Knitted fabric

Abstract

Disclosed is a knitted fabric. The knitted fabric comprises a bottom structure. At least one side of the knitted fabric has pile loops or cut loops; polyamide composite crinkled fibers account for 50 wt% or more of the fibers of the formed pile loops and cut loops; the polyamide composite crinkled fibers contain 5-50 wt% of a polyether structural unit; and in a dry state, the ratio of the height H1 of the pile loops and cut loops formed by the polyamide composite crinkled fibers to the diameter D of the polyamide composite crinkled fibers is 1.0-15.0. The knitted fabric of the present invention not only has good water absorption and retention properties, but also has a good anti-reverse osmosis effect, and can be widely used in fields where water absorption, water retention, diffusion, etc., of fabrics, are required, such as clothing, hygienic products and cleaning articles.

Description

A knitted fabric Technical Field

[0001] The invention relates to a knitted fabric. Background Art

[0002] With the improvement of living standards, people have more and more requirements for clothing fabrics, and products with high water absorption and comfort are very popular. For this reason, people have conducted a lot of research.

[0003] For example, patent document CN214983853U discloses a functional fabric for preventing leakage during menstruation. The fabric comprises a first functional fabric, a second functional fabric, and a third anti-leakage functional fabric. The second functional fabric is a polyester single-sided hydrophilic terry cloth with a maximum wetting radius of greater than 17 mm on the wetted surface. Although the second functional fabric has a large diffusion area, it can cause reverse osmosis when squeezed, which can easily cause discomfort.

[0004] For example, patent document CN1756864A discloses a woven fabric containing two different types of yarns and clothing containing the same. Specifically, it discloses a fleece fabric with a ground weave and looped fleece extending from at least one surface of the ground weave. The loop structure is composed of yarns with both high and low self-elongation upon water absorption. After absorbing water, the yarns with high self-elongation stretch, increasing the gaps between the loops. While this fabric has good water absorption, diffusion, and breathability, it still suffers from reverse osmosis caused by squeezing.

[0005] For example, patent document JP2006207052A discloses a pile fabric and its fiber products, specifically a pile fabric containing curled fibers in the pile portion. When wet, the curling rate of the curled fibers is reversibly reduced, the pile height becomes larger, and the stickiness and wetness can be reduced, but the problem of high reverse osmosis is also not solved. Summary of the Invention

[0006] The object of the present invention is to provide a knitted fabric with excellent water absorption and water retention and anti-reverse osmosis properties.

[0007] The technical solutions of the present invention are as follows:

[0008] A knitted fabric comprises a base structure, wherein at least one side of the knitted fabric is formed of terry loops or cut loops, wherein the fibers forming the terry loops and cut loops contain polyamide composite crimped fibers accounting for more than 50 wt%; the polyamide composite crimped fibers contain 5 to 50 wt% of polyether structural units; and in a dry state, the ratio of the height H1 of the terry loops and cut loops formed by the polyamide composite crimped fibers to the diameter D of the polyamide composite crimped fibers is 1.0 to 15.0.

[0009] The height H1 and width L1 of the loops and cut loops formed by the polyamide composite crimped fiber in a dry state, and the height H2 and width L2 of the loops and cut loops formed by the polyamide composite crimped fiber in a wet state satisfy the following relationship: 0.10≤[(H2 / L2)-(H1 / L1)] / (H1 / L1)≤0.70 Formula 1.

[0010] The height H3 of the bottom structure in a dry state and the height H4 in a wet state preferably satisfy the following relationship: [(H4-H3) / H3]≤0.10 (Equation 2).

[0011] The ratio of the longitudinal density C to the transverse density W of the surface of the knitted fabric having loops or cut loops is preferably greater than 1.5.

[0012] Preferably, the loops or cut loops on at least one side of the knitted fabric are all formed by polyamide composite crimped fibers, and the volume V after water absorption of all the loops or cut loops on the loop or cut loop surface of the knitted fabric of 10 cm×10 cm formed by polyamide composite crimped fibers is 湿润 and the volume before water absorption V 干燥 Satisfies the following relationship, (V 湿润 -V 干燥 )≤5.0cm 3 Formula 3,

[0013] The single filament fineness of the fibers forming the loops and cut loops is preferably larger than the single filament fineness of the fibers forming the base weave.

[0014] The single-filament fineness of the fibers forming the base structure is preferably 1.0 dtex or less.

