JP3284805B2 - Textile for industrial materials - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a woven fabric for use in industrial materials. More specifically, the present invention relates to a woven fabric for industrial materials, which is a flexible fabric, has excellent mechanical strength and other isotropic properties, and is capable of producing high-quality industrial material products with good workability such as cutting and sewing.

[0002]

2. Description of the Related Art Textiles for industrial materials are used for seat belts, airbags, canvases, architectural / civil engineering nets, luggage, and the like.

[0003] The general required characteristics of textiles for industrial materials include mechanical strength and surface characteristics such as friction and slip, heat resistance, dimensional stability and the like according to the application. In addition, airbag fabrics and the like are required to be lighter and more flexible, and for this reason, it has been proposed to manufacture textiles for industrial materials using filament yarns with reduced total fineness or single yarn fineness. Have been.

On the other hand, the mechanical properties such as tensile strength and tear strength of the woven fabric, and the physical properties such as the flexibility of the fabric, have substantially the same properties in the warp and weft directions of the woven fabric. It is desired from the viewpoint of ease of design at the time of cutting and cutting, and quality assurance.

In view of the isotropy of the airbag fabric, Japanese Patent Laid-Open Publication No. 3-137245 discloses that the warp and the weft are made identical by using the same yarn for both the warp and the weft, thereby making the warp essential. It has been described that the obtained fabric has mechanical properties and is substantially equal in the weft direction. However, the fineness of single filaments of the filaments constituting this woven fabric was as thick as 4.3d or more, so that it was inferior in terms of flexibility and the like.

Japanese Patent Application Laid-Open No. Hei 4-2835 discloses an example of weaving of an airbag fabric in which the same yarn is used for the original yarns of the warp and the weft and the number of driving is made equal. Conditions are indicated. However, this embodiment does not impart isotropy to the airbag base fabric, and does not describe the warp and weft characteristics of the obtained base fabric at all.

[0007]

However, in general, in textiles for industrial materials, the smaller the fineness of a single yarn constituting the textile, the more likely the characteristics of the finally woven textile to differ from the warp direction to the weft direction.

That is, even if a multifilament yarn having the same strength is used for the warp and the weft, and the woven fabric is woven with the same number of threads in both the warp direction and the weft direction, the weaving machine used, the weaving method, and the applied tension during weaving can be used. The mechanical properties of the fabric differ between the warp direction and the weft direction depending on the level and the like. In recent years, due to advances in looms, weaving is often performed at high speed and high density using a water jet loom or air jet loom, but in these cases, the strength of warp and weft is reduced in the fabric manufacturing process. Difference is easy to come out. In particular, in the case of weaving using a fine single-filament yarn having a single-fiber fineness of 4.0 d or less, the difference in strength tends to be further increased. As a result, not only strength characteristics but also other properties such as flexibility are obtained. In terms of characteristics, the fabric is anisotropic in the warp and weft directions.

As described above, it is difficult to impart isotropy to a filament yarn woven fabric having a fineness of single yarn of 4.0 d or less by the conventional method.

In order to make the strength in the warp direction and the weft direction of the woven fabric isotropic, a method of adjusting the number of driving of the warp, that is, increasing or decreasing the number of driving of either the warp or the weft, Alternatively, a method of adjusting the yarn quality such as the yarn fineness of the warp and the weft can be considered. However, according to this method, since the density of the single yarns is different between the warp direction and the weft direction, other characteristics such as flexibility are different between the warp direction and the weft direction. Therefore, even if the strength is isotropic in the process, it is still difficult to obtain a woven fabric that can treat the warp and weft directions equally during cutting and sewing.

Therefore, the present invention solves the above-mentioned problems in the prior art, and even if the woven fabric for industrial materials is composed of filament yarn having a small single-filament fineness, the woven fabric for mechanical strength such as tensile strength and tearing strength is obtained. Providing textiles for industrial materials that can be easily designed so that both physical properties such as characteristics and flexibility are almost the same in the warp and weft directions, the warp and weft directions are equalized during cutting and sewing The main purpose is to provide a fabric that can be handled.

