JPS61296120A - Conjugate fiber - Google Patents

Abstract

PURPOSE:To obtain a conjugate fiber capable of forming ultra-fine fiber and modified cross-section fiber easily, without using chemical reagent, etc., by the melt-forming of a polymer composition containing a specific copolymerized polyester at lest a component. CONSTITUTION:The objective conjugate fiber contains a copolymerized polyester containing 8-15mol% 5-sodium sulfoisophthalate and 5-40mol% isophthalic acid and having terephthalic acid as main acid component, as at least a component. The copolymerized polyester is insoluble in cold water and soluble in hot water, has moderate heat-resistance and stringiness even at high temperature, and can be used as a component of a conjugate fiber produced by melt spinning process.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to composite fibers. More specifically, the present invention relates to composite fibers that contain hot water soluble copolymerized polyester as one component and can be easily obtained into ultrafine fibers or special circumferential cross-section yarns by removing hot water.

[Conventional technology]

Conventionally, as a method for producing ultrafine fibers, direct spinning methods are extremely difficult in terms of operability during spinning and drawing, quality of ultrafine fibers, and ease of handling up to higher processing stages, and the technology is currently limited. At this stage, it is said to be difficult. For this reason, after forming a composite mM of different components (having a cross-sectional shape of a sea-island type, a blend type, a divisible multilayer type, etc.), there is a method of dissolving and removing one component that at least partially occupies the m-dark blue surface, or dividing it by expansion. Are known.

However, it was necessary to use chemicals for the above-mentioned dissolution and removal or swelling and division. For example, conventionally, formic acid, for example, has been used to dissolve and remove polyamide, for example, a hot aqueous solution of caustic soda has been used to dissolve and remove polyester, and for example, trichloroethylene has been used to dissolve and remove polystyrene. There is.

Handling these chemicals is dangerous and requires special equipment to dissolve and remove them. This caused problems in terms of safety and health for workers and in terms of manufacturing speed.

On the other hand, in Japanese Patent Publication No. 58-39926, 20 to 60 m
It is described that a water-soluble polyester copolymerized with 5-sulfoisophthalic acid sodium salt in an amount of 0.1 mol % is blend-spun and then dissolved and removed during stretching.

However, if such a large amount of 5-sulfoisophthalic acid salt is added, foaming during the polycondensation reaction and
Since it is difficult to obtain a product with sufficient polymer polishing due to the thickening effect, the silk-spinning property was not always satisfactory.

Furthermore, since some of the material is eluted even with cold water, the molten polymer is cut by Tagawa cooling after the polymerization reaction, so water cooling cannot be used and special equipment is required.

Furthermore, as water-soluble polyester, there are many proposals for uses such as adhesives, rising agents, and paints (for example, Japanese Patent Publication No. 47
Publication No. 10873, 57-26309 @ Publication, 60-1
However, none of these methods were necessarily satisfactory for forming fibers by melt spinning.

Furthermore, Japanese Patent Publication No. 55-1374 describes water-soluble polyamides. However, this copolymer is said to be bad for yarn production due to its thermal stability at high temperatures and oligomer/seven polymer.

Especially when the water-insoluble component is polyester, it is 280 to 29.
A spinning hot stone of 0'C was required, which caused problems in thermal stability and spinning stability. Furthermore, the melt viscosity could not be maintained high, and there was a limit to the ability to maintain the cross-sectional shape of the composite yarn. In order to obtain composite yarn by melt spinning, it is necessary to have appropriate heat resistance and
It is necessary to maintain viscosity, yarn, and Jl. In particular, in composite yarns with various cross-sectional shapes, if the composition ratio of component △ and component B is set to 1* J: At least components △ and B have the same level of viscosity! You need to keep it good. If the viscosity level of both components is too high, the cross-sectional shape will be different for each single filament, or it will change with the progress of spinning, resulting in loss of stability. Furthermore, this polymer required a long time to dissolve in hot water.

That is, there is a limit to the improvement of 1li1F, a composite material in which ultrafine fibers can be obtained by easily dissolving and removing one component with hot water.

[Problem that the invention seeks to solve]

The inventors of the present invention have arrived at the present invention as a result of extensive research into composite fibers containing water-soluble polyester as one component, which do not have the above-mentioned drawbacks and have appropriate heat resistance and spinnability even at high temperatures. In particular, it is an object of the present invention to provide a composite fiber containing as one component a hot water-soluble copolyester polyester that is insoluble in cold water and easily removable in hot water.

[Means to solve the problem]

That is, the present invention provides a composite fiber consisting of at least two components, wherein at least one component of the composite fiber has a molecular weight of 8 to '15.
It is a composite fiber characterized in that it is composed of a copolymerized polyester containing mol % of 5-pttrium sulfoisophthalic acid and 5 to 4 Q mol % of isophthalic acid, and whose main acid component is terephthalic acid.

