JPH06240194A - Ink composition for ink jet printing - Google Patents

Abstract

PURPOSE:To obtain an ink composition excellent in long-term dispersion stability and the ink jet printability for hydrophobic textiles, and capable of giving printed products of clear red color by containing a disperse dye of specific structure. CONSTITUTION:This ink composition contains pref. 2-20wt.% of a disperse dye of the formula (R is 1-4C alkyl, phenyl, etc.) based on the whole amount of the final ink liquid composition. Besides the disperse dye, the composition is pref. incorporated with water, a hydrophilic organic solvent such as polyethylene glycol and anionic surfactant (e.g. lignin sulfonate) and/or nonionic surfactant (e.g. ethylene oxide of alkylphenol). To prepare this composition as an ink for ink jet use, it is recommended that surfactant(s) and water be added to the disperse dye of the formula followed by wet grinding so as to have <=0.5mum particle diameter of the dye and diluting the resultant particles with water and the hydrophilic organic solvent, and then, if necessary, carrying out filtration.

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 inkjet printing. In particular, the present invention relates to an ink composition for inkjet printing, which is suitable for printing a woven or non-woven fabric made of hydrophobic fibers such as polyester and acetate, or a mixed woven fabric made of these fibers and other fibers.

[0002]

2. Description of the Related Art Conventionally, a so-called ink jet printing method has been known in which ink droplets are ejected from minute ejection orifices for printing. Various legal formulas have been proposed for such a printing method. For example, a method of giving a signal to a printer head having a piezo-vibrator to generate ink droplets according to the signal for printing, or electrostatically sucking ink and controlling the generated droplets by an electric field according to the signal. However, there are many types such as those for printing, those for generating droplets whose charge amount is controlled by the continuous vibration generation method, and flying these droplets between deflection electrodes to which a uniform electric field is applied for printing. The scheme is known.

Such an ink jet printing system is
Ink droplets are ejected and the ink droplets are attached to a material to be dyed for printing. Such an ink contains a coloring material and a liquid medium in which the coloring material is dispersed (water, various organic solvents, or a mixture thereof) as a basic component, and may contain various additives as necessary.

The preferable conditions for this type of ink are:
Does not clog the discharge orifice, has liquid properties suitable for discharge (viscosity, surface tension, conductivity, etc.), does not change physical properties or solids during storage, and has a high concentration To give fast fixing to the material to be dyed, little ink bleeding, excellent water resistance and light resistance, little odor and toxicity, and excellent safety such as flammability, etc. Is mentioned.

Since the ink applied to the print for such a purpose is basically composed of a dye and its solvent as described above, the characteristics of the above ink are unique to the components used as the dye and the liquid medium. It greatly depends on the nature of. Therefore, it is a very important technique in the technical field to select the dye and the liquid medium so that the ink has the above characteristics.

[0006] Furthermore, it is a recent social demand from the environmental aspect that the BOD and COD loads of the wastewater after dyeing are reduced. Although the ink jet printing method has made it possible to greatly reduce the printing paste, it is desirable that the ink side itself has a small drainage load. That is, it is desired that the amount of various additives added is small and the dye has a high concentration and good storage stability over a long period of time. From this aspect as well, it is an increasingly important technique to select a dye and a liquid medium. .

In ink jet printing, the three primary colors (yellow, red and blue) are usually required to have clear hues. Further, the dye used for printing on the fiber is required to have excellent dyeing properties such as dyeing reproducibility, various fastnesses, and white spot stain resistance.

From this point of view, ink jet printing inks using disperse dyes have been proposed. For example, a disperse dye dissolved in an organic solvent (Japanese Patent Publication No. 54-217).
66, JP-A-60-75693), or a type in which a disperse dye is dispersed in water (JP-A-60-7).
5692, 60-133076, Japanese Patent Publication 6
2-57750, JP-A-4-33309, etc.) and the like.

However, the dissolution type ink has a low solubility of the disperse dye and it is difficult to produce an ink composition having a high dye concentration, and the dispersion type ink composition is still a problem in terms of dispersion stability. Is not resolved.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to provide an ink composition for inkjet printing, which is excellent in dispersion stability for a long period of time, is suitable for inkjet printing, and is clear and has excellent dyeing properties. .

