Preparation method of cool composite fabric

Abstract

The application relates to a preparation method of a cool composite fabric, and relates to the field of knitting. Cool polylactic acid-polyether ester blended hollow fibers and flax fibers are selected, are gradient blended into yarns after synergistic modification, are knitted into a fabric base layer with a double-needle bed double-sided knitting machine to form a composite structure, cool functional yarns with a core-sheath structure are prepared through concentric composite spinning, and a single-jacquard knitting machine is used to construct a composite layer through variable-distance alternate interweaving. Subsequently, the cool composite fabric is obtained through segmented preshrinking, graded washing, composite functional finishing, multi-section gradient setting and surface micro-nano structuring treatment. Through synergistic raw material modification and functional finishing of the knitting process, the cool composite fabric improves the cool conduction efficiency, structural stability and wearing comfort of the fabric, and is suitable for summer clothing, home textiles and the like.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of knitting, and particularly relates to a preparation method of a cool composite fabric. BACKGROUND

[0002] The cool composite fabric can quickly conduct heat and bring a cool touch when contacting the skin, and is widely used in summer clothing, home textiles and other fields. Knitted fabric, with the characteristics of softness, breathability and close-fitting to the human body, becomes an important carrier of cool function, and the scientificity of its preparation process directly affects the cool durability, structural stability and wearing comfort. At present, the industry often adds cool fibers or applies cool finishing agents to achieve basic cool effect, but there are still obvious deficiencies in raw material adaptation and function synergy.

[0003] In the prior art, single treatment is often used for raw material modification, and the synergy optimization of cool fibers and carrier fibers cannot be achieved, resulting in poor fiber compatibility, quality problems in the spinning process, and further affecting the fabric forming effect. At the same time, the knitting forming process of the composite fabric lacks targeted design, and the conventional knitting structure cannot balance the stiffness and elasticity, and the connection between the composite layer and the base layer often uses fixed spacing interweaving, which is prone to delamination or air permeability problems, and cannot achieve the balance between structural stability and high efficiency.

[0004] In addition, the finishing process often focuses on single performance optimization, and the synergy of soft finishing and cool function is insufficient. The surface structure design of the fabric is relatively simple, and the cool conduction efficiency is limited. With the increasing demand of consumers for the functionality and comfort of clothing, there is an urgent need for a preparation method with rigorous process logic to solve the problems of poor fiber compatibility, unstable composite structure, and difficult to balance cool and comfortable performance in the prior art through the whole process optimization of raw material synergy modification, knitting process innovation and finishing function enhancement, and to promote the quality upgrading of cool knitted fabric. SUMMARY

[0005] In order to overcome the above-mentioned defects of the prior art, the embodiments of the present application provide a preparation method of a cool composite fabric, which solves the problems of poor fiber compatibility, unstable composite structure and difficult to balance cool and comfortable performance in the prior art.

[0006] To solve the above problems, the present application provides the following technical solutions:

[0007] A preparation method of a cool composite fabric, comprising the following steps,

[0008] S1. Raw material combination and synergy modification, selecting cool poly-lactic acid-poly-ether ester blended hollow fiber and flax fiber as the basic raw material, treating the cool poly-lactic acid-poly-ether ester blended hollow fiber with argon atmosphere low temperature plasma surface grafting of acrylic acid, and treating the flax fiber with polyethylene glycol-chitosan composite system grafting modification;

[0009] S2. Gradient blending yarn is formed, the two modified fibers are mixed according to the set proportion, and are sequentially subjected to air flow opening, four carding, four-stage drawing, double-zone heating roving drafting, and dynamic twisting and spinning processes to form blended yarn, and four-section online gradient oiling treatment is adopted in the spinning process;

[0010] S3. Double-system temperature-controlled knitted base is formed, a double-needle bed double-sided knitting machine is used for knitting processing, the needle pitch and the frequency conversion yarn feeding speed of the knitting machine are set, the knitting temperature is respectively regulated and controlled through the needle cylinder independent temperature control module and the needle disc independent temperature control module, and a plain weave-double rib-flower composite organization fabric base layer is formed by knitting;

[0011] S4. Cool functional yarn preparation, cool polyester-polyamide blended chips and bamboo pulp viscose fibers are selected, and a cool functional yarn with a core-sheath structure is prepared through a concentric composite spinning process, the core layer is a cool polyester-polyamide blended component, and the sheath layer is a bamboo pulp viscose fiber component, the core layer component is extruded through a central spinning hole, and the sheath layer bamboo pulp viscose fiber is extruded through a peripheral annular spinning hole, a side blowing cooling technology is adopted in the spinning process, the side blowing air pressure is 0.15-0.2 MPa, and the vertical distance between the side blowing device and the spinning hole is 30-40 cm;

