JP2003155648A - Three-dimensional knit fabric for seat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a three-dimensional knit fabric for seat, useful for the seat of automobile, railway car, aircraft, etc., having excellent oscillation damping property even by upholstering the fabric on a seat as it is and exhibiting excellent shape stability after sitting for a long period or after repeated sitting. SOLUTION: The three-dimensional knit fabric for seat is composed of a pair of front and back knit fabrics and a connecting monofilament yarn bonding the fabrics and has a resonance frequency of 5-12 Hz measured by a stretched oscillation damping measurement and an acceleration transmission ratio of <=0.8 at 20 Hz.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional knitted fabric for seats of automobiles, railway vehicles, airplanes and the like.

[0002]

2. Description of the Related Art A three-dimensional knitted fabric composed of two layers of front and back knitted fabric and a connecting yarn for connecting the two layers of knitted fabric has excellent cushioning property, has a good recyclability as compared with urethane, and has a good recyclability during combustion. Since it can reduce problems such as the generation of toxic gas, and has excellent vibration damping properties and occupant retention properties, it is being applied as a cushioning material for seats and the like. For example, JP 20
JP-A No. 01-87077 discloses a seat in which a three-dimensional knitted fabric having meshes on the front and back sides is stretched over a seat cushion frame and a seat back frame.

However, for example, in the stretching of an ordinary general three-dimensional knitted fabric in which the front and back knitted fabrics are meshes, the front and back knitted fabrics are stretched when a person sits down. Since it bends and shows good cushioning properties,
Since the three-dimensional knitted fabric has a large hysteresis loss to enhance the vibration damping property, deformation of the front and back stitches caused during stretching and displacement between fibers due to deformation of the mesh form are difficult to return to the original in an instant. The problem is that the flexure of the three-dimensional knit does not recover after sitting, and the repulsive feeling of the stretched three-dimensional knit gradually decreases due to repeated sitting, leaving poor traceability after sitting. was there. Furthermore, since the vibration damping of the three-dimensional knit is not optimized, the resonance frequency is not sufficiently lowered when the sheet is formed of the three-dimensional knit alone, and the acceleration transmission ratio in the high frequency range of 15 Hz or more is sufficient. There was a problem that it was not reduced.

[0004]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems, and absorbs microvibration because it is excellent in vibration damping even when used alone in a stretchable seat sheet material.
An object of the present invention is to provide a three-dimensional knitted fabric for a seat, which is excellent in form stability when repeatedly seated and has excellent ride comfort during long-time driving.

[0005]

Means for Solving the Problems As a result of extensive studies on the vibration characteristics of a seat, the present inventor has found that the object of the present invention can be achieved by setting the resonance frequency in the vibration characteristics of a three-dimensional knitted material to a specific range. Heading out, the present invention has been completed.

That is, the present invention is as follows.

1. It is composed of two layers of front and back knitted fabric and a monofilament connecting yarn that connects the two layers of knitted fabric, and has a resonance frequency of 5 to 12 Hz in a tension type vibration damping measurement, and an acceleration transmission ratio at 20 Hz of 0.8 or less. A three-dimensional knitted fabric for seats characterized by being

2. An unprocessed yarn having an elastic modulus of 40 cN / dtex or less and an elastic recovery rate at 10% elongation of 90% or more and a yarn / yarn friction coefficient of 0.2 to 0.6, and / or an initial load of 0.25 cN / tan δ at dtex is 0.02
~ 0.1 and unloaded yarn and / or initial load 0.25c
The three-dimensional knitted fabric for a seat sheet according to the above 1, wherein a textured yarn having a tan δ in N / dtex of 0.025 to 0.2 is used for at least a part of the two-sided knitted fabric.

The present invention will be described in detail below.

The three-dimensional knitted fabric of the present invention comprises two layers of front and back knitted fabrics,
It is composed of a monofilament connecting yarn that connects the two layers of knitted fabric.

