JPS6257921A - Polyester yarn to be crimped by water absorption - Google Patents

Abstract

PURPOSE:The titled polyester yarn having water absorption and water vapor absorption characteristics and improved bulkiness and stretchability, comprising side by side type conjugated yarn having a specific hollow part and fine pores. CONSTITUTION:The aimed polyester which is side by side type conjugated yarn comprising a polyester such as polyethylene terephthalate, polyalkylene napthalate, etc., has the hollow part C wherein the component A and/or the component B is communicate in the fiber axi direction and has the fine pores B having 0.001-5mu diameter and <=50 times as long length as the diameter arranged in the fiber axis direction in the whole crosssectional area wherein the fine pores are at least partially communicated with the hollow part C. The hollow ratio of athe hollow part C in the component A is preferably 3-50%.

Description

[Detailed description of the invention] (Industrial application field).

The present invention relates to a polyester conjugate fiber that has water absorption and moisture absorption properties, as well as excellent bulkiness and stretchability.

(Conventional technology) Conventionally, as a polyester fiber with excellent water absorption,
A hollow fiber made of polyester, having micropores scattered throughout the cross section of the hollow fiber and arranged in the fiber axis direction, the pores having a diameter of 0.001 to 5 μm and a length of Hollow fibers that are 50 times the diameter or less and at least a part of which communicates with the hollow part are known (Japanese Patent Application Laid-Open No.
6-20612).

In addition, as shown in FIG. 5, a porous component A made of polyester having micropores and a solid component B made of polyester are used.
A composite hollow fiber consisting of, at least a part of the porous component is continuous from the fiber surface to the hollow part C, and the total cross-sectional area of the porous component A in the fiber cross section is the fiber cross-sectional area (excluding the hollow part). The micropores in the porous component A have a diameter of 0.001 to 5 μm and a length of 5 μm of the diameter.
Composite hollow fibers are also known, in which the porous components are arranged in the fiber axis direction, are scattered over the entire surface of the fiber cross section, and at least a part of the porous components are connected to the hollow part C (Unexamined Japanese Patent Publication No. Publication No. 56-31017).

(Problems to be Solved by the Invention) The water-absorbing hollow fibers described in JP-A No. 56-20612 do not have crimps, so they are inferior in bulk and stretchability, and cannot be used for underwear or sportswear. I can't. Therefore, it is possible to give crimps by false twist crimping or push crimping, but when false twist crimping or push crimping is applied to hollow fibers, the stress during the crimping process causes the hollow portions to become crimped. will be crushed, resulting in a product with inferior bulk and water absorption.

On the other hand, although the side-pie-side type composite hollow fibers described in JP-A-56-31017 are composite fibers, they have a low ability to develop crimp, and can develop a high degree of crimp. It is extremely difficult to do so. Therefore, problems similar to those of the hollow fiber described in Japanese Patent Application Laid-Open No. 56-20612 arise.

The present invention solves the problems of the prior art, and produces polyester fibers that have high crimp performance, bulkiness, and stretchability without crushing the hollow portions, thus maintaining excellent water absorption. This is what we intend to provide.

(Means for Solving the Problems) The present invention provides a side-pie-side type composite polyester fiber, in which at least one component (A) has a hollow portion communicating in the fiber axis direction, and the cross section thereof Micropores arranged in the fiber axis direction are scattered throughout, and the micropores have a diameter of 0.001 to 5 μm, a length of 50 times or less of the diameter, and at least a part of them communicates with the hollow part. It is a water-absorbent crimped polyester fiber that is characterized by

Examples of the polyester in the present invention include polyalkylene terephthalate and polyalkylene naphthalate, among which the former terephthalic acid is the main acid component, and alkylene glycols having 2 to 6 carbon atoms, ethylene glycol, trimethylene glycol, etc. , tetramethylene glycol, pentamethylene glycol, and hexamethylene glycol as a main glycol component. In such a polyester, part of its acid component terephthalic acid may be replaced with another difunctional carboxylic acid. Examples of such other carboxylic acids include isophthalic acid, 5-sodium sulfoisophthalic acid, naphthalene dicarboxylic acid, diphenyl dicarboxylic acid, diphenoxyethane dicarboxylic acid, β-oxyethoxybenzoic acid,
Trifunctional aromatic carboxylic acids such as p-oxybenzoic acid, difunctional aliphatic carboxylic acids such as sepasic acid, adipic acid, and oxalic acid, difunctional alicyclic carboxylic acids such as 1,4-cyclohexanedicarboxylic acid, etc. can be mentioned. Further, a part of the glycol component of the polyester may be replaced with another glycol component, and such glycol components include the above-mentioned glycols other than the main component and other diol compounds, such as cyclohexane-1-4-dimetatool, neopentyl glycol, Examples include aliphatic, alicyclic, and aromatic diol compounds such as bisphenol A and bisphenol S, and polyoxyalkylene glycols.