[0011]

The present inventors have accomplished the present invention as a result of intensive studies to solve the above-mentioned problems. That is, the present invention uses the formula (1)

[0012]

[Chemical 2]

(Wherein R is an alkyl group, an alkoxyalkyl group, an alkoxyalkoxyalkyl group, a phenylalkyl group, a phenoxyalkyl group, a phenylalkoxyalkyl group, a phenylalkoxyphenyl group, a phenoxyalkoxyphenyl group or a hydroxy group, a chlorine atom,
It represents a phenyl group which may be substituted with a bromine atom, an alkyl group or an alkoxy group. Here, the alkyl group and the alkoxy group are those having 1 to 4 carbon atoms. ) An ink composition for inkjet printing containing at least one of the disperse dyes represented by the formula (1), preferably at least one of the disperse dyes of the formula (1), water, a hydrophilic organic solvent, an anionic surfactant and / or a nonionic interface. An ink composition for inkjet printing, which comprises an activator.

The dyes represented by the above formula (1) used in the present invention are known from JP-B-38-8498 and 39-5967. The dyes of formula (1) are known to dye hydrophobic fibers, for example polyethylene terephthalate fibers, in a bright red color.

In the ink composition of the present invention, the disperse dye represented by the formula (1) is used in an amount of 1 to 30% by weight, preferably 2 to 20% by weight based on the total weight of the ink liquid. .

A liquid medium containing water and a hydrophilic organic solvent is used as the liquid medium of the ink composition of the present invention. Here, the hydrophilic organic solvent has an effect as a non-drying agent, has a role of preventing the generation of solid matter by drying, and also has a role of adjusting the viscosity of the ink composition.

As the hydrophilic solvent, polyalkylene glycols such as polyethylene glycol and polypropylene glycol; alkylene glycols such as ethylene glycol, propylene glycol and butylene glycol; glycerin; N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, etc. One or more of the nitrogen-containing heterocyclic ketones and the like can be used as the liquid medium component.

The content of the hydrophilic organic solvent in the ink composition is generally 1 to 50% by weight, preferably 2 to 20% by weight based on the total weight of the ink liquid.

Specific examples of the anionic surfactant used in the present invention include lignin sulfonates, formalin condensates of naphthalene sulfonates, formalin condensates of alkylnaphthalene sulfonates, and special aromatic sulfonic acids. Examples thereof include formalin condensates of salts. Examples of the nonionic surfactants include block copolymers of ethylene oxide and propylene oxide, ethylene oxide adducts of alkylphenols, ethylene oxide adducts of mono- or distyrenated phenols, and the like.

The above-mentioned surfactants can be used alone or in a mixture. The amount used is in the range of 3 to 50% by weight, preferably 5 to 25% by weight, based on the total weight of the ink composition.

In order to apply the ink composition of the present invention to the ink jet system, one or a mixture of the above surfactants and water are added to the disperse dye represented by the above formula (1) and the mixture is mixed with a ball mill or a sand mill. Sufficiently wet-milling to make the particle size of the dye 5 μm or less, preferably 0.5 μm or less, and diluting to a desired dye concentration with water and a hydrophilic organic agent, and then dye or dust having a large particle size. If necessary, foreign matter is removed by passing it through a filter before use.

The ink composition for ink-jet printing of the present invention thus prepared is characterized in that it is particularly excellent in stability and long-term storability among various characteristics and does not clog the discharge orifice. When a bactericidal or antifungal agent (for example, Deltop manufactured by Takeda Pharmaceutical Co., Ltd.) is added, it may be added before the filtration.

[0023]

EXAMPLES The present invention will be specifically described with reference to examples.
The invention is not limited to only these examples.
In the examples,% and parts are based on weight.

Example 1 The following formula (2) obtained by synthesis by a known method

[0025]

[Chemical 3] In the presence of 100 parts by volume of glass beads, 18 parts of the disperse dye raw material, 12 parts of formalin condensate of sodium naphthalene sulfonate, 6 parts of sodium lignin sulfonate and 53 parts of water are wet pulverized in a sand mill for 24 hours to obtain fine particles. Turned into The glass beads were removed by filtration to obtain 60 parts of a dispersion liquid. 0.8 parts of a block copolymer of ethylene oxide and propylene oxide, 6.9 parts of glycerin and 53 parts of water were added thereto to obtain an ink composition having a dye concentration of 10%.
This was further passed through a 10-micron filter to remove large dye particles, foreign matters and the like to obtain a 10% ink composition having an average particle diameter of 0.1 micron for inkjet printing.

