JP3638306B2

JP3638306B2 - Monoazo dye compound

Info

Publication number: JP3638306B2
Application number: JP12443294A
Authority: JP
Inventors: 清姫野; 貴司森
Original assignee: ダイスタージャパン株式会社
Priority date: 1994-05-13
Filing date: 1994-05-13
Publication date: 2005-04-13
Anticipated expiration: 2020-04-13
Also published as: JPH07304990A

Description

【０００１】
【産業上の利用分野】
本発明はモノアゾ染料化合物に関するものである。詳しくは、高温で苛酷な条件でもポリエステル繊維等を均一に染色することのできる新規な結晶構造を有する青色系モノアゾ染料化合物に関するものである。
【０００２】
【従来の技術】
近年、染色業界では染色法に種々の合理化が行われており、例えば、分散染料を用いてポリエステル繊維を染色する場合に於ては、布用としては液流染色法、糸用としてはチーズ染色法又はパッケージ染色法等があり、広く行われている。これらの染色法は、静止した繊維を何層にも巻いた緻密な層内に、染色分散液を強制的に循環させて染色させる方式であるため、従来以上に、染色浴に分散した染料粒子が微粒子であること及び染色浴における分散安定性が優れていることが要求される。もし、染料粒子が大きくなると、繊維層によって染料粒子の濾過現象が起り、繊維内部への染料の浸透不良、あるいは凝集物の付着による内層または外層の濃淡染め、繊維表面のみへの染料の付着による耐摩擦堅牢度などの堅牢度の低下などの問題が発生する。
【０００３】
従って、このような染色法に使用する染料は、染浴中で分散が良好であり、かつ室温から実際の染着が起こる高温度までの広い温度範囲において分散性が低下しないことが必要である。
ところが、一般的に、染色浴中で高温度にした時、染料の分散性は、往々にして低下しやすく、その結果、凝集した染料が上述したように被染物の表面に濾過残渣状に付着し、また何層にも重なっている被染物は、外層部分と内層部分で染着濃度が異なり、均一な濃度の染色物が得られない。
【０００４】
特に最近は、省資源、省エネルギーの観点から、▲１▼染色浴の低浴比化（被染物：染色液の比率を１：３０から１：１０に低下）、▲２▼分散剤の使用割合の低下（染料ケーキ：分散剤の比率を１：３から１：１に低下）、更に、▲３▼染色条件の一層の短時間高温化（１３０℃で１時間から１３５℃で０．５時間）など、染色条件が苛酷な条件に移行しつつあるが、これらの条件はいずれも、染料の分散安定性には不利に働く為、従来の染色法では比較的分散安定性の良好であった染料においても、より厳しい最近の染色条件下においては、分散安定性が不良となるものも少なくない。
例えば、下記構造式〔Ｉ〕
【０００５】
【化２】