[0012] S5. Variable pitch interwoven composite forming, a single-side jacquard knitting machine is used to perform variable pitch interwoven knitting on one side of the fabric base layer, the interwoven frequency is adjusted in a cycle of 1 composite layer coil interwoven for every 3 base layer coils, 1 composite layer coil interwoven for every 4 base layer coils, and 1 composite layer coil interwoven for every 5 base layer coils, so that the cool functional yarn and the fabric base layer are periodically interwoven and connected to form a composite layer, and the needle bed displacement of the knitting machine is adjusted synchronously according to the corresponding rules during the interweaving process, and the needle bed movement frequency and the yarn feeding speed are kept adaptive;

[0013] S6. Sectional preshrinking relaxation treatment, the interwoven composite fabric is subjected to multi-section relaxation preshrinking treatment, the preshrinking temperature is controlled by gradient heating, and the preshrinking time is adjusted in sections to eliminate the internal stress of the fabric;

[0014] S7. Graded water washing purification, the preshrunk fabric is sequentially subjected to weak acid ultrasonic cleaning, neutral high-pressure spray rinsing, and deionized water soaking cleaning to remove the residual impurities and excess additives on the surface of the fabric;

[0015] S8. Composite functional finishing reinforcement, the washed fabric is immersed in a silicone-polyether composite modified soft finishing agent for double-dip double-rolling treatment, the mass ratio of silicone to polyether is 6:4, so that the finishing agent is uniformly attached to the surface of the fabric fibers and penetrates into the fiber gaps;

[0016] S9. Multi-stage gradient setting treatment, using a three-stage hot air setting process to set the finished fabric, controlling the fabric shape through preheating, constant temperature holding, and gradient cooling processes, and real-time regulation of fabric tension during setting;

[0017] S10. Surface micro-nano structuring treatment, forming a uniform distribution of micron-scale grooves and nano-scale protrusion composite structure by nitrogen atmosphere low-temperature plasma surface micro-etching on the set fabric, to obtain a cool composite fabric.

[0018] Further, in the step S1, the mixing mass ratio of the cool polylactic acid-polyether ester blended hollow fiber and flax fiber is 38-42:58-62, the power of the argon atmosphere low-temperature plasma surface grafting of acrylic acid treatment is 45-52W, the treatment time is 18-23s, and the mass ratio of polyethylene glycol to chitosan in the polyethylene glycol-chitosan composite system is 7:3. The specific mass ratio of the cool polylactic acid-polyether ester blended hollow fiber and flax fiber here can take into account the cool conduction properties and skin-friendly breathability of the fiber, laying a foundation for uniform mixing for subsequent spinning and knitting. The power and time parameters of the argon atmosphere low-temperature plasma surface grafting of acrylic acid can precisely improve the surface activity of the cool fiber, enhance the interfacial bonding force with the flax fiber, and avoid problems such as broken ends and fuzz during spinning. The fixed mass ratio of polyethylene glycol to chitosan can optimize the moisture absorption performance of flax fiber, realizing the synergy of cool and moisture absorption functions.

[0019] Further, in the step S2, the dynamic twisting twist of the blended yarn is 380-430 twists per meter, the oil agent for four-stage online gradient oiling treatment is a composite system of white oil, Span-80 and polyoxyethylene sorbitan fatty acid ester, and the oiling rates of each stage are controlled as 0.6%, 0.9%, 1.1% and 0.8% respectively. The dynamic twisting twist of the blended yarn here can give the yarn appropriate strength and elasticity, meeting the requirements of knitting processing on the mechanical properties of the yarn and avoiding yarn breakage or deformation during knitting. The oil agent combination and oiling rate control of each stage of the four-stage online gradient oiling can form a uniform lubricating film on the surface of the yarn, reduce the frictional resistance during spinning and knitting, reduce fiber damage, and at the same time ensure the compatibility of the yarn with finishing agents later, without affecting the function of the fabric.

[0020] Further, the step S3, the needle pitch of the double needle bed double face knitting machine is 21-22 needles / inch, the frequency conversion yarn feeding speed is 7-8.5 m / min, the needle cylinder temperature control is 23-24℃, the needle disc temperature control is 20-21℃, and the plain rib double rib jacquard composite structure of the fabric base layer is arranged alternately according to the width ratio of 2:3:1. The needle pitch of the double needle bed double face knitting machine matches the frequency conversion yarn feeding speed, which can ensure the uniform density of the fabric base layer and avoid uneven defects. The temperature control of the needle cylinder and the needle disc can adapt to the contact requirements of the yarn and the needle during knitting, reduce the tension change of the yarn due to temperature fluctuation, and improve the forming stability of the fabric base layer. The width ratio design of the plain rib double rib jacquard composite structure makes the fabric base layer have stiffness, elasticity and structural stability, which not only meets the interweaving requirements of the subsequent composite layer, but also improves the wearing fit.