[0012]

Means for Solving the Problems In order to achieve the above-mentioned object, the woven fabric for industrial materials of the present invention is characterized in that both the warp of the decomposed yarn of the woven fabric and the weft of the decomposed yarn of the woven fabric have a single-filament fineness. Is 4.0d
A woven fabric comprising the following multifilament yarns, wherein the warp strength of the decomposed yarn of the woven fabric and the decomposition of the woven fabric
Strength of the yarn of the weft is at both 6.5 g / d or more, and the difference between the intensity of the component yarns of weft strength and fabric component yarns of the warp of the fabric (absolute value) or less 0.5 g / d Yes, woven
Has a cover factor of 1700 or more .

Furthermore, the industrial materials for fabric, the warp and weft yarns are made of the same filament yarn, weaving the difference between the warp direction and the weft direction of the density is not more than two per inch <br/> Is preferred.

[0014] In addition, the filaments that constitute it, 8
It is preferable that 5% by weight or more of the polyester filaments are composed of ethylene terephthalate units, and the total fineness of the multifilament yarns forming the warp and the weft is 10%.
It is preferably from 0 to 700d.

Furthermore, it is preferable that the woven structure is a plain woven fabric, the cover factor is 1700 or more, and the flexibility of the woven fabric by the cantilever method is 150 mm or less in both the warp and weft directions, and the difference is 20 mm or less.

This woven fabric is particularly useful as a base fabric for an airbag.

The single-filament fineness of the multifilament yarn constituting the textile for industrial materials of the present invention is 4.0 d or less, preferably 0.1 to 0.1%, as the single-filament fineness of the decomposed yarn obtained by decomposing the woven fabric.
It is 4.0d, more preferably 0.2 to 2.0d.
In order to set the single yarn fineness of the decomposed yarn within the above range, usually,
The single yarn fineness in the yarn stage may be designed to be equal or slightly smaller.

When the single yarn fineness of the decomposed yarn is more than 4.0 d, the flexibility of the woven fabric is inferior and it is difficult to obtain a high quality woven fabric. . However, if the thickness is too small, such as less than 0.1 d, it is difficult to form a yarn by the direct spinning method, and there is a problem in practicality in industrial practice, which is not preferable.

Further, the multifilament yarn constituting the woven fabric for industrial materials must have a decomposed yarn strength of 6.5 g / d or more for both warp and weft, and more preferably 7.0 g / d or more. is there. When either or both of the warp and the weft are less than 6.5 g / d, in order to increase the mechanical strength of the fabric itself to a level corresponding to the application,
It is necessary to increase the number of drivings more than necessary or to increase the total fineness of the filament yarn more than necessary, and conversely, it impairs flexibility and lightness, and impairs weaving. Problems arise and are inappropriate.

In the present invention, it is important that the difference in the strength of the decomposed yarn between the warp and the weft is 0.5 g / d or less. If the difference exceeds 0.5 g / d, it is necessary to design the fabric so that various physical properties such as tensile strength, tear strength and flexibility are almost equal in the warp and weft directions. It is difficult to achieve the intended purpose of the present invention.

In particular, in the case of the present invention, the woven fabric is designed so that the number of wefts is substantially equal to each other such that the difference between the weaving density in the warp direction and the weft direction is 2 or less per inch.
An isotropic woven fabric having almost the same physical properties in the warp and weft directions can be easily designed.

The filament yarn constituting the textile for industrial materials in the present invention is not particularly limited as long as it has the above-mentioned properties.
Known filament yarns can be used. For example, polyethylene terephthalate, polyester such as polybutylene terephthalate, polyarylate, polyhexamethylene adipamide, polytetramethylene adipamide,
It is possible to use a filament yarn made of polyamide such as polycapramid, or polyolefin such as polyethylene or polypropylene. From the viewpoint of high-strength fibers, filament yarns made of polyvinyl alcohol or aromatic polyamide having a high degree of polymerization obtained by wet spinning, dry spinning, or dry-wet spinning can also be used.

Among them, filament yarns that can be melt-spun and have excellent mechanical properties and heat resistance, for example, filament yarns made of polyester or polyamide are preferable in consideration of ease of production and functions. In particular, a polyethylene terephthalate-based polyester filament yarn comprising 85% by weight or more of ethylene terephthalate units is most preferable from the viewpoint of dimensional stability.

