JPH0657188A - Ink for jet printer - Google Patents

Abstract

PURPOSE:To improve the adhesion of the jet printer ink to a substrate by incorporating a colorant, a resin, an electrolyte complex of 2-hydroxycarboxylic acid, and an org. solvent into the ink. CONSTITUTION:The This ink is prepd. by dissolving a binder resin, a colorant, 0.1-10.0wt.% electrolyte complex of 2-hydroxycarboxylic acid of the formula (wherein M is an element of the group IIIB, IVA, VIA, or VIIIA; R<1> to R<4> are each an alkyl, H, or aryl; and X<+> is an inorg. or org. cation), and 0.5-5wt.% plasticizer in an org. solvent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink for jet printers having excellent adhesion to various recording materials such as glass, metal and plastic.

[0002]

2. Description of the Related Art Printing by a jet printer is a method in which ink is ejected from a nozzle to adhere to a recording material. Since the nozzle and the recording material are not in contact with each other, a curved surface or an irregular shape with irregularities is formed. Good printing can be performed on the surface having the same.

Although various types of jet printers have been put to practical use as such jet printers, continuous type (charge control type) printers are mainly used in the marking field requiring high-speed printing. In this method, the ejected ink particles are charged according to an electrical character signal, and are deflected according to the amount of charge by a deflection electrode to form characters or the like, and it is necessary to impart conductivity to the ink. Therefore, various conductivity-imparting agents have been proposed. For example, JP-A-55-50073 and JP-A-5-50073
6-161480, JP-A 58-176271, JP-A 1-245071, and JP-B 2-45.
In Japanese Patent No. 663, there is proposed an ink using an inorganic salt such as sodium thiocyanate, ammonium thiocyanate or lithium nitrate as a conductivity-imparting agent, which is disclosed in Japanese Patent Laid-Open Nos. 56-36559 and 59-59. No. 202274 and JP-A-60-110770 propose inks using a hydrochloride of an organic amine as a conductivity-imparting agent. JP-A-62-109870 discloses
An ink using a quaternary ammonium salt of nitric acid or a quaternary ammonium salt of thiocyanic acid as a conductivity-imparting agent has been proposed.

[0004]

However, all of the inks described in the above publications have an appropriate electric conductivity, but the compatibility between the resin used as the binder and the conductivity-imparting agent is poor. Therefore, there is a problem that the adhesion to various recording materials is insufficient.

The problem to be solved by the present invention is to provide a jet having excellent adhesion to various recording materials such as glass, metal and plastic by using a conductivity-imparting agent having good compatibility with various resins. Providing ink for printers.

[0006]

Means for Solving the Problems As a result of intensive studies for solving the above-mentioned problems, the present inventors have found that the ink contains an electrolyte complex of 2-hydroxycarboxylic acid as a conductivity-imparting agent. Marking ink for jet printers that can provide appropriate electric conductivity and has excellent compatibility with the above-mentioned conductivity-imparting agent and various resins used as binders, and has excellent adhesion to various recording materials. It was found that they could be obtained, and the present invention was completed.

That is, in order to solve the above problems, the present invention provides a jet printer ink containing a colorant, a resin and an organic solvent, which contains an electrolyte complex of 2-hydroxycarboxylic acid as a conductivity-imparting agent. A featured jet printer ink is provided.

Next, the present invention will be described in detail.

Used as a conductivity-imparting agent in the present invention 2-
The electrolyte complex of hydroxycarboxylic acid has the general formula (I)

[0010]

[Chemical 1]

The compound represented by: is preferred. In the formula, M
Represents a Group IIIB element such as Al or B, a Group IVA element such as Ti, a Group VIA element such as Cr, or a Group VIII element such as Fe or Co, and R ¹ , R ² , R ³ and R ⁴ are each Independently, it represents hydrogen, an alkyl group such as a methyl group, an ethyl group or an n-butyl group, or an aromatic ring such as a benzene ring or a naphthalene ring. X ⁺ is Li ⁺ , Na ⁺ , K ⁺ , Mg ²⁺ , C
It represents an inorganic cation such as a ²⁺ and Zn ²⁺ , and an organic cation such as ammonium ion, iminium ion and phosphonium ion.

