JP7567638B2 - knitting - Google Patents

Description

The present invention relates to a knitted fabric that overcomes the problem of poor snag resistance after repeated washing, which has been an issue with conventional stretch knitted fabrics, and has excellent firmness and a soft feel.

Knitted fabrics have excellent characteristics such as a soft texture and stretchability compared to woven fabrics, and are therefore widely used in various clothing applications such as sports and casual outerwear. In recent years, knitted fabrics using polyurethane yarns and bimetal yarns have been increasingly used to give knitted fabrics even higher stretchability. However, knitted fabrics using polyurethane are suitable for innerwear, but are not suitable for outerwear because they lack firmness and show the body lines too much. In addition, knitted fabrics using conjugate yarns in which different polymers are bonded side-by-side have been proposed (see Patent Document 1). This method certainly produces knitted fabrics with excellent firmness, but the constituent yarns form protruding parts on the fiber surface, and the snag resistance was not taken into consideration at all. Knitted fabrics have a major problem in that they are more susceptible to snags than woven fabrics because the constituent yarns form loops and protrude onto the knitted fabric surface. Various studies have been conducted to improve the snag resistance of knitted fabrics. For example, a method of twisting the yarns that make up the knitted fabric has been proposed to increase the binding force of the yarns that appear on the knitted fabric surface (see Patent Document 2). However, the knitted fabric obtained by the above method had a problem in that the soft texture and stretchability, which are inherent characteristics of the knitted fabric, were lost. In addition, a low-torque composite yarn was obtained by intertwining a yarn made of a false-twisted yarn having a torque in the S direction and a false-twisted yarn having a torque in the Z direction, and a knitted fabric having snag resistance was proposed (see Patent Document 3). This method can certainly produce a knitted fabric having snag resistance, but this effect is only observed before washing, and after repeated washing, the balance of the yarn shape of the two yarns is lost, and one of the yarns tends to protrude from the surface of the knitted fabric, resulting in a decrease in snag resistance. In actual stretch knitted sewn products, the snag resistance often deteriorates after home washing, and a solution to this problem was urgently needed.

JP 2020-186503 A JP 2003-247149 A Patent No. 5155162

The objective of the present invention is to provide a knitted fabric that overcomes the problem of poor snag resistance after repeated washing, which has been an issue with stretch knitted fabrics, and has excellent firmness and a soft feel.

In order to solve the above problems, the knitted fabric of the present invention has the following configuration.
A knitted fabric including a composite false-twisted yarn, the composite false-twisted yarn being composed of a yarn containing a conjugate false-twisted yarn A and a non-conjugate false-twisted yarn B, the composite false-twisted yarn having an entanglement number of 100 or more/m, a torque twist number of 30 T/m or less, and a crimp expression rate difference of 5 to 30%.

The knitted fabric of the present invention is preferably constructed with a composite false-twist yarn having a torque in the S direction and a false-twist yarn having a torque in the Z direction.

In the knitted fabric of the present invention, it is preferable that the conjugate false twist yarn A is composed of polybutylene terephthalate and polyethylene terephthalate.

In the knitted fabric of the present invention, it is preferable that the conjugate false-twist yarn A has an eccentric core-sheath cross section.

It is preferable that the knitted fabric of the present invention has a snag level of 3 or higher after repeated washing.

The present invention makes it possible to eliminate the snag resistance after repeated washing that was previously unattainable, and to obtain knitted fabrics that have excellent firmness and a soft feel.

1 is a photograph substituting a drawing showing an example of a fiber cross section of an eccentric sheath-core composite fiber of the present invention. 1 is a cross-section of an example of an eccentric sheath-core composite fiber of the present invention, illustrating the position of the center of gravity in the fiber cross section. 1 is a fiber cross section for explaining the fiber diameter (D) and minimum thickness (S) in the fiber cross section of an eccentric core-sheath composite fiber of the present invention.

It is important that the knitted fabric of the present invention is made of a composite false-twisted yarn containing at least a conjugate false-twisted yarn A and a non-conjugate false-twisted yarn B. The crimp form differs between the conjugate false-twisted yarn and the non-conjugate false-twisted yarn, and the conjugate false-twisted yarn has a finer coil-like crimp than the non-conjugate false-twisted yarn, so that it can penetrate into the gaps present in the knitted fabric and reduce the gaps in the knitted fabric. By making the yarn in the knitted fabric less mobile, even if an external force is applied to the knitted fabric by repeated washing, the yarn does not protrude from the knitted fabric surface, and excellent snag resistance can be obtained. Here, a knitted fabric made of a single conjugate false-twisted yarn or a composite false-twisted yarn consisting of a conjugate false-twisted yarn and a conjugate false-twisted yarn has excellent stretchability, but the coil crimp is likely to protrude from the knitted fabric surface, and the snag resistance is deteriorated. In addition, when a non-conjugated false-twisted yarn is used alone, or when a composite false-twisted yarn is used that is made up of a non-conjugated false-twisted yarn and a non-conjugated false-twisted yarn, there are many voids in the knitted fabric, and the yarns tend to move with repeated washing, making it easier for the crimps in the outer layer of the yarns to protrude, resulting in poor snag resistance. In addition, when a composite false-twisted yarn is used that is made up of a conjugated non-false-twisted yarn and a non-conjugated false-twisted yarn, residual torque tends to occur, resulting in poor snag resistance.