The polymer used may contain other copolymer components and additives for the purpose of enhancing the spinnability as long as the inherent excellent properties are not impaired. In addition, as long as the spinnability is not impaired, a flame retardant or an antioxidant may be added for the purpose of enhancing the performance of the fabric.

The total fineness of the filament yarn is 100 to 700d, preferably 200 to 500d, for the decomposed yarn.

When the total fineness of the decomposed yarn exceeds 700 d, the thickness of the woven fabric becomes too thick, and the flexibility and lightness are easily impaired, and the compactness is also poor. Conversely, the total fineness is 1
If it is less than 00d, it is difficult to increase the mechanical strength of the woven fabric to a level required for industrial materials, no matter how densely woven it is at the current strength level.

The woven fabric for industrial materials of the present invention can have a woven structure depending on the application, but plain weave is preferred from the viewpoint of ease of weaving. In addition, the weaving density can be widely used depending on the purpose, from an open type to a high-density low-breathable woven fabric. However, in the case of a high-density woven fabric, the effect of the present invention can be more significantly exerted.

Specifically, in the case of plain weave, the cover factor is preferably 1700 or more, more preferably 19
00 or more .

Furthermore, the fabric for industrial materials according to the present invention has a flexibility of 150 as measured by the cantilever method.
Excellent flexibility of not more than mm can be obtained, and the difference in flexibility between the warp direction and the weft direction is not more than 20 mm, so that excellent flexibility can be obtained.

As described above, when the single yarn fineness of the filament yarn constituting the woven fabric for industrial materials is small, attention is paid to the strength characteristics of the warp and the weft in the woven fabric, and the strength characteristics satisfy a specific value. By weaving under such conditions, it is possible to easily design a woven fabric having excellent isotropy in the process. Further, the anisotropy of the characteristics in the warp direction and the weft direction generated at the time of weaving can be correctly grasped, and it becomes easy to design an appropriate woven fabric in consideration of lightness and flexibility.

In particular, when the same filament yarn is used for the warp and the weft, and the number of woven fabrics is substantially the same in the warp direction and the weft direction, an isotropic woven fabric having high strength and excellent flexibility is used. Can be easily obtained.

The woven fabric for industrial materials of the present invention can be easily produced by the following method.

The filament yarn constituting the woven fabric may be produced by a usual spinning method. 6.5 g in the strength of cracked yarn
In order to obtain a high-strength yarn of at least / d, it is preferable that the yarn has a strength of usually 8.0 g / d at the stage of the original yarn. In order to obtain fibers having such a strength, it is generally desirable to use a polymer having a high degree of polymerization. In the case of polyethylene terephthalate, a polymer having an intrinsic viscosity of 1.0 or more, and in the case of polyhexamethylene adipamide, Has 9
What is necessary is to use the thing of 2.7% or more in 8% sulfuric acid relative viscosity.
If the viscosity is lower than this, it may be difficult to obtain sufficient high elongation characteristics even if the spinning conditions are optimized and improved. However, if the viscosity is too high, industrial spinning becomes difficult. Therefore, it is preferable to set the intrinsic viscosity to 1.7 or less and 98% sulfuric acid relative viscosity to 5.0 or less at most.

The spinning temperature varies depending on the type of the polymer used. In the case of polyethylene terephthalate or polyhexamethylene adipamide, the spinning temperature is usually in the range of 280 ° C. to 310 ° C.

In the case of the above-mentioned polymers such as polyethylene terephthalate, polyhexamethylene adipamide, and polycaprolactam, generally, 10 to 10
It is preferable to use a heating cylinder having a length of 100 cm and controlled at a temperature of 200 to 350 ° C. to delay the solidification of the molten polymer to develop high strength. The length and temperature conditions of the heating cylinder may be optimized depending on the fineness of the obtained yarn and the number of filaments.

The spun yarn is once wound up or continuously stretched to give a desired high strength. The stretching conditions may be determined as appropriate depending on the type of polymer used, the degree of polymerization thereof, and the physical properties of the undrawn yarn stage. Usually, it may be performed by a conventional thermal stretching, and multi-stage stretching of two or more stages is preferable.

