become entangled and form hair balls, which reduces the product's lifespan.

[0007] While existing technologies improve some properties by blending natural fibers or surface finishing, they do not systematically solve the aforementioned multi-dimensional problems. Furthermore, the antistatic effect is not durable enough, the skin-friendly effect is only slightly improved, and hair removal is still quite noticeable. Summary of the Invention

[0008] The purpose of this invention is to provide a warm and heat-retaining fleece and its preparation method, which has the advantages of long-lasting antistatic properties, extreme skin-friendliness and strong anti-hair loss performance, solving the core pain points of traditional fleece while maintaining its excellent warm and heat-retaining performance.

[0009] To achieve the above objectives, the present invention provides the following technical solution: a method for preparing heat-retaining and heat-storing fleece, the method comprising the following steps:

[0010] S1, Blended fabrics and spinning:

[0011] a. Surface layer preparation: The fiber ratio of 50-70% cross-section polyester fiber, 5-10% nano silver thread fiber, 10-20% far-infrared polyester masterbatch, 10-18% nylon staple fiber, 1-4% antistatic agent, and 0.5-1.6% oiling agent is used. The raw materials are fed into a twin-screw extruder, melt-blended, spun through a cross-shaped spinneret, and then hot-stretched to form a cross-section yarn. The yarn is then knitted using a jacquard knitting process to form a regular pile distribution, thus obtaining the pretreated surface layer.

[0012] b. Preparation of the bottom layer: The fiber ratio of 15-25% silkworm pupa protein viscose, 35-45% modal, 20-30% cashmere, 3-5% spandex core-spun yarn, and 5-8% fine denier nylon is used to blend the yarn into yarn through Siro compact spinning process. A high-density knitting structure is used to form a tightly closed down base to obtain the pretreated bottom layer.

[0013] S2, Double-layer weaving: PUR hot melt adhesive is applied to the bottom surface by a hot melt adhesive spot bonding machine, and the pile layer is combined with the base fabric layer by a four-track knitting machine to obtain the pre-treated warm and heat-retaining fleece fabric.

[0014] S3. Pre-treatment: float training, pre-shaping and singeing;

[0015] S4. Staining: Select acid dyes and disperse dyes in the same bath, and use reactive dyes for step-by-step staining;

[0016] S5. Finishing: napping, finishing solution treatment, and final shaping.

[0017] Preferably, in step a, the twin-screw extruder operates at a temperature of 280-290℃ and a melt pressure of 8-10MPa, while the cross-shaped spinneret has 48F holes with a diameter of 0.3mm×0.8mm. At the same time, the hot stretching ratio is controlled at 3.0-3.5 times to ensure a hollowness of 30%-35% in the cross-shaped cross section yarn.

[0018] Preferably, the parameters of the hot melt adhesive in step S2 are: model: PUR GT-5015B, adhesive dot diameter: 1.5mm, spacing: 4mm, coating temperature: 135-145℃, pressure: 0.5kgf / cm². 2 Adhesive dosage control: 2-3g / m 2 .

[0019] Preferably, in step S3, the bleaching process involves mixing the fabric and water at a ratio of 1:10, adding 0.5% soda ash and 30% hydrogen peroxide sequentially, raising the temperature to 75°C at a rate of 2°C / min, maintaining the temperature for 30 minutes, washing twice with 90°C hot water for 5 minutes each time, and finally washing with cold water until neutral.

[0020] Preferably, in step S3, the pre-forming process uses a pin plate tenter frame with a temperature of 185°C, a speed of 28m / min, and an overfeed of 5% to stabilize the fabric size. The singeing process uses a double-sided gas singeing machine with a flame temperature of 800°C, a conveyor speed of 100m / min, and 3 singeing levels to remove surface fuzz and impurities.

[0021] Preferably, in step S4, when the acid dye and disperse dye are bathed together, the bath ratio is 1:10. The initial pH is adjusted to 4.8 with glacial acetic acid, the temperature is increased at a rate of 1.5℃ / min to 130℃, and the temperature is maintained for 60 min. This is used for dyeing polyester and far-infrared polyester with disperse dye. The temperature is then lowered to 90℃, formic acid is added to adjust the pH to 4.0, and the temperature is maintained for 30 min. This is used for fixing cashmere and silkworm pupa protein viscose with acid dye. The reactive dye used is Reactive Yellow KE-4R 1% owf, sodium sulfate 50 g / L, soda ash 20 g / L, and the temperature is maintained at 60℃ for 60 min. This is used for dyeing modal.

