JPH02276870A - Ink composition for jet printers - Google Patents

Abstract

PURPOSE:To provide an ink composition capable of being printed on the surfaces of various articles, especially articles containing waxes, and used for jet printers by incorporating an oil-soluble dye, a wax-compatible resin and an organic solvent. CONSTITUTION:The objective composition comprises (A) an oil-soluble dye, preferably a metal-containing dye, (B) a wax-compatible resin, preferably a terpene phenol resin, and (C) an organic solvent, preferably methylethyl ketone, methanol or ethanol. The component A is preferably used in an amount of 0.1-15wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an ink composition for jet printers that is capable of printing on various recording media, particularly on surfaces containing wax.

[Conventional technology]

Printing with a jet printer is a method in which the injected ink is attached to the recording medium, and printing is possible without contact between the coating machine and the recording medium, and it is especially useful for printing on irregularly shaped surfaces. It is suitable.

Various types of ink for jet printers are known. For example, Japanese Patent Application Laid-open No. 56-36559 describes an ink with excellent anti-fading properties, abrasion resistance, and light resistance, including epoxy-phenol resin, Inks containing solvents and dyes have been proposed.

Further, Japanese Patent Laid-Open No. 161480/1983 proposes an ink that can be used regardless of the material of the recording medium to be printed. This ink contains a solvent whose main components are ketones, alcohol, and water, dyes, ionizable salts, surfactants, and resins, and is characterized by the use of nonionic surfactants. be.

In addition, Japanese Patent Application Laid-open No. 59-202274 describes the density of base materials such as paper, metal, glass, rubber, etc. As an ink with improved properties, phenolic resol resin, ketone,
゛? An ink containing a solvent based on alcohol and water, a dye, and an organic amine salt has been proposed.

In addition, JP-A No. 62-109870 describes an ink that does not corrode the metal of the coater and has excellent adhesion to recording materials coated with wax, which contains quaternary ammonium salt as a conductivity imparting agent. An ink that does this has been proposed.

[Problems to be Solved by the Invention] However, since the inks described in the above publications contain electrolytes (ionizable salts) in the ink composition, electrolytes precipitate in the ink film of printed matter using these inks. Since it is easy to use, its strength tends to be low. For example, it is difficult to obtain sufficient adhesion to recording materials coated with wax.

An object of the present invention is to provide an ink composition for jet printers that not only has excellent light resistance, abrasion resistance, jetting stability, etc., but also has excellent adhesion to recording materials coated with wax. It is.

[Means to solve the problem]

In order to solve the above-mentioned problems, the present inventors have made extensive studies and found that it is possible to impart appropriate electrical conductivity without adding electrolyte (ionic salts), and stable injection is possible. The present invention was developed in an effort to obtain an ink for a lift printer that has excellent adhesion to a recording medium, especially a surface coated with wax.

As a result, using a resin with good compatibility with wax has excellent adhesion to the wax-coated surface, and it is also recommended to use ionizable salts for ink used in the inkjet method called the continuous method. However, by using metal-containing dyes as oil-soluble dyes, appropriate electrical conductivity can be obtained, which combined with the fact that there is no need to use substances that would impair the adhesion, has led to the discovery that the above-mentioned adhesion can be further improved. Ta.

That is, the present invention provides an ink composition for jet printers containing an oil-soluble dye, a resin, and an organic solvent,
The present invention provides an ink composition for a jet printer, characterized in that the resin component contains a resin having good compatibility with wax. Examples of resins that have good compatibility with wax include terpene phenol resins, which are
It is also preferable that the oil-soluble dye is a metal-containing dye and the content is within the range of 0.1-15% by weight, and the organic solvent contains methyl ethyl ketone, methanol or ethanol. It is also preferable to do so.

Next, the present invention will be explained in detail.

As the oil-soluble dye used in the present invention, any dye can be used as long as it is soluble in the ink composition, but the following metal-containing dyes are particularly preferred.

C, r, 5olvent Black 22, 23, 2
7.29,34,43,47,123C,1,5olv
ent Yellosv 19.21+32+f;1
,79+80.81+820.1.5olvent R
ed 8, 35, 83, 84, 100, 109, 1) 8
,1)9゜121,122.160 C,1,5olvent Blue 25+55+70
However, the invention is not limited to these, and two or more oil-soluble dyes can be used in combination at the same time.

The content of these oil-soluble metal-containing dyes in the ink composition is 0.1 to 1 from the viewpoint of obtaining appropriate electrical conductivity of the ink.
A range of 5% by weight is preferred.

In the present invention, resins having good compatibility with wax are used, including terpene phenol resin, terpene resin,
Examples include aliphatic petroleum resins, aromatic petroleum resins, cyclopentadiene petroleum resins, chromindene resins, styrene resins, isoprene resins, rosin and rosin derivatives, polymerized rosin, rosin esters, etc. - They may be used alone or in combination.