The three-dimensional knitted fabric of the present invention has a resonance frequency of 5 to 12 Hz, preferably 5 to 10 Hz, and more preferably 5 to 8 Hz in the tension type vibration damping measurement. When the resonance frequency is in this range, when the seat is constructed,
It suppresses the occurrence of secondary resonance in the high frequency range, and
Since it is different from the resonance frequency of the human body, it is difficult for unnecessary vibrations to be transmitted to the human body, so that excellent riding comfort can be obtained.

The three-dimensional knitted fabric of the present invention has an acceleration transmission ratio at 20 Hz of 0.8 or less, preferably 0.7 or less, more preferably 0.5 or less. Acceleration transmission ratio is 0.8
When it is less than the above, a comfortable ride is obtained because the vibration damping property in the high frequency range is sufficient.

The three-dimensional knitted fabric of the present invention preferably has an average rigidity when stretched of 800 to 5000 N / 5 cm, more preferably 1000 to 2500 N / 5 cm. When the average rigidity during extension is within this range, the flexibility is appropriate, so the occupant's retention when sitting on the seat is excellent, and
Since it has an appropriate resonance frequency and deformability, it provides an excellent fit and flexibility and good sitting comfort.

The three-dimensional knitted fabric of the present invention is 98
The deflection under a 0 N load is preferably 40 to 110 mm, more preferably 50 to 100 mm. When the flexure is in this range, a suitable resonance frequency and deformability are provided, so that an excellent fit and flexibility and good sitting comfort can be obtained. In addition, since the hip point when sitting does not drop too much, it is possible to maintain a stable posture.

Furthermore, the three-dimensional knitted fabric of the present invention preferably has a linearity up to 980 N load of 50% or more, and more preferably 60% or more, when stretched and compressed. When the linearity is 50% or more, the vibration damping property depending on the weight of the occupant,
There is no change in occupant retention, etc., and a comfortable sitting comfort is obtained. In addition, the hysteresis loss rate in the case of loading and unloading up to 980 N during tension compression is preferably 60% or less, and more preferably 50% or less. When the hysteresis loss ratio is 60% or less, the morphological stability after sitting for a long time or repeatedly is excellent.

As described above, the three-dimensional knitted fabric of the present invention has not only the vibration damping property but also the fit feeling, the occupant retention property, and the morphological stability by setting the elongation property and the tension type compression property, which are static properties, within a specific range. It is possible to make the seat excellent in properties and the like.

In order to obtain the three-dimensional knitted fabric of the present invention, it is preferable to use an unprocessed yarn having specific physical properties and / or a processed yarn having an improved tan δ in at least a part of the front and / or back side knitted fabric.

The unprocessed yarn has an elastic modulus of 40 cN / d.
It is preferable that the unprocessed yarn has an elastic recovery rate of 90% or more at 10% elongation or less and a yarn / yarn friction coefficient of 0.2 to 0.6. By using such an unprocessed yarn, the average rigidity at the time of extension can be set to a desired range, the deflection and the hysteresis loss at the time of tension compression can be set to a predetermined range, and the vibration damping property can be improved. If the elastic modulus is too large, the average rigidity during elongation becomes too large, and if the elastic recovery rate at 10% elongation is too small, hysteresis loss during tension-type compression may increase. If the yarn / yarn friction coefficient is too small, the energy dissipation due to the yarn / yarn friction may not be sufficient and the vibration damping property may be inferior. If it is too large, hysteresis may occur when the knitted fabric structure is deformed. Since the loss tends to increase, the yarn / yarn friction coefficient is more preferably 0.3 to 0.5, and further preferably 0.35.
Is about 0.45. Examples of such unprocessed yarn include
Examples include polytrimethylene terephthalate fibers.

Further, it is preferable to use an unprocessed yarn having a tan δ of 0.02 to 0.1 at an initial load of 0.25 cN / dtex. By using such unprocessed yarn,
The acceleration transmission ratio can be reduced. Examples of such unprocessed yarn include polyethylene terephthalate fiber,
Examples include polybutylene terephthalate fibers. Among them, polybutylene terephthalate fiber having a particularly large tan δ value is preferable, but it is not particularly limited as long as the above characteristics are satisfied.

The unprocessed yarns may be used alone or in combination of two or more.