Such polyesters can be obtained by any manufacturing method. For example, regarding polyethylene terephthalate, terephthalic acid and ethylene glycol may be directly esterified, a lower alkyl ester of terephthalic acid such as dimethyl terephthalate may be transesterified with ethylene glycol, or terephthalic acid and ethylene oxide may be transesterified. The first stage reaction is to react with the glycol ester of terephthalic acid and/or its low polymer, and then the product is heated under reduced pressure to perform a polycondensation reaction until a desired degree of polymerization is achieved. It is easily produced by a two-stage reaction.

The polyester fiber of the present invention is a side-pie-side type composite fiber consisting of component (A) and component (B) as shown in FIGS. It has a hollow part (C) that communicates with the. FIG. 2 shows an example in which the component (B) also has a hollow portion (C'). In addition, component (A) has micropores (V) arranged in the fiber axis direction scattered throughout its cross section, and the micropores (V) have a diameter of 0.001 to 5 μm and a length of 5 in diameter
0 times or less, and at least a portion of it must communicate with the hollow portion (C).

If the hollowness ratio of the hollow part (C) in component (A) is too low, the effect of improving water absorption and hygroscopicity will decrease, and if it is too high, the hollow part (C) will be easily crushed, and once crushed, the water absorption will be reduced. properties and hygroscopicity will decrease. Therefore, the hollowness ratio is
A range of 5 to 50% is preferred. Furthermore, if the diameter of the micropores (V) is less than 0.001 μm, the water absorption and hygroscopic effects are reduced, and if it exceeds 5 μm, sufficient fiber strength cannot be obtained. In particular, a range of 0.01 to 3 μm is preferred. Also,
If the length of the micropores (V) exceeds 50 times the diameter, it is unsuitable because the strength and fibril resistance of the fiber will decrease, and a length of 30 times or less is particularly preferred. Furthermore, the fine pores (V) are scattered throughout the cross section of the component (A), are arranged in the fiber axis direction, and at least a part of them communicates with the hollow part (C), thereby providing sufficient water absorption. Provides hygroscopic properties.

The above-mentioned polyester component A having micropores (V) is disclosed in, for example, JP-A-57-11212, JP-A-57-139.
It is manufactured by the method disclosed in Japanese Patent No. 516. That is, as a typical example, a polyester composition obtained by blending a micropore-forming agent with polyester in an amount of 2 to 14 mol % based on the acid component constituting the polyester is used as a fiber, The resulting fiber is then treated with an aqueous solution of an alkaline compound to elute at least 2% by weight.

As the micropore forming agent, a compound represented by the following general formula can be used. In the above formula, M
and M' are metals, and M is preferably an alkali metal, a group Ⅰ metal of the periodic table, Mn'/z, Co'/z, and among them, L i , Ca'/2, M g
172 is particularly preferred. As M', alkali metals and alkaline earth metals are preferable, and among them, Li, Na, and K are particularly preferable. M and M' may be the same or different. n is 1 or 2. R is a hydrogen atom or an ester-forming functional group, and the ester-forming functional group is 100OR' (where R' is a hydrogen atom, an alkali group having 1 to 4 carbon atoms, or a phenyl group) or -Co ( -0(CH
z )ヱ ]POH (However, p is an integer greater than or equal to 2, and p is 1
or larger integer), etc. are preferable.

Preferred specific examples of such compounds include Na 3-carbomethoxybenzenesulfonate, Li 5-carboxylate,
3-carbomethoxybenzenesulfonic acid, -5-carboxylic acid K, 3-carbomethoxybenzenesulfonic acid Na-
5-carboxylic acid Cal72.3-carbomethoxybenzenesulfonic acid Na-5-carboxylic acid Mg'/z, 3-hydroxyloxycarbonylbenzenesulfonic acid Na
-5-carboxylic acid Mgl72.3-carboxybenzenesulfonic acid Na-5-carboxylic acid Mn'/Z, 3-hydroxyethoxylponylbenzenesulfonic acid Na=
5-carboxylic acid Zn'/z, benzenesulfonic acid Na
-3,5-di(carboxylic acid Li), benzenesulfonic acid Na a-3,5-di(carboxylic acid 1), benzenesulfonic acid Na -3,5-di(carboxylic acid K), benzenesulfonic acid Na -3,5-di(carboxylic acid ca'/z)
, Na3゜5-di(Mg carboxylate) benzenesulfonate
'/z) etc.