[0022] Preferably, in step S5, the raising and combing are performed using a three-stage raising machine. Initial raising: rotation speed 300 r / min, card cloth density 20 needles / cm, forming 0.5mm short pile. Fine raising: rotation speed 400 r / min, replacing with fine card cloth of 30 needles / cm, increasing the pile height to 1.2mm. Combing: metal card cloth combing in the opposite direction, speed ratio 1:1.2, so that the pile is oriented and the lying angle is ≤30°.

[0023] Preferably, the weight percentage of the finishing solution formulation in step S5 is: 4-8% far-infrared ceramic powder, 6-12% hydrophilic silicone emulsion, 5-8% composite antistatic agent, 3-6% waterborne polyurethane crosslinking agent, 2-3% chitosan colloid, and the balance is deionized water. The finishing process of the finishing solution is as follows: two dips and two nips: 68% nips, 45℃ dip temperature, and 0.8MPa pressure; pre-drying: 80℃ hot air circulation for 10 minutes until the moisture content drops to 30%; baking: using a chain baking machine, speed 15m / min, temperature 145-165℃, and time 4 minutes.

[0024] Preferably, in step S5, the finished product setting temperature is 175℃, the machine speed is 22m / min, the overfeed is 3%, and the setting time is 30s.

[0025] The heat-retaining and heat-absorbing fleece is prepared using the same method as the heat-retaining and heat-absorbing fleece.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0027] 1. This invention utilizes the synergistic effect of silver nanowires and antistatic agents to form a conductive network, resulting in an antistatic effect that can withstand 50 washes, reduced static voltage, and decreased dust adsorption.

[0028] 2. This invention uses silkworm pupa protein adhesive, modal and cashmere blends, combined with hydrophilic finishing, to improve moisture absorption many times over, reduce skin friction factor, eliminate itching sensation, and is suitable for sensitive skin.

[0029] 3. This invention utilizes a three-stage napping process involving heating and melting adhesive points on a high-density knitted substrate, which reduces the napping rate, improves the pilling level, and extends the product lifespan.

[0030] 4. This invention improves the heat retention efficiency of traditional fabrics by adding far-infrared masterbatch to the hollow fiber with a cross-shaped cross section, and has the dual effects of heat storage and heat insulation.

[0031] 5. This invention shortens the process by using the same bath for dyeing, saves water, reduces the amount of adhesive used by hot melt adhesive spot bonding, reduces VOC emissions, and reduces production energy consumption. Detailed Implementation

[0032] Example 1

[0033] This invention provides a technical solution: thermal insulation and heat-retaining fleece and its preparation method, comprising the following steps:

[0034] S1, Blended fabrics and spinning:

[0035] a. Surface layer preparation: The fiber ratio is 50% cross-section polyester fiber, 10% nano silver fiber, 20% far-infrared polyester masterbatch, 18% nylon staple fiber, 1% antistatic agent, and 1% oiling agent. The raw materials are fed into a twin-screw extruder for melt blending, spun through a cross-shaped spinneret, and then hot-stretched to form a cross-section yarn. The yarn is then knitted using a jacquard knitting process to form a regular pile distribution, resulting in a pre-treated surface layer. The twin-screw extruder operates at a temperature of 280℃ and a melt pressure of 8MPa. The cross-shaped spinneret has 48F holes with a diameter of 0.3mm × 0.8mm. At the same time, the hot stretching ratio is controlled at 3.0 times to ensure a 30% hollowness of the cross-section yarn.

[0036] b. Preparation of the bottom layer: The fiber ratio of 15% silkworm pupa protein viscose, 35% modal, 20% cashmere, 3% spandex core-spun yarn and 5% fine denier nylon is used to blend the yarn into yarn through Siro compact spinning process, and a high-density knitted structure is used to form a tightly closed down base to obtain the pretreated bottom layer.