In the present invention, the textured yarn used for the front and / or back side knitted fabric has a tan δ of 0.025 to 0.
A textured yarn of 2 is preferred. The acceleration transmission ratio can be reduced by using such a processed yarn. Examples of such textured yarns include a sweet twisted yarn to a strong twisted yarn, a false twisted textured yarn (including a drawn false twisted yarn of POY), a fluid jet textured yarn,
Processed yarns having improved tan δ such as indented processed yarns and knit denitted processed yarns can be given.

The raw yarn used for the processed yarn is not particularly limited, and examples thereof include synthetic fibers such as polyester fibers, polyamide fibers, polyacrylonitrile fibers, polypropylene fibers, natural fibers such as cotton, hemp and wool, and cupra rayon. , Regenerated fibers such as viscose rayon, lyocell, and the like. From the viewpoint of durability and elastic recovery, synthetic fibers are preferable, polyester fibers are more preferable, and polytrimethylene terephthalate fibers are further preferable.

The textured yarn may be used alone or in combination of two or more kinds.

The fineness of the fibers used in the three-dimensional knitted fabric of the present invention is
The fibers constituting the front and back knitted fabrics are usually 56 to 20.
00dtex is preferably used, but course /
From the point that the number of wells can be set within a predetermined range,
500 dtex is more preferable. The number of filaments can be set arbitrarily, but in order to improve durability, the single yarn fineness is preferably 2 to 10 dtex, more preferably 3 to 8 d.
It is desirable to set the number of filaments so as to be tex.

In the present invention, the polytrimethylene terephthalate fiber which is preferably used as the unprocessed yarn or the processed yarn is a polyester fiber containing a trimethylene terephthalate unit as a main repeating unit, and the trimethylene terephthalate unit is preferably 50 mol%. Or more, more preferably 70 mol% or more, further preferably 80 mol%
As described above, the most preferable content is 90 mol% or more.
Therefore, the total amount of the other acid component and / or glycol component as the third component is preferably 50 mol% or less, more preferably 30 mol% or less, further preferably 20 mol% or less, and most preferably 10 mol% or less. Included polytrimethylene terephthalate contained.

Polytrimethylene terephthalate is synthesized by binding terephthalic acid or a functional derivative thereof and trimethylene glycol or a functional derivative thereof in the presence of a catalyst under appropriate reaction conditions. In this synthesis process, one or more appropriate third components may be added to obtain a copolyester.

As the third component to be added, aliphatic dicarboxylic acids (oxalic acid, adipic acid, etc.), alicyclic dicarboxylic acids (cyclohexanedicarboxylic acid, etc.), aromatic dicarboxylic acids (isophthalic acid, sodium sulfoisophthalic acid, etc.) ), Aliphatic glycols (ethylene glycol, 1, 2
-Propylene glycol, tetramethylene glycol, etc.), alicyclic glycols (cyclohexanedimethanol, etc.), aliphatic glycols containing aromatics (1,4-bis (β-hydroxyethoxy) benzene, etc.), polyether glycols (polyethylene glycol) , Polypropylene glycol and the like), aliphatic oxycarboxylic acid (ω-oxycaproic acid and the like), aromatic oxycarboxylic acid (p-oxybenzoic acid and the like) and the like. Further, a compound having one or three or more ester-forming functional groups (benzoic acid or the like or glycerin or the like) can also be used within a range in which the polymer is substantially linear.

Further, matting agents such as titanium dioxide, stabilizers such as phosphoric acid, ultraviolet absorbers such as hydroxybenzophenone derivatives, crystallization nucleating agents such as talc, slip agents such as aerosil, and anti-hindering agents such as hindered phenol derivatives. An oxidizing agent, a flame retardant, an antistatic agent, a pigment, a fluorescent whitening agent, an infrared absorbing agent, an antifoaming agent, etc. may be contained.

Regarding the spinning of polytrimethylene terephthalate fiber, a method in which an unstretched yarn is obtained at a winding speed of about 1500 m / min, and then the yarn is twisted at about 2 to 3.5 times, the spinning-twisting process is directly connected. Any of the above-mentioned direct rolling method (spin draw method) and high speed spinning method (spin take-up method) with a winding speed of 5000 m / min or more may be adopted.