【０００６】
で示される染料は、例えば、特公昭３９−１４９８９号公報記載の特許請求の範囲に包含されるものである。そしてこの染料は常法に従って単にジアゾ成分とカップリング成分とをカップリング反応させることにより製造されている。
このモノアゾ染料は従来の温和な染色条件においては、ポリエステル繊維を均一に染色することができ、しかも諸堅牢度も優れたものである。ところが上述のような高温度で、苛酷な条件下で染色を行なった場合には、染料の分散性の低下が著しく、均一な染色濃度の染色物を得ることが極めて困難である。
【０００７】
また、この染料は各種染色助剤との相溶性の点でも問題があり、例えば、芒硝存在下での高温分散安定性が著しく悪く、従って反応性染料等と併用してポリエステル／綿混紡品を芒硝の存在下に染色する際に不均染となる。更に、染料を配合し使用する際にも、配合染料との相溶性の点から色ブレ、不均染を発生する欠点があった。
【０００８】
【発明が解決しようとする課題】
本発明は上記欠点を解決した、高温度で苛酷な条件下でも良好な染色を行うことができる染料を提供するものである。
本発明者等は上記欠点に関して鋭意検討した結果、前記構造式〔Ｉ〕で示されるチオフェン系のモノアゾ化合物に於いて、従来の通常の合成反応で得られる無定形固体では得ることができない、高温度でしかも苛酷な染色条件下でも分散安定性が良好な新規な結晶構造を有する結晶を見い出した。
【０００９】
更に染料組成物の高温染浴中での分散状態の安定性は、染料粒子の大小のみではなく、結晶性に重大な関係があり、上記の新規な結晶構造を有する化合物を用いた場合に、初めて染料組成物の高温染浴中での分散安定性が達成できることを見い出し本発明に到達した。
【００１０】
【課題を解決するための手段】
即ち本発明は、回折角（２θ）約５．０°、２２．８°、２３．５°、２４．９°及び約２５．１°に強いピーク、更に約６．５°、８．０°、１１．３°、１４．４°、１７．０°、１８．０°及び約１９．６°に中強度のピークを示すＸ線回折図（ＣｕＫα）により特徴づけられる結晶構造を有する下記構造式〔Ｉ〕
【００１１】
【化３】