Subsequently, the drawn yarn is heat-set. The heat fixing may be performed by a usual method such as bringing the yarn into contact with a heat roller or a hot plate, or passing the yarn through a high-temperature gas. At this time, it is possible to control the dry heat shrinkage by changing the tension and the temperature during the heat setting.

In the present invention, the filaments constituting the textile for industrial materials are preferably subjected to an entanglement treatment in the stretching step and the heat setting step in order to further suppress the generation of fluff. For the entanglement, a normal method such as air entanglement can be employed. For example, in the case of air entanglement, the desired degree of entanglement can be achieved by appropriately changing the pressure of the supply air in accordance with the fineness and tension of the yarn used. In this case, the confounding degree is preferably 30 or more, and more preferably 50 or more.

The filament yarn obtained by drawing and heat setting usually has a total fineness of 80 to 700 d and a single fineness of 4.
It is preferable to have a characteristic of 0 d or less and a tensile strength of 8.0 g / d or more.

In order to prepare a woven fabric for industrial materials using the multifilament yarn, the obtained filament yarn may be used as it is for a warp and a weft, and weaving may be performed by a usual method under the appropriate tension conditions. The loom is not particularly limited, and weaving methods such as a rapier, a water jet loom, and an air jet loom can be used. At this time, processing such as twisting and gluing is not required, but may be performed as necessary. The weave structure is not particularly limited, such as plain weave and oblique weave, but plain weave is preferable from the viewpoint of easy production.

In order to make the strength of the decomposed yarn of the woven fabric 6.5 g / d or more, usually, as described above, the original yarn strength is 8.0 g / d.
What is necessary is just to weave using the above-mentioned filaments and not to damage the filaments. That is, excessive bending of the filament yarn during weaving causes a significant decrease in strength, and it is easy to obtain a high-strength woven fabric.

Further, in order to make the strength difference of the decomposed yarn between the warp direction and the weft direction 0.5 g / d or less, the warp direction, the weft direction, the weft direction What is necessary is just to control the tension at the time of weaving in the direction.

The tension can be controlled by, for example, applying a load to the warp to be fed to apply tension, or slightly relaxing the tension of the weft that had been applied immediately before the reed is driven. Good. In short,
What is necessary is just to make the tension level of a warp higher than before and / or to make the tension level of a weft lower than before, and those tensions are 0.5 g of difference in strength between the warp and the weft in the obtained woven fabric.
/ D or less. In particular,
When the same filament yarn is used for the warp and the weft and woven by using the same number of yarns, the tension level may be controlled so that the crimp between the warp and the weft in the woven fabric is substantially the same.

When a filament yarn having a large single yarn fineness is used, a difference in strength between the warp and the weft hardly occurs at the time of weaving even with the conventional method in which the tension is not controlled at the time of weaving. For thin filament yarns,
As described above, a difference in strength between the warp and the weft occurs during weaving. Although the cause of this difference in strength has not been clearly elucidated, the finer the fineness, the more the flexibility of the filament increases and it is more susceptible to contact with guides. This is presumed to be caused by the fact that defects tend to occur, and similarly, when a contact with a guide or the like occurs, a defect is likely to become apparent. Furthermore, a polymer having a high initial modulus, such as polyethylene terephthalate, tends to be more susceptible to the influence.

If the tension level during weaving is appropriately controlled as described above, the difference in mechanical properties between the warp and the weft during weaving can be achieved even when a fine yarn having a fineness of 4.0 d or less is used. Generation can be sufficiently suppressed,
The strength level of the decomposed yarn of the obtained woven fabric can be made substantially the same (strength difference of 0.5 g / d or less).

According to the above-described weaving method, further, the same filament yarn is used for the warp and the weft, and the condition is that the number of driving is substantially the same so that the difference in weaving density of the warp is 2 or less per inch. When weaving with
The isotropy of the process is extremely excellent. For example, in the case of the plain woven fabric obtained by the above method, the flexibility in both the warp direction and the weft direction of the woven fabric by the cantilever method is 150 m.
m, and the difference between the warp direction and the weft direction of the flexibility can be extremely reduced to 20 mm or less.