The fibers may be in the form of long fibers or short fibers, and may be uniform or thick in the length direction, and their cross section may be round, triangular, L-shaped, T-shaped, or Y-shaped. Mold,
W type, Yachiba type, flat type (flatness of about 1.3 to 4,
W type, I type, Bou-Melan type, corrugated type, skewer dumpling type, eyebrow type,
It may be a rectangular parallelepiped type, etc.), a polygonal type such as a dogbone type, a multileaf type, a hollow type or an indeterminate type.

Further, as the form of the yarn, spun yarn such as ring spun yarn, open-end spun yarn, original yarn (including extra fine yarn), sweet twisted yarn to strong twisted yarn, false twisted yarn (stretched false twisted yarn of POY). Included), air-jet processed yarn, push-processed yarn, knit denitted yarn, and the like.

Incidentally, within a range not impairing the object of the present invention,
Usually within the range of 50 wt% or less, natural fibers, other synthetic fibers and the like, for example, natural fibers such as cotton, wool, hemp, silk, cupra, viscose, polynosic, purified cellulose, acetate, polyethylene terephthalate and polybutylene terephthalate, Polyester fibers such as polytrimethylene terephthalate, various artificial fibers such as nylon and acrylic, as well as copolymerized types of these, and composite fibers using the same or different polymers (side-by-side type, eccentric sheath core type, etc.) are mixed-spun. (Core yarn, silospan, silo fill, hollow spindle, etc.), covering (single,
Double), for example, a low shrinkage yarn having a boiling water shrinkage ratio of about 3 to 10% or a high shrinkage yarn having a boiling water shrinkage ratio of about 15 to 30%, for example, mixed twisting, twisting, false twisting (elongation difference false twisting, drawing of POY). It may be mixed by means such as two-feed air injection processing.

In the three-dimensional knitted fabric of the present invention, a single yarn fineness 56 is used as a fiber forming a connecting yarn for connecting two layers of knitted fabric.
It is preferable to use a monofilament of about 1500 dtex. In order to maintain the cushioning property with repulsion, 200 to 1000 dtex is more preferable. Examples of such fibers include monofilaments of synthetic fibers such as polyester-based fibers, polyamide-based fibers, polyacrylonitrile-based fibers, and polypropylene-based fibers. It is preferable to use polytrimethylene terephthalate fiber.

The three-dimensional knitted fabric of the present invention can be knitted by a knitting machine having two opposing needle beds. As such a knitting machine, there are a double Russell knitting machine, a double circular knitting machine, a flatbed knitting machine having a V bed, and the like. A double Russell machine is preferably used to obtain a three-dimensional knit with good dimensional stability.

The front and back knitted fabrics of the three-dimensional knitted fabric have a structure such as a back half, a back satin, and a quinz cord capable of appropriately setting the average rigidity at the time of stretching to make the surface flat and have a good texture. However, it is preferable, but design may be imparted by knitting into a knitted fabric having a plurality of openings, such as a square or hexagonal mesh knitted fabric or a marquisette knitted fabric. The front and back knitted fabrics may have different knitting structures.

The course / well number of the knitted fabric is 10/10
30/30 pieces / 2.54 cm are preferred, especially 15/1
5 to 25/25 pieces / 2.54 cm are preferable. course/
When the number of wells is in this range, the crossing portion between the threads is sufficient, the vibration damping property due to the thread / thread friction is sufficient, the loop is not clogged too much, and problems such as thread breakage during knitting occur. Since it does not occur, a practical formation is possible. The predetermined course / well number can be achieved by appropriately selecting a knitting machine gauge, an on-machine course, heat setting conditions and the like.

The density of the connecting yarns in the three-dimensional knitted fabric is such that the total cross-sectional area (N · D / 1 × 10 ⁶ · ρ) of the connecting yarns in an area of 2.54 cm square of the three-dimensional knitted fabric is 0.05 to 0.5 cm. ²
Is preferable, and more preferably 0.1 to 0.3.
cm ² . However, N is the number of connecting yarns in the area of 2.54 cm square of the three-dimensional knit (thread / 2.54 cm square),
D represents the fineness of the connecting yarn (g / 1 × 10 ⁶ cm), and ρ represents the specific gravity of the connecting yarn (g / cm ³ ). When the density of the connecting yarns is within the above range, the three-dimensional knitted fabric has appropriate rigidity and has better cushioning properties. If the density is too low, the resilience tends to decrease, and if it is too high, the density tends to be high and the weight tends to decrease.

