JPS5830412B2 - High shrinkage copolyester fiber and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to copolyester fibers with high shrinkage properties, particularly specific shrinkage properties, and a method for producing the same.

Shrinkable fibers are used to produce bulky yarns and bulky knitted fabrics by mixing or blending them with non-shrinkable fibers and then heat treating them at the yarn or fabric stage.

As a conventional method for obtaining shrinkable polyester fibers, a method is well known in which a copolyester obtained by copolymerizing polyethylene terephthalate with a third component is used and yarn is spun under specific conditions to obtain shrinkable fibers.

However, in conventionally known shrinkable fibers obtained using copolyester copolymerized with the third component, most of the shrinkage occurs during submersion treatment or dyeing, and the shrinkage rate is not high enough or the shrinkage is not high enough. Even if the ratio is sufficiently high, there is a drawback that sufficient bulkiness cannot be obtained because the fibers that have previously shrunk are elongated due to the influence of the process tension in the higher processing stage after dyeing.

In order to eliminate the drawback of insufficient bulkiness, the methods disclosed in JP-A-46-6458 and JP-A-4972418 reduce the shrinkage rate in hot water and increase the shrinkage rate in hot air. ,■ In Japanese Patent Application Laid-open No. 18518/1986, the shrinkage rate of boiling water measured without load is 10 or more, and the shrinkage rate of 180°C hot air measured without load after boiling water treatment is 10
Methods have been proposed in which the value is set to φ or more.

However, by any of these methods, it is difficult to obtain sufficient shrinkage and sufficient bulk required for the final product.

For example, in method (2) above, the shrinkage rate in hot water is reduced and the shrinkage rate in hot air is increased, but as a result, the total shrinkage rate is reduced in order to reduce the shrinkage rate in hot water. The problem is that it doesn't get bigger.

In addition, in the method (2) above, each shrinkage rate value is a value measured under no load, and in the actual process, a considerable amount of tension is applied, so sufficient shrinkage does not occur. No.

Furthermore, this method has a fatal flaw in that the cost increases due to the use of alkyl-substituted aromatic dicarboxylic acids.

The object of the present invention is to produce a copolyester fiber obtained by the above-mentioned known technique, which has a sufficient shrinkage rate to exhibit the bulkiness required as a final product, while eliminating the defects of the high-shrinkage copolyester fiber. The object of the present invention is to provide a copolyester fiber having a high shrinkage rate in hot water and a high shrinkage rate in hot air after shrinking in hot water at 100°C.

Another object of the present invention is to provide a method for producing the above-mentioned highly shrinkable copolyester fibers with good productivity and at low cost.

In other words, the first aspect of the present invention is to contain meta-sodium sulfoisophthalic acid in an amount of 3 mol φ or more, and a meta-sodium sulfoisophthalic acid component and other copolymer components capable of forming an ester bond with polyethylene terephthalate. total 5-2
It is made of copolyester fibers copolymerized with 0 mol φ, and the shrinkage rate (JSw) in hot water of the fibers is 8 to 2 at 100°C.
0%.

It is 13 to 26 pieces at 120℃, and the shrinkage rate (,!1fSd) in hot air after shrinking in 100℃ hot water is 1.
3-10% at 60℃, 5-13% at 180℃.

It is a highly shrinkable copolyester fiber having a shrinkage stress of 7 to 16% at 200°C and a shrinkage stress of 0.15 g/d or more when measured in hot water at io0°C.

The first characteristic of the highly shrinkable copolyester fiber of the present invention is that the shrinkage rate (JSw) in hot water (described later) is 8 to 20% at ioo°C, preferably 10 to 18.

The value is in the range of 13 to 26 φ, preferably 15 to 23 φ at 120°C, and the shrinkage stress measured in hot water at 100°C is 0.15 g/d or more.

If the JSw is less than 8 diagonals at 100°C and less than 13 at 120°C, the fibers are blended with low shrinkage fibers, formed into a woven or knitted fabric, and then heated in hot water at 100 = C or 120°C. Even if it is put into a container and processed, sufficient shrinkage does not occur, and the bulkiness is therefore unsatisfactory.

On the other hand, those whose lsw exceeds 20 at 100℃, 120
If it exceeds 26% at ℃, the quality of the thread will deteriorate significantly, and after shrinking in hot water at 100℃ or 120℃, hot air at 16%
This is undesirable because shrinkage is reduced when treated at 0° C., 180° C. or 200° C., or fibers that have shrunk during hot water treatment are elongated during hot air treatment.

The shrinkage rate (JSw) in hot water described above is
Immediately put the fiber (single yarn) coated with /d into hot water,
The shrinkage length after 10 minutes was measured and calculated as a percentage of the yarn length.

The second feature of the highly shrinkable copolyester fiber of the present invention is that the shrinkage rate (JSd) in hot air after shrinking in hot water at 100°C is 3 to 10φ at 160°C, and and 7 to 16φ at 200°C.

,! 1fSd is 3 slopes at 160℃, 5φ at 1'80℃, 2
If the fiber is less than 7φ at 00°C, even if the fiber is made into a blended yarn with a low shrinkage fiber and this is formed into a woven or knitted fabric and then treated with hot air at the above temperature, it will not shrink sufficiently and will be bulky. Sexuality becomes insufficient.

On the other hand, (Sd is 10% at 160℃, 13% at 180℃,
If the value exceeds 16 degrees Celsius at 200° C., the shrinkage due to hot air treatment will be too large and the quality of the yarn will deteriorate significantly, which is undesirable.

As mentioned above.

JSd is the fiber (single yarn) subjected to a load of 201119/d.
was immediately placed in a hot air oven adjusted to temperatures of 160°C, 180°C, and 200°C, and the shrinkage length was measured after 10 minutes and calculated as a percentage of the yarn length.

In addition, the shrinkage stress affects the ease with which yarns and knitted fabrics shrink under restraint, so the higher the shrinkage stress, the more likely they are to contract even under restraint.

The high shrinkage fiber of the present invention is io. Since the shrinkage stress measured in °C hot water is 0.15 g/d or more, the yarn or woven or knitted fabric made of the fibers will sufficiently shrink even under restraint.

In this case, if the shrinkage stress of the fibers measured in 100° C. hot water is less than 0.15 g/d, sufficient shrinkage will not occur in the constrained yarn or woven or knitted fabric.

The preferable shrinkage stress range is 0.16 to 0.40 g/d in order to make the yarn or woven or knitted fabric sufficiently bulky and to avoid the formation of cores that tend to occur due to shrinkage fibers.

More preferably 0.17 to Q and 35 g/d.

The shrinkage stress is determined by attaching the other end to a strain gauge and fixing the other end to keep the fiber at a constant length.The fiber is then placed in a hot water bath at ioOoC, and the shrinkage stress that occurs is recorded on a recorder, and the maximum value is calculated. (g/d).

Further, another feature of the high shrinkage copolyester fiber of the present invention is the use of a meta-sodium sulfoisophthalic acid component and a fourth component capable of forming an ester bond with polyethylene terephthalate as components for modifying polyethylene terephthalate.

This brings about the following two advantages.

That is, the first is that compared to the use of meta-sodium sulfoisophthalic acid or other fourth component alone, the effect can be exerted at a lower copolymerization rate when trying to obtain the same shrinkage rate.

Therefore, high shrinkage can be achieved while minimizing deterioration in properties other than high shrinkage.

Second, since the dyeability is improved, the dyeing temperature can be lowered, and as a result, the amount of shrinkage in the hot air treatment after dyeing can be increased.

The copolyester constituting the high shrinkage copolyester fiber of the present invention is composed of 3 or more moles of meta-sodium sulfoisophthalic acid component and another quaternary component capable of ester bonding with polyethylene terephthalate, and the total is polyethylene terephthalate copolymerized with components having a mole ratio of 5 to 20.

The first component here refers to a terephthalic acid component, the second component refers to an ethylene glycol component, and the third component refers to a meta-sodium sulfoisophthalic acid component, which is a compound that can form an ester bond with polyethylene terephthalate and is a component other than the above. is called the fourth component.

That is, as the fourth component, adipic acid, sebacic acid,
Difunctional carboxylic acids such as isophthalic acid and naphthalene dicarboxylic acid, diol compounds such as trimethylene glycol, diethylene glycol, polyethylene glycol, 1,4-cyclohexane dimetatool, benzoylbenzoic acid, benzyloxybenzoic acid, methoxypolyethylene Examples include monofunctional compounds such as glycol, and trifunctional or higher-functional polyfunctional compounds such as glycerin, trimellitic acid, pentaerythritol, and trimesic acid.

Note that the fourth component may be a mixture of two or more of the above compounds.

Among the fourth components, isophthalic acid, adipic acid, diethylene glycol, polyethylene glycol, and trimellitic acid are preferred.

The key is to copolymerize a meta-sodium sulfoisophthalic acid component with a mole ratio of 3 or more, and a total copolymerization amount of the meta-sodium sulfoisophthalic acid component and the fourth component to be 5 moles or more, preferably 7 It is necessary that the amount is 15 moles φ.

If the molar ratio is less than 5, the shrinkage rate will not increase, and if the molar ratio is 20 molar or more, the properties other than the shrinkage ratio will be significantly lowered.

The second invention of the present invention, that is, the method for producing the above-mentioned highly shrinkable copolyester fiber, includes the meta-sodium sulfoisophthalic acid component in an amount of 3 moles or more and another component capable of forming an ester bond with polyethylene terephthalate. A copolyester undrawn yarn copolymerized with a total of 5 to 20 moles of
This is a method of stretching at a magnification of 5 to 95 φ and then drying at a temperature lower than the stretching temperature.

The copolyesters of the invention may be produced by any method.

For example, the first reaction involves transesterification of the dimethyl ester of the acid component and ethylene glycol, or direct esterification of the acid component and ethylene glycol to produce these low polymers, and the polymerization of this reaction product. and a second reaction.

Any known catalyst is used in the first and second stage reactions, and phosphoric acid, phosphorous acid, trimethyl phosphate,
Stabilizers such as triphenyl phosphite and other additives may be added as necessary.

The characteristics of the method for producing high shrinkage copolyester fiber according to the present invention will be described below.

The relationship between the shrinkage rate of a drawn yarn in 100° C. hot water and the draw ratio for ordinary polyester is as follows: (1) When the draw ratio is gradually increased from 0, the shrinkage ratio increases as the draw ratio increases.

(2) Next, it is divided into a region B where the shrinkage rate decreases from the maximum value and a region C where the shrinkage rate reaches the minimum value and then increases slightly or changes to a saturated value.

However, the characteristics of the method for producing high-shrinkage copolyester fibers include a stretching temperature of 75°C or higher, more preferably 80 to 95°C, and a cutting ratio of undrawn yarn of 75 to 95°C.
A stretching ratio of 95φ, more preferably 80 to 90φ is adopted, and the stretching is performed in the above-mentioned region C.

(The birefringence of the obtained drawn yarn is 120×10” or more,
(Density is 1.365 or higher) When the drawing temperature is lower than 75°C, even if the drawing ratio is increased to a ratio at which the undrawn yarn breaks, region C does not appear, and as a result, the resultant drawn yarn is difficult to maintain in hot water. Even if the shrinkage rate increases, the dry heat shrinkage rate after hot water shrinkage may not increase, or in some cases, the hot water shrunk fibers may elongate (
) and the desired shrinkage characteristics cannot be obtained.

Another feature of the high shrinkage copolyester fiber manufacturing method is that
The drying temperature after stretching should be lower than the stretching temperature, more preferably 5 to 35°C lower than the stretching temperature.

If the drying temperature is higher than the stretching temperature, the shrinkage rate at each temperature will decrease, making it impossible to obtain the desired shrinkage characteristics.

The high-shrinkage copolyester fiber of the present invention has a characteristic that the bulkiness due to the shrinkage generated in the dyeing process is added to the bulkiness due to the shrinkage generated in the finishing process, and as a result, it has an extremely uniform and good quality. It is useful for obtaining bulky woven or knitted fabrics.

An example of manufacturing a bulky woven or knitted fabric using the high shrinkage fiber of the present invention will be described.

First, the high shrinkage fibers of the present invention are processed through a carding process.
40%, 70-60% non-shrink or low shrink fibers
They are mixed and subjected to a spinning process to form a blended yarn.

If a woven or knitted fabric is made from the blended yarn by a conventional method and then subjected to carrier dyeing at 100°C or high-pressure dyeing at a temperature lower than 120°C, the woven or knitted fabric will shrink significantly and develop bulk.

Furthermore, when the woven or knitted fabric is subjected to a finishing treatment in hot air at 180°C, for example, shrinkage occurs and bulkiness increases.

Another feature of the high shrinkage fiber of the present invention is that the JSw of the fiber obtained by conventionally known methods decreases by 20 to 30% from the initial JSw when left at 40°C for one month, whereas the AS
w hardly changes over time.

In addition to polyester fibers, other synthetic fibers or natural fibers may be used as the low-shrinkage fibers used in combination with the high-shrinkage fibers of the present invention.

Further, when polyester fiber is used as the low shrinkage fiber, it is preferable to use anti-pilling fiber.

Next, the present invention will be specifically explained with reference to Examples.

Example 1 A modified polyethylene terephthalate obtained by copolymerizing 5 moles of meta-sodium sulfoisophthalic acid with 3 moles of diethylene glycol was polymerized by a conventional method to obtain an intrinsic viscosity of 0.
I ended up with a 51 chip.

After drying this chip under reduced pressure at 150°C, 0.2371
m$ -1200 when discharged from a 300-hole nozzle
It was spun at r11/fillπ and was bundled into a 500,000 denier tow.

This tow was drawn in a liquid bath at a drawing temperature of 84°C and a drawing ratio of 351 (cutting ratio of 84φ), and then mechanically crimped to 75°C.
Hot air drying was performed at ℃ for 20 minutes.

This tow was cut by a conventional method to have an average size of 102 wl1, and a stable fiber having a single yarn fineness of 4 denier was obtained.

The properties of the obtained fibers were as shown in Table 1 below.

Comparative Example 1 Modified polyethylene terephthalate obtained by copolymerizing 7 mol φ of meta-sodium sulfoisophthalic acid was polymerized by a conventional method to form chips with an intrinsic viscosity of 0.51.

This chip was stretched and dried under the same conditions as in Example 1 to obtain a staple fiber having a single yarn fineness of 4 denier.

The performance of the obtained fibers is as shown in Table 2, and the shrinkage rate was small.

Example 2 Stable fiber with single yarn fineness of 4 denier obtained in Example 1 and 100°C hot water shrinkage rate of 0% obtained by another method
Single yarn fineness 3 with a shrinkage rate of 2% in hot air at 180℃
Stable fiber made of polyethylene terephthalate with a denier and cut length of 89wl1, the former 60φ
The latter was mixed at a ratio of 40φ, and spun yarn with a wire number of 60 was prepared by a conventional method, and the two yarns were twisted together to make a double yarn.

Furthermore, a jersey was knitted using this twin yarn by a conventional method.

When this jersey was dyed with a cationic dye (malachite green) using a conventional method at a temperature of 100° C. for 60 minutes, the fabric was dyed beautifully in a marbling tone and at the same time was extremely bulky.

Subsequently, finishing treatment was performed in hot air at 180°C, and the bulkiness was further increased, resulting in a fabric with a good texture.

Comparative Example 2 Processing was carried out under the same conditions as in Example 1 except that the drying temperature after stretching was 95°C, and the single yarn fineness was 4 denier and the average length was 11 J
It was made into a 2m stable fiber.

The properties of the obtained fibers were as shown in Table 3 below.

Example 3 A modified polyethylene terephthalate obtained by copolymerizing approximately 5 moles of meta-sodium sulfoisofucuric acid with 4.2 moles of isophthalic acid was polymerized by a conventional method to obtain an intrinsic viscosity of 0.5.
I made a 0 tip.

This chip was spun under the same conditions as in the example to obtain a stable fiber with a single yarn fineness of 4 denier.

The properties of the obtained fibers were as follows.

Example 4 Modified polyethylene terephthalate, obtained by diagonally copolymerizing 45 moles of meta-sodium sulfoisofucuric acid with 0.8 moles of polyethylene glycol having a molecular weight of 1000, was polymerized by a conventional method to form chips with an intrinsic viscosity of 0.49.

This chip was spun under the same conditions as in Example 1 to obtain a stable fiber with a single yarn fineness of 4 denier.

The properties of the obtained fibers are shown in Table 5 below.

Claims (1)

[Claims] 1 3 moles φ of meta-sodium sulfoisophthalic acid component
From a copolyester fiber obtained by copolymerizing the above, and a total of 5 to 20 mol φ of polyethylene terephthalate, other copolymer components capable of ester bonding, and meta-sodium sulfoisophthalic acid component, the fiber is heated in hot water. The shrinkage rate of
8~20φ at 00℃, 13~26mm at 120℃, io
The shrinkage rate in hot air after shrinking in hot water at 0°C is 1.
3-10% at 60℃, 5-13φ at 180℃, 200℃
A highly shrinkable copolyester fiber having a shrinkage stress of 7 to 16 and a shrinkage stress of 0.15 g/d or more when measured in hot water at 100°C. 2 3 moles φ of meta-sodium sulfoisophthalic acid component
An undrawn copolyester yarn prepared by copolymerizing the above and a total of 5 to 20 moles of polyethylene terephthalate and other components capable of forming an ester bond is heated at a temperature of 75°C or higher and at a cutting ratio of 75% of the cutting ratio of the undrawn yarn. A method for producing a highly shrinkable copolyester fiber, which comprises stretching at a magnification of ~95% and then drying at a temperature lower than the stretching temperature.