JP2593924B2 - Easy-dyed polyester drawn yarn and false twist yarn - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a drawn polyethylene terephthalate-based polyester yarn and a false twist yarn having easy dyeability under normal pressure.

(Prior art) Polyethylene terephthalate fiber (PET fiber) has excellent morphological stability and has become the mainstream regardless of synthetic nature, but it also has some disadvantages such as color development and moisture absorption. Some have been resolved as a result of research and development.

One of these is dyeability. PET fibers are almost impossible to dye at normal pressure.
Dyeing under pressure of about ° C is generally required.

On the other hand, a normal pressure dyeable yarn with a cationic dye using a 5-sulfoisophthalic acid metal salt or a derivative thereof as an improving agent is provided. However, this modification greatly deteriorates the fiber performance (for example, high elongation), and has been extremely unsatisfactory because expensive cationic dyes have to be used.

On the other hand, attempts have been made to dye at normal pressure with a disperse dye using an isophthalic acid-based modifier, but these are also inadequate. There is no present.

(Problems to be Solved by the Invention) The present invention aims to obtain a normal pressure dyeable polyester fiber which solves the above points.

(Means for Solving the Problems) At least 80 mol% of the constituent units are ethylene terephthalate residues, and the compound represented by the following general formula (1) is
~ 8 mol% copolymerization or spinning speed of polyester resin
It is a drawn yarn obtained by spinning at 1700 to 4000 m / min and then drawing and a false twisted yarn obtained by drawing false twist.

In the present invention, 80 mol%, more preferably 90 mol% or more of the constitutional unit is composed of an ethylene terephthalate residue, and 1 to 8 mol% of the compound represented by the formula (1) as a constitutional unit. Preferably, a polyester resin copolymerized with 2 to 6 mol% is used.

(1) The amount of the compound represented by the formula needs to be 1 mol% or more. If it is less than this, sufficient normal pressure easy dyeability cannot be obtained even if the present invention is carried out. The upper limit is 8 mol%,
Addition of more than this results in reduced dyeability, contrary to the generally known dyeing behavior due to modification, and also lowers fiber performance, resulting in so-called "heter" fibers. The most preferable dyeability is 2 to 5 mol%.

In order to obtain a drawn yarn or false twist yarn in the present invention,
In spinning the polyester resin, 1700-40
It is important that the spinning speed is 00 m / min. Even if the raw yarn obtained at a spinning speed of less than 1700 m / min is subjected to drawing, false twisting, heat treatment, etc., sufficient normal pressure easy dyeability cannot be obtained. The obtained spun yarn can be stretched and false-twisted if necessary. The false twist can be arbitrarily selected, such as a so-called indore method, an eye draw method, etc., and it is also possible to false twist by combining fibers with different spinning speeds, or by combining other fibers such as polyester and polyamide to obtain a structurally processed yarn. .

In the modifier specified by the formula (1), m and n are each 1 or 2, and preferably m = 1 and n = 1. Both R ₁ R ₂ are preferably methyl. of course
Those having m and n of 2 may be mixed. Also, those having m and n of 3 or more can be substantially mixed even if they are less than 10 mol%.

Further, regarding the modifier represented by the formula (1), the properties of the terminal are important. That is, in the modifier, phenolic properties
When unreacted impurities having an OH group are used in an amount exceeding 0.4 mol%, the synthesis (polymerization) of the polyester resin becomes unsatisfactory, and the obtained fibers are liable to be decomposed and deteriorated, resulting in undesirable ones. There was found. That is, in this case, even if it can be made into a normal pressure easy dyeing yarn, it does not endure practical use.

In obtaining the modified polyester resin of the present invention, the timing of addition of the modifier can be any time until the completion of the synthesis as a raw material for the synthesis of the polyester.
Among them, the most preferred is a method of adding before and after completion of esterification or transesterification.

Furthermore, the present inventors examined the relationship between the specific gravity of the false twisted yarn obtained by the present invention immediately after false twisting (unprocessed) and the dyeability, and found that the specific gravity is more preferably less than 1,370. I found it. Of course, even if it exceeds this, it is easy to dye under normal pressure, but the specific gravity is 1,370 from the dye utilization rate (dyeing rate).
Less than is preferred.

Further, as a result of examining the dynamic viscoelastic properties and dyeing properties of the false twisted yarn obtained by the present invention, it was found that a yarn satisfying the following formula (2) is preferable.

tan δ ₂ is the main decomposition peak intensity at 110 Hz from room temperature to 200 ° C. from the mechanical loss tangent, and T ₂ is the temperature that gives the main dispersion peak intensity. This indicates the ease of molecular motion, that is, the amount of the amorphous region, and it is preferable to have a larger tan δ ₂ at a lower temperature.

