Patent Application
20080022467
The present invention relates to novel disazo dyes of general formula (V)
wherein
Preferred are dyes of general formula (V), wherein
Particularly preferred are dyes of general formula (V), wherein
As substituent M, the cations of the alkali metals lithium, sodium and potassium are preferred, as well as the ammonium cation substituted by a hydroxy containing alkyl group having from 1 to 5 carbon atoms. Dyes having incorporated such a substituted ammonium cation show a particularly elevated The prepared dyes of general formula (V) are listed in Table 1 together with the position of their absorption maximum in aqueous solution.
The invention also relates to a method of preparation of the dyes of general formula (V) according to the invention, characterized by the fact that two units of the chromophore of general formula (VI),
wherein M and n are as defined above,
are condensed with one unit of cyanuric chloride in the presence of a base under formation of the intermediate dye compound of general formula (VII)
and
this intermediate dye compound of general formula (VII) is reacted subsequently with a compound of formula (VIII)
HX—(CH2)mSO3M (VIII)
wherein X, M and m are as defined above,
or of general formula (IX),
1,3,5-H2NC6H3(CO2M)2 (IX)
wherein M is as defined above,
under conditions that the dyes of general formula (V) are formed.
The disazo dyes of general formula (V) may be in the free acid form or in the form of inorganic or organic salts thereof. Preferably, they are in the form of their alkali or ammonium salts, wherein the ammonium cation may be substituted. Examples of such substituted ammonium cations are 2-hydroxyethylammonium, bis-(2-hydroxyethyl)-ammonium, tris-(2-hydroxyethyl)-ammonium, bis-(2-hydroxyethyl)-methylmmonium, tris-[2-(2-methoxyethoxy)-ethyl]-ammonium, 8-hydroxy-3,6-dioxactylammonium, 1,8-diazabicyclo(5.4.0)undec-7-en, 1,4-diazabicyclo-(2.2.2)-octane and tetraalkylammonium such as tetramethylammonium or tetrabutylammonium, or pyridinium.
The invention does not only relate to pure disazo dyes of general formula (V), but also to mixtures of these disazo dyes.
The disazo dyes of general formula (V) according to the invention are used for dying cellulose containing materials, paper, cotton, viscose, leather and wool to provide dyed materials with good water fastness and light stability.
All methods well known in the textile and paper industries for dyeing with substantive dyes may be used with the disazo dyes, preferably for the bulk or surface treatment of sized or unsized paper. The dyes may also be used in the dyeing of yarns and piece goods of cotton, viscose and linen by the exhaustion process from a long liquor or in a continuous process.
The invention furthermore relates to liquid dye preparations comprising at least one disazo dye of general formula (V) according to the invention. The use of such liquid dye preparations is particularly preferred for paper dyeing. Such stable, liquid, preferably aqueous, concentrated dye preparations may be obtained by using methods well known in the art, preferably by dissolving in suitable solvents. The possibility of preparation of such stable, aqueous, concentrated preparations in the course of dye synthesis itself, without intermediate isolation of the dye, for example after a desalting step by diafiltration of the reaction solution, is of particular advantage.
Such liquid dye preparations may not only contain disazo dyes of general formula (V), but, in addition, other yellow dyes such as Acid Yellow 17, Acid Yellow 23, Direct Yellow 132, Direct Yellow 86 or yellow dyes as described in patent applications WO 96/24,635 and EP 0,755,984.
Patent application WO 96/24,635 describes yellow dyes of general formula (X),
wherein
Patent application EP 0,755,984 describes yellow dyes of general formula (XI),
wherein
The disazo dyes or mixtures of disazo dyes of general formula (V) are excellent dyes for the preparation of yellow recording liquids for ink jet printing. These recording liquids may also contain other yellow dyes such as Acid Yellow 17, Acid Yellow 23, Direct Yellow 132, Direct Yellow 86 or yellow dyes as described in patent applications WO 96/24,635 and EP 0,755,984.
