JPH05222316A - Thermally stable crystal modification and method for dyeing therewith - Google Patents

Abstract

PURPOSE:To overcome troubles such as nonuniform dyeing due to a poor thermal stability of a dye by dyeing a hydrophobic fiber with a specific crystal modification (a beta-crystal) of a specific dye. CONSTITUTION:A hydrophobic fiber is dyed with a crystal modification (a beta-crystal) of a dye which is represented by the formula and gives an X-ray diffraction pattern having a strong peak at a diffraction angle [ deg.] of 25.4 and fairly strong peaks at diffraction angles (2theta)[ deg.] of 10.5, 15.7, 18.6, 23.0, 23.5, and 23.8 in a powder X-ray diffraction with Cu-Kalpha radiation. A beta-crystal is excellent in dyeing stability at a high temp. and enables uniform dyeing. The beta-crystal of the above dye is prepd. by heating a wet or dry cake of an a- crystal, which is obtd. by diazotization and coupling by a well-known method, usually to 40 deg.C or higher in water, a water-sol. solvent, or water contg. an anionic or nonionic surfactant.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a crystal modification of a heat-stable dye and a dyeing method using the same.

[0002]

2. Description of the Related Art Equation (1) The dye represented by is known from JP-B-52-34649. This dye is known to dye synthetic fibers such as polyethylene terephthalate fiber in red. In the dyeing industry in recent years, the ratio of dyeing methods has been streamlined and energy-saving measures have been advanced to reduce the bath ratio and at the same time, the dyeing solution is circulated by stopping the dyeing object such as over-Meyer dyeing, cheese dyeing, beam dyeing and jet dyeing. However, dyes having excellent dispersion stability at high temperatures are strongly desired in order to prevent dyeing due to the filter effect.

[0003]

When the dye represented by the formula (1) produced by the usual method is used for dyeing at high temperature, the dispersion state of the dye particles in the dyeing bath is lowered, and therefore, the dye particles are uniformly dispersed. There is a drawback that a dyed product having a high dyeing density cannot be obtained.

The present inventors have completed the present invention as a result of intensive studies to solve the above-mentioned problems. That is, the present invention provides (1) a strong peak at a diffraction angle [°] 25.4 in a powder X-ray diffraction method using Cu-Kα rays, and a diffraction angle (2θ) [°].
10.5, 15.7, 18.6, 23.0, 23.5,
(1) characterized by an X-ray diffraction pattern with slightly strong peaks at 1 and 23.8 And (2) a method for dyeing a hydrophobic fiber, characterized by using the crystal modification of a dye represented by (2) above. Hereinafter, the crystal modification defined above is referred to as a β-type crystal. (In addition, an increase / decrease of ± 0.2 [°] in the display of the diffraction angle is allowed as a normal error range.)

In the present invention, the heat-labile crystal modification of the dye represented by the formula (1) before being converted into the β-type crystal (hereinafter referred to as α-type crystal) is converted into 2-chloro-4-nitroaniline by a known method. Diazotization, 3-in acidic medium
Obtained by coupling with N-cyanoethyl-N-acetoxyethylamino-acetanilide.
This α-type crystal has a so-called undulating peak as shown in FIG. 2 in an X-ray diffraction method using Cu-Kα ray, and is a so-called amorphous type. This dye is mechanically atomized with a dispersant, for example, a soda salt of a formalin condensate of naphthalene sulfonic acid or a soda salt of lignin sulfonic acid by a sand mill or the like according to a usual method for producing a polyester fiber woven fabric or When used for dyeing a blended fiber fabric of polyester fiber and acrylic fiber or cotton, the α-type crystal dye is unstable to heat,
At a temperature of 95 to 135 ° C. at which the polyester fiber is dyed, crystal conversion occurs and the dye particles are tarned or aggregates are formed.

Such tar products and dye particles agglomerated and coarsened often impede uniform dyeing. Especially in Overmeier dyeing, cheese dyeing, beam dyeing, jet dyeing, etc., tarred dyes and particles that have agglomerated are filtered by the fiber layer, clogging, poor internal penetration,
This causes casing spots and the like, which not only does not give a uniform dyed product but also causes inconveniences such as a decrease in the fastness of the dyed product. In the present invention, as a result of intensive studies to improve such drawbacks and sufficiently meet market demands, it was found that β-type crystals specified in the above X-ray diffraction pattern are extremely excellent in dyeing stability at high temperature. It has been found.

The present invention will be described in detail. The β-type crystal of the dye represented by formula (1), which is stable to dyeing at high temperature, is a wet cake or a dry cake of α-type crystal obtained by coupling by diazotization by a known method, and then a water-soluble organic solvent or anion Alternatively, it is usually obtained by heating at a temperature of 40 ° C. or higher in water containing a nonionic surfactant. The processing time can be lengthened or shortened as required. For example, heat treatment at 40 ° C. or higher and 200 ° C. or lower, preferably 50 ° C. or higher and 100 ° C. or lower for 1 to 3 hours converts α-type crystals into β-type crystals. At this time, heating to 100 ° C. or higher and prolonging the treatment time can be performed, but the effect is not significantly affected and it is not economically advantageous.

