JP2000314054A - Cool touch knit fabric - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cool touch knit fabric capable of imparting cool and comfort in moving a hot environment by knitting a specific knit fabric including long fiber threads having a specific gravity of equal to or larger than a specific value and having specific values of degree of fiber packing, damping factor of the knit fabric and air permeability, respectively. SOLUTION: This cool touch knit fabric is provided by knitting a knit fabric having a ground weave of long fiber threads and including >=25 wt.% of the long fiber threads such as cellulose long fiber threads and the likes having >=1.4 specific gravity and in which preferably the aforesaid long fiber threads comprises the long fiber threads having >=1.4 specific gravity, 7-150 degree of packing X of the fiber defined by X= [course number (number/inch) of the ground weave]+[number of well (number/inch)]}×[crimp elongation(%) of the fiber threads constituting the grand weave]÷(denier of the fiber threads constituting the grand weave)1/2, <=3 vibrational damping factor Y expressed by Y=2HG (gf/cm)/G1/2(gf/cm.deg) (2HG is a shear hysteresis; G is a shear rigidity) and 80-250 cc/cm2.s air permeability.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cool knitted fabric, and more particularly to a sports shirt worn for a long time such as tennis, soccer, volleyball, table tennis, and long-distance running. The present invention relates to a knitted fabric that can provide refreshing comfort when exercising in a hot environment.

[0002]

2. Description of the Related Art When a large amount of sweat is generated by exercise in the heat, if the sweat cannot be effectively evaporated, the sweat will wet on the skin, soothe the skin and close the sweat glands.
The result is the hydromeiosis phenomenon,
When this phenomenon occurs, the sweating action does not work properly, so that human body temperature rise is unavoidable. When body temperature rises, it becomes hot and uncomfortable, and exercise endurance drops significantly.

Conventionally, a sweat treatment function in a functional shirt,
Improvement of refreshing property and wearing comfort can be achieved by using hydrophilic fibers, making the fibers hydrophilic so that the fibers have water absorption, and increasing the water absorption by utilizing the capillary phenomenon caused by the effect of the cross-sectional shape of the fibers (Japanese Patent Publication No. JP-A-80217), increasing the water absorption by changing the knitting density between the skin side and the outside air side of the knitted fabric (Japanese Patent Laid-Open No. 9-41245), and preventing the fabric and the skin side from sticking by making the texture uneven. It is performed by a method of improving the contact cooling sensation and the heat radiation in consideration of the thermal conductivity of the fiber. However, these methods are designed based on the performance of the knitted fabric in a static steady state, and do not take into consideration that the knitted fabric moves with human motion.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to take into consideration the above-mentioned problems of the prior art and to reduce the heat generated by exercise due to the ventilation effect caused by the vibration and swinging motion of a shirt or the like during actual exercise. Cooling and wearing comfort that can be effectively released out of clothing and the heat of evaporation removed at that time can lower the average skin temperature of the wearer, reduce heat and improve exercise endurance It is to provide an excellent refreshing knitted fabric.

[0005]

Means for Solving the Problems The present inventors diligently studied the above-mentioned problems, and examined the type, density, structure, structure, etc. of the fibers constituting the knitted fabric, and the wearing test when the knitted fabric was used as a shirt. From the relationship between physiological data and wearing comfort by
When the knitted fabric is worn as a shirt or the like by specifying the structure of the knitted fabric, improving the swaying motion of the knitted fabric, and further reducing the vibration damping rate of the knitted fabric, the heat production of the wearer Have been found to be able to effectively deprive the skin by ventilation due to the vibration and shaking movement of the shirt, lower the average skin temperature, and enhance the refreshability and wearing comfort, and have reached the present invention. That is, the invention claimed in the present application is as follows.

(1) A knitted fabric having a ground structure using long fiber yarns, wherein the knitted fabric contains 25% by weight or more of long fiber yarns having a specific gravity of 1.4 or more and the following formula (1) The X value representing the fiber filling degree of the ground structure defined by) is 7 to 150, and the following formula (2)
A cool knitted fabric, characterized in that the Y value representing the vibration damping rate of the knitted fabric defined by the following is 3 or less, and the air permeability of the knitted fabric is 80 to 250 cc / cm ² · s. X = {number of courses of ground structure (pieces / inch) + number of wale (pieces / inch)} x crimp elongation rate (%) of fiber yarns constituting the ground structure ÷ 繊 維 denier fiber yarns forming the ground structure (D) (1) Y = 2HG (gf / cm) / ΔG (gf / cm · deg) (2) (2HG is shear hysteresis and G is shear rigidity) (2) The specific gravity of the ground structure The cool knitted fabric according to (1), wherein the knitted fabric is composed of 1.4 or more long fiber yarns. (3) The cool knitted fabric according to (1) or (2), wherein the long fiber yarn having a specific gravity of 1.4 or more is a cellulose long fiber yarn.