[0037] S2. Double-layer weaving: PUR hot melt adhesive is applied to the bottom layer surface using a hot melt adhesive dotting machine. A four-track knitting machine is then used to bond the fleece layer to the base fabric layer, resulting in a pre-treated, warm and heat-retaining fleece fabric. The hot melt adhesive parameters are: Model: PUR GT-5015B, Dot diameter: 1.5mm, Spacing: 4mm, Coating temperature: 135-145℃, Pressure: 0.5kgf / cm². 2 Adhesive dosage control: 2-3g / m 2 ;

[0038] S3. Pretreatment: scouring, bleaching, pre-setting, and singeing. Scouring involves mixing the fabric and water at a 1:10 liquor ratio, adding 0.5% soda ash and 30% hydrogen peroxide sequentially, raising the temperature to 75°C at a rate of 2°C / min, holding for 30 minutes, washing twice in 90°C hot water for 5 minutes each time, and washing with cold water until neutral. Pre-setting uses a tenter frame at 185°C, a speed of 28m / min, and an overfeed of 5% to stabilize the fabric dimensions. Singeing uses a double-sided gas singeing machine at 800°C, a conveyor speed of 100m / min, and 3 singeing levels to remove surface fuzz and impurities.

[0039] S4. Dyeing: Select acid dyes and disperse dyes in the same bath, and use reactive dyes for step-by-step dyeing. When acid dyes and disperse dyes are in the same bath, the bath ratio is 1:10. Adjust the initial pH to 4.8 with glacial acetic acid, raise the temperature at a rate of 1.5℃ / min to 130℃, and hold for 60 min. This is used for dyeing polyester and far-infrared polyester with disperse dyes. Cool down to 90℃, add formic acid to adjust the pH to 4.0, and hold for 30 min. This is used for fixing cashmere and silkworm pupa protein viscose with acid dyes. For reactive dyes, use Reactive Yellow KE-4R 1% owf, sodium sulfate 50g / L, soda ash 20g / L, and hold at 60℃ for 60 min. This is used for dyeing modal. For acid dyes, use Weak Acid Red GN (2% owf) with a pH of 4.5. For disperse dyes, use Disperse Blue 2BLN (1.5% owf) with a carrier (o-phenylphenol) of 1%.

[0040] S5. Finishing: Raising, finishing solution treatment, and final shaping. Raising and combing use a three-stage raising machine. Initial raising: speed 300r / min, card cloth density 20 needles / cm, forming 0.5mm short pile. Fine raising: speed 400r / min, changing to 30 needles / cm fine card cloth, increasing the pile height to 1.2mm. Combing: metal card cloth reverse combing, speed ratio 1:1.2, to orient the pile, with a flattening angle ≤30°. The finishing solution formula has the following weight percentages: 4% far-infrared ceramic powder, 6% hydrophilic organic... The finishing solution consists of silicone emulsion, 5% composite antistatic agent, 3% waterborne polyurethane crosslinking agent, 2% chitosan colloid, and the balance is deionized water. The finishing process is as follows: two dips and two nips: 68% nips, 45℃ dip temperature, and 0.8MPa pressure; pre-drying: 80℃ hot air circulation for 10 minutes, reducing the moisture content to 30%; baking: using a chain baking machine, speed 15m / min, temperature 145-165℃, time 4 minutes; finished product setting temperature 175℃, speed 22m / min, overfeed 3%, and setting time 30s.

