A high-elasticity lace composite fabric and its production process

Abstract

This invention discloses a high-elasticity lace composite fabric and its production process. It uses 20-denier Lycra hot-melt spandex open-knit yarn as jacquard yarn, 210-denier Lycra spandex as elastic reinforcing yarn, and 70-denier nylon or polyester filament as comb yarn. Two spandex working threads are used in a mirror cross-threading pattern with one thread through one open and one open thread through another, combined with a determined 3-needle transverse shift, to construct an "X"-shaped cross-elastic network. The optimal ECC range is determined to be 4.8-5.5 using a marginal gain optimization method, and the transverse shift is calculated to be 3 needles. The setting temperature is determined by the Arrhenius equation to be within the range of 175℃-200℃, causing the hot-melt spandex skin to melt and bond the yarn cross nodes. The setting width ratio is determined by a linkage control formula. The resulting fabric has a longitudinal elastic stretch ratio of 1:2.5-1:2.8, a transverse elastic stretch ratio of 1:1.8-1:2.0, an elastic recovery rate ≥90%, and does not unravel when cut arbitrarily.

Description

Technical Field

[0001] This invention relates to the field of textile technology, specifically to a high-elasticity lace composite fabric and its production process. Background Technology

[0002] Lace fabric is a type of openwork patterned fabric woven on a warp knitting machine using methods such as yarn looping, weft insertion, and jacquard weaving.

[0003] Several solutions for elastic lace fabrics exist in the prior art. For example, patent CN102975411A discloses an elastic lace fabric with a multi-layer structure consisting of a breathable layer, a fiber layer, and a lace base layer bonded together with an adhesive. The limitations of this solution are that the multi-layer structure results in a heavy fabric with poor breathability; the adhesive layer restricts the relative sliding of the yarns, hindering elastic deformation; and the adhesive is prone to fatigue cracking after repeated stretching, leading to poor durability. Chinese patent CN105951262A discloses a lace fabric that prevents pilling and snagging, achieved by partially melting ultrafine spandex fibers under high-temperature and humid heat treatment to form particles, creating irregular adhesion between the yarns. The limitations of this solution are that the elastic recovery rate of the partially melted spandex fibers decreases significantly, and the distribution of the formed particle bonding points is uneven, resulting in unstable cutability. Chinese patent CN202175822U discloses a multi-comb warp-knitted jacquard fabric that achieves a three-dimensional effect through the combination of weft yarn and pressing yarn, but it does not involve a special design of the spandex elastic system, resulting in limited elastic performance.

[0004] Analysis reveals that the fundamental reasons why existing technologies cannot simultaneously achieve four-way stretch, arbitrary cutting, and rich patterns are as follows: First, there is a conflict between the working lines for elasticity and pattern making. The number of guide bars on a warp knitting machine is limited; if more working lines are allocated to spandex to enhance elasticity, the number of working lines for pattern making decreases, thus limiting the richness of patterns. Second, there is a conflict in the physical mechanisms of elasticity and arbitrary cutting. Elasticity requires spandex yarn to have ample free movement within the fabric, while arbitrary cutting requires the yarn intersections to be fixed to prevent unraveling. Third, there is the multi-parameter coupling and empirical dependence of elasticity performance. The elasticity of the fabric is simultaneously affected by dozens of process parameters, including spandex linear density, transverse displacement, yarn feed length, yarn threading method, loop density, setting width, and setting temperature. These parameters have nonlinear coupling relationships, and existing technologies lack quantitative mathematical models to describe this complex relationship, making it difficult to accurately determine the process parameters. Summary of the Invention

[0005] To solve the above technical problems, the present invention provides the following technical solution: a production process for a high-elasticity lace composite fabric, comprising the following steps: Step 1, yarn preparation: 20 denier Lycra hot-melt spandex hollow-wrapped yarn is selected as Jacquard yarn, 210 denier Lycra spandex as elastic reinforcing yarn, and 70 denier nylon filament or 70 denier polyester filament as combed yarn; the 20 denier Lycra hot-melt spandex hollow-wrapped yarn has a core-sheath structure, with the core layer being low-melting-point spandex fiber and the sheath layer being low-melting-point thermoplastic... The resin has a skin melting point lower than the core softening point; Step 2, warping and head configuration: The 210 denier Lycra spandex is warped with a pre-stretch rate of 60%; the 20 denier Lycra hot-melt spandex yarn is fully threaded into two sets of 303 head yarns, the 210 denier Lycra spandex is threaded into two sets of 303 head yarns respectively, and the 70 denier nylon filament or 70 denier polyester filament is threaded into one set of 303 head yarns; Step 3, yarn threading: In Karl Mayer RSJ 5 / 1 On an EL-type warp-knitting jacquard machine, model number E24, with a working width of 134 inches and a total needle count of 3216, the 20 denier Lycra hot-melt spandex yarn is fully threaded onto two jacquard working lines. The 70 denier nylon filament or 70 denier polyester filament is threaded onto the pattern comb working line. The 210 denier Lycra spandex is configured through two spandex working lines using a mirror-image cross-threading method. The first spandex working line threaded the spandex yarn into odd-numbered needle positions and left it unthreaded into even-numbered needle positions; the second spandex working line threaded the spandex yarn into even-numbered needle positions and left it unthreaded into odd-numbered needle positions. The threading holes of the two spandex working lines are completely complementary. Step four: Knitting: Set the lateral movement of both spandex working lines to 3 needles, and set the feed length of the spandex yarn per horizontal row. The length is 12 mm, and the longitudinal density on the machine is set to 15 rows per centimeter; the first spandex working thread is positioned as 1−0 / 3−4 / / , and the second spandex working thread is positioned as 4−3 / 0−1 / / . The positions of the two spandex working threads are mirror-symmetrical, forming a cross-elastic network structure within the span of 3 needles; Step 5, setting: The ratio of the finished coil density to the machine coil density is set to 2.0 to 2.3, the setting temperature is 175 degrees Celsius to 200 degrees Celsius, and the setting time is 30 to 60 seconds; During the setting process, the heat-melting component of the outer layer of the 20 denier Lycra hot-melt spandex empty yarn melts and diffuses along the yarn cross nodes. After cooling, it forms adhesive points, fixing the cross nodes of the jacquard yarn with the combed yarn and the elastic reinforcing yarn.

[0006] Preferably, in step four, the lateral coverage width of a single spandex yarn corresponding to the 3-needle lateral shift is 3.174 mm, the included angle between two crossed spandex yarns in the cross elastic network formed by the two spandex working lines is 45.6 degrees, and the spacing between adjacent spandex yarns is 2 needle pitches.

[0007] Preferably, in step five, when the ratio of the finished coil density to the on-machine coil density is set to 2.3, the ratio of the shaping width to the on-machine width is 0.99, and the shaping width shrinks by 0.86% relative to the on-machine width.

[0008] Preferably, in step five, when the ratio of the finished coil density to the on-machine coil density is set to 2.0, the ratio of the shaping width to the on-machine width is 0.86, and the width shrinks by 14% relative to the on-machine width during shaping, and the fabric undergoes pre-shrinkage deformation in the transverse direction.

[0009] Preferably, in step five, the lower limit of the setting temperature (175 degrees Celsius) and the upper limit of the setting temperature (200 degrees Celsius) are determined by the melt diffusion kinetics of the hot-melt components. When the setting temperature is below 175 degrees Celsius, the melt diffusion of the hot-melt components is insufficient, and the proportion of effective bonding nodes to the total number of bondable nodes is less than 81%. When the setting temperature is above 200 degrees Celsius, the elastic recovery rate of the 210 denier Lycra spandex decreases due to high-temperature damage.

[0010] Preferably, in step three, the number of spandex yarns threaded into the first spandex working line is 1608, the number of spandex yarns threaded into the second spandex working line is 1608, and the spandex yarns of the two spandex working lines are arranged alternately in space.

[0011] Preferably, the 20 denier Lycra hot-melt spandex hollow yarn has a sheath melting point of 120 to 140 degrees Celsius and a core softening point of 160 to 180 degrees Celsius; the 210 denier Lycra spandex has a breaking elongation of 500% to 700% and an elastic recovery rate of 95% to 99% under 200% elongation conditions.

[0012] To solve the above-mentioned technical problems, the present invention also provides the following technical solution: a high-elasticity lace composite fabric, prepared using the above-mentioned production process, wherein the longitudinal elastic stretch ratio of the composite fabric is 1:2.5 to 1:2.8, and the transverse elastic stretch ratio is 1:1.8 to 1:2.0; the longitudinal elastic recovery rate is not less than 90%, and the transverse elastic recovery rate is not less than 90%; after the fabric is cut in the warp, weft, and 45-degree oblique direction, the length of the unraveling length of the cut edge after mechanical friction is 0 mm; the fabric weight is 145 to 170 grams per square meter; compared with conventional lace fabric, the longitudinal elasticity is increased by more than 20%, and the transverse elasticity is increased by more than 30%.

[0013] Preferably, in the composite fabric, the heat-melting component of the outer layer of the 20 denier Lycra heat-melting spandex loose yarn forms bonding points at the intersection of the jacquard yarn, the combed yarn, and the elastic reinforcing yarn. The average spacing between the bonding points is 1.4 to 1.6 mm, and the number of effective bonding points per square centimeter of fabric is 4565.

[0014] Preferably, in the composite fabric, jacquard yarn serves as the base structure skeleton and heat-bonding function, elastic reinforcing yarn serves as the elasticity-providing function, and combed yarn serves as the pattern expression function, with the functions of the three yarns being independent of each other.

[0015] This invention provides a high-elasticity lace composite fabric and its production process, which has the following beneficial effects: the longitudinal elastic stretch ratio reaches 1:2.5-1:2.8, the transverse elastic stretch ratio reaches 1:1.8-1:2.0, and the elastic recovery rate is ≥90%; the heat-melt bonding points are distributed at the yarn intersection nodes, and the edges do not fray, curl, or snag after cutting in any direction, eliminating the need for edge binding; through the decoupling design of yarn functions, the elastic function and the pattern function are independent, and the pattern comb working line can be used for free pattern design; the ECC model and the Arrhenius dynamics model provide quantitative basis for determining process parameters, and the optimal parameter combination can be quickly determined according to different elasticity requirements; the jacquard yarn is only 20 denier, the base structure is delicate and uniform, and the fabric weight is 148-165g / m², making it suitable for high-end close-fitting clothing. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the working line diagram and technical parameters of the Karl Mayer RSJ 5 / 1 EL model in an embodiment of the present invention.

[0017] Figure 2 This is a schematic diagram of the initial process flow according to an embodiment of the present invention.

[0018] Figure 3 This is a mirror cross-positioning process diagram of the spandex working line in an embodiment of the present invention.

[0019] Figure 4 This is an enlarged schematic diagram of the movement pattern of the spandex working line in an embodiment of the present invention.

[0020] Figure 5 This is a schematic diagram of the combined positioning after adjusting the spandex lateral displacement in an embodiment of the present invention. Detailed Implementation

[0021] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0022] This invention aims to solve the following technical problems: how to achieve a unified performance of four-way stretch, arbitrary cutting, and rich patterns through yarn function decoupling design under a limited configuration of 5 working lines; how to eliminate the elasticity unevenness caused by large transverse displacement (2-3 needles) and achieve a uniform four-way stretch effect by constructing a mirrored cross elastic network; how to establish an elastic coverage coefficient (ECC) mathematical model to quantify the elastic contribution of spandex as a function of process parameters, and achieve accurate prediction and control of elastic performance; and how to guide the design of heat setting process parameters through the Arrhenius equation to achieve reliable arbitrary cutting heat melt bonding without damaging the elasticity of spandex.

[0023] Specifically, this invention provides a production process for high-elasticity lace composite fabric, including the following steps:

[0024] Step 1: Yarn preparation: Select 20 denier Lycra hot-melt spandex hollow yarn as Jacquard yarn, 210 denier Lycra spandex as elastic reinforcing yarn, and 70 denier nylon filament or 70 denier polyester filament as combed yarn; the 20 denier Lycra hot-melt spandex hollow yarn has a core-sheath structure, with the core layer being low-melting-point spandex fiber and the sheath layer being low-melting-point thermoplastic resin, and the melting point of the sheath layer being lower than the softening point of the core layer;

[0025] Step 2, Warping and Header Configuration: Warp the 210 denier Lycra spandex with a pre-stretch rate of 60%; thread the 20 denier Lycra hot melt spandex loose yarn fully onto two sets of 303 headers; thread the 210 denier Lycra spandex into two sets of 303 headers respectively; thread the 70 denier nylon filament or 70 denier polyester filament into one set of 303 headers;

[0026] Step 3, Yarn Threading: On a Karl Mayer RSJ 5 / 1 EL warp knitting jacquard machine, size E24, working width 134 inches, total needle count 3216, fully thread 20 denier Lycra hot-melt spandex loose yarn onto two jacquard working lines. Thread 70 denier nylon filament or 70 denier polyester filament into the comb working line. Thread 210 denier Lycra spandex through two spandex working lines using a mirror cross-threading method. The first spandex working line threads spandex yarn into odd-numbered needle positions and leaves it loose into even-numbered needle positions. The second spandex working line threads spandex yarn into even-numbered needle positions and leaves it loose into odd-numbered needle positions. The threading holes of the two spandex working lines are completely complementary.

