JP5928802B2 - Water-based ink for ink jet recording, ink cartridge, ink jet recording apparatus, and ink jet recording method - Google Patents

Description

  The present invention relates to an aqueous ink for inkjet recording, an ink cartridge, an inkjet recording apparatus, and an inkjet recording method.

  Conventionally, as a cyan dye used in water-based ink for ink-jet recording, C.I. I. Direct Blue 199 and C.I. I. Acid Blue 9 and the like are known (Patent Document 1). Although these cyan dyes are excellent in jetting stability, there is a problem in water resistance due to a large decrease in color density before and after immersion of the recorded matter in water.

JP 2007-16225 A

  Examples of cyan dyes having excellent water resistance include C.I. I. There is Acid Blue 90. However, C.I. I. Acid Blue 90 has a problem in that it is likely to meet when dissolved in water, resulting in poor ejection.

  Accordingly, an object of the present invention is to provide a water-based ink for ink-jet recording which is excellent in water resistance and dischargeability.

In order to achieve the above object, the water-based ink for inkjet recording of the present invention comprises:
A water-based ink for inkjet recording comprising a colorant, water and a water-soluble organic solvent,
The colorant is C.I. I. Including Acid Blue 90,
The water-based ink further includes a nonionic surfactant having an HLB of 12 or more,
The amount of the nonionic surfactant based on the total amount of the water-based ink is 0.5% by weight or more.

  The water-based ink of the present invention includes C.I. I. Since Acid Blue 90 is used and the nonionic surfactant having the specific HLB is included in an amount of 0.5% by weight or more, both water resistance and dischargeability are excellent.

FIG. 1 is a schematic perspective view showing an example of the configuration of the ink jet recording apparatus of the present invention.

  The water-based ink for inkjet recording of the present invention (hereinafter sometimes referred to as “water-based ink” or “ink”) will be described. The water-based ink of the present invention contains a colorant, water, and a water-soluble organic solvent. As described above, the colorant is C.I. I. Includes Acid Blue 90. C. I. By using Acid Blue 90, a water-based ink having excellent water resistance can be obtained.

  C. with respect to the total amount of the water-based ink. I. The compounding quantity of the acid blue 90 is not specifically limited, For example, it is 0.1 weight%-20 weight%, Preferably, it is 0.3 weight%-10 weight%.

  The colorant may be C.I. I. In addition to Acid Blue 90, other dyes and pigments may also be included.

  The water is preferably ion exchange water or pure water. The blending amount (water ratio) of the water with respect to the total amount of the water-based ink is, for example, 10% by weight to 90% by weight, and preferably 40% by weight to 80% by weight. The said water ratio is good also as the remainder of another component, for example.

  Examples of the water-soluble organic solvent include a wetting agent that prevents drying of the water-based ink at the nozzle tip of the ink jet head and a penetrating agent that adjusts the drying speed on the recording medium.

  The wetting agent is not particularly limited, and examples thereof include lower alcohols such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol; dimethylformamide, dimethylacetamide Amides such as acetone; Ketones such as acetone; Keto alcohols such as diacetone alcohol; Ethers such as tetrahydrofuran and dioxane; Polyhydric alcohols such as polyalkylene glycol, alkylene glycol, glycerin and trimethylolpropane; 2-pyrrolidone; N-methyl- 2-pyrrolidone; 1,3-dimethyl-2-imidazolidinone and the like. Examples of the polyalkylene glycol include polyethylene glycol and polypropylene glycol. Examples of the alkylene glycol include ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, thiodiglycol, and hexylene glycol. These wetting agents may be used alone or in combination of two or more. Among these, polyhydric alcohols such as alkylene glycol and glycerin are preferable.

  The blending amount of the wetting agent with respect to the total amount of the water-based ink is, for example, 0% by weight to 95% by weight, preferably 5% by weight to 80% by weight, and more preferably 5% by weight to 50% by weight. is there.