[0015] Preferably, the thickness of the knitted fabric is less than 4.0 mm, and the water absorption of the knitted fabric of 10 cm×10 cm is greater than 7.0 g / mm.

[0016] The present invention selects polyamide composite crimped fibers containing polyether structural units that can absorb water and elongate to form loops or cut loops, and adjusts the relationship between the height of the loops and cut loops and the fiber diameter so that the loops and cut loops are not easily crushed after absorbing water. The resulting fabric not only has excellent water absorption and water retention properties, but also has excellent anti-reverse osmosis effect. It can be widely used in fields that have requirements for fabric water absorption, diffusion and water retention, such as clothing, sanitary products, cleaning products, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic diagram of the intersection of the terry loops and the base fabric in the knitted fabric of the present invention, wherein H1 is the height of the terry loops when dry, L1 is the width of the terry loops when dry; H2 is the height of the terry loops when wet, and L2 is the width of the terry loops when wet.

[0018] FIG2 is a schematic diagram of a loop-cut knitted fabric according to the present invention. DETAILED DESCRIPTION

[0019] The knitted fabric of the present invention is a terry weave fabric, comprising a base weave, and having at least one side of the knitted fabric formed as a loop pile or cut pile, wherein the cut loops are formed by shearing the terry. Specifically, the knitted fabric may have one side with loops or cut loops, while the other side may be free of loops or cut loops. The knitted fabric may have one side with loops and the other with cut loops, or both sides may have loops or cut loops. Both loops and cut loops may also coexist on the same side of the fabric. Considering the knitted fabric's production process, water absorption, and reverse osmosis performance, it is preferred that both sides of the knitted fabric have loops.

[0020] The polyamide composite crimped fibers account for more than 50 wt% of the fibers forming the pile loops and the cut loops, and the polyamide composite crimped fibers contain polyether structural units accounting for 5-50 wt% of the polyamide composite crimped fibers.

[0021] The presence of polyether structural units gives the polyamide composite crimped fiber its natural crimping properties. It can stretch after absorbing water and return to its original crimped state after drying. After absorbing water, the loops or cut loops formed by the polyamide composite crimped fiber stretch along the plane where they lie, increasing the space they create and improving the knitted fabric's water absorption and retention.

[0022] The content of polyether structural units significantly influences the crimp morphology and water absorption and elongation of polyamide composite crimped fibers. When the content of polyether structural units is less than 5wt%, the fiber exhibits poor natural crimping properties and fails to elongate after absorbing water. The resulting loops and cut loops are unable to absorb and elongate, resulting in low water absorption and retention in knitted fabrics. When the content of polyether structural units exceeds 50wt%, the fiber exhibits poor spinnability. Taking into account both the spinnability of the polyamide composite crimped fibers and the water absorption and retention of the knitted fabrics, the present invention preferably employs a polyether structural unit content of 20-50wt% in the polyamide composite crimped fibers.

[0023] The polyether structural unit is not particularly limited and can be one or more of polyethylene glycol structural units, polypropylene glycol structural units, and polybutylene glycol structural units. Polyethylene glycol structural units are preferred. In this case, the polyamide composite crimped fiber has better water absorption and stretchability, and the knitted fabric made therefrom has better water absorption and water retention.

[0024] The polyamide composite crimped fiber can be a concentric core-sheath type, eccentric core-sheath type, or side-by-side type composite fiber formed by component 1 and component 2. The area ratio of component 1 to component 2 is preferably 20 / 80 to 80 / 20, more preferably 40 / 60 to 60 / 40. The present invention does not particularly limit the specific polymers of component 1 and component 2, and polyamide 4, polyamide 6, polyamide 66, etc. can be listed. The polyether structural unit can be distributed only in component 1 or component 2, or can be distributed in both component 1 and component 2. In order to enable the polyamide composite crimped fiber to obtain good crimping properties and water absorption and elongation, it is preferred that the polyether structural unit is distributed only in component 1 or component 2.

[0025] The polyamide composite crimped fiber can be a fully drawn yarn (FDY) or a false twisted yarn (DTY). In order to obtain better water absorption and water retention, the relatively fluffy false twisted yarn is preferred.