It is also important that the number of entanglements in the composite false twist yarn constituting the knitted fabric of the present invention is 100 or more per meter. The preferred number of entanglements is 120 to 200 per meter. If the number of entanglements is less than 100 per meter, the crimps in the outer layer of the yarn tend to protrude, the convergent shape cannot be maintained, and snag resistance deteriorates.

It is also important that the torque twist number of the composite false twist yarn constituting the knitted fabric of the present invention is 30 T/m or less. The preferred torque twist number is 20 T/M or less. If the torque twist number exceeds 30 T/M, torque will be generated at the same time as crimping during dyeing processing, resulting in large unevenness in the knitted fabric and poor snag resistance.

It is also important that the difference in crimp expression rate of the composite false-twisted yarns constituting the knitted fabric of the present invention is 5 to 30%. The preferred difference in crimp expression rate is 5 to 20%. If the difference in crimp expression rate is less than 5%, there will be many voids in the knitted fabric, the yarns will be more likely to move with repeated washing, and the crimps in the outer layer of the yarns will be more likely to protrude, resulting in poor snag resistance. If the difference in crimp expression rate exceeds 30%, the non-conjugated false-twisted yarn B will protrude together with the yarns onto the surface of the knitted fabric, resulting in poor snag resistance.

It is also preferable that the composite false-twist yarn constituting the knitted fabric of the present invention is composed of a false-twist yarn having a torque in the S direction and a false-twist yarn having a torque in the Z direction. This preferred embodiment cancels out the false-twist torque and makes the knitted crimp flat, making it easier to obtain excellent snag resistance.

The cross section of the conjugate false twist yarn A used in the present invention is composed of two types of polymers. Suitable polymers for obtaining stretchability include polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polytrimethylene terephthalate, nylon, polylactic acid, thermoplastic polyurethane, and polyphenylene sulfide. The molecular weight of these can be changed to use a high molecular weight polymer for one component and a low molecular weight polymer for the other, or one component can be used as a homopolymer and the other component as a copolymer. In addition, various combinations of different polymer compositions can be mentioned, such as polybutylene terephthalate/polyethylene terephthalate, polytrimethylene terephthalate/polyethylene terephthalate, and polytrimethylene terephthalate/polybutylene terephthalate. Among these, in the combination of polybutylene terephthalate and polyethylene terephthalate, a fine coil crimp structure is developed after false twisting, which reduces the voids in the knitted fabric. This makes it difficult for the knitted fabric to deform with repeated washing, and one of the yarns does not protrude from the knitted fabric surface, resulting in excellent snag resistance, which is preferable.

The ratio of the two components of the conjugate false-twisted yarn A used in the present invention is preferably in the range of A component:B component = 70:30 to 30:70 (area ratio), and more preferably in the range of 65:35 to 45:55.

The cross-sectional shape of the fibers in the conjugate false-twisted yarn A may be any composite cross-sectional shape, whether it is a side-by-side structure or an eccentric sheath-core structure. However, an eccentric sheath-core cross-section is preferred because it reduces cross-sectional deformation during false-twisting, provides uniform crimping in each single yarn, reduces the protrusion of single yarn snarls on the knitted fabric surface, and improves snag resistance.

Here, the eccentric core-sheath cross section refers to a composite cross section formed by bonding two different polymers, in which two polymers with different polymer properties are essentially not separated but exist in a bonded state, and the B component completely covers the A component.

