JP2003128962A - Ink composition and method for ink-jet dyeing using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink composition capable of affording a highly sharp printed image, sufficient preservation stability without causing nonjetting even in printing for a long time, a small amount of bubbles even if shaken and having a short time for small bubbles to disappear. SOLUTION: This ink composition comprises a disperse dye dispersible with at least a dispersing agent, a water-soluble organic solvent, a surfactant and water. In the ink composition, at least a compound represented by formula I (wherein, m is 1-5; n is 1-10; p is 0-12; and X<+> is one kind selected from hydrogen ion, an alkali metal ion and an amine compound ion) is contained in the dispersing agent for the disperse dye. At least a compound represented by formula II (wherein, a+b is 0-30) is contained in the surfactant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disperse dye ink composition for ink-jet dyeing, which is applied to a fabric that can be dyed with a disperse dye, and more particularly to an ink for on-demand ink jet printing. .

[0002]

2. Description of the Related Art Today, ink jet dyeing has been put into practical use in which ink containing a dye corresponding to a cloth to be dyed or printed is used, and ink is directly printed on the cloth without making a plate.

The printing apparatus used here is roughly classified into a continuous type and a (drop) on-demand type. In general, a continuous-type printing device is one in which ink is always ejected from a nozzle, and by controlling the electric charge of the ink in the form of drops or by controlling the electric field in the space where ink drops fly, It is possible to change the printing position of the drops and to collect the ink and return it to the ink tank. Therefore, a single nozzle can cover a wide print area, but the device tends to be complicated.

On the other hand, an on-demand type printing apparatus is, as its name suggests, generally only by ejecting ink droplets straight from a nozzle when necessary, so that the apparatus is simple, but the printing speed is increased. Then, it is necessary to provide many nozzles. Therefore, a highly reliable ink that does not clog the nozzles is required more than the continuous system.

The inventors of the present invention have studied the ink composition using the disperse dye for ink jet dyeing according to Japanese Patent Publication No. 1-23507 in order to dye the disperse dye dyeable cloth made of synthetic fiber such as polyester by ink jet dyeing. As a result of addition, such an ink composition does not cause any particular problem in the continuous system, and when combined with a cloth pretreated with a cationic substance, a high sharp image without bleeding can be obtained, but in the on-demand system. It was found that ejection failure occurs after long-term use. Further, the storage stability of the ink composition cannot be said to be sufficient for the ink composition, and precipitation of the disperse dye was observed when the ink composition was left standing, which was also considered to be the cause of ejection failure of the nozzle. This means that, assuming a case where a large amount of ink composition is prepared and stored, the dye concentration becomes non-uniform in the storage container due to sedimentation, and depending on how the ink composition is taken out, an ink composition having a different concentration is obtained each time. Will be taken out, which causes a problem in use.
Furthermore, when the storage container was shaken in order to redisperse the disperse dye settled at the bottom of the container for storing the ink composition, a large amount of bubbles were generated. In an on-demand system of a type that does not have a forced supply mechanism of an ink composition such as a pump, when air bubbles enter the ink flow path, the supply of the ink composition is disturbed and ejection may not be performed. for that reason,
I had to wait a very long time for the bubbles that formed, especially the smaller ones, to disappear.

[0006]

SUMMARY OF THE INVENTION Therefore, the object of the present invention is to solve the above-mentioned problems, to obtain a highly sharp print image, to prevent ejection failure even after long-time printing, and to provide sufficient storage stability. Even if it shakes, the amount of foaming is small,
An object of the present invention is to provide an ink composition in which it takes a short time until small bubbles disappear, and an inkjet dyeing method using the ink composition.

[0007]

As a result of intensive studies, the present invention solves the above problems by the following gist.

That is, the ink composition of the present invention is an ink composition containing at least a disperse dye dispersed by a dispersant, a water-soluble organic solvent, a surfactant and water, wherein the dispersant for the disperse dye is at least The following (formula I)

[0009]

[Chemical 3]

(Where m = 1-5, n = 1-10, p =
0 to 12 and X ⁺ includes a dispersant represented by hydrogen ion, alkali metal ion or amine compound ion), and the surfactant is at least the following (formula II)

[0011]

[Chemical 4]

An ink composition comprising a surfactant represented by the formula (a + b = 0 to 30).