Examples of water-soluble organic solvents that can be used are lower alcohols such as methanol, ethanol, isopropyl alcohol and butyl alcohol, ethylene glycol monoalkyl ethers such as methyl cellosolve, ethyl cellosolve and butyl cellosolve, and glycols such as ethylene glycol. Examples thereof include ketones such as acetone and methyl ethyl ketone, and cyclic ethers such as tetrahydrofuran and dioxane. Examples of anionic surfactants that can be used include β-naphthalenesulfonic acid formalin condensate salts and ligninsulfonic acid salts, and examples of nonionic surfactants include sorbitan fatty acid esters and polyoxyethylene sorbitan fatty acid. Examples thereof include esters, polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenols, polyoxyethylene alkyl amides, and the like. These alone,
It is also possible to use two or more types in combination.

Crystal conversion from α-type crystals to β-type crystals may be carried out by using a wet cake obtained by filtering and washing with water after the coupling reaction or a dried cake thereof, or by performing the coupling reaction without a filtering step. It is also possible to carry out the heat treatment as it is, or after the necessary amount of the water-soluble organic solvent, anion or nonionic surfactant is added to the reaction liquid, and then heat treatment. If the coupling reaction is not adversely affected, the organic solvent or surfactant may be added prior to the coupling reaction to heat the reaction solution itself at a relatively low temperature after the completion of the coupling reaction. A crystal conversion from an α-type crystal to a β-type crystal is possible by treatment (for example, 30 to 40 ° C.). Usually, the water-soluble organic solvent is 5 to 50% by weight with respect to water, and the surfactant is 0.1 to 5 with respect to water.
Used by adding 0% by weight. The amount of the aqueous medium used relative to the dye to be crystallized is usually 0.5 to 100% by weight, preferably 1.5 to 50% by weight (based on the dry dye).

Whether or not the conversion into the β-type crystal is completed in the present invention can be easily confirmed by measuring the X-ray diffraction spectrum.

Fibers which can be dyed with the β-type crystal-containing dye of the present invention include, for example, polyethylene terephthalate fiber, or a blended product or a blended product of this and a natural fiber such as cotton, silk or wool.

The dyeing of the hydrophobic fiber using the crystal modification dye having the β-type crystal having the structural formula (1) of the present invention is usually formalin condensate of naphthalenesulfonic acid, formalin condensate, higher alcohol sulfate ester, higher alkylbenzene sulfonic acid. A β-type crystal dye cake is finely dispersed in an aqueous medium in the presence of a dispersant such as a salt to prepare a dyeing bath or a printing paste, and the dyeing bath or the printing paste is used to carry out the dyeing method or the printing method. In the case of dip dyeing, it can be applied to dyeing methods such as a high temperature dyeing method, a carrier dyeing method and a thermosol dyeing method. In dyeing, the dye of the formula (1) of the β-type crystal of the present invention may be used in combination with other dyes, and various compounding agents may be added in the disperse dye preparation step.

According to the dyeing method of the present invention, the stability of the dye particles to heat is excellent, which is caused by clogging, poor penetration, casing spots, etc. particularly in dyeing methods such as overmeier dyeing, beam dyeing and jet dyeing. Does not cause uneven dyeing.

[0014]

EXAMPLES The present invention will be described in more detail with reference to the following examples. Example 1 173 g of 2-chloro-4-nitroaniline were added to 250 g of concentrated hydrochloric acid and 350 g of ice water with stirring, and then an aqueous solution containing 69 g of sodium nitrite in 250 g of water was added at 0-5 ° C. to diazo. A liquid chemical was obtained. Further, an acetic acid solution of 289 g of 3-N-cyanoethyl-N-acetoxyethylamino-acetanilide containing 200 g of acetic acid was added dropwise to the diazo solution while appropriately adding ice so that the temperature was kept at 5 ° C or lower,
Coupling was performed. After the reaction was completed, the mixture was neutralized to the neutrality with Congo red with sodium carbonate, filtered and washed with water to obtain 425 g of dye cake (corresponding to dryness).

The X-ray diffraction pattern of this cake by the powder method was an amorphous α-type crystal as shown in FIG. The dye cake is then dispersed in 10 liters of water and stirred at 70
Heat treatment was performed at -80 ° C for 2 hours. After this treatment, the cake was filtered to give crystals. As a result of analyzing this crystal according to the powder X-ray diffraction method, it was a β-type crystal having an X-ray diffraction chart as shown in FIG.

