JPH11222568A - Ink set, ink jet recording method using the same, ink jet recording apparatus and equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly reliable ink set which can obtain an image with good water resistance and print quality even on plain paper, and which is excellent in print quality when performing continuous printing. Of an ink-jet recording method, an ink-jet recording apparatus, and equipment. SOLUTION: In an ink set including a combination of a plurality of inks used for forming an image by ejecting ink to a recording material and attaching a plurality of inks,
The ink set has at least two kinds of inks having different polarities, and a solvent for re-dissolving a reactant generated by the two kinds of inks having different polarities is one or both of the two kinds of inks. And an ink jet recording method, an ink jet recording apparatus, and equipment using the ink set.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an ink set, an ink jet recording method using the same, an ink jet recording apparatus, and equipment.

[0002]

2. Description of the Related Art In an ink-jet recording method, recording is performed by causing ink droplets to fly and causing ink to adhere to a recording material such as paper. In particular, JP-B-61-599.
No. 11, JP-B-61-59912, and JP-B-61-59914, by using an electrothermal converter as a discharge energy supply means and applying thermal energy to ink to generate bubbles. According to the ink jet recording method of a method of discharging droplets, it is possible to easily realize a high density multi-orifice of a recording head, and to record a high-resolution and high-quality image at a high speed.

However, the ink used in the conventional ink jet recording method mainly comprises a colorant and water, and further contains a water-soluble high-boiling solvent such as glycol for the purpose of preventing drying and clogging of nozzles. When recording on plain paper using such an ink, it is not possible to obtain sufficient fixing properties, or due to uneven distribution of fillers and sizing agents on the recording paper surface. However, there is a problem that a non-uniform image estimated to be generated occurs.
In particular, when a color image is to be obtained, a plurality of colors of ink are superposed one after another before a certain color ink is fixed on the recording paper. There is a problem that a satisfactory image cannot be obtained due to bleeding or uneven mixing (hereinafter referred to as bleeding).

On the other hand, Japanese Patent Application Laid-Open No. 55-65269 discloses a method for improving the fixability by adding a compound such as a surfactant to the ink to increase the permeability. Japanese Patent Application Laid-Open No. 55-66976 discloses the use of an ink mainly containing a volatile solvent. However, in the former method in which a surfactant is added to the ink, the permeability of the ink to the recording paper is increased, and although the fixing property and the bleeding of the ink are improved to some extent, the coloring material in the ink is also used. Since the ink penetrates deep into the recording paper, problems such as a reduction in image density and saturation are caused. In addition, the ink also spreads in the horizontal direction, and as a result, problems such as a decrease in edge sharpness and a decrease in resolution also occur. On the other hand, in the latter method using an ink mainly composed of a volatile solvent, in addition to the same disadvantages as in the former case described above, clogging due to evaporation of the solvent in the nozzle portion of the recording head occurs. Easy to do and not preferred.

Further, in order to improve the above-mentioned problem, many methods have been proposed in which a liquid for improving an image is preliminarily deposited on a recording material prior to ejection of ink. For example, JP-A-63-2999971 discloses that
A method is disclosed in which a liquid composition containing an organic compound having two or more cationic groups per molecule is deposited on a recording material, and recording is performed with an ink containing an anionic dye. Also, JP-A-64-9279 discloses that
There is disclosed a method in which an acidic liquid containing succinic acid is adhered onto a recording material and then recording is performed with an ink containing an anionic dye. Further, Japanese Patent Application Laid-Open No. 64-63185 discloses a method in which a liquid for insolubilizing a dye is applied prior to recording of ink.

However, substances having different polarities (the difference in polarity described here indicates a difference in anionic and cationic polarities. When these substances having different polarities are mixed, each anionic site and When a liquid composition or an ink containing a compound (which reacts with a cationic portion to form an insoluble aggregate in water) is used, the following specific problems may occur. In particular, such a problem is likely to occur when heads for ejecting inks containing substances having different polarities are close to each other.