As described above, the present invention can be made into a normal pressure easily dyeable polyester fiber by using the specific modifier specified in the present invention. It is also possible to use an alkali metal salt of sulfoisophthalic acid and a derivative thereof in combination.

(Examples and Comparative Examples) Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. The polyester resins used in this example all use high-purity terephthalic acid (TPA) and ethylene glycol (EG) as the basic raw materials, and the polymerization catalyst is antimony trioxide (Sb
₂ O ₃ ) was synthesized by a conventional method (direct weight method) at 400 ppm. The modifier represented by the formula (1) was added to the TPA / EG slurry or added to the reaction system after completion of the esterification to synthesize.

(Measurement of intrinsic viscosity [η]) Measured at 30.0 ° C. with a phenol-tetrachloroethane = 1/1 (weight ratio) mixed solvent (Measurement of dynamic dispersion characteristics) 110 Hz, 3 with Rheovibron DDV-II-EP type ° C / min
Was measured at -150 ° C to 250 ° C under the following conditions.

Example-1 and Comparative Example-1 As a modifier, R ₁ and R _{2 in the} formula (1) are methyl groups, and the average n
Resin obtained by copolymerizing 4 mol% of {m} 1 and not containing m = 0 and / or n = 0 with polyethylene terephthalate (PET) ([η] = 0.681) (abbreviated as P-1) ) Was synthesized.

In addition, Regular Bright (containing TiO ₂ 0.08%) polyethylene terephthalate resin ([η] = 0.682) (R-1
Abbreviation) was synthesized.

1,300,1,700,3,000,4,000m / min each of these two resins
And a part thereof was drawn by a roller plate drawing machine so as to have a residual elongation of about 20 to 40% to obtain a drawn yarn.

A part of the yarn was false-twisted by an Indian low false twister to form a false twist yarn.

These yarns were used as a knitted fabric, and dyed at 98 ° C. (dye: Eastman Polyeseer Blue 3R-LSW 2% owf) and evaluated according to a conventional method. Table 1 shows the results.

Table 1 shows that the Regular PET resin (R-1) exhibited poor dyeing properties at normal pressure even when the spinning speed was changed.
Is good, but the spinning speed is 1700 even when P-1 is used.
It is clear that good dyeing properties cannot be obtained unless it is at least m / min. It is also clear that it is important that the specific gravity of the fiber after false twisting does not exceed 1.370.

It is also apparent that it is important for the dynamic dispersion characteristics to satisfy the conditions defined in the present invention.

Comparative Example-2 A compound defined by the formula (1) containing 0.5 mol% of an unreacted impurity having a phenolic OH group where n ≒ 1 m ≒ 1 but m or n is 0 It was used as a modifier, and adjusted so as to be copolymerized at 4 mol% to obtain a modified polyester resin.

However, the method of adding the modifier to the EG / TA slurry, the method of adding it to the reaction system after the esterification was completed, and the two methods were carried out. And not enough for fibers. It is also shown that the dynamic dispersion characteristic is preferably T ₂ <125 ° C. tan δ ₂ ≧ 0.20.

Example-4 When R ₁ and R _{2 in the} formula (1) are hydrogen, m ≒ 1 n ≒ 1, and m =
A modified PET resin obtained by copolymerizing 5 mol% of a modifier having 0.1 mol% of impurities with 0 and n = 0 being spun at a spinning speed of 2,500 m / min;
Subsequently, the film was stretched by a roller plate stretching machine. The stretched yarn was evaluated for dyeing in the same manner as in Example 1, and showed good normal-pressure dyeability.

Claims (2)

(57) [Claims] 1. A polyester resin obtained by copolymerizing 1 to 8 mol% of a compound represented by the following general formula (1), wherein at least 80 mol% of the constituent units are ethylene phthalate residues, and a spinning speed of 1700 to 4000 m / A drawn yarn spun in minutes and then drawn. (R1 and R2 are hydrogen or methyl groups, m and n are 1 or 2) 2. A polyester resin obtained by copolymerizing 1 to 8 mol% of a compound represented by the following general formula (1), wherein at least 80 mol% of the constituent units are ethylene terephthalate residues.
A false twisted yarn obtained by spinning at a spinning speed of 1700 to 4000 m / min and then draw false twisting and having a specific gravity of less than 1.370. (R1 and R2 are hydrogen or methyl groups, m and n are 1 or 2)