Specific examples of the compound represented by the general formula (I) are shown below, but these compounds can be used alone or in combination of two or more kinds. In addition, the content of these conductivity-imparting agents is preferably in the range of 1.0 to 10.0% from the viewpoint of providing the ink with appropriate electric conductivity.

[0013]

[Chemical 2]

[0014]

[Chemical 3]

[0015]

[Chemical 4]

[0016]

[Chemical 5]

[0017]

[Chemical 6]

[0018]

[Chemical 7]

[0019]

[Chemical 8]

[0020]

[Chemical 9]

The solvent that can be used in the present invention is not particularly limited as long as it can dissolve the dye as the colorant used in the present invention, the binder resin, and the conductivity-imparting agent. , Aliphatic alcohols such as ethanol and propanol, ketones such as dimethyl ketone and methyl ethyl ketone, glycols, glycol ethers, glycol esters, aromatic hydrocarbons, aliphatic hydrocarbons, amides, amino alcohols, Examples thereof include nitrogen-containing compounds such as morpholine and pyridine, and it is also possible to use two or more kinds in combination.
In particular, a solvent containing methyl ethyl ketone or methanol or ethanol is preferable as the solvent for improving the solubility of the conductivity-imparting agent, the electric conductivity of the ink, and the ink drying characteristics.

The binder resin used in the present invention can be used without particular limitation as long as it is soluble in the organic solvent and has a good compatibility with the conductivity-imparting agent. Specifically, acrylic resin, styrene acrylic resin, silicone resin, phenol resin, terpene phenol resin,
Epoxy resin, modified epoxy resin, polyester resin,
Examples thereof include cellulose resins, vinyl chloride-based resins, petroleum resins, rosin esters, and the like, but the present invention is not limited to these, and two or more types can be mixed and used at the same time.

The colorant used in the present invention is a monoazo type, disazo type, metal complex salt type, anthraquinone type, phthalocyanine type or triallylmethane type oil-soluble dye or carbon which has been conventionally used in various coloring fields. Examples thereof include, but are not limited to, inorganic pigments such as black, titanium oxide, zinc oxide, and zinc sulfide, and organic pigments such as monoazo pigments, disazo pigments, phthalocyanine pigments, and quinacridone pigments.

In order to improve the adhesion and the abrasion resistance at low temperature of the ink film printed with the marking ink for jet printer of the present invention, phthalate ester is added to the ink.
A compound having good compatibility with the binder resin used in the present invention, which is a plasticizer such as sebacic acid ester, stearic acid ester, phosphoric acid ester, citric acid ester, adipic acid ester, maleic acid ester, trimellitic acid ester, etc. It is preferable to add 0.5 to 5% by weight of at least one compound selected from the group consisting of phthalic acid ester and sebacic acid ester, which has good compatibility with the resin used in the present invention. preferable.

Examples of the phthalic acid ester include diethyl phthalate, dibutyl phthalate, dioctyl phthalate and the like, and examples of the sebacate ester include diethyl sebacate, dibutyl sebacate and dioctyl sebacate. Is not limited to these.

[0026]

The present invention will be described in detail below with reference to examples. In addition, "part" in the following examples and comparative examples represents "part by weight".

Example 1 C.I. I. Solvent Blue 70 7.0 parts "Dianal BR-113" (acrylic resin manufactured by Mitsubishi Rayon Co., Ltd.) 4.5 parts "XJ-6007" (modified epoxy resin manufactured by Ciba-Geigy Japan) 6.0 parts "KR-216" ( Shin-Etsu Silicone Co., Ltd. silicone resin) 3.5 parts Dibutyl sebacate 1.5 parts Compound of formula (1) 3.0 parts Methyl ethyl ketone 60.5 parts Methanol 14.0 parts

After thoroughly stirring and dissolving the above composition,
This solution was filtered using a 0.5 μm membrane filter to obtain a marking ink for a jet printer.

