JPS60209068A - Light fastness modification of aromatic polyamide fiber - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for dramatically improving the light resistance of aromatic polyamide fibers. This particularly relates to the field of clothing that requires light resistance.

Prior Art Fully aromatic polyamides are known to be suitable for a wide range of applications. Aliphatic polyamides (e.g. nylon)
It has a higher softening point and melting point than Nylon 6.6, etc.), and has superior strength retention at high temperatures, shape stability, heat resistance such as thermal decomposition, flame resistance, and flame retardance. Without,
Heat resistant, flame retardant, flame retardant fibers, high strength high Young's modulus fibers, with extremely desirable physical and chemical properties such as chemical resistance, electrical properties, and even mechanical properties such as strength and Young's modulus. Suitable for applications such as film molding materials. For example, it is widely accepted for use as an electrical insulating material in motors, transformers, etc., in industrial applications such as filter bags, heating tubes, and other textile applications where aesthetic elements are not required. On the other hand, in textile textiles where fashionable colors are considered important, aviation suits,
Used for firefighting uniforms, etc. Sportswear that can be worn even under heavy duty conditions by blending and knitting rayon, cotton, wool, etc., and adding functions such as sweat absorption, moisture absorption, and heat retention to the high functionality of aromatic polyamide. , and plans are being made to expand into the field of comfortable clothing. As mentioned above, in the busy development of the clothing field, light resistance has traditionally been a major barrier.

OBJECTS OF THE INVENTION The object of the present invention is to obtain a fabric having excellent light fastness while retaining as much as possible the excellent properties of aromatic polyamide fibers.

Conventionally, in order to improve the light resistance of aromatic polyamide fibers, there is a method of mixing ultraviolet absorbers during dyeing, but since this fiber is inherently difficult to dye, the diffusivity of the ultraviolet absorbent within the fibers is low and the results are satisfactory. I haven't been able to get it. Further, even if a carrier is used as an adsorption promoter, the ultraviolet absorber is not sufficiently introduced into the fiber, and no effect of improving light resistance is observed.

In view of the current situation, the present inventors have studied a method for improving the light resistance of aromatic polyamide fibers more effectively than conventional methods, and have arrived at the present invention.

Constitution of the Invention φ That is, the present invention is "a method for improving the light resistance of aromatic polyamide fibers, which is characterized by heat-treating aromatic polyamide fibers containing an ultraviolet absorber in the coexistence of urea and thiourea."

In the present invention, compounds represented by the following general formula can be used as the ultraviolet absorber.

(1) Phenylbenzotriazole or (2) 212/dithodibenzophene These compounds not only have an affinity for aromatic polyamide polymers and have good blendability, but also have a wavelength of 34
It has a characteristic of having a large absorption capacity for light in the range of 0 to 410 mμ, and examples thereof include the following.

2- (2'-hydroxy-51-methylphenyl)benzotriazole 2 (2/-hydroxy-3'-chloro-5'-methylphenyl)benzotriazole, 2
-(2'-hytoroxy3'-chlor-s'-t-'7
'tylphenyl)hencytrizole, 2,2'-dihydroxy-4゜4'-dimethoxybenzophenone 2
, 2/-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4' dibenzyloxybenzophenone, and the like. Among these, 2 (2/-hydroxy-5'-methylphenyl)benzotriazole and 2,2/-dihyF-roxy4,4'
-dimethoxypenzophenone is particularly preferred.

The ultraviolet absorber may be added in the aromatic polyamide fiber during the polymerization step of the aromatic polyamide, or may be added in an aromatic polymer solution (polymer dope). The amount of the ultraviolet absorber added is 1 to 15% by weight based on the aromatic polyamide, and particularly preferably 3 to 1% by weight.
It is 2% by weight. Ultraviolet absorber is 1 layer fc% ILA
In the case of towns, almost no light resistance improvement effect was observed, and
If 15% by weight is added, the flame retardant properties will decrease.