The conjugate fiber of the present invention refers to an ultra-fine fiber-generating conjugate fiber that obtains ultra-fine fibers by removing components, more specifically, sea-island composite ll1iIff, mixed spun composite 11Ii fiber, exfoliation split type conjugate fiber, etc. Multi-component composite m fibers and composite 11i that form various deformed cross sections by removing the -component.
Iff also refers to composite fibers that can be imparted with special bulkiness and firmness by removing one component from the knitted fabrics of Sera 1 to Shun.

The copolymerized polyester, which is one component of the composite fiber of the present invention, has the property of being insoluble in cold water and soluble in hot water.

This property of being insoluble in cold water and soluble in hot water is very advantageous in terms of manufacturing as a synthetic fiber. In other words, if it is soluble in cold water, when turning the molten polymer into a discharge tube after the completion of the polycondensation reaction, it will be impossible to cool the discharge in a water bath, which is commonly used, and special cooling equipment will be required. I need. For example, discharge air cooling requires a long cooling zone and a belt or loop for transporting the polymer. Requiring long cooling zones also leads to oxidative decomposition. Furthermore, when handling the composite fiber after it is made, it is deformed by moisture in the air, making it difficult to handle in post-processing. For example, in order to make ultra-fine fibers into woven, knitted or non-woven fabrics, they pass through cotton yarn or carding culms and enter the fabric forming machine, but during this process, the ultra-fine fibers may break, become fluffy, become tangled, etc. This makes processing difficult.

-〇- Therefore, since the present invention uses a copolymerized polyester of 8 to 15 mol% of 5-sodium sulfoisophthalic acid and 5 to 40 mol% of isophthalic acid, it is insoluble in cold water but soluble in hot water. ^su, and composite mM in melt spinning
It can be made with one component of 1q.

That is, the copolymerized polyester which is one component of the composite mmt of the present invention is characterized in that 5-sodium sulfoiphthalic acid and isophthalic acid are used as copolymerized components.

The copolymerization component 5-sodium sulfoisophthalic acid is 8-
15 mol%, preferably 10 to 12.5 mol%. If the amount is less than 8 mol %, a hot water-soluble product cannot be obtained. Moreover, if the amount exceeds 15 mol'X, even if it is soluble in hot water, it will be partially eluted with cold water, which is not preferable in terms of handling. Furthermore, 5-7! Requires copolymerization of 10 mol% isophthalic acid. If the isophthalic acid content is less than 5 mol %, flaky insoluble matter remains in the hot water solution 04. In addition, if isophthalic acid exceeds 40 mol%, the condensation polymerization reaction rate will be slow, the softening point of the 1q polymer will be 100'C or lower, making it difficult to dry sufficiently before melt spinning, and the melt viscosity at high temperatures will be high. There are practical problems, such as not being able to jq things.

As mentioned above, copolymerization of 5-sulfoisophthalic acid is essential for making polyester water-soluble, but this cannot be achieved without the auxiliary effect of isophthalic acid. If other components are used in place of isophthalic acid, such as alicyclic dicarboxylic acids, aliphatic dicarboxylic acids, or hydrophilic polyol components, they may swell and deform even in cold water or have poor heat resistance at high temperatures. It's hard to get what you're aiming for.

The hot water-soluble copolyester may be one that dissolves into a transparent liquid or one that becomes an emulsified finely dispersed state. In any case, it is sufficient to use hot water without using any auxiliary agents and leaving no foreign matter residues behind.

The composite fiber of the present invention is composed of the hot water-soluble polyester and a water-insoluble component. As the water-insoluble component, any polymer can be used without particular limitation as long as it has fiber-forming properties and is insoluble in water. For example, polyamides such as nylon 4, nylon 6, norylon 7, nylon 1, nylon 12, and nylon 66, polyesters such as polyethylene terephthalate 1 to polybutylene terephthalate, polyolefins such as polyethylene and polypropylene, and copolymers of these. Modified products and the like are preferably used.

In addition, this water-insoluble [(1 component is not limited to one component at all. It does not matter if there are two or more components. In any case, the hot water-soluble copolymerized polyester It is sufficient if it is a composite fiber with a certain shape.

That is, for example, when a hot water soluble copolymerized polyester is used as the sea component of a seabird composite fiber, ultrafine fibers can be obtained extremely easily by removing hot water. In addition, in the case of composite fibers in which various arrangements of hot water-soluble copolymerized polyester are considered, 1q of deformed cross-section yarn with a shape corresponding to the arrangement
You can also

-9 ~ After subjecting the knitted fabric of Zaraani Composite 1jIf to Cera 1 ~, the hot water soluble copolyester was appropriately removed to obtain a unique '1. [
It is also possible to impart a silk-like texture with bulk and waist. These are merely examples of the usage of the composite fiber of the present invention, and the present invention is not limited thereto.

〔Example〕

The present invention will be explained in detail in the following Examples. Parts in the examples mean parts by weight. The evaluation was conducted in accordance with the following method.