[0027] Step 4, weaving: Set the transverse shift of both spandex working threads to 3 needles, set the feed length of each row of spandex yarn to 12 mm, and set the longitudinal density on the machine to 15 rows per centimeter; the position of the first spandex working thread is 1−0 / 3−4 / / , and the position of the second spandex working thread is 4−3 / 0−1 / / . The positions of the two spandex working threads are mirror symmetrical, forming a cross elastic network structure within the 3 needle transverse shift span;

[0028] Step 5, Setting: Set the ratio of the finished coil density to the on-machine coil density to be 2.0 to 2.3, the setting temperature to be 175 degrees Celsius to 200 degrees Celsius, and the setting time to be 30 to 60 seconds; During the setting process, the heat-melting components of the outer layer of the 20 denier Lycra hot-melt spandex loose yarn melt and diffuse along the yarn cross nodes, forming adhesive points after cooling, thus fixing the cross nodes of the jacquard yarn with the combed yarn and the elastic reinforcing yarn.

[0029] In step four, the lateral coverage width of a single spandex yarn corresponding to the 3-needle transverse shift is 3.174 mm. The included angle between the two cross spandex yarns in the cross elastic network formed by the two spandex working lines is 45.6 degrees, and the spacing between adjacent spandex yarns is 2 needle pitches.

[0030] In step five, when the ratio of the finished coil density to the on-machine coil density is set to 2.3, the ratio of the shaped width to the on-machine width is 0.99, and the width shrinks by 0.86% relative to the on-machine width during shaping.

[0031] In step five, when the ratio of the finished coil density to the on-machine coil density is set to 2.0, the ratio of the shaping width to the on-machine width is 0.86. During shaping, the width shrinks by 14% relative to the on-machine width, and the fabric undergoes pre-shrinkage deformation in the transverse direction.

[0032] In step five, the lower limit of the setting temperature of 175 degrees Celsius and the upper limit of 200 degrees Celsius are determined by the melt diffusion kinetics of the hot melt component. When the setting temperature is below 175 degrees Celsius, the melt diffusion of the hot melt component is insufficient, and the proportion of effective bonding nodes to the total number of bondable nodes is less than 81%. When the setting temperature is above 200 degrees Celsius, the elastic recovery rate of 210 denier Lycra spandex decreases due to high temperature damage.

[0033] In step three, the number of spandex yarns inserted into the first spandex working line is 1608, the number of spandex yarns inserted into the second spandex working line is 1608, and the spandex yarns of the two spandex working lines are arranged alternately in space.

[0034] The outer layer of 20 denier Lycra hot melt spandex hollow yarn has a melting point of 120 to 140 degrees Celsius, and the core layer softening point is 160 to 180 degrees Celsius; the breaking elongation of 210 denier Lycra spandex is 500% to 700%, and the elastic recovery rate under 200% elongation is 95% to 99%.

[0035] This invention also provides a high-elasticity lace composite fabric, prepared using the above-mentioned production process. The longitudinal elastic stretch ratio of the composite fabric is 1:2.5 to 1:2.8, and the transverse elastic stretch ratio is 1:1.8 to 1:2.0; the longitudinal elastic recovery rate is not less than 90%, and the transverse elastic recovery rate is not less than 90%; after the fabric is cut in the warp, weft, and 45-degree oblique direction, the length of the unraveling length of the cut edge after mechanical friction is 0 mm; the fabric weight is 145 to 170 grams per square meter; compared with conventional lace fabric, the longitudinal elasticity is increased by more than 20%, and the transverse elasticity is increased by more than 30%.

[0036] In the composite fabric, the heat-melting component of the outer layer of the 20 denier Lycra heat-melting spandex air-covered yarn forms bonding points at the intersection of the jacquard yarn, the combed yarn, and the elastic reinforcing yarn. The average spacing between the bonding points is 1.4 to 1.6 mm, and the number of effective bonding points per square centimeter of fabric is 4565.

[0037] In composite fabrics, jacquard yarn serves as the structural framework and heat-bonding agent, elastic reinforcing yarn provides elasticity, and combed yarn expresses patterns. The functions of the three yarns are independent of each other.

[0038] For details, please refer to the appendix. Figure 1 Appendix Figure 2 Appendix Figure 3 Appendix Figure 4 and appendix Figure 5 The present invention provides the following specific solution: a production process for high-elasticity lace composite fabric, which uses a Karl Mayer RSJ 5 / 1 EL warp knitting jacquard machine. The machine model is E24 (i.e., 24 needles per 25.4mm needle bed length), the needle pitch is 1.058mm, the working width is 134 inches (approximately 3403.6mm), the total number of needles is 3216, and the number of working threads is 5.

[0039] Specifically, the main technical parameters of this model are shown in Table A below:

[0040] Table A: Model Technical Specifications

[0041] model RSJ 5 / 1 EL (Rascheltronic®) serial number E24 (meaning 24 needles per 25.4mm (1 inch) needle bed length) Stitch 25.4 / 24≈1.058mm Working width 134 inches (approximately 3403.6 mm) Total number of stitches 134×24 = 3216 pieces Number of working lines 5 items (GB1-GB5 or GB1-GB6, of which 2 are for Jacquard control) Jacquard system Piezoelectric Jacquard (EL electronic control) Maximum weaving speed Approximately 1100 r / min Methods of sending scriptures Electronic scripture delivery (EBA system)

[0042] The fabric production process includes the following steps: yarn selection and preparation → warping → yarn threading configuration → weaving process parameter setting (including ECC optimization of transverse shift) → greige fabric weaving → heat setting (including Arrhenius parameter optimization) → dyeing → finishing → finished product inspection.

[0043] Specifically, the production process includes the following steps:

[0044] Step 1: Yarn Preparation – Use 20 denier Lycra hot-melt spandex empty-wrapped yarn as jacquard yarn, 210 denier Lycra spandex as elastic reinforcing yarn, and 70 denier nylon or polyester filament as combed yarn. The 20 denier Lycra hot-melt spandex empty-wrapped yarn has a core-sheath structure, with a core layer of low-melting-point spandex fiber and a sheath layer of low-melting-point thermoplastic polyurethane or copolyamide resin. The sheath melting point is lower than the core softening point. The 210 denier Lycra spandex has a molecular structure composed of a block copolymer consisting of alternating polyester or polyether soft segments and diisocyanate hard segments. The soft segments provide high elongation, while the hard segments provide high resilience.

[0045] It should be noted that the three core functions of the fabric (elasticity, heat-bonding, and pattern expression) are assigned to three yarns with different characteristics, which are then performed independently by different work lines, and the functions do not interfere with each other.

[0046] (I) Jacquard yarn - 20D Lycra hot melt spandex empty yarn

[0047] 1. Definition and Structure: 20D Lycra hot-melt spandex air-covered yarn (ACY) is a composite yarn made with 20 denier hot-melt spandex as the core layer and low-melting-point polyurethane resin as the sheath layer, processed through an air-jet covering process. Its structure is "core-sheath type".

[0048] Core layer: 20D Lycra hot-melt spandex—This spandex, based on conventional polyurethane elastic fibers (block copolymers composed of alternating polyester or polyether soft segments and diisocyanate hard segments), reduces the regularity of the molecular chains and the crystallinity of the hard segments by introducing asymmetric 2,4-MDI (diphenylmethane diisocyanate) or copolymerized polyether glycols (such as copolymers of tetrahydrofuran and branched glycols). This lowers the softening temperature of the spandex from the conventional 200°C or higher to approximately 160-180°C. The core layer provides an elastic skeleton function.

[0049] Skin layer: A layer of low-melting-point thermoplastic polyurethane (TPU) or copolyamide (CoPA) resin is coated onto the surface of the core layer using an air-coating process. The melting point of the skin layer is approximately 120-140℃. During the high-temperature setting process, it melts before the core layer. The melt flows along the yarn surface and penetrates to the intersection of adjacent yarns, forming bonding points after cooling.

[0050] 2. Technical parameters are shown in Table B:

[0051] Table B: Technical Specifications (I)

[0052] Total number of Dan 20D (approximately 22.2 dtex) Core material Low melting point Lycra spandex Skin material Low melting point TPU or CoPA Skin melting point Approximately 120-140℃ Core softening point Approximately 160-180℃ Elongation at break ≥400% Elastic recovery rate (200% elongation) ≥95%

[0053] 3. The reasons for choosing 20D ultra-fine denier hot-melt spandex yarn as jacquard yarn are as follows: ① Fine base structure: 20D (approximately 22.2 dtex) is one of the finest spandex specifications currently available commercially. Ultra-fine denier yarn can be woven into an extremely fine and uniform base structure, making the fabric soft to the touch and lightweight. ② Hot-melt bonding function: The outer layer is melted and bonded at the setting temperature, achieving arbitrary cutting performance without the need for additional adhesives. ③ Jacquard compatibility: The fineness of 20D makes the load on each jacquard guide needle lighter, and it is not easy to break the yarn under high-speed weaving conditions (approximately 1100 r / min), ensuring the accuracy and stability of jacquard weaving.

[0054] (II) Spandex yarn – 210D Lycra spandex

[0055] 1. Definition and Structure: 210D Lycra spandex is a high-elasticity polyurethane fiber produced by DuPont (now Invista) under the trade name "Lycra®," with a linear density of 210 denier (approximately 233.3 dtex). Its molecular structure consists of low-melting-point, amorphous "soft segments" (polyester or polyether polyol) as the matrix and high-melting-point, crystalline "hard segments" (diisocyanate-chain extender units) blocks. The soft segments provide high elongation (stretchable to 4-7 times the original length), while the hard segments provide high resilience (95%-99% elastic recovery at 200% elongation).

[0056] 2. Technical parameters are shown in Table C:

[0057] Table C: Technical Specifications (II)

[0058] Linear density 210D (approximately 233.3 dtex) Elongation at break 500%-700% Elastic recovery rate (200% elongation) 95%-99% Elastic modulus (200% elongation) Approximately 0.08g / day Fracture strength 0.5-0.8 cN / dtex softening temperature Above 200°C

[0059] 3. The reasons for choosing 210D coarse denier Lycra spandex are as follows: ① High elastic recovery: According to Hooke's Law F=k×ΔL, under the same elastic elongation, the greater the linear density of spandex (i.e., the larger the effective cross-sectional area), the greater its elastic recovery force F. 210D spandex has about 3-5 times the recovery force of conventional 40D-70D spandex, providing stronger rebound force after the fabric is stretched. ② Matching with lateral displacement: When the lateral displacement of spandex increases from 1 stitch to 3 stitches, the width across the fabric increases by about 3 times, increasing the effective elastic travel. To ensure that spandex can still provide sufficient recovery force in such a large elastic travel, coarse denier spandex must be used. The 210D specification has been experimentally verified as the optimal balance point—too large (such as 420D) results in a stiff feel and excessive areal density; too small (such as 70D) results in insufficient elastic recovery force. ③ Durability: Coarse denier spandex has better fatigue resistance than fine denier spandex. According to literature data, 210D spandex can withstand more than 1 million cycles without breaking when subjected to tensile shrinkage fatigue tests at a frequency of 220 cycles / minute within the elongation range of 30%-300%, ensuring the long-life elasticity of the fabric.

[0060] (III) Combed yarn – 70D nylon or 70D polyester

[0061] 1. Definition and Structure: Patterned yarn is used to create designs on lace fabrics. It is made of standard 70D nylon 6 filament (PA6) or 70D polyester filament (PET), both of which are fully drawn yarn (FDY) or pre-oriented yarn (POY) stretched textured yarn (DTY). The fiber cross-section is circular or triangular (glossy yarn), and semi-dull or fully dull varieties can be selected according to design requirements.

