GB2099010A

GB2099010A - Dis-azo compound

Info

Publication number: GB2099010A
Application number: GB8211127A
Authority: GB
Original assignee: Mitsubishi Kasei Corp
Current assignee: Mitsubishi Kasei Corp
Priority date: 1981-04-23
Filing date: 1982-04-16
Publication date: 1982-12-01
Also published as: DE3214814A1; DE3214814C2; CH648308A5; GB2099010B; JPS57177059A; JPS6363595B2

Abstract

A dis-azo compound represented by the formula: <IMAGE> the compound having a crystal modification characterized by the X- ray diffraction pattern which shows four intense peaks at the diffraction angles (2 theta ) of 9.1 DEG , 14.5 DEG , 24.2 DEG , and 24.9 DEG and seven peaks of intermediate intensity at the diffraction angles (2 theta ) of 5.5 DEG , 16.7 DEG , 17.3 DEG , 18.5 DEG , 19.5 DEG , 21.3 DEG , and 31.7 DEG . The compound is prepared from another crystalline form having weaker diffraction peaks, by stirring it at 15 DEG to 140 DEG C for 0.5 to 30 hours dispersed in water or an organic solvent. The compound is well dispersable in water and gives good blue dyeing of natural fibers or polyester.

Description

SPECIFICATION Dis-azo compound The present invention relates to a dis-azo compound having a specific crystal modification.

Recently, the dyeing industry is rationalized and jet dyeing capable of dyeing a large amount of fibers at once is generally employed. Such a dyeing technique includes beam dyeing, cheese dyeing, and package dyeing, which are conventional dyeing methods. According to these dyeing methods, the dye dispersed solution is forced to circulate through a large number of dense layers of fibers, and good results are obtained so long as the dye particles are fine particles and the dispersion system is stable, thereby uniformly circulating the solution through the fiber layers.On the contrary, if the dye particles are large particles, the dye particles are filtered out by the fiber layers, resulting in causing some problems such as poor penetration of dye into fibers, non-uniform dyeing of inner layers and outer layers due to adhering of aggregates and lowering of fastness due to dying of fiber surface only. Therefore, a dye used in such dyeing methods is required to have good dispersibility in the dye bath and to keep the good dispersibility over a wide temperature range from room temperature to high temperatures at which the dyeing actually occurrs. However, the dispersibility of the due tends to lower when the dyeing bath is heated to high temperatures.As the result, aggregated dye particles adhere on the surface of the fibers dyed in the form of filtering residues and in the case of dyeing a multi-layered article, the dyeing concentration is different between the outer layer portion and the inner layer portion and a uniformly dyed article cannot be obtained.

U.S. Patent 4,264,495 discloses a dis-azo compound represented by the formula (I):

The dis-azo compound produced according to the process disclosed in U.S. Patent 4,264,495 has a disadvantage that when the dye bath is heated to high temperatures, the dispersibility is greatly lowered, making it difficult to peform uniform dyeing.

As a result of extensive studies to overcome the disadvantages of the prior art, it has been found that the dis-azo compound has at least two kinds of crystal modifications, one being unstable at high temperatures (which is hereinafter referred to as "P-modification" and is considered to be a mixture of several crystal modifications) and another being very stable at high temperatures (which is hereinafter referred to as "a-modification"), the stability of dispersed dye composition in a dye bath at high temperatures is dependent not only on the size of dye particles but also on the crystal modifications, and a stable dispersion in a dye bath can be established only when a compound of the a-modification is used.

The compound of a-modification disperses well without causing aggregation due to its thermal stability, even in the spray drying process at about 1 300C.

According to this invention provide a dis-azo compound represented by the formula:

the compound having the crystal modification (ct- modification) characterized by the X-ray diffraction pattern which shows four intense peaks at the diffraction angles (20) of 9.1 , 14.5 , 24.20, and 24.90 and seven peaks of intermediate intensity at the diffraction angles (20) of 5.5 1 6.70, 17.30, 18.50, 9.50, 21 .3 0 and 31.70.

In the accompanying drawings: Figures 1 and 2 are X-ray diffraction patterns of the ct-modification and p-modification of the dis-azo compound obtained in the examples of this invention. In the drawings, the horizontal axis represents the diffraction angle (20) and the vertical axis, the diffraction intensity.

The compound of a-modification of this invention can be produced by diazotizing a monoazo compound (II) represented by the formula:

in the conventional manner, coupling the resulting compound with N-ethyl-N-cyanoethylaniline (III) represented by the formula:

to yield /3-modification, and then treating the p-modification in an aqueous medium if desired, in the presence of a dispersant such as a naphthalenesulfonic acid-formaldehyde condensate or a concentrate of sulfite pulp waste liquid comprising sodium ligninsulfonate as a main component, or in an organic solvent such as an alcohol, e.g., methanol, ethanol or butanol; an ether, e.g., dioxane; glycol, e.g., ethylene glycol; or glycol ether, e.g., ethylene glycol monoethylether, at 15 to 1 400C for 0.5 to 30 hours.

The a-modification and p-modification of the dis-azo compound of this invention represented by the formula (I) are explained by reference to the drawings.