Here, eccentricity refers to the position of the center of gravity of the A component polymer in the cross section of the composite fiber being different from the center of the cross section of the composite fiber. A specific explanation will be given below with reference to FIG. 2. In FIG. 2, the horizontal hatching is the B component, the 30-degree hatching (diagonal lines rising to the right) is the A component, the center of gravity of the A component in the cross section of the composite fiber is center of gravity a, and the center of gravity of the cross section of the composite fiber is center of gravity C. Since center of gravity a and center of gravity C of the cross section of the composite fiber are separated (eccentric), the fiber is greatly curved toward the high shrinkage component after heat treatment. In this way, the high shrinkage component shrinks relatively more strongly than the low shrinkage component, and the eccentric sheath-core composite fiber continues to bend in the fiber axis direction. As a result, the eccentric sheath-core composite fiber has a three-dimensional spiral structure and exhibits good crimp. Here, the more the center of gravity is separated, the better the crimp is exhibited, and good stretch performance is obtained.

The ratio S/D of the minimum thickness S of the B component covering the A component in the eccentric core-sheath cross section (hereinafter referred to as "minimum thickness S") to the fiber diameter (diameter of the composite fiber) D is preferably 0.01 to 0.2, and more preferably 0.02 to 0.08.

This will be explained in more detail using the fiber cross section shown in Figure 3. Here, the thinnest part of component B in the core-sheath composite fiber is the minimum thickness S.

Furthermore, it is preferable that the part having a thickness within 1.05 times the minimum thickness S (hereinafter sometimes referred to as the "minimum thickness part") occupies 1/3 or more of the entire perimeter of the composite fiber. This preferred embodiment means that component A is present along the contour of the fiber, and compared to conventional eccentric core-sheath composite fibers of the same area ratio, the present invention has the centers of gravity of the components farther apart in the fiber cross section, forming a fine spiral and exhibiting good crimp.

More preferably, by setting the perimeter of the thickness within 1.05 times the minimum thickness S to at least 2/5 of the perimeter of the entire fiber, the coil structure of each fiber becomes uniform when crimping occurs, resulting in a knitted fabric with less single-yarn snare and better snag resistance.

The method for measuring the minimum thickness S and fiber diameter D is shown below.

A multifilament made of eccentric sheath-core composite fiber is embedded in an embedding agent such as epoxy resin, and an image is taken of the cross section perpendicular to the fiber direction with a transmission electron microscope (TEM) at a magnification that allows observation of 10 or more fibers (locations). In this case, if metal dyeing is applied, the dye difference between the polymers can be used to clarify the contrast of the joint between the A component and the B component. The presence of the joints makes it possible to confirm that the eccentric sheath-core composite fiber is two-component. A circle circumscribing the cross section of 10 single yarns of eccentric sheath-core composite fiber randomly selected from each image taken, and the circumscribing circle diameter is measured, which corresponds to the fiber diameter D referred to in this invention. The circle circumscribing the cross section referred to here is the true circle that circumscribs the cross section at two or more points most frequently at two or more points on the cross section taken from the two-dimensionally taken image. The circumscribing circle diameter refers to the diameter of the true circle. In addition, the image in which the fiber diameter D was measured is used to measure the minimum thickness of component B covering component A for 10 or more fibers (locations), and the value corresponds to the minimum thickness S referred to in the present invention. Furthermore, these fiber diameters D and minimum thicknesses S are measured in units of μm and rounded off to the nearest third decimal place. The simple number average of the measured values and their ratios (S/D) for the 10 images photographed during the above operation is calculated. Note that the center of specific gravity and the area ratio can be calculated after the area of the entire fiber and the areas of components A and B are calculated using the images photographed above and the image analysis software "WinROOF2015" (Mitani Shoji Co., Ltd.).

The non-conjugate false twist yarn B used in the present invention is not limited as long as it is a thermoplastic polymer that can be false twisted, but polyester, nylon, etc. are particularly preferred. Examples of polyester include polyethylene terephthalate, polybutylene terephthalate, polypropylene terephthalate, and copolymers of these with sulfonic acid components, dicarboxylic acid components, diol components, or oxycarboxylic acid components, or blends of these polyesters. Among them, if the polyester has an anionic site such as a sulfonic acid group, it is preferable because it has cationic dyeability and can express a natural heathered tone due to interaction with a cationic dye having a cationic site. Specific examples of sulfonic acid groups include 5-sulfoisophthalic acid metal salts, such as lithium salts, sodium salts, potassium salts, rubidium salts, and cesium salts, but are not limited to these. Among them, lithium salts and sodium salts are preferred, and sodium salts in particular are preferably used because they have excellent crystallinity.

As for nylon, examples include nylon 6, nylon 66, nylon 610, and nylon 56, but nylon 6 and nylon 66 are particularly preferred because of their excellent crimping properties after false twisting.

In addition, the non-conjugated false twist yarn B used in the present invention can be selected from those having any shape, such as a polygonal cross section, such as a round, triangular, flat, hexagonal, L-shaped, T-shaped, W-shaped, eight-lobed, or dog-bone shape, or a multi-sided shape.