[0062] 2. The reasons for choosing 70D nylon or polyester are as follows: ① Pattern expressiveness: 70D has a moderate linear density, which can form clear and three-dimensional pattern outlines in warp-knitted jacquard without making the fabric too heavy due to excessive coarseness. ② Functional independence: The combed yarn only undertakes the function of pattern expression, and is completely decoupled from the elastic function and heat-melt bonding function. Therefore, the freedom of pattern design is not limited by elasticity requirements, and the color, luster, and dyeing process of the combed yarn can be optimized independently. ③ Material flexibility: Nylon is suitable for acid dyeing (bright colors, complete color spectrum), while polyester is suitable for disperse dyeing (good color fastness, wash and sun resistance). The choice can be made flexibly according to the specific color and fastness requirements of the product.

[0063] Step Two: Configuration of the Head and Shoulders

[0064] Jacquard yarn uses two sets of 303 type head full-thread configurations, with 20 denier Lycra hot-melt spandex loose yarn threaded through each needle position of each jacquard working thread. Elastic reinforcement yarn uses two sets of 303 type head configurations, each corresponding to one of the two spandex working threads. Combed yarn uses one set of 303 type head full-thread configurations.

[0065] It should be noted that a beam (warp beam) is a winding device on a warp knitting machine used to carry the warp yarns. This invention uses a type 303 beam (i.e., a standard warp knitting machine beam with a diameter of approximately 30 inches and a flange spacing of approximately 3 inches), with the specific configuration shown in Table D below:

[0066] Table D: Pan Head Configuration Table

[0067] 20D hot melt spandex loose yarn (jacca yarn) 2 sets Type 303 Full wear 210D Lycra Spandex (Spandex Yarn) 2 sets Type 303 According to the air-penetration scheme 70D Nylon / Polyester (Combed Yarn) 1 set Type 303 Full wear

[0068] Step 3: Warping – Warping the 210 denier Lycra spandex with a pre-stretch rate of 60% to keep the spandex in a pre-stretched state during weaving.

[0069] The pre-stretch ratio is defined as: PR = (L actual -L relaxed ) / L relaxed ×100%, where L actual L represents the actual yarn feed length of the spandex during warping. relaxedThis represents the natural relaxation length of spandex. After 60% pre-stretching, the actual linear density of spandex is D. actual =210D / (1+0.6)=131.25D.

[0070] This pre-stretch ratio allows the spandex to maintain appropriate tension (approximately 5-7g) during weaving, providing sufficient tension to ensure stable loop formation while also allowing enough elasticity for subsequent stretching.

[0071] Step 4: Yarn Threading – On the Karl Mayer RSJ 5 / 1 EL warp-knitting jacquard machine, fully thread the jacquard yarn onto both jacquard work lines. Thread the comb yarn onto the comb work line according to the preset pattern. Configure the elastic reinforcing yarn through the two spandex work lines using a mirrored cross-threading method. Specifically: the first spandex work line uses a one-through-one-empty threading method, i.e., threading 210 denier Lycra spandex into odd-numbered needle positions and leaving it empty into even-numbered needle positions; the second spandex work line uses a one-empty-one-through threading method, i.e., threading 210 denier Lycra spandex into even-numbered needle positions and leaving it empty into odd-numbered needle positions. The threading positions of the two work lines are completely complementary; where there is yarn on the first spandex work line, the second spandex work line is empty, and vice versa, so that the spandex yarns on the two work lines are arranged alternately in space.

[0072] It should be noted that:

[0073] (a) RSJ 5 / 1 EL working line numbering and function allocation

[0074] The RSJ 5 / 1 EL model has 5 guide bars (GB), numbered GB1-GB5, where GB1-GB4 are floor combs / pattern combs, and GB5 is a spandex comb. However, in the technical solution of this invention, the guide bars are redistributed according to functional requirements as shown in Table E below:

[0075] Table E: Workline Assignment Table

[0076] GB1 Jacquard Working Line 1 20D hot melt spandex empty yarn Full wear 303 Headband x1 (Jacques) GB2 Jacquard Working Line 2 20D hot melt spandex empty yarn Full wear 303 Headband x1 (Jacques) GB3 Flower comb working line 1 70D nylon or polyester Design by pattern 303 Hair Comb x1 (Flower Comb) GB4 Comb working line 2 (spare) 70D nylon or polyester Design by pattern Shared or independent with GB3 GB5 Spandex production line 1 (line 5) 210D Lycra Spandex One through and one empty 303 coiled head x 1 (spandex) GB6 Spandex production line 2 (line 6) 210D Lycra Spandex One empty and one through 303 coiled head x 1 (spandex)

[0077] Note: The standard configuration of RSJ 5 / 1 EL is 5 working lines, but in this solution, by merging the comb working lines or utilizing the multi-station function of the Jacquard system, it is actually equivalent to using 6 working lines (GB5 and GB6 correspond to two sets of spandex coil heads respectively).

[0078] (II) Detailed explanation of the mirror cross-threading method of spandex

[0079] GB5 (5th working line) - "One thread, one empty thread" yarn threading: Starting from the 1st needle of the total number of needles in machine size E24, thread 210D Lycra spandex into the odd-numbered needle positions (1, 3, 5, 7, ..., 3215), and do not thread yarn into the even-numbered needle positions (2, 4, 6, 8, ..., 3216) (empty thread).

[0080] GB6 (6th working line) - "One blank, one thread" yarn threading: Starting from the 1st needle position, thread 210D Lycra spandex at even-numbered needle positions (2, 4, 6, 8, ..., 3216), and do not thread yarn at odd-numbered needle positions (1, 3, 5, 7, ..., 3215) (blank thread).

[0081] The geometric meaning and physical principle of this threading method are as follows:

[0082] ① Complementary Coverage: The threading positions of GB5 and GB6 are completely complementary—the positions where GB5 has yarn are empty in GB6, and vice versa. In the fabric, the distance between each spandex yarn and its adjacent yarn is two stitch lengths (2 × 1.058 mm ≈ 2.116 mm), instead of the one stitch length required for full threading. This avoids direct contact and frictional entanglement between the spandex yarns.

[0083] ② Yarn threading density calculation: The yarn threading density of GB5 = total number of needles / 2 = 3216 / 2 = 1608 spandex yarns; The yarn threading density of GB6 = total number of needles / 2 = 3216 / 2 = 1608 spandex yarns; The total number of spandex yarns = 1608 + 1608 = 3216.

[0084] If full threading is used, the total number of spandex yarns is also 3216 (3216 for GB5 full threading plus 3216 for GB6 full threading, but the total yarn usage is doubled). This invention, through a complementary design of one thread and one gap, maintains the total number of spandex yarns while allowing two spandex yarns to be arranged alternately in space, forming a cross-interlocking elastic network.

[0085] ③ Mirror crossover coefficient N d Determination of: In the subsequent ECC model, the mirror cross density coefficient N d Defined as the multiple factor by which two working lines collaboratively contribute elastic coverage within the same area. Due to the complementary yarn threading of GB5 and GB6, in any horizontal row, each pair of adjacent needle positions (odd + even) contains exactly one spandex yarn, resulting in a total coverage density that is 1 times that of full threading. However, during the positioning process (see step four), the two spandex yarns move in opposite directions, meaning that in each crossing unit, two spandex yarns alternately contribute elasticity. Therefore, N... d =2.

[0086] Step 5: Setting the Spandex Lateral Shift – Determine the lateral shift of the spandex yarn using the Elastic Coverage Coefficient (ECC) model. The physical meaning of ECC is the effective elastic coverage of the spandex yarn per unit area of ​​fabric, defined as: ECC = k × D s ×S t ×L s ×N d ×n c / T d ×ρ c ;

[0087] The meanings of each parameter are as follows: k is the dimensionless coverage conversion factor, determined experimentally, with a value of 6.0 × 10⁻⁶. ﹣5 ;D s The linear density of spandex is taken as 210 denier; S t The horizontal shift gauge is the number of stitches the spandex yarn crosses during knitting, typically 2-3 stitches, and is a parameter to be optimized; L s For spandex yarn feed length, take 12mm / row; N d The mirror cross density coefficient is determined by the mirror cross-threading method of the two spandex working threads, and its value is 2; n c For longitudinal density, the value is 15 rows / cm; T d The aspect ratio is defined as the standard width W. f With the machine's upper width W m The ratio of ρ needs optimization (0.86-1.0); c The coil density ratio is defined as the ratio of the finished coil density to the on-machine coil density, and needs to be optimized (2.0-2.3).

[0088] In ECC, the numerator represents the "potential elastic contribution capacity of spandex"—the greater the linear density, the greater the lateral displacement, the greater the yarn feed length, and the greater the cross density, the greater the potential elasticity. The denominator of ECC represents the "degree of constraint of the fabric structure on the elasticity of spandex"—the greater the setting width ratio and the greater the loop density ratio, the stronger the geometric constraint on spandex in the fabric, and the more limited its elasticity. Therefore, ECC is essentially a "capacity-constraint ratio," and the larger its value, the better the actual elastic performance of the fabric.

[0089] Elastic recovery rate R e The relationship model with ECC is: R e =R0×(1-e ﹣αECC );

[0090] Where R0=98% is the upper limit of the intrinsic elastic recovery rate of 210 denier Lycra spandex (based on material data provided by the spandex supplier and combined with laboratory tests, the present invention takes the value as 98% (the elastic recovery rate of 210D Lycra spandex at 200% elongation is 95%-99%, and the median is 98%)), and α=0.42 is the process adaptation coefficient.

[0091] By solving the elastic restoring rate R e Marginal gain function for ECC: dR e / dECC=R0×α×e ﹣αECC ;

[0092] It should be noted that: ① Monotonically increasing: dR e / dECC=R0×α×e ﹣αECC >0, meaning the larger the ECC, the greater the R e Monotonically increasing. ② Saturation: When ECC→∞, R e →R0, the elastic recovery rate approaches the intrinsic limit of the material. ③ Marginal diminishing returns: d 2 R e / d(ECC) 2 =﹣R0×α 2 ×e ﹣αECC <0, meaning the gain in elastic recovery rate decreases as ECC increases—in the early stages, for every unit increase in ECC, R... e Significant improvement; ECC and R will be further increased in the later stages. e The improvement in elasticity becomes increasingly smaller. These three characteristics indicate that there exists an optimal ECC range: within this range, the return on investment for ECC is the highest; beyond this range, further increasing ECC has a negligible effect on elasticity, but instead increases fabric weight and cost.

[0093] Setting the marginal gain threshold θ = 0.05 × R0, the optimal interval for ECC is determined as ECC. opt ∈[4.8,5.5]. Within this optimal interval, S is determined by reverse calculation using specific process parameters. t =3 needles (please refer to the subsequent calculation and analysis examples for the determination method).

[0094] It should be noted that, in order to find the optimal ECC interval, this invention introduces the concept of "marginal gain"—that is, for every unit increase in ECC, the elastic recovery rate R increases. e Increase in efficiency: MG(ECC) = dR e / dECC=R0×α×e ﹣αECC ;

[0095] A marginal gain threshold θ is set—when the marginal gain is less than θ, it is considered that the benefit of continuing to increase ECC is negligible, and the optimal range has been reached. This invention sets θ = 0.05R0 (that is, when the gain is less than 5% of the intrinsic limit, the increase of ECC is stopped).

[0096] Solve for MG(ECC) = θ: R0 × α × e ﹣αECCmax =0.05R0;α×e ﹣αECCmax =0.05; e ﹣αECCmax =0.05 / α; −αECCmax=ln(0.05 / α); ECC max =-1 / α×ln(0.05 / α); substitute α=0.42: 0.05 / α=0.05 / 0.42≈0.1190; ln(0.1190)≈-2.128; ECC max =﹣1 / 0.42×(﹣2.128)≈5.07;

[0097] At the same time, set a minimum ECC (below this value, elasticity will not meet the standard, R) e <85%):

[0098] By R e =0.98×(1-e ﹣0.42ECC )≥0.85:1-e ﹣0.42ECC ≥0.8673; e ﹣0.42ECC ≤0.1327;-0.42ECC≤ln(0.1327)≈-2.020;ECC min ≥2.020 / 0.42≈4.81;

[0099] Therefore, the optimal ECC interval is:

[0100] ECC opt ∈[4.81,5.07];

[0101] After rounding, and considering process tolerances, determine the ECC. opt ∈[4.8,5.5].

[0102] Step Six: Spandex Positioning

[0103] Set the positions of the two spandex work yarns according to the 3-needle horizontal shift determined in step five. The first spandex work yarn runs in a 1−0 / 3−4 / / pattern, that is, starting from the left starting position, shifting 1 stitch horizontally to the right position, then shifting 3 stitches horizontally to the right across 3 stitch lengths to the further right position, and then returning, repeating the cycle. The second spandex work yarn runs in a 4−3 / 0−1 / / pattern, in the opposite direction to the first spandex work yarn, and is mirror-symmetrical.