The thus obtained woven fabric for industrial materials of the present invention may be subjected to scouring, heat setting, and calendering on one or both sides by a known method, if necessary, as long as the properties of the present invention are not impaired. It does not hurt to give anything.

In particular, when the fabric is used as a base fabric for an air bag, it is preferable that the fabric is contracted by heat setting or calendering to such an extent that the fabric is not hardened, thereby further suppressing air permeability.

Further, even when another filament is mixed as a ripstop into a part of the woven fabric, the effect of the present invention can be exhibited as long as substantially all of the filament yarns satisfy the requirements of the present invention.

[0050]

The present invention will be described below in detail with reference to examples. Each physical property in the present invention is a value measured as follows.

(1) Intrinsic viscosity (IV) of polyethylene terephthalate: Using an Ostwald viscometer, the relative viscosity ηrp of a solution in which 3.0 g of a sample was dissolved in 100 ml of orthochlorophenol was measured at 25 ° C. To calculate IV.

IV = 0.0242ηrp + 0.2634 where ηrp = (t × d) / (t0 × d0),
Here, t: fall time of solution (second), t0: fall time of orthochlorophenol (second), d: density of solution (g / cc), and d0: density of orthochlorophenol (g / cc). .

(2) Relative Viscosity of Sulfuric Acid of Polyamide: A sample is dissolved in 98% sulfuric acid at a concentration of 1% by weight, and measured at 25 ° C. using an Ostwald viscometer.

(3) Tensile strength and elongation at break of filament yarn: Measured according to JIS-L-1017.

(4) Cover factor K of fabric: Defined by the following equation.

[0056] ^{_{K = N W × D W 0.5}} + N F × D F 0.5 However, N _W: warp density (lines / inch), D _W: fabric during production of the warp fineness (denier), N _F: weft density (the / Inch), _DF : Weft fineness (denier) at the time of fabric production.

(5) Fabric flexibility: JIS-L-10
It is indicated by the bristles measured by 96 (45 ° cantilever method).

(6) Tensile strength of woven fabric: JIS-K-
The measurement is performed with a sample width of 3 cm according to 6328 (strip method). The results are shown as the average of the values in the warp and weft directions of the fabric.

(7) Tear strength of woven fabric: JIS-L-
It is measured in accordance with 1096 (trapezoid method). The results are shown as the average of the values in the warp and weft directions of the fabric.

(8) Fineness and strength of the decomposed yarn of the woven fabric: The yarn is taken out from the woven fabric, cut into a length of 25 cm under a load of about 1/3 of the fineness of the original yarn stage, and the weight is measured.
The value was converted to 9000 m, which was taken as the degraded yarn fineness. Next, a tensile test was performed at a test length of 15 cm and a tensile speed of 30 mm / min using RTM-100 manufactured by Orientec Co., Ltd., and the strength at the maximum strength point was read on the chart. The value obtained by dividing the value by the fineness of the decomposed yarn was defined as the decomposed yarn strength, and the average was calculated from five measurements.

[Examples and Comparative Examples] From polyethylene terephthalate (PET) or polyhexamethylene adipamide (N66), a filament yarn having the yarn characteristics shown in Table 1 was obtained by a usual melt spinning, drawing and heat fixing method. Manufactured. Using the obtained filament yarn, a woven fabric was produced by an air jet loom under the weaving conditions shown in Table 1. At the time of this weaving, in Examples 1-4 and Comparative Examples 1-2,
In order to make the strength levels of the warp and the weft in the woven fabric almost the same, a means for relaxing the tension of the weft at the moment of driving the reed was applied.

In the case of Example 4 and Comparative Example 5, P
The yarn was formed as a sea-island composite fiber having ET as an island component, and was subjected to desealing treatment after weaving. The yarn characteristics were indicated by values after desealing, excluding the strength and elongation values.

The fineness, strength and fabric characteristics of the decomposed yarn of the obtained woven fabric were measured, and the results are as shown in Table 1.

