JPH03269110A - Cation-dyeable fiber - Google Patents

Abstract

PURPOSE:To obtain the subject fiber, composed of a modified copolymer having groups, electrolyzable into anions in water in a specific proportion and bonded to side chains of an ethylene-vinyl alcohol-based copolymer and having excellent hand. CONSTITUTION:The objective fiber obtained by spinning an ethylene-vinyl alcohol-based copolymer with 30-70mol% ethylene unit content or carrying out conjugate spinning of the aforementioned copolymer and other crystalline thermoplastic polymers (preferably nylon 6, etc.) at (10:90)-(90:10) weight ratio, preferably forming a fabric from the resultant fiber or conjugate fiber and then introducing or bonding groups (preferably sulfuric acid ester, etc.) electrolyzable into anions in water in an amount of 0.5-30mol% based on the total number of mol of ethylene units and vinyl alcohol-based units into side chains of the ethylene-vinyl alcohol-based copolymer according to acetalization, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a sulfethylene-vinyl alcohol copolymer fiber that has a good texture and is dyeable with cationic dyes. More specifically, by reacting anionic compounds to fibers made of a saponified ethylene-vinyl acetate copolymer, we have developed bright colors and light-gathering properties that are not found in conventional synthetic fibers. This invention relates to a technology that makes it possible to impart dyeability with cationic dyes.

(Prior art) Conventionally, fiber structures such as woven fabrics, knitted fabrics, and non-woven fabrics made of synthetic fibers m1, for example, polyester and polyamide filaments, have a single filament denier and a cross-sectional shape that are similar to cotton, linen, etc. Compared to other natural fibers, the texture and luster were monotonous and cold, and the quality as a fiber #a structure was low.

In addition, synthetic fiber Fi produced by melt spinning has a specular luster, and even when dyed, natural fibers such as wool and silk #! It had the disadvantage that it was difficult to obtain the vividness and depth of colors compared to the conventional method.

(Problem to be solved by the invention) In recent years, in order to improve these drawbacks, 11! Although many attempts have been made to develop a different shape fL in the feeding cross section, crimping, composite fibers, etc., the current objective has not yet been fully achieved. For example, Japanese Patent Publication No. 56-165015,
JP-A-57-5921, JP-A-58-98425
Forming composite fibers of easy-to-width polymer and polygosal as described in Publication No. 61-239010, %Kaida No. 61-239010, etc. The luster can be imparted to the woven or knitted fabric 1 (or, as shown in Japanese Patent Publication No. 51-7207, Japanese Unexamined Patent Publication No. 70711-1982, Japanese Unexamined Patent Publication No. 133118-1987, etc.) A method of improving the texture by imparting unevenness in the direction, or Special Publication No. 53-3
As shown in Japanese Patent Publication No. 5633, Japanese Patent Publication No. 56-], Japanese Patent Publication No. 6231, etc., the ability to fibrillate Imanari rut fibers and improve the texture is also reported in Japanese Patent Publication No. 18072-1987.
As proposed in the publication, one false-twisted, fused yarn is prepared,
A method for imparting crispness to a dismantling machine, or JP-A-63
- A method for producing J'uni mixed fiber fused processed yarn shown in Publication No. 61.23, where b is % rA 1986-611
Fibrillation method as shown in Japanese Patent Publication No. 59-2423
A variety of methods have been proposed, including methods to reduce surface gloss and increase color depth. l, Synthesis while nudging #I! Kawafuzu believes that it is sufficient to give textiles a texture and color development similar to those of natural fibers.

In particular, it has been an unprecedented task to impart texture and color development similar to natural hemp IIA fibers and natural cotton fibers.

Moreover, since synthetic fibers such as polyester have insufficient hydrophilicity, they are actually inferior to cotton in terms of comfort.

The present invention provides synthetic rutted fibers with hydrophilicity by combining them with polymers having hydroxyl groups (OH groups), giving them a soft and bulky feel, and making them more similar to natural fibers! gained strength,
Moreover, it has excellent color development after dyeing, and has excellent eaves and eaves.
The aim is to obtain self-made line embroidery that can exhibit light-gathering properties in rainbows.
For this purpose, we have investigated the polymer design, manufacturing conditions and post-processing conditions that will cause no problems in the cording process.