[0104] Two working lines form an "X"-shaped cross elastic network structure within a 3-needle transverse span: each cross unit is 3 needle pitches wide (approximately 3.174 mm), and within this unit, two spandex yarns move in opposite directions to form a cross configuration.

[0105] Step 7: Heat setting

[0106] Set the coil density ratio ρ c ≥2.0. Set the setting temperature range to 175℃-200℃ and the setting time to 30-60 seconds for high-temperature setting treatment.

[0107] The lower limit of the setting temperature is determined by the Arrhenius equation. The diffusion rate constant k(T) of the hot-melt component is related to the temperature T by: k(T) = A × exp(-E a / RT); where A = 2.5 × 10 8 s ﹣1 E is a pre-exponential factor. a =85 kJ / mol is the activation energy of the hot-melt component, and R=8.314 J / (mol•K) is the ideal gas constant. Adhesion strength factor S b The relationship between S and the setting time t and temperature T is: b (t,T)=N0×[1-exp(﹣A×t×exp(﹣E a / RT))];

[0108] Set the adhesive strength threshold S b ≥0.85N0 (i.e., at least 85% of the nodes that can form adhesive bonds are effectively bonded), and the minimum setting temperature is 175℃ under the condition of setting time t=30−60s.

[0109] During the high-temperature setting process, the heat-melting component of the outer layer of the 20 denier Lycra heat-melting spandex hollow yarn melts at 175℃-200℃. The melt flows along the yarn surface and penetrates to the intersections of the jacquard yarn, combed yarn, and elastic reinforcing yarn under capillary action. After cooling, the melt solidifies to form bonding points, fixing the yarns at the intersections.

[0110] Standard width W f With the machine's upper width W m The ratio is determined by the linkage control formula: W f / W m =(ρ c / ρ c,ref )×[1 / 1+γ(S t -1)];

[0111] Where ρ c,ref =2.0 is the reference coil density ratio, and γ=0.08 is the lateral displacement correction factor. When using a two-width fabric scheme, ρc =2.3, S t =3, calculated as W f / W m ≈0.99; When using a one-piece fabric cutting scheme, ρ c =2.0, S t =3, calculated as W f / W m ≈0.86.

[0112] Step 8: Post-processing

[0113] After shaping, the fabric undergoes dyeing, washing, drying and other finishing processes to obtain the final high-elasticity four-way stretch lace composite fabric.

[0114] Example 1: Two-width fabric cutting scheme

[0115] This embodiment uses a Karl Mayer RSJ 5 / 1 EL warp knitting jacquard machine, model number E24, with a working width of 134 inches and a total of 3216 needles.

[0116] Yarn selection: Jacquard yarn is 20 denier Lycra hot melt spandex air-wrapped yarn, elastic reinforcing yarn is 210 denier Lycra spandex, and combed yarn is 70 denier nylon 6 filament.

[0117] Headwear configuration: Two full-length 303 headwear pieces in jacquard yarn, two full-length 303 headwear pieces in spandex yarn, and one full-length 303 headwear piece in combed yarn.

[0118] Warping: 210 denier spandex is warped with a pre-stretch rate of 60%.

[0119] Wearing gauze:

[0120] Jacquard working line: Fully threaded with 20 denier hot-melt spandex open-face yarn;

[0121] The comb working line: 70 denier nylon is threaded into the pre-set pattern;

[0122] First spandex working line: one thread and one loop thread 210 denier Lycra spandex (odd number needle positions thread the yarn, even number needle positions loop the yarn).

[0123] Second spandex working line: one pass and one thread pass 210 denier Lycra spandex (even-numbered needle positions pass yarn, odd-numbered needle positions pass yarn).

[0124] Lateral displacement setting: Based on the ECC model, set ρ c =2.3, S is determined by reverse calculation from the optimal ECC interval. t =3 stitches.

[0125] Spandex positioning:

[0126] First spandex working line positioning: 1−0 / 3−4 / / ;

[0127] The second spandex working line is positioned as follows: 4−3 / 0−1 / / , mirroring the first working line.

[0128] Yarn feed length: L s =12mm / row.

[0129] Onboard longitudinal density: set to 15 rows / cm.

[0130] Setting parameters: Setting temperature: 185℃ (within the range of 175℃-200℃); Setting time: 45 seconds; Coil density ratio ρ c =2.3; Width ratio: determined by the linkage control formula W f / W m = (2.3 / 2.0) × [1 / 1 + 0.08 × 2] ≈ 0.99, that is, W f ≈W m .

[0131] During the setting process, the 20 denier Lycra hot melt spandex hollow yarn skin melts at 185℃. The melt flows along the yarn surface and forms bonding points at the intersection of Jacquard yarn, combed yarn and elastic reinforcing yarn. After cooling, it is fixed.

[0132] Finishing: The shaped fabric is dyed (70 denier nylon is dyed with acid dye), washed and dried to obtain the finished product.

[0133] The fabric performance test results are shown in Table F below:

[0134] Table F: Fabric Performance Test Results (I)

[0135] Longitudinal elastic stretch ratio GB / T 3923.1-2013 1:2.6 Lateral elastic stretch ratio GB / T 3923.1-2013 1:1.9 Longitudinal elastic recovery rate GB / T 3923.1-2013 93.2% Lateral elastic recovery rate GB / T 3923.1-2013 91.5% Arbitrary cutting performance (edge ​​fraying length) Rub 100 times after cutting 0mm (no loosening) Fabric weight Weighing method 165g / m² feel Subjective rating soft

[0136] Example 2: Fabric cutting scheme (higher elasticity)

[0137] This embodiment is basically the same as embodiment 1, except that it adopts a one-piece fabric cutting method to obtain higher elasticity.

[0138] The yarn selection, warp head configuration, warping, and threading method are all the same as in Example 1. Different parameter settings are as follows: loop density ratio ρ c =2.0; Standard width ratio: W f / W m = (2.0 / 2.0) × [1 / 1 + 0.08 × 2] ≈ 0.86, that is, W f ≈0.86W m During the setting process, the fabric shrinks by approximately 14% laterally; setting temperature: 180℃; setting time: 40 seconds.

[0139] The fabric performance test results are shown in Table G:

[0140] Table G: Fabric Performance Test Results (II)

[0141] Longitudinal elastic stretch ratio 1:2.8 Lateral elastic stretch ratio 1:2.0 Longitudinal elastic recovery rate 95.8% Lateral elastic recovery rate 94.2% Arbitrary performance No disintegration Fabric weight 148g / m²

[0142] Example 3: Polyester combed yarn scheme

[0143] This embodiment is basically the same as Embodiment 1, except that the combed yarn uses 70 denier polyester filament (with bright yarn in triangular cross section) instead of 70 denier nylon.

[0144] The dyeing process was adjusted accordingly: polyester was dyed with disperse dyes under high temperature and high pressure conditions, with a dyeing temperature of approximately 130℃. Since the setting process was carried out after dyeing, and the setting temperature was 185℃, the polyester combed yarn did not suffer heat damage during the setting process.

[0145] The fabric properties are comparable to those of Example 1, but the pattern luster and color fastness are different—the polyester triangular section yarn has a bright luster, and the color fastness of disperse dyes is better than that of acid dyes on nylon.

[0146] Example 4: ECC Model Parameter Validation Experiment

[0147] To verify the accuracy of the ECC model, this embodiment designed a series of fabric samples with different ECC values ​​for elasticity performance testing.

[0148] Fixed parameter: D s =210D, L s =12mm / row, N d =2,n c =15 rows / cm.

[0149] Variable parameter: S t Take 1, 2, 3, and 4 stitches respectively; ρ c Take values ​​of 1.5, 2.0, 2.3, and 2.5 respectively; T d Adjust accordingly according to the linkage formula.

[0150] A total of 16 samples were obtained in the experiment, and their elastic recovery rate R was tested respectively. e And compare it with the predicted value of the ECC model.

[0151] Experimental results show that the average deviation between the predicted and measured values ​​of the ECC model is 2.3%, and the maximum deviation does not exceed 5.0%. When S t =3 needles, ρ c When R = 2.0 − 2.3, ECC is in the optimal range, and R e Reaching 90%-96%. When S t When there is 1 needle, the ECC value is approximately 1.5-2.0, R eOnly 70%-80%, indicating insufficient elasticity. When S... t When there are 4 pins, the ECC value is approximately 7-9, R e It is approximately 97%-98%, but the fabric weight increases by about 20%, the feel is stiffer, and the cost performance decreases.

[0152] To better understand the technical solution of the present invention, the following specific calculation and analysis process is provided for reference, taking the scheme of cutting two pieces of fabric as an example.

[0153] 1. Overview of Implementation Examples

[0154] This embodiment uses a Karl Mayer RSJ 5 / 1 EL warp-knitting jacquard machine, model E24, with a working width of 134 inches (3403.6 mm) and a total of 3216 stitches, to produce a high-elasticity four-way stretch lace composite fabric with two open widths. The target is: a longitudinal elastic stretch ratio of ≥1:2.6, a transverse elastic stretch ratio of ≥1:1.9, and an elastic recovery rate ≥90%.

[0155] 2. Yarn selection and parameters are shown in Table 1 below:

[0156] Table 1: Yarn Selection and Parameter Table

[0157] Jacques 20D Lycra hot melt spandex empty yarn 22.2 dtex Invista Lycra® T162 Series The outer layer of TPU has a melting point of 125℃, the core layer has a softening point of 170℃, an elongation at break of 450%, and an elastic recovery rate of 96% (200% elongation). Elastic reinforced yarn 210D Lycra Spandex 233.3 dtex Invista Lycra® 210D Elongation at break 600%, elastic recovery 98% (200% elongation), elastic modulus 0.08 g / denier, softening point >200℃ Flower comb yarn 70D Nylon 6 FDY 77.8 dtex Li Peng Tensile strength 4.5 cN / dtex, elongation at break 35%, melting point 220℃

[0158] Explanation of linear density units: Denier (D) is defined as the mass (in grams) of 9000 meters of fiber. Tetra (tex) is defined as the mass (in grams) of 1000 meters of fiber. Conversion: 1D = 1 / 9 tex, i.e., 20D = 22.2 dtex (dectex, i.e., 1 / 10 tex).

[0159] 3. Calculation of warping parameters

[0160] The pre-stretch rate (PR) of spandex is 60%, meaning that spandex is stretched to 1.6 times its original length during warping.

[0161] Calculation of the actual linear density of spandex during warping: D actual =D nominal / (1+PR)=210D / (1+0.6)=210 / 1.6=131.25D;

[0162] Converted to tex: 131.25D × 1 / 9 = 14.58 tex;

[0163] Warping tension calculation:

[0164] The elastic modulus of spandex is approximately 0.08 g / denier. At 60% elongation, the tension of a single spandex yarn is: F tension =Emodulus ×D nominal ×ε=0.08 g / dan ×210D ×0.6=10.08 g;

[0165] That is, the tension of each spandex yarn during warping is approximately 10 grams of force. The total tension of 1608 spandex yarns (one threaded and one open) is approximately 16 kgf.

[0166] 4. Method of threading the yarn

[0167] Total number of stitches determined: N total =W m ×E = 134 inches × 24 pins / inch = 3216 pins;

[0168] Spandex yarn weaving:

[0169] First spandex working line (GB5): odd-numbered needle positions (1, 3, 5, ..., 3215) for yarn threading, totaling 1608 spandex yarns;

[0170] Second spandex working line (GB6): even-numbered needle positions (2, 4, 6, ..., 3216) for yarn threading, totaling 1608 spandex yarns;

[0171] Effective yarn threading density per work line: 1608 yarns / 134 inches = 12 yarns / inch (i.e., half-size configuration);

[0172] However, by complementing each other with two working lines, the equivalent full coverage is achieved: 1608 + 1608 = 3216 roots.

[0173] Jacques wearing a veil:

[0174] Two Jacquard work lines (GB1 and GB2) each have 3216 yarns fully threaded, totaling 6432 yarns of 20D hot melt spandex empty yarn.

[0175] Flower comb and gauze threading:

[0176] Thread 70D nylon yarn into the yarn according to the preset pattern, with a total of 3216 yarns when fully threaded.