  Examples of the penetrant include glycol ether. Examples of the glycol ether include ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol-n-propyl ether, diethylene glycol methyl ether, diethylene glycol ethyl ether, diethylene glycol-n-propyl ether, diethylene glycol-n-butyl ether, diethylene glycol-n- Hexyl ether, triethylene glycol methyl ether, triethylene glycol ethyl ether, triethylene glycol-n-propyl ether, triethylene glycol-n-butyl ether, propylene glycol methyl ether, propylene glycol ethyl ether, propylene glycol-n-propyl ether, Propylene glycol-n-butyl ether , Dipropylene glycol methyl ether, dipropylene glycol ethyl ether, dipropylene glycol-n-propyl ether, dipropylene glycol-n-butyl ether, tripropylene glycol methyl ether, tripropylene glycol ethyl ether, tripropylene glycol-n-propyl ether And tripropylene glycol-n-butyl ether. The said penetrant may be used individually by 1 type, and may use 2 or more types together.

  The blending amount of the penetrant with respect to the total amount of the water-based ink is, for example, 0% by weight to 20% by weight, preferably 0.1% by weight to 15% by weight, and more preferably 0.5% by weight to 10% by weight.

  As described above, the water-based ink further includes a nonionic surfactant having an HLB value of 12 or more, which is a value representing the degree of affinity of the surfactant. Nonionic surfactants having an HLB of 12 or more include, for example, Olphine (registered trademark) E1010 (HLB = 13.5) and E1020 (HLB = 15.5), Kao Corporation, manufactured by Nissin Chemical Industry Co., Ltd. ) Emulgen (registered trademark) 108 (HLB = 12.1), 409PV (HLB = 12.0), 707 (HLB = 12.1), 709 (HLB = 13.3), 123P (HLB = 16.1). 9), 420 (HLB = 13.6), 109P (HLB = 13.6), 120 (HLB = 15.3), 130K (HLB = 18.1), 147 (HLB = 16.3), 150 ( HLB = 18.4), 220 (HLB = 14.2), 320P (HLB = 13.9), 350 (HLB = 17.8) and 430 (HLB = 16.2), Rheodor® TW− L 06 (HLB = 13.3), TW-O120V (HLB = 15.0), TW-L120 (HLB = 16.7), TW-P120 (HLB = 15.6), TW-S120 (HLB = 14.1). 9) and Super TW-L120 (HLB = 16.0). The said nonionic surfactant may be used individually by 1 type, and may use 2 or more types together.

  The blend amount of the nonionic surfactant with respect to the total amount of the water-based ink is 0.5% by weight or more. By setting the blend amount of the nonionic surfactant to 0.5% by weight or more, it is possible to obtain a water-based ink excellent in dischargeability. If the amount of the nonionic surfactant is too large, Acid Blue 90, which is a colorant, is likely to dissolve in water, resulting in poor water resistance. On the other hand, if the amount is too small, the effect of suppressing the association between the acid blues 90 becomes poor, and the discharge performance deteriorates. The blend amount of the nonionic surfactant is preferably 0.5% by weight to 3% by weight, and more preferably 0.5% by weight to 2% by weight.

  The upper limit of the HLB of the nonionic surfactant is preferably 16.9 or less. By setting the HLB of the nonionic surfactant to 16.9 or less, a water-based ink that is superior in water resistance can be obtained. The HLB of the nonionic surfactant is more preferably 12 to 13.5. The higher the value of HLB, the higher the hydrophilicity, and the lower the value, the higher the lipophilicity. That is, if HLB is too high, acid blue 90, which is a colorant, is likely to dissolve in water, resulting in poor water resistance. On the other hand, if the HLB value is too low, the nonionic surfactant does not dissolve in the water-based ink, so that nozzle clogging is likely to occur and ejection stability is not good.

  The water-based ink may further contain a conventionally known additive as required. Examples of the additive include a pH adjusting agent, a viscosity adjusting agent, a surface tension adjusting agent, and an antifungal agent. Examples of the viscosity modifier include polyvinyl alcohol, cellulose, and a water-soluble resin.

  The water-based ink is prepared by, for example, uniformly mixing a colorant, water, a water-soluble organic solvent and the nonionic surfactant with other additive components as necessary, using a conventionally known method, and using a filter or the like. It can be prepared by removing the lysate.

  Next, the ink cartridge of the present invention will be described. The ink cartridge of the present invention is an ink cartridge containing a water-based ink for ink-jet recording, and the water-based ink is the water-based ink for ink-jet recording of the present invention. As the main body of the ink cartridge, for example, a conventionally known one can be used.

  Next, the ink jet recording apparatus and the ink jet recording method of the present invention will be described.

