JP5003632B2 - Temporary twisted yarn - Google Patents

Description

  The present invention relates to a temporary twist yarn that is excellent in stretchability and capable of obtaining a high-density fabric suitable for umbrellas and quilted base fabrics.

In recent years, polytrimethylene terephthalate has attracted attention as a polyester fiber having excellent stretchability, and has been favorably used for fabrics that require stretching. In order to further amplify the stretchability of polytrimethylene terephthalate, many proposals have been made regarding temporary twists and composite spinning (see Patent Documents 1 and 2). According to these inventions, it is possible to obtain a fabric having a flat surface feeling and excellent stretch, but the fabric tends to be bulky, and there is a problem that a thin woven or knitted fabric, in particular, a thin high density woven fabric cannot be formed. .
JP-A-11-93026 JP 2001-055634 A

  An object of the present invention is to provide a temporary twist yarn capable of supplying a thin fabric excellent in stretchability.

In order to solve the above-mentioned problem, the temporary twist yarn of the present invention has the following configuration. That is, an undrawn yarn of side-by-side type or eccentric core-sheath type in which one constituent component is mainly composed of polyethylene terephthalate and the other constituent component is mainly composed of polytrimethylene terephthalate, A temporary twisted yarn that is formed by drawing a temporary twist at a temperature lower than the glass transition point, and satisfies the following (1) and (2).
(1) Bulk height is 20cm ³ / g or more and less than 45cm ³ / g (2) Hot water shrinkage is 40% or more

The undrawn yarn referred to in the present invention refers to a yarn having a so-called natural draw ratio in which stress hardly increases even when stretched in a stress-elongation curve.

  ADVANTAGE OF THE INVENTION According to this invention, the temporary twist thread | yarn which can supply the thin high-density fabric excellent in the stretch property suitable for an umbrella and a quilting base fabric can be obtained.

  The temporary twisted yarn of the present invention is a temporary twisted yarn comprising a polyester composite fiber in which one constituent component is composed mainly of polyethylene terephthalate and the other constituent component is a side-by-side type or an eccentric core-sheath type composed mainly of polytrimethylene terephthalate. It is a yarn obtained by drawing and twisting an undrawn yarn such as a highly oriented undrawn yarn (POY) at a temperature below the glass transition point.

  In a normal temporary twist, heat setting is performed at a temperature higher than the glass transition point of the fiber. However, in the present invention, an undrawn yarn is intentionally stretched at a temperature lower than the glass transition point (twisted while twisted while being stretched). Then untwist). By applying the temporary drawing at the above temperature, it is possible to obtain a temporary twisting yarn having a low bulkiness and a large hot water shrinkage as described later.

The temporary twisted yarn of the present invention has a slightly crimped form compared to a normal temporary twisted yarn (set at a high temperature at the time of twisting), and the bulk height is 20 cm ³ / g or more and 45 cm. Less than ³ / g. If the bulk height is less than 20 cm ³ / g, it is no different from ordinary drawn yarns, the texture becomes hard, and is not generally preferred for clothing. On the other hand, when it is 45 cm ³ / g or more, a fabric thickness is produced when the fabric is formed, and it is unsuitable for a thin high density woven fabric or a high density knitted fabric developed with the temporary twist yarn of the present invention.

  The hot water shrinkage rate of the temporary twisted yarn of the present invention is 40% or more. When the hot water shrinkage is 40% or more, a heat treatment after the formation of the fabric eliminates the space between the warp and the weft on the fabric structure, and a high-density fabric can be formed. The same applies to the case of a knitted fabric, and the fiber is shrunk by heat treatment, so that a thin and clogged knitted fabric can be formed. On the other hand, the upper limit of the hot water shrinkage rate is not particularly limited, but is generally about 80%.

  The undrawn yarn used in the present invention is a polyester-based composite fiber that is a side-by-side type or an eccentric core-sheath type in which one component is composed mainly of polyethylene terephthalate and the other component is composed mainly of polytrimethylene terephthalate. . In the present invention, the main component refers to the maximum weight component in one or the other part.