The polymers of the conjugate false-twist yarn A and the non-conjugate false-twist yarn B may contain inorganic fine particles, organic compounds, and carbon black as matting agents such as titanium oxide, flame retardants, lubricants, antioxidants, coloring pigments, etc., as necessary, within the scope of the present invention.

The fineness of the conjugate false-twisted yarn A and the non-conjugate false-twisted yarn B in the present invention is preferably 15 to 150 dtex, which gives the knitted fabric firmness and light weight, while preventing it from becoming too thick when used as an outer garment. The more preferred fineness is 15 to 40 dtex, respectively.

In addition, the single yarn fineness of the conjugate false-twisted yarn A and the non-conjugate false-twisted yarn B in the present invention is preferably 0.3 to 5 dtex, in order to impart stretchability and softness to the knitted fabric. The more preferred single yarn fineness is 0.5 to 3.5 dtex, respectively.

In addition, the ratio of conjugate false-twisted yarn A to non-conjugate false-twisted yarn B in the present invention (A/B: mass ratio) is preferably in the range of 20/80 to 80/20, taking into consideration the balance of crimp development. More preferably, it is in the range of 30/70 to 70/30.

Next, we will explain the manufacturing method of the knitted fabric of the present invention.

First, when spinning the raw yarn of the conjugate false-twist yarn A used in the present invention, if it has an eccentric core-sheath composite structure, it is preferable to precisely control the sheath thickness of the fiber and the perimeter of the thin skin part, and a method using a distribution plate as exemplified in JP-A-2011-174215, JP-A-2011-208313, and JP-A-2012-136804 is preferably used for the spinning nozzle. When manufacturing a composite yarn having an eccentric core-sheath type cross section using a conventionally known composite nozzle, it is often very difficult to precisely control the position of the center of gravity of the core and the sheath thickness. For example, if the sheath thickness becomes thin and the core component is exposed, this can cause a decrease in snag due to the protrusion of single yarn snare on the knitted surface during repeated washing and use, and conversely, if the sheath thickness becomes thick, problems such as a decrease in stretch performance due to a decrease in crimp expression can occur.

In addition, in terms of spinning speed, it is preferable that the amorphous portion is in a highly oriented state in order to improve the crimp expression rate, and the preferred spinning speed is 2,800 to 3,500 m/min.

When spinning the raw yarn for the non-conjugated false twist yarn B used in the present invention, it is also preferable to spin a highly oriented undrawn yarn. In order to improve the crimp expression rate, it is preferable that the amorphous portion is in a highly oriented state, and the preferred spinning speed is 2,800 to 3,500 m/min.

Next, in producing the composite false-twisted yarn used in the present invention, the raw yarn of conjugate false-twisted yarn A and the raw yarn of non-conjugate false-twisted yarn B are false-twisted in different directions (false-twisted in the S direction and false-twisted in the Z direction) and then post-intertwined, which is preferable as it results in a composite yarn with low torque, a flat knitting crimp, and excellent snag resistance.

Any false twist conditions can be selected. The twister may be of the spindle type, friction disk type, or belt nip type, but the friction disk type is preferred because it allows false twisting at high speed and produces relatively little single yarn snare. In the case of a contact heater, the false twist temperature is preferably 170 to 220°C, since it can impart strong crimp. The false twist number is preferably set in the range where the false twist coefficient (false twist number (T/M) x fineness (dtex) ^0.5 ) is 27,000 to 33,000, since it can impart strong crimp. In this case, by setting the false twist coefficient of the conjugate false twist yarn A larger than the false twist coefficient of the non-conjugate false twist yarn B, the fine coil crimp of the conjugate false twist yarn A is more likely to enter inside the crimp of the non-conjugate false twist yarn B, and the gaps present in the knitted fabric can be more effectively filled, which is more preferable.

As for the entanglement conditions, taking into consideration the balance between stretchability and convergence, it is preferable that the entanglement pressure is 0.25 to 0.5 MPa.

The faster the yarn processing speed, the higher the productivity, which is preferable, but when stable processing is taken into consideration, a speed of 100 to 800 (m/min) is preferable.

The knitted fabric of the present invention can be easily knitted using a normal knitting machine. Filaments and spans other than composite textured yarns may be interwoven as long as the object of the present invention is not impaired. The knitted fabric structure is not particularly limited, and may be circular knitted, weft knitted, or warp knitted. Preferred examples of circular knitted and weft knitted structures include plain knitted, flat knitted, rib knitted, double knitted, pearl knitted, tuck knitted, floating knitted, one-sided rib knitted, lace knitted, hair-filled knitted, knit miss, and one-sided knotted. Preferred examples of warp knitted structures include single denby knitted, single atlas knitted, double cord knitted, half tricot knitted, fleece knitted, and jacquard knitted. Among these, circular knitted fabrics are particularly preferred in terms of stretchability. Plain knitted fabrics are preferred in terms of light weight.