[0021] Further, the step S4, the core sheath mass ratio of the cool feeling functional yarn is 43-47:53-57, the spinning temperature of the concentric composite spinning process is 235-245℃, the air speed of the side blowing cooling is 1.0-1.1 m / s, the cooling temperature is 20-22℃, and the draft ratio is 3.8-4.2 times. The core sheath mass ratio of the cool feeling functional yarn can balance the heat conduction efficiency of the core layer cool feeling polyester-polyamide blend component and the skin-friendly moisture absorption performance of the sheath layer bamboo pulp viscose fiber. The temperature of the concentric composite spinning, the air speed of the side blowing cooling, the cooling temperature and the draft ratio parameters can ensure the uniform formation of the core sheath structure, avoid the core layer deviation or the sheath layer not tightly wrapped, and ensure the cool feeling durability and structural stability of the yarn.

[0022] Further, the step S5, when 1 composite layer loop is interwoven every 3 base layer loops, the needle bed displacement amount is controlled to be 0.35 mm; when 1 composite layer loop is interwoven every 4 base layer loops, the needle bed displacement amount is controlled to be 0.4 mm; when 1 composite layer loop is interwoven every 5 base layer loops, the needle bed displacement amount is controlled to be 0.45 mm, and the ratio of the needle bed movement frequency to the frequency conversion yarn feeding speed is 1:(2-2.5). The corresponding matching of the interweaving frequency and the needle bed displacement amount can form a stable periodic interweaving structure between the cool feeling functional yarn and the fabric base layer, which can avoid the problems of delamination and air permeability obstruction caused by traditional fixed spacing interweaving, and realize uniform distribution of cool feeling through spacing cycle adjustment. The ratio control of the needle bed movement frequency and the frequency conversion yarn feeding speed can ensure the regularity of loop formation during interweaving, avoid loop skewing or uneven density, and improve the structural consistency of the composite fabric.

[0023] Further, the multi-stage relaxation preshrinking process in step S6 is divided into three stages, the first stage preshrinking temperature is 43℃, the treatment time is 6min, the second stage preshrinking temperature is 45℃, the treatment time is 7min, the third stage preshrinking temperature is 47℃, the treatment time is 6min, and the total relaxation rate of the fabric is controlled to be 6-7%. The setting of the segmented temperature and time of the multi-stage relaxation preshrinking can gradually release the internal stress accumulated in the process of spinning and knitting, and avoid fabric wrinkles or size instability caused by one-time preshrinking. The control of the total relaxation rate can effectively reduce the shrinkage rate in the subsequent use of the fabric, ensure the size accuracy of the finished fabric, and improve the consistency of the wearing experience.

[0024] Further, the weak acid ultrasonic cleaning in step S7 has a pH value of 5.2-5.4, a cleaning temperature of 33-35℃, an ultrasonic power of 150-180W, and a cleaning time of 12-14min; the neutral high-pressure spray rinsing has a pressure of 0.3-0.4MPa and is rinsed for 3 times; and the deionized water immersion cleaning has a time of 10-11min. The pH value, temperature, power and time parameters of the weak acid ultrasonic cleaning can specifically remove the residual spinning oil and impurities on the surface of the fabric without damaging the modified groups and functional structures on the surface of the fiber. The pressure and number of times of the neutral high-pressure spray rinsing can completely wash away the residual acidic cleaning solution, avoiding the abnormal pH value of the fabric affecting the wearing comfort. The time of the deionized water immersion cleaning can further purify the fabric to create clean surface conditions for subsequent functional finishing.

[0025] Further, the concentration of the organic silicon-polyether composite modified soft finishing agent in step S8 is 10-11g / L, the first dip-nip pressure is 0.22MPa, the second dip-nip pressure is 0.28MPa, and the total nip rate is controlled to be 78-82%. The concentration setting of the organic silicon-polyether composite modified soft finishing agent can ensure that the finishing agent forms a uniform film on the surface of the fiber, and at the same time penetrates into the interstices of the fiber, taking into account the soft hand feeling and cool feeling functions of the fabric. The differential pressure and total nip rate control of the double-dip double-nip can make the finishing agent adhere uniformly, avoid local overfinishing or insufficient finishing, ensure the uniform softness of the fabric, and not affect the air permeability and cool feeling conduction of the fabric.