Such a yellow recording liquid comprises one or more of the disazo dyes according to the invention in a liquid aqueous medium and, optionally, other yellow dyes. The recording liquid contains from 0.5% to 20% by weight, preferably from 0.5% to 8% by weight, of these diazo dyes according to the invention, based on the total weight of the recording liquid. The liquid medium is preferably water or a mixture of water and water-miscible organic solvents. Suitable solvents are given for example in patents U.S. Pat. No. 4,626,284, U.S. Pat. No. 4,703,113 and U.S. Pat. No. 4,963,189 and in patent applications GB 2,289,473, EP 0,425,150 and EP 0,597,672.
Particularly preferred is a method of printing of textile materials with such a yellow recording liquid, wherein, in a first step, the ink is deposited on the textile material with the aid of an ink jet printer and, in a second step, the dye is fixed to the textile material by heating to a temperature from 60° C. to 130° C.
The present invention will be illustrated in more detail by the following examples without limiting the scope of the claimed disazo dyes in any way.
The intermediate dye compound of formula (XII)
was prepared in the following way:
614 g of the disodium salt of 3-[(4-aminophenyl)azo]-naphthalene-1,5-disulfonic acid (content 77.5%, 1.054 moles) were dissolved in 4900 ml of water at a temperature of 65° C. The warm solution (65° C.) was filtered through 20 g of silica gel under pressure. pH was adjusted to a value between 7.0 and 8.0. Then, the filtering device was rinsed with 100 ml of warm water and the filtrate was cooled down to a temperature of 0° C. 92.8 g of cyanuric chloride (0.504 moles) (available from Fluka Chemie GmbH, Buchs, Switzerland) were added portion-wise at a temperature between 0° C. and 50° C. while maintaining the value of pH between 4.0 and 6.0 by simultaneous addition of an aqueous solution (30%) of sodium hydroxide. The reaction mixture was warmed up to room temperature and finally heated to a temperature of 60° C. while maintaining the value of pH between 6.5 and 7.0 by simultaneous addition of an aqueous solution (30%) of sodium hydroxide. Stirring was continued for 2 hours at a temperature of 60° C. Afterwards, pH was adjusted to a value between 7.0 and 7.2 and the mixture was cooled down to a temperature of 20° C., and, finally, to a temperature of 5° C. The precipitate was vacuum filtered and vacuum dried at a temperature of 50° C. 573 g of the intermediate dye compound of formula (XII) were obtained in this way.
57 g (0.05 moles) of the intermediate dye compound of formula (XII) were suspended under stirring in 360 ml of water. Afterwards, 14.4 g of the sodium salt of 3-mercapto-propane-1-sulfonic acid, (available from Raschig GmbH, Ludwigshafen, Germany) (content 93%) were added and pH was adjusted to a value of 10.0 by addition of an aqueous solution (30%) of sodium hydroxide. Afterwards, 5.3 g of sodium carbonate were added to the mixture, the mixture was heated to a temperature of 80° C. and stirred for 5 hours at this temperature. pH was adjusted to a value of 6.5 by addition of acetic acid and the solution was clear filtered. The solution was cooled down to a temperature of 20° C. and the dye was precipitated by the addition of sodium acetate and methanol. The mixture was stirred for 2 hours and the precipitate was isolated by vacuum filtration. The precipitate was washed with a mixture (1:1 by volume) of water and methanol and finally vacuum dried at a temperature of 60° C. 35 g of the disazo dye No. 10 were obtained in this way.
114 g (0.10 moles) of the intermediate dye compound of formula (XII) of example 1 were suspended under stirring in 300 ml of water. The suspension was stirred for 30 minutes at a temperature of 20° C. Afterwards, a mixture of 17.5 g of taurine (0.14 moles), 280 ml of water and 16 g of an aqueous solution (30%) of sodium hydroxide and 16.0 g of sodium carbonate was added and the mixture was heated under reflux to a temperature of 100° C. The turbidity of the mixture disappears at a temperature of 70° C. The mixture was stirred for 2 hours at a temperature of 100° C. and afterwards cooled down to a temperature of 70° C. pH was adjusted to a value between 5.5 and 6.0 by addition of acetic acid. Stirring of the mixture was continued overnight. The orange precipitate was isolated by vacuum filtration.