The connecting yarn may form loop-shaped stitches in the front and back knitted fabrics or may have a structure in which the knitted fabrics on the front and back are hooked by an insertion structure, but do not impair the extensibility of the front and back knitted fabrics. Moreover, a hooked structure is preferable. However, at least 2
In order to improve the morphological stability of the three-dimensional knitted fabric, it is preferable that the connecting yarns of the book connect the knitted fabrics on the front and back sides obliquely in mutually opposite directions and connect them in a cross shape (X shape) or a truss shape.

The thickness and basis weight of the three-dimensional knit can be arbitrarily set according to the purpose of use of the three-dimensional knit, but the thickness is 3 to 30 m.
m is preferred. When the thickness is in this range, excellent cushioning properties are obtained, and the three-dimensional knitted product can be easily finished. Basis weight is preferably from 100 to 3000 g / m ^2, more preferably from 200 to 2000 g / m ^2.

As a finishing method of a three-dimensional knit, for example, greige can be finished through steps such as scouring, dyeing, heat setting, etc., but if a stock solution colored yarn is used as the front and back and / or the connecting yarn of the three-dimensional knit, the dyeing process is It can be simplified.

When the finished three-dimensional knitted fabric is stretched on the seat frame, its end may be previously treated by means such as fusion bonding, or may be formed into a desired shape by thermoforming.

The three-dimensional knitted fabric of the present invention is stretched around a seat frame and is preferably used mainly in a hammock shape. However, the lower part of the hammock-shaped three-dimensional knitted fabric is supported by a metal wire group having a coil spring at both ends and a high wire. The cushioning property may be improved by reinforcing it with a cloth or the like having elasticity and good elongation recovery.
Further, even if it is not used in the form of a hammock and is laminated as a skin material on a seat, it will exhibit good cushioning properties.

[0043]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be further described with reference to Examples, but the present invention is not limited to the Examples.

The measuring method, the evaluating method and the like are as follows.

(1) Elongation characteristics The elastic modulus of the unprocessed yarn and the processed yarn and the elastic recovery rate at 10% elongation were measured by the following methods.

An initial load of 0.009 cN / dtex was applied to the sample, and the sample was elongated at a constant rate of 20% per minute, and the elongation was 10%.
At this point, on the contrary, shrink it at the same speed,
Draw a stress-strain curve. During contraction, the stress is equal to the initial load,
Let L be the residual elongation at the time of decreasing to 0.009 cN / dtex.

The elastic modulus is calculated by a conventional method from the inclination of elongation at elongation of 2 to 5%.

The elastic recovery rate at 10% elongation is calculated by the following formula.

Elastic recovery rate at 10% elongation (%) = [(1
0-L) / 10] × 100 (2) Yarn / yarn friction coefficient Using a knitting property measuring machine Model KS-2 (manufactured by Sugihara Keiki Co., Ltd.), at 20 ° C. and 65% RH environment, a yarn speed of 50.
It is measured under the conditions of m / min and initial thread tension of 3 g.

(3) tan δ Dynamic characteristic measuring device RSA-II (USA: RHEOMETR
(Manufactured by ICS), at room temperature, sample length 26 mm, initial load 0.25 cN / dtex, additional strain 1% constant, frequency 0.16 to 16 Hz, sine wave log sweep conditions, frequency 5, 10, It is calculated by averaging tan δ at 15 Hz.

(4) The average rigidity three-dimensional knitted fabric when stretched is sampled in a length of 300 mm and a width of 50 mm, and attached to a Shimadzu Autograph DSS2000 type (manufactured by Shimadzu Corporation) so that the chuck distance is 200 mm. Elongate to break at a pull rate of 200 mm / min to obtain a load-elongation curve. From the curve obtained, 10
% The slope between two points at elongation and at break is calculated, and the inclinations in the vertical and horizontal directions are averaged to obtain the average rigidity at elongation.