Hereinafter, the present invention will be described in detail.
The cool knitted fabric in the present invention utilizes the fact that the shirt vibrates due to the movement of the human body, especially when the shirt is worn during exercise, and the vibration and swinging motion of the knitted fabric due to the movement causes ventilation and heat exchange in the clothes. Is carried out smoothly, and the heat of evaporation of sweat is efficiently taken away, so that an increase in skin temperature can be suppressed and refreshing comfort can be provided.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The cool knitted fabric according to the present invention is a knitted fabric having a ground structure using long fiber yarns, and 25% by weight of long fiber yarns having a specific gravity of 1.4 or more in the knitted fabric. And more preferably 40% by weight or more. By using long fiber yarns for the ground structure, the stitches of the ground structure are more likely to shift and move more easily than when short fiber yarns are used, so that a knitted fabric that swings easily due to the movement of the human body can be obtained. . The specific gravity referred to in the present invention means a density gradient tube method (JIS-L-101).
It is measured according to 3). Here, the ground structure is a structure basically formed by a series of knit loops, such as a sheet of knitted fabric, a rubber knit, etc. for a weft knit, a denbi, a cord, etc. for a warp knit, and is a basic tensile strength of a knitted fabric. It controls physical properties such as elongation and bending rigidity, and refers to a tissue portion where a knitted fabric is formed by itself. In addition, a structure that cannot form a knitted fabric alone such as a pile structure or a floating yarn structure is not included, but a tack loop or a welt loop may be partially included in a series of knit loops.

[0009] As a long fiber yarn used for the ground structure,
Examples include synthetic fibers such as polyester, nylon, and acrylic; regenerated cellulose fibers such as cupra, rayon, acetate, polynosic, and lyocell; and purified cellulose fibers. The forms of these long fiber yarns include raw yarn, processed yarn (false twist, interlace processing, fluid disturbance processing, twisted yarn, etc.) and composite processed yarn (interlace mixed fiber, fluid disturbance processing, composite false twist, ply twist, etc.). Either may be used. The ground structure may include a long fiber yarn, for example, a ground structure using a yarn obtained by compounding a long fiber yarn and a short fiber yarn (twisting, spinning, twisting, etc.), The ground structure may be formed by knitting long fiber yarns and short fiber yarns. When the ground structure is composed of a composite yarn of long fiber yarn and short fiber yarn, or when the knitted structure of long fiber yarn and short fiber yarn is used, the usage ratio of long fiber yarn in the ground structure is 30% by weight. %, More preferably 40% by weight or more. The cross-sectional shape of the long fiber yarn is not particularly limited, and may be round, triangular, Y-shaped, or L-shaped.
The shape may be any shape such as a mold, a W shape, a flat shape, a dog bone shape, and a multi-leaf shape.

[0010] In addition, the weight of the knitted fabric is increased by including 25 wt% or more of the long fiber yarn having a specific gravity of 1.4 or more in the knitted fabric,
At the same time as the momentum during vibration increases, the vibration damping rate decreases, and the vibration continues for a long time, resulting in a knitted fabric that can exhibit an excellent ventilation effect. The long fiber yarn having the specific gravity may be arranged in the ground structure of the knitted fabric or may be arranged in a structure other than the ground structure. However, when it is arranged in the ground structure, the momentum due to vibration is further improved. From this point, it is more preferable that the ground structure is constituted by long fiber yarns having a specific gravity of 1.4 or more.