Example 2 C.I. I. Solvent Red 35 3.0 parts "John Cryl 611" (Styrene acrylic resin manufactured by Johnson Polymer Co., Ltd.) 16.0 parts "YS Polystar T-130" (terpene phenol resin manufactured by Yasuhara Chemical Co., Ltd.) 7.0 parts Dibutyl sebacate 2. 0 part Compound of formula (2) 3.0 parts Methyl ethyl ketone 55.0 parts Methanol 14.0 parts

After thoroughly stirring and dissolving the above formulation,
This solution was filtered using a 0.5 μm membrane filter to obtain a marking ink for a jet printer.

Example 3 C.I. I. Solvent Yellow 79 5.0 parts "NCL1 / 8" (nitrocellulose resin manufactured by Asahi Kasei Corp.) 16.0 parts Dibutyl phthalate 2.0 parts Compound of formula (4) 3.0 parts Methyl ethyl ketone 56.0 parts Methanol 18.0 Department

After thoroughly stirring and dissolving the above formulation,
This solution was filtered using a 0.5 μm membrane filter to obtain a marking ink for a jet printer.

(Example 4) C.I. I. Solvent Blue 70 3.0 parts C.I. I. Solvent Yellow 79 4.0 parts "Dianal BR-113" 6.0 parts "XJ-6007" 6.0 parts Dibutyl phthalate 2.0 parts Compound of formula (6) 3.5 parts Methyl ethyl ketone 55.5 parts Methanol 15.0 parts Ethanol 5.0 parts

After thoroughly stirring and dissolving the above formulation,
This solution was filtered using a 0.5 μm membrane filter to obtain a marking ink for a jet printer.

(Example 5) "REGAL 99R" (carbon black manufactured by CABOT) 4.0 parts "VROH" (hydroxyl-modified vinyl chloride vinyl acetate copolymer resin manufactured by Union Carbide) 4.0 parts Solspers 2400 ( ICI CI Pigment Dispersant) 0.4 part Solspers 5000 (ICI Pigment Dispersant) 0.1 part Dibutyl Sebacate 1.0 part

3.0 parts of "VMCA" (carboxyl-modified vinyl chloride vinyl acetate copolymer resin manufactured by Union Carbide Co.) was added to 9.5 parts of chips obtained by kneading and dispersing the above-mentioned compound by a two-roll mill, and the formula (1) was used. A solution prepared by dissolving 2.0 parts of the compound of Example 1 in 85.5 parts of methyl ethyl ketone was added, and after sufficiently stirring, the mixed solution was filtered using a 5μ filter to obtain a marking ink for a jet printer.

(Example 6) "R-830" (Rutile type titanium oxide manufactured by Ishihara Sangyo Co., Ltd.) 8.0 parts "John Cryl 611" 8.0 parts "Solspurs 2400" 1.6 parts Methyl ethyl ketone 34.0 parts

The above composition was dispersed in a paint conditioner for 2 hours to prepare a base ink, "John Cryl 6".
11 "10.0 parts," ester gum HT "(Arakawa Chemical Co., Ltd. rosin ester) 6.0 parts, compound of formula (1) 4.0
Parts of methyl ethyl ketone 9.4 parts and methanol 19.0
After adding a solution dissolved in a part of the mixed solvent and stirring the mixture sufficiently, this mixed solution was filtered using a 5μ filter to obtain a marking ink for a jet printer.