[0041] This technical solution incorporates nano-silver fibers (conductive nanomaterials) and an antistatic agent, forming a dual mechanism of "conductive network plus surface antistatic," resulting in significantly superior antistatic durability compared to traditional single-agent additions. Furthermore, the cross-shaped cross-section polyester fibers, through their hollow structure (controlled by thermal stretching ratio), reduce the frictional area between fibers, lowering the probability of static electricity generation at its source. The cross-shaped cross-section yarns, through a regular pile distribution (jacquard knitting process), form an air insulation layer, increasing hollowness and improving warmth retention compared to traditional fabrics. Additionally, the far-infrared polyester masterbatch absorbs radiant heat from the human body and reflects it back to the skin, creating a dual warmth retention system of "heat storage plus insulation" combined with the hollow structure. Simultaneously, the cross-shaped spinneret spins... The fibers have sharp, angular cross-sections, enhanced inter-fiber cohesion, and reduced exposed fuzz. After heat stretching, the fiber strength is improved, and its abrasion resistance is superior to traditional round fibers. The bottom layer is made of blended silkworm pupa protein viscose (containing amino acid groups, with skin-friendly properties similar to silk) and modal (natural wood pulp fiber, with 1.5 times the moisture absorption of cotton), which improves the surface smoothness and reduces skin friction irritation. The addition of cashmere fibers makes the bottom layer soft to the touch, and combined with the elasticity of spandex core-spun yarn, it improves the stiffness of traditional fabrics, making it more suitable for infants' skin. The Siro compact spinning process reduces yarn fuzz, and the high-density knitting structure (finer needle spacing) forms a "down-locking base," which improves the down-fixing strength compared to traditional plain knitting.

[0042] Double-layer weave, using PUR GT-5015B hot melt adhesive for dot bonding (dot diameter 1.5mm, spacing 4mm, adhesive amount 2-3g / m²). 2 By replacing "surface contact" with "point contact", the bonding strength reaches 80% of the traditional method, while the air permeability is increased by 60%, avoiding the problem of skin irritation caused by the adhesive layer. The four-track knitting machine composite process makes the pile layer and the base fabric layer more evenly bonded, reducing the phenomenon of local delamination or adhesive residue in the traditional process.

[0043] Pre-treatment and bleaching processes precisely control the heating rate (2℃ / min to 75℃) and holding time, combined with optimized hydrogen peroxide concentration, to remove fiber impurities while reducing strength damage; pre-forming uses a pin plate tenter frame (temperature 185℃, overfeed 5%), controlling the shrinkage rate to ≤2%, which is superior to traditional processes; double-sided gas singeing (flame temperature 800℃, level 3 singeing) thoroughly removes surface fuzz, improving the smoothness of the fabric surface, and making the pile arrangement more regular during subsequent napping, reducing the risk of pilling;

[0044] The dyeing process uses acid dyes and disperse dyes in the same bath. By taking advantage of the temperature difference between the dyeing of polyester fibers and cashmere / silkworm pupa protein, the dyeing of synthetic fibers and protein fibers is completed in one step, reducing the number of steps by 40% and saving water by 30%. The step-by-step dyeing with reactive dyes, combined with formic acid to adjust the pH value, improves the color fastness of natural fibers such as cashmere and modal by 1-2 grades, reaching grade 4 or above.

[0045] The finishing process involves precise control of the pile structure, significantly enhancing anti-pilling and anti-shedding capabilities. A three-stage napping machine precisely controls the pile height and angle, ensuring neat and oriented pile arrangement that prevents tangling during friction, achieving a pilling level of 4. The metal needle cloth reverse combing tightens the pile roots, and combined with the high-density underlying structure, reduces the shedding rate by 60% compared to traditional napping processes. Furthermore, the finishing solution in this method combines far-infrared ceramic powder (reflecting human body heat) with hydrophilic silicone emulsion, enhancing warmth retention and forming a hydrophilic film on the fiber surface, improving moisture absorption and alleviating the dryness of traditional polyester fibers. A composite antistatic agent (cationic and non-ionic) and a water-based polyurethane crosslinking agent form a mesh coating layer, providing antistatic protection against 50 washes while strengthening inter-fiber bonding and reducing shedding. This method, through material innovation, structural optimization, and process synergy, achieves a systematic breakthrough overcoming the defects of traditional polyester fabrics, with significant advantages in long-lasting antistatic properties, skin-friendly comfort, and durability.

[0046] Example 2

[0047] Based on Example 1, the present invention provides a thermal insulation and heat-retaining fleece and its preparation method, comprising the following steps:

[0048] S1, Blended fabrics and spinning:

[0049] a. Surface layer preparation: The fiber ratio of 70% cross-section polyester fiber, 5% nano-silver fiber, 10% far-infrared polyester masterbatch, 10% nylon staple fiber, 3.4% antistatic agent, and 1.6% oiling agent is used. The raw materials are fed into a twin-screw extruder for melt blending, spun through a cross-shaped spinneret, and then hot-stretched to form a cross-section yarn. The yarn is then knitted using a jacquard knitting process to form a regular pile distribution, resulting in a pre-treated surface layer. The working temperature of the twin-screw extruder is 290℃ and the melt pressure is 10MPa. The cross-shaped spinneret has 48F holes with a diameter of 0.3mm × 0.8mm. At the same time, the hot stretching ratio is controlled at 3.5 times to ensure a 35% hollowness of the cross-section yarn.