The above purpose can be achieved by using a saponified product of ethylene-vinyl acetate copolymer as a polymer that can achieve the above purpose, and after making it into fibers, chemically bonding anionic groups and imparting dyeability with cationic dyes. Although it has become possible, we have determined what materials should be used and what configuration conditions should be used in order to achieve the purpose.

(Means for Solving the Problems) That is, the present invention has a basic skeleton of an ethylene-vinyl alcohol copolymer, and an atomic group having a group that can be electrolyzed into N ions in water is bonded to the 1IIl chain. and the amount of ethylene units occupying the basic skeleton is 30 to 70 moles, and the amount of groups that can be electrolyzed into ions in water is equal to the total number of moles of ethylene units and vinyl alcohol units constituting the basic skeleton. It is made of a modified ethylene-vinyl alcohol copolymer with a molecular weight of 0.5 to 30 molar mass, and is composed of such a copolymer and other crystalline thermoplastic polymer and its weight Ratio is 10:90-90
:10, and the copolymer is exposed on at least a portion of the surface of the conjugate fiber.

First, the above ethylene-vinyl alcohol i-a copolymer, that is, the saponified product of ethylene-vinyl acetate copolymer (hereinafter referred to as A
In detail, the polymer (sometimes referred to as a polymer) has a high degree of saponification of over 95, and an ethylene content of 30 to 70.

ruchi, that is, the vinyl alcohol component is 30 to 70
The one made from malt is the best. If the content of the vinyl alcohol component in the A polymer decreases, properties such as hydrophilicity will naturally decrease due to the decrease in hydroxyl groups (1), and as will be described in detail later, it is difficult to achieve the desired good hydrophilicity. This is undesirable because the natural fI and fiber-like texture cannot be obtained. However, when the vinyl alfur component content increases,
Melt formability deteriorates, spinnability becomes poor during fiberization, and single filament breakage and yarn breakage occur frequently during spinning or drawing, which is undesirable. In addition, as will be described in detail later, when composite spinning is performed with Polymer A and other melt-formable poly(Z--(referred to as B Polymer)), if a high melting point polymer such as polyethylene terephthalate is used in combination with B polymer, the spinning temperature will be lower. is 250° C. or higher, and if the vinyl alcohol component is large, the heat resistance at 250° C. or higher will also be insufficient, which is also not suitable. Therefore, it can be said that a compound having a high degree of conversion and a vinyl alcohol component content ranging from 30 to 70 moles is suitable for obtaining the desired am.

In order to stably spin the A polymer continuously for a long time,
It is necessary that the mbolimer has sufficient heat resistance. In particular, when performing composite spinning, when a high melting point polymer such as polyester or polyamide is used as the B polymer, the composite fiber with the polymer is made by continuously spinning the composite fiber for a long time. It has been found that as a means to further improve heat resistance, it is effective to set the vinyl alcohol component content within an appropriate range, and furthermore, to reduce the metal ion content in the A polymer to a predetermined content or less. Thermal decomposition Wk* of polymer A can be roughly divided into two mechanisms: one in which a cross-linking reaction occurs between polymer chains and saponified products are generated, and the other in which decomposition progresses through main chain scission and side chain detachment. It is thought that they occur in a mixture. Although the details will be omitted, it has been found that by removing the metal ions in Polymer A, the thermal stability during melt spinning can be dramatically improved. In particular, group 1 alkali metal ions such as Na", K" ions, Ca"Mg
It has been found that a significant effect can be obtained by controlling the content of group (I) alkaline earth metal ions such as 2+ ions to 100 ppm or less. %K, Ae during continuous melt spinning under high temperature conditions for a long time.