(5) Stretching type compression characteristics The inside diameter is 30c on one side with feet 15 cm in height attached to the four corners.
m, quadrangular plate-shaped metal frame having an outer diameter of 41 cm on one side (sticking sandpaper No. 40 on the top surface to provide anti-slip properties), and a quadrangle having an inner diameter of 30 cm on one side and an outer diameter of 41 cm on one side. The three-dimensional knitted fabric is sandwiched between it and the plate-shaped metal frame of (No. 40 sandpaper is attached to the lower surface to provide slip resistance), and the periphery is fixed with a vise.

A Shimadzu Autograph AG-B type (manufactured by Shimadzu Corporation) was used to compress the central portion of the stretched three-dimensional knitted fabric at a speed of 100 mm / min with a circular flat compression terminal having a diameter of 100 mm, and a load of 980 N. When it becomes, put it back at the same speed. From the load-displacement curve obtained at this time, the displacement under a load of 980 N is defined as the deflection.

An area P formed by the compression load curve and the compression displacement axis, an area R formed by the recovery compression load curve and the compression displacement axis, a line segment connecting the origin and the load at the time of deflection and the compression displacement axis. The area Q of the triangle is calculated, and the linearity L and the hysteresis loss H are calculated by the following equations.

L (%) = [P / Q] × 100 H (%) = [(P−R) / P] × 100 (6) Stretching type vibration damping characteristic Stretched in the same manner as (5) above. VIBRATION GENERATOR F-300
It is fixed to BM / A (manufactured by Emic Corporation) with bolts.
A 2 kg weight made of iron having a cylindrical shape with a diameter of 100 mm is allowed to stand so as to be horizontal to the center of the sample. An accelerometer (Made by B & K, 4371 type) that measures input acceleration on the metal frame and output acceleration at the center of the upper part of the weight is fixed with a magnet,
F via an amplifier (B & K Germany, 2692AOSI)
Connect to FT analyzer (DS2000 type, Ono Sokki Co., Ltd.).

Frequency 1-20H with constant displacement of ± 1 mm
Under the conditions of z and sine wave log sweep, acceleration is measured to obtain an acceleration transmission ratio (= output acceleration / input acceleration) -frequency curve. In the curve, the frequency at which the acceleration transmission ratio is maximized is the resonance frequency, and the acceleration transmission ratio at 20 Hz is also obtained.

(7) Vibration damping properties of the seat The chair is sewn and stretched around the frame of the chair (4 legs, no backrest) made of a 40 cm square metal frame so as not to loosen it. Then, the chair frame is bolted to the vibrator used in (6) above. Accelerometer that measures the input acceleration on the chair frame and the output acceleration on the ischium of a man weighing 65 kg (B & K 43, Germany)
71 type fixed, amplifier (German B & K, 2692A)
FFT analyzer (Ono Sokki Co., Ltd.)
DS2000 type).

Frequency of 1 to 15H with constant displacement of ± 1 mm
Under the conditions of z and sine wave log sweep, acceleration is measured and an acceleration transfer ratio-frequency curve is obtained. The acceleration transmission ratio at the resonance frequency of 10 Hz is obtained from the curve.

(8) Morphological stability After a male weighing 65 kg sat 10 times in the chair used in the evaluation of (7) for 5 minutes each, the appearance of the sagging state of the three-dimensional knitted fabric stretched on the chair was evaluated by appearance. The following four grades were evaluated.

[0060] ◎: No sag ○: Almost no fatigue △: Slightly flat X: Severe setback.

[Production Example] The polytrimethylene terephthalate monofilament used for the connecting yarn in Examples and Comparative Examples was produced by the following method.

Η _{sp / c} = 0.92 (measured at 35 ° C. with o-chlorophenol as a solvent), polytrimethylene terephthalate was discharged from the spinneret at a spinning temperature of 265 ° C., and 40
While being drawn and cooled in a cooling bath at 0 ° C., it was pulled and thinned by a first roll group at a speed of 16.0 m / min to obtain an unstretched monofilament yarn.