[0050] b. Preparation of the bottom layer: The fiber ratio of 25% silkworm pupa protein viscose, 45% modal, 30% cashmere, 5% spandex core-spun yarn and 8% fine denier nylon is used to blend the yarn into yarn through Siro compact spinning process, and a high-density knitted structure is used to form a tightly locked down base to obtain the pretreated bottom layer.

[0051] S2. Double-layer weaving: PUR hot melt adhesive is applied to the bottom layer surface using a hot melt adhesive dotting machine. A four-track knitting machine is then used to bond the fleece layer to the base fabric layer, resulting in a pre-treated, warm and heat-retaining fleece fabric. The hot melt adhesive parameters are: Model: PUR GT-5015B, Dot diameter: 1.5mm, Spacing: 4mm, Coating temperature: 145℃, Pressure: 0.5kgf / cm². 2 Adhesive dosage control: 3g / m2 ;

[0052] S3. Pretreatment: scouring, bleaching, pre-setting, and singeing. Scouring involves mixing the fabric and water at a 1:10 liquor ratio, adding 0.5% soda ash and 30% hydrogen peroxide sequentially, raising the temperature to 75°C at a rate of 2°C / min, holding for 30 minutes, washing twice in 90°C hot water for 5 minutes each time, and washing with cold water until neutral. Pre-setting uses a tenter frame at 185°C, a speed of 28m / min, and an overfeed of 5% to stabilize the fabric dimensions. Singeing uses a double-sided gas singeing machine at 800°C, a conveyor speed of 100m / min, and 3 singeing levels to remove surface fuzz and impurities.

[0053] S4. Dyeing: Select acid dyes and disperse dyes in the same bath, and use reactive dyes for step-by-step dyeing. When acid dyes and disperse dyes are in the same bath, the bath ratio is 1:10. Adjust the initial pH to 4.8 with glacial acetic acid, raise the temperature at a rate of 1.5℃ / min to 130℃, and hold for 60 min. This is used for dyeing polyester and far-infrared polyester with disperse dyes. Cool down to 90℃, add formic acid to adjust the pH to 4.0, and hold for 30 min. This is used for fixing cashmere and silkworm pupa protein viscose with acid dyes. For reactive dyes, use Reactive Yellow KE-4R 1% owf, sodium sulfate 50g / L, soda ash 20g / L, and hold at 60℃ for 60 min. This is used for dyeing modal. For acid dyes, use Weak Acid Red GN (2% owf) with a pH of 5.0. For disperse dyes, use Disperse Blue 2BLN (1.5% owf) with 1% carrier (o-phenylphenol).

[0054] S5. Finishing: Raising, finishing solution treatment, and final shaping. Raising and combing use a three-stage raising machine. Initial raising: speed 300r / min, card cloth density 20 needles / cm, forming 0.5mm short pile. Fine raising: speed 400r / min, changing to 30 needles / cm fine card cloth, increasing the pile height to 1.2mm. Combing: metal card cloth reverse combing, speed ratio 1:1.2, to orient the pile, with a flattening angle ≤30°. The finishing solution formula has the following weight percentages: 8% far-infrared ceramic powder, 12% hydrophilic organic... The finishing solution consists of silicone emulsion, 8% composite antistatic agent, 6% waterborne polyurethane crosslinking agent, 3% chitosan colloid, and the balance is deionized water. The finishing process is as follows: two dips and two nips: 68% nips, 45℃ dip temperature, and 0.8MPa pressure; pre-drying: 80℃ hot air circulation for 10 minutes, reducing the moisture content to 30%; baking: using a chain baking machine, speed 15m / min, temperature 145-165℃, time 4 minutes; finished product setting temperature 175℃, speed 22m / min, overfeed 3%, and setting time 30s.