For the long fiber yarn having a specific gravity of 1.4 or more, the above-mentioned synthetic fiber or cellulose fiber can be used.
In the case of synthetic fibers, for example, polyester fibers (specific gravity 1.
38) containing a metal oxide, a pigment or the like in an amount of 1% by weight or more and a specific gravity of about 1.4 to 1.42. Further, it is preferable that the fiber has an elliptical shape or a flat cross section such as W or M, since the bending softness is improved and the fiber is easily vibrated. Cellulose fibers such as rayon and cupra are more preferable because the specific gravity is as high as about 1.5. For example, a fiber in which a metal oxide, a pigment, and the like are contained in a cellulose long fiber in an amount of 0.8% by weight or more has a specific gravity of about 1.53, and the vibration damping rate of the knitted fabric is reduced. The use of cellulose fibers is preferable because the hygroscopicity is further improved and the cooling effect is further improved.

In the knitted fabric of the present invention, in addition to long fiber yarns and short fiber yarns made of the above-mentioned materials, cotton, wool,
Natural fibers such as silk can be used. These are used as composite yarns or by mixing and knitting them. When a spun yarn is used, it is preferable to use a spun yarn having a relatively long short fiber length and a densely spun fiber with a high twist coefficient in order to satisfy a Y value which is an important factor in the present invention described later. The thickness of the fiber constituting the knitted fabric is not particularly limited as long as it is a thickness used for general clothing, and is preferably 30 d to 300 d for a multifilament and 20 s to 80 s (cotton count) for a spun yarn. .

The knitted fabric of the present invention is represented by the relationship between the denier of the fiber yarns constituting the ground structure, the crimp elongation rate of the fiber yarns, and the density of the ground structure. X value representing the degree of fiber filling of the ground structure to be defined is 7 to 150,
Preferably, it is required to be 7 to 120. This X
If the value exceeds 150, that is, if the sum of the number of courses and the number of wales with respect to the thickness of the yarn is too large, the stitches are too tight, the knitted fabric becomes bulky, the swinging motion is reduced, and the ventilation is difficult to cool. The knitted fabric lacks. On the other hand, when the X value is 7
If it is less than, that is, if the sum of the number of courses and the number of wales is too small with respect to the thickness of the yarn, the gap of the stitch becomes large, it becomes easy to swing, and the freshness by ventilation is improved, but the stitch becomes loose. If it is too large, physical properties such as snags are reduced, resulting in a knitted fabric unsuitable for shirt products and the like.

The crimp elongation percentage of the fiber yarn constituting the ground structure is preferably 1.5 to 20%, more preferably 1.5 to 15%. If the crimp elongation is too small, the stitches of the ground structure are slippery, and the physical properties of the knitted fabric, such as snags, are likely to be reduced. Ease is likely to decrease. Also, if the crimp elongation is too large, the density of the ground structure must be reduced more than necessary in order to obtain the swaying motion of the knitted fabric, and conversely, the stitches become too loose and physical properties such as snags are likely to be reduced. . Here, the crimp elongation rate of the fiber yarns constituting the ground structure is, when the ground structure is composed of a composite yarn of long fiber yarns or a composite yarn of long fiber yarn and short fiber yarn, Indicated by crimp elongation rate, 2
When fiber yarns having more than one kind of crimp elongation overlap to form a knit loop of ground structure, the average value of the crimp elongation of each fiber yarn (weight mixing ratio of each fiber yarn) (%) And the product of the crimp elongation rate is summed up and divided by 100).

As a method for reducing the crimp elongation rate of the fiber yarn constituting the ground structure, a set twist number is reduced by false twisting, a false twist temperature is reduced, a two-heater processed yarn, or a combination thereof is used. And the like. When bulkiness is imparted by interlace processing, fluid disturbance processing, twisting yarn, or the like other than false twisting processing, a yarn having bulkiness, that is, crimp elongation, can be suppressed to an appropriately low level. A method may be used in which a fiber yarn having a high bulkiness and a fiber yarn having a low bulk are combined by interlace blending or ply twisting to suppress the total crimp elongation rate of the composite yarn. The denier of the fiber yarns constituting the ground structure is the sum of the deniers of the fiber yarns when two or more types of fiber yarns are overlapped by pulling and knitting to form a knit loop of the ground structure. In the case where two or more types of fiber yarns form knit loops having different ground structures by cross knitting or the like, the average value of the denier of each fiber yarn (weight mixing ratio of each fiber yarn) (%) And the product of denier is summed and divided by 100).