Then, the film was stretched 4.9 times in a drawing bath at a temperature of 55 ° C. and pulled by a second roll group of 78.4 m / min, and then subjected to relaxation heat treatment in a steam bath at 120 ° C. After passing through the third roll group of 0.6 m / min, it is wound by a winder having the same speed as the third roll group, 280 d.
A drawn monofilament of tex was obtained.

[Example 1] Using a 18-gauge, 12-mm double-rassel knitting machine equipped with 6 reeds, four reeds (L1, L2, L5, L6) forming front and back knitted fabrics were used to form 167 dtex. Polytrimethylene terephthalate monofilament obtained from the production example from two reeds (L3, L4) forming the connecting yarn all-in with the unprocessed yarn of the / 48 filament polytrimethylene terephthalate fiber (manufactured by Asahi Kasei) Three-dimensional knitted fabric with front-back back half structure in which the connecting yarn partially supplies a cross structure (x structure) in the knitting structure shown below, which is supplied to the guide in a 1-in-1-out arrangement and is 15 courses / 2.54 cm. Was organized.

This three-dimensional knitted fabric was pre-set at 170 ° C. for 45 seconds free, scoured at 70 ° C. for 20 minutes, dried, and then heat set (170 ° C. × 45 seconds) to obtain a three-dimensional knitted fabric. The results of evaluating the properties of the obtained three-dimensional knitted fabric are shown in Table 1.

(Knitting structure) L1: 1011/2322 L2: 1211/1011 L3: 1023/4532 L4: 4532/1023 L5: 1112/1110 L6: 1110/2223 The obtained three-dimensional knitted fabric has excellent vibration damping properties. Also, the evaluation of the monitor was good. Further, it had an excellent characteristic that it had an excellent feeling of repulsion even when it was repeatedly seated and that there was almost no change in its shape.

[Examples 2 and 3] In Example 1, the fibers used for the front and back knitted fabrics were 167 dtex / 48 filament polyethylene terephthalate fiber (manufactured by Asahi Kasei Corp.) unprocessed yarn (Example 2), 167 dtex / 48. A three-dimensional knitted fabric was obtained in the same manner as in Example 1 except that the filament was changed to a 2-heater processed yarn (Example 3) of polytrimethylene terephthalate fiber (manufactured by Asahi Kasei Corp.). The results of evaluating the properties of the obtained three-dimensional knitted fabric are shown in Table 1.

The obtained three-dimensional knitted fabric had excellent vibration damping properties, and the monitor evaluated it well. Further, it had an excellent characteristic that it had an excellent feeling of repulsion even when it was repeatedly seated and that there was almost no change in its shape.

[Examples 4 to 6] In Examples 1 to 3,
A three-dimensional knitted fabric was obtained in the same manner as in Examples 1 to 3 except that a three-dimensional knitted fabric having front and back quinz cord structures in which the connecting yarn partially forms a cross structure (x structure) was knitted with the following knitting fabric. The results of evaluating the properties of the obtained three-dimensional knit are shown in Table 1.
Shown in.

(Knitting structure) L1: 1011/3433 L2: 0111/1000 L3: 1023/4532 L4: 4532/1023 L5: 0001/1110 L6: 1110/3334 The obtained three-dimensional knitted fabric has excellent vibration damping properties. Also, the evaluation of the monitor was good. Further, it had an excellent characteristic that even if it was repeatedly seated, it had an excellent feeling of repulsion and almost no change in morphology was observed.

Example 7 In Example 4, the knitted solid knitted fabric was pre-set at 170 ° C. for 45 seconds and the length / course / well number was 15/15 / 2.54 cm, and 70 ° C. × After scouring and drying for 20 minutes, heat setting (170 ° C. × 45 seconds) was performed so that the number of courses / well was 15/15 / 2.54 cm in a fixed length to obtain a three-dimensional knitted fabric. The results of evaluating the properties of the obtained three-dimensional knitted fabric are shown in Table 1.

The obtained three-dimensional knitted fabric was extremely excellent in vibration damping property, but was slightly inferior in morphological stability upon repeated seating.