[0177] 5. ECC model calculation of spandex lateral displacement

[0178] 5.1 Determination of the optimal ECC interval

[0179] According to the ECC model of the present invention: ECC = k × D s ×S t ×L s ×N d ×n c / T d ×ρ c ;

[0180] Elastic recovery rate model: R e =R0×(1-e ﹣α×ECC );

[0181] Given parameters: R0 = 98% = 0.98; α = 0.42; k = 6.0 × 10⁻⁶ ﹣5 ;D s =210D;L s =12 mm / row; N d =2; n c =15 rows / cm;

[0182] Solve for the optimal ECC interval:

[0183] Marginal gain function: MG(ECC) = dR e / dECC=R0×α×e ﹣α×ECC =0.98×0.42×e ﹣0.42×ECC MG(ECC) = 0.4116 × e ﹣0.42×ECC ;

[0184] Set the marginal gain threshold θ = 0.05 × R0 = 0.05 × 0.98 = 0.049;

[0185] Let MG (ECC) max )=θ:

[0186] 0.4116×e ﹣0.42×ECCmax =0.049; e ﹣0.42ECCmax =0.049 / 0.4116=0.11905; -0.42×ECC max =ln(0.11905)=﹣2.128;ECC max =2.128 / 0.42=5.067;

[0187] Set minimum ECC (elastic recovery rate not less than 85%): R e =0.98×(1-e ﹣0.42ECCmin )≥0.85; 1-e ﹣0.42ECCmin ≥0.85 / 0.98=0.86735; e ﹣0.42ECCmin ≤1-0.86735=0.13265; -0.42ECC min ≤ln(0.13265)=﹣2.020;ECC min ≥2.020 / 0.42=4.810;

[0188] Therefore, the optimal interval for ECC is: ECC opt ∈[4.810,5.067];

[0189] Considering process tolerance (±5%), rounded to: ECCopt ∈[4.8,5.5];

[0190] 5.2 Verify the elastic recovery rate corresponding to the optimal ECC interval:

[0191] In ECC min =4.8:

[0192] R e =0.98×(1-e ﹣0.42×4.8 ) = 0.98 × (1 - e ﹣2.016 =0.98×(1-0.1331)=0.98×0.8669=0.8496≈85.0%;

[0193] In ECC max =5.5:

[0194] R e =0.98×(1-e ﹣0.42×5.5 ) = 0.98 × (1 - e ﹣2.31 =0.98×(1-0.0993)=0.98×0.9007=0.8827≈88.3%;

[0195] That is, the elastic recovery rate range corresponding to this ECC interval is 85.0%-88.3%.

[0196] 5.3 Setting the target elastic recovery rate in this embodiment

[0197] This embodiment requires the fabric's elastic recovery rate to be ≥90%. From the above calculations, it can be seen that when ECC=5.5, R... e The ECC value is approximately 88.3%, which is below 90%. Therefore, further adjustments to other parameters are needed to improve the ECC value.

[0198] Reset the ECC target value: Let R e =90%, therefore, ECC is calculated as: 0.90 = 0.98 × (1 - e ﹣0.42ECCtarget );1-e ﹣0.42ECCtarget =0.90 / 0.98=0.91837; e ﹣0.42ECCtarget =0.08163; -0.42ECC target =ln(0.08163)=﹣2.505;ECC target =2.505 / 0.42=5.964;

[0199] 5.4 Deducing the lateral displacement S from the ECC target t

[0200] This embodiment describes a two-width fabric cutting scheme, with ρ set as the dimensional standard. c =2.3.

[0201] First, T is calculated using the fixed width linkage control formula. d :W f / W m =(ρ c / ρ c,ref )×[1 / 1+γ(S t -1)];

[0202] Because of T d =W f / W m And the formula contains S t And S t Since these are variables that need to be determined, iterative solutions or prior estimations are required.

[0203] Method 1: Iterative solution

[0204] Let S t =3 needles: T d =(2.3 / 2.0)×[1 / 1+0.08×(3-1)]=1.15×1 / 1.16=1.15×0.86207=0.99138;

[0205] Substituting into the ECC formula: ECC = 6.0 × 10 ﹣5 ×210×3×12×2×15 / 0.99138×2.3;

[0206] Molecular calculation: 210×3×12×2×15=210×3=630, 630×12=7560, 7560×2=15120, 15120×15=226800;

[0207] Calculate the denominator: 0.99138 × 2.3 = 2.280174;

[0208] ECC=6.0×10 ﹣5 ×226800 / 2.280174; 226800 / 2.280174=99469.4;

[0209] ECC=6.0×10 ﹣5 ×99469.4=5.9682;

[0210] Verify the ECC target: ECC = 5.9682 ≈ ECC target =5.964, a match.

[0211] Calculate the corresponding elastic recovery rate: R e =0.98×(1-e ﹣0.42×5.9682 ) = 0.98 × (1 - e ﹣2.5066 );e ﹣2.5066 =0.08159; Re =0.98×(1-0.08159)=0.98×0.91841=0.9000=90.0%;

[0212] Method 2: Using S t =2-needle verification (comparison)

[0213] Let S t =2 stitches, first calculate T d :T d =(2.3 / 2.0)×[1 / 1+0.08×(2-1)]=1.15×1 / 1.08=1.15×0.92593=1.06482;

[0214] Substituting into the ECC formula: ECC = 6.0 × 10 ﹣5 ×210×2×12×2×15 / 1.06482×2.3;

[0215] Molecules: 210×2=420, 420×12=5040, 5040×2=10080, 10080×15=151200;

[0216] Denominator: 1.06482 × 2.3 = 2.449086;

[0217] ECC=6.0×10 ﹣5 ×151200 / 2.449086=6.0×10 ﹣5 ×61736.0=3.7042;

[0218] Corresponding elastic recovery rate: R e =0.98×(1-e ﹣0.42×3.7042 ) = 0.98 × (1 - e ﹣1.5558 );e ﹣1.5558 =0.2108; R e =0.98×(1-0.2108)=0.98×0.7892=0.7734=77.3%;

[0219] The fact that it is far below the target requirement of 90% verifies S t =2 needles lack elasticity.

[0220] Method 3: Using S t =4-pin verification (comparison)

[0221] Let S t =4 stitches, first calculate T d :T d =(2.3 / 2.0)×[1 / 1+0.08×(4-1)]=1.15×1 / 1.24=1.15×0.80645=0.92742;

[0222] Substituting into the ECC formula: ECC = 6.0 × 10 ﹣5 ×210×4×12×2×15 / 0.92742×2.3;

[0223] Molecules: 210×4=840, 840×12=10080, 10080×2=20160, 20160×15=302400;

[0224] Denominator: 0.92742 × 2.3 = 2.13307;

[0225] ECC=6.0×10 ﹣5 ×302400 / 2.13307=6.0×10 ﹣5 ×141768.7=8.5061;

[0226] Corresponding elastic recovery rate: R e =0.98×(1-e ﹣0.42×8.5061 ) = 0.98 × (1 - e ﹣3.5726 );e ﹣3.5726 =0.0281; R e =0.98×(1-0.0281)=0.98×0.9719=0.9525=95.3%;

[0227] Although the elastic recovery rate reaches 95.3%, ECC = 8.5061 is far beyond the optimal range [4.81, 5.07], and the marginal gain MG(ECC) = 0.4116 × e ﹣0.42×8.5061 =0.4116×0.0281=0.0116, which is much smaller than the threshold of 0.049, indicating that the elasticity improvement is very low. At the same time, increasing the transverse shift to 4 stitches means that the coverage width of the spandex yarn in the fabric increases to 4 stitches (about 4.23mm), the fabric weight increases by about 15%, the hand feel becomes stiffer, and the cost performance decreases.

[0228] Conclusion: S t =3 needles is the optimal choice.

[0229] 6. Spandex positioning settings

[0230] First spandex working line (GB5) routing: 1−0 / 3−4 / /

[0231] Explanation: In the first row, the spandex yarn moves from position 1 to position 0 (shifting 1 stitch to the left); in the second row, the spandex yarn moves from position 0 to position 3 (shifting 3 stitches to the right); in the third row, the spandex yarn moves from position 3 to position 4 (shifting 1 stitch to the right); in the fourth row, the spandex yarn moves from position 4 back to position 1 (shifting 3 stitches to the left). The cycle consists of 4 rows.

[0232] Second spandex working line (GB6) routing: 4−3 / 0−1 / /

[0233] Explanation: Mirror symmetry with GB5. In the first row, the spandex yarn moves from position 4 to position 3 (shifting 1 stitch to the left); in the second row, it moves from position 3 to position 0 (shifting 3 stitches to the left); in the third row, it moves from position 0 to position 1 (shifting 1 stitch to the right); in the fourth row, it moves from position 1 to position 4 (shifting 3 stitches to the right). The cycle is 4 rows.

[0234] Cross-network structure parameters: Lateral coverage width of a single spandex yarn: 3 stitches × 1.058 mm / stitches = 3.174 mm; Width of each "X"-shaped cross unit: 3 stitches (3.174 mm); Crossing angle of spandex yarn within each "X"-shaped cross unit: Through geometric calculation, during the lateral shift of 3 stitches, the spandex yarn shifts 3.174 mm laterally and 1 row's height longitudinally (approximately 1 / n). c =1 / 15 cm=0.667 mm). The crossing angle θ satisfies: tan(θ / 2)=longitudinal displacement / 0.5 lateral displacement=0.667 / 3.174×0.5=0.667 / 1.587=0.420 θ / 2=arctan(0.420)=22.8° θ=45.6°, that is, the included angle between the two crossed spandex yarns is approximately 45.6°. This angle makes the elastic force more balanced in the warp and weft directions, which is conducive to achieving a four-way stretch effect.

[0235] 7. Calculation of density and shaping parameters

[0236] 7.1 Onboard density setting: Onboard longitudinal density (n c = 15 rows / cm Machine row density (n) w = 24 warp rows / cm (directly determined by machine size E24); Number of stitches per square centimeter of knitted fabric on the machine: 15 × 24 = 360 stitches / cm 2 ;

[0237] 7.2 Finished Product Density

[0238] Set ρ c =2.3: Finished product longitudinal density = Machine longitudinal density × ρ c =15×2.3=34.5 rows / cm; Finished product horizontal density = machine horizontal density × ρ c 0.5 (The effect of meridional contraction on latitudinal contraction, calculated using an empirical coefficient of 0.7): 24×(1+0.7×(2.3-1))=24×1.91≈45.8 longitudinal rows / cm;

[0239] 7.3 Standard Width: Machine Width: W m=134 inches = 3403.6 mm; Standard width: W f =T d ×W m =0.99138×3403.6=3374.2 mm; Width shrinkage during shaping: 3403.6−3374.2=29.4 mm, shrinkage rate is about 0.86%.

[0240] 7.4 Arrhenius Equation Calculation of Shaping Temperature

[0241] Adhesion kinetics of hot melt skin during the setting process: S b (t,T)=N0×[1-exp(﹣A×t×exp(﹣E a / RT))];

[0242] Given parameter: A = 2.5 × 10 8 s ﹣1 E a =85 kJ / mol=85000 J / mol; R=8.314 J / (mol·K);

[0243] N0 is the total number of nodes that can form adhesive bonds.

[0244] The shaping time in this embodiment is set to t = 45 s, and S is required to be... b ≥0.85N0.

[0245] Solve for the minimum setting temperature:

[0246] By S b (t,T)≥0.85N0:1-exp(﹣A×t×exp(﹣E a / RT))≥0.85;exp(﹣A×t×exp(﹣E a / RT))≤0.15;A×t×exp(﹣E a / RT)≥﹣ln(0.15)=1.8971;exp(﹣E a / RT)≥1.8971 / A×t=1.8971 / 2.5×10 8 ×45=1.8971 / 1.125×10 10 =1.6863×10 ﹣10 ;﹣E a / RT≥ln(1.6863×10 ﹣10 E = -22.504; a / RT≤22.504;T≥E a / 22.504×R=85000 / 22.504×8.314=85000 / 187.105=454.3K; Tmin =454.3 K - 273.15 = 181.2℃;

[0247] The adhesive strength verification at different setting temperatures is shown in Table 2 below:

[0248] Table 2: Adhesion strength verification table at different setting temperatures

[0249] Setting temperature T (°C) Absolute temperature T (K) <![CDATA[exp(﹣E a / RT)]]> <![CDATA[﹣Atexp(﹣E a / RT)]]> <![CDATA[S b / N0]]> 170 443.15 <![CDATA[1.029×10 ﹣10 ]]> <![CDATA[﹣2.5×10 8 ×45×1.029×10 ﹣10 =﹣1.158]]> <![CDATA[1-e ﹣1.158 =0.686]]> 175 448.15 <![CDATA[1.474×10 ﹣10 ]]> <![CDATA[﹣2.5×10 8 ×45×1.474×10 ﹣10 =﹣1.658]]> <![CDATA[1-e ﹣1.658 =0.809 <!-- 15 -->]]> 180 453.15 <![CDATA[2.088×10 ﹣10 ]]> <![CDATA[﹣2.5×10 8 ×45×2.088×10 ﹣10 =﹣2.349]]> <![CDATA[1-e ﹣2.349 =0.905]]> 185 458.15 <![CDATA[2.926×10 ﹣10 ]]> <![CDATA[﹣2.5×10 8 ×45×2.926×10 ﹣10 =﹣3.292]]> <![CDATA[1-e ﹣3.292 =0.963]]> 190 463.15 <![CDATA[4.057×10 ﹣10 ]]> <![CDATA[﹣2.5×10 8 ×45×4.057×10 ﹣10 =﹣4.564]]> <![CDATA[1-e ﹣4.564 =0.990]]> 195 468.15 <![CDATA[5.569×10 ﹣10 ]]> <![CDATA[﹣2.5×10 8 ×45×5.569×10 ﹣10 =﹣6.265]]> <![CDATA[1-e ﹣6.265 =0.998]]> 200 473.15 <![CDATA[7.571×10 ﹣10 ]]> <![CDATA[﹣2.5×10 8 ×45×7.571×10 ﹣10 =﹣8.517]]> <![CDATA[1-e ﹣8.517 =1.000]]>

[0250] As shown in the table above, under the condition of t=45s, the minimum setting temperature is 181.2℃ (calculated value), while the actual process temperature is taken as 185℃. At this time, S b / N0=0.963, meaning that 96.3% of the adhesive nodes have formed effective adhesion, indicating sufficient adhesion.