The processing step can be carried out according to any dyeing step and conditions. In the knitted fabric of the present invention, it is preferable that the stitch density is within the range of 30 to 100 courses/2.54 cm and 50 to 130 wales/2.54 cm.

In addition, the knitted fabric of the present invention may be subjected to various additional treatments, such as conventional water absorption treatment, water repellency treatment, nap raising treatment, UV protection, or treatments that impart functions such as antibacterial agents, antiviral agents, deodorants, insect repellents, and retroreflective agents, as long as the purpose of the present invention is not impaired.

In addition to the usual snag, the knitted fabric of the present invention preferably has a snag of grade 3 or higher after repeated washing. In conventional stretch knitted fabrics, the yarn shape balance is lost after repeated washing, and yarn stripes may protrude from the knitted fabric surface, resulting in problems with snags. However, by having a snag of grade 3 or higher after repeated washing, the snag resistance of actual stretch knitted sewn products can be further improved.

The stretchability of the knitted fabric of the present invention is preferably 50% or more (preferably 80 to 150%) in the warp and weft directions as measured by method B described in JIS L 1096 (2010).

The knitted fabrics obtained by the present invention are suitable for use as clothing, ranging from casual shirts, sports shirts, and business shirts to skirts, pants, and gym clothes.

The present invention will now be described more specifically with reference to examples.
(1) Fineness: 100 skeins were prepared using a measuring machine with a frame circumference of 1.0 m, and the fineness was measured according to the following formula.

Fineness (dtex) = weight of skein for 100 times (g) x 100
(2) Degree of entanglement The degree of entanglement is the number of entangled parts per meter under a tension of 0.1 cN/dtex. A pin is inserted into the non-entangled part of the yarn under a tension of 0.02 cN/dtex, and the pin is moved up and down in the longitudinal direction of the yarn over 1 m of the yarn under a tension of 0.1 cN/dtex. The part that moves without resistance is regarded as a non-entangled part, and the distance traveled is recorded. The part where the pin stops is regarded as an entangled part. This operation is repeated 30 times, and the degree of entanglement per meter is calculated from the average distance of the non-entangled parts.
(3) Difference in crimp development rate Conjugate false-twist yarn A and non-conjugate false-twist yarn B were carefully loosened and separated from the composite false-twist yarn in the knitted fabric, and 6 cm x 10 pieces of each were taken out as samples. The samples were marked at intervals of 5 cm (L ₁ ) under a load of 1 mN/dtex, wrapped in gauze, and heat-treated in boiling water at 100°C for 30 minutes under no tension. The samples were then taken out and air-dried at 35°C and 60% RH for 24 hours, and the intervals (L) marked after heat treatment were read under a load of 0.02 mN/dtex. This process was repeated 10 times, and the average value was taken as the crimp development rate. Furthermore, the difference in crimp development rate was calculated using the following formula.

Shrinkage development rate (%)={(L−L ₁ )/L}×100
Crimp development rate difference (%) = (crimp development rate of conjugate false-twisted yarn A) - (crimp development rate of non-conjugate false-twisted yarn B)
(4) Torque and twist number Approximately 75 cm of composite false twist yarn is stretched horizontally, and an initial load of 0.02 mN/dtex is hung from the center, and then both ends are aligned. The yarn begins to rotate due to the residual torque, but is held in this state until the initial load stops, obtaining a twisted yarn. The twist number of a 25 cm length of the twisted yarn thus obtained is measured with a twist detector under a load of 1 mN/dtex. The obtained twist number (T/25 cm) is multiplied by 4 to obtain the torque (T/m).
(5) Stretch rate (%)
The elongation rate was measured under a load of 1.5 kgf (14.7 N) according to Method B described in JIS L 1096 (2010).
(6) Snag Resistance Evaluation The washing cycle was performed once using a two-tub washing machine with a liquid temperature of 40°C, a washing time of 5 minutes, rinsing at 30°C for 2 minutes twice, and spinning for 30 seconds. Kao's "Attack" (registered trademark) was used as the detergent at 1 g/L, the liquid volume was 40 L, and the combined weight of the test cloth and the cotton cloth used as the guide cloth was 830 g. After repeating this washing operation 20 times, the grade was determined according to the JIS L 1058 (2010) D-1 method.
A passing grade is 3.5 or above.
(7) Firmness In a sensory evaluation, waist firmness was evaluated on a four-point scale: very good waist firmness, good waist firmness, slightly insufficient waist firmness, and insufficient waist firmness. The result was determined to be closest to the average of the ratings of 10 randomly selected persons.
(8) Softness: In a sensory evaluation, softness was rated on a four-point scale: very excellent softness, excellent softness, slightly insufficient softness, and insufficient softness. The result was determined to be closest to the average of the ratings of 10 randomly selected panelists.