[0026] In addition to the loops or cut loops formed by the polyamide composite crimped fiber, the knitted fabric may also contain loops or cut loops formed by other fibers. These other fibers may be one or more of ordinary polyester (such as ordinary PET) fibers, modified polyester (such as cationic dyeable polyester) fibers, monocomponent polyamide fibers, polyurethane fibers, polyethylene fibers, polypropylene fibers, cotton fibers, viscose cellulose fibers, and the like. Furthermore, when the loops or cut loops are formed by other fibers, the loops or cut loops formed by the other fibers and the loops or cut loops formed by the polyamide composite crimped fiber may be located on the same side of the knitted fabric, or on different sides of the knitted fabric.

[0027] To ensure good water absorption and retention in knitted fabrics, the fibers forming the loops and cut loops must comprise at least 50% by weight of polyamide composite crimped fibers. The greater the proportion of polyamide composite crimped fibers, the greater the water absorption and retention space in the knitted fabric after water absorption, and the higher the water absorption and retention capacity. When the proportion of polyamide composite crimped fibers is less than 50%, the loops and cut loops formed by the other fibers, which make up a larger proportion, lack sufficient space for water absorption and retention after water absorption, resulting in lower water absorption and retention in the knitted fabric.

[0028] In the present invention, the ratio of the height H1 of the loops and cut loops formed by the polyamide composite crimped fiber in a dry state to the diameter D of the polyamide composite crimped fiber (H1 / D) is 1.0 to 15.0. The H1 refers to the distance between the highest point of the loops or cut loops and the horizontal plane of the upper surface of the base fabric when the knitted fabric is placed horizontally with the loops and cut loops to be tested facing upward; the D refers to the fiber bundle diameter of the polyamide composite crimped fiber. When H1 / D is within the range of 1.0 to 15.0, the loops and cut loops have a certain initial water absorption space, and the water absorption and water retention space rapidly increases after water absorption, which is conducive to rapid water absorption. If H1 / D is less than 1.0, the initial water absorption space of the loops and cut loops is small, and when the amount of liquid is large, it cannot be absorbed quickly, and side leakage is likely to occur. When H1 / D is greater than 15.0, the center of gravity of the pile and cut loops is too high, the fiber stiffness is insufficient, and the pile and cut loops are unstable. In particular, when squeezed by external force after absorbing water, the spaces formed by the pile and cut loops are compressed, and the absorbed water is easily squeezed out, causing reverse osmosis. The preferred H1 / D is 1.0-10.0.

[0029] The height H1 and width L1 of the loops and cut loops formed by the polyamide composite crimped fiber in a dry state, and the height H2 and width L2 of the loops and cut loops formed by the polyamide composite crimped fiber in a wet state satisfy the following relationship: 0.10≤[(H2 / L2)-(H1 / L1)] / (H1 / L1)≤0.70 Formula 1.

[0030] The width of the loop or cut loop refers to the distance between the two points where a single loop or cut loop intersects with the horizontal plane of the upper surface of the base fabric when the knitted fabric is placed horizontally with the loop or cut loop to be measured facing upward.

[0031] This is because if the height of the loops or cut loops formed by the polyamide composite crimped fibers increases little after absorbing water, or if the ratio of the increase in width of the loops or cut loops formed by the polyamide composite crimped fibers is greater than the ratio of the increase in height, that is, if the value of Formula 1 is small, the loops or cut loops formed by the polyamide composite crimped fibers will have less space to absorb water, resulting in a lower water absorption capacity and poor anti-reverse osmosis performance. If the height of the loops or cut loops formed by the polyamide composite crimped fibers increases too much after absorbing water, that is, if the value of Formula 1 is large, the loops or cut loops formed by the polyamide composite crimped fibers will be too high after absorbing water and may collapse, leading to a tendency for reduced water retention and anti-reverse osmosis performance. Preferably, the value of Formula 1 is 0.30 to 0.60.

[0032] The fibers forming the bottom tissue are not particularly limited, but are preferably yarns with low water absorption elongation or no elongation upon water absorption. Examples include one or more of ordinary polyester fibers (such as PET), modified polyester fibers (CDPET), single-component polyamide fibers (NY6 or NY66), polyethylene fibers, polypropylene fibers, cotton fibers, and viscose fibers.

[0033] Preferably, the height H3 of the bottom structure of the knitted fabric of the present invention in a dry state and the height H4 in a wet state satisfy the following relationship: [(H4-H3) / H3]≤0.10 (Equation 2).