Figure 1 and Figure 2 are X-ray diffraction patterns obtained by the powder X-ray diffraction method in which the diffraction state by CuKa ray is recorded using a proportional counter. In the drawings, the horizontal axis represents the diffraction angle (20) and the vertical axis, the diffraction intensity. Figure 1 shows the X-ray diffraction pattern of cr-modification which shows four intense peaks at the diffraction angles (20) of 9.10, 14.50,24.20, and 24.90 and seven peaks of intermediate intensity at the diffraction angles (20)of5.50, 16.70,17.30,18.50, 19.50,21.30, and 31.70. Figure 2 shows the X-ray diffraction pattern of,3-modification which shows weak peaks only.These patterns indicate the apparent difference between the two crystal modifications in view of the fact that the diffraction angles by Xray diffraction method are almost consistent, with an error of about +0.10, if those are the same crystal form.

The fibers which can be dyed with the dis-azo compound of this invention includes polyester fibers comprising polyethylene terephthalate or a polycondensate of terephthalic acid and 1,4bis(hydroxymethyl)cyclohexane, and blended materials of natural fibers such as cotton, silk or wool and the polyester fibers.

Polyester fibers are dyed with the dis-azo compound of this invention in the manner such that the compound is dispersed into an aqueous medium using a dispersant such as a condensate of naphthalene sulfonic acid and formaldehyde, sulfuric acid ester of higher alcohol or higher alkylbenzenesulfonate in the conventional manner to prepare a dyeing bath or printing paste and the fibers are subjected to dip dyeing or printing. For example, in the case of dyeing, the conventional dyeing methods such as high temperature dyeing, carrier dyeing or thermosol dyeing can be employed to obtain dyed polyester fibers or blended fibers thereof having excellent fastness.

In this case, better results can be obtained, if desired, by adding an acidic substance such as formic acid, acetic acid, phosphoric acid or ammonium sulfate, to the dye bath.

The dye of this invention represented by formula (I) may be used in combination with dyes of the same type or different type. In some cases, blending of dyes provides good results such as improvement of dyeability and other performance.

The invention is now explained in more detail by reference to the following examples.

Percentages are by weight.

Example 1 9.12 g of a mono-azo compound represented by the formula:

was suspension dissolved in a mixture of 1 60 ml of 85% phosphoric acid and 200 ml of glacial acetic acid which was cooled to 5"C or less, and then 17.0 g of 40% nitrosyl sulfuric acid was gradually added thereto. The mixture was stirred at O to 20C for 4 hours and was added dropwise to 600 ml of 10% sulfuric acid solution containing 2 g of urea and 7.0 g of N-ethyl-Ncyanoethylaniline. After stirring the mixture at O to 30C for 3 hours, the reaction product was filtered out, washed with water and dried in vacuo at 300C to yield 15.0 g of dark red powder of the dis-azo compound represented by the formula (I):

It was confirmed that the powder was of the ,B- modification.The X-ray diffraction pattern of the powder is shown in Figure 2.

7 g of the powder of the ss-modification was dispersed into a mixture of 30 ml of water and 200 ml of methanol, and the dispersion was stirred at 250C for 8 hours to cause crystal transition. After the crystal transition, the crystals were filtered out and dried to give crystals of,a- modification, the X-ray diffraction pattern of which is shown in Figure 1.

A dye bath was prepared by dispersing 0.5 g of the dis-azo compound of a-modification represented by the formula (I) into 3 1 of water containing 1 g of naphthalenesulfonic acidformaldehyde condensate and 2 g of higher alcohol sulfate ester. 100 g of polyester fibers was dipped in the dye bath to dye at 1 300C for 60 minutes, followed by soaping, washing with water and drying to obtain clear blue colored fibres having good fastness to light.

Further, a dyeing solution was prepared by dispersing 0.5 g of the dis-azo compound of amodification represented by the formula (I) into 3 I of water containing 1 g of naphthalenesulfonic acid-formaldehyde condensate and 2 g of higher alcohol sulfate. 100 g of polyester fibers were uniformly wound on a beam pipe in a beam dyeing device and the dyeing solution was added to the beam dyeing device. Dyeing was performed by circulating the dyeing solution at 1 300C for 45 minutes. After soaping, washing with water and drying, a clear blue colored fibers having good fastness to light were obtained.

For the sake of comparison, the same beam drying, clear blue colored fibers having good compound of p-modification and, as a result, dark blue colored fibers having spots of dyes were obtained.

Example 2 The ,5-modification compound obtained in the same manner as in Example 1 was treated in the same manner as in Example 1 except that the compound was dispersed in water and stirred at 900C for 5 hours, to obtain the compound of a modification.

Using the compound of a-modification thus obtained, polyester fibers were subjected to dip dyeing and beam dyeing in the same manners as in Example 1. In two dyeing operations, clear blue colored fibers having good fastness were obtained.

Claims

1. A dis-azo compound represented by the formula:

said compound having a crystal modification characterized by the X-ray diffraction pattern which shows four intense peaks at the diffraction angles (20) of 9.10, 14.50,24.20, and 24.90 and seven peaks of intermediate intensity at the diffraction angles (20) of 5.5 , 16.70, 1 7.30, 18.50, 1 9.50, 21.30 and 31.7

2. A method of preparing a compound as claimed in Claim 1, substantially as hereinbefore described in Example 1 or 2.

3. A method of dyeing a fabric, wherein an aqueous dispersion of a compound as claimed in Claim 1 is used.