Example 1
Polyethylene terephthalate and polybutylene terephthalate were fed into a spinneret for eccentric sheath-core composite fiber with a weight composite ratio of 50/50 and 48 discharge holes. The polymers were joined inside the spinneret to form an eccentric sheath-core composite form in which the A component polymer was contained in the B component polymer, and the resulting fiber was spun from the spinneret at a spinning speed of 3,000 (m/min) to obtain a conjugate partially oriented yarn with a fineness of 56 dtex, 48 filaments, and an elongation of 130%. In the spinning of Example 1, a distributor type spinneret was used to obtain the eccentric sheath-core composite fiber shown in Figure 1. The S/D ratio in the fiber cross section was 0.02, and the minimum thickness portion occupied 40% of the fiber circumference.

Next, polyethylene terephthalate having a circular cross section copolymerized with 0.3 mol % of 5-sodium sulfoisophthalic acid was spun at a spinning speed of 3,000 (m/min) to obtain a polyethylene terephthalate partially oriented yarn having a fineness of 56 dtex, 48 filaments and an elongation of 145%.

Then, using a friction false twisting machine, the conjugate partially oriented yarn was false twisted in the S direction at a stretch ratio of 1.7 times and a false twist coefficient of 29,000 at a processing speed of 400 m/min and a heater temperature of 180°C, and the polyethylene terephthalate partially oriented yarn was false twisted in the Z direction at a stretch ratio of 1.8 times and a false twist coefficient of 28,000.Then, an interlacing process was performed at an interlacing pressure of 0.4 MPa, resulting in a composite textured yarn with a fineness of 64 dtex, interlacing number of 125/m, and a torque twist number of 2 T/m (S direction).

Next, the composite false twist yarn was used to knit a plain knitted circular fabric on a 36G single circular knitting machine. The resulting greige fabric was subjected to continuous open scour at 98°C, dyed navy blue at 120°C using a cationic dye, and then finished and set at 170°C to obtain a knitted fabric with a basis weight of 98g/ ^m2 , 98 courses/2.54cm, 58 wales/2.54cm, and a crimp development rate difference of 18% (conjugate: 48%, non-conjugate: 30%).

The resulting knitted fabric had a warp stretch rate of 78% and a weft stretch rate of 110%, and its snag resistance rating was 4.5 before washing and 4 after 20 washes. Even after repeated washing over a long period of time, the knitted fabric had excellent snag resistance, softness, and firmness.

Example 2
In the same manner as in Example 1, a conjugate partially oriented yarn having a fineness of 56 dtex, 48 filaments and an elongation of 130% was obtained.

Next, the round cross-section nylon 66 was spun at a spinning speed of 3,200 (m/min) to obtain a nylon 66 drawn yarn with a fineness of 30 dtex, 26 filaments, and an elongation of 60%.

Then, using a friction false twisting machine, the conjugate partially oriented yarn was false twisted in the S direction at a stretch ratio of 1.7 times and a false twist coefficient of 29,000 at a processing speed of 400 m/min and a heater temperature of 180°C, and the nylon 66 stretched yarn was false twisted in the Z direction at a stretch ratio of 1.1 times and a false twist coefficient of 28,500.Then, an interlacing process was performed at an interlacing pressure of 0.45 MPa, resulting in a composite textured yarn with a fineness of 60 dtex, interlacing number of 155 pieces/m, and a torque twist number of 5 T/m (S direction).

Next, the composite false twist yarn was used to knit a plain knitted circular fabric on a 36G single circular knitting machine. The resulting greige fabric was subjected to continuous open scour at 98°C, dyed navy blue at 100°C using an acid dye, and further given a finish set at 170°C to obtain a knitted fabric with a basis weight of 96g/ ^m2 , 102 courses/2.54cm, 61 wales/2.54cm, and a crimp development rate difference of 13% (conjugate: 48%, non-conjugate: 35%).

The resulting knitted fabric had a warp stretch rate of 85% and a weft stretch rate of 122%, and its snag resistance rating was 4.5 before washing and 4 after 20 washes. Even after repeated washing over a long period of time, the knitted fabric had excellent snag resistance, softness, and firmness.

