JPS5930912A - Easily dyeable conjugate fiber - Google Patents

Abstract

PURPOSE:The titled composite conjugate fibers, containing a polyester having ethylene terephthalate units and ethylene-5-sodium sulfoisophthalate units, etc. as a sheath component and a polymer having the affinity for the polyester as a core component, and having a high strength and general-purpose properties. CONSTITUTION:Easily dyeable conjugate synthetic fibers, containing a polyester having 1.85mol% ethylene terephthalate units and 3-6mol% ethylene-5-sodium sulfoisophthalate units as a sheath component and a polymer, e.g. nylon 6, having the affinity for the copolyester and good fiber-forming properties as a core component, and prepared by melt extruding the components through a nozzle to form conjugate fibers, drawing the resultant conjugate fibers while heat-treating the fibers with a plate heater, etc., and winding the heat-treated fibers. The sheath and core components are coaxially conjugated. The ratio of the core component is preferably 10-50wt%.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to easily dyeable conjugate fibers, particularly pressure dyeable conjugate fibers.

Conventionally, polyester fibers mainly made of polyethylene terephthalate have developed greatly due to their useful properties and cost advantages, and have become one of the main products of synthetic fibers.

However, in terms of dyeability, it is significantly disadvantageous compared to other synthetic fibers, especially nylon and acrylic, and the current situation has been to use high-pressure dyeing methods. Of course, atmospheric pressure dyeing is also possible using carrier dyeing methods and various copolymerized polyesters, but the former has the problem of deep color dyeing and pollution of the carrier material, and the latter reduces the useful properties of polyester and increases the cost. Currently, sufficient conditions are not provided for practical use due to problems such as high cost. but.

So-called cationic dye-dyeable polyesters, which are copolymerized polyesters with sulfonate groups introduced therein, are supplied to the market today as one of the few industrially successful polyester fibers.

However, the typical copolymerization component ethylene-
When 5-sodium sulfoisophthalate is copolymerized with the ethylene terephthalate component, the melt viscosity increases significantly during polymerization, which increases the degree of polymerization.
It has been industrially practiced to suppress the copolymerization ratio to at most 3%/L'%. Therefore, the strength of spun fibers is lower than that of ordinary polyethylene terephthalate.
In particular, in the case of fitment, the strength level is further reduced due to high-level processing such as false twisting, which remains a practical problem, and the dyeability is still low, and it cannot be said to be dyeable under normal pressure. there were. In particular, in order to impart dyeability under normal pressure, ethylene-5-sodium sulfoisophthalate should be added to
Although it is necessary to copolymerize more than mol %, the degree of polymerization must be relatively lowered, which is even more disadvantageous in terms of strength, and only products with poor practicality can be obtained.

In view of the above-mentioned current situation, the present inventor discovered that the problem could be solved by forming composite fibers, leading to the present invention.

That is, in the present invention, 85 moA/96 or more is an ethylene terephthalate unit and %'1. 3-6-1:/I/96
An easily dyeable composite fiber in which a polyester having noethylene-5-sodium sulfoisophthalate units is used as a sheath component, a polymer having good fiber-forming properties that has an affinity with the sheath component is used as a core component, and both are concentrically combined. This is a summary.

Here, it is necessary to contain 857 μ% or more of ethylene terephthalate units because we want to preserve the thermally stable ring and favorable properties of polyethylene terephthalate. In addition to containing 6 mol%, small amounts of acid components such as isophthalic acid, pyromellitic acid, adipic acid, r-oxybenzoic acid, propylene glyco-p, neopentyl glyco-/L/, 1.4-butanedio-p , aμcols such as pentaerythritol may be included.

In addition, the content of ethylene-5-sodium sulfoisophthalate is 3 mol% or more, preferably 6.5 mo/I/96 or more, but even if it is 6 mo/I/96 or more, the ink dyeing effect remains the same. 3 to 6 mo/I/96 is appropriate, and 4 to 5
Mol% is the most preferred embodiment.