The compatibility between wax and resin can be determined by heating and melting a mixture of the two at a temperature above the softening point to form a film, and then checking the transparency of the mixture film after cooling. A mixture of 5 parts by weight of wax and a film containing 5 parts by weight of wax with respect to the distorted area is preferable, and the transparency of the film does not decrease, that is, it does not become cloudy. At this time, the adhesion of the ink film to the recording material increases.

The above-mentioned waxes are those used as surface coating agents, such as animal-based waxes (shellac wax, etc.), vegetable-based waxes (carbana wax, etc.), mineral-based waxes (montan wax, etc.), and petroleum-based waxes (paraffin wax, Mike [1 Crystalline Wax, etc.]). natural waxes such as (Tuxus, etc.), synthetic hydrocarbons (Finscher-Tropsch wax, low-molecular polyethylene wax, etc.), fatty acid esters (polyethylene glycol, stearic acid, etc.), modified waxes (montan derivatives, etc.).

(microwax derivatives, etc.) and synthetic waxes such as amine/amide type waxes (Acrawax).

Depending on the polarity of the wax, there will be a difference in compatibility with the above resins, but paraffin wax, microcrystalline wax, Fifshire Troops wax, low molecular weight polyethylene wax, attenuated polypropylene,
For recording materials coated with low polar wax used as external wax such as alpha olefin wax, use terpene phenol resin for inks that use solvents whose main components are methyl ethyl ketone or alcohols. is preferred.

The above-mentioned terpene phenol resin is a purified polymer of α-pinene and p-pinene obtained from pine essential oil, and is a copolymer of terpene and phenol such as bisphenol. Any molar ratio of terpene to phenol can be used, but for recording materials coated with wax, the molar ratio is preferably one in which the ratio of terpene is greater than terpene:phenol = 5:5.

The content of terpene phenol resin in the ink composition is 2
~)0% by weight is preferred.

The ink composition of the present invention may include epoxy-based,
Resins that are compatible with the above-mentioned waxes and are soluble in solvents, such as phenol-based, acrylic-based, cellulose-based, and salt-vinyl acetate-based resins, can also be used in combination.

The mixing ratio of these +N fats should be limited to 2 to 1 resin having good compatibility with wax, and preferably less than this.

The organic solvent used in the present invention is preferably a solvent containing methyl ethyl ketone, methanol or ethanol from the viewpoints of solubility of the metal-containing dye, electrical conductivity of the ink composition, and drying property of the ink.

In the present invention, other organic solvents such as water, aqueous ammonia, other alcohols such as propatool, other ketones such as dimethyl ketone and diethyl ketone, glycols and glycol ethers, esters, hydrocarbons,
One or more organic solvents such as amides, amino alcohols, morpholine, nitrogen-containing compounds such as pyridine, etc. may be used as necessary to improve the solubility of the resin or metal-containing dye and the drying properties of the ink. May be used together.

The ink composition of the present invention can be produced by a normal jet printer ink production method, and
It can be used in the same way as a normal chef's printer.

Furthermore, the ink composition of the present invention can be used not only for continuous inkjet blink printing but also for drop printing.
It can also be used as an ink for other ink shared recording systems such as on-demand.

Example Next, the present invention will be explained in detail.

Note that "part 1" indicates parts by weight.

Example I C,l 5 parts of Solvent Black 29 25 parts of YS Polyster 2130 (Terpene-phenol resin manufactured by Yasuyu Kogyo ■) 10 parts of propylene glycol monomethyl ether 40 parts of methyl ethyl ketone 20 parts of methanol The above materials were thoroughly stirred and melted. Thereafter, this solution was filtered using a 1.2 micron membrane filter to obtain an ink for a Genod printer.

Example 2 c, r, Solvent Black 29 5 parts Tamanol 803 25 parts (terpene-phenol resin manufactured by Arayo Kagaku ■) Propylene glycol monomethyl ether 10 parts Methyl ethyl ketone 40 parts Ethanol 25 parts Example except that the above mixture was used An ink for a diend printer was obtained in the same manner as in 1.

Example 3 C,1, Solvent Black 4310 parts YS Polyster T I30 25 parts (Terpene-Phenol Resin made specially by Yasushi Kogyo Kogyo) Methyl ethyl ketone
45 parts methanol
A jet printer ink was obtained in the same manner as in Example 1 except that 15 parts of the above-mentioned material was used.

Example 4 C,1, Solvent Black 29 2 parts c, i
, Solvent Black 43 5 parts YS Polyster T I30 30 parts (Yasuyu Kogyo n
terpene-phenolic resin) methyl ethyl ketone
43 parts ethanol
An ink for a jet printer was obtained in the same manner as in Example 1 except that 20 parts of the above product was used.

Example 5 C,1, Solvent Black 29 7 parts VS Polyster Well 2130 20 parts Epicoat 1
004 5 parts (epoxy resin manufactured by Shell Chemical Co., Ltd.) Methyl ethyl ketone 18 parts Methanol 50 parts An ink for a jet printer was obtained in the same manner as in Example 1 except that the above-mentioned materials were used.