The ink composition for ink jet printing obtained in this example showed good stability at room temperature or low temperature (0 degree Celsius) without aggregation or precipitation for more than one month.

Using the inks obtained according to the above examples,
The pretreated polyethylene terephthalate fiber was printed with an on-demand type ink jet printer, dried at 80 ° C., held in superheated steam at 170 ° C. for 7 minutes, washed with water, reduced, washed with water, and dried. A dyed product in which the printed portion was colored in a clear red color was obtained. This was a beautiful dyed product without any bleeding.

Example 2 The following formulas (3) and (4) obtained by synthesis in the same manner as in Example 1

[0029]

[Chemical 4] 17 parts of a 1: 1 mixture of the disperse dyes represented by the formula 1, 11 parts of a formalin condensate of sodium naphthalene sulfonate, 7 parts of sodium lignin sulfonate and 60 parts of water and 100 parts of glass beads.
Wet grinding was carried out for 36 hours in a sand mill in the presence of a capacity part to form fine particles. Glass beads are removed by filtration and dispersion 68
I got a part. To this, 1 part of a block copolymer of ethylene oxide and propylene oxide, 6 parts of ethylene glycol and 77.5 parts of ion-exchanged water were added, and the average particle size was 0.1.
An 8% micron ink composition was obtained.

The ink composition for ink jet printing obtained in this example showed good stability at room temperature or low temperature (0 degree Celsius) without aggregation or precipitation for more than 1 month.

Using the inks obtained according to the above examples,
The pretreated polyethylene terephthalate fiber was printed with an on-demand type ink jet printer, dried at 80 ° C., held in superheated steam at 170 ° C. for 7 minutes, washed with water, reduced, washed with water, and dried. A dyed product in which the printed portion was colored in a clear red color was obtained. This was a beautiful dyed product without any bleeding.

Examples 3 to 15 The following formula (5) is obtained by a known method.

[0033]

[Chemical 5] And an R having the structure as shown in the following table are synthesized, an ink composition is prepared in the same manner as in Example 1 or 2, and these inks are used in an on-demand type ink jet printer. As a result, it is possible to obtain a dyed product which is printed on a polyester fiber which has been subjected to pretreatment, and which has a bright red color without any bleeding.

Example R 3 C ₂ H ₅ 4 C ₄ H ₉ 5 C ₂ H ₄ OCH ₃ 6 C ₂ H ₄ OC ₄ H ₉ 7 C ₂ H ₄ OC ₂ H ₄ OCH ₃ 8 C ₂ H ₄ OC _{2 H 4 OC 4 H 9 9 C} 2 H 4 OPh, the C ₂ H ₄ Ph 1:
1 mixture 10 C ₂ H ₄ OCH ₂ Ph 11 Ph 12 Ph-4-OH 13 Ph-4-Cl 14 Ph-4-OCH ₃ 15 Ph-4-Br (where Ph is a phenyl group and Ph-4- The substituent means that a substituent is introduced at the 4-position of the phenyl group.)

[0035]

EFFECT OF THE INVENTION A useful ink composition having excellent dispersion stability even after being stored for a long period of time, excellent in ink jet printing suitability for hydrophobic fibers, and giving a clear red printed material was obtained.

Claims (3)

[Claims] 1. An ink composition for inkjet printing, which comprises at least one of the disperse dyes represented by the general formula (1) and is used for hydrophobic fibers. [Chemical 1] (In the formula, R is an alkyl group, an alkoxyalkyl group, an alkoxyalkoxyalkyl group, a phenylalkyl group, a phenoxyalkyl group, a phenylalkoxyalkyl group, a phenylalkoxyphenyl group, a phenoxyalkoxyphenyl group or a hydroxy group, a chlorine atom, a bromine atom, an alkyl group. Represents a phenyl group which may be substituted with a group or an alkoxy group, wherein the alkyl group and the alkoxy group are those having 1 to 4 carbon atoms.) 2. A water-soluble organic solvent containing water and a hydrophilic organic solvent.
The ink composition for inkjet printing according to item 4. 3. The ink composition for inkjet printing according to claim 1, which contains an anionic surfactant and / or a nonionic surfactant.