Next, in the conjugate fiber of the present invention, the core component serves as a reinforcement, and must have an affinity with the sheath component and have good fiber forming properties. Specific examples of polymers forming the core component include nylon 6,
Examples include polyamides such as nylon 66 or copolymers containing these as main components, and polyesters such as polyethylene terephthalate and polybutylene terephthalate. Polyamides are preferred because they facilitate the production of high-strength fibers.

The composite fiber of the present invention is different from the crimpable composite fiber described in Japanese Patent Publication No. 45-28728, etc., and is intended to be a versatile fiber that does not have 11 crimpability.
It is necessary that the sheath component and the core component are combined concentrically. There is no problem even if there is a plurality of cores, but a single core is preferred because it is easy to manufacture.

The composite ratio is determined by taking into account stainability and intensity.

The strength increases as the ratio of the core component increases, but in order to obtain easily dyeable fibers, the ratio of the sheath component must exceed a certain level, and the sheath component accounts for 20% by weight or more, preferably 25% by weight or more. This is desirable. In addition, when using polyamide as a core component, if the proportion is too large, the stiffness and texture of polyester will be impaired, so it is desirable to keep it at 50% by weight or less, and 10 to 50% by weight, especially 15% by weight.
~50% by weight is suitable.

The cross-sectional shape of the composite fiber is not limited to a circular shape, and may have an irregular cross-section such as a trilobal shape or a hexalobular shape. Further, in the composite fiber of the present invention, at least one of the sheath component and the core component contains an antistatic agent.
It may also contain flame retardants, pigments, etc. Furthermore, the composite fiber of the present invention can be used not only as a filament yarn but also as a staple.

EXAMPLES Hereinafter, one embodiment of the present invention will be specifically explained with reference to Examples.

Example ethylene terephthalate unit (TP) and ethylene-5''
A copolyester having 'sodium sulfate units (SIP) at a ratio of M/I/96 shown in Table 1 was synthesized according to a conventional method, and the obtained copolyester was formed into chips and dried to obtain component A. .

On the other hand, as component B, nylon 6 chips (having an intrinsic viscosity [η) of −1.1 as measured with sulfuric acid] were prepared.

Using component A as a sheath component and component B as a core component, changing the composite ratio and using a 36-hole nozzle at a spinning temperature of 270°C,
A concentric core-sheath type composite yarn was spun at a spinning speed of 1200 m/min, and the discharge rate was adjusted to match the fineness of 75 denier after drawing. Stretching was carried out at 130°C using a hot roller at 85°C.
Stretched while heat-treated with a flat plate heater at ℃, and stretched at a speed of 700 f.
I went at fi/min.

Table 1 shows the strength and elongation of the obtained composite yarn, dyeability, and strong change of the false twisted yarn. In addition, the stainability was determined using ASTRAZO.
N BLUlil: A tube-knitted sample with 5% owf of F'RR (basic dye manufactured by BASF') was heated at 98°C.
After dyeing for 1 hour, start with the darkest color ◎
.

The yarns were indicated as ○, Δ, and ×, and were judged as ○, which were normally recognized as normal pressure dyeable yarns in the market.

In addition, the solution relative viscosity ηr of copolyester p is pheno-y
v/0.5 t/1oo in 1/1 mixed solvent of ethane tetrachloride
m/, measured at a temperature of 25c.

In addition, the false twisting process was performed using a 5T-6 plate twisting machine manufactured by San-Ai Heavy Industries Co., Ltd., at a first heater temperature of 165°C and an overfeed rate of 5.
．． 1%, false twist number 3042 T/M, yarn speed 981V'
I went at min.

In Table 1, &1 to 5 are comparative examples.

Table 1 65

Claims (1)

[Claims] 1.85 mol% or more of ethylene terephthalate units, the sheath component is polyester having 3 to 6 mo/I'% of ethylene-5-sodium sulfoinphthalate units, and has good fiber forming properties that have affinity with the sheath component. An easily dyeable composite fiber in which a core component is a polymer and both components are concentrically composited. 2. The composite fiber according to claim 1, wherein the core component is polyamide. 6. The composite fiber according to claim 2, wherein the proportion of the core component is 10 to 50% by weight.