In the ink jet dyeing method of the present invention, the disperse dye dyeable cloth on which at least a cationic compound is adhered is subjected to ink jet printing using the above ink composition, and then the cloth is subjected to at least heat treatment. An inkjet dyeing method characterized by the above.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail below.

The ink composition of the present invention is basically composed of a component containing at least a disperse dye dispersed by a dispersant, a water-soluble organic solvent, a surfactant and water.

The most important component of the ink composition of the present invention is a disperse dye as a coloring component. The disperse dyes include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polylactic acid, polyesters such as copolymers or blends containing them as a main component, triacetate, nylon 6 or nylon 66.
It is a dye which is preferably sparingly water-soluble and is preferably used for dyeing polyamides such as C.I. I.
Although it is widely known under the name of Disperse, it is not limited thereto and can be used without any particular problem as long as it can dye the above polyester and the like. The disperse dye-dyed fabric referred to in the present invention means a woven fabric, a knitted fabric, a non-woven fabric or the like using fibers made of the above polyesters, acetates, polyamides and the like.

The average particle size of the disperse dye used in the present invention is preferably 0.05 to 0.5 μm, more preferably 0.05 to 0.4 μm, and most preferably 0.05 to 0.3 μm. Is. Average particle size is 0.5 μm
The larger particles mentioned above cause severe sedimentation and are not preferable.
If the average particle size is less than 0.05 μm, the viscosity of the ink composition tends to increase. As a method of making the particles of the disperse dye have such an average particle diameter, a coarse disperse dye is mixed with a dispersant described below, and a mill, a roll mill,
Coarse particles may be removed after finely pulverizing with a known pulverizing device such as a ball mill, a pearl mill, and a sand grinder to reach the above average particle diameter.

The concentration of the disperse dye in the ink composition of the present invention is a value which can be appropriately changed according to the color density to be expressed, but is preferably 0.05 to 20% by weight, and 0.1 to 1
5% by weight is more preferable, and 1 to 10% by weight is further preferable.

In addition to the disperse dye, the ink composition of the present invention requires water in which the disperse dye is dispersed in order to bring it into a liquid state as an ink, and it is necessary to secure the dispersion stability of the disperse dye. In order to stabilize the quality of the ink composition, ultrapure water produced by combining a reverse osmosis membrane and an ion exchange resin is preferably used.

One of the characteristics of the ink composition of the present invention is a dispersant for dispersing a disperse dye in water. The dispersant used in the present invention contains at least a dispersant represented by the following (formula I) as an essential component.

[0021]

[Chemical 5]

Here, m = 1 to 5, n = 1 to 10, p =
0 to 12 and X ⁺ are one selected from hydrogen ion, alkali metal ion, and amine compound ion.

As the dispersant having a high dispersion stabilizing effect, the optimum values of m, n and p can be changed depending on the kind of the disperse dye, so that the particularly preferable values of m, n and p can be unambiguously stated. Absent. However, when the ink composition of the present invention is dropped onto the cloth pretreated with the cationic substance, the dispersion destruction of the disperse dye efficiently occurs, and the bleeding of the dye is suppressed in a preferable range of m = 3 to 5 , N = 1 to 5, p =
It is 5-12. In addition, due to the production of the dispersant, m,
A distribution may occur in the values of n and p, but there is no particular problem as long as the value of the main component is in the above range.

Further, in the above (formula I), X ⁺ is one selected from hydrogen ion, alkali metal ion such as lithium ion, sodium ion and potassium ion, and amine compound ion such as triethanolamine.
Among them, sodium ion is preferable.

The concentration of the dispersant charged is preferably 10 to 100% by weight based on the disperse dye, and 15 to 50% by weight.
Is more preferable and 20 to 30 weight% is still more preferable.

Another feature of the ink composition of the present invention is that it contains a surfactant represented by the following (formula II).