  The ink jet recording apparatus of the present invention is an ink jet recording apparatus that includes an ink storage portion and an ink discharge means, and discharges ink stored in the ink storage portion by the ink discharge means. The water-based ink for inkjet recording is accommodated.

  The ink jet recording method of the present invention is an ink jet recording method for recording by ejecting a water-based ink onto a recording medium by an ink jet method, wherein the water-based ink for ink-jet recording of the present invention is used as the water-based ink.

  The ink jet recording method of the present invention can be performed using, for example, the ink jet recording apparatus of the present invention. The recording includes printing, printing, printing, and the like.

  FIG. 1 shows the configuration of an example of the ink jet recording apparatus of the present invention. As shown in the figure, this ink jet recording apparatus 1 includes four ink cartridges 2, an ink discharge means (ink jet head) 3, a head unit 4, a carriage 5, a drive unit 6, a platen roller 7, and a purge device 8. And as a major component.

  The four ink cartridges 2 contain one color each of four colors of water-based inks of yellow, magenta, cyan, and black. For example, the water-based cyan ink is the water-based ink for inkjet recording of the present invention. Other water-based inks may be general water-based inks. The ink jet head 3 installed in the head unit 4 performs recording on a recording medium (for example, recording paper) P. Four ink cartridges 2 and a head unit 4 are mounted on the carriage 5. The drive unit 6 reciprocates the carriage 5 in the linear direction. As the drive unit 6, for example, a conventionally known one can be used (for example, see Japanese Patent Application Laid-Open No. 2008-246821). The platen roller 7 extends in the reciprocating direction of the carriage 5 and is disposed to face the inkjet head 3.

  The purge device 8 sucks out defective ink containing bubbles and the like accumulated in the ink jet head 3. As the purge device 8, for example, a conventionally known device can be used (see, for example, JP-A-2008-246821).

  A wiper member 20 is disposed adjacent to the purge device 8 on the platen roller 7 side of the purge device 8. The wiper member 20 is formed in a spatula shape, and wipes the nozzle formation surface of the inkjet head 3 as the carriage 5 moves. In FIG. 1, a cap 18 covers a plurality of nozzles of the inkjet head 3 that is returned to the reset position when recording is completed in order to prevent the water-based ink from drying.

  In the ink jet recording apparatus 1 of this example, four ink cartridges 2 are mounted on one carriage 5 together with the head unit 4. However, the present invention is not limited to this. In the ink jet recording apparatus, each of the four ink cartridges 2 may be mounted on a carriage different from the head unit 4. Further, each of the four ink cartridges 2 may not be mounted on the carriage 5 but may be arranged and fixed in the ink jet recording apparatus. In these aspects, for example, each cartridge of the four ink cartridges 2 and the head unit 4 mounted on the carriage 5 are connected by a tube or the like, and each cartridge of the four ink cartridges 2 is connected to the head unit 4 from the cartridge. Aqueous ink is supplied.

  Ink jet recording using this ink jet recording apparatus 1 is performed as follows, for example. First, the recording paper P is fed from a paper feed cassette (not shown) provided on the side of or below the ink jet recording apparatus 1. The recording paper P is introduced between the inkjet head 3 and the platen roller 7. Predetermined recording is performed on the introduced recording paper P by water-based ink ejected from the inkjet head 3. The water-based ink of the present invention can be stably ejected from the inkjet head 3. The recording sheet P after recording is discharged from the inkjet recording apparatus 1. By using the water-based ink of the present invention, a recorded matter having excellent water resistance can be obtained. In FIG. 1, the paper feed mechanism and paper discharge mechanism for the recording paper P are not shown.

  The apparatus shown in FIG. 1 employs a serial type ink jet head, but the present invention is not limited to this. The ink jet recording apparatus may be an apparatus that employs a line type ink jet head.

  Next, examples of the present invention will be described together with comparative examples. In addition, this invention is not limited and restrict | limited by the following Example and comparative example.

[Example 1-14 and Comparative Example 1-12]
Each component of the water-based ink composition (Tables 1 and 2) was mixed uniformly. Thereafter, the obtained mixture was filtered using a hydrophilic polytetrafluoroethylene (PTFE) type membrane filter (pore size 0.20 μm) manufactured by Toyo Roshi Kaisha, Ltd., so that Examples 1 to 14 and Comparative Example 1 were used. -12 water-based inks for inkjet recording were obtained.