The wet precipitate was suspended in 600 ml of water and the mixture was heated to a temperature of 70° C. pH was adjusted to a value of 8.0 by addition of an aqueous solution (30%) of sodium hydroxide. Afterwards, 4 g of silica gel were added to the turbid solution. The mixture was clear filtered at a temperature of 600° C. The filtering device was rinsed with 20 ml of water. 860 ml of ethanol (95%) were added drop-wise to the filtrate at a temperature of 60° C. The mixture was cooled down to a temperature of 5° C. and stirred for 1 hour at this temperature. The precipitate was vacuum filtered. The precipitate was washed with 140 ml of ethanol (95%) and finally vacuum dried at a temperature of 70° C. 112 g of the disazo dye No. 11 were obtained in this way.
The disazo dyes No. 12 to No. 18 according to the invention may be prepared in a similar way by using appropriate starting materials.
The present invention, as far as it relates to recording liquids, is illustrated by the following examples using the disazo dyes of Table 1 according to the invention and dyes representing the state of the art. For each dye, 100 g of recording liquid were prepared by heating the necessary amount of dye (2.0 g-5.0 g), 6.0 g of ethylene glycol, 3.0 g of propylene-1,2-glycol, 3.0 g of 1-methyl-2-pyrrolidone, 0.3 g of an aqueous solution (50%) of Olin® 10G (available from Arch Chemicals Inc., Norwalk, USA), 0.3 g of Surfinol® 465 (available from Air Products and Chemicals Inc., Allentown, USA) and 0.1 g of Mergal® K 10N (available from Riedel-de-Haën, Seelze, Germany) together with water at a temperature of 50° C. under stirring for approximately 1 hour. The resulting solution was cooled down to a temperature of 20° C., its value of pH was adjusted to 7.5 and the solution was passed through a Millipore® filter of 0.3 μm pore diameter. The dye quantity was adjusted in such a way that the optical density of the printed image was similar for all dyes.
Homogeneously colored square patches with an approximate density of 1.40 were then printed, using these recording liquids, with an ink jet printer Canon BJC 8500 onto the following recording sheets:
These colored patches were used for the determination of light stability, dye saturation and resistance against degradation by ozone.
Dye solubility was determined with a spectrophotometer in the UV and in the visible spectral region. The spectra of the pure disazo dyes according to the invention were measured in a buffered aqueous solution at a value of pH of 7.0. Saturated aqueous solutions of the dyes were prepared at a temperature of 50° C. These solutions were afterwards cooled down to room temperature and diluted for the measurements after a waiting time of 24 hours in such a way that the absorption at the absorption maximum was between 0.8 and 1.5. This dilution factor allows the calculation of dye solubility.
The color coordinates L*a*b* of the colored square patches were measured with a spectrophotometer Spectrolino® (available from Gretag Macbeth, Regensdorf, Switzerland) in reflection (illuminant D65). The saturation C* is determined from measured color coordinates according to the expression
C*=√{square root over (a*2+b*2)}
The printed samples were irradiated using a Weather-Ometer® Ci35A (available from Atlas Material Testing Technology, Chicago, USA) with a 6500 W xenon lamp at a temperature of 20° C. and relative humidity of 50% until an illumination of 20 megalux hours was reached. The density loss was measured with a densitometer Spectrolino®. The percent density loss of initial density gives an indication of the light stability of the dyes on the printed recording sheet.