When gelled substances are generated in the polymer, they gradually clog and accumulate on the spinning filter, resulting in a sudden increase in the spinning pack pressure and shortening the nozzle life, as well as single fiber breakage and breakage during spinning. Threads will occur frequently. If the gelation further progresses, the polymer piping may become clogged, which is undesirable. By removing Group Ⅰ alkali metals and Group Ⅰ alkaline earth metals in A polymer, large amounts of gelation can be achieved even during long-term continuous operation during melt spinning at high temperatures and I# melt spinning at 250°C or higher. It was found that troubles caused by this outbreak were less likely to occur. Preferably Fi, each less than s o ppm.

We prefer each to be 10 ppm or less.

The method for producing polymer A is, for example, by radically polymerizing ethylene and vinyl acetate in a polymerization solvent such as methanol under a radical polymerization catalyst, then expelling unreacted monomers, and then silica using a caustic powder. After reacting with the ethylene-vinyl alcohol copolymer, it is pelletized in water, washed with water, and dried. Alkali metals and alkaline earth metals tend to be present in polymers due to the process, and usually several hundred ppm or more of alkali metals and alkaline earth metals are mixed in. A method for removing as much alkali metal ion and alkaline earth metal ion content as possible is to pelletize after saponification during the polymer production process, and then wash the pellet in large quantities with a pure aqueous solution containing wet pellet th acid. , can be obtained by washing the pellet in large quantities with only a large excess of pure water.

Further, it is preferable that the A polymer is produced by saponifying the copolymerization of ethylene and vinyl acetate using a caustic powder, and the degree of saponification at this time is preferably 95 or more. When the degree of saponification decreases, not only does the crystallinity of the polymer decrease and fiber physical properties such as strength decrease, but also the polymer A tends to soften, causing problems in processing and drawing, and the resulting thick #llW The texture of the structure also deteriorates, which is not desirable.

In the present invention, the A polymer may be used alone, or it may be combined with other melt-moldable polymers depending on the purpose. As the B polymer, it is preferable to use a thermoplastic crystalline polymer having a melting point of 150° C. or higher from the viewpoint of heat resistance and dimensional stability. The polymer B having a melting point of 150° C. or higher may be any polymer having a melting point of 150° C. or higher and having good 1111m formation properties, such as polyester, polyamide, polybrohylene, etc. Preferably, it is a polyester based on polyethylene terephthalate or polyethylene terephthalate, or a polyamide based on nylon 12, nylon 6, or nylon 66.

Examples of polyester include terephthalic acid.

Isophthal 52. Naphthalene-2,6-dicarboxylic acid, phthalic acid, α, β-(4-carboxyphenoxy)
Aromatic dicarboxylic acids such as ethane, 4,4-dicarboxydiphenyl, 5-sodium sulfoiphthalic acid or adipic acid, aliphatic dicarboxylic acids such as sepacin a or their esters, ethylene glycol, diethylene glycol, 1, 4-phytane diol, 1
．． #l synthesized from diol compounds such as 6-hexanediol, neopentyl glycol, cyclohexane-1,4-simethanol, polyethylene glycol, and polytetramethylene glycol! ! Made of formable polyester.

Polyesters in which 80 molar units or more, even 90 molar units or more of the structural units are ethylene terephthalate units or ethylene terephthalate units are preferred. The polyester may also contain small amounts of additives, fluorescent whitening agents, stabilizers, ultraviolet absorbers, and the like.

In addition, polyamides include nylon 6, nylon 66,
It may be a polyamide containing nylon 12 as a main component, or a polyamide containing a small amount of a third component. These may contain small amounts of additives, fluorescent brighteners, stabilizers, etc.

Moreover, the composite ratio of the A polymer and the B polymer is preferably 10 to 90 by weight based on the ratio of the A polymer.

If it is outside this range, the composite ratio will be unbalanced and spinnability will be poor, which is not preferable.

Next, an example of a composite shape will be shown. Model diagrams of specific composite forms are shown in FIGS. 1 to 1 as examples.

1 and 2 are core-sheath type cross sections. FIGS. 3 and 4 are composite cross-sections of the bonded type. Figures 5 to 7 show multilayered composite cross sections, and depending on the selection conditions of polymer A and polymer B, it is possible to divide the cross section into ultra-thin layers. Figures 8 to 11
The figure shows a type in which the fiber is split toward the center of the fiber cross section, and shows a type in which only the A polymer component is split or only the B polymer component is split. Figure 12 shows an example of a hollow cross-section fiber, in which the A polymer component and the B polymer component are arranged in an annular shape.
He is the type to get a KO. FIG. 13 shows an example of a type in which the A polymer component and the B poly 7-component are each divided toward the center of the fiber cross section.