[0027]

[Chemical 6]

Here, in order not to impair the dispersion stability, a
+ B = 0 to 30 is preferable. More preferably a + b = 0
10 to 10, more preferably a + b = 3 to 5.
It should be noted that there may be a distribution in the value of a + b or the ratio of a and b due to manufacturing reasons, but there is no particular problem as long as the value of the main component is in the above range.

The surfactant serves as an active ingredient for the dynamic surface tension described later and for suppressing the amount of bubbles generated when the ink is shaken and providing the defoaming property. In the ink composition, all of the above dispersants are not adsorbed on the disperse dye, but maintain a certain equilibrium concentration with respect to a mixed dispersion medium of water and a water-soluble organic solvent. It is the main factor of the ink surface tension. The discovery in the present invention is that the above-mentioned dispersant alone cannot satisfy the regulation for the dynamic surface tension described later, but by adding the present surfactant, the dispersant and the present interface are simply added. Rather than exhibiting an intermediate dynamic surface tension behavior with the activator,
It was found that the present surfactant was dominant, leading to the invention. Although it is possible to use the present surfactant as a dispersant for a disperse dye, in order to give a highly sharp inkjet print image to a cloth to which a cationic compound has been added, as will be described later. Of the anionic surfactants, the dispersant of the present invention is effective, and since the nonionic surfactant of the present invention does not act effectively, it is necessary to use both in combination.

The concentration of the surfactant in the ink composition is preferably 0.05 to 5% by weight, more preferably 0.1 to 3% by weight, and most preferably 0.5 to 2% by weight.
% By weight.

Further, to the ink composition of the present invention, a water-soluble organic solvent such as glycols, lower alkyl ethers of polyhydric alcohols, amines and pyrrolidones is added to prevent drying during use. It is necessary to have Among these, the hydroxyl group having 3 to 6 carbon atoms is 2
A compound having one or more compounds and being in a liquid state at room temperature is preferable from the viewpoint of dispersion stability of the disperse dye. Further, in order to suppress the sedimentation of the disperse dye, the specific gravity of the water-soluble organic solvent is
It is preferable that it is 1.1 to 1.3 at 20 ° C., for example, ethylene glycol (specific gravity 1.1).
2), diethylene glycol (the same 1.12), triethylene glycol (the same 1.13), tetraethylene glycol (the same 1.12), polyethylene glycol (the same 1.
12-1.20), glycerin (the same 1.26), and 2-pyrrolidone (the same 1.11) are preferably used. Among these, glycerin is preferably used because it has a particularly high precipitation suppressing effect.

The concentration of the water-soluble organic solvent in the ink is 10-
60 wt% is preferred, 15-50 wt% is more preferred, and 20-40 wt% is still more preferred.

Further, to the ink composition of the present invention, at least a compound obtained by formalin condensation of naphthalenesulfonate and naphthalenesulfonate having a hydroxyl group added is preferably added as a dispersant and / or a surfactant for a disperse dye. You can This compound is preferably used together when the disperse dye is dispersed with the dispersant of the above (formula I), but may be added after the above-mentioned essential components of the ink composition of the invention are prepared. It is also preferable to implement both. In any case, it contributes to the dispersion stability of the disperse dye. Although the detailed mechanism is unknown, when the ink composition using the dispersant of the above formula I can effectively suppress the bleeding on the cloth pretreated with the cationic compound, the dispersion stability of the disperse dye may be slightly increased. Tends to be low,
The addition of the condensation compound is preferable because it has both a high effect of suppressing bleeding and a high dispersion stability of the disperse dye.

When the disperse dye and the dispersant are mixed, the condensation compound is preferably added in an amount of 2 to 20% by weight, preferably 4 to 15% by weight, and preferably 6 to 10% by weight. Weight% is more preferred. When used as an additive to the ink composition, the concentration in the ink is
0.1 to 2% by weight is preferable, 0.3 to 1.5% by weight is more preferable, and 0.6 to 1.2% by weight is still more preferable.