For this test, colored square patches of 1 cm2 of integral density 1.4 containing a finely graded grid were printed with a Canon BJC 8500 ink jet printer, wherein the squares of this grid had a length of 8 pixels and the lines a width of 2 pixels. The printed samples were dried for 24 hours at a relative humidity of the air of 59%. The optical density of the colored square patches was measured with a Spectrolino® densitometer. The printed samples were then stored for 7 days in a climatic test cabinet WK 111 (available from Weiss Umwelttechnik GmbH, Reiskirchen-Lindenstruth, Germany) at a temperature of 40° C. and relative humidity of 80%. During storage, dye may diffuse into the white parts of the grid, giving a density increase. The samples were re-measured after storage. The density increase in percent before and after storage is a measure of the amount of dye diffusion.
The optical density of the colored square patches was measured with a Spectrolino® densitometer. Afterwards, the printed samples were stored for a predetermined time (for example 48 hours) in an ozone chamber, model 903 (available from Satra/Hampden, Great Britain) at a temperature of 30° C., a relative humidity of the air of 50% and an ozone concentration of 1 ppm at a velocity of the circulating, ozone containing air of 13 mm/s. After storage, the samples were re-measured. The density differences of these two measurements, expressed as per cent of the initial density, are an indication of the amount of dye loss due to the exposure to ozone.
For each of the above tests, the dyes may be classified into 4 classes:
The determined solubility of the disazo dyes according to the invention and a few dyes representing the state of the art is listed in Table 2.
A comparison of the results in Table 2 immediately shows that all the disazo dyes according to the invention have an excellent or a good solubility. Only dye (IV), representing the state of the art, has en equally high water solubility.
The determined color saturation C* of the disazo dyes according to the invention and a few dyes representing the state of the art are listed in Table 3.
A comparison of the results in Table 3 immediately shows that, in particular, the disazo dyes No. 10, 11 and 14 according to the invention are very brilliant and therefore give brilliant yellow colors on all recording sheets. None of the dyes representing the state of the art gives such brilliant yellow colors on all recording sheets.
The measured light stabilities of the disazo dyes according to the invention and a few dyes representing the state of the art are listed in Table 4.
A comparison of the results in Table 4 immediately shows that all disazo dyes according to the invention have an excellent or good light stability on all recording sheets. Only dye (I), representing the state of the art, has an excellent or good light stability on all recording sheets. The dyes (II), (III) and (IV), representing the state of the art, have a satisfactory or even unsatisfactory light stability on all recording sheets. They cannot therefore be used without restrictions in recording liquids for ink jet printing.
The measured amounts of dye diffusion of the disazo dyes according to the invention and a few dyes representing the state of the art are listed in Table 5.
A comparison of the results in Table 5 immediately shows that, in particular, the disazo dyes No. 11 and No. 14 according to the invention have an excellent or good diffusion fastness on all recording sheets. They may therefore be used without restrictions in recording liquids for ink jet printing. All dyes representing the state of the art have a satisfactory or even unsatisfactory diffusion fastness on at least one recording sheet. They cannot therefore be used without restrictions in recording liquids for ink jet printing.
The resistance against degradation by ozone of the disazo dyes according to the invention and a few dyes representing the state of the art is listed in Table 6. Because degradation by ozone is a problem only for nanoporous recording sheets, results are listed only for recording sheets C, D, F and G.
A comparison of the results in Table 6 immediately shows that all disazo dyes according to the invention have an excellent or good resistance against degradation by ozone on all recording sheets. They may therefore be used without restrictions in recording liquids for ink jet printing.
Finally, variations from the examples given herein are possible in view of the above disclosure. Therefore, although the invention has been described with reference to certain preferred embodiments, it will be appreciated that other dyes may be devised, which are nevertheless within the scope and spirit of the invention as defined in the claims appended hereto.
The foregoing description of various and preferred embodiments of the present invention has been provided for purposes of illustration only, and it is understood that numerous modifications, variations and alterations may be made without departing from the scope and spirit of the invention as set forth in the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 06118014.7 | Jul 2006 | EP | regional |