FIG. 14 and FIG. 15 are examples of composite shapes of irregular cross section * separation. FIG. 16 is an example of a composite shape of a heterogeneous mixture of A polymer and B polymer. This can be obtained by appropriately dividing the A polymer and the B polymer into layers using a 4- to 8-element static mixer immediately before discharging them from a spinning nozzle, and then discharging them from a nozzle hole. FIG. 17 is an example of a core-sheath composite shape in which the core component is B polymer and the sheath component is a polymer blend component of A polymer and B polymer. In the case of such composite fibers, in order to exhibit the hydrophilicity and hand-improving properties of Polymer A, at least a portion of the surface of the composite fiber, preferably at least 10 inches of the surface, must be covered with Polymer A. is necessary.

Another xg in this invention! What is important is that an atomic group having a group that can be ionized into an anion in water (hereinafter referred to as an anionic group) is bonded to the A polymer molecule. Examples of ionic groups include sulfuric acid esters, sulfonic acid groups, sulfinic acid groups, phosphonic acid groups, phosphinic acid groups, and salts thereof, phenolic water ea and salts thereof, sulfates, esters such as phosphates, and esters thereof. There are salts, but in order to bring about the effects described in the present invention, sulfuric esters, sulfonic acids, or salts thereof are particularly preferable. When the above-mentioned anionic group is bonded to the A polymer molecule and dyed with a cationic dye, a color is developed that develops color depth, vividness, and light-gathering properties that cannot be obtained with conventional synthetic rut edges. It was discovered that fibers with properties can be obtained.

The reason for the wonderful color development described above is HA! Although it is not possible to say at this time, one thing is that the molecular extinction coefficient (ε) of the original dye (Textile and Industry S 69, 2.46) is about 2.
8XlO' Anthraquinone disperse dye is approximately 1.3
Compared to XlO', cationic dyes are larger at about 4.7×10 4 , and cationic dyes absorb more light and reflect less, so they are more likely to develop a deep yellow color than disperse dyes. Regarding this, it is known that polyester fibers made by copolymerizing polyester with sodium 5-sulfoiphthalate and dyed with cationic dyes have greater color depth than conventional polyester fibers dyed with disperse dyes. However, in the case of such fibers, the vividness and depth of the colors have not reached the level that can be achieved.

The reason why the fibers of the present invention exhibit better color development than conventional cationically dyeable polyester fibers is thought to be due to the relationship with the refractive index of the polymer. The refractive index of polyester fiber is 1.73 and that of silk is 1.59, whereas the I/Ik of fibers made from Mborimer varies slightly depending on the ethylene content, but is around 1.5, which is lower than other fibers. . As is well known in post-processing agents for textile products, the fact that the refractive index is low is that when a low refractive index material is applied to the surface of a fiber, it will cause the same effect as when wet with water, which is generally said to be the case. A different color appears when wet, bringing about the effect of making the dyed product even more vivid. Since Polymer A has a low refractive index, we believe that a synergistic effect is developed when combined with the high molecular extinction coefficient of the cationic dye, resulting in color development with excellent color depth and vividness. . Furthermore, in the case of polymer A having transparency with a low refractive index that is imparted as a cationic dye, it is colored with a cationic dye that exhibits a fluorescent color.In some cases, the polymer absorbs direct light and dispersed light from the surroundings. Inside, it is effectively emitted as fluorescent light, giving it a fluorescent color with a strong brilliance.Surprisingly, when viewed from the cross-sectional direction of the fiber, it also has a bright color tone with light-gathering properties. This is what was discovered. These facts were discovered for the first time during intensive study by the present inventors, and were previously unknown.

As a method for imparting anionic groups to the polymer A, a vinyl hexamer or oligomer containing anionic groups can be used and introduced into the polymer forming the fiber.