  In order to obtain an appropriate kickback property and stretchability, the composite fibers have different intrinsic viscosities of the main polymers, the intrinsic viscosity [ηb] of the low-viscosity polyester, and the high-viscosity polyester ultimate The intrinsic viscosity ratio ([ηb] / [ηa]) of the viscosity [ηa] is preferably 0.3 to 0.8.

  Since two polymers having different intrinsic viscosities are bonded together in this way, stress is concentrated on the high viscosity side in the process of spinning and provisional, so that the internal strain differs between the two components. Therefore, due to the difference in elastic recovery rate after micro-stretching in the process and the heat shrinkage difference in the heat treatment process of the fabric, the high-viscosity side contracts greatly, and distortion occurs in the single fiber, resulting in the formation of a three-dimensional coiled helical crimp To do. It can be said that the diameter of the helical crimp and the number of crimps of the single filament are determined by the contraction difference (including the elastic recovery rate difference) between the high contraction component and the low contraction component. The larger the contraction difference, the larger the diameter of the helical crimp. Is small, and the number of crimps of the single filament increases. As a stretch material, the coil crimp has a small diameter of the helical crimp, a large number of crimps of the single filament (that is, excellent stretch characteristics and good appearance), and the helical crimp has good sag resistance. (The amount of helical crimp sag according to the number of expansions and contractions is small and the stretch retainability is excellent). Furthermore, since the stretch property of the helical crimp is dominated by the stretch property of the high shrinkage component with the low shrinkage component as a fulcrum, the polymer used for the high shrinkage component preferably has high extensibility and recoverability, Polyethylene terephthalate may be disposed as a low shrinkage component, and polytrimethylene terephthalate as a high shrinkage component.

  The polyethylene terephthalate used for the polyester composite fiber is composed of a polymer component having an ethylene terephthalate unit as a main repeating unit. That is, a polyester obtained using terephthalic acid as the main acid component and ethylene glycol as the main glycol component is preferable. The copolymerization component which can form another ester bond may be contained in the ratio of 20 mol% or less, Preferably it is contained in the ratio of 10 mol% or less. Examples of the copolymerizable compounds include isophthalic acid, succinic acid, cyclohexanedicarboxylic acid, adipic acid, diamic acid, sebacic acid, dicarboxylic acids such as 5-sodium sulfoisophthalic acid, triethylene glycol, polyethylene glycol, propanediol, and butanediol. Diols such as pentanediol, hydroquinone and bisphenol A can be used. If necessary, titanium dioxide as a matting agent, fine particles of silica or alumina as a lubricant, hindered phenol derivatives, coloring pigments as an antioxidant may be added.

  The polytrimethylene terephthalate used for the polyester-based composite fiber is composed of a polymer component having a trimethylene terephthalate unit as a main repeating unit. That is, a polyester obtained using terephthalic acid as the main acid component and 1,3-propanediol as the main glycol component is preferable. The copolymerization component which can form another ester bond may be contained in the ratio of 20 mol% or less, Preferably it is contained in the ratio of 10 mol% or less. As copolymerizable compounds, dicarboxylic acids such as isophthalic acid, succinic acid, cyclohexanedicarboxylic acid, adipic acid, dimer acid, sebacic acid, 5-sodium sulfoisophthalic acid, ethylene glycol, diethylene glycol, butanediol, neopentyl glycol, cyclohexane Diols such as dimethanol, polyethylene glycol and polypropylene glycol can be used. If necessary, titanium dioxide as a matting agent, fine particles of silica or alumina as a lubricant, hindered phenol derivatives, coloring pigments as an antioxidant may be added.