[0055] Example 3

[0056] Based on Example 1, the present invention provides a thermal insulation and heat-retaining fleece and its preparation method, comprising the following steps:

[0057] S1, Blended fabrics and spinning:

[0058] a. Surface layer preparation: The fiber ratio of 60% cross-section polyester fiber, 8% nano-silver fiber, 17% far-infrared polyester masterbatch, 13% nylon staple fiber, 1.2% antistatic agent, and 0.8% oiling agent is used. The raw materials are fed into a twin-screw extruder for melt blending, spun through a cross-shaped spinneret, and then hot-stretched to form a cross-section yarn. The yarn is then knitted using a jacquard knitting process to form a regular pile distribution, resulting in a pre-treated surface layer. The working temperature of the twin-screw extruder is 285℃ and the melt pressure is 9MPa. The cross-shaped spinneret has 48F holes with a diameter of 0.3mm × 0.8mm. At the same time, the hot stretching ratio is controlled at 3.3 times to ensure a hollowness of 33% in the cross-section yarn.

[0059] b. Preparation of the bottom layer: The fiber ratio of 20% silkworm pupa protein viscose, 40% modal, 25% cashmere, 4% spandex core-spun yarn and 6.5% fine denier nylon is used to blend the yarn into yarn through Siro compact spinning process, and a high-density knitting structure is used to form a tightly closed down base to obtain the pretreated bottom layer.

[0060] S2. Double-layer weaving: PUR hot melt adhesive is applied to the bottom layer surface using a hot melt adhesive dotting machine. A four-track knitting machine is then used to bond the fleece layer to the base fabric layer, resulting in a pre-treated, warm and heat-retaining fleece fabric. The hot melt adhesive parameters are: Model: PUR GT-5015B, Dot diameter: 1.5mm, Spacing: 4mm, Coating temperature: 140℃, Pressure: 0.5kgf / cm². 2 Adhesive dosage control: 2.5g / m 2 ;

[0061] S3. Pretreatment: scouring, bleaching, pre-setting, and singeing. Scouring involves mixing the fabric and water at a 1:10 liquor ratio, adding 0.5% soda ash and 30% hydrogen peroxide sequentially, raising the temperature to 75°C at a rate of 2°C / min, holding for 30 minutes, washing twice in 90°C hot water for 5 minutes each time, and washing with cold water until neutral. Pre-setting uses a tenter frame at 185°C, a speed of 28m / min, and an overfeed of 5% to stabilize the fabric dimensions. Singeing uses a double-sided gas singeing machine at 800°C, a conveyor speed of 100m / min, and 3 singeing levels to remove surface fuzz and impurities.

[0062] S4. Dyeing: Select acid dyes and disperse dyes in the same bath, and use reactive dyes for step-by-step dyeing. When acid dyes and disperse dyes are in the same bath, the bath ratio is 1:10. Adjust the initial pH to 4.8 with glacial acetic acid, raise the temperature at a rate of 1.5℃ / min to 130℃, and hold for 60 min. This is used for dyeing polyester and far-infrared polyester with disperse dyes. Cool down to 90℃, add formic acid to adjust the pH to 4.0, and hold for 30 min. This is used for fixing cashmere and silkworm pupa protein viscose with acid dyes. For reactive dyes, use Reactive Yellow KE-4R 1% owf, sodium sulfate 50g / L, soda ash 20g / L, and hold at 60℃ for 60 min. This is used for dyeing modal. For acid dyes, use Weak Acid Red GN (2% owf) with a pH of 4.8. For disperse dyes, use Disperse Blue 2BLN (1.5% owf) with 1% carrier (o-phenylphenol).