The aromatic polyamide fiber used in the present invention consists of repeating units represented by the general formula %. In the above general formula, a, RIG 1 may be the same or different,
It is selected from a hydrogen atom and a furkyl group having 5 or less carbon atoms. As the furkyl group having 5 or less carbon atoms, methyl group, ethyl group,
Examples include a bupyl group, a butyl group, a pentyl group, etc., but a hydrogen atom is preferred.

Further, Ar and lArc e Arc may be the same or different, and are selected from the general formula % formula % (5).

General formula (1) + (2) K O-, Te, -X- & House-
It is a group selected from o-, -8-*N-1. -X- is preferably selected from -〇-91, and more preferably -Ko. General formula) e (4) ic 1-1te-Y-C1'b
Un and others are selected. (R represents a furkyl group having 5 or less carbon atoms as described above.) -Y- is preferably -0-. General formula (1) ) (2) I (5) K 1:
Ar and Ar' may be the same or different and are selected from coaxially oriented aromatic rings. Coaxially or parallelly oriented aromatic rings include, for example, 1,4-phenylene group, 1,3-
Examples include phenylene group, 4.4'-biphenylene group, 1,5-s7tyrene group, 2.6-naphthylene group, 2.5-pyridylene group, etc., but preferably 1.4-
A phenylene group and a 1,3-phenylene group are selected.

Examples of preferable aromatic polyamides used in the present invention include -Nm K<XNu-...25molti, 0shaco-
°-°s o -v polyamide, -c o +CO-...30molty co <ward huge possible:)-Nu-...40 mo
Polyamide consisting of moles, -co %≠)) Co -... Polyamide consisting of 50 moles, -NHshaNt... 25 moles CO+C
O-...Polyamide consisting of 50 molti, -coba! Σco -...Polyamide consisting of 50 molti, -cobeφΣCO-...Polyamide consisting of 50 molti, ym((minister))N)i -... 30 molti Examples include poly7mi-do.

In addition, the benzene ring in the skeleton (υ~(5)) and the above-mentioned aromatic ring residues include, for example, /S rogone group (for example, chlorine, bromine, fluorine), lower alkyl group (methyl, ethyl, inglovir, etc.).

n-propyl group), lower alkoxy group (methoxy, etoyacyl group), cyano group, 7-cetyl group.

O may be included as a substituent such as a nido group. Here, a method for applying a mixture of urea and thiourea to an aromatic polyamide fiber containing an ultraviolet absorber will be described in detail below.

In the present invention, the light fastness improving KI [no significant effect is observed only when urea and thiourea are present together; no significant effect is observed when treated with urea or thiourea alone. For example, when applying a mixture of urea and thiourea to an aromatic polyamide fabric containing an ultraviolet absorber, it is effective whether it is applied in the form of powder or solution; After patting, it is wrung out with a mangle or applied to the fabric by spraying, and then dried.

When applied in solution, the concentration of the urea and thiourea mixture can range from 1 to 100% by weight, but is particularly preferably from 20 to 80% by weight. Also, the mixing ratio (weight ratio) of urea and thiourea is 8G:20 to 20:8.
It is effective in the range of 0, but a particularly remarkable effect is observed in the range of 70:30 to s o , : s .

This is the case when the ratio of The pH of the solution may be within the range of 3 to 1G. The drying temperature may be within the range of 80 to 130°C. Next, heat treatment (curing) is performed, and the curing conditions are as follows: temperature is 160 to 210°C, and treatment time is 3.0 seconds to 5 minutes. Particularly preferred: 180-190
°C, for 1 to j minutes. Under milder conditions, the effect of improving light resistance is small, and under harsher conditions, the aromatic polyamide fibers turn brown.
It has a hard texture and cannot be put to practical use.

The aromatic polyamide of the present invention may be dyed. Furthermore, the effects of the present invention are particularly great when an aromatic polyamide with improved dyeability is used as the third component. This is thought to be because the inactivation reaction of the amide 7 group is effectively carried out inside the fiber.

Furthermore, the aromatic polyamide fibers targeted by the present invention may be undyed (fibers after scouring and setting), or dyed with ionic dyes such as acid dyes and cationic dyes, or nonionic dyes such as disperse dyes and threne dyes. It may be something that has been done.