Example 3
The component A was polyethylene terephthalate and the component B was polytrimethylene terephthalate. The weight composite ratio of the components A and B was 50/50. The components were spun from a side-by-side spinneret having 48 nozzles at a spinning speed of 3,000 (m/min) to obtain a conjugate partially oriented yarn having a fineness of 90 dtex, 48 filaments and an elongation of 128%.

Next, the polyethylene terephthalate with a circular cross section was spun at a spinning speed of 3,000 (m/min) to obtain a partially oriented polyethylene terephthalate yarn with a fineness of 56 dtex, 48 filaments, and an elongation of 143%.

Then, using a friction false twisting machine, the conjugate partially oriented yarn was false twisted in the S direction at a stretch ratio of 1.7 times and a false twist coefficient of 29,000 at a processing speed of 400 m/min and a heater temperature of 180°C, and the polyethylene terephthalate partially oriented yarn was false twisted in the Z direction at a stretch ratio of 1.8 times and a false twist coefficient of 29,500.Then, an interlacing process was performed at an interlacing pressure of 0.25 MPa, resulting in a composite textured yarn with a fineness of 94 dtex, interlacing number of 104/m, and a torque twist number of 3 T/m (S direction).

Next, the composite false twist yarn was used to knit a plain knitted circular fabric on a 36G single circular knitting machine. The resulting greige fabric was subjected to continuous open scour at 98°C, dyed navy blue at 130°C using a disperse dye, and further given a finish set at 170°C to obtain a knitted fabric with a basis weight of 118g/ ^m2 , 82 courses/2.54cm, 51 wales/2.54cm, and a crimp development rate difference of 6% (conjugate: 42%, non-conjugate: 36%).

The resulting knitted fabric had a warp stretch rate of 72% and a weft stretch rate of 104%, and its snag resistance rating was grade 4 before washing and grade 3.5 after 20 washes. Even after repeated washing over a long period of time, the knitted fabric had excellent snag resistance, softness, and firmness.

<Comparative Example 1>
In the same manner as in Example 1, two conjugate partially oriented yarns having a fineness of 56 dtex, 48 filaments and an elongation of 130% were obtained.

The two conjugate partially oriented yarns were then false-twisted in the S direction and Z direction, respectively, using a friction false-twisting machine at a processing speed of 400 m/min, a heater temperature of 180°C, a stretch ratio of 1.7 times, and a false-twist coefficient of 29,000.Then, they were interlaced at an interlacing pressure of 0.4 MPa to obtain a composite textured yarn with a fineness of 66 dtex, interlacing number of 124/m, and a torque twist number of 2 T/m (S direction).

Next, the composite false twist yarn was used to knit a plain knitted circular fabric on a 36G single circular knitting machine. The resulting greige fabric was subjected to continuous open scour at 98°C, dyed navy blue at 120°C using a disperse dye, and further given a finish set at 170°C to obtain a knitted fabric with a basis weight of 107g/ ^m2 , 105 courses/2.54cm, 63 wales/2.54cm, and a crimp development rate difference of 0%.

The resulting knitted fabric had a warp stretch rate of 87% and a weft stretch rate of 134%, and its snag resistance rating was 3.5 before washing and 2.5 after 20 washes, meaning that the snag resistance decreased with repeated washing. It also had excellent softness, but was somewhat lacking in firmness.

<Comparative Example 2>
Polyethylene terephthalate having a circular cross section was spun at a spinning speed of 3,000 (m/min) to obtain two polyethylene terephthalate partially oriented yarns having a fineness of 56 dtex, 48 filaments and an elongation of 145%.

Then, using a friction false twisting machine, at a processing speed of 400 m/min and a heater temperature of 180°C, one of the polyethylene terephthalate partially oriented yarns was false twisted in the S direction with a stretch ratio of 1.7 times and a false twist coefficient of 29,000, and the other polyethylene terephthalate partially oriented yarn was false twisted in the Z direction with a stretch ratio of 1.8 times and a false twist coefficient of 28,000, and then interlaced at an interlacing pressure of 0.4 MPa to obtain a composite textured yarn with a fineness of 64 dtex, interlacing number of 118/m, and a torque twist number of 2 T/m (S direction).

Next, the composite false twist yarn was used to knit a plain knitted circular fabric on a 36G single circular knitting machine. The resulting greige fabric was subjected to continuous open scour at 98°C, dyed navy blue at 130°C using a disperse dye, and then finished at 170°C to obtain a knitted fabric with a basis weight of 98g/ ^m2 , 85 courses/2.54cm, 53 wales/2.54cm, and a crimp development rate difference of 3%.