【００１２】
で示される水不溶性モノアゾ染料を要旨とする。
本発明の新規な結晶構造を有するモノアゾ化合物は以下のようにして得られる。例えば、２−クロロ−４，６−ジニトロアニリンを常法によりジアゾ化し、次いで、これを水性媒体中で０〜１５℃、好ましくは０〜１０℃の温度で０．５〜１０時間、カップラーである３−（Ｎ，Ｎ−ジエチルアミノ）−４−メトキシアセトアニリドとカップリング反応させることにより、前示構造式〔Ｉ〕のモノアゾ化合物を合成する。
【００１３】
この合成で得られるモノアゾ化合物のケーキは無定形構造であるが、本発明ではこのケーキを更に、特定条件下で処理することにより前記結晶構造を有する結晶を得る。
この処理方法としては、例えば、無定形構造のケーキを▲１▼水媒体中に分散し、場合により、ナフタレンスルホン酸のホルムアルデヒド縮合物、リグニンスルホン酸ソーダが主成分であるサルファイトパルプ廃液の濃縮物等の分散剤の存在下、６０〜１３０℃、好ましくは８０〜１００℃の温度で０．５〜３０時間、好ましくは１〜１０時間、攪拌処理する方法、又は▲２▼メタノール、エタノール又はブタノールなどのアルコール類、ジオキサンなどのエーテル類、エチレングリコール、グリコールエーテル等の有機溶媒中に分散し、１５〜１００℃、好ましくは２０〜８０℃の温度で０．５〜１０時間程度、攪拌処理する方法が採用される。
【００１４】
次に、前示構造式〔Ｉ〕で示されるモノアゾ化合物の無定形構造と結晶構造について図面より説明する。図１及び図２は粉体Ｘ線回折法におけるＣｕＫα線による回折状態をプロポーショナルカウンターを使用して記録したＸ線回折図であり、横軸は回折角（２θ）、縦軸は回折強度を示す。図１は本発明の新規な結晶形態を示すもので、特に、回折角（２θ）約５．０°、２２．８°、２３．５°、２４．９°及び約２５．１°に強いピーク、更に約６．５°、８．０°、１１．３°、１４．４°、１７．０°、１８．０°及び約１９．６°に中強度のピークを持っている。図２は従来の無定形構造を示すものであり、図１の結晶形態と明確に異っている。
【００１５】
Ｘ線回折法による回折角は、同一結晶型のものであれば、±０．１°程度の誤差で常に一致するものであって、これらの図面は結晶状態の相違を明白に示している。この結晶状態の差異により染色時におけるモノアゾ化合物の挙動が異なり、本発明の場合には、高温度で、しかも、苛酷な条件での染色法を採用しても、良好な染色ができるのである。
【００１６】
本発明のモノアゾ染料化合物により染色しうる繊維類としてはポリエチレンテレフタレート、ポリブチレンテレフタレート、テレフタル酸と１，４−ビス−（ヒドロキシメチル）シクロヘキサンとの重縮合物などよりなるポリエステル繊維、あるいは木綿、羊毛などの天然繊維と上記ポリエステル繊維との混紡品、混織品が挙げられる。本発明のモノアゾ染料を用いてポリエステル繊維を染色するには、常法により分散剤としてナフタレンスルホン酸のホルムアルデヒドとの縮合物、高級アルコール硫酸エステル、高級アルキルベンゼンスルホン酸塩などを用いて、水性媒体中に分散させた染色浴または捺染糊を調製し浸染又は捺染を行なうことができる。また、例えば、浸染の場合、上述のような高温染色法、キャリヤー染色法、サーモゾル染色法などの染色処理法を適用することができ、しかも、これらの方法で苛酷な染色条件を採用しても、本発明のモノアゾ染料は分散安定性に優れているので、ポリエステル繊維ないしはその混紡品を良好に染色することができる。具体的には、ポリエステル繊維類を染色温度１２５〜１４０℃、染浴比が１５倍以下、染料に対する分散剤の使用割合が３重量倍以下の苛酷な条件下で、水性媒体中、分散剤の存在下で吸尽染色することも可能である。
【００１７】
尚、場合により染色浴にギ酸、酢酸、リン酸、硫酸アンモニウムなどの酸性物質を添加すれば、更に好結果が得られる。
また、本発明の前示構造式〔Ｉ〕で示されるモノアゾ染料は他の染料と併用してよく、染料相互の配合により染色性の向上等好結果が得られる場合がある。
【００１８】
【実施例】
次に、実施例により本発明を更に具体的に説明する。
実施例１
（染料結晶の製造例）
９８％硫酸とニトロシル硫酸の混合溶液に６−クロロ−２，４−ジニトロアニリン５．６ｇを加え、２０°〜２５℃で２時間ジアゾ化させ、ジアゾ液を調製した。
一方、３−（Ｎ，Ｎ−ジエチルアミノ）−４−メトキシアセトアニリド５．５ｇを０．０５％の硫酸に溶解させ、カップリング溶液を調製した。このカップリング溶液に先に得られたジアゾ液をｐＨ４を保持する様に、２５％水酸化ナトリウム水溶液と共に滴下してカップリング反応させ、０℃で１時間攪拌して反応終了後析出固体を濾別、水洗、乾燥して緑色固体１０ｇを得た。
得られた前記一般式〔Ｉ〕で示される化合物固体の粉末をＸ線回折法により分析したところ無定形の固体であった。そのＸ線回折図を図−２に示す。
次いで、得られた無定形固体を２０倍容量の水中に分散させ、９０°〜９５℃で３時間攪拌し、結晶化処理を施した。得られた結晶をＸ線回折法により分析したところ図−１に示すＸ線回折図を示す結晶であった。
【００１９】
（染色例１）（苛酷な条件下での染色）
前記実施例１で得られた結晶構造を有するモノアゾ染料０．５ｇを、ナフタレンスルホン酸−ホルムアルデヒド縮合物０．２５ｇおよび高級アルコール硫酸エステル０．２５ｇを含む水１リットル中に分散させて染色浴を調製した。
この染色浴にポリエステル繊維１００ｇを浸漬し、１３５℃で３０分間染色した後、ソーピング、水洗および乾燥を行なったところ、染料の分散性は良好であり、染布への均一な染色がなされた。また、得られた染布は青色で、耐光堅牢度５級、耐摩擦堅牢度５級と良好なものであった。
なお、上記製造例の製造途中の無定形構造のモノアゾ染料を用いて、同様の染色試験をしたところ、染浴中で染料の部分凝集が起り、不均染な染布となり、かつ耐摩擦堅牢度は１級と大きく劣るものであった。
【００２０】
（染色例２）（通常の条件下での染色）
染色例１において、ナフタレンスルホン酸−ホルムアルデヒド縮合物および高級アルコール硫酸エステルをそれぞれ３倍の０．７５ｇに、水を３倍の３リットルとし、染色条件を１３０℃で６０分間とした以外は染色例１と同様にして、やや温和な染色法にて染色を行なった結果、本発明の結晶構造を有する染料では染色例１と同様に良好な染色ができ、得られた染布も耐光堅牢度５級、耐摩擦堅牢度５級と良好であった。これに対して、無定形構造の染料を用いた際には、染色例１に比べて僅かに向上が見られたが、やはり不均染が染布しか得られず、そのものの耐摩擦堅牢度は３級であった。
【００２１】
【発明の効果】
本発明の結晶構造を有する水不溶性モノアゾ染料は、従来の無定形のモノアゾ染料に比較して格段に分散安定性に優れ、高温度で、しかも、例えば被染物：染色液の比率が１：１０、染料ケーキ：分散剤の比率が１：１、染色条件が１３５℃で０．５時間といった苛酷な染色条件下でも分散安定性を維持することができ、従って常に良好な均一な染色が得られ、得られる染布は耐光堅牢度、耐摩擦堅牢度に優れたものである。従って、本発明の染料は、省資源、省エネルギーの観点から非常に有用なものである。