Further, the cool knitted fabric according to the present invention has the above formula
The Y value representing the vibration damping rate of the knitted fabric defined by (2) is 3 or less, and preferably ranges from 2 to 3. This Y value is 3
In the following, the vibration of the knitted fabric continues for a long time, the heat exchange and ventilation are performed smoothly, the transpiration of sweat works effectively, and the human body heat can be efficiently dissipated, resulting in a rise in skin temperature. Can be suppressed. When the Y value exceeds 3, the vibration does not last for a long time, heat exchange and ventilation are not performed smoothly, and the average skin temperature is increased. Further, the knitted fabric of the present invention has an air permeability of 80 to 250, preferably 100 to 2.
00 range. If the air permeability of the knitted fabric is less than 80, heat exchange by ventilation is not sufficiently performed when the knitted fabric is used as a shirt during exercise, so that a cool shirt is not obtained. Also 250
When it exceeds, the cooling property by ventilation is improved, but the voids of the stitches become too large and the stitches become too loose, resulting in a decrease in physical properties such as snags and the like, which makes the knitted fabric unsuitable for shirt products.

In the present invention, the knit structure of the knitted fabric is not particularly limited, and may be a weft knit such as a sheet knit or a rubber knit, a warp knit such as a denbi structure or a cord structure, a single knit or a double knit. Basically, it is sufficient that the ground structure formed by connecting the knit loops forms the basic structure of the knitted fabric. The knitted fabric may be constituted by the ground structure alone, or may be combined with other structures (pile structure, floating yarn structure, etc.). The proportion of the ground structure in the knitted fabric is preferably 40% by weight or more from the viewpoint of improving the easiness of swinging movement of the knitted fabric. The knitting structure may have a single-layer structure or a multilayer structure.

The multilayer structure referred to here is a structure in which two or more types of structures are apparently superposed in a layer state to form a single knitted fabric.
Refers to a structure in which more than one kind of fiber is formed in a layer structure,
A structure having unevenness or a pile structure can be combined on the surface opposite to the ground structure of the knitted fabric, or a multilayer structure in which the front and back surfaces of the knitted fabric are made of different fibers can be used. Further, a knitted structure having a stretch property in which elastic fibers such as spandex are combined can be used. A preferred knitting structure has a plain structure with no unevenness on the knit loop surface of the knitted fabric, so that vibrations are transmitted evenly and are likely to last for a long time. More preferably, the knitted fabric has a structure in which both surfaces of the knitted fabric form a plain knit loop.

[0019]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. The scouring, water absorption, and final setting of the polyester knitted fabric and polyester / cellulose composite knitted fabric used in the examples were performed by the following methods. (1) Refining temperature × time 80 ° C × 20 min Refining agent Score roll (manufactured by Kao) 2 g / L (2) Water absorption temperature × time 95 ° C × 30 min Water absorbing agent SR-1805M (Takamatsu oil and fat) 5% owf (ester) ( 3) Final set temperature x time 180 ℃ x 0.5min

The physical properties of the yarn, the amount of the knitted fabric, the knitted fabric properties, and the wearing comfort were measured or evaluated by the following methods, and the results are shown in Table 1. (I) Measurement of Yarn Physical Properties Crimp Elongation: Based on JIS-L-1090 Synthetic Fiber Bulky Processed Yarn Test Method, 5.7 Stretching Method B Method. (Ii) Measurement of knitted fabric properties and knitted fabric characteristics After the knitted fabric was stored in a constant temperature room maintained at 20 ° C. and 65% environment for 24 hours, the measurement was similarly performed in the constant temperature room. The air permeability and KES were measured by cutting into a 20 cm square. Shear rigidity G (gf / cm · deg): Measurement was performed with high sensitivity using KES-F1 manufactured by Kato Tech. However, it was measured at φ = 0.5 °. The numerical value used the average value of the process. Shear hysteresis was measured in the same manner as in 2HG (gf / cm). The numerical value used the average value of the process. Air permeability (cc / cm ² · s): JIS-L-1096
(Method A air flow method). Bending rigidity B (gf · cm ² / cm) of the knitted fabric is measured in the same manner as described above, and is used as a substitute value for the ease of the swinging movement. Snag (grade): JIS-L-1058 (Freening method 5 hours)