The above-mentioned ink composition of the present invention is suitable for use in ink jet printing inks, especially ink jet dyeing inks.
If you do not set the pH properly, you will create unwanted drops when the ink is ejected from the inkjet head,
Various problems may occur, such as stains on the image, such abnormal droplets accumulating around the nozzles of the head that eject ink, and hindering ink ejection. The appropriate values of these values differ depending on the inkjet head, so it cannot be said unequivocally, but the viscosity is generally 10 × 10 ^-2 N
s / m ² or less, preferably 2 × 10 ^-2 to 4 × 10 ^-2 Ns
A / m ^2, whereas, for the surface tension, the static surface tension by measuring method represented by the ring method or the like 20 to 40
mN / m, preferably 25 to 35 mN / m.

In the present invention, these are also important physical properties, but in order to stably discharge for a long time, what is more important is a measuring method called a bubble pressure method or a maximum bubble pressure method. Dynamic surface tension at a bubble generation cycle of 10 Hz and 1 Hz measured at 30 ° C.
That is, the difference in the dynamic surface tension in is -3 to 3 mN / m. The difference is more preferably −2 to 2 mN /
m. In addition, these values are
e Pressure Tensiometer BP
2 (Bubble Pressure Tension Meter BP
Required in 2). Still more preferably, the difference between the dynamic surface tension and the static surface tension at a bubble generation cycle of 1 Hz is -10 to 10 mN / m, and more preferably -5 to 5 mN / m. . The ink composition of the present invention satisfies these requirements of dynamic surface tension for stable ejection over a long period of time.

Further, in the present invention, other known additives can be added as ink components. For example,
A pH adjusting agent, a preservative, a conductivity adjusting agent, a viscosity adjusting agent, a chelating agent and the like can be added.

An ink composition having the above-mentioned physical properties and having the composition of the present invention is generally used in an ink jet printing apparatus so that the ejection is intermittent and the ink circulation substantially causes a stirring action of the ink. It is particularly suitably applicable to an on-demand type inkjet printing apparatus which does not have such a mechanism. As the on-demand method, a thermal method that mainly uses a heating element and a piezo method that uses a piezoelectric element are widely known.
The ink composition of the present invention can be particularly preferably used in the piezo system.

Another aspect of the present invention is an ink jet dyeing method using the above ink composition, wherein the ink composition of the present invention is applied to a cloth which can be dyed with a disperse dye having at least a cationic compound attached thereto. Ink-jet printing is carried out using the same, and then the cloth is subjected to at least heat treatment to obtain a printed cloth having a highly sharp image.

The heat treatment method varies depending on the type of dye and cloth used, but a general method is appropriately selected from steaming treatment with superheated steam, heat treatment with hot water or hot water, dry heat treatment, and the like. And preferably using superheated steam to perform the coloring operation in an atmosphere of 150 ° C to 200 ° C. Thereafter, the cloth is washed with water by a post-treatment such as a soaping treatment, but not limited to this.

The cationic compound used in the present invention is preferably a compound selected from at least one selected from the group consisting of water-soluble metal salts and polycation compounds. More specifically, examples of the water-soluble metal salt include halogenated metal salts and organic acid salts of alkali metals or alkaline earth metals such as potassium chloride, calcium chloride, and barium chloride. Further, examples of the polycation compound include polymers or oligomers of various quaternary ammonium salts. Further, it is possible to use various natural or synthetic stable water-soluble polymer compounds in combination with these cationic compounds. As the water-soluble polymer compound, starch, carboxymethyl cellulose, methyl cellulose, cellulosic materials such as hydroxyethyl cellulose, sodium alginate, guar gum, tamarind gum, locust bean gum, polysaccharides such as gum arabic,
Examples of the synthetic water-soluble polymer compound include polyvinyl alcohol, polyvinylpyrrolidone, acrylic acid-based polymers and the like.

The cationic compound, the water-soluble polymer compound and the like may be attached to the cloth by a known technique such as a pad method, a coating method and a spray method. The applied amount should be appropriately selected according to the material, structure, structure, etc. of the cloth, but 0.2 to 50% by weight of the cationic compound adheres to the cloth before the application. It is preferably 0.5 to 25% by weight, more preferably 1 to 10% by weight.

[0043]

The present invention will be described in more detail with reference to the following examples. The present invention is not limited to the embodiments.