Example 8 In Example 4, the knitted solid knitted fabric was scoured at 70 ° C. for 20 minutes, dried, and then heat-set (185 ° C. × 50 seconds) free to obtain a solid knitted fabric. The results of evaluating the properties of the obtained three-dimensional knitted fabric are shown in Table 1.

Although the obtained three-dimensional knitted fabric was slightly inferior in vibration damping property, it had excellent repulsion feeling even after repeated seating, and had excellent properties with almost no change in morphology.

Comparative Example 1 An unprocessed yarn of 167 dtex / 48 filament polyethylene terephthalate fiber (manufactured by Asahi Kasei Co., Ltd.) used for the front and back knitted fabrics in Example 2 was stretched to a stretch ratio of 1
Continuous heat treatment was performed at 0% with 180 ° C dry heat. The obtained fiber had a tan δ reduced to 0.015. A three-dimensional knit fabric was obtained in the same manner as in Example 2 except that the fibers were used for the front and back knitted fabrics. The results of evaluating the properties of the obtained three-dimensional knitted fabric are shown in Table 1.

As is clear from Table 1, since the acceleration transmission ratio at high frequencies is large and the vibration is not sufficiently damped,
It was inferior in vibration damping.

Comparative Example 2 9 gauge equipped with 6 reeds,
From the four reeds (L1, L2, L5, L6) that form the front and back knitted fabrics using a double Russell knitting machine with a 14mm shuttle
670 dtex / 108 filament polyethylene terephthalate fiber (manufactured by Asahi Kasei Corp.) unprocessed yarn 1 in 1
Out of two reeds (L3, L4) forming a connecting yarn, 880 dtex of polyethylene terephthalate monofilament (Asahi Kasei Co., Ltd.) is supplied to the guide in a 1-in-1 out arrangement and driven 10 courses / 2.54 cm
Then, a three-dimensional knit having a front and back mesh design in which the connecting yarn partially forms a cross structure (x structure) in the knitting structure shown below was knitted.

This three-dimensional knitted fabric was preset at 170 ° C. for 45 seconds at a constant length, scoured at 70 ° C. for 20 minutes, dried, and then heat set (170 ° C. for 45 seconds) to obtain a three-dimensional knitted fabric. The results of evaluating the properties of the obtained three-dimensional knitted fabric are shown in Table 1.

(Knitting structure) L1: 1011/2322 L2: 2322/1011 L3: 1023/4532 L4: 4532/1023 L5: 2223/1110 L6: 1110/2223 As is clear from Table 1, the resonance frequency is large, It is inferior in comfort because it easily resonates with the human body.

[Comparative Example 3] Example 1 is the same as Example 1 except that the driving is changed to 32 courses / 2.54 cm.
The knitting was attempted in the same manner as, but fluffing and yarn breakage occurred due to the fibers coming into contact with each other, and practical knitting was not possible.

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[Table 1]

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INDUSTRIAL APPLICABILITY The three-dimensional knitted fabric of the present invention is excellent in the vibration damping property even if it is a sheet composed of the stretched three-dimensional knitted fabric alone.
It is possible to improve morphological stability after sitting for a long time or repeatedly.

Claims (2)

[Claims] 1. A front and back knitted fabric and a monofilament connecting yarn for connecting the two knitted fabrics, wherein a resonance frequency in a tension type vibration damping measurement is 5 to 12 Hz, and an acceleration transmission ratio at 20 Hz. Is 0.8 or less, a three-dimensional knitted fabric for seats. 2. The elastic modulus is 40 cN / dtex or less and 1
An unprocessed yarn having an elastic recovery rate of 90% or more at 0% elongation and a yarn / yarn friction coefficient of 0.2 to 0.6, and / or a tan δ at an initial load of 0.25 cN / dtex of 0.02. ~
Unprocessed yarn with 0.1 and / or initial load of 0.25 cN
The three-dimensional knitted fabric for a seat sheet according to claim 1, wherein a textured yarn having a tan δ at / dtex of 0.025 to 0.2 is used for at least a part of the front and back two-layer knitted fabric.