[0007] For example, when ink is rebounded on the paper surface at the time of printing at a high ejection speed on paper with a low ink penetration speed, the liquid composition containing a cationic substance becomes anionic. There is a possibility that the ink may fly in the direction of the head for ejecting the ink containing the base. In such a case, the face of the head that has received the rebound of the liquid droplet tends to be easily stained. In addition to the above-described effects of the rebound, the ink ejected from the head flies in the air in a spray form, and adheres to the face of the head for ejecting ink having a polarity different from that of the ink. Then, similar to the case of the droplet bounce described above,
The face of the head is easily stained. Such a phenomenon is particularly remarkable when an image having a high print duty is to be printed. Therefore, when such an image is continuously printed, it is necessary to devise the wiping of the face surface, such as by increasing the number of wiping operations, and thus problems such as a decrease in throughput and an increase in cost are caused.

[0008]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an ink jet printer which can obtain an image having good water resistance and good print quality even on so-called plain paper and which has excellent print quality when performing continuous printing. An object of the present invention is to provide an ink set having excellent reliability for recording, and an ink jet recording method, an ink jet recording apparatus and equipment using the ink set.

[0009]

The above object is achieved by the present invention described below. That is, the present invention relates to an ink set including a combination of a plurality of inks used for forming an image by ejecting ink to a recording material and attaching a plurality of inks, wherein at least two inks having different polarities are included in the ink set. A solvent for re-dissolving the reactants generated by the two types of inks having different types of inks and having one of the two types of inks is contained in either one or both of the two types of inks And an ink jet recording method, an ink jet recording apparatus, and equipment using the ink set.

[0010]

Next, the present invention will be described in detail with reference to preferred embodiments of the present invention. We have:
As a result of intensive studies to solve the above-mentioned conventional technology, a specific characteristic that occurs when an ink set including at least two types of inks having different polarities is used for the purpose of improving the water resistance and print quality of an image. In order to solve the problem and stably form images excellent in water resistance and print quality without causing dirt on the face surface of the head, even in continuous printing, as well as in normal cases. In the ink set, a solvent capable of re-dissolving a reactant generated by two kinds of inks having different polarities used for image formation is included in one or both of the two kinds of inks having different polarities constituting an ink set. The inventor of the present invention has found that what is necessary is to do so.

First, when two types of inks having different polarities, A and B, are used, the extremely rarely adhered matter caused by the reaction between the two types of inks A and B causes stains on the face surface of the head. By containing a solvent that redissolves the fixed substance in one or both of the inks A, B, and B, the fixed substance can be easily re-dissolved. Generation of dirt can be prevented.

When two kinds of inks A and B having different polarities come into contact with each other on the face of the head or on the paper,
Each polar part (cationic part and anionic part)
In some cases, agglomeration may occur due to the reaction, and this agglomeration may cause non-ejection or misalignment of printing, and the agglomeration may be clogged at the nozzle tip due to wiping operation or capping. May worsen. However, also in this case, the above problem can be solved by including a solvent that redissolves the aggregate in one of the inks A and B or both inks. That is, the above-mentioned aggregate is difficult to be redissolved in a state where the concentration of the solvent is low. However, depending on the solvent contained in the ink, the binding part between the anionic site and the cationic site is separated particularly in the state where the solvent concentration is high. It was found that aggregates formed by the reaction at the respective polar portions (cationic sites and anionic sites) could be redissolved. Therefore, the aggregates formed on the face of the head, when the water in the aggregates evaporates over time, the solvent concentration in that portion increases, so the aggregates are redissolved,
As a result, the face surface of the head is always kept clean by wiping. Therefore, if a solvent that re-dissolves the aggregates is used in an ink set such that the ink is contained in either one of the inks A and B, or both the inks A and B, A and B having different polarities are used. B2
There is no danger of sticking matter generated by using different types of ink and clogging of the nozzles to cause printing deflection or non-ejection of ink, thereby improving landing accuracy. As a result, it is possible to stably form images excellent in water resistance and print quality even in continuous printing as well as in normal cases.