[0034] This is because within the above range, the loops or cut loops formed by the polyamide composite crimped fiber exhibit good stability. After absorbing water, the loops or cut loops extend as much as possible, increasing the water absorption space, improving water absorption and retention, and simultaneously improving reverse osmosis resistance. However, as this rate of change increases, the stability of the loops or cut loops deteriorates. Although the loops or cut loops formed by the polyamide composite crimped fiber increase in height after absorbing water, the water absorption space is lost, preventing a proportional increase. This results in decreased water absorption and a tendency toward reduced reverse osmosis. Preferably, [(H4 - H3) / H3] is 0.05 or less.

[0035] Preferably, the ratio of the longitudinal density C to the transverse density W of the surface with terry or cut loops in the knitted fabric of the present invention is greater than 1.5, and more preferably less than 2.5. Within this range, the terry or cut loops are arranged closely in the longitudinal direction, allowing water to diffuse easily in the longitudinal direction after absorbing water, and preventing lateral leakage.

[0036] Due to the influence of water gravity, the volume of the loops or cut loops formed by other fibers may decrease after absorbing water. However, the loops or cut loops formed by the polyamide composite crimped fibers of the present invention increase in volume after absorbing water, and have a larger water absorption capacity.

[0037] Preferably, the loops or cut loops on at least one side of the knitted fabric are all formed by polyamide composite crimped fibers, and in a 10cm×10cm knitted fabric, the volume of the loops or cut loops on the loop surface or cut loop surface formed entirely by polyamide composite crimped fibers increases by 5cm after absorbing water compared to before absorbing water. 3 The following are three situations in which the "loops or cut loops on at least one side are entirely formed by polyamide composite crimped fibers": first, only one side of the knitted fabric is looped or cut, and the loops or cut loops are entirely formed by polyamide composite crimped fibers. The volume increase after water absorption is the result of testing this side; second, both sides of the knitted fabric are looped or cut, and the loops or cut loops are entirely formed by polyamide composite crimped fibers. The volume increase after water absorption can be tested on one side; third, both sides of the knitted fabric are looped or cut, the loops or cut loops on one side are entirely formed by polyamide composite crimped fibers, and the loops or cut loops on the other side are entirely formed by other fibers, or by other fibers and polyamide composite crimped fibers. In this case, the volume increase after water absorption is the result of testing the side where the loops or cut loops are entirely formed by polyamide composite crimped fibers.

[0038] The volume of the loop or cut loop before absorbing water (V干燥 ) and the volume after water absorption (V 湿润 ) can be calculated by the following formula: the volume of the loop or cut loop after absorbing water is increased by the value before absorbing water, which is V 湿润 -V 干燥 .

[0039] The units of C and W are "root / 2.54cm"; the units of L1, L2, H1, H2, and D are "cm", with an accuracy of 0.001.

[0040] By adjusting the relationship between the longitudinal density C, the transverse density W, the width and height of the loops or cut loops, and the fiber diameter, the volume of the loops or cut loops of the 10cm×10cm knitted fabric after absorbing water is preferably 5.0cm 3 The following can improve the reverse osmosis performance of knitted fabrics.

[0041] Preferably, the single-filament fineness of the fibers forming the terry and cut loops is greater than the single-filament fineness of the fibers forming the base fabric, thereby facilitating moisture transfer to the base fabric and improving the anti-reverse seepage performance of the knitted fabric. The fibers forming the terry and cut loops herein refer to all fibers that form terry and cut loops, not just the polyamide composite crimped fibers.

[0042] Preferably, the fibers forming the base fabric have a single-filament fineness of 1.0 dtex or less. This small single-filament fineness allows the moisture absorbed by the pile and cut loops to be quickly transferred to the base fabric, leaving the pile and cut loop surfaces relatively dry and providing improved anti-reverse osmosis performance. Furthermore, using fibers with a fine single-filament fineness for the base fabric enhances the fabric's feel.

[0043] Furthermore, the knitted fabric of the present invention has a thickness of less than 4.0 mm and a water absorption capacity of 7.0 g / mm or greater for a 10 cm x 10 cm knitted fabric. This is because the knitted fabric is initially relatively thin and light, making it comfortable for the human body when used in clothing products. After absorbing water, the loops and cut loops formed by the polyamide composite crimped fibers extend in their respective planes, increasing the thickness of the knitted fabric and improving its water absorption and retention capacity. After drying and dehumidification, the loops and cut loops return to their initial state, and the thickness of the knitted fabric decreases accordingly. This results in a knitted fabric that is thin and light when dry and has good water absorption and retention properties after absorbing water. Furthermore, the water absorption capacity of the 10 cm x 10 cm knitted fabric is more preferably between 7.0 and 20.0 g / mm. Within this range, the fabric exhibits good water absorption and retention properties and is resistant to reverse osmosis.