【図面の簡単な説明】
【図１】本発明の実施例において得られた結晶構造のモノアゾ化合物のＸ線回折図であり、図中、横軸は回折角（２θ）を、縦軸は回折強度を表わす。
【図２】本発明の実施例において得られた無定形構造のモノアゾ化合物のＸ線回折図であり、図中、横軸は回折角（２θ）を、縦軸は回折強度を表わす。[0001]
[Industrial application fields]
The present invention relates to monoazo dye compounds. Specifically, the present invention relates to a blue monoazo dye compound having a novel crystal structure capable of uniformly dyeing polyester fibers and the like even under severe conditions at high temperatures.
[0002]
[Prior art]
In recent years, various dyeing methods have been rationalized in the dyeing industry. For example, in the case of dyeing polyester fibers using disperse dyes, the liquid dyeing method is used for fabrics, and cheese dyeing is used for yarns. Method or package dyeing method, etc. are widely used. In these dyeing methods, dye particles dispersed in a dye bath are more than conventional because dyeing dispersion is forced to circulate in a dense layer of stationary fibers wound in layers. Are required to be fine particles and to have excellent dispersion stability in a dyeing bath. If the dye particles become larger, the filtration phenomenon of the dye particles occurs due to the fiber layer, the penetration of the dye into the fiber is poor, or the inner layer or the outer layer is lightly dyed due to adhesion of aggregates, due to the dye adhesion only to the fiber surface Problems such as a decrease in fastness such as friction fastness occur.
[0003]
Therefore, it is necessary that the dye used in such a dyeing method has good dispersion in the dye bath and that the dispersibility does not deteriorate in a wide temperature range from room temperature to a high temperature at which actual dyeing occurs. .
However, in general, when the temperature is increased in a dyeing bath, the dispersibility of the dye is often lowered, and as a result, the aggregated dye adheres to the surface of the object to be dyed as a filtration residue as described above. In addition, the dyed articles that overlap in several layers have different dyeing concentrations in the outer layer portion and the inner layer portion, and a dyed product having a uniform concentration cannot be obtained.
[0004]
Recently, from the viewpoint of resource saving and energy saving, (1) lowering of the bath ratio of the dyeing bath (the ratio of the object to be dyed: the dyeing liquid has been reduced from 1:30 to 1:10), and (2) the proportion of the dispersant used (Dye cake: dispersant ratio decreased from 1: 3 to 1: 1), and (3) further increased the temperature of dyeing conditions for a shorter time (from 130 ° C. for 1 hour to 135 ° C. for 0.5 hour) ) And other dyeing conditions are shifting to harsh conditions, but these conditions all work against the dispersion stability of the dye, so the conventional dyeing method has relatively good dispersion stability. Even in dyes, there are many cases where dispersion stability becomes poor under more severe recent dyeing conditions.
For example, the following structural formula [I]
[0005]
[Chemical formula 2]