[0026] Further, the preheating section temperature of the three-section hot air setting process in step S9 is 105-108 DEG C, the temperature rising time is 2 min, the constant temperature section temperature is 133-137 DEG C, the constant temperature time is 5-5.5 min, the gradient cooling section gradually decreases from 133-137 DEG C to 43-47 DEG C, and the cooling time is 3 min; the tension of the fabric during the setting process is controlled to be 7-9 N; the power of the nitrogen atmosphere low-temperature plasma surface micro-etching in step S10 is 33-37 W, and the processing time is 9-11 s. The temperature, time and tension control of each section of the three-section hot air setting can gradually fix the organization structure and size form of the fabric, enhance the form stability of the fabric, and avoid the hardening or functional damage of the fabric caused by high-temperature instantaneous setting. The temperature change design of the gradient cooling section can reduce the residual stress of the fabric and ensure the flatness of the fabric. The power and time of the nitrogen atmosphere low-temperature plasma surface micro-etching can accurately form a micron-level groove and a nano-level protrusion composite structure, increase the contact area between the fabric and the skin, and strengthen the instantaneous cool feeling transmission efficiency, while not damaging the mechanical properties and soft hand feeling of the fabric.

[0027] The preparation method of the cool composite fabric of the present application is based on raw material synergistic modification, optimizes fiber compatibility through targeted modification of cool polylactic acid-polyether ester blended hollow fibers and flax fibers, and guarantees yarn adaptability through gradient blending spinning process; takes knitting process innovation as the core, uses double needle bed double face knitting to build a multifunctional composite organization base layer, realizes stable connection between the composite layer and the base layer by combining single face jacquard knitting variable pitch interweaving, and gives consideration to structural stability and air permeability; and finally, through segmented preshrinking, graded water washing and purification of the fabric base, composite functional finishing and multi-section gradient setting are used to improve softness and dimensional stability, and finally, surface micro-nano structuring treatment is used to enhance cool feeling transmission efficiency, so as to form a process system with full-process synergy and link adaptation, and realize balanced optimization of cool feeling, moisture absorption, skin friendliness and structural stability and other performances.

[0028] Compared with the prior art, the present application has the following advantages:

[0029] (1) The raw material synergistic modification and specific ratio design of the present application significantly improve the compatibility of cool fibers and carrier fibers, reduce quality problems in the spinning process, guarantee yarn uniformity and knitting forming stability, and lay a foundation for fabric comprehensive performance;

[0030] (2) The composite organization design of double needle bed double face knitting and the variable pitch interweaving process combination make the fabric base layer and the composite layer connect stably, avoid delamination, retain good air permeability, and give consideration to structural stability and wearing comfort;

[0031] (3) The synergistic effect of the core-sheath structure cool functional yarn and the surface micro-nano structuring treatment of the fabric increases the cool feeling transmission contact area, improves the instantaneous cool feeling effect, and the cool feeling performance is durable and stable;

[0032] (4) The silicone polyether composite modification soft finishing is matched with the multi-stage gradient setting process, excellent soft hand feeling is given to the fabric, the dimensional stability is ensured, and shrinkage deformation in use is reduced;

[0033] (5) The whole process optimization of the hierarchical washing and functional finishing realizes the synergistic improvement of cool feeling, moisture absorption and skin-friendly performance, solves the performance imbalance problem caused by single function optimization, and meets the use requirements in multiple scenes;

[0034] (6) The depth adaptation of the knitting process and the raw material modification and finishing technology forms a systematic preparation system, improves the fabric production efficiency and the finished product qualification rate, and promotes the quality upgrading of the cool feeling knitted fabric. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 is a flow chart of a preparation method of a cool feeling composite fabric of the present application. DETAILED DESCRIPTION

[0036] In order to facilitate the understanding of the present application, the present application will be described more fully, specifically and concretely with reference to the preferred embodiments and the accompanying drawings, but the scope of protection of the present application is not limited to the following specific embodiments.

[0037] Unless otherwise defined, all the professional terms used in the following have the same meaning as generally understood by those skilled in the art. The professional terms used in the present application are only for the purpose of describing the specific embodiments, and are not intended to limit the scope of protection of the present application.

[0038] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present application can be purchased from the market or can be prepared by existing methods.