Example 6 C, 1, Solvent Black 27 7 parts ys Polyster 21) 0 20 parts (Terpene-phenol hot oil manufactured by Yasushi Oil Industry ■) "Epicoat"
Ink for a jet printer was obtained in the same manner as in Example 1 except that the above materials were used.

Example 7 C, 1, Solvent Black 27 7 Wys
Polyster II 21) 5 12 parts (terpene-phenol resin manufactured by Yasushi Oil Co., Ltd.) Vinylite VMCCJ 6 parts (salt-acetic acid bimaleic acid copolymer resin manufactured by Union Carbide) Methyl ethyl ketone 57 parts Methanol 18 parts Other than using the above-mentioned materials An ink for a jet printer was obtained in the same manner as in Example 1.

Using the inks of Examples 1 to 4 above, using a continuous inkjet printer, a metal plate coated with 1.0 mg/100cj of paraffin wax with a melting point of 140°F, and 1 coated with microcrystalline wax with a melting point of 160°F. .0mg/100 c1) Coated metal plate with 0.0mg/100c of Finscher Lobswax, melting point 220°F.
5 a+g/100-coated metal plate and melting point 240
°F polyethylene wax 0,5 g/100-
Printing was performed on four types of coated metal plates.

As a result, all inks had excellent jetting stability, and clear printed images were obtained on all four types of metal plates coated with wax. The adhesion of the printed image was evaluated by applying cellophane adhesive tape (Cellophane adhesive tape made by Chiban) to the resulting printed image and then peeling off the cellotape, and it was found that wax was applied to both inks.4
It had good adhesion to various types of metal plates. Furthermore, the printed image was heated to a steam temperature of 135°C using a retort pot tester.
Adhesion was evaluated after treatment for 90 minutes. As a result, there was no peeling of the printed image, and good adhesion was observed in the same cellophane tape peeling test as above.

Further, as a result of conducting an exposure test of the printed image for 50 hours using a sunshine fade meter, the printed image showed almost no fading and had good light resistance.

Using the inks of Examples 5-7 above, using a continuous inkjet printer, the melting point was 140°F.
Printing was carried out on metal plates, glass, plastic plates (acrylic resin, vinyl chloride resin, polypropylene resin, etc.) and metal plates (aluminum, stainless steel) coated with 1.01) g/100 aJ of paraffin wax.

As a result, all inks had excellent jetting stability and clear printed images were obtained. As a result of conducting the same tests as in Examples 1 to 4 on metal plates coated with paraffin wax, all inks had good adhesion and light resistance.

The adhesion of the printed images was evaluated by applying "cellotape" to the printed images on glass, plastic, and metal plates, and then peeling off the "cellotape", and it was found that the images had good adhesion.

Comparative Example An ink having the following composition as described in Example 1) of JP-A-62-109870 was prepared.

Cyclohexanone 60 parts Ethanol 33 parts Polyvinyl butyral 0.4 parts (manufactured by Denki Kagaku Kogyo ■) Mesitylene resin 2.0 parts (manufactured by Tenden Deerez ■) Cachet Resin 178B (manufactured by Cachet ■) 2.0 parts Oil Black 7HBB (manufactured by Orient Chemical Industry) 1.5i
9 Paris Far Straight Well 3304 0.6 parts (C4H9) 32.8 parts of N-NO3. Paraffin wax with a melting point of 140 °F was prepared in the same manner as in Examples 1 to 7 at 1 ° Omg/
100-Printing was performed on the coated metal plate, and adhesion was evaluated in the same manner as in Examples 1-7.

As a result, in the Sellotape peel test, the printed image peeled off and the stamped image on the metal plate coated with wax became illegible.

Effects of the Invention According to the present invention, by incorporating a sealant that has good compatibility with wax, it is possible to form a printed image that has excellent adhesion, especially to a recording material coated with wax. In addition, when a metal-containing dye is further added as an oil-soluble dye, it becomes possible to obtain a suitable electrical conductivity without using ionizable salts, so unlike inks using conventional ionizable salts, Not only does it not impair the adhesion to the recording material, it is also possible to form a printed image with even better adhesion, especially to the recording material coated with wax. Since it does not contain highly polar substances, it has excellent jetting stability and light resistance as a jet printer ink.

April 19, 1999

Claims (5)

[Claims] (1) An ink composition for jet printers containing an oil-soluble dye, a resin, and an organic solvent, wherein the resin component contains a resin that is compatible with wax. (2) The ink composition for a jet printer according to claim 1, wherein the resin having good compatibility with wax is a terpene phenol resin. (3) The ink composition for a jet printer according to claim 2, wherein the content of the terpene phenol resin is in the range of 2 to 50% by weight. (4) The oil-soluble dye is a metal-containing dye, and its content is 0.
．． The ink composition for jet printers according to any one of claims 1 to 3, characterized in that the content is in the range of 1 to 15% by weight. (5) The ink composition for a jet printer according to any one of claims 1 to 4, wherein the organic solvent contains methyl ethyl ketone, methanol, or ethanol.