[0006]
Is contained in the scope of claims described in Japanese Patent Publication No. 39-14989, for example. This dye is produced by a coupling reaction between a diazo component and a coupling component according to a conventional method.
This monoazo dye is capable of uniformly dyeing polyester fibers under conventional mild dyeing conditions and has excellent fastness. However, when dyeing is performed under severe conditions at high temperatures as described above, the dispersibility of the dye is remarkably lowered, and it is extremely difficult to obtain a dyed product having a uniform dyeing density.
[0007]
In addition, this dye has a problem in compatibility with various dyeing assistants. For example, the high-temperature dispersion stability in the presence of sodium sulfate is extremely poor. Therefore, a polyester / cotton blend can be used in combination with a reactive dye. Uneven dyeing occurs when dyeing in the presence of mirabilite. Further, when blending and using dyes, there is a drawback that color blur and uneven dyeing occur due to compatibility with the blended dyes.
[0008]
[Problems to be solved by the invention]
The present invention provides a dye that can solve the above-mentioned drawbacks and can perform good dyeing even under severe conditions at high temperatures.
As a result of intensive studies on the above drawbacks, the present inventors have found that the thiophene-based monoazo compound represented by the structural formula [I] cannot be obtained with an amorphous solid obtained by a conventional ordinary synthesis reaction. The inventors have found a crystal having a novel crystal structure with good dispersion stability under temperature and severe dyeing conditions.
[0009]
Furthermore, the stability of the dispersion state of the dye composition in the high-temperature dyeing bath has a significant relationship not only with the size of the dye particles but also with the crystallinity, and when the compound having the above novel crystal structure is used, For the first time, it was found that the dispersion stability of the dye composition in a high-temperature dyeing bath can be achieved, and the present invention has been achieved.
[0010]
[Means for Solving the Problems]
That is, the present invention has strong peaks at diffraction angles (2θ) of about 5.0 °, 22.8 °, 23.5 °, 24.9 ° and about 25.1 °, and further about 6.5 °, 8.0. The following crystal structure characterized by an X-ray diffractogram (CuKα) showing medium intensity peaks at °, 11.3 °, 14.4 °, 17.0 °, 18.0 ° and about 19.6 ° Structural formula [I]
[0011]
[Chemical 3]