Example 1 First, a disperse dye and a dispersant were mixed according to the following formulation, and the mixture was ground with a sand grinder. Disperse dye base CIDisperse Yellow 114 20% by weight (formula I), m = 4, n = 4, p = 10, X ⁺ = Na ⁺ dispersant 5% by weight water 75% by weight Filtered, average particle size 0.3μm
To obtain a disperse dye.

Next, the ink composition of the present invention was prepared according to the following formulation.

Dispersant-containing disperse dye 2% by weight (formula II), a + b = 0 surfactant 1% by weight glycerin (specific gravity 1.26) 30% by weight water 67% by weight Surface of ink composition obtained The values related to tension were as follows. Difference in dynamic surface tension between 10 Hz and 1 Hz = 1.5 m
N / m 1Hz difference of dynamic surface tension and static surface tension = 4m
N / m The obtained ink composition was loaded into MJ-8000C manufactured by EPSON, which is an inkjet printing apparatus. A taffeta fabric made of polyethylene terephthalate fiber was prepared by applying a treatment liquid containing 3% by weight of calcium chloride as a cationic compound and 1.5% by weight of guar gum as a water-soluble polymer compound by a pad dry method. A test pattern was printed on this woven sheet.
Even when printing 1000 sheets including an operation such as stopping for 2 days, no ejection failure was observed and stable printing was possible. The dot diameter on the cloth was 0.14 mm, and a clear image could be obtained.

Comparative Example 1 An ink was prepared by removing the surfactant of the formula (II) from the formulation of the ink composition of Example 1. The values relating to the surface tension of the obtained ink composition were as follows. Difference in dynamic surface tension at 10 Hz and 1 Hz = 4 mN /
Difference between dynamic surface tension and static surface tension at m 1 Hz = 11
mN / m Using this ink composition, printing was carried out in the same manner as in Example 1. As a result, non-ejection became noticeable from around the 20th sheet of A4 paper.

Comparative Example 2 In the ink composition of Example 1, the nonionic polyoxyethylene-polyoxypropylene glycol dispersant ADEKA Pluronic (Asahi Denka Co., Ltd.) was used in place of the dispersant of the formula (I). Printing was performed in the same manner as in Example 1. as a result,
The dot diameter on the cloth was 0.29 mm, and the image was blurred and blurred. (Example 2) In the formulation of the ink composition of Example 1, an ink was prepared by using ethylene glycol having a specific gravity of 1.12 instead of glycerin having a specific gravity of 1.26. The value of the surface tension of the obtained ink was within the following range. Difference in dynamic surface tension between 10 Hz and 1 Hz = -2 mN
/ M Difference in dynamic surface tension and static surface tension at 1HZ = 6m
N / m Printing was performed by the same operation as in Example 1, and 1000 sheets could be printed even including the condition of stopping for 1 day. However, if the stoppage for 2 days or more is included, the probability of non-ejection increases.

Example 3 A disperse dye and a dispersant were mixed with each of the following disperse dye bases for each color ink, and the mixture was pulverized with a sand grinder. The formulations when the respective disperse dye raw materials and the dispersants are subjected to the sand grinder treatment are as follows. Disperse dye base 20 wt% (Formula I), m = 3, n = 5, p = 9, X ⁺ = Na ⁺ dispersant 5 wt% Kao Demol C 2 wt% Water 73 wt% Dispersion obtained The dye dispersion is filtered to give an average particle size of 0.3 μm.
To obtain a disperse dye. Next, the ink composition of the present invention was prepared according to the following formulation. In addition, the dye concentration was appropriately changed for each color ink so that the balance of the color densities upon color development was good. Along with this, the viscosity of the ink also changes depending on each dye, so the concentration of glycerin was also changed so that the viscosity of all inks was adjusted to be about the same. Dispersant-containing disperse dye 1 to 7% by weight (Formula II) a + b = 4 surfactant 1% by weight Glycerin (specific gravity 1.26) 20 to 40% by weight Water balance Regarding the surface tension of each ink obtained The values were within the following range. Difference in dynamic surface tension between 10 Hz and 1 Hz = 0.3 to
Difference between dynamic surface tension and static surface tension at 2 mN / m 1 Hz = -5
.About.4 mN / m These inks were loaded in an inkjet printer, FJ-600 manufactured by Roland DG. At this time, the ink tank of the inkjet printing apparatus was improved so that it could be loaded with a funnel so that the ink could be easily loaded. However, when the ink was loaded, the above-mentioned ink disappeared immediately even if bubbles were generated.