[0044] The knitted fabric of the present invention has excellent water absorption and water retention, anti-reverse osmosis properties, and is light, thin and comfortable. It can be widely used in fields that require fabric water absorption and water retention, longitudinal diffusion and anti-reverse osmosis properties, such as clothing, sanitary products, cleaning products, etc., and can effectively solve the problems of easy side leakage and reverse osmosis.

[0045] When only one side of the knitted fabric of the present invention has terry or cut loops, the other side without terry or cut loops can be coated or filmed. This fabric not only has high water absorption and retention properties but also has good waterproof properties, preventing liquid from penetrating and leaking to the other side after absorbing water. When filming is used, the film can be a polytetrafluoroethylene film, a polyurethane film, or the like. When coating is used, the fabric can be coated with polyurethane, semi-polyurethane, or polyvinyl chloride films.

[0046] The present invention will be further described below with reference to the following embodiments and comparative examples.

[0047] The test methods for the various parameters involved in the present invention are as follows:

[0048] 1. Confirmation of yarn type

[0049] Cut a 15×15 cm sample fabric along the warp direction and disassemble all the fibers in a complete structure from the loop or cut loop surface as the fibers to be tested.

[0050] According to "FZ / T 01057.8-2012 Test Methods for Identification of Textile Fibers Part 8: Infrared Spectroscopy", confirm whether the fiber to be tested is polyamide fiber.

[0051] Take 10 cm polyamide fiber, use paraffin embedding method to prepare slices and slices, observe under an optical microscope (select the magnification that can clearly image, such as 1000 times), and determine whether the cross-sectional structure of the polyamide fiber is core-sheath type, parallel type, or eccentric core-sheath type.

[0052] 2. Polyether structural unit content

[0053] 5 mg of the polyamide composite fiber determined by the test method (1) was placed in a test tube, and 5 ml of a solution prepared by 1,1,1,3,3,3-hexafluoro-2-propanol-d2 (CAS: 38701-74-5, Qiaoyi Biotechnology (Shanghai) Co., Ltd.) was added. Then, a nuclear magnetic resonance spectrometer (Bruker AVANCEⅢHD Asend500MHz) was used to test 1H-NMR. The characteristic peaks of the polyether structure (wavelengths 1297, 1250, 1112 cm) were calculated according to the test software provided by the equipment. -1 , -COC-, stretching vibration peak; wavelength 948,885cm -1, -COC-, bending vibration) area, and the content of polyether structural units in the polyamide composite fiber is obtained.

[0054] 3. Diameter D of polyamide composite fiber

[0055] Measured according to "GB / T 36422-2018 Chemical fibers - Determination of microstructure and diameter - Scanning electron microscopy method".

[0056] 4. Monofilament fineness

[0057] First, the linear density (T) of the yarn was measured according to ASTM D1907 / D1907M-12, Standard Test Method for Linear Density (Yarn Count) of Yarn - Hank Method. Paraffin-embedded sections were prepared and sliced, and then observed under an optical microscope (selecting a magnification that provides a clear image, such as 1000x). The number of single filaments (S) and the single filament fineness (T / S) were determined.

[0058] 5. Height and width of terry and cut loops, bottom weave height, and fabric thickness

[0059] Step a: Dry state

[0060] Under standard temperature and humidity conditions (20°C x 65%), cut a 1.0 x 0.5 cm fabric sample along the warp and weft directions and allow it to rest for 24 hours. Secure the sample, with the surface to be tested facing upward, to the side of a six-sided, flat cubic sample stand, with the warp direction perpendicular to the horizontal plane. Observe the sample using a KEYENCE VHX-2000C microscope at a magnification of 20 x 20, and use the microscope's depth synthesis function to display the sample cross-section in 3D. Select any loop or cut loop and mark the two points where the loop or cut loop intersects the horizontal plane of the base fabric. The straight-line distance between these two points is the loop or cut loop width, L1.

[0061] Randomly select a loop or cut loop and mark the point where the loop or cut loop is farthest from the horizontal plane of the base fabric's upper surface. Using the microscope's built-in "point to line distance" function, measure the distance between this farthest point and the horizontal plane of the base fabric's upper surface. Record this as the loop or cut loop's height H1. Using the microscope's built-in "distance between two lines" function, measure the distance between the horizontal plane of the base fabric's upper surface and the horizontal plane of its lower surface. Record this as the base fabric's height H3. Using the microscope's built-in "distance between two lines" function, measure the distance between the topmost plane of the sample and the horizontal plane of the sample stage. Record this as the fabric thickness d.