[0012]
A water-insoluble monoazo dye represented by
The monoazo compound having a novel crystal structure of the present invention is obtained as follows. For example, 2-chloro-4,6-dinitroaniline is diazotized by a conventional method, and this is then subjected to a coupler in an aqueous medium at a temperature of 0 to 15 ° C., preferably 0 to 10 ° C. for 0.5 to 10 hours. A monoazo compound of the structural formula [I] is synthesized by a coupling reaction with certain 3- (N, N-diethylamino) -4-methoxyacetanilide.
[0013]
The monoazo compound cake obtained by this synthesis has an amorphous structure. In the present invention, the cake is further treated under specific conditions to obtain crystals having the crystal structure.
As the treatment method, for example, an amorphous cake is dispersed in (1) an aqueous medium, and in some cases, concentration of a sulfite pulp waste liquid mainly composed of a formaldehyde condensate of naphthalene sulfonic acid and sodium lignin sulfonate is used. In the presence of a dispersing agent such as a product at a temperature of 60 to 130 ° C., preferably 80 to 100 ° C., for 0.5 to 30 hours, preferably 1 to 10 hours, or (2) methanol, ethanol or Disperse in an organic solvent such as alcohols such as butanol, ethers such as dioxane, ethylene glycol, glycol ether, etc., and stir at a temperature of 15 to 100 ° C., preferably 20 to 80 ° C. for about 0.5 to 10 hours. Is adopted.
[0014]
Next, the amorphous structure and crystal structure of the monoazo compound represented by the structural formula [I] will be described with reference to the drawings. 1 and 2 are X-ray diffraction diagrams in which a diffraction state by CuKα rays in a powder X-ray diffraction method is recorded using a proportional counter. The horizontal axis indicates a diffraction angle (2θ), and the vertical axis indicates diffraction intensity. . FIG. 1 shows the novel crystalline form of the present invention, particularly strong at diffraction angles (2θ) of about 5.0 °, 22.8 °, 23.5 °, 24.9 ° and about 25.1 °. The peaks also have medium intensity peaks at about 6.5 °, 8.0 °, 11.3 °, 14.4 °, 17.0 °, 18.0 ° and about 19.6 °. FIG. 2 shows a conventional amorphous structure, which is clearly different from the crystal form of FIG.
[0015]
The diffraction angles obtained by the X-ray diffraction method always match with an error of about ± 0.1 ° if they are of the same crystal type, and these drawings clearly show the difference in crystal state. Due to the difference in crystal state, the behavior of the monoazo compound at the time of dyeing is different, and in the case of the present invention, good dyeing can be performed even if a dyeing method is used at a high temperature and under severe conditions.
[0016]
Examples of fibers that can be dyed with the monoazo dye compound of the present invention include polyethylene terephthalate, polybutylene terephthalate, polyester fiber made of polycondensate of terephthalic acid and 1,4-bis- (hydroxymethyl) cyclohexane, cotton, wool And blended products of natural fibers such as polyester fibers and the above-mentioned polyester fibers. In order to dye polyester fibers using the monoazo dye of the present invention, a condensate of naphthalene sulfonic acid with formaldehyde, a higher alcohol sulfate, a higher alkyl benzene sulfonate, or the like is used as a dispersant in an aqueous medium by a conventional method. It is possible to prepare a dyeing bath or printing paste dispersed in the ink and perform dyeing or printing. In addition, for example, in the case of dip dyeing, dyeing methods such as the high-temperature dyeing method, carrier dyeing method, and thermosol dyeing method described above can be applied, and even if severe dyeing conditions are adopted in these methods. Since the monoazo dye of the present invention is excellent in dispersion stability, it is possible to satisfactorily dye polyester fibers or blended products thereof. Specifically, the polyester fibers are dyed at a temperature of 125 to 140 ° C., the dye bath ratio is 15 times or less, and the ratio of the dispersant to the dye is 3 weight times or less under severe conditions in an aqueous medium. Exhaust dyeing in the presence is also possible.
[0017]
In some cases, better results can be obtained by adding acidic substances such as formic acid, acetic acid, phosphoric acid and ammonium sulfate to the dyeing bath.
Further, the monoazo dye represented by the structural formula [I] of the present invention may be used in combination with other dyes, and good results such as improvement in dyeability may be obtained by blending the dyes with each other.
[0018]
【Example】
Next, the present invention will be described more specifically with reference to examples.
Example 1