Alternatively, it may be introduced after polymerization, after fiberization, or even after fabrication. Preferably, it is after being made into a fiber or a fabric.

In addition, photoreaction or radiation may be used to introduce anionic groups, or acetalization, esterification, sulfonation,
Known reactions such as oxidation and grafting may be used. To give a specific example, after forming a fabric made of fibers made of polymer A, it is subjected to an acetalization reaction treatment using, for example, O-benzaldehyde sulfonic acid sodium salt. It is preferable to use a strong acid such as sulfuric acid as an acetalization reaction catalyst. As a compound for introducing an anionic group using an acetalization reaction, a monoaldehyde or dialdehyde compound having a sulfuric acid ester group, a sulfonic acid group, or a salt thereof is preferable.

The content of anionic groups in the polymer is more than 0.1 mol 30 mol, preferably from 1 to 10 mol. The content of anionic groups referred to herein is the ratio of the number of moles of anionic groups to the number of molecules (ie, ethylene units and vinyl alcohol units) on the basic skeleton unit of the A polymer forming the fiber. If the content of the anionic group is less than 0.1 mole, the cationic dye will not be able to fully absorb the dye, so that a sufficiently deep color cannot be obtained, which is not preferable. On the other hand, 30
Exceeding the momol level is not preferable because the swelling of the am in water becomes large and the dimensional stability of the gap deteriorates, and adhesion between the single fibers occurs, making the fabric hard and deteriorating its feel.

Furthermore, human polymers are polymers with a melting point of around 150 to 180°C, and the melting point actually decreases in hot water, and they tend to soften even below 150°C. Therefore, depending on the processing conditions, a softening phenomenon may occur, leading to a sticking phenomenon between single fibers. If it is desired to adjust the hardness of the texture due to the sticking phenomenon, it is possible to perform a molecular crosslinking treatment on the A polymer to improve the heat resistance and hot water resistance. For the crosslinking reaction, known general methods can be used; for example, crosslinking using an organic crosslinking agent such as a divinyl compound, formaldehyde, dialdehyde, diincyanate, or an inorganic crosslinking agent such as a boron f arsenide; γ
Examples include crosslinking reactions caused by radiation edges such as wires and electron edges, and by light. A crosslinked structure can be introduced by copolymerization with a polymer having a crosslinked structure in advance. Further, during polymerization, a crosslinking reaction can also be carried out after fiberization. As a preferred example, it is convenient to carry out the acetalization reaction after forming the fabric consisting of 1IRII with the A polymer.

An example of specific conditions for acetalizing the Ia fibers of the present invention is that a strong acid such as sulfuric acid, formic acid, or hydrochloric acid is used as the acetal fFS reaction catalyst, and the concentration of the strong acid used is 1 to 0. Set below. The aldehyde represented by the dialdehyde compound represented by 0HC-CnHzyx-CHO (n = 0 to 10) is
．． As a solution with a concentration of 2f/1 or more and 5oot and 'n or less,
It is preferable to process the fibers at a reaction temperature of 15°C or higher and 135°C or lower. When dialdehyde is used as the aldehyde, the acetalization reaction with the dialdehyde may leave non-crosslinking type 7-aldehyde in addition to the crosslinking reaction, and this aldehyde heats the color fading of the dyed material. Time-occurrence L7 may occur. In order to prevent this, it is preferable to oxidize the free aldehyde with an oxidizing agent to convert it into I2 carboxylic acid or carboxylate. Of course, as mentioned above, as the aldehyde used for this acetalization, it is most preferable to use an aldehyde compound having a group capable of anion KW decomposition in water, such as sodium benzaldehyde sulfonate.

Furthermore, when polyester is used as the B polymer and dyed as a composite fiber at high temperature and high pressure, if undesirable shrinkage of the fabric based on the A polymer component part occurs under high temperature hot water conditions, Undesirable shrinkage during dyeing can be prevented by the presence of a salt of a strong acid or strong base or boric acid, either alone or in a mixture of both.