[0039] Example 1

[0040] Reference Figure 1 A preparation method of a cool feeling composite fabric of the present application, comprising the following steps,

[0041] S1. Raw material combination and synergistic modification, selecting cool feeling polylactic acid-polyether ester blended hollow fiber and flax fiber as the basic raw material, the mass ratio of cool feeling polylactic acid-polyether ester blended hollow fiber and flax fiber is 40:60, the cool feeling polylactic acid-polyether ester blended hollow fiber is treated by argon atmosphere low temperature plasma surface grafting of acrylic acid, the treatment power is 48W, the treatment time is 20s, the flax fiber is treated by polyethylene glycol-chitosan composite system grafting modification, the mass ratio of polyethylene glycol and chitosan is 7:3;

[0042] S2. Gradient blending yarn is made by mixing the two modified fibers, and the process is sequentially carried out by airflow opening, four carding, four-stage drawing, double-zone heating and drawing, and dynamic twisting and spinning. The dynamic twisting degree of the blended yarn is 400 twists per meter. Four-stage online gradient oiling treatment is used during spinning, and the oil agent is a composite system of white oil, Span-80 and polyoxyethylene sorbitan fatty acid ester. The oiling rates of each stage are 0.6%, 0.9%, 1.1% and 0.8%, respectively;

[0043] S3. Double-system temperature-controlled knitting is made by using a double-needle bed double-sided knitting machine. The needle pitch of the knitting machine is 21 needles per inch, and the variable-frequency yarn feeding speed is 7.8 m / min. The knitting temperature is controlled by the needle cylinder independent temperature control module and the needle disc independent temperature control module. The needle cylinder temperature is 23°C, and the needle disc temperature is 20°C. The plain-doublerib-jacquard composite organization fabric base layer is formed by knitting. The composite organization is arranged alternately according to the width ratio of 2:3:1.

[0044] S4. Cool functional yarn preparation. Select cool polyester-polyamide blended chips and bamboo pulp viscose fibers to prepare cool functional yarn with a core-sheath structure by concentric composite spinning process. The core layer is a cool polyester-polyamide blended component, and the sheath layer is a bamboo pulp viscose fiber component. The mass ratio of the core to the sheath is 45:55. The core component is extruded through the center jet hole, and the sheath bamboo pulp viscose fiber is extruded through the peripheral ring-shaped jet hole. Side-blowing cooling technology is used during spinning. The side-blowing air pressure is 0.18 MPa. The vertical distance between the side-blowing device and the jet hole is 35 cm. The spinning temperature is 240°C. The side-blowing cooling air speed is 1.05 m / s. The cooling temperature is 21°C. The draw ratio is 4.0 times.

[0045] S5. Variable-distance interlacing composite forming. Variable-distance interlacing knitting is carried out on one side of the fabric base layer using a single-jacquard knitting machine. The interlacing frequency is adjusted in a cycle of 1 composite layer coil for every 3 base layer coils, 1 composite layer coil for every 4 base layer coils, and 1 composite layer coil for every 5 base layer coils. When 1 composite layer coil is interlaced for every 3 base layer coils, the needle bed displacement is 0.35 mm. When 1 composite layer coil is interlaced for every 4 base layer coils, the needle bed displacement is 0.4 mm. When 1 composite layer coil is interlaced for every 5 base layer coils, the needle bed displacement is 0.45 mm. The ratio of needle bed movement frequency to variable-frequency yarn feeding speed is 1:2.2, which makes the cool functional yarn and the fabric base layer form periodic interlacing connection and build the composite layer.

[0046] S6. Segment pre-shrinking relaxation treatment, the interwoven composite fabric after forming is subjected to multi-stage relaxation pre-shrinking treatment, which is divided into three stages, the first stage pre-shrinking temperature is 43℃, the treatment time is 6min, the second stage pre-shrinking temperature is 45℃, the treatment time is 7min, the third stage pre-shrinking temperature is 47℃, the treatment time is 6min, and the total relaxation rate of the fabric is 6.5%;

[0047] S7. Graded water washing purification, the pre-shrunk fabric is sequentially subjected to weak acid ultrasonic cleaning, neutral high-pressure spray rinsing and deionized water soaking cleaning, the pH value of the weak acid ultrasonic cleaning is 5.3, the cleaning temperature is 34℃, the ultrasonic power is 165W, the cleaning time is 13min, the pressure of the neutral high-pressure spray rinsing is 0.35MPa, the rinsing times is 3, and the deionized water soaking cleaning time is 10.5min;

[0048] S8. Composite functional finishing reinforcement, the washed fabric is immersed in a silicone-polyether composite modified soft finishing agent for double-dip double-roller treatment, the mass ratio of silicone to polyether is 6:4, the finishing agent concentration is 10.5g / L, the first dip-roller pressure is 0.22MPa, the second dip-roller pressure is 0.28MPa, and the total roller residual rate is 80%, so that the finishing agent is uniformly attached to the surface of the fabric fibers and penetrates into the fiber interstices;

[0049] S9. Multi-stage gradient setting treatment, the finished fabric is subjected to setting by adopting a three-stage hot air setting process, the preheating section temperature is 106℃, the temperature rising time is 2min, the constant temperature section temperature is 135℃, the constant temperature time is 5.2min, the gradient cooling section gradually decreases from 135℃ to 45℃, and the cooling time is 3min, and the fabric tension is controlled to be 8N during the setting process;

[0050] S10. Surface micro-nano structuring treatment, the set fabric is subjected to nitrogen atmosphere low temperature plasma surface micro-etching, the treatment power is 35W, and the treatment time is 10s, to form a uniform distribution of micron-level grooves and nano-level protrusion composite structure, to obtain a cool composite fabric.