Polytrimethylene terephthalate has the same mechanical and chemical properties as polyethylene terephthalate and polybutylene terephthalate, which are typical polyester filaments, and is extremely excellent in stretch recovery. This is because the methylene chain of the alkylene glycol part in the polytrimethylene terephthalate crystal structure has a Gauche-Gauche structure (the molecular chain bends at 90 degrees), and is further constrained by the interaction between benzene rings (stacking, parallel). It is thought that the molecular chain is easily stretched and recovered by the rotation of the methylene group because the point density is low and the flexibility is high.
In the present invention, the intrinsic viscosity of polytrimethylene terephthalate is preferably 1.0 or more from the viewpoint of obtaining coiled crimps and obtaining desired stretchability when a knitted fabric is formed. More preferably.
The single fiber cross-sectional shape of the polyester composite fiber used in the present invention is a side-by-side type or an eccentric core-sheath type. If the cross-sectional shape is not the side-by-side type or the eccentric core-sheath type, when heat is applied to the yarn, the coiled helical crimp does not appear, and the yarn cannot be provided with stretchability.

  The weight ratio of polyethylene terephthalate / polytrimethylene terephthalate in the polyester-based composite fiber is in the range of 30/70 or more and 70/30 or less from the viewpoints of yarn production and dimensional uniformity of the coil in the fiber length direction. Preferably it is 35/65 or more and 65/35 or less, More preferably, it is the range of 40/60 or more and 60/40 or less.

  In the present invention, the temporary twist yarn may be composed only of the polyester composite fiber, but may be a mixed fiber of the polyester composite fiber and other fibers. The other fiber may be either a filament yarn or a spun yarn. Specifically, the filament yarn is preferably polyamide, polyethylene terephthalate, or other materials such as rayon, acetate, acrylic, polypropylene, polytrimethylene terephthalate, polybutylene terephthalate, polyhexamethylene terephthalate, vinyl chloride, synthetic fiber or silk. The embodiment may be any of a raw yarn, false twisted yarn, original yarn, pre-dyed yarn, or a composite yarn thereof.

  Also preferred are spun yarns made of synthetic fibers such as cotton fibers, animal hair fibers such as wool, natural fibers such as hemp and silk, rayon, polyamide, polyester, acrylonitrile, polypropylene, and vinyl chloride. Or any of the spun yarn blended may be sufficient.

  As a method of blending, any of air blending such as entanglement processing and fluid turbulent processing, combined twisting, fine spinning and twisting may be used.

  The temporary twisted yarn of the present invention can be manufactured as follows, for example.

  That is, a polyester mainly composed of polyethylene terephthalate and a polyester mainly composed of polytrimethylene terephthalate are individually melted, and then merged on the upstream side of the discharge hole of the base, and from the side-by-side type or eccentric core-sheath type discharge hole Spin. Thereafter, the polymer is cooled and solidified and wound up as an undrawn yarn.

  Next, the obtained undrawn yarn is passed through the process shown in FIG. 1 to obtain the temporary twist yarn of the present invention. In the step shown in FIG. 1, first, the unstretched yarn 1 is temporarily stretched between the feed roller 2 and the deliberry roller 4. At this time, in a normal drawing temporary twist, in order to heat-set the yarn, a heater is used between the feed roller 2 and the twister 3, and the yarn is processed at a temperature higher than the glass transition point of the yarn. However, in the process for producing the temporary twisted yarn of the present invention, in order to obtain a temporary twisted yarn having a low bulk height and a high hot water shrinkage rate, for example, by not using a heater, the temporary twisted yarn at a temperature below the glass transition point. (Twist while stretching, then untwist).

  For the twister 3, any of a pin type, a friction type, a belt nip type, and the like may be used. The yarn twisted at a temperature lower than the glass transition point is wound as a package 6 by the winder 5.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

The intrinsic viscosity [η], bulk height (cm ³ / g), and hot water shrinkage (%) in the examples were determined by the following methods.

<Intrinsic viscosity [η]>
A sample of 0.10 g was dissolved in 10 ml of orthochlorophenol and measured using an Ostwald viscometer at a temperature of 25 ° C.