A woven fabric (width: 1.3 m) made of polyethylene terephthalate fiber, which is lined with paper to give rigidity, calcium chloride which is a cationic compound and guar gum which is a water-soluble polymer are applied by a pad dry method. Solid pictures and various patterns were printed over 50 m. as a result,
No ejection failure was observed. Then, the woven cloth is 80
After performing preliminary drying at ℃, a coloring operation was performed in a superheated steam atmosphere at 175 ° C. After that, the cationic compound of the woven fabric was washed away by washing with hot water and washing with water. As a result, it was possible to obtain a high-quality textile printing cloth without blurring, in which the fine lines and the boundary between the color and another color were also sharply expressed.

Comparative Example 3 In the formulation of the ink composition in Example 3, instead of the surfactant of formula (II),
An appropriate amount of sodium dioctyl sulfosuccinate was added.
The value of the surface tension of the obtained ink was in the following range. Difference in dynamic surface tension between 10 Hz and 1 Hz = 2 mN /
Difference between dynamic surface tension and static surface tension at m 1 Hz = -5
Any value of mN / m is within the range defined by the present invention.

However, when the ink was loaded into the ink jet printing apparatus FJ-600 having the improved ink tank, a large amount of bubbles were generated. Printing was started after waiting until the bubbles appeared to disappear visually, but ejection failure occurred immediately, probably because of the inclusion of fine bubbles.

[0053]

EFFECTS OF THE INVENTION According to the present invention, it is possible to simultaneously provide long-term storage stability of ink, bubble breaking property, long-term ejection stability, and high-definition dyed image, which are important when ink-jet dyeing a disperse dye-dyed fabric. An ink composition that can be obtained is obtained.

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) D06P 5/00 111 D06P 5/20 A 5/20 B41J 3/04 101Y F term (reference) 2C056 FA04 FC02 2H086 BA01 BA02 BA05 BA22 BA52 BA53 BA56 BA59 BA60 4H057 BA08 CA12 CA13 CB21 CB27 CC02 DA01 DA34 FA17 GA06 HA01 JA10 JB03 4J039 AE07 BC09 BC54 BE08 BE12 BE22 CA06

Claims (8)

[Claims] 1. An ink composition containing at least a disperse dye dispersed by a dispersant, a water-soluble organic solvent, a surfactant and water, wherein the dispersant for the disperse dye is at least the following (formula I): ] (In the formula, m = 1 to 5, n = 1 to 10, p = 0 to 12, X
⁺ Contains a dispersant represented by one selected from hydrogen ion, alkali metal ion and amine compound ion), and the surfactant is at least the following (formula II): An ink composition comprising a surfactant represented by the formula (a + b = 0-30). 2. The dispersant and / or the surfactant of the disperse dye comprises at least a compound obtained by formalin condensation of naphthalene sulfonate and naphthalene sulfonate having a hydroxyl group added. Ink composition. 3. The average particle size of the disperse dye is from 0.05 to
The ink composition according to claim 1, which has a thickness of 0.5 μm. 4. The specific gravity of the water-soluble organic solvent is 1.1 to 1.3 at 20 ° C.
The ink composition according to any one of 3 above. 5. Dynamic surface tension at 10 Hz and 1H
The ink composition according to any one of claims 1 to 4, wherein the difference in dynamic surface tension in z is -3 to 3 mN / m. 6. The ink composition according to claim 1, wherein a difference between the dynamic surface tension at 1 Hz and the static surface tension is −10 to 10 mN / m. 7. The ink composition according to claim 1, which is used in an on-demand inkjet printing apparatus. 8. An ink jet print using the ink composition according to claim 1 on a disperse dye dyeable fabric having at least a cationic compound attached thereto.
Then, the inkjet dyeing method, wherein the cloth is subjected to at least heat treatment.