JP3179562B2 - Ink container and ink distribution member - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention is an ink circulation member for circulation of the ink in the container and in the printer for storing oily ink used in an inkjet printer, Narabiniko
The present invention relates to a method for forming an image by using them .

[0002]

2. Description of the Related Art Conventionally, a general ink-jet printer has a structure in which ink droplets ejected from a nozzle having an inner diameter of 10 to 400 .mu.m collide with a sheet provided in the ejecting direction, and then the solvent in the ink is dried to form a sheet. This is a non-impact recording method in which recording is performed by fixing a dye of ink on the top. For this reason, an extremely high-definition image can be obtained with low noise, and further, there is an advantage that colorization can be easily performed. This ink generally includes an aqueous ink using water as a main solvent and an oil-based ink using an organic solvent as a main solvent.

[0003] Printed images using water-based inks are generally
Oil-based inks can provide a printed image with excellent water resistance, and have poor water resistance and are difficult to print on a substrate having a hydrophobic surface. There is an advantage that recording to a personal computer is easy.

[0004] Although oil-based inks have the above-mentioned advantages, similar to water-based inks, ink ejection abnormalities occur due to factors such as clogging of nozzles, clogging of filters, and changes in physical properties of ink over time. It is easy to spread the method. To solve these shortcomings,
Various improvements have been proposed for ink compositions, such as colorants, solvents, additives, and the like.

[0005]

However, when oil-based ink stored in a container for a certain period of time is used, there is a problem that stable ejection cannot be obtained. In particular, in the so-called electric field control system using electrostatic force, there is a drawback that jetting becomes extremely unstable when oil-based ink, particularly oil-based ink having a specific resistance of 1 × 10 ⁶ Ω · cm or more is used.

[0006] An object of the present invention is to provide an ink container and an ink distribution member for obtaining an extremely excellent storage stability of an oil-based ink in an ink jet recording system using an oil-based ink. is there.

[0007]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have completed the present invention. That is, the present invention relates to an ink container for stably storing oil-based ink and an ink circulation member through which the oil-based ink flows in a printer.

[0008] The ink container according to claim 1 has a specific resistance of 1
× 10 ⁶ Ω · cm or more, electric field control type inkjet printer
A container for storing oil-based ink for linters.
And the container has a container body and a cap for closing the container body.
Rannahli, the material of the container body portion in contact with the oil-based ink is characterized in that a glass alkali elution amount is less than 0.1 mg.

[0009]

[0010] The ink container according to the second aspect is the first aspect.
The material of the glass having an alkali elution amount of 0.1 mg or less in the mounted ink container is one or more selected from quartz glass, high silicate glass, and borosilicate glass. .

[0011] The ink container according to claim 3 is the same as in claim 1.
Or the ink container according to item 2, wherein the material of the cap in contact with the oil-based ink is a polymer material having a water absorption of 0.1% or less.

According to a fourth aspect of the present invention, the ink distribution member has a specific resistance.
Is an electric field control type ink jet of 1 × 10 ⁶ Ω · cm or more.
Ink distribution section through which oil-based ink for printers flows
The material in contact with the oil-based ink is a glass having an alkali elution amount of 0.1 mg or less. An electric field control type ink jet according to claim 5.
The printer is provided with the ink distribution member according to claim 4.
It is characterized by becoming. The image forming method according to claim 6.
The method uses an electric field control type ink jet printer.
A method for forming an image, comprising a container for containing ink.
Container and / or an ink distribution member through which the ink flows,
As the material of the part in contact with the ink, the amount of alkali elution is
0.1 mg or less of glass is used and the specific resistance is 1 × 10
It is characterized by using oil-based ink of ⁶ Ω · cm or more.
You.

Hereinafter, the present invention will be described in detail. Generally, soda-lime glass is used as a glass material used for the container body. This soda-lime glass is widely used because its raw material is inexpensive, easy to mold, and has excellent chemical durability, but the alkali component is eluted due to the slight reaction between water and aqueous solution and glass. It is known.