In the present invention, the basic skeleton is referred to as an ethylene-vinyl alcohol copolymer because, as mentioned above, the copolymer can be obtained by saponifying an ethylene-vinyl acetate copolymer. However, depending on the strength of the chain, a small amount of vinyl acetate units may remain in the copolymer, and other copolymers may be present. Because an atomic group having a group that can be electrolyzed into an ion is bonded to it, the hydrogen atom of the hydroxyl group of the vinyl alcohol is replaced by the atomic group, or it has a group that can be electrolyzed into an anion in water. This is the result of taking into account that there are cases where a monomer having an atomic group as a side chain is copolymerized into an ethylene-vinyl alcohol copolymer, and the above expression is used to include all of these.

The main uses of the short fibers obtained in the present invention include staples for clothing, dry-laid nonwoven fabrics, and wet-laid nonwoven fabrics. Of course, the 111 fiber of the present invention may be used as 1004, or the effect of the fiber of the present invention can be obtained by using a portion of the fiber of the present invention and applying it to other twill lines to produce a nonwoven fabric or the like. However, it goes without saying that the effects described in the present invention may not be fully obtained unless the fibers of the present invention are mixed in a certain proportion or more. Furthermore, the fibers of the present invention can be used as long fibers to provide good color development and good texture, making them ideal for fabrics such as woven or knitted fabrics for outerwear and the like.

Furthermore, the fibers obtained by the present invention can be formed into a uniform shape resembling pentagonal or hexagonal shapes through high-order processing such as false twisting and crimp processing, or trilobal or T-shaped through irregular cross-section nozzles during spinning. % 4
Even if the shape is multi-lobed, 6-lobed, 8-lobed, etc., or has a variety of cross-sectional shapes, the key is to explain the synthetic leather l1. By using fibers that meet all the requirements, it is possible to obtain fiber pickles that maintain the good texture and good color development of the present invention.

EXAMPLES The present invention will be explained in detail below with reference to Examples, but the present invention is not limited thereto.

Examples 1 to 3 and Comparative Examples 1 to 2 Ethylene and vinyl acetate were radically polymerized at 60°C using methanol as a polymerization solvent, and the ethylene content was 44.
A molar random polymer was prepared using a caustic powder at 2° C. to make a saponified ethylene-vinyl acetate copolymer with a degree of saponification of 99 degrees or higher. After mourning, a large excess of the wet polymer was After repeating washing with pure water to which a small amount of acetic acid had been added, washing was repeated with a large excess of pure water to remove alkali metal ions such as Na and water from the polymer.

The alkaline earth metal ion content of Ca is approximately 10
ppm or less, and then, after separating water from the polymer using a dehydrator, further vacuum drying was carried out under sufficient pressure at 100°C or less. Intrinsic viscosity (W) = 1.05 cffl/f (
(Measured at 30° C. using 85% hydrated phenol as a solvent) was designated as Polymer A.

A polymer is extruded through an extruder, and the temperature of one die is 260℃.
The material was discharged from a nozzle under the following conditions and wound up at a spinning speed of 1000 cm/min. Thereafter, it was drawn in a conventional manner to obtain a multifilament of 24 filaments of 75 denier. The fiber forming process was good and there were no problems. A 1/1 plain woven fabric was obtained using the obtained 75-denier 24-filament multifilament as the warp and weft. Sodium hydroxide 1 f/11 and actinol FL-1oo 0 of this gray plain fabric
．． After de-sizing with a mixed solution containing 5f/R at 80°C for 30 minutes, add 20f/l of KO-benzaldehyde sulfonic acid! In a 20N sulfuric acid solution with a bath ratio of 50:1, the treatment times shown in Table 1 were varied and then sodium carbonate 5f/
The fabrics were treated in a solution of No. 1 at 80° C. for 30 minutes to replace sulfonic acid with sodium salt, thereby changing the binding amount (degree of acetalization) of sodium 0-benzaldehyde sulfonate. These fabrics were dyed with cationic dyes under the following conditions.

Dyeing conditions> Bath ratio 50:1 90°C
sl Ka-MunK style! ! 0 (7) Texture was evaluated using K/S value and saturation handling.