[0051] Example 2

[0052] The difference between this example and Example 1 is that in step S1, the mass ratio of the cool polylactic acid-polyether ester blended hollow fiber to flax fiber is 38:62, the power of the argon atmosphere low temperature plasma surface grafting of acrylic acid treatment is 45W, and the treatment time is 18s, and the mass ratio of polyethylene glycol to chitosan in the polyethylene glycol-chitosan composite system remains unchanged at 7:3.

[0053] Example 3

[0054] The difference between this embodiment and embodiment 1 is that in step S5, the interlacing frequency is adjusted in a reverse cycle of 1 composite layer coil interlaced every 4 base layer coils, 1 composite layer coil interlaced every 5 base layer coils, and 1 composite layer coil interlaced every 3 base layer coils, and the needle bed displacement is adjusted synchronously by 0.4 mm, 0.45 mm, and 0.35 mm, respectively, and the ratio of the needle bed movement frequency to the variable speed yarn feeding speed remains unchanged at 1:2.2.

[0055] Comparative Example 1

[0056] The difference between this comparative example and embodiment 1 is that in step S1, the cool feeling polylactic acid-polyether ester blended hollow fiber is not subjected to argon atmosphere low temperature plasma surface grafting of acrylic acid, and the flax fiber is not subjected to polyethylene glycol-chitosan composite system grafting modification treatment.

[0057] Comparative Example 2

[0058] The difference between this comparative example and embodiment 1 is that in step S5, fixed pitch staggered interlacing knitting is used, the interlacing frequency is 1 composite layer coil interlaced every 4 base layer coils, and the needle bed displacement is fixed at 0.4 mm, without cycle adjustment.

[0059] Comparative Example 3

[0060] The difference between this comparative example and embodiment 1 is that in step S8, a single silicone soft finishing agent is used instead of the silicone-polyether composite modified soft finishing agent, and the finishing agent concentration, as well as the pressure and total rolling rate of the double-dip double-roller treatment, are consistent with those of embodiment 1.

[0061] Comparative Example 4

[0062] The difference between this comparative example and embodiment 1 is that the surface micro-nano structuring step of step S10 is omitted, i.e., the fabric after multi-section gradient shaping treatment is directly used as the finished product.

[0063] The fabrics in examples 1-3 and comparative examples 1-4 are tested, and the testing method is as follows:

[0064] Cool feeling conduction time: a skin contact type temperature sensor is used to record the time when the temperature of the fabric drops to 32°C after contacting a 37°C simulated skin;

[0065] Composite layer peeling strength: according to the textile peeling strength test standard, a tensile testing machine is used to perform a T-type peeling test at a speed of 50 mm / min, the average peeling force is recorded and converted into unit width strength;

[0066] Fabric softness: a digital fabric softness instrument is used to test the bending deformation amount of the fabric under a certain pressure, and the deformation millimeter number is used to represent the softness;

[0067] Moisture absorption rate: using the weight method, the ratio of the mass increment after saturated moisture absorption to the initial mass of the fabric in the environment of 25℃ and relative humidity of 65% is tested;

[0068] Cool feeling retention rate after 50 times of washing: the fabric is repeatedly washed 50 times according to the standard washing procedure, the cool feeling transmission time before and after washing is tested, and the ratio of the cool feeling transmission efficiency after washing to that before washing is calculated;

[0069] Shrinkage rate: according to the standard of textile dimensional change test, the dimensional change rates of the fabric in the warp and weft directions after standard washing and drying are measured, and the average value is taken as the final shrinkage rate.

[0070] Table 1: Experimental results of examples 1-3 and comparative examples 1-4

[0071]

[0072] In summary, referring to Table 1, the cool feeling transmission efficiency, composite layer connection stability, softness, moisture absorption performance and cool feeling durability of the examples are overall significantly better than those of the comparative examples, and the shrinkage rate is better controlled.