[0062] The above L1, H1, H3, and d are the average values ​​after testing 10 points.

[0063] Step b: When wet

[0064] Under standard temperature and humidity conditions (20°C x 65%), place the sample stand from step a with the fabric facing up. Use a dropper to measure 1 ml of grade tertiary water and drip it directly onto the fabric. Let it sit for 30 seconds. Using the same method as step a, measure the loop or cut loop width L2, loop or cut loop height H2, and bottom fabric height H4.

[0065] The above L2, H2, and H4 are the average values ​​after testing 10 points.

[0066] Cut two more pieces of fabric samples using the same method, repeat steps a and b above to measure them, and take the average of the results of the three pieces of fabric samples as the final result.

[0067] 6. Transverse density W and longitudinal density C

[0068] Cut three 10cm x 10cm pieces of fabric to be tested. Select the surface with the loops or cut loops as the test surface. Using a fabric density microscope (Changzhou Depu brand Y511B fabric density microscope), align a warp-direction row of loops or cut loops with the transverse starting scale line within the test range (2.54 x 2.54 cm). Count the number of warp-direction rows within the 2.54cm frame from the transverse starting scale line as the transverse density. Then, count the number of longitudinal loops or cut loops within the 2.54cm frame for the warp-direction row as the longitudinal density. Measure and calculate the remaining two fabric samples using the same method. Take the average of the data from the three samples as the fabric's transverse density (W) and longitudinal density (C).

[0069] 7. Water absorption

[0070] Under standard temperature and humidity conditions (20°C x 65%), take a 10cm x 10cm sample of fabric to be tested and let it rest for 24 hours. Then weigh and record its original weight (m1) (in g, rounded to three decimal places). Place the sample in a container filled with grade tertiary water. Allow the sample to absorb water and sink naturally. If it does not sink naturally, press it into the water and then lift it up, repeating this process 2-3 times. After completely soaking the sample in water for 10 minutes, remove it and hang it vertically, flat and flat (clamp it horizontally and let it droop vertically). Any water that has not been retained in the sample will drip out naturally. When the interval between dripping drops exceeds 30 seconds, the sample is considered to be no longer dripping. Immediately remove the sample with tweezers and weigh it (in g, rounded to three decimal places). The amount of water absorbed is (m2 - m1) / d, where d is the fabric thickness obtained in Test Method 5.

[0071] A precision balance (Shanghai Sunny Hengping Scientific Instrument Co., Ltd., AE523) was used to weigh the fabric.

[0072] Test two more pieces of fabric using the same method and take the average of the three tests as the final result.

[0073] 8. Reverse osmosis rate

[0074] Under standard temperature and humidity conditions (20°C x 65%), take three pieces of fabric to be tested with a size of 10 cm x 10 cm (warp x weft) and let them stand for 24 hours.

[0075] Weigh 10 sheets of 10cm x 10cm filter paper and record this as G1 (in g, rounded to three decimal places). Add 1.0ml of grade 3 water 1cm above the center of the fabric to be tested. After 1 minute, lay the 10 completely overlapping filter papers flat on top of the test sample, completely covering the fabric. Place a 2mm thick, 10cm x 10cm acrylic sheet on top of the filter paper. Add a 3kg load to the acrylic sheet. After 1 minute, remove the load, acrylic sheet, and filter paper. Weigh the filter paper and record this as G2 (in g, rounded to three decimal places).

[0076] Reverse osmosis rate (%) = [(G2-G1) / 2.5] x 100%.

[0077] The filter paper was weighed using a precision balance (Shanghai Sunny Hengping Scientific Instrument Co., Ltd., AE523).

[0078] The reverse seepage rates of the remaining two pieces of cloth were measured in the same way, and the average value was taken as the final result.

[0079] Example 1

[0080] On a 14G double-sided terry knitting machine, a 3.0mm high nose was used. The terry structure was made of a polyamide composite crimped fiber (167T-72f, core-sheath cross-section, DTY) containing 26% polyether structural units, with a yarn length of 100 cm / 100 loops. The base weave was a cationic dyeable polyester fiber (abbreviated as CDPET, 83T-72f, DTY), with a yarn length of 40 cm / 100 loops. This knitted double-sided terry knitted fabric was obtained.