[0251] Meanwhile, it is necessary to ensure that the setting temperature does not exceed the elastic damage temperature of spandex. The softening point of 210D Lycra spandex is >200℃. Short-term treatment at 185℃ does not significantly change the molecular structure of spandex. According to relevant research, after treatment at 180℃ for 45 seconds, the tensile strength of spandex increases by approximately 5%, while the elastic recovery rate decreases by approximately 2%, which is still within an acceptable range.

[0252] 7.5 Calculation of hot-melt spandex bonding joints

[0253] At ECC=5.97, ρ c Under the condition of 2.3, the total number of yarn intersections per square centimeter of fabric is approximately: Intersection of combed yarn and jacquard yarn = Finished horizontal density × Finished vertical density × Number of combed yarn working threads = 45.8 × 34.5 × 1 ≈ 1580 nodes / cm²; Intersection of spandex and jacquard yarn = Finished horizontal density / 2 (one thread through one open) × Finished vertical density × 2 (two spandex yarns) × 2 (each spandex yarn intersects with at least one jacquard yarn per horizontal row) ≈ 22.9 × 34.5 × 2 × 2 ≈ 3160 ≈ 22.9 × 34.5 × 2 × 2 ≈ 3160 nodes / cm²; Total number of nodes N0 ≈ 1580 + 3160 = 4740 nodes / cm² 2 ; in S b With N0 = 0.963, the effective number of bonded nodes is approximately 4740 × 0.963 ≈ 4565 nodes / cm. 2 Average adhesive spacing: (1 / 4565) 0.5 ≈0.148 cm≈1.48 mm; that is, there is an effective bonding point every 1.48 mm, which is sufficient to prevent the yarn from slipping off the cut edge.

[0254] 8. Calculation of yarn feed length and spandex content

[0255] 8.1 Length of each spandex yarn fed per row: L s=12 mm / row;

[0256] 8.2 Total spandex usage per square meter of fabric: Number of rows per square meter = Finished warp density × 100 = 34.5 × 100 = 3450 rows / m²; Total length of each spandex yarn per square meter = 3450 × 12 mm = 41400 mm = 41.4 m; Linear density of a single spandex yarn (including the actual value after pre-stretching): 131.25D = 14.58 tex = 14.58 g / 1000m; Mass contribution of a single spandex yarn: 41.4 m × 14.58 g / 1000 m = 0.604 g / m²; Total number of spandex yarns (two working lines effective): 3216 yarns (one threaded and one open + one open and one threaded).

[0257] However, it should be noted that spandex yarn is woven continuously along the entire length of the fabric, and the mass calculation per unit area also needs to consider the longitudinal distribution density of each yarn. A more direct method:

[0258] Mass of spandex per square meter = Total number of spandex threads × Length of yarn fed per row × Number of rows / m² × Linear density = 3216 threads × 0.012m / row × 3450 rows / m² × (14.58 × 10) ﹣6 ) kg / m= 3216×0.012×3450×14.58×10 ﹣6 = 3216 × 3450 = 11095200; multiplied by 0.012 = 133,142.4; multiplied by 14.58 × 10 ﹣6 =1.941 kg / m²;

[0259] However, this calculation is incorrect—the above calculation assumes that each spandex yarn is fed 12mm of yarn in each row, but in reality, one spandex yarn only weaves one loop in one row, and the yarn length consumed by each loop is approximately 3 times the stitch length (considering loop geometry), approximately 3 × 1.058mm = 3.174mm. Here, L... s =12mm / column is the total yarn feed for the entire work line (all 3216 spandex yarns).

[0260] Correct calculation: Total yarn feed length per spandex workline per row = 12m / row (total yarn feed at the head); Total yarn feed length of two spandex worklines per row = 2 × 12 = 24m / row; Total number of rows per square meter = 3450 rows / m²; Total spandex yarn feed length per square meter = 24 × 3450 = 82800 m / m²; Spandex linear density (after pre-drafting): 14.58g / 1000m; Spandex mass per square meter = 82800 × 14.58 / 1000 = 1207.2 g / m²;

[0261] This value is significantly too large, indicating that "12mm / row" is not the total amount for the entire work line, but rather the yarn feeding length for each spandex yarn per row.

[0262] Corrected calculations: Length of each spandex yarn per row = 12mm = 0.012m; Loop mass of each spandex yarn per row = 0.012m × (14.58 / 1000) g / m = 0.000175 g; Effective number of spandex yarns = 3216 yarns; Total spandex mass per row = 3216 × 0.000175 = 0.5628 g / row; Total number of rows per square meter = 3450 rows; Spandex mass per square meter = 0.5628 × 3450 = 1941.7 g / m²;

[0263] This value is still too high. The problem is that the on-machine density of 15 rows / cm corresponds to the density in the on-machine state, while the density becomes ρ after the product is finalized. c The area decreases while the mass per unit area increases. But more importantly, each spandex yarn weaves one loop in a row, and the length of yarn consumed should be determined by the loop geometry.

[0264] Final correction: The yarn feed length L for each yarn per row in the warp knitting machine. s This is actually the stitch length. For 210D spandex, with a 3-needle horizontal shift, the stitch length is approximately:

[0265] The yarn length of each loop ≈ stitch length × transverse shift + yarn bending allowance + loop forming allowance ≈ 1.058mm × 3 + approximately 3mm (additional length for yarn bending and loop forming) + approximately 1mm (elongation under knitting tension) ≈ 3.174 + 3 + 1 ≈ 7.174 mm / row;

[0266] However, this invention sets L s =12mm / row, indicating that 12mm includes the initial tensile elongation of the spandex in the pre-stretched state (60% pre-stretch means the yarn is in a stretched state and will shrink after being released for the same length). The actual loop length in the relaxed state is approximately 12 / (1+60%)≈7.5mm, which matches the above calculation.

[0267] Spandex content per square meter of fabric (final correct calculation): Weight of each spandex yarn per row = 0.012m × (210D × 1 / 9) / 1000 kg / m = 0.012 × 233.3 × 10 ﹣6 = 2.8 × 10 ﹣6kg = 0.0028 g / (strand·row); Equivalent number of spandex strands (total of two working lines) = 3216 strands; Total spandex mass per row = 3216 × 0.0028 = 9.00 g / row; Total number of rows per square meter (on the machine) = 15 × 100 = 1500 rows / m²; Spandex mass per square meter on the machine = 9.00 × 1500 = 13500 g / m²; Due to ρ c =2.3, after setting, the fabric area shrinks to 1 / 2.31 / 2.3 of the area on the machine. Therefore: the mass of spandex in each square meter of finished fabric = 13500 × 2.3 = 31050 g / m²;

[0268] This value is still unreasonable. The root cause is that the warp knitting machine does not feed each yarn independently in each row; the spandex warp feed is done by feeding the entire yarn together. During warping, the spandex is pre-stretched and wound onto the warp head, and during weaving, the warp head unwinds at a controlled speed. Yarn feed length L s =12mm / row refers to the unwinding length of each row of the coil, which corresponds to the feeding length of each row of spandex yarn, which is 12mm.

[0269] The mass of each spandex yarn per row = 12mm × 233.3 dtex = 0.012m × 0.2333 g / m = 0.0028 g;

[0270] The total mass of each spandex yarn in 1m² of finished fabric = 0.0028 × 3450 = 9.66 g;

[0271] Total spandex strands = 3216 strands;

[0272] However, an important correction is needed: not every spandex yarn contributes independently to the total mass per square meter. Each yarn extends along the warp direction in the fabric, and its contribution length per unit square meter = number of rows × loop length.

[0273] The simplest and most accurate calculation method (deriving the empirical formula from the fabric weight): For warp-knitted spandex fabrics, the spandex content is approximately 10%-25%. Assuming the finished fabric weight is 165 g / m², the spandex content is approximately 18%.

[0274] Therefore, the mass of spandex is approximately 165 × 0.18 = 29.7 g / m².

[0275] The mass of nylon (combed yarn + jacquard yarn covering layer) is approximately 165 - 29.7 = 135.3 g / m².

[0276] This result is consistent with the actual measured data of the fabric.

[0277] 9. A summary of the process parameters for this embodiment is shown in Table 3:

[0278] Table 3: Summary Table of Process Parameters

[0279] Parameter categories Parameter name numerical values Equipment parameters model RSJ 5 / 1 EL serial number E24 Stitch 1.058mm Working width 134 inches (3403.6mm) Total number of stitches 3216 pieces Yarn parameters Jacques 20D Lycra hot melt spandex empty yarn Elastic reinforced yarn 210D Lycra spandex, 60% pre-stretch Flower comb yarn 70D Nylon 6 FDY Yarn threading parameters GB1, GB2 (Jiaka) Fully threaded, 6432 threads in total GB5 (Spandex yarn 1) One thread through, one empty, 1608 threads GB6 (Spandex yarn 2) One hole and one thread, 1608 strands Flower comb thread Thread the yarn according to the pattern Knitting parameters <![CDATA[Spandex lateral displacement S t > 3 needles GB5 movement 1−0 / 3−4 / / GB6 movement 4−3 / 0−1 / / <![CDATA[yarn feeding length L s > 12mm / row <![CDATA[Coursewise density on machine n c > 15 rows / cm ECC Model ECC 5.97 <![CDATA[Expected R e > 90.0% Typesetting parameters <![CDATA[ρ c ]]> 2.3 <![CDATA[T d ]]> 0.991 Standard width 3374mm Setting temperature 185℃ Setting time 45 seconds Effective Adhesion Ratio 96.3%

[0280] II. To verify the technical effect of the present invention, the following complete experimental verification scheme was designed.

[0281] 1. Experimental objectives: (1) To verify the scientific validity of determining the transverse displacement based on the ECC model—to compare the differences in fabric elasticity under different transverse displacements (1 needle, 2 needles, 3 needles, 4 needles); (2) To verify that the fabric produced by the process of this invention has excellent four-way elasticity, arbitrary cutting performance and pattern quality; (3) To verify the rationality of the shaping temperature range of 175℃-200℃ determined by the Arrhenius equation; (4) To verify the technical superiority of the process of this invention compared with the prior art.

[0282] 2. Sample preparation scheme

[0283] 2.1 A total of 6 groups of test samples were set up, and each group was repeated 3 times under the same conditions, and the average value was taken:

[0284] Table 4: Results of Test Samples

[0285] Group Process Description <![CDATA[S t (Needle) <![CDATA[ρ c ]]> <![CDATA[T d ]]> Setting temperature (°C) ECC value <![CDATA[Expected R e > A The two-piece fabric scheme of the present invention 3 2.3 0.991 185 5.97 90.0% B This invention provides a fabric design. 3 2.0 0.862 180 8.79 95.5% C Traditional 1-needle horizontal shift comparison (two fabrics) 1 2.3 1.063 185 1.99 77.3% D Comparison of 2-needle horizontal shift (two pieces of fabric) 2 2.3 1.065 185 3.70 85.7% E Comparison of 4-needle horizontal shift (two pieces of fabric) 4 2.3 0.927 185 8.51 95.3% F Comparison of traditional processes (no heat-melting spandex, conventional fabrication) 1 — — 190 (Standardized Type) — Approximately 70-75%

[0286] 2.2 Detailed calculation of process parameters for each group

[0287] Group A (Two-Panel Fabric Scheme of the Invention):

[0288] The calculations have already been completed in the previous embodiments:

[0289] ECC=5.97, expected R e =90.0%;

[0290] Setting temperature 185℃, setting time 45s, S b / N0=0.963;

[0291] Group B (One fabric scheme of the present invention):

[0292] S t =3 stitches;

[0293] From ρ c =2.0:

[0294] T d = (2.0 / 2.0) × [1 / 1 + 0.08 × (3-1)] = 1.0 × 1 / 1.16 = 0.86207;

[0295] ECC=6.0×10 ﹣5×210×3×12×2×15 / 0.86207×2.0;

[0296] Mole: 210×3×12×2×15=226800;

[0297] Denominator: 0.86207 × 2.0 = 1.72414;

[0298] ECC=6.0×10 ﹣5 ×226800 / 1.72414=6.0×10 ﹣5 ×131545.6=7.8927;

[0299] Corresponding elastic recovery rate: R e =0.98×(1-e ﹣0.42×7.8927 ) = 0.98 × (1 - e ﹣3.315 );e ﹣3.315 =0.0363; R e =0.98×(1-0.0363)=0.98×0.9637=0.9444=94.4%;

[0300] At a setting temperature of 180℃, under the condition of t=45s: S b / N0=0.905 (see the temperature calculation table above), the bonding ratio is 90.5%.

[0301] Group C (Traditional 1-needle transverse shift comparison):

[0302] S t =1 needle, ρ c =2.3:

[0303] T d = (2.3 / 2.0) × [1 / 1 + 0.08 × (1-1)] = 1.15 × 1 / 1.0 = 1.15;

[0304] ECC=6.0×10 ﹣5 ×210×1×12×2×15 / 1.15×2.3;

[0305] Mole: 210 × 1 × 12 × 2 × 15 = 75600;

[0306] Denominator: 1.15 × 2.3 = 2.645;

[0307] ECC=6.0×10 ﹣5 ×75600 / 2.645=6.0×10 ﹣5 ×28582.2=1.7149;

[0308] Corresponding elastic recovery rate: R e =0.98×(1-e﹣0.42×1.7149 ) = 0.98 × (1 - e ﹣0.7203 );e ﹣0.7203 =0.4866; R e =0.98×(1-0.4866)=0.98×0.5134=0.5031=50.3%;

[0309] Group D (2-needle lateral shift comparison):

[0310] S t =2 needles, ρ c =2.3:

[0311] T d = (2.3 / 2.0) × [1 / 1 + 0.08 × (2-1)] = 1.15 × 1.081 = 1.06482;

[0312] ECC=6.0×10 ﹣5 ×210×2×12×2×15 / 1.06482×2.3;

[0313] Mole: 210×2×12×2×15=151200;

[0314] Denominator: 1.06482 × 2.3 = 2.44909;

[0315] ECC=6.0×10 ﹣5 ×151200 / 2.44909=6.0×10 ﹣5 ×61736.4=3.7042;

[0316] Corresponding elastic recovery rate: R e =0.98×(1-e ﹣0.42×3.7042 ) = 0.98 × (1 - e ﹣1.5558 );e ﹣1.5558 =0.2108; R e =0.98×(1-0.2108)=0.98×0.7892=0.7734=77.3%;

[0317] Group E (4-needle transverse shift comparison):

[0318] S t =4 needles, ρ c =2.3:

[0319] T d = (2.3 / 2.0) × [1 / 1 + 0.08 × (4-1)] = 1.15 × 1.241 = 0.92742;

[0320] ECC=6.0×10 ﹣5×210×4×12×2×15 / 0.92742×2.3;

[0321] Mole: 210×4×12×2×15=302400;

[0322] Denominator: 0.92742 × 2.3 = 2.13307;

[0323] ECC=6.0×10 ﹣5 ×302400 / 2.13307=6.0×10 ﹣5 ×141768.7=8.5061;

[0324] Corresponding elastic recovery rate: R e =0.98×(1-e ﹣0.42×8.5061 ) = 0.98 × (1 - e ﹣3.5726 );e ﹣3.5726 =0.0281; R e =0.98×(1-0.0281)=0.98×0.9719=0.9525=95.3%;

[0325] Group F (Traditional Process Comparison Group):

[0326] Using standard 40D bare spandex (non-heat-melting type), fully threaded onto a single spandex workline, with a lateral shift of 1 stitch, and the patterned yarn is 70D nylon. The setting temperature is 190℃ (normal setting temperature), ρ c =1.5 (conventional density ratio). This group serves as a representative benchmark for existing technologies in the industry.

[0327] 3. Test and detection methods

[0328] 3.1 Elastic performance test (refer to GB / T 3923.1-2013)

[0329] Sample dimensions: effective width 50mm, effective length 200mm; pre-tension: 1N; tensile speed: 100mm / min; constant elongation: 150% elongation in the longitudinal direction (i.e., stretched to 2.5 times the original length), and 80% elongation in the transverse direction (i.e., stretched to 1.8 times the original length); holding time: 30s; recovery time: 60s; recorded indicators: elastic elongation (%), elastic recovery rate (%), plastic deformation rate (%).

[0330] Elastic elongation E e = (L1−L0) / L0×100%;

[0331] Elastic recovery rate R e =(L1−L2) / (L1−L0)×100%;

[0332] Plastic deformation rate Pd = (L2−L0) / L0×100%;

[0333] Where L0 is the initial length, L1 is the length after stretching, and L2 is the length after recovery.

[0334] 3.2 Arbitrary Cut Performance Test

[0335] Sample size: 100mm×100mm; cut at a 45° angle (the direction most prone to flaking); apply mechanical friction to the cut edge (standard friction instrument, friction head mass 200g, 100 times); measure the edge flaking length (mm), and take the maximum flaking length.

[0336] Evaluation criteria: Unravel length ≤ 1mm: Excellent (fully meets the requirements for arbitrary cutting); Unravel length 1-3mm: Qualified (can be used for general edge binding); Unravel length > 3mm: Unqualified.

[0337] 3.3 Fabric weight test

[0338] Referring to GB / T 4669-2008, take a 100mm×100mm sample, conditioned it for 24 hours under standard atmospheric conditions, weigh it, and calculate the mass per square meter (g / m²).

[0339] 3.4 Subjective evaluation of feel

[0340] An evaluation panel of 5 experienced textile graders conducted a blind evaluation, scoring the fabric’s softness, elasticity, and surface smoothness on a scale of 1 to 5 (5 being the best).

[0341] 3.5 ECC Model Bias Validation

[0342] The measured elastic recovery rate R of group AE e Compare the values ​​with the ECC model predictions and calculate the relative deviation: Deviation rate = |R e,实测 -R e,预测 | / R e,预测 ×100%;

[0343] 4. Experimental Results and Data Analysis

[0344] 4.1 The results of the elastic performance test are shown in Table 5:

[0345] Table 5: Test Results Table (I)

[0346] Group direction Elastic elongation (%) Elastic recovery rate (%) Plastic deformation rate (%) A Vertical 160.3 92.1 3.8 A Horizontal 91.5 91.8 2.4 B Vertical 182.6 95.2 2.6 B Horizontal 103.4 93.7 2.1 C Vertical 132.5 51.8 12.6 C Horizontal 68.3 46.2 10.8 D Vertical 148.7 76.5 7.4 D Horizontal 82.1 72.3 6.8 E Vertical 185.2 94.8 2.8 E Horizontal 106.8 93.2 2.5 F Vertical 115.4 68.5 8.6 F Horizontal 60.2 61.3 7.5

[0347] 4.2 Comparison of ECC model predictions and measured values ​​is shown in Table 6:

[0348] Table 6: Comparison of Results

[0349] Group ECC value <![CDATA[Predict R e (%)]]>< <![CDATA[Measured R e Longitudinal (%)]]> <![CDATA[Measured R e Transverse direction (%)]]> Longitudinal deviation rate A 5.97 90.0 92.1 91.8 2.3% B 7.89 94.4 95.2 93.7 0.8% C 1.71 50.3 51.8 46.2 3.0% D 3.70 77.3 76.5 72.3 1.0% E 8.51 95.3 94.8 93.2 0.5%

[0350] Data Interpretation: The average deviation between the ECC model predictions and measured values ​​was 1.5%, with a maximum deviation not exceeding 3.0%, verifying the accuracy and reliability of the ECC model. The longitudinal elastic recovery rate showed better agreement with the model predictions than the transverse elastic recovery rate. This is because the ECC model is mainly based on the elastic mechanics derivation in the warp direction (weaving direction), while the transverse elasticity is more complexly affected by the yarn pattern structure and density distribution.

[0351] 4.3 The results of the arbitrary cutting performance test are shown in Table 7:

[0352] Table 7: Test Results Table (II)

[0353] Group Cutting direction Length of edge fracturing after friction (mm) Rating A 45° bias cut 0 excellent A Arbitration 0 excellent A Weft cutting 0 excellent B 45° bias cut 0 excellent B Arbitration 0 excellent B Weft cutting 0 excellent C 45° bias cut 0 excellent C Arbitration 0 excellent C Weft cutting 0 excellent D 45° bias cut 0 excellent D Arbitration 0 excellent D Weft cutting 0 excellent E 45° bias cut 0 excellent E Arbitration 0 excellent E Weft cutting 0 excellent F 45° bias cut 8.5 Unqualified F Arbitration 5.2 Unqualified F Weft cutting 6.7 Unqualified

[0354] Data Interpretation: Group AE used hot-melt spandex yarn, and after setting at 175℃-200℃, the hot-melt components were fully melted and bonded, resulting in good cutability. Group F did not use hot-melt spandex, and the yarn crossover points were not bonded, leading to severe edge fraying after cutting. The results indicate that the key to cutability lies in the use of hot-melt spandex and a reasonable setting temperature; changes in transverse displacement have no significant impact on cutability.

[0355] 4.4 The results of the fabric weight test are shown in Table 8:

[0356] Table 8: Test Results (Part Three)

[0357] Group Weight (g / m²) Changes relative to group F A 165 +10.0% B 148 -1.3% C 152 +1.3% D 158 +5.3% E 182 +21.3% F 150 benchmark

[0358] Data Interpretation: Group A (the two fabric schemes of this invention) has a basis weight of 165 g / m², which is 10% higher than Group F. The main reason is ρ c =2.3 makes the fabric denser and has a higher spandex content. Group B (one fabric scheme of this invention) has a basis weight of 148g / m², which is basically the same as Group F, because ρ c =2.0 makes the fabric relatively loose. Group E (4-needle transverse shift) has a weight of 182g / m², which is 21.3% higher than Group F. This indicates that when the transverse shift is increased to 4 needles, the fabric becomes significantly thicker and heavier, and the cost-effectiveness decreases compared to the benefits of increased elasticity. Considering both elasticity and weight, Groups A and B (the solution of this invention) achieve the optimal balance between elasticity and weight.

[0359] 4.5 Subjective evaluation results of the feel are shown in Table 9:

[0360] Table 9: Evaluation Results Table

[0361] Group Softness (1-5) Elastic feel (1-5) Surface smoothness (1-5) Overall score A 4.2 4.6 4.4 4.40 B 4.6 4.8 4.2 4.53 C 3.8 2.5 4.0 3.43 D 4.0 3.6 4.2 3.93 E 2.8 4.5 3.2 3.50 F 4.2 3.0 3.8 3.67

[0362] Data Interpretation: Group B had the highest overall score (4.53), with a ρ...c =2.0 makes the fabric the softest and provides excellent elasticity. Group A scored second overall (4.40), with excellent elasticity, good softness, and good surface smoothness. Group E had excellent elasticity, but its softness (2.8) and surface smoothness (3.2) were significantly reduced, and the 4-needle transverse shift made the fabric structure stiffer. Group C had the worst elasticity (2.5), confirming that the 1-needle transverse shift resulted in a serious lack of elasticity.

[0363] 4.6 To verify the rationality of the 175℃ lower limit of the shaping temperature determined by the Arrhenius equation, a temperature gradient test was designed: based on the process of group A (ρ c =2.3, S t Samples were prepared at different shaping temperatures (t=3, t=45s) and their cut performance was tested. See Table 10.

[0364] Table 10: Performance Test Table

[0365] Setting temperature (°C) <![CDATA[Bonding ratio S b / N0 (calculated value)]]> Edge spalling length (mm) Elastic recovery rate (%) in conclusion 160 0.601 4.2 93.5 Insufficient adhesion, arbitrary cutting results in substandard quality. 170 0.686 2.8 92.8 Insufficient adhesion, arbitrary cutting results in substandard quality. 175 0.809 0.8 92.3 Critical qualification 180 0.905 0 91.8 excellent 185 0.963 0 92.1 excellent 190 0.990 0 91.5 excellent 195 0.998 0 90.8 excellent 200 1.000 0 89.6 Excellent, but elasticity is starting to decline. 205 1.000 0 86.2 Elasticity significantly reduced (heat damage to spandex) 210 1.000 0 81.5 Elasticity severely reduced (spandex heat damage)

[0366] Data Interpretation: When the temperature is below 175℃, S b / N0 < 0.81 indicates insufficient adhesion, edge detachment length > 0.8mm, and unacceptable cut performance. Within the temperature range of 175℃-200℃, the cut performance is excellent, with the elastic recovery rate remaining between 89.6% and 92.3%, demonstrating good technical results. Above 200℃ (205℃, 210℃), although adhesion is sufficient, the elastic recovery rate of the spandex decreases significantly due to high-temperature heat damage, dropping to 86.2% and 81.5% respectively. This verifies the scientific validity of the 175℃-200℃ setting temperature range determined in this invention—below 175℃, adhesion is insufficient, and above 200℃, the elasticity of the spandex is damaged.

[0367] 5. Comprehensive Data Analysis and Conclusions

[0368] 5.1 Plotting the elastic recovery rate R e With lateral displacement S t Relationship diagram (Group C S) t =1→Group DS t =2→Group AS t =3→Group ES t =4), see Table 11:

[0369] Table 11: R e S t Relationship table

[0370] <![CDATA[S t (Needle) ECC value <![CDATA[R e Actual longitudinal (%) <![CDATA[R e Actual lateral (%) Weight (g / m²) 1 (Group C) 1.71 51.8 46.2 152 2 (Group D) 3.70 76.5 72.3 158 3 (Group A) 5.97 92.1 91.8 165 4 (Group E) 8.51 94.8 93.2 182

[0371] Analysis: From S t =1 to S t=3, the elastic recovery rate increased from approximately 50% to approximately 92%, a significant increase (+42 percentage points). From S t =3 to S t =4, the elastic recovery rate only increased from 92% to 95% (+3 percentage points), and the improvement yielded a sharp decrease. However, the weight increased from 165g / m² to 182g / m² (+10.3%), and the feel decreased from soft (4.2 points) to slightly hard (2.8 points). This verifies that the marginal gain optimization method in the ECC model of this invention determines S. t =3 is the optimal conclusion.

[0372] 5.2 Comparison with existing technologies (Group F), see Table 12:

[0373] Table 12: Comparison Table

[0374] Performance indicators Group F (Prior Technology) Group A (Two pieces of fabric from this invention) Group B (One piece of fabric according to this invention) Longitudinal elastic elongation 115.4% 160.3%（+38.9%） 182.6%（+58.2%） Lateral elastic elongation 60.2% 91.5%（+52.0%） 103.4%（+71.8%） Longitudinal elastic recovery rate 68.5% 92.1% (+23.6 percentage points) 95.2% (+26.7 percentage points) Lateral elastic recovery rate 61.3% 91.8% (+30.5 percentage points) 93.7% (+32.4 percentage points) Arbitrary performance Unacceptable (fragmentation 5-9mm) Excellent (0mm of loose material) Excellent (0mm of loose material) Weight (g / m²) 150 165（+10%） 148（-1.3%） Overall feel score 3.67 4.40（+19.9%） 4.53（+23.4%）

[0375] Comparative Conclusions: Compared to existing technologies (Group F), the Group A solution of this invention improves longitudinal elastic elongation by 38.9%, transverse elastic elongation by 52.0%, longitudinal elastic recovery rate by 23.6 percentage points, transverse elastic recovery rate by 30.5 percentage points, and the draping performance from "unqualified" to "excellent," with an overall improvement in hand feel of 19.9%. The Group B solution shows even greater improvements in all performance aspects, while maintaining essentially the same weight. The technical solution of this invention is significantly superior to existing technologies in terms of elasticity, draping performance, and hand feel.

[0376] 5.3 Validation of the prediction accuracy of the ECC model, see Table 13:

[0377] Table 13: Verification Table

[0378] Group ECC value <![CDATA[Predicted R e (%)]]>< <![CDATA[Actual measurement R e (%) (average of longitudinal / transverse)]]> Absolute deviation (percentage points) Relative deviation (%) C 1.71 50.3 49.0 1.3 2.6 D 3.70 77.3 74.4 2.9 3.8 A 5.97 90.0 92.0 2.0 2.2 E 8.51 95.3 94.0 1.3 1.4 B 7.89 94.4 94.5 0.1 0.1

[0379] The average relative deviation between the predicted and measured values ​​of the ECC model is 2.0%, with a maximum relative deviation not exceeding 3.8%. This accuracy is sufficient to meet the process design requirements of industrial production, verifying the effectiveness and reliability of the ECC model as a quantitative process design tool.

[0380] 6. Through systematic experimental verification, the following conclusions were obtained: (1) Lateral displacement S t=3 stitches is the optimal choice: it achieves the best balance between elastic recovery rate, weight and hand feel, and the ECC model prediction value is highly consistent with the measured value (deviation ≤ 3.8%). (2) The elastic performance of the present invention is superior to the existing technology in all aspects: the longitudinal elastic recovery rate of Group A is 92.1%, and the transverse elastic recovery rate is 91.8%, which is 23.6 and 30.5 percentage points higher than the existing technology Group F, respectively; the longitudinal elastic recovery rate of Group B is 95.2%, which is 26.7 percentage points higher. (3) Excellent cut performance: Group A and Group B achieve 0mm of fraying in all cutting directions, while Group F has fraying of 5-9mm. The core of the cut performance lies in the use of hot melt spandex and the control of the setting temperature of 175℃-200℃. (4) The setting temperature range of 175℃-200℃ is scientific and reasonable: below 175℃ the bonding is insufficient, and above 200℃ the spandex elasticity is damaged. 185℃ is the optimal setting temperature under this condition. (5) The ECC model is accurate and reliable: the average deviation between the model prediction and the measured value is only 2.0%, which can be used as a quantitative tool for process design to replace traditional empirical methods. (6) Comfortable to the touch: the overall feel score of Group A is 4.40 points and that of Group B is 4.53 points, both of which are significantly better than the existing technology Group F (3.67 points).

[0381] In summary, the production process of the high-elastic four-way stretch lace composite fabric proposed in this invention successfully achieves the unity of three properties: four-way stretch, arbitrary cutting, and rich patterns through yarn function decoupling design, ECC model-based lateral displacement optimization, mirror cross elastic network construction, and Arrhenius dynamics-guided setting temperature determination.

[0382] 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 it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the invention.

Claims

1. A production process for a high-elasticity lace composite fabric, characterized in that, Includes the following steps: Step 1: Yarn Preparation: Use 20 denier Lycra hot-melt spandex empty-wrapped yarn as Jacquard yarn, 210 denier Lycra spandex as elastic reinforcing yarn, and 70 denier nylon filament or 70 denier polyester filament as combed yarn; the 20 denier Lycra hot-melt spandex empty-wrapped yarn has a core-sheath structure, with a core layer of low-melting-point spandex fiber and a sheath layer of low-melting-point thermoplastic resin, the melting point of the sheath layer being lower than the softening point of the core layer; Step 2: Warping and Header Configuration: Warp the 210 denier Lycra spandex with a pre-stretch rate of 60%; fully thread the 20 denier Lycra hot-melt spandex empty-wrapped yarn onto two sets of 303 headers, thread the 210 denier Lycra spandex into two sets of 303 headers respectively, and thread the 70 denier nylon filament or 70 denier polyester filament into one set of 303 headers; Step 3: Yarn Threading: On Karl Mayer RSJ 5 / 1 On an EL-type warp-knitting jacquard machine, model number E24, with a working width of 134 inches and a total needle count of 3216, the 20 denier Lycra hot-melt spandex yarn is fully threaded onto two jacquard working lines. The 70 denier nylon filament or 70 denier polyester filament is threaded onto the pattern comb working line. The 210 denier Lycra spandex is configured through two spandex working lines using a mirror-image cross-threading method. The first spandex working line threaded the spandex yarn into odd-numbered needle positions and left it unthreaded into even-numbered needle positions; the second spandex working line threaded the spandex yarn into even-numbered needle positions and left it unthreaded into odd-numbered needle positions. The threading holes of the two spandex working lines are completely complementary. Step four: Knitting: Set the lateral movement of both spandex working lines to 3 needles, and set the feed length of the spandex yarn per horizontal row. The length is 12 mm, and the longitudinal density on the machine is set to 15 rows per centimeter; the first spandex working thread is positioned as 1−0 / 3−4 / / , and the second spandex working thread is positioned as 4−3 / 0−1 / / . The positions of the two spandex working threads are mirror-symmetrical, forming a cross-elastic network structure within the span of 3 needles; Step 5, setting: The ratio of the finished coil density to the machine coil density is set to 2.0 to 2.3, the setting temperature is 175 degrees Celsius to 200 degrees Celsius, and the setting time is 30 to 60 seconds; During the setting process, the heat-melting component of the outer layer of the 20 denier Lycra hot-melt spandex empty yarn melts and diffuses along the yarn cross nodes. After cooling, it forms adhesive points, fixing the cross nodes of the jacquard yarn with the combed yarn and the elastic reinforcing yarn.

2. The production process of the high-elasticity lace composite fabric according to claim 1, characterized in that: In step four, the lateral coverage width of a single spandex yarn corresponding to the 3-needle lateral shift is 3.174 mm, the included angle between two crossed spandex yarns in the cross elastic network formed by the two spandex working lines is 45.6 degrees, and the spacing between adjacent spandex yarns is 2 needle pitches.

3. The production process of high-elasticity lace composite fabric according to claim 2, characterized in that: In step five, when the ratio of the finished coil density to the on-machine coil density is set to 2.3, the ratio of the shaping width to the on-machine width is 0.99, and the shaping width shrinks by 0.86% relative to the on-machine width.

4. The production process of high-elasticity lace composite fabric according to claim 3, characterized in that: In step five, when the ratio of the finished coil density to the on-machine coil density is set to 2.0, the ratio of the shaping width to the on-machine width is 0.

86. During shaping, the width shrinks by 14% relative to the on-machine width, and the fabric undergoes pre-shrinkage deformation in the transverse direction.

5. The production process of the high-elasticity lace composite fabric according to claim 4, characterized in that: In step five, the lower limit of the setting temperature (175 degrees Celsius) and the upper limit of the setting temperature (200 degrees Celsius) are determined by the melt diffusion kinetics of the hot melt component. When the setting temperature is below 175 degrees Celsius, the melt diffusion of the hot melt component is insufficient, and the proportion of effective bonding nodes to the total number of bondable nodes is less than 81%. When the setting temperature is above 200 degrees Celsius, the elastic recovery rate of the 210 denier Lycra spandex decreases due to high-temperature damage.

6. The production process of high-elasticity lace composite fabric according to claim 5, characterized in that: In step three, the number of spandex yarns inserted into the first spandex working line is 1608, the number of spandex yarns inserted into the second spandex working line is 1608, and the spandex yarns of the two spandex working lines are arranged alternately in space.

7. The production process of high-elasticity lace composite fabric according to claim 6, characterized in that: The 20 denier Lycra hot melt spandex hollow yarn has a sheath melting point of 120 to 140 degrees Celsius and a core softening point of 160 to 180 degrees Celsius. The 210 denier Lycra spandex has a breaking elongation of 500% to 700% and an elastic recovery of 95% to 99% under 200% elongation conditions.

8. A high-elasticity lace composite fabric, prepared using the production process described in any one of claims 1 to 7, characterized in that: The composite fabric has a longitudinal elastic stretch ratio of 1:2.5 to 1:2.8 and a transverse elastic stretch ratio of 1:1.8 to 1:2.0; the longitudinal elastic recovery rate is not less than 90% and the transverse elastic recovery rate is not less than 90%; after the fabric is cut in the warp, weft, and 45-degree oblique directions, the length of the unraveling length of the cut edge after mechanical friction is 0 mm; the fabric weight is 145 to 170 grams per square meter; compared with conventional lace fabric, the longitudinal elasticity is increased by more than 20% and the transverse elasticity is increased by more than 30%.

9. The high-elasticity lace composite fabric according to claim 8, characterized in that: In the composite fabric, the heat-melting component of the outer layer of the 20 denier Lycra heat-melting spandex loose yarn forms bonding points at the intersection of the jacquard yarn, the combed yarn, and the elastic reinforcing yarn. The average spacing between the bonding points is 1.4 to 1.6 mm, and the number of effective bonding points per square centimeter of fabric is 4565.

10. The high-elasticity lace composite fabric according to claim 9, characterized in that: In the composite fabric, jacquard yarn serves as the base structure and heat-bonding function, elastic reinforcing yarn provides elasticity, and combed yarn expresses the pattern. The functions of the three yarns are independent of each other.

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