[0073] Comparative example 1 has poor compatibility between the cool feeling fiber and the flax fiber due to the lack of raw material modification, and the fiber is damaged more during spinning, resulting in low cool feeling transmission efficiency, insufficient composite layer peeling strength, limited moisture absorption performance and easy loss of cool feeling after washing, and high shrinkage rate; Comparative example 2 uses a fixed pitch interweaving process, and the connection mode between the composite layer and the base layer is single, making it difficult to form a stable periodic bonding structure, so the composite layer peeling strength is low, the cool feeling distribution uniformity is insufficient, and the cool feeling retention rate decreases; Comparative example 3 uses a single silicone soft finishing agent, which lacks the synergistic effect of polyether components, so the softness of the fabric is limitedly improved, and the combination stability of the finishing agent and the fiber is insufficient, resulting in a decrease in cool feeling retention rate after washing; Comparative example 4 does not perform surface micro-nano structuring treatment, so the contact area between the fabric and the skin is small, the cool feeling transmission path is limited, the cool feeling transmission time is prolonged, and the micro-nano structure lacks the strengthening effect on the cool feeling function, so the cool feeling retention rate after washing is low.

[0074] Example 1 has balanced and excellent performance in all aspects due to the synergistic effect of raw material modification, variable pitch interweaving, composite finishing and micro-nano structuring treatment through the whole process parameter adaptation.

[0075] Example 2 has a slightly decreased cool feeling transmission efficiency due to a slightly lower proportion of cool feeling fiber and plasma treatment parameter adjustment, but the moisture absorption rate is significantly improved due to the increased proportion of flax fiber, and the other performances remain stable.

[0076] Example 3 has slightly fluctuating cool feeling transmission time, composite layer peeling strength and softness compared with example 1 due to the slight change in the uniformity of the connection between the composite layer and the base layer by adjusting the interweaving frequency cycle sequence, but the overall performance remains at a high level.

Claims

1. A method for preparing a cool composite fabric, characterized by: Comprise the following steps, S1. Raw material combination and synergistic modification, select cool poly lactic acid-polyether ester blended hollow fiber and flax fiber as the basis of raw material, argon atmosphere low temperature plasma surface grafting acrylic acid treatment is carried out to cool poly lactic acid-polyether ester blended hollow fiber, polyethylene glycol-chitosan composite system grafting modification treatment is carried out to flax fiber; S2. Gradient blending into yarn, mix the modified two fibers according to the set proportion, pass through air opening, four carding, four stage drawing, double zone heating roving drafting, dynamic twisting and spinning process in turn to make blended yarn, four section type online gradient oiling treatment is adopted in the spinning process; S3. Double system temperature control knitting into base, adopt double needle bed double face knitting machine for knitting processing, set the needle pitch and variable frequency yarn feeding speed of knitting machine, adjust and control the knitting temperature through needle cylinder independent temperature control module and needle disc independent temperature control module respectively, and the fabric base layer of plain weave-double rib-weft pattern composite organization is knitted; S4. Cool functional yarn preparation, select cool polyester-polyamide blended chip and bamboo pulp viscose fiber, prepare the cool functional yarn with core-sheath structure through concentric composite spinning process, the core layer is cool polyester-polyamide blended component, the sheath layer is bamboo pulp viscose fiber component, the core layer component is extruded through the center jet orifice, the sheath layer bamboo pulp viscose fiber is extruded through the peripheral ring jet orifice, side blowing cooling technology is adopted in the spinning process, the side blowing air pressure is 0.15-0.2 MPa, the vertical distance between the side blowing device and the jet orifice is 30-40 cm; S5. Variable pitch interweaving composite forming, adopt single jacquard knitting machine to carry out variable pitch interweaving knitting on one side of the fabric base layer, the interweaving frequency is adjusted in a cycle of 1 composite layer coil interweaving every 3 base layer coils, 1 composite layer coil interweaving every 4 base layer coils and 1 composite layer coil interweaving every 5 base layer coils, so that the cool functional yarn and the fabric base layer form periodic interweaving connection to build the composite layer, the needle bed displacement of the knitting machine is adjusted synchronously according to the corresponding rule during interweaving, and the needle bed movement frequency and the yarn feeding speed are kept adaptive; S6. Sectional preshrinking relaxation treatment, the composite fabric after interweaving is formed is subjected to multi-section relaxation preshrinking treatment, the preshrinking temperature is controlled by gradient heating, and the preshrinking time is adjusted in sections to eliminate the internal stress of the fabric; S7. Graded washing purification, the preshrunk fabric is sequentially subjected to weak acid ultrasonic cleaning, neutral high-pressure spray rinsing and deionized water soaking cleaning to remove the residual impurities and excess additives on the surface of the fabric; S8. Composite functional finishing and strengthening, the washed fabric is immersed in silicone-polyether composite modified soft finishing agent for double immersion and double rolling treatment, the mass ratio of silicone to polyether is 6:4, so that the finishing agent is evenly attached to the surface of the fabric fibers and penetrates into the fiber gap; S9. Multi-section gradient setting treatment, adopt three-section hot air setting process to set the finished fabric, control the fabric shape through preheating, constant temperature keeping and gradient cooling process, and adjust the fabric tension in real time during setting. S10. Surface micro-nano structure processing, the surface micro-etching of the finished fabric in nitrogen atmosphere low temperature plasma is carried out, the uniform distribution of micron level groove and nano level convex composite structure is formed, and the cool composite fabric is obtained.