  About the water-based ink of an Example and a comparative example, (a) discharge property evaluation and (b) water resistance evaluation were implemented by the following method.

(A) Evaluation of ejectability Purging after replacement of an ink cartridge using the water-based inks of Examples and Comparative Examples using a digital composite machine DCP-385C equipped with an ink jet printer manufactured by Brother Industries, Ltd. Immediately after performing the suction of water-based ink by the pump of the main body DCP-385C) three times, a recording test was performed to determine the ratio of the discharge nozzle to the total number of nozzles, and the evaluation was performed according to the following evaluation criteria.

Evaluation criteria G: Discharge nozzle ratio relative to the total number of nozzles was 90% or more NG: Discharge nozzle ratio relative to the total number of nozzles was less than 90%

(B) Water resistance evaluation Cyan with a resolution of 600 dpi × 600 dpi on plain paper (My Paper manufactured by Ricoh) using the water-based inks of Examples and Comparative Examples using the digital multifunction device DCP-385C equipped with an inkjet printer. An image including a single color patch was recorded to produce an evaluation sample. After the evaluation sample was immersed in pure water for 5 minutes, the bleeding of the image was visually evaluated according to the following evaluation criteria.

Evaluation of water resistance Evaluation criteria AA: No bleeding A: Slight bleeding occurred B: Although there was some bleeding, the level was practically no problem C: There was a level of bleeding causing practical problems

  Table 1 shows the water-based ink composition and evaluation results of the water-based inks of the examples. Table 2 shows the water-based ink composition and evaluation results of the water-based ink of the comparative example.

  As shown in Table 1, Examples 1 to 14 were excellent in both dischargeability and water resistance. Examples 1 and 2 in which the blending amount of the nonionic surfactant having an HLB of 13.5 is 0.50 wt% to 2.00 wt%, and the nonionic surfactant having an HLB of 12.1 or 12.0 In Examples 4 to 6 in which the blending amount was 3.00% by weight, the results of water resistance evaluation were extremely excellent. In Examples 3, 7 and 8 in which the blending amount of the nonionic surfactant having an HLB of 13.5 or 13.3 was 3.00% by weight, the results of water resistance evaluation were particularly excellent.

  On the other hand, as shown in Table 2, C.I. I. Instead of Acid Blue 90, C.I. I. Direct Blue 199 or C.I. I. In Comparative Examples 1 and 2 using Acid Blue 9, the results of water resistance evaluation were poor. Moreover, in the comparative example 3 which did not use a nonionic surfactant, the result of discharge property evaluation was bad. And also in Comparative Examples 4 to 6 in which the blending amount of the nonionic surfactant of HLB was less than 0.5% by weight, the result of the dischargeability evaluation was bad. Furthermore, in Comparative Examples 7 to 12 using a nonionic surfactant having an HLB of less than 12, the results of the evaluation of dischargeability were poor.

  As described above, the water-based ink of the present invention is excellent in both water resistance and dischargeability. The use of the water-based ink of the present invention is not particularly limited, and can be widely applied to various ink jet recordings.

DESCRIPTION OF SYMBOLS 1 Inkjet recording apparatus 2 Ink cartridge 3 Ink discharge means (inkjet head)
4 Head unit 5 Carriage 6 Drive unit 7 Platen roller 8 Purge device

Claims (4)

A water-based ink for inkjet recording comprising a colorant, water and a water-soluble organic solvent,
The colorant is C.I. I. Including Acid Blue 90,
The water-based ink further includes a nonionic surfactant having an HLB of 12 to 12.1 .
A water-based ink for ink-jet recording, wherein the nonionic surfactant is added in an amount of 0.5% by weight or more based on the total amount of the water-based ink. An ink cartridge comprising an ink-jet recording water-based ink, ink cartridge, wherein the aqueous ink is an aqueous inkjet recording ink according to claim 1 Symbol placement. An ink jet recording apparatus that includes an ink container and an ink discharge unit, and discharges the ink stored in the ink container by the ink discharge unit,
It said ink containing portion, an ink jet recording apparatus characterized by an ink-jet recording water-based ink according to claim 1 Symbol placement is accommodated. An ink jet recording method for recording by ejecting aqueous ink on a recording medium by an ink jet method,
Wherein as an aqueous ink, an ink jet recording method which comprises using the water-based ink for ink jet recording of claim 1 Symbol placement.

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