[0081] The fabric was then shaped (190°C for 90 seconds), scouring (scouring agent 1 g / L, 90°C for 20 minutes), dyeing (acid dye ash, cationic dye ash, one-bath one-step process, 110°C for 30 minutes), resin-treated (one dip and one pad, water absorbent DR-906 from Nantong Dongrou Industry and Trade Co., Ltd., at a dosage of 15 g / L, 130°C for 180 seconds), and finishing (170°C for 90 seconds) to obtain the knitted fabric of the present invention. Specific parameters are shown in Table 1.

[0082] Example 2

[0083] The upper loop structure is made of a polyamide composite crimped fiber (167T-72f, core-sheath cross-section, DTY) with a polyether structural unit content of 26 wt%. The lower loop structure is made of a polyamide composite crimped fiber (referred to as crimped NY, 167T-72f, core-sheath cross-section, DTY) with a polyether structural unit content of 26 wt% and a polyester fiber (referred to as PET, 167T-72f, DTY) in a 1:1 ratio, to produce the knitted fabric of the present invention. Specific parameters are shown in Table 1.

[0084] Example 3

[0085] The upper loop structure was made of a polyamide composite crimped fiber (167T-72f, core-sheath cross-section, DTY) containing 26 wt% polyether structural units, and the lower loop structure was made of a polyester fiber (abbreviated as PET, 167T-72f, DTY). The remaining steps were the same as in Example 1 to obtain the knitted fabric of the present invention. Specific parameters are shown in Table 1.

[0086] Examples 4-5

[0087] The knitted fabric of the present invention was obtained by varying the content of the polyether structural unit in the polyamide composite crimped fiber and remaining the same as in Example 1. Specific parameters are shown in Table 1.

[0088] Examples 6 to 8

[0089] Polyamide composite crimped fibers of different deniers were selected, and the height of the pile loops H1 was varied by changing the height of the nose, with the rest being the same as in Example 1, to obtain the knitted fabric of the present invention. Specific parameters are shown in Table 1.

[0090] Example 9

[0091] The base fabric was made of benzaldehyde-modified nylon fiber (abbreviated as modified NY, 83T-72f, DTY), and the rest of the process was the same as in Example 1 to obtain the knitted fabric of the present invention. Specific parameters are shown in Table 2.

[0092] Example 10

[0093] The base fabric was made of nylon fiber (abbreviated as NY, 83T-72f, DTY), and the rest of the process was the same as in Example 1 to obtain the knitted fabric of the present invention. Specific parameters are shown in Table 2.

[0094] Examples 11-12

[0095] By adjusting the fiber length, the ratio of the longitudinal density C and the transverse density W of the loop surface is changed, and the rest is the same as in Example 1 to obtain the knitted fabric of the present invention. Specific parameters are shown in Table 2.

[0096] Examples 13 to 15

[0097] The knitted fabric of the present invention was obtained by varying the monofilament fineness of the polyamide composite crimped fiber and / or the base fabric fiber, with the remaining steps being the same as in Example 1. Specific parameters are shown in Table 2.

[0098] Example 16

[0099] A 14G single-sided terry knitting machine was used. The terry structure was made of a polyamide composite crimped fiber (167T-72f, core-sheath cross-section, DTY) with a polyether structural unit content of 26 wt%. The base weave fiber was a cationic dyeable polyester fiber (abbreviated as CDPET, 83T-72f, DTY). Single-sided terry fabric was knitted using the same procedures as in Example 1 to obtain the knitted fabric of the present invention. Specific parameters are shown in Table 2.

[0100] Example 17

[0101] The knitted fabric of Example 16 was laminated to a 13 μm polyurethane (PU) film (top adhesive viscosity 3-4 Pa·s, base adhesive viscosity 4-5 Pa·s, laminating pressure 45 N, drying at 95°C, film forming speed 10-15 m / min, laminating speed 20-25 m / min, curing temperature 65°C, and curing time 48 h). The remaining parameters were the same as in Example 16 to obtain the knitted fabric of the present invention. Specific parameters are shown in Table 3.

[0102] Example 18

[0103] A knitted fabric of the present invention was obtained on a 14G cut-loop terry knitting machine, using a 3.0 mm high nose and a polyamide composite crimped fiber (167T-72f, core-sheath cross-section, DTY) with a polyether structural unit content of 26 wt%. All other parameters were the same as in Example 1. Specific parameters are shown in Table 3.