The oil-based ink does not substantially contain water, but when stored in a container made of soda-lime glass for a long period of time, the characteristics of the ink may be changed, and the corrosion of the electrode and the ejection stability may be deteriorated. After examination, it became clear. From this fact, it is conceivable that the alkaline component is eluted from the soda-lime glass even in the oil-based ink containing substantially no water.

[0015] Oil-based ink, in particular, having a specific resistance of 1 × 10 ⁶ Ω ·
cm or more of oil-based ink, the effect of glass having a large amount of alkali elution, such as soda-lime glass, is great, whereas the material of the container body in contact with the oil-based ink is glass having a alkali elution amount of 0.1 mg or less. It has been found that when stored in an ink container, long-term stable storage is possible under various environments.

The alkali elution amount of the material of the container body at the portion in contact with the oil-based ink is measured by a method specified in JIS R3502. Here, the alkali elution amount of 0.1 mg or less corresponds to the quality of the glassware for chemical analysis of the second or higher hardness.

Among glass materials having an alkali elution amount of 0.1 mg or less, quartz glass, high silicate glass, and borosilicate glass exhibit particularly excellent stability. As the quartz glass, natural quartz, artificial quartz, quartzite, quartz sand, Si
It is possible to use those obtained by melting a raw material such as Cl by various methods. As the high silicate glass, specifically, Vycor glass 7900/7905 (manufactured by Corning Glass) can be used. As the borosilicate glass, specifically, Pyrex glass 7740
(Corning Glass Works), Iwaki Code 774
No. 0 glass (manufactured by Iwaki Glass), Hario 32 (manufactured by Shibata Scientific Instruments), Beadrex (manufactured by Kokura Glass), and various other commercially available borosilicate glasses (hard glass) can be used.

When the oil-based ink is stored for a long period of time with the container body open, the stability of the ink is impaired due to foreign matter such as moisture, dirt and dust mixed in from the outside. Therefore, it is necessary to seal the container body. The glass may be fused to form an ampule, but it is preferable to close the container body with a cap made of plastic or the like in consideration of taking out the oil-based ink. The material of the cap in contact with the oil-based ink is preferably a polymer material having a water absorption of 0.1% or less.

When a polymer material having a water absorption of 0.1% or less is used as a cap material in a portion in contact with the oil-based ink, not only is the elution of the specific resistance lowering substance from the polymer material itself small, but also the environment is reduced. Since the moisture permeability from the atmosphere and the accompanying elution of the ionic substance from the polymer material are small, the decrease in the specific resistance after storage relative to the specific resistance value of the initial oil-based ink is small, and it is within the allowable range of the ejection of the printer. This is because the dissolution stability of the ink is not impaired.

Conversely, when a polymer material having a water absorption of more than 0.1% is used as a cap material in a portion in contact with the oil-based ink, even if the elution of the substance causing a decrease in specific resistance from the polymer material itself is low, the environment is not affected. Great permeability from the atmosphere,
In addition, the leaching of ionic substances from the polymer material accompanying this causes a large drop in the specific resistance of the oil-based ink after storage relative to the specific resistance of the initial oil-based ink. Is also thought to decrease.

Specific examples of the polymer material in the portion in contact with the oil-based ink of the cap include preferably polyolefins such as polyethylene, polypropylene, polytetrafluoroethylene, and polyvinylidene chloride, but are not limited thereto. Absent. The material of the portion of the cap that does not come into contact with the oil-based ink can be arbitrarily selected. The water absorption here is the water absorption of the polymer material after being left for 24 hours at an ambient temperature of 23 ° C. defined by the method of ASTM D570.

Next, the composition of the oil-based ink contained in the ink container of the present invention will be described. As the colorant to be contained in the oil-based ink composition, any oil-based dye that can be dissolved or dispersed in an organic solvent, or any organic or inorganic pigment can be used. Is preferred. For example, typical types include azo dyes, metal complex dyes, naphthol dyes, anthraquinone dyes, indigo dyes, carbonium dyes, quinoimine dyes, cyanine dyes, quinoline dyes, nitro dyes, nitroso dyes, benzoquinone dyes, naphthoquinone dyes, and naphthalimide. Dyes, perinone dyes, phthalocyanine dyes and the like are not limited to these. These colorants can be used alone or in combination of two or more.