■ Changes in cold water: Chips (approximately 3 m...φ
After immersing a chip (x5 mm length) for 20 hours, changes in the surface condition, chip shape, and weight of the chip were observed.

(2) Solubility in hot water: 1Q of chips (approximately 3 mm φ x 5 mm) were placed in 95°C hot water 1000°C, and dissolution was observed while stirring with a magnet 1 to a stirrer.

■ Heat resistance: After vacuum drying the chip for 120'08 hours, melt it in a melt indexer at 285°C for 10 hours.
The viscosity and stringiness at 30 minutes and 30 minutes were examined.

Example 1 1 liter of terephthalate (TPA), 99.7 parts of dimethyl terephthalate (DM Ding), a methyl ester of isophthalic acid (TPA), 25.7 parts of dimethyl inphthalate (DMI), a methyl ester of isophthalic acid (TPA), ■93 ethylene glycol .3
1 part, 0°135 parts of calcium acetate into a flask]
The transesterification reaction was carried out at 30 to 230'C while distilling off the by-product methanol. Next, 5-suj, the methyl ester of 5-sodium sulfoisophthal I (SI)
~Dimethyl sulfoisophthalate (DMS I)
26.1 parts, antimony trioxide 0.03 parts, phosphoric acid 0.
0075 parts, 230~2 parts of lithium acetate 0.3 parts
After reaction at 50'C for 1 hour, condensation polymerization was carried out at 250-275°C under reduced pressure (1 ml TltlcI or less) for 3 hours. After polymerization, the polymer was discharged into a water bath at room temperature to obtain gutted chips. The thus obtained polymer had an IV (intrinsic viscosity in o, c, p solutions) of 0.92 and a softening point of 130°C. The characteristics of this chip were evaluated and as shown in Table 1,
There was no chip change in cold water, and it was soluble in hot water. Furthermore, the heat resistance was also good.

Example 2, Comparative Examples 1 to 6 Table 1 was carried out in the same manner as in Example 1 by changing the amounts of TPA, TPA, and Sr, or using adipine M (ΔA) or polyethylene glycol (PEG) instead of TPA. 1 q of copolymer polymers with various compositions shown in . The results are shown in Table 1
It was as shown in 1.

Example 3 The chip No. 14 in Example 1 was vacuum-dried for 100'C1011,1, and homopolyethylene terephthalate 1~
(P'T) Chip (IVo, 70) 150'C60)
The dried materials were separately melted (at 285°C) in a screw extruder and sent to a sea-island type spinning machine with 16 islands and 18 groups using a gear pump for composite spinning.The polymer of Example 1 was used as a sea component. The discharge amount is 5.2g/min, P"I
- is an island component, and the unstretched material was spun at 20.8 (J/min) from the die hole, air-cooled, oiled with modified A reflex, and then wound at 1000 m/min. The yarn was passed through a hot roll at 90°C and a hot plate at 120'C and drawn 3.2 times to obtain a drawn yarn of 75 denier and 18 filaments.There was almost no yarn breakage IJ1 during spinning and drawing.

Next, a tube-knitted fabric was prototyped using this drawn yarn and placed in Shimizu for 10 minutes.
After soaking for a minute, it was dried. The weight before dipping was 7.40 (knitted fabric approximately 1 m long), but after dipping treatment it became 5.9Q, and the touch was also very soft and supple. Further, the cross section of the drawn yarn was divided into ultrafine fibers of 18 filamen I and 288 filaments 1 and more.

Example 4 The cross-sectional shape of 11iIft is trilobal, and it was carried out using either the polymer of Example 1 or the spun [ ] gold which was arranged in a wedge shape tapering toward the inside of the fiber from the 111 points of the trilobal. In Example 3, 1 q of tl (75 denier, 36 filament) composite fiber is used.

Next, a tubular knitted fabric was formed according to Example 3, and then immersed in salt water for 10 minutes.
The co-car chassis poly T stell was removed, and wedge-shaped indentations were formed at the points of the three leaves that tapered in the direction of the inside of the fibers, giving it a Silk-Like 'J Yu 9rt (-B or 19 with a gloss and texture).
It was done.

〔Effect of the invention〕

Since at least one of the two or more components of the composite fiber of the present invention is insoluble in cold water and soluble in hot water, chemical agents 1. By using -1 and 4, for example, ultrafine fibers or yarn with a deformed cross section can be easily reduced to 1q.

Therefore, special 4■ safety protection equipment is not required, so the working environment is significantly improved.

In addition, a knitted fabric using the composite mlff of the present invention is also available. After cutting, the hot water soluble components are removed to obtain a processed product with a unique bulk and silk-like texture.

Claims (1)

[Claims] A composite fiber consisting of at least two components, wherein at least one component of the composite fiber contains 8 to 15 mol% of 5-sodium sulfoisophthalic acid and 5 to 40 mol% of isophthalic acid, and the main acid component is terephthalic acid. Composite fiber characterized by being composed of copolymerized polyester.