Examples 1 to 3 are polymers containing groups that can be ionized into anions in water within the range specified by the present invention. Comparative Example IFi is an example in which the anion does not contain an ionizable group, and Comparative Example 2 is an example in which the condition regarding the content of the anion ionizable group is not met.

Below are the margins, these conditions and results are number 111! Shown below. Examples 1 to 3 have cationic dyeability within the range that satisfies the content of the group that can be ionized by the anion as specified by Rujiki, and have a bright color tone with a large VS value and saturation. The texture is good and there are no problems in the processing process.

Examples 4 to 5 and Comparative Examples 3 to 4 Using chips of saponified ethylene vinyl acetate copolymers with a degree of saponification of over 99 and varying the ethylene content shown in Table 2 as A@polymer, each of the A polymers was The material was extruded using an extruder, the temperature of one die was 260° C., the material was extruded through a nozzle, the spinning speed was 1000 m/min, and a target pressure of 75 d2'/24 f was used to spin multifilament. The filaments that could be spun as multifilaments were used as warp and weft to weave tucks. This greige taffeta was subjected to the same conditions as in Example 1 with 'cs removed and 0-
9. Acetalization with sodium benzaldehyde sulfonate and evaluation as in Example 1.

Examples 4 and 5 These are examples of dyeing with cationic dyes in which the amount of ethylene copolymerized in FiA@polymer was within the range defined by the present invention described above.

Comparative Example 3.4 is an example in which the ethylene content was off, and the results are shown in Table 2.

In this example, the dyeability and dyeing density (K/S value) for cationic dyes after acetalization with sodium O-benzaldehyde sulfonate are shown.

The fibers had satisfactory texture, etc.

Examples 6 to 10, Comparative Examples 5 to 8 Examples of composite fibers are shown below. Examples 6 to 8 The same FiA polymer as that used in Example 1 was used, and the composite ratio of A polymer and B polymer was within the range specified by the present invention as described above. -10 are examples of cationic dye-dyeable composite fibers in which the ethylene copolymerization of the saponified ethylene-vinyl acetate copolymer IJ polymer used as the A polymer was carried out within the range specified in the present invention. As B polymer, [Ma] is 0.62#
The experiment was carried out using polyenalene terephthalate of /1 (measured using an Uebelohde type viscosity needle in a thermostat at 30° C. using a mixed solvent of equal amounts of phenol and tetrachloroethane as a solvent).

Polymer A and polymer B were melt-extruded using separate extruders, each weighed separately using a gear bong, and the cross-sectional shape was a perfect circle as shown in Figure 1, and the composite ratio was as shown in Table 3. The later denier is 75 dr/25 each.
Spinning and drawing was carried out to obtain f. Thereafter, the drawn yarns were used as warp and weft yarns to produce a plain woven fabric. Then Example 2
Acetalization using sodium O-benzaldehyde sulfonate and staining with a cationic dye were carried out in the same manner as above. In all of the examples, sacrificial products with excellent sharpness and dyeing density (K/S) and good texture were obtained.

Margin below No. 1 figure Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 4,

[Brief explanation of drawings]

1st~ Figure 7 shows a typical cross section of the composite fiber of the present invention. It's a side view. In the figure, A is the A polymer side, B is B poly Shows the mer side. license applicant Co., Ltd. nine La Re teenager Reason Man

Claims (1)

[Scope of Claims] 1. The basic skeleton is an ethylene-vinyl alcohol copolymer, the side chain of which is bonded with an atomic group having a group that can be electrolyzed into an anion in water, and the basic skeleton is an ethylene-vinyl alcohol copolymer. The amount of ethylene units in the water is 30 to 70 mol%, and the amount of groups that can be electrolyzed into anions in the water is 0.5 with respect to the total number of moles of ethylene units and vinyl alcohol units constituting the basic skeleton. A fiber made of a modified ethylene-vinyl alcohol copolymer having a content of ~30 mol%. 2. Consists of the copolymer according to claim 1 and another crystalline thermoplastic polymer, and the weight ratio thereof is 10:90 to 90:10.
A conjugate fiber characterized in that the copolymer is exposed on at least a portion of the surface of the conjugate fiber.