The concentration of the colorant is in the range of 0.1 to 20% by weight in 100% by weight of the oil-based ink composition in order to obtain an excellent printed image while maintaining the ejection stability and storage stability of the ink. Is preferable, and the range of 1 to 10% by weight is more preferable in terms of printing density and ink stability.

The organic solvent contained in the oil-based ink composition varies depending on the type of the coloring agent. However, even when a solvent-soluble oil-soluble dye is used, it is not essential to use a dye. It is not necessary to use only a good solvent having excellent compatibility, and a mixture of two or more good solvents or a mixture of a good solvent and a general solvent may be used. Further, it may be used in combination with a dye dissolving agent.

Examples of the organic solvent used herein include linear hydrocarbons, branched hydrocarbons, naphthenic hydrocarbons, mono- or di-substituted linear or branched alkylnaphthalenes, phenyl, biphenyl, Or a linear or branched alkyl derivative of terphenyl, phenyl,
Linear or branched alkylene derivatives of biphenyl or terphenyl, xylylethane, aromatic hydrocarbons such as pheneticlecumene, aliphatic alcohols such as ethanol, ketones such as methyl ethyl ketone, glycols such as ethylene glycol, glycols mono,
Di-substituted linear or branched alkyl ethers, mono- or di-substituted linear or branched alkylene ethers of glycols, esters of glycols, fatty acids and fatty acid esters, nitrogen-containing compounds such as amide-pyrrolidone compounds,
Examples include hydroxybenzoic acid esters such as 2-ethylhexyl p-hydroxybenzoate, but are not limited to these organic solvents.

However, among the above organic solvents, highly polar compounds such as alcohols, ketones, pyrrolidones, esters, glycols, and amides greatly affect the specific resistance of the oil-based ink. 1 × 10 ⁶ Ω
-If it is more than cm, it is necessary to pay attention to the addition amount.

The content of the organic solvent in the oil-based ink composition can be made up of all components except for the colorant when no other additives are used. It is preferable that the total amount of the solvent components used as the good solvent is 0.1% by weight or more.

If necessary, the oil-based ink composition may contain a UV absorber, another light stabilizer, a stabilizer such as an antioxidant, a surfactant such as a dispersant, a binder resin, and the like. it can. Examples of the antioxidant include B
Compounds such as HA (2,3-di-tert-butyl-4-oxyanisole) and BHT (2,6-di-tert-butyl-p-cresol) are exemplified. Anionic and cationic surfactants are used. Any of amphoteric, non-ionic and non-ionic types can be used. Specific examples of the resin that can be used as the binder resin include an acrylic resin, a styrene acrylic resin, a rosin-modified resin, a phenol resin, a terpene-based resin, a polyester resin, a polyamide resin, and an epoxy resin. When a compound such as wax which is solid at room temperature is used as a hot melt ink, it functions as a solvent at the time of melting and can be applied as a solvent in the oil-based ink composition contained in the ink container of the present invention.

[0029]

The present invention will be specifically described below with reference to examples. (Production Example) Phthalocyanine dye 5% by weight 2-ethylhexyl p-hydroxybenzoate 10% by weight Phenethyl cumene 85% by weight After mixing the above components and sufficiently dissolving at room temperature,
Filtration was performed using a 0.5 micron membrane filter to obtain an oil-based ink. At this time, the specific resistance of the oil-based ink was 3.5 × 10 ⁷ Ω · cm.

(Example) The oil-based ink of the production example was made of Iwaki Code 7740 glass (having an alkali elution amount of 0.025 m
g) and an ink container consisting of a cap made of polypropylene (having a water absorption of 0.02% or less after 24 hours at 23 ° C.), sealed and sealed in an environment at a temperature of 60 ° C. and a humidity of 60%. As a result of storage for a year, the specific resistance of the oil-based ink is 3.
2 × 10 ⁷ Ω · cm, no precipitate was generated, and stable ejection was obtained using an electrostatic suction type jet printer (beam jet). Furthermore, the alkali elution amount is 0.1
mg or less of glass was used as a material for not only the ink container but also for pipes, pipe joints, and all other parts of the oil-based ink in the jet printer. As a result, stable ejection was obtained.