In the side pie side type composite fiber of the present invention,
It is desirable that the high shrinkage component of the side pie side components be a high [μ] polyester with a high intrinsic viscosity, and the low shrinkage component be a low [μ] f polyester with a low intrinsic viscosity. In this case, it is desirable that the difference in intrinsic viscosity is 0.02 or more. In particular, for high shrinkage components, the intrinsic viscosity difference is 0.64
or higher [η].

Polyester is used as the low shrinkage component, and polyester is used with a low intrinsic viscosity of 0.45 or less [η], and the intrinsic viscosity difference is 0.1.
It is preferable that the number is 9 or more.

In addition, the high-shrinkage component is low-crystalline polyethylene terephthalate copolymerized with isophthalic acid, diethylene glycol, etc., and the low-shrinkage component is polyethylene terephthalate or high-crystalline polyethylene terephthalate, which is added with an oriented crystal accelerator such as sodium alkyl sulfonate or polyethylene. It is also a preferred embodiment to use polyethylene terephthalate.

Usually, when the spinning speed is low (700 to 1,300
m7 minutes), the former combination is suitable, and when the spinning speed is high (2,500 m7 minutes or more), the latter combination is suitable.

Furthermore, in the composite polyester fiber of the present invention, the composite ratio of component (A) and component (B) is preferably 0.6 to 3.

The hollow composite spinning device used in melt spinning may be any conventionally used device.

For example, to spin the conjugate fiber shown in FIG. 1, the spinneret nozzle shown in FIG. 3 may be used, and to obtain the conjugate fiber shown in FIG. 2, the spinneret nozzle shown in FIG. 4 may be used. In FIGS. 3 and 4, component A (low shrinkage component) is spun from part A', and component B (high shrinkage component) is spun from part B'.

Here, the shape and dimensions of the spinneret nozzle are selected so that the hollow ratio of the hollow portion in component (A) is 3 to 50%.

In addition, in order to bond both composite components, JP-A-58-13
As shown in Japanese Patent No. 720, a method is preferably used in which both components are separately discharged from a nozzle of a mouthpiece, and after being discharged, they are brought together by colliding with each other on or directly below the mouthpiece surface.

The composite polyester fiber melt-spun in this way is
Stretching heat treatment is performed as necessary, and then crimp processing is performed using a heated fluid pushing nozzle or the like.

In addition, the polyester fiber of the present invention is produced by producing side-pie-side type composite polyester fiber by high-speed melt spinning for 4,000 m or more for 7 minutes, and then crimping it as it is by using a heated fluid forcing nozzle or the like without stretching. It can also be obtained by

(Function) The polyester fiber of the present invention is a side-pie-side type composite fiber, in which one component (A) has a hollow portion communicating in the fiber axis direction, and the entire cross section has a hollow portion that communicates in the fiber axis direction. The micropores have a diameter of 0.001 to 5 μm, a length of 50 times the diameter or less, and at least a part of which communicates with the hollow part, so that water absorption is prevented. In addition to having extremely good properties and moisture absorption, the side
Since it has a pie-side type composite structure, it has excellent crimpability, bulkiness, and stretchability.

In this way, polyester fibers having both excellent water absorbency and crimpability can be obtained.

(Example) Hereinafter, the present invention will be explained in detail by giving examples. Incidentally, the measured values in the examples were determined by the following method.

(1) Total crimp rate (TC) O 10 is treated in spring water for 20 minutes with a load of 2 mg per de, dried at 40°C or less for one day and night, and then reduced to 2 mg per de.
This is the length after 1 minute after applying a load of 00 mg.

1 is the length after 1 minute after applying a load of 2 mg per de 3 minutes after 10 measurements.

(2) Crimp number 20 single yarns were taken from the crimped yarn, and 25
Take a photo enlarged twice, measure the number of crimps, and measure the number of crimp.
The average value of 0 pieces was calculated.

(3) Water absorption rate (according to JIS-L1018) The fibers are made into a cloth, and the cloth is soaked in a 0.3% aqueous solution of anionic detergent Zab (manufactured by Kao Soap Co., Ltd.) at 40°C in a household electric washing machine.
Repeat washing for 30 minutes at a specified number of times, then dry the resulting sample horizontally, and drop 1 drop (0.04 cc) of water from the height of the 1 mark above the sample until the water is completely absorbed into the sample. Measure the time until reflected light is no longer observed.

(4) Water holding rate The sample obtained by drying the fabric is immersed in water for 30 minutes or more, and then dehydrated for 5 minutes in a dehydrator of a household electric washing machine. It was calculated from the weight of the dry sample and the weight of the sample after dehydration using the following formula.