2. The method of claim 1, wherein the method further comprises: The mixing mass ratio of the cool poly-lactic acid-poly-ether ester blended hollow fiber and flax fiber in the step S1 is 38-42:58-62, the power of the argon atmosphere low temperature plasma surface grafting acrylic treatment is 45-52 W, and the treatment time is 18-23 s; the mass ratio of polyethylene glycol and chitosan in the polyethylene glycol-chitosan composite system is 7:

3.

3. The method of claim 1, wherein the method further comprises: The dynamic twisting twist of the blended yarn in the step S2 is 380-430 twists per meter, the oil agent of the four-section online gradient oiling treatment is a composite system of white oil, Span-80 and polyoxyethylene sorbitan fatty acid ester, and the oiling rates of each section are controlled as 0.6%, 0.9%, 1.1% and 0.8% in turn.

4. The method of claim 1, wherein the method further comprises: The needle pitch of the double needle bed double face knitting machine in the step S3 is 21-22 needles per inch, the frequency conversion yarn feeding speed is 7-8.5 m / min, the needle cylinder temperature is controlled as 23-24 DEG C, the needle disc temperature is controlled as 20-21 DEG C, and the plain stitch-double rib stitch-jacquard composite structure of the fabric base layer is arranged alternately according to the width ratio of 2:3:

1.

5. The method of claim 1, wherein the method further comprises: The core sheath mass ratio of the cool functional yarn in the step S4 is 43-47:53-57, the spinning temperature of the concentric composite spinning process is 235-245 DEG C, the air speed of the side blowing cooling is 1.0-1.1 m / s, the cooling temperature is 20-22 DEG C, and the draft ratio is 3.8-4.2 times.

6. The method of claim 1, wherein the method further comprises: When one composite layer loop is interwoven every 3 base layer loops in the step S5, the needle bed displacement amount is controlled as 0.35 mm; when one composite layer loop is interwoven every 4 base layer loops, the needle bed displacement amount is controlled as 0.4 mm; when one composite layer loop is interwoven every 5 base layer loops, the needle bed displacement amount is controlled as 0.45 mm, and the ratio of the needle bed movement frequency to the frequency conversion yarn feeding speed is 1:(2-2.5).

7. The method of claim 1, wherein the method further comprises: The multi-section relaxation preshrinking treatment in the step S6 is divided into three sections, the first section preshrinking temperature is 43 DEG C, the treatment time is 6 min, the second section preshrinking temperature is 45 DEG C, the treatment time is 7 min, the third section preshrinking temperature is 47 DEG C, the treatment time is 6 min, and the total relaxation rate of the fabric is controlled as 6-7%.

8. The method of claim 1, wherein the method further comprises: The pH value of the weak acid ultrasonic cleaning in the step S7 is 5.2-5.4, the cleaning temperature is 33-35 DEG C, the ultrasonic power is 150-180 W, and the cleaning time is 12-14 min; the pressure of the neutral high pressure spray rinsing is 0.3-0.4 MPa, the rinsing times are 3, and the deionized water immersion cleaning time is 10-11 min.

9. The method of claim 1, wherein the method further comprises: The concentration of the organic silicon-polyether composite modified soft finishing agent in the step S8 is 10-11 g / L, the first dip-nip pressure is 0.22 MPa, the second dip-nip pressure is 0.28 MPa, and the total nip rate is controlled as 78-82%.

10. The method of claim 1, wherein the method further comprises: The temperature of the preheating section of the three-section hot air setting process in the step S9 is 105-108 DEG C, the temperature rising time is 2 min, the temperature of the constant temperature section is 133-137 DEG C, the constant temperature time is 5-5.5 min, the temperature of the gradient cooling section is gradually reduced from 133-137 DEG C to 43-47 DEG C, the temperature reducing time is 3 min, and the tension of the fabric during the setting process is controlled to be 7-9 N; the power of the nitrogen atmosphere low temperature plasma surface micro-etching in the step S10 is 33-37 W, and the processing time is 9-11 s.

Images