Example 2 Wet cake 21 of α type crystals obtained by the same method as in Example 1
g (dry equivalent), 21 g of naphthalene sulfonic acid formalin condensate (dispersing agent), 28 g of naphthalene sulfonic acid / cresol sulfonic acid formalin condensing agent (dispersing agent), and 300 g of water are heated at 70 to 80 ° C. for 2 hours. Then, a part thereof was filtered, washed with water and then dried under reduced pressure. The X-ray diffraction diagram of the obtained dye crystal was similar to that of FIG. 1 and was of β type. 3 g of the dye composition obtained by grinding the heat treatment liquid with a sand grinder and then spray drying was dispersed in 3 liters of water and adjusted to pH 5 with acetic acid and sodium acetate to obtain a dye bath. 100 g of the cloth was dipped and dyed at 130 ° C. for 60 minutes. When it was subjected to sorbing, washing with water and drying, a red dyed cloth uniformly dyed was obtained.

Example 3 In place of the dispersant for crystal conversion in Example 2, 7.5 g of Rheidol TW-0 (polyoxyethylene sorbitan nonionic surfactant, manufactured by Kao Atlas) was used. The same operation was performed to obtain a β type crystal.

Example 4 In the same manner as in Example 2, except that 30 g of ethylene glycol monomethyether was used instead of the dispersant for crystal conversion in Example 2, β-type crystals were obtained.

Example 5 Coupling was carried out in the same manner as in Example 1, and the coupling liquid was subsequently stirred at 70 to 80 ° C. for 2 hours. The crystals of the dye obtained by filtration and washing with water showed β type.

Example 6 A diazo solution was prepared in the same manner as in Example 1, and then a coupler solution obtained by adding 25 g of Leodol TW-0 to an acetic acid solution containing a predetermined coupler was added to the diazo solution at 5 ° C. or lower. Coupling was performed by dropping. After the dropping was completed, the mixture was kept at 0 to 5 ° C for 2 hours, and then neutralized to neutrality with Congo red with sodium carbonate. Further, this reaction liquid was kept at 30 to 35 ° C. for 10 hours, filtered and washed with water. The crystals of the obtained dye were β type.

Example 7 and Comparative Example 21 g of each α-type or β-type dye, 21 g of naphthalenesulfonic acid formalin condensate and 28 g of naphthalenesulfonic acid / cresolsulfonic acid formalin condensate were mixed and wet-ground with a sand grind mill. Then, they were vacuum dried to obtain disperse dye compositions. In order to compare the stability of each of the obtained dye compositions against heat, (1) thermal cohesiveness test and (2) casing dyeing test were performed.

Table 1 Crystal-type thermal agglutination test Casing dyeing test β-type crystal Grade 5 Grade 4 α-type crystal Grade 3 grade 3-4 The details of each test method are as follows.

(1) Thermal Coagulation Test 0.5 g of each disperse dye composition was dispersed in 100 ml of water and the pH was adjusted to 4.5 with acetic acid and sodium acetate. (Blank bath) From 60 ° C to 130 ° C over 40 minutes, hold at the same temperature for 10 minutes,
Cool to 95 ° C in 5 minutes and filter with a quantitative filter (Toyo Filter Paper No. 5
A) was used for suction filtration, and the series was determined from the amount and state of the residue on the filter paper. According to the 5 grade display from 5 grade (good) to 1 grade (bad).

(2) Casing dyeing test 0.6 g of each disperse dye composition was dispersed in 180 ml of water, and 10 g of Tetron jersey was dipped in a dye bath prepared by adjusting the pH to 4.5 with acetic acid and sodium acetate. The temperature was adjusted to 130 ° C over 40 minutes (using a color pet dyeing machine) for 40 minutes, kept at the same temperature for 10 minutes, cooled to 60 ° C, and then washed with water to obtain a dyed product. In this dyeing, the quality of the casing spot was judged from the state of the agglomerates attached to the material to be dyed at the portion inscribed in the material holder. Grade 5 (good) to Grade 1 (bad)
According to the 5 step display. As is clear from the table, β of the present invention
The type crystals gave better results in both thermal agglomeration and casing spots than the α type crystals.

[0025]

The heat-stable crystal modification (β type crystal) of the dye represented by the formula (1) was obtained. When dyeing is performed using this crystal modification, a good dyed product without uneven dyeing can be obtained.

[Brief description of drawings]

FIG. 1 is an X-ray diffraction diagram of a heat-stable β-type crystal.

FIG. 2 is an X-ray diffraction diagram of a thermally unstable α-type crystal (amorphous type). 1 and 2, the horizontal axis represents the diffraction angle 2θ
[°] is shown, and the vertical axis shows the diffraction strength.

Claims (2)

[Claims] 1. A strong peak at a diffraction angle [°] of 25.4 and a diffraction angle (2θ) in a powder X-ray diffraction method using Cu-Kα rays.
[°] 10.5, 15.7, 18.6, 23.0, 2
Crystal modification of the dye of formula (1) characterized by X-ray diffractograms with rather strong peaks at 3.5 and 23.8 2. A method for dyeing a hydrophobic fiber, which comprises using the crystal modification according to claim 1.