(Iii) Evaluation of Wearing Comfort The knitted fabric was sewn on a shirt. Next, wear a monitor (height 17)
Ten (5 cm ± 5 cm male, age 19 to 23, belonging to the university athletic club tennis club, standard body type) were selected, and one monitor shirt was distributed one day a day with details down on each monitor. Each monitor was rested in a preliminary test room at 25 ° C. and 65% for 15 minutes, and moved to a test room at 30 ° C. and 70%. After changing clothes (underwear is 100% cotton
% Underwear, ester / cotton = 65/35 tennis shorts, and cotton / polyurethane socks. ) 5mi
Rest in n-sitting position and exercise for 20 min with a room runner set at 10 km / h, then 5 min
The test was completed after sitting in a sitting position. At the time of changing clothes, a thermocouple temperature sensor is attached to the right chest, upper arm, thigh, and lower leg of the monitor at a predetermined position with a bandage, and the temperature is set every 20 seconds from the start of rest before exercise to the end of rest after exercise. Captured data. Among the data, data from the start of exercise to the end of exercise were averaged for each sample for each person (for example, monitor A). The average skin temperature was standardized by taking the standard deviation of each person (for example, monitor A) based on the data of all the samples of each person in consideration of individual differences.
The data for the standardization was calculated as follows. Here, an example is shown assuming that calculation is performed for samples 1 to 5 of the monitor A.

Average skin temperature of sample 1 (normalized data)
_{= (Z 1 -X 1-5) /} Y 1-5 except X _1-5 Monitor A mean of samples 1 to 5 skin temperature average value Y _1-5 Monitor A Average skin temperature of the sample 1-5 of the Standard deviation Z ₁ Average value of ₁ sample 1 In addition, the questionnaire for wearing is requested to report the score of the heat every 1 minute from the rest before exercise, and the scores are averaged from the start of exercise to the stop of exercise, and the standard of scoring. Did the following: Comfortable (5 points): Very cool with little sweat. Slightly comfortable (4 points): A little sweaty on the side, but cool. Slightly uncomfortable (3 points): Slightly hot and uncomfortable with sweat on the forehead, hands, and neck. Discomfort (2 points): Very hot and uncomfortable with sweat flowing. Very uncomfortable (1 point): A lot of sweat flows and it is very hot and uncomfortable.

Examples 1 and 2 and Comparative Example 1 Polyester long fibers (75d / 36f) containing 4.0% by weight of titanium oxide and having a specific gravity of 1.41 and titanium oxide were added in an amount of 1.
Cupra long fibers (50% specific gravity containing 3% by weight)
d / 30f) using a 33H air jet crimper manufactured by Murata Machine Co., Ltd. at the same time with a yarn speed of 250 m / min, an overfeed ratio of cupra filaments of 8.57%, and an overfeed ratio of polyester filaments of 17.17%. The mixture was supplied to a nozzle and subjected to composite fluid disturbance processing at an air pressure of 5.0 kg to obtain a polyester / cupra composite fiber having a crimp elongation of 1.6%. The two polyester / cupra composite yarns were aligned and the stitches were changed to three levels using a 24-gauge single circular knitting machine to produce three types of sheet-knit fabrics having different densities. All are 100% polyester / cupra composite yarn
It is a knitted fabric forming a ground structure.

The greige machine of three levels performs scouring and water absorption processing,
The tentering rate was changed in the final set according to the density of the greige, and knitted fabrics I, II, and VI having different X values, Y values, and air permeability were obtained. These knitted fabrics were sewn on a shirt and subjected to a monitor wearing test. The results are shown in Table 1.
Since the value, Y value and air permeability are in the proper range, all of them are easy to shake and the average skin temperature (standardized data) is low.
Also, the wearing questionnaire score was high, and the fabric was very refreshing and comfortable. However, in the knitted fabric VI, since the X value was low and the Z value was too high, the physical properties of the snug were very poor.

Example 3 Polyester long fiber (125d / 60f) containing 0.1% by weight of titanium oxide and having a specific gravity of 1.38 was rotated with a Mitsubishi LS-2 false twister at a spindle rotation of 250,000 rpm and a twist of 260.
At 0 T / m, the first heater temperature was set to 200 ° C., the second heater temperature was set to 190 ° C., and the overfeed rate in the second heater zone was set to 15% to produce a false twist yarn having a crimp elongation rate of 22%. The false twisted yarn and the polyester / cupra composite yarn (single yarn) used in Example 1 were simultaneously aligned and supplied to a 24-gauge single circular knitting machine, and knitting was performed while increasing the tension of the false twisted yarn so that the polyester yarn was formed on the front side. / A reversible sheet knitted fabric comprising a cupra composite yarn and a false twisted yarn on the back side was produced at the same time as in Example 1, and was similarly subjected to refining, water absorption processing, and final setting to obtain a knitted fabric III. The knitted fabric III was sewn on a shirt so that the skin side became false twisted yarn, and a monitor wearing test was performed. The results are shown in Table 1. The X value, Y value and air permeability were in the appropriate ranges. It was easy to use, the average skin temperature (standardized data) was low, and the number of wearing questionnaire scores was high.

Examples 4 to 5 and Comparative Example 2 Polyester long fibers (75d / 36f) having a specific gravity of 1.41 and containing 4.0% by weight of titanium oxide were spindle-rotated with a Mitsubishi LS-2 false twisting machine. 250,000 rpm, 320 twists
At 0 T / m, the first heater temperature was set to 200 ° C., the second heater temperature was set to 200 ° C., and the overfeed rate in the second heater zone was set to 8%, 12%, and 15% to produce three levels of false twisted yarns having different crimp elongation rates. did. or,
Polyester long fibers (75d / 36f) containing 0.1% by weight of titanium oxide and having a specific gravity of 1.38 were similarly heated at a first heater temperature of 200 ° C and a second heater temperature of 190 ° C.
° C, overfeed rate 1 in second heater zone
A false twisted yarn having a crimp elongation of 21.5% was obtained at 5%. Using these false twisted yarns, using a 28-gauge double circular knitting machine, three levels of polyester false twisted yarns having a specific gravity of 1.41 were used in a ground structure (inlaid fabric), and polyester false twisted yarns having a specific gravity of 1.38 were used as a honeycomb on the back surface. Knitting organization (Lacoste organization) 3
You got a kind of greige.

The greige of these three levels was subjected to scouring, water absorption and final setting in the same manner as in Example 1, and the X value, Y
Knitted fabrics IV, V and VII having different values and air permeability. These knitted fabrics were sewn on shirts and subjected to a monitor wearing test. The results are shown in Table 1. Since the knitted fabrics IV and V have X values, Y values and air permeability in appropriate ranges, all of them were used. The fabric was easy to shake, had low average skin temperature (standardized data), and had high wearing questionnaire scores. However, the knitted fabric VII was a hot and unpleasant knitted fabric that was hard to shake due to too high X value and Y value and had high average skin temperature.

Comparative Example 3 A cotton yarn 40 /-and a false twisted yarn similar to that in Example 3 were simultaneously aligned and supplied to a 24-gauge single circular knitting machine, and knitting was performed while increasing the tension of the false twisted yarn. Then, a reversible sheet knitted fabric having a back side made of false twisted yarn was produced at the same time as in Example 2, refined and exposed by the same method, and subjected to water absorption processing and final setting to obtain a knitted fabric VIII. The knitted fabric was sewn on a shirt so that the skin side became false twist yarn, and a monitor wearing test was performed. As shown in Table 1, the Y value of the knitted fabric was too high. ) Was expensive, hot and unpleasant knitted fabric.

[0029]

[Table 1]

[0030]

The cooling knitted fabric of the present invention can reduce the average skin temperature of the wearer due to the ventilation effect due to the vibration and swaying motion of the knitted fabric during exercise, reduce the heat, cool and wear Excellent comfort.

Claims (3)

[Claims] 1. A knitted fabric having a ground structure using long fiber yarns, wherein 25 or more long fiber yarns having a specific gravity of 1.4 or more are contained in the knitted fabric.
X value representing the fiber filling degree of the ground structure defined by the following formula (1) is 7 to 150, and Y value representing the vibration damping rate of the knitted fabric defined by the following formula (2) Is 3 or less, and the air permeability of the knitted fabric is 80 to 250 cc / cm ² · s. X = {number of courses of ground structure (pieces / inch) + number of wale (pieces / inch)} x crimp elongation rate (%) of fiber yarns constituting the ground structure ÷ 繊 維 denier fiber yarns forming the ground structure (D) (1) Y = 2HG (gf / cm) / ΔG (gf / cm · deg) (2) (2HG is shear hysteresis and G is shear rigidity) 2. The cool knitted fabric according to claim 1, wherein the ground structure is constituted by long fiber yarns having a specific gravity of 1.4 or more. 3. The cool knitted fabric according to claim 1, wherein the long fiber yarn having a specific gravity of 1.4 or more is a cellulose long fiber yarn.