[0064]

[Table 1]

In Examples 1 to 4, the strength of the raw yarn is high, and the strength of the decomposed yarn of the woven fabric also shows a high value of 6.5 g / d or more. Furthermore, since the weft tension is controlled to be low during weaving, despite the use of a fineness filament yarn having a single yarn fineness of 4d or less, the warp and weft directions of the decomposition yarn strength of the obtained woven fabric are obtained. The difference is extremely small at 0.0 to 0.2 g / d. As a result, a woven fabric having excellent tensile strength, tear strength, flexibility, and balance in both weft and weft was obtained.

On the other hand, in Comparative Example 1, the raw yarn strength was low, so that the mechanical properties of the woven fabric were low and it was unsuitable as an industrial woven fabric. In Comparative Example 2, since the single yarn fineness of the filament used was too large, the woven fabric was thick and inferior in flexibility. Furthermore, in Comparative Examples 3 to 5, since the tension control during weaving was not performed, the difference between the warp direction and the weft direction of the decomposed yarn strength of the woven fabric was large, and a highly anisotropic woven fabric was obtained.

[0067]

The textile for industrial materials according to the present invention is composed of filament yarns of a specific fine single-filament fineness, and the warp and weft both have the same high strength in the woven fabric. Excellent tensile strength, tear strength, flexibility, etc. Furthermore, since it can be easily designed to have the same excellent strength and flexibility in the meridional direction and the weft direction,
It is excellent in isotropy so that it can treat the warp direction and the weft direction equally during cutting and sewing, and it can be a high-quality industrial material fabric, and it can produce high-quality industrial material products with good workability such as cutting and sewing .

For example, in the case of a base fabric for an airbag, cutting can be performed without discrimination in the weaving direction, the cutting efficiency of the base fabric can be increased, and design and processing at the time of cutting and sewing can be facilitated. It is possible to manufacture an airbag with uniform deployment and further improved safety during inflation.

Specifically, a seat belt, an airbag,
Suitable for various industrial materials such as canvas, nets for construction and civil engineering, luggage, etc., especially as a base fabric for airbags that require high density and flexibility for the purpose of isotropic and low air permeability. It is suitable for.

────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-6-306728 (JP, A) JP-A-5-321132 (JP, A) JP-A-5-214632 (JP, A) JP-A-1- 41438 (JP, A) JP-A-4-2835 (JP, A) JP-A-3-137245 (JP, A) JP-A-4-201646 (JP, A) JP-A-6-184856 (JP, A) JP-A-6-306729 (JP, A) JP-A-6-306730 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) D03D 1/00-27/18

Claims (7)

(57) [Claims] 1. A woven fabric comprising a multifilament yarn having a single-fiber fineness of 4.0 d or less, both of a warp of a decomposition yarn of the woven fabric and a weft of a decomposition yarn of the woven fabric. strength and the strength of component yarns of the weft of the fabric yarns <br/> warp is at both 6.5 g / d or more, and the strength of component yarns of weft strength and fabric component yarns of the warp of the fabric (Absolute value) is 0.5 g / d or less , and the cover factor of the woven fabric is 17
A woven fabric for industrial materials, wherein the woven fabric has a size of 00 or more . 2. The warp and the weft are composed of the same filament yarn, and the difference in the weaving density between the warp direction and the weft direction is one.
2. The textile for industrial materials according to claim 1, wherein the number is 2 or less per inch. 3. The woven fabric for industrial materials according to claim 1, wherein said multifilament yarn comprises polyester filaments in which 85% by weight or more of the constituent polymer units are ethylene terephthalate units. 4. The multifilament yarn having a total fineness of 10
The woven fabric for industrial materials according to claim 1, wherein the woven fabric has a thickness of 0 to 700d. 5. The industrial materials for textiles according to claim 1, wherein the fabric is a plain weave fabric. 6. A fabric having a flexibility value by a cantilever method of 150 mm or less in both a warp direction and a weft direction, and a difference (absolute value) between flexibility values in a warp direction and a weft direction being 20 mm or less. The textile for industrial materials according to claim 1, wherein 7. The woven fabric for industrial materials according to claim 1, wherein the woven fabric is a base fabric for an airbag.