Furthermore, it may contain colored pigments. Furthermore, the present invention applies not only to aromatic polyamide fibers alone, but also to other synthetic fibers (fibers made of polyester, aliphatic polyamide, vinyl chloride, etc.), natural fibers, semi-synthetic fibers (cotton, rayon, etc.).

It can also be applied to things.

Effects of the Invention By heat-treating the aromatic boria SV fiber containing an ultraviolet absorber in the coexistence of urea and thiourea, the light resistance is significantly improved compared to when the fiber does not contain an ultraviolet absorber.
At the same time, the decrease in strength due to light irradiation is reduced (strength retention rate is improved).

Example Hereinafter, the present invention will be specifically explained with reference to Examples.

Example 1. Comparative Examples 1-2 Polymetaphenylene inphthal 7! Tinuvin 326 (ultraviolet absorber, Ciba Geigy product) for 5 minutes
Weight-containing 40-count twin yarn polymetaphenylene isophthal 7 medium short fiber (Funex ■, Teijin ■ product)
padded in an aqueous solution with a concentration of 30% by weight, which is prepared by mixing urea and thiourea in a weight ratio of 60:40 and dissolving it in water.
I narrowed it down to a big 7 hit rate of 80% in Mangle. Then, after drying at a temperature of 200°C for 4 minutes, curing was performed at 180°C for 1 minute. The light resistance of the resulting treatment system was measured and was found to be grade 4.5. A similar test using polymetaphenylene isophthal 7-mid short fibers containing no Tinuvin 326 resulted in a grade of 3.5.

(Comparative Example 1) Light resistance is determined using a fade meter, with no fading at all after 40 hours of irradiation (jl good) being grade 5, and extremely severe fading (minimum length) being grade 1. It was classified and judged.

The strength and elongation before and after the light resistance measurement (before and after 40 hours of light irradiation) were measured using a Tensilon. As a comparative example, the strength and elongation were measured when 6 batches were blown using water instead of a mixed aqueous solution of urea and thiourea, and the results are shown in Table 1.

Examples 2-7. Comparative Examples 3 to 5 Polymethaneenylene isophthalic 7-mid fiber containing Tinubicene 326 in the polymer (Cornetx [F]; Teijin (Taru Products)) plain woven fabric (aO count double yarn spun yarn).

Padded with a solution in which urea and thiourea were mixed in the weight ratio shown in Table 2 and dissolved in water at a concentration of 30% by weight, the area weight zoo#/s/) was mixed with a mangle to give a Bic7 weight ratio of 80.
After squeezing the mixture, it was dried at a temperature of 100°C for 4 minutes. Then, it was cured at 190°C for 1 minute. The light resistance of the obtained treated fabric was measured and shown in Table 2.

As Comparative Examples 3 to 5, Table 2 shows 100% water (Comparative Example 3), urea alone (Comparative Example 4), and thiourea alone (Comparative Example 5).

Table 2 Example 8 and Comparative Example 6 (m/n=6 o/s o ) Expressed in repeating unit, fineness 1500d/1000
Tinuvin ■326 with physical properties of fil I strength 2agr/ass, elongation 4.5cm, and initial Young's modulus aooogr/d・
Two aromatic pov (314'-diphenyl ether terephthalamide) copolymer fibers containing 5% by weight of ply (1500/2) were twisted into 8 twists of LIOT/10CII. The combined twisted yarn was padded in a 30% concentrated aqueous solution prepared by dissolving a mixture of 60 parts of urea and 40 parts of thiourea in water, and squeezed with a mangle to a pick-up rate of 80 cm.
It was dried at 00°C for 4 minutes. Then, it was cured at 190°C for 1 minute. The light resistance of the obtained treated fabric was measured and shown in Table 3.
It was shown to. In addition, as a comparative example, water xoo% (Comparative Example 6)
The cases are also shown in Table 3.

Table 3 that's all

Claims (1)

[Claims] A method for improving the light resistance of aromatic polyacid fibers, which comprises heat-treating aromatic polyamide fibers containing an ultraviolet absorber in the coexistence of urea and thiourea.