(Comparative Example) In place of the Iwaki cord 7740 glass of the embodiment, a container body made of normal glass (soda silicate glass and alkali elution amount: 2.0 mg) and polypropylene (water absorption rate after 24 hours at 23.degree. As a result of performing the same test as in the example using an ink container having a cap of not more than 02%), a minute amount of precipitate was generated, and the specific resistance of the oil-based ink was reduced to 8.5 × 10 ⁶ Ω · cm. , Showed abnormal injection.

[0032]

According to the present invention , an electrode having a specific resistance of 1 × 10 ⁶ Ω · cm or more,
According to the ink container of the present invention in which a container for containing oil-based ink for a field-control type ink jet printer, the material of the container body in a portion in contact with the oil-based ink is glass whose alkali elution amount is 0.1 mg or less, There is an advantage that the specific resistance and dissolution stability during storage of the ink are remarkably excellent. An ink container in which the glass material having an alkali elution amount of 0.1 mg or less is one or two or more selected from quartz glass, high silicate glass, and borosilicate glass has an advantage that the above effect is particularly excellent. . The material of the cap in contact with the oil-based ink has a water absorption of 0.1%
According to the ink container of the present invention, which is the following polymer material,
There is an advantage that the oil-based ink can be easily taken out and the specific resistance and the dissolution stability during storage of the oil-based ink are excellent. Therefore, when the ink container and the ink distribution member of the present invention are used for an ink jet printer or the like, stable ink ejection can be obtained.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masayoshi Miura 3-10-1 Higashi-Mita, Tama-ku, Kawasaki City, Kanagawa Prefecture Inside Matsushita Giken Co., Ltd. (72) Inventor Shuko Kanematsu 3-, Higashi-Mita Tama-ku, Kawasaki City, Kanagawa Prefecture 10-1 Matsushita Giken Co., Ltd. (72) Inventor Katsuhiko Bando 247 Fukutake Ko, Saijo City, Ehime Prefecture Matsushita Kotobuki Electronics Co., Ltd. In-company (56) References JP-A-4-37632 (JP, A) JP-A-2-192436 (JP, A) JP-A-60-260443 (JP, A) JP-A-2-175630 (JP, A) JP-A-4-290752 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41J 2/175 B43L 25/00

Claims (6)

(57) [Claims] An electric cell having a specific resistance of 1 × 10 ⁶ Ω · cm or more.
Oil-based inks for field-controlled inkjet printers
A container for containing, the container being a container body
Les consists of a cap for closing the material of the container body of the portion in contact with the oil-based ink, an alkali elution amount is 0.1mg
An ink container comprising the following glass. 2. The method according to claim 1, wherein the alkali elution amount is 0.1 mg or less.
Glass material is quartz glass, high silicate glass, borosilicate
One or more selected from acid glasses
The ink container according to claim 1, wherein: 3. A cap material in a portion in contact with the oil-based ink.
The material is a polymer material with a water absorption of 0.1% or less.
The ink container according to claim 1 or 2, wherein 4. The specific resistance is 1 × 10 ⁶ Ωcm or more
Oil-based ink for field-controlled inkjet printers
An ink circulating member that circulates and is in contact with oil-based ink
If the material of the part is glass with an alkali elution amount of 0.1 mg or less
And an ink distribution member. 5. An ink circulation member according to claim 4,
Field controlled ink jet printer
- 6. Use of an electric field control type ink jet printer.
A method for forming an image, and
Container and / or ink distribution section through which ink flows
Alkali elution as the material of the material that comes into contact with the ink
Use glass with an amount of 0.1 mg or less and have a specific resistance of 1 ×
10 ⁶ It is characterized by using oil-based ink of Ω · cm or more.
Image forming method.