Using the inks of Examples 1 to 6, a glass plate, a plastic plate (acrylic resin, nylon resin, vinyl chloride resin, polycarbonate resin) manufactured by Hitachi Ltd. using a continuous ink jet printer "IJ Printer" ), And printed on a metal plate (aluminum, stainless steel, tin plate). As a result, a clear printed image was obtained on glass acrylic resin, nylon resin, vinyl chloride resin, polycarbonate resin, aluminum, stainless steel, and tin plate, and jetting stability was also good.

Next, "cellophane tape" (cellophane adhesive tape manufactured by Nichiban Co., Ltd.) was adhered to each printed image printed on the above-mentioned printed matter, and then the "cellophane tape" was peeled off to evaluate the adhesion of the printed image. Then, the printed image is erased with an eraser (MONO manufactured by Tombow Pencil Co., Ltd.)
When the adhesion of the printed image by rubbing was evaluated, it was sufficiently readable and had good adhesion.

Further, when the water resistance of the printed image was evaluated by immersing the printed material on the glass plate in water for 1 hour, it was found that the printed image did not peel and was sufficiently readable.

(Comparative Example 1) C.I. I. Solvent Blue 70 7.0 parts "Dianal BR113" 4.5 parts "XJ-6007" 6.0 parts "KR-216" 3.5 parts Dibutyl sebacate 1.5 parts Sodium thiocyanate 0.5 parts Methyl ethyl ketone 60 .5 parts methanol 16.5 parts

The above formulation using sodium thiocyanate instead of the compound of formula (1) in the ink composition of Example 1 was thoroughly stirred and dissolved, and then this solution was added to 0.5 μm.
A marking ink for a jet printer was obtained by filtration using a membrane filter.

(Comparative Example 2) "R-830" 8.0 parts "John Cryl 611" 8.0 parts "Solspers 2400" 1.6 parts Methyl ethyl ketone 34.0 parts

To the base ink prepared by dispersing the above-mentioned composition for 2 hours with a paint conditioner, 10.0 parts of "John Cryl 611", 6.0 parts of "Ester gum HT" (rosin ester manufactured by Arakawa Chemical Co., Ltd.), and lithium nitrate of 0. A solution prepared by dissolving 5 parts in a mixed solvent of 12.9 parts of methyl ethyl ketone and 19.0 parts of methanol was added, and after sufficiently stirring,
This mixed solution was filtered using a 5μ filter to obtain a marking ink for a jet printer using lithium nitrate instead of the compound of formula (1) in the ink composition of Example 6.

Using the inks of Comparative Examples 1 and 2, glass plates, plastic plates (acrylic resin, nylon resin, vinyl chloride resin, polycarbonate resin), metal plates (aluminum, stainless steel, tin plate) were used in the same manner as in Example 1. ) Was printed. As a result, a clear printed image was obtained on glass acrylic resin, nylon resin, vinyl chloride resin, polycarbonate resin, aluminum, stainless steel, and tin plate, and jetting stability was also good.

Next, "cellophane tape" (cellophane adhesive tape manufactured by Nichiban Co., Ltd.) was attached to each printed image printed on the above-mentioned printed matter, and then the "cellophane tape" was peeled off to evaluate the adhesion of the printed image. Then, the printed image is erased with an eraser (MONO manufactured by Tombow Pencil Co., Ltd.)
When the adhesion of the printed image by rubbing was evaluated,
Peeling was observed in part of the printed image.

Furthermore, when the printed image on the glass plate was immersed in water for 1 hour to evaluate the water resistance of the printed image, the printed image peeled and became unreadable.

[0049]

INDUSTRIAL APPLICABILITY According to the present invention, in a jet printer ink containing a colorant, a resin, and an organic solvent, glass, metal, It is possible to obtain an ink having excellent adhesion to various recording materials such as plastics and having good jetting stability.

Claims (1)

[Claims] 1. An ink for a jet printer containing a colorant, a resin, and an organic solvent, which contains an electrolyte complex of 2-hydroxycarboxylic acid.