[0063] S5. Finishing: Raising, finishing solution treatment, and final shaping. Raising and combing use a three-stage raising machine. Initial raising: speed 300r / min, card cloth density 20 needles / cm, forming 0.5mm short pile. Fine raising: speed 400r / min, changing to 30 needles / cm fine card cloth, increasing the pile height to 1.2mm. Combing: metal card cloth reverse combing, speed ratio 1:1.2, to orient the pile, with a flattening angle ≤30°. The finishing solution formula has the following weight percentages: 6% far-infrared ceramic powder, 9% hydrophilic organic... The product consists of silicone emulsion, 6.5% composite antistatic agent, 5% waterborne polyurethane crosslinking agent, 2.5% chitosan colloid, and the balance being deionized water. The finishing process is as follows: two dips and two nips: 68% nips, 45℃ dip temperature, and 0.8MPa pressure; pre-drying: 80℃ hot air circulation for 10 minutes to reduce the moisture content to 30%; baking: using a chain baking machine, speed 15m / min, temperature 155℃, time 4 minutes; final setting temperature 175℃, speed 22m / min, overfeed 3%, and setting time 30s.

[0064] Comparative Example 1

[0065] Compared with Example 1, the difference in Comparative Example 1 is that the cross-shaped cross section yarn is not used in step S1, and traditional polyester fiber is used as the main material. Specifically, "a. Surface preparation: Polyester fiber yarn is used to form a regular pile distribution through jacquard knitting process to obtain a pre-treated surface layer". The other steps remain unchanged, and the prepared heat-insulating and heat-retaining fleece is referred to as Comparative Example 1.

[0066] Comparative Example 2

[0067] Compared with Example 1, the difference in Comparative Example 2 is that in step S2, PUR hot melt adhesive is not applied to the bottom surface through a hot melt adhesive dotting machine. Instead, the traditional hot melt adhesive surface coating method is mainly used. Specifically, "S2, double-layer weaving: PUR hot melt adhesive is applied to the bottom surface through hot melt adhesive coating. The pile layer and the base fabric layer are combined using a four-track knitting machine to obtain the pretreated thermal insulation and heat storage fleece fabric." The other steps remain unchanged, and the prepared thermal insulation and heat storage fleece is referred to as Comparative Example 2.

[0068] Comparative Example 3

[0069] Compared with Example 1, the difference in Comparative Example 3 is that in step S4, acid dye and disperse dye are not used in the same bath, and reactive dye is used for step-by-step dyeing. Specifically, "S4, dyeing: dyeing in the dyeing pool" is used. The other steps remain unchanged. The prepared heat-retaining and heat-storing baby fleece is referred to as Comparative Example 3.

[0070] Performance testing experiments: The thermal insulation and heat-retaining fleece fabric prepared by the traditional method was compared with the thermal insulation and heat-retaining fleece fabrics prepared in Examples 1-3 and Comparative Examples 1-3 in the following experiments. The experimental contents and results are shown in the table below.

[0071]

[0072]

[0073] As can be seen from the table, the experiments show that the thermal insulation fleece prepared in Examples 1, 2, and 3 is better than the thermal insulation fleece fabrics prepared in Comparative Examples 1, 2, and 3 in terms of surface resistivity, lint removal rate, pilling level, far-infrared emissivity, and skin-friendliness. At the same time, the thermal insulation fleece prepared in Examples 1, 2, and 3 has a significant improvement in performance compared with the thermal insulation fleece fabric prepared by the traditional method in terms of surface resistivity, lint removal rate, pilling level, far-infrared emissivity, and skin-friendliness.

[0074] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit the scope of protection of the present invention. 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 essence and scope of the technical solutions of the present invention.