[0013] On the other hand, on the paper surface as a recording material, by using the ink set having the above-described structure, the interaction between inks having different polarities provides high density and good print quality, and color image formation. Good
Printing with a wide color reproduction range and good bleeding can be obtained.
Further, in such printed matter, after printing, since the solvent contained in the ink evaporates over time, only the dye remains in the cellulose of the paper, without causing any problem on the image In addition, it is possible to provide an ink set which is stable and can form good images and has excellent reliability.

The ink set of the present invention comprises a combination of a plurality of inks used to form an image by ejecting ink onto a recording material and attaching a plurality of inks, and at least two types of inks having different polarities. And a solvent for re-dissolving a reactant generated by the two kinds of inks having different polarities is contained in either one or both of the two kinds of inks. I do. The solvent used in the ink set of the present invention for re-dissolving the reactant generated by two kinds of inks having different polarities will be specifically described. The solvent that can be used in the present invention is preferably a water-soluble organic solvent, and is not particularly limited, but particularly preferred solvents include the following. Specifically, for example, 2
Pyrrolidone, N-methyl-2-pyrrolidone, formamide, formaldehyde and the like can be used. In the present invention, the content of the above-mentioned solvent in the ink is not particularly limited, but is preferably in the range of 5 to 60% by weight, more preferably 5 to 40% by weight based on the total amount of the ink liquid. is there. Actually, when the desired amount of solvent for re-dissolving the aggregate formed by the reaction of the inks having different polarities is expressed by the solvent content contained in the aggregate, it is preferably 30% to 100%. %. The greater the content, the greater the effect of re-dissolving the aggregates.

As the inks having different polarities constituting the ink set of the present invention, similarly to ordinary aqueous inks, water or an aqueous medium composed of water and a water-soluble organic solvent is used as a main component, and an anionic substance or an aqueous medium is used. It comprises one of the cationic substances and other additives and the like that are added as needed. As the anionic substance or the cationic substance used at this time, an anionic compound or a cationic compound as described below, or a water-soluble dye containing an anionic group or a cationic group described below can be used.

Examples of the cationic compound used in the present invention include polyallylamine, polyamine sulfone, polyvinylamine, chitosan, and neutralized or partially neutralized products thereof with an acid such as hydrochloric acid or acetic acid. it can. Of course, the present invention is not limited to these.

Examples of the anionic compound used in the present invention include polyacrylic acid, polymethacrylic acid, styrene-acrylic acid copolymer, styrene-acrylic acid-acrylic acids, styrene-maleic acid-alkyl acrylate. Examples thereof include an ester copolymer, a styrene-methacrylic acid copolymer, a styrene-methacrylic acid-alkyl acrylate copolymer, alginic acid, polysaccharides such as carboxymethyl cellulose, polyvinyl sulfate, and alkali salts of the above substances. Alkaline salts include alkali metals such as sodium, lithium and potassium,
Examples thereof include ammonium salts, alkylamine salts, and alkanolamine salts. These compounds can be used alone or in an appropriate combination of several types.

A preferable range of various physical properties of each ink constituting the ink set of the present invention is, when the ink contains a cationic substance, a pH of 3 to 12, preferably 3 to 8, The pH is preferably 3 to 5, and when the ink contains an anionic compound, the pH is 5 to 1
2, more preferably 5 to 10. These inks have a surface tension of 10 to 60 dyne / c.
m, more preferably 10 to 40 dyne / cm, and a viscosity of 1 to 30 cps. In addition, each ink constituting the ink set of the present invention is appropriately compounded with additives such as a viscosity adjuster, a pH adjuster, a preservative, a surfactant, an antioxidant, and an evaporation accelerator as needed. It doesn't matter.

Next, as a coloring material constituting the ink set of the present invention, a water-soluble dye or pigment containing an anionic group or a cationic group may be used. The water-soluble dye containing an anionic group that can be used in the present invention is not particularly limited as long as it is a water-soluble acid dye, direct dye, or reactive dye described in the Color index. In addition, there is no particular limitation on those not described in the color index as long as they have an anionic group such as a sulfone group and a carboxyl group. The water-soluble dyes mentioned here naturally include those having a pH dependence of solubility.