[0104] Comparative Examples 1-2

[0105] The knitted fabric of the present invention was obtained by varying the content of the polyether structural unit in the polyamide composite crimped fiber and remaining the same as in Example 1. Specific parameters are shown in Table 3.

[0106] It can be seen from the data in the table that when the content of polyether structural units in the polyamide composite crimped fiber is less than 5wt%, the terry loops cannot stretch after absorbing water, the water absorption capacity of the fabric is small, and the anti-reverse osmosis effect is poor; when the content of polyether structural units in the polyamide composite crimped fiber is greater than 55wt%, although the terry loops stretch after absorbing water, the anti-reverse osmosis effect of the fabric is poor due to the large water absorption space.

[0107] Comparative Example 3

[0108] The terry structure uses a polyamide composite crimped fiber with a specification of 333T-144f, and the rest is the same as in Example 1 to obtain a knitted fabric. Specific parameters are shown in Table 3.

[0109] Since the fiber diameter is too large, the H1 / D value is less than 1.0, and the initial water absorption space of the terry is small, which not only has a poor anti-reverse osmosis effect, but also is prone to side leakage.

[0110] Comparative Example 4

[0111] The terry structure uses a polyamide composite crimped fiber with a specification of 83T-36f, and the height of the terry is changed by adjusting the height of the nose. The rest is the same as in Example 1 to obtain a knitted fabric. Specific parameters are shown in Table 3.

[0112] Due to the small fiber diameter and large loop height, the H1 / D value is greater than 15.0, the center of gravity of the loop is too high, the structure is unstable, and the anti-reverse osmosis effect is poor.

[0113] Comparative Example 5

[0114] The loop structure is made of polyester fiber (abbreviated as PET, 167T-72f, DTY), and the rest is the same as in Example 1 to obtain a knitted fabric. Specific parameters are shown in Table 3.

[0115] Since polyester fibers cannot absorb water and stretch, the resulting fabric has poor water absorption and anti-reverse seepage effects, and is also prone to side leakage.

Claims

1. A knitted fabric, characterized by: The knitted fabric contains a base structure, and at least one side of the knitted fabric is a terry loop or a cut loop. The fibers forming the terry loops and the cut loops contain more than 50 wt% of polyamide composite crimped fibers. The polyamide composite crimped fibers contain 5 to 50 wt% of polyether structural units. In a dry state, the ratio of the height H1 of the terry loops and the cut loops formed by the polyamide composite crimped fibers to the diameter D of the polyamide composite crimped fibers is 1.0 to 15.

0.

2. The knitted fabric according to claim 1, wherein: The height H1 and width L1 of the loops and cut loops formed by the polyamide composite crimped fiber in a dry state, and the height H2 and width L2 of the loops and cut loops formed by the polyamide composite crimped fiber in a wet state satisfy the following relationship: 0.10≤[(H2 / L2)-(H1 / L1)] / (H1 / L1)≤0.70 Formula 1.

3. The knitted fabric according to claim 1 or 2, characterized in that: The height H3 of the bottom structure in a dry state and the height H4 in a wet state satisfy the following relationship: [(H4-H3) / H3]≤0.10 (Equation 2).

4. The knitted fabric according to claim 1 or 2, characterized in that: The knitted fabric has a surface with loops or cut loops, and a ratio of a longitudinal density C to a transverse density W of the surface is greater than 1.

5.

5. The knitted fabric according to claim 1 or 2, characterized in that: The terry loops or cut loops on at least one side of the knitted fabric are all formed by polyamide composite crimped fibers, and the volume V of all the terry loops or cut loops on the terry loop or cut loop surface formed by polyamide composite crimped fibers in the 10 cm×10 cm knitted fabric after absorbing water is 湿润 and the volume before water absorption V 干燥 Satisfies the following relationship, (V 湿润 -V 干燥 )≤5.0cm 3 Formula 3, 6. The knitted fabric according to claim 1 or 2, characterized in that: The single filament fineness of the fibers forming the pile and cut loops is greater than the single filament fineness of the fibers forming the base weave.

7. The knitted fabric according to claim 6, characterized in that: The single-filament fineness of the fibers forming the base structure is less than 1.0 dtex.

8. The knitted fabric according to claim 1 or 2, characterized in that: The thickness of the knitted fabric is less than 4.0 mm, and the water absorption of the knitted fabric of 10 cm×10 cm is greater than 7.0 g / mm.

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