JPS61167014A - Production of blend-colored acrylic fiber of high strength - Google Patents

Abstract

PURPOSE:A spinning dope composed of a specific acrylonitrile polymer solution and coloring pigments is made into fibers through the dry-wet process, drawn, washed and subjected to secondary drawing to obtain the titled fiber with dyeing fastness, color developing and brightness. CONSTITUTION:A solution of an acrylonitrile polymer which contains (A) more than 85mol% of acrylonitrile and (B) about 25mol% of monomers copolymerizable with acrylonitrile and has more than 2.5 intrinsic viscosity is mixed with coloring pigments thoroughly. Then, the mixture is filtered through a filter with a sieve opening of less than 5mu to prepare a spinning dope. The dope is extruded through spinning nozzles into air or inert gas atmosphere. The extruded fibers are introduced into the coagulation bath to form the yarn, the yarn is drawn and washed, then subjected to secondary drawing so that the total draw ratio exceeds 10 based on the coagulated yarn to give the objective fiber.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention has significantly higher mechanical properties than conventionally commercially available acrylic fibers for clothing, and in particular has a tensile strength of at least 10 g/min. The present invention relates to a method for producing a spruce-dyed acrylic fiber that has a high strength of d or more and has excellent dyeing properties such as color fastness.

[Conventional technology]

Traditionally, acrylic fibers have excellent properties such as dye clarity, light resistance, and bulkiness that are not found in other general-purpose clothing fibers such as polyamide and polyester fibers, so they are used for clothing and interior decoration such as car vents and curtains. Widely used (manufactured and sold).

However, this acrylic fiber has a lower mechanical strength, particularly a lower tensile strength, than the other general-purpose fibers mentioned above, which limits its use and at the same time, there has been a strong desire to improve this mechanical strength.

Recently, as the polymer constituting the acrylic fiber, a polymer whose degree of polymerization is significantly higher than that of the polymer constituting the conventional acrylic fiber has been used to significantly improve the mechanical strength of the acrylic fiber. Attempts have been proposed (for example, Japanese Patent Laid-Open No. 199809/1983).

However, such high-strength acrylic fibers have highly oriented polymer chains in their fiber structure and are extremely dense, so it is difficult to dye them using normal dyeing methods. If dyeing is attempted, there is a problem in that the high degree of orientation of the polymer chains is lost, and as a result, the characteristic strength thereof is reduced.

[Problem that the invention seeks to solve]

An object of the present invention is to provide a source-dyed acrylic fiber that solves the problem of dyeability, which is a problem of the above-mentioned high-strength acrylic fiber, and another object of the present invention is to provide a source-dyed acrylic fiber that solves the problem of dyeability, which is a problem of the above-mentioned high-strength acrylic fiber. We are trying to provide a manufacturing method for this.

[Means for solving problems]

The object of the present invention is to achieve the invention described in the claims, that is, at least a comonomer comprising about 85 mol% or more of acrylonitrile and about 25 mol% or less of a comonomer copolymerizable with the acrylonitrile. 2.5
A. Coloring pigments are added to the acrylonitrile polymer solution having an intrinsic viscosity of The spinning dope is once discharged into air or an inert atmosphere through a spinneret hole, and then introduced into a coagulation bath to complete coagulation to form fiber threads by dry/wet spinning methods, followed by drawing, washing, etc. This can be achieved by performing secondary stretching such that the total stretching ratio per coagulated fiber thread is at least 10 times after the above treatment.

The acrylonitrile (hereinafter abbreviated as AN) polymer used in the present invention has at least about 85% mole of AN, preferably about 97% or more, more preferably 99% or more, and about 15% or less, preferably is about 3 mol% or less, more preferably 1 mol% or less of a comonomer copolymerizable with the AN, such as acrylic acid, methacrylic acid, itaconic acid, and their lower alkyl esters, vinyl acetate, methacrylic acid, etc. Amide, acrylamide, vinyl chloride, vinylidene chloride, vinylsulfonic acid, p-styrenesulfonic acid, 2-acrylamide-2
- AN-based polymers obtained by copolymerizing at least one or two or more of methylpropanesulfonic acid, allylsulfonic acid, methallylsulfonic acid, and metal salts thereof can be exemplified.

In the present invention, acidic group-containing comonomers such as vinyl sulfonic acid, p-styrene sulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, allyl sulfonic acid, methallyl sulfonic acid, and metal salts thereof are particularly preferred.
．． The copolymer copolymerized in a range of 05 to 0.5 mol% is
This is desirable for producing high-strength original acrylic fibers, which is the object of the present invention.