Claims

1. A method for preparing heat-retaining and heat-storing fleece, characterized in that, The method includes the following steps: S1, Blended fabrics and spinning: a. Surface layer preparation: The fiber ratio is 50-70% cross-section polyester fiber, 5-10% nano silver thread fiber, 10-20% far-infrared polyester masterbatch, 10-18% nylon staple fiber, 1-4% antistatic agent, and 0.5-1.6% hair oil agent. The raw materials are fed into a twin-screw extruder, melt-blended, spun through a cross-shaped spinneret, and then hot-stretched to form a cross-section yarn. The yarn is then knitted using a jacquard knitting process to form a regular pile distribution, thus obtaining the pretreated surface layer. b. Preparation of the bottom layer: The fiber ratio of 15-25% silkworm pupa protein viscose, 35-45% modal, 20-30% cashmere, 3-5% spandex core-spun yarn, and 5-8% fine denier nylon is used to blend the yarn through Siro compact spinning process. A high-density knitting structure is used to form a tightly closed down base to obtain the pre-treated bottom layer. S2, Double-layer weaving: PUR hot melt adhesive is applied to the bottom surface by a hot melt adhesive spot bonding machine, and the fleece layer is combined with the base fabric layer by a four-track knitting machine to obtain the pre-treated warm and heat-retaining fleece fabric. S3. Pre-treatment: Float training, pre-shaping and singeing; S4. Staining: Select acid dyes and disperse dyes in the same bath, and use reactive dyes for step-by-step staining; S5. Finishing: napping, finishing solution treatment, and final shaping; In step a, the twin-screw extruder operates at a temperature of 280-290℃ and a melt pressure of 8-10MPa. The cross-shaped spinneret has 48F holes with a diameter of 0.3mm × 0.8mm. Meanwhile, the hot stretching ratio is controlled at 3.0-3.5 times to ensure a hollowness of 30%-35% in the cross-shaped cross section yarn. The parameters of the hot melt adhesive in step S2 are as follows: model: PUR GT-5015B, adhesive dot diameter: 1.5mm, spacing: 4mm, coating temperature: 135-145℃, pressure: 0.5kgf / cm², adhesive amount control: 2-3g / m². In step S3, the fabric and water are mixed at a ratio of 1:10, and 0.5% soda ash and 30% hydrogen peroxide are added in sequence. The temperature is raised to 75°C at a rate of 2°C / min, kept warm for 30 minutes, washed twice in 90°C hot water for 5 minutes each time, and then washed in cold water until neutral. In step S3, the pre-forming process uses a pin plate tenter frame with a temperature of 185℃, a speed of 28m / min, and an overfeed of 5% to stabilize the fabric size. The singeing process uses a double-sided gas singeing machine with a flame temperature of 800℃, a conveyor speed of 100m / min, and 3 singeing levels to remove surface fuzz and impurities. In step S4, when acid dye and disperse dye are bathed together, the bath ratio is 1:

10. The initial pH is adjusted to 4.8 with glacial acetic acid, the temperature is increased at a rate of 1.5℃ / min to 130℃, and the temperature is maintained for 60 min. This is used for dyeing polyester and far-infrared polyester with disperse dye. The temperature is then lowered to 90℃, formic acid is added to adjust the pH to 4.0, and the temperature is maintained for 30 min. This is used for fixing cashmere and silkworm pupa protein viscose with acid dye. The reactive dye used is Reactive Yellow KE-4R 1%owf, sodium sulfate 50g / L, soda ash 20g / L, and the temperature is maintained at 60℃ for 60 min. This is used for dyeing modal. In step S5, the raising and combing processes are performed using a three-stage raising machine. Initial raising: rotation speed 300 r / min, card cloth density 20 needles / cm, forming 0.5mm short pile. Fine raising: rotation speed 400 r / min, replacing with fine card cloth of 30 needles / cm, increasing the pile height to 1.2mm. Combing: metal card cloth combing in the reverse direction, speed ratio 1:1.2, to orient the pile so that the folding angle is ≤30°.

2. The method for preparing the heat-retaining and heat-storing fleece according to claim 1, characterized in that: The weight percentage of the finishing solution formulation in step S5 is as follows: 4-8% far-infrared ceramic powder, 6-12% hydrophilic silicone emulsion, 5-8% composite antistatic agent, 3-6% waterborne polyurethane crosslinking agent, 2-3% chitosan colloid, and the balance is deionized water. The finishing process of the finishing solution is as follows: two dips and two nips: 68% nips, 45℃ dip temperature, and 0.8MPa pressure; pre-drying: 80℃ hot air circulation for 10 minutes until the moisture content drops to 30%; baking: using a chain baking machine, speed 15m / min, temperature 145-165℃, and time 4 minutes.

3. The method for preparing the heat-retaining and heat-storing fleece according to claim 1, characterized in that: In step S5, the finished product setting temperature is 175℃, the machine speed is 22m / min, the overfeed is 3%, and the setting time is 30s.

4. A heat-retaining and heat-absorbing fleece, prepared by the heat-retaining and heat-absorbing fleece preparation method of any one of claims 1-3.

Images