The resulting knitted fabric had a warp stretch rate of 43% and a weft stretch rate of 77%, and its snag resistance rating was 4.5 before washing and 2.5 after 20 washes, meaning that the snag resistance decreased with repeated washing. It also had a slightly insufficient softness and insufficient firmness.

<Comparative Example 3>
In the same manner as in Example 1, two conjugate partially oriented yarns having a fineness of 56 dtex, 48 filaments and an elongation of 130% were obtained.

The two conjugate partially oriented yarns were then false-twisted in the S direction using a friction false-twisting machine at a processing speed of 400 m/min, a heater temperature of 180°C, a stretch ratio of 1.7 times, and a false-twist coefficient of 29,000.Then, they were interlaced at an interlacing pressure of 0.4 MPa to obtain a composite textured yarn with a fineness of 66 dtex, interlacing number of 132/m, and a torque twist number of 42 T/m (S direction).

Next, the composite false twist yarn was used to knit a plain knitted circular fabric on a 36G single circular knitting machine. The resulting greige fabric was subjected to continuous open scour at 98°C, dyed navy blue at 120°C using a disperse dye, and further given a finish set at 170°C to obtain a knitted fabric with a basis weight of 110g/ ^m2 , 104 courses/2.54cm, 62 wales/2.54cm, and a crimp development rate difference of 0%.

The resulting knitted fabric had a warp stretch rate of 88% and a weft stretch rate of 138%, and its snag resistance rating was grade 3 before washing and grade 1.5 after 20 washes. Repeated washing caused the unevenness of the knitted fabric surface to increase, and snag resistance to decrease. It also lacked softness and had some lack of firmness.

<Comparative Example 4>
In the same manner as in Example 1, a conjugate partially oriented yarn having a fineness of 56 dtex, 48 filaments and an elongation of 130% was obtained.

Next, the polyethylene terephthalate with a circular cross section was spun at a spinning speed of 3,000 (m/min) to obtain a partially oriented polyethylene terephthalate yarn with a fineness of 56 dtex, 48 filaments, and an elongation of 143%.

Then, using a friction false twisting machine, the conjugate partially oriented yarn was false twisted in the S direction with a stretch ratio of 1.7 times and a false twist coefficient of 29,000 at a processing speed of 400 m/min and a heater temperature of 180°C, and the polyethylene terephthalate partially oriented yarn was false twisted in the Z direction with a stretch ratio of 1.8 times and a false twist coefficient of 29,500.Then, an interlacing process was performed with an interlacing pressure of 0.2 MPa to obtain a composite textured yarn with a fineness of 93 dtex, interlacing number of 85/m, and a torque twist number of 10 T/m (S direction).

Next, the composite false twist yarn was used to knit a plain knitted circular fabric on a 36G single circular knitting machine. The resulting greige fabric was subjected to continuous open scour at 98°C, dyed navy blue at 120°C using a cationic dye, and then finished at 170°C to obtain a knitted fabric with a basis weight of 106g/ ^m2 , 95 courses/2.54cm, 56 wales/2.54cm, and a crimp development rate difference of 22% (conjugate: 48%, non-conjugate: 26%).

The resulting knitted fabric had a warp stretch rate of 80% and a weft stretch rate of 115%, and a snag resistance rating of 4.5 before washing and 2.5 after 20 washes. The fabric had excellent softness and firmness, but repeated washing caused the interlacing to come undone, single yarns to protrude from the knitted fabric surface, and snag resistance to decrease.

The knitted fabric of the present invention can be suitably used for clothing applications ranging from casual shirts, sports shirts, and business shirts to skirts, pants, and gym clothes.

1 A component 2 B component a Center of gravity of A component C Center of gravity of composite fiber cross section D Fiber diameter S Minimum thickness

Claims (5)

A knitted fabric containing a composite false-twisted yarn, the composite false-twisted yarn being made of a yarn containing conjugate false-twisted yarn A and non-conjugate false-twisted yarn B, the composite false-twisted yarn having an entanglement number of 100 or more/m, a torque twist number of 30 T/m or less, and a difference in crimp occurrence rate of 5 to 30%. The knitted fabric according to claim 1, characterized in that the composite twisted yarn is composed of a twisted yarn having torque in the S direction and a twisted yarn having torque in the Z direction. The knitted fabric according to claim 1 or 2, characterized in that the conjugate false twist yarn A is composed of polybutylene terephthalate and polyethylene terephthalate. The knitted fabric according to any one of claims 1 to 3, characterized in that the conjugate false-twist yarn A has an eccentric core-sheath cross section. The knitted fabric according to any one of claims 1 to 4, characterized in that the snag after repeated washing is grade 3 or higher.

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