(Production example of dye crystal)
To a mixed solution of 98% sulfuric acid and nitrosyl sulfuric acid, 5.6 g of 6-chloro-2,4-dinitroaniline was added and diazotized at 20 ° to 25 ° C. for 2 hours to prepare a diazo solution.
Meanwhile, 5.5 g of 3- (N, N-diethylamino) -4-methoxyacetanilide was dissolved in 0.05% sulfuric acid to prepare a coupling solution. The diazo liquid obtained previously was dropped into this coupling solution together with a 25% aqueous sodium hydroxide solution so as to maintain a pH of 4, and a coupling reaction was carried out. The mixture was stirred at 0 ° C. for 1 hour. Separately, washed with water and dried to obtain 10 g of a green solid.
When the obtained powder of the compound solid represented by the general formula [I] was analyzed by X-ray diffraction, it was an amorphous solid. The X-ray diffraction pattern is shown in FIG.
Next, the obtained amorphous solid was dispersed in 20 times the volume of water and stirred at 90 ° to 95 ° C. for 3 hours for crystallization treatment. When the obtained crystal was analyzed by the X-ray diffraction method, it was a crystal showing the X-ray diffraction pattern shown in FIG.
[0019]
(Dyeing Example 1) (Dyeing under severe conditions)
A dye bath was prepared by dispersing 0.5 g of the monoazo dye having the crystal structure obtained in Example 1 in 1 liter of water containing 0.25 g of naphthalenesulfonic acid-formaldehyde condensate and 0.25 g of higher alcohol sulfate. Prepared.
After 100 g of polyester fiber was immersed in this dyeing bath and dyed at 135 ° C. for 30 minutes, soaping, washing with water and drying were carried out. As a result, the dispersibility of the dye was good and the dyeing cloth was evenly dyed. The dyed fabric obtained was blue and had good light fastness level 5 and friction fastness level 5.
In addition, when the same dyeing test was performed using a monoazo dye having an amorphous structure during the production of the above production example, partial agglomeration of the dye occurred in the dyeing bath, resulting in an uneven dyeing cloth, and resistance to friction. The degree was inferior to 1st grade.
[0020]
(Dyeing example 2) (Dyeing under normal conditions)
In Dyeing Example 1, dyeing examples except that naphthalenesulfonic acid-formaldehyde condensate and higher alcohol sulfate are tripled to 0.75 g, water is tripled to 3 liters, and the dyeing conditions are 130 ° C. for 60 minutes. In the same manner as in No. 1, dyeing was carried out by a slightly mild dyeing method. As a result, the dye having the crystal structure of the present invention could be dyed as well as in Dyeing Example 1, and the dyed fabric obtained had a light fastness of 5 Grade, fastness to friction, grade 5 and good. On the other hand, when the dye having an amorphous structure was used, a slight improvement was seen as compared with Dyeing Example 1. However, only uneven dyeing was obtained, and the friction fastness itself was obtained. Was grade 3.
[0021]
【The invention's effect】
The water-insoluble monoazo dye having the crystal structure of the present invention is far superior in dispersion stability as compared with conventional amorphous monoazo dyes, at a high temperature, and for example, the ratio of dyed object: dyeing solution is 1:10. The dispersion stability can be maintained even under severe dyeing conditions such as a ratio of dye cake: dispersing agent of 1: 1 and dyeing conditions of 135 ° C. for 0.5 hour, so that good uniform dyeing can always be obtained. The dyed fabric obtained is excellent in light fastness and friction fastness. Therefore, the dye of the present invention is very useful from the viewpoint of resource saving and energy saving.
[Brief description of the drawings]
FIG. 1 is an X-ray diffraction pattern of a monoazo compound having a crystal structure obtained in an example of the present invention, in which the horizontal axis represents a diffraction angle (2θ) and the vertical axis represents diffraction intensity.
FIG. 2 is an X-ray diffraction pattern of an amorphous monoazo compound obtained in an example of the present invention, in which the horizontal axis represents the diffraction angle (2θ) and the vertical axis represents the diffraction intensity.

Claims

Strong peaks at diffraction angles (2θ) of about 5.0 °, 22.8 °, 23.5 °, 24.9 ° and about 25.1 °, and further about 6.5 °, 8.0 °, 11.3 The following structural formula [I] having a crystal structure characterized by an X-ray diffraction diagram (CuKα) showing medium intensity peaks at °, 14.4 °, 17.0 °, 18.0 ° and about 19.6 °

A water-insoluble monoazo dye compound represented by

A method for dyeing polyester fibers, wherein the water-insoluble monoazo dye compound according to claim 1 is used.