Further, the molecular weight of the AN-based polymer is preferably at least 2.5, preferably 2.6 to 6.01, and more preferably 2.8 to 3.6, expressed as intrinsic viscosity. That is, if the intrinsic viscosity is less than 2.5, the high-strength fiber targeted by the present invention cannot be obtained, and on the other hand, if the intrinsic viscosity is too large, it becomes difficult to prepare a spinning dope with good spinnability. For example, if the intrinsic viscosity exceeds 6.0, the viscosity of the spinning dope increases rapidly and the spinnability decreases significantly, and if the polymer concentration of the spinning dope is lowered to avoid this, fiber forming properties also decrease. However, devitrification or porous fibers are likely to be formed (this is not preferable).

Such AN-based polymers are dimethyl sulfoxide (D
MSO), perisotylformamide (DMF), dimethylacetamide (DMAc), ethylenecahebonate, and other organic solvents, zinc chloride, rhodan salt, nitric acid, and other inorganic solvents, or a mixed solvent thereof. The polymer solution used in the spinning dope is used as a spinning dope, and the polymer concentration of this spinning dope is in the range of about 5 to 20% by weight, preferably about 10 to 18% by weight.

Various known coloring pigments, dyes, etc. are added to and mixed with the spinning dope thus obtained. The amount of the color pigment added is preferably in the range of o, oos to 5% by weight, preferably 0.1 to 2.0% by weight, based on the weight of the polymer.

Pigments and dyes are not particularly limited, but examples of pigments include carbon blanks, phthalocyanine pigments, insoluble azo pigments,
Titanium dioxide etc. can be used.

In addition, the dye is a commercially available cationic dye used for dyeing acrylonitrile-based dried fibers,
You only need to choose one with relatively high color fastness, and a representative example of each color is Strazon Yellow 7GLL.
(Manufactured by Bayer), Basacryl Red GL (Manufactured by Particier Aniline), Strazon Blue PGL (Manufactured by Bayer), Diacrylic Plub Brilliant Green 2G (Manufactured by Ciba), Cepron Brown YL (Manufactured by DuPont) and cation black SH (manufactured by Hodogaya Chikaragata Co., Ltd.)
etc.

Next, colored pigments or dyes are added and mixed into the spinning stock solution,
Filtering is carried out using a filter medium with an opening of 5 microns (μ) or less, preferably 3 μ or less, specifically a sintered filter or the like. This filtration is not only directly related to the spinnability of the spinning dope in dry/wet spinning described below, but also affects the drawability of the resulting undrawn coagulated fiber yarn as well as the secondary drawability under dry heat. However, only by filtering using the above-mentioned filter medium with a diameter of 5μ or less, the excellent drawability of the fiber yarn obtained by dry/wet spinning described later can be stably and favorably increased by more than 10 times. Magnification stretching can be performed.

In order to form the fiber yarn of the present invention using the above spinning dope, the spinning dope is once discharged into air or an inert atmosphere such as nitrogen, helium, argon, etc. through the spinneret hole, and the discharged yarn is It is necessary to form fiber threads by introducing the spinning solution into a coagulation bath containing a coagulant and coagulating it, that is, by applying a dry/wet spinning method.

In other words, in order to form a high-strength fiber thread from the highly polymerized AN-based polymer having the above-mentioned intrinsic viscosity, the selection of the spinning method is important, and even if dry spinning or wet spinning methods are used, However, there is a problem in that the mechanical strength is only at a low level, and it is difficult to suppress the occurrence of fusion between single filaments, making it virtually impossible to manufacture multifilaments.

The distance between the spinneret surface and the coagulation bath liquid level in dry/wet spinning is set within a range of approximately 1 to 20 m, preferably 2 to Low, and the spinning draft is set within a range of 0.1 to 1.5, preferably 0. It is preferable to set it within the range of 2 to 0.8.

The thus spun coagulated yarn is primarily stretched approximately 2 to 10 times, preferably 4 to 8 times, after or before washing with water,
The obtained fiber yarn in a water-swollen state before drying and densification is immersed in a dye bath containing a cationic dye, and the dye is adsorbed into the fiber.

The fiber yarn thus obtained is then heated to about 100-170°C.
It is heated to a temperature of , and is dried and densified.