Example 1.2 Comparative Example Component (A): Na-3,5 benzenesulfonate
Polyethylene terephthalate having an intrinsic viscosity of 0.66 and polyethylene terephthalate having an intrinsic viscosity of 0.45 as component (B) in which 1% by weight of -di(galponic acid Mg'/z) is dispersed are separately melted, and a third Using the spinneret nozzle shown in FIG.
Discharge bonding is performed in step 1, followed by cooling and oiling, and step 9.
It was pulled at a speed of 40 m/min. After that, instead of winding it up, it was preheated to 95°C and then stretched at 3.1 times.
Heat centrifugation was carried out at 120°C, and then the 75 denier/24 filament side-pie-side type composite polyester composite fiber was produced by pressing it into a pushing nozzle with hot air at 210°C under 10% overfeed to develop crimp. Obtained. This composite fiber has a cross-sectional shape as shown in FIGS. 1 and 2, and the composite ratio of component (A) and component (B) is 1:
1, and the number of crimp and total crimp rate (TC) were as shown in the following table.

This composite fiber is knitted into stockinette fabric, refined by conventional methods,
After presetting, the sample was treated with a 3% by weight aqueous sodium hydroxide solution at boiling temperature so that the weight loss rate was 20% by weight.

When the single fibers of this alkali-treated cloth were enlarged with an electron microscope, micropores arranged in the fiber axis direction were scattered throughout the cross section of component (A), and the average diameter of the micropores was 0.7 μm, and the average length of the micropores was 0.7 μm. The diameter was 15 μm, and at least a part of it communicated with the hollow part. Incidentally, the hollow ratio of the hollow portion of component (A) was 25%.

Next, this alkali-treated cloth was dyed under the following conditions.

Dyeing conditions Dye: Sumikalon Navy Blue S-2GL (Sumitomo Chemical Co., Ltd. 26% OWf 1) Non-ionic dispersant: Disper VG (Meisei Kasei Kogyo (Kikki): 1 g/J pH adjuster: Acetic acid: 0.2 cc/ I! Bath ratio: 1:
3. Processing bath temperature: 130°C. Processing time: 260 minutes. Thereafter, neutralization, washing, and drying were carried out using conventional methods.

The water absorption rate and water retention rate of the obtained fabric were measured and the results are shown in the following table.

On the other hand, for comparison, hollow fibers made only of polyester constituting component (A) of Example 1 (Comparative Example 1) and hollow fibers subjected to false twisting by a conventional method (Comparative Example 2) The results of the same experiment as in Example 1 are also shown in the following table.

(Wood page, blank space below) [- As is clear from the table, the hollow fiber made only of component (A) (Comparative Example 1) had good water absorption performance, but had almost no crimp. The bulkiness and stretchability of the fabric were extremely poor.

When the hollow fibers of Comparative Example 1 were false-twisted in a conventional manner to impart crimps (Comparative Example 2), the hollow portions were swollen, resulting in a significant drop in water absorption performance.

However, the composite polyester fiber of the present invention (Example 1.2) had excellent crimp performance and water absorption performance.

(Effects of the Invention) The polyester fiber of the present invention has both excellent water absorption and shrinkability, and has good bulk and stretch properties, and is suitable for use in fields such as underwear and sportswear. can do.

[Brief explanation of drawings]

Figures 1 and 2 are cross-sectional views showing examples of the polyester fibers of the present invention, and Figures 3 and 4 are spinnerets used when spinning the polyester fibers of Figures 1 and 2, respectively. The plan view of the nozzle and FIG. 5 are cross-sectional views showing conventional polyester composite hollow fibers. A...component (A), B...component (B), C...hollow part, ■...micropore, A'... ...Component (A) spinning section, B'...Component (B) spinning section.

Claims (1)

[Claims] 1. A side-by-side type composite polyester fiber, in which at least one component (A) has a hollow portion communicating in the fiber axial direction, and the whole cross section has a hollow portion communicating in the fiber axial direction. Arranged micropores are scattered, and the micropores have a diameter of 0.
．． 001 to 5 μm, the length is 50 times or less the diameter,
A water-absorbing crimpable polyester fiber, characterized in that at least a portion thereof communicates with the hollow portion. 2. The water-absorbing crimpable polyester fiber according to claim 1, wherein the hollow portion of component (A) has a hollow ratio of 3 to 50%. 3. Claim 1 or 2, wherein the difference in intrinsic viscosity between one component (A) and the other component (B) is 0.02 or more
The water-absorbing crimpable polyester fiber described in Section 1. 4. The water-absorbing crimpable polyester fiber according to claim 3, which has an intrinsic viscosity difference of 0.19 or more.