<Shaft altitude (cm ³ / g)>
The measurement was performed according to the test method described in JIS-L-1013 (1999) “Testing method for chemical fiber filament yarn” “8.16 Bulkiness” a) Method A (parallel method). The number of tests was five, and the average value was defined as the bulk height.

<Hot water shrinkage (%)>
The measurement was carried out according to the test method described in JIS-L-1013 (1999) “Testing method for chemical fiber filament yarn”, “8.18.1 Hot water shrinkage rate” a) skein shrinkage rate (Method A). The number of tests was 5, and the average value was defined as the hot water shrinkage.

<NDR (%)>
A load-elongation curve is taken according to the test method described in “8.5.1 Standard time test” of “Test method for chemical fiber filament yarn” in JIS-L-1013 (1999). At this time, in the undrawn yarn, a region (I) in which the load increases in direct proportion to the amount of elongation is observed, and then a yield point (II) that rapidly decreases after the load reaches a maximum appears. When the extension is further performed, the region (III) where the load is constant continues for a while, and then the region (IV) where the load increases again is seen, and the cutting point is reached each time. Here, NDR refers to an elongation value corresponding to the boundary between the (III) region and the (IV) region, and the average value of 10 measurements is defined as NDR in the present invention.

<Elongation at break (%)>
JIS-L-1013 (1999) “Chemical Fiber Filament Yarn Test Method” “8.5.1 Standard time test” is used to determine the elongation, and this measurement is repeated 10 times. Degree.

<Elongation rate of fabric (%)>
JIS-L-1096 (1999) “8.14.1 Elongation ratio” of “General textile test method” a) The warp direction and weft of the fabric according to the test method described in Method A (constant speed extension method) The elongation rate in each direction was determined. The number of tests was 3 times in each direction, and the average value was taken as the elongation rate.

<Thickness of fabric (mm)>
The measurement was carried out according to the test method described in “8.5.1 Thickness of fabric” in “JIS-L-1096 (1999)“ General fabric test method ”. Measurement was carried out at five different locations of the sample, and the average value was obtained as the thickness of the fabric.
[Example 1]
Polytrimethylene terephthalate with an intrinsic viscosity of 1.31 and polyethylene terephthalate with an intrinsic viscosity of 0.52 were melted separately, and the weight ratio of polyethylene terephthalate / polytrimethylene terephthalate from a composite spinneret with 34 holes at a spinning temperature of 260 ° C. Was discharged at a spinning speed of 2200 m / min to obtain a highly oriented undrawn yarn of 115 dtex 34 filaments. The obtained highly oriented undrawn yarn had an NDR of 31% and a breaking elongation of 109%. The glass transition points of polytrimethylene terephthalate and polyethylene terephthalate were 51 ° C. and 69 ° C., respectively.

Thereafter, the highly oriented undrawn yarn was subjected to the process shown in FIG. 1, and the temporary twisted yarn of the present invention was processed under the following conditions.
[Temporary twist condition]
Using a pin temporary twisting machine TFT-6M manufactured by Toray Engineering Co., Ltd., a temporary twisting process was performed at room temperature (20 ° C.) under the following conditions to obtain a temporary twisting thread.

Spindle speed: 300000 rpm
Temporary twist: 3450 T / m
Draft: 1.4
Table 1 shows the bulk height and the hot water shrinkage of the obtained temporary twisted yarn.

  Using the obtained temporary twisted yarn together with the warp and the weft, a plain weave fabric was prepared. This was immersed in hot water at 100 ° C. for 20 minutes in a free state to obtain a woven fabric. Table 2 shows the density of the well and the course after the raw machine and the hot water treatment, the stretch rate and the thickness of the fabric after the hot water treatment.

[Example 2]
The undrawn yarn obtained in Example 1 was temporarily twisted at room temperature (20 ° C.) under the following conditions to obtain a temporary twist yarn.
[Temporary twist condition]
Spindle speed: 300000 rpm
Temporary twist: 3450 T / m
Draft: 1.6
Table 1 shows the bulk height and the hot water shrinkage of the obtained temporary twisted yarn.
In the same manner as in Example 1, the temporary twisted yarn obtained was used for both warp and weft to produce a plain weave fabric. This was immersed in hot water at 100 ° C. for 20 minutes in a free state to obtain a woven fabric. Table 2 shows the density of the well and the course after the raw machine and the hot water treatment, the stretch rate and the thickness of the fabric after the hot water treatment.
[Comparative Example 1]
Polyethylene terephthalate having an intrinsic viscosity of 0.47 was melted, discharged from a 34-hole composite spinneret at a spinning temperature of 260 ° C., and taken up at a spinning speed of 2200 m / min to obtain a highly oriented undrawn yarn of 115 dtex 34 filaments. The obtained highly oriented undrawn yarn had an NDR of 56% and an elongation at break of 154%. The obtained highly oriented undrawn yarn was subjected to temporary twisting under the same conditions as in Example 1 to obtain a temporary twisted yarn.

  Table 1 shows the bulk height and the hot water shrinkage of the obtained temporary twisted yarn.

  In the same manner as in Example 1, the temporary twisted yarn obtained was used for both warp and weft to produce a plain weave fabric. This was immersed in hot water at 100 ° C. for 20 minutes in a free state to obtain a woven fabric. Table 2 shows the density of the well and the course after the raw machine and the hot water treatment, the stretch rate and the thickness of the fabric after the hot water treatment.

[Comparative Example 2]
The highly oriented undrawn yarn obtained in Example 1 was temporarily twisted under the following conditions to obtain a temporary twist yarn.
[Temporary twist condition]
Spindle speed: 300000 rpm
Temporary twist: 3450 T / m
Draft: 1.4
Temporary twist temperature: 180 ° C
Table 1 shows the bulk height and the hot water shrinkage of the obtained temporary twisted yarn.

  In the same manner as in Example 1, the temporary twisted yarn obtained was used for both warp and weft to produce a plain weave fabric. This was immersed in hot water at 100 ° C. for 20 minutes in a free state to obtain a woven fabric. Table 2 shows the density of the well and the course after the raw machine and the hot water treatment, the stretch rate and the thickness of the fabric after the hot water treatment.

[Comparative Example 3]
The highly oriented undrawn yarn obtained in Example 1 was temporarily twisted under the following conditions to obtain a temporary twist yarn.
[Temporary twist condition]
Spindle speed: 300000 rpm
Temporary twist: 3450 T / m
Draft: 1.4
Temporary twist temperature: 120 ° C
Table 1 shows the bulk height and the hot water shrinkage of the obtained temporary twisted yarn.

  In the same manner as in Example 1, the temporary twisted yarn obtained was used for both warp and weft to produce a plain weave fabric. This was immersed in hot water at 100 ° C. for 20 minutes in a free state to obtain a woven fabric. Table 2 shows the density of the well and the course after the raw machine and the hot water treatment, the stretch rate and the thickness of the fabric after the hot water treatment.

  The temporary twisted yarn of the present invention is excellent in stretchability and can provide a high-density woven fabric suitable for umbrellas and quilted base fabrics, but its application range is not limited thereto.

It is a schematic diagram which shows an example of the manufacturing process of the temporary twisted yarn of this invention.

Explanation of symbols

1 Highly oriented undrawn yarn 2 Feed roller 3 Twister 4 Delivery roller 5 Winder 6 Package

Claims (1)

Side-by-side type or eccentric core-sheath type undrawn yarn in which one component is composed mainly of polyethylene terephthalate and the other component is composed mainly of polytrimethylene terephthalate, and the glass transition of the one and other components A temporary twisted yarn obtained by drawing a temporary twist at a temperature lower than the point, and satisfying the following (1) and (2).
(1) Bulk height is 20cm ³ / g or more and less than 45cm ³ / g (2) Hot water shrinkage is 40% or more

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