The dried and densified fiber thread is stretched under a drawing tension of about 1 g/d or more, preferably 1.5 to 2.0 g/d.
Secondary drawing is carried out in heated air at 0 to 250° C. so that the effective total drawing ratio is at least 10 times, preferably 12 times or more, per the original length of the coagulated fiber yarn. This dry heat stretching means is not particularly limited, and includes, for example, a hot plate,
Although there is dry heat stretching using hot rolls, hot tubes, etc., it is preferable to use a tubular heating tube capable of supplying and discharging heated air. Also,
This dry heat secondary stretching may be carried out together with drying and densification, that is, drying and densification may be carried out at the same time as the wet fiber yarn is stretched during the dry heat secondary stretching.

The thus obtained acrylic fiber yarn of the present invention is a dyed fiber yarn that not only has outstanding mechanical strength but also excellent color development, fastness, and vividness, and is suitable for use in clothing and interior decoration. Of course, it can be used for many industrial and other uses.

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

Example 1. Comparative Examples 1 to 4 Acrylonitrile (AN) 99.8 mol% and 2-acrylamido-2-methylpropanesulfonic acid (AMPS)
An AN copolymer having an intrinsic viscosity of 3.2 was prepared by dissolving 0.2 mol% in DMSO and performing solution polymerization.

Add 5 g/l of cationic dye Maxilon Blue or black pigment (Microlith Black BN) to the resulting copolymer solution.
After uniformly dispersing the solution (manufactured by Ciba Corporation) at a concentration of 4%, this solution was filtered using a sintered metal filter with a mesh opening of 3 and 10 μm as a filter medium, and then a colored spinning stock solution with a polymer concentration of 16% was filtered. Prepared. These spinning stock solutions were heated to 80 degrees and subjected to dry and wet spinning, respectively. The distance between the spinneret and the coagulation solution surface was set to 51), and the coagulation bath was 1
A 55% DMSO aqueous solution at 5°C was used.

The obtained coagulated thread was stretched 5 times in hot water, washed with water,
Table 1 shows the fibers of the yarn obtained by strain drying at 20°C, and then dry heat secondary stretching at 190°C using a hot plate, and stretching at a maximum stretching ratio of 80%. did. When the opening was 3 μm, all the fibers had good spinnability and high strength, and were found to be dyed high-strength fibers that are useful for practical use.

*A filter material with a mesh opening of 3 μm means that when air is filtered,
A filter medium that removes 95% or more of dust with a particle size of μm or more.

Comparative examples will be described to further clarify the effects of the present invention. Everything is the same as in the example except that the dyeing is carried out after dry heat stretching. AMPS of 0.2 mol% has sufficient tensile strength, but the dyeability is poor (Comparative Example 3). When 1.2 mol % of AMPS is copolymerized to improve the dyeability, the dyeability is sufficient, but the tensile strength is significantly lowered and the targeted high-strength fiber cannot be obtained (Comparative Example 4).

(Margins below the wooden page)

Claims (4)

[Claims] (1) A coloring pigment is added to an acrylonitrile polymer solution having an intrinsic viscosity of at least 2.5 and consisting of about 85 mol% or more of acrylonitrile and about 25 mol% or less of a comonomer copolymerizable with the acrylonitrile. After mixing thoroughly, this solution is filtered through a filter medium with an opening of 5 microns or less, and the resulting filtrated solution is used as a spinning stock solution. A fiber thread is formed by a dry/wet spinning method in which the fiber is discharged into a coagulating bath and then introduced into a coagulation bath to complete coagulation, and after being subjected to treatments such as drawing and washing, the total drawing ratio per coagulated fiber thread is A method for producing high-strength spun-dyed acrylic fibers, which comprises performing secondary stretching so that the fibers are stretched at least 10 times. (2) In Claim 1, the acrylonitrile polymer contains about 97 mol% acrylonitrile and about 0.97 mol% acrylonitrile.
A method for producing a high-strength spun-dyed acrylic fiber which is a copolymer containing 05 to 0.5 mol% of an acidic group-containing comonomer as an essential component. (3) In claims 1 and 2, the acrylic fiber yarn is stretched at least 12 times at a total stretching ratio, and has a tensile strength of about 10 g/d or more and a tensile strength of 4.5 g/d or more.
A method for producing a high-strength spun-dyed acrylic fiber, which is a fiber yarn that exhibits a hanging strength of g/d or more. (4) In claims 1 to 3, the secondary stretching is stretching under dry heat, and the dry heat stretching makes the total stretching ratio 13 times or more. A method for producing dyed acrylic fibers.