Examples of the cationic dye which can be used in the present invention include the following. However, the present invention is not particularly limited to these dyes. As the cationic black dye, for example, As
Trazon Black SW (Bayer), Dia
xryl Black SWR-N liq (Mitsubishi),
Kayacel Black CN (Nippon Kayaku) and the like. As the cationic yellow (Y) dye, for example, C.I. I. Basic Yellow, 11, 13,
19, 28, 29, 33, 36 and the like. Examples of the cationic magenta (M) dye include C.I. I. Ba
sic Red1,2,9,12,13,24,39,
51 and C.I. I. Basic Violet 1, 3,
7, 10, 11, 15, 16, 20, 27, 35, 39
And the like, and as the cationic cyan (C) dye,
For example, C.I. I. Basic Blue 1, 3, 5,
9, 21, 24, 25, 26, 28, 45, 47, 5
4, 65, 92, 100, 124, 147 and the like. For the cationic black dye, the above Y, M
And C by using the cationic dyes C and C to be used for the cationic black ink. In the present invention, the content of the coloring material in the ink as described above is preferably about 0.1 to 15% by weight.

Next, the image forming method of the present invention using the ink set having the above-described configuration will be described. The image forming method according to the present invention uses the ink set having the above-described configuration and uses a plurality of inks. (A) in which an ink is applied to an image forming area or an image forming area on a recording material and the vicinity thereof in the image forming method of forming an image by discharging ink onto a recording material and applying ink to the recording material. (B) attaching ink having a polarity different from that of the ink used in (A) in accordance with a recording signal. The image forming area in the present invention is an area where ink dots are attached, and is separated from the vicinity of the image forming area by about 1 to 5 dots outside the area where the ink dot diameter is attached. Refers to the area.

In the image forming method of the present invention, any ink may be used as long as the inks having different polarities constituting the ink set of the present invention coexist on a recording material such as paper. Therefore, for example, it does not matter which of the ink containing the anionic substance and the ink containing the cationic substance having a different polarity is applied to the recording material first. In addition, the time from when the first ink is first applied to the recording material to when the ink having a different polarity from the previously applied ink is applied onto the recording material is also particularly limited. However, it is preferable that the ink be deposited on the recording material substantially simultaneously or within a few seconds.

The recording material used in the above-described image forming method of the present invention is not particularly limited, and so-called plain paper such as copy paper and bond paper, which is conventionally used, is preferably used. be able to. Of course, a coat specially prepared for ink jet recording or a transparent film for OHP can also be suitably used. Further, general high-quality paper and glossy paper can also be suitably used. Further, as a method of attaching the ink to the image forming area or the image forming area on the recording material and the vicinity thereof, for example, a method of attaching the ink to the entire surface of the recording material by spraying, a roller, or the like can be considered, but more preferably. It is preferable to use an ink jet method in which inks having different polarities can be selectively and uniformly applied to only the image forming area to which the ink adheres, or the image forming area and the vicinity of the image forming area. In this case, various ink jet recording methods can be used, but an ink jet recording method of discharging liquid droplets using bubbles generated by thermal energy is particularly preferable.

Although the ink set of the present invention can be used as a general water-soluble writing instrument, it is particularly suitable when applied to an ink jet recording method of a type in which ink is ejected by a foaming phenomenon of ink by thermal energy. There is a feature that the ejection becomes extremely stable and no generation of satellite dots or the like occurs. However, in this case, it may be necessary to adjust thermal physical properties (for example, specific heat, thermal expansion coefficient, and thermal conductivity).

An ink jet recording method and an ink jet recording apparatus suitable for performing recording using the ink set of the present invention include a method in which thermal energy corresponding to a recording signal is applied to ink in a chamber of a recording head, and the thermal energy is applied to the ink. An ink jet recording method and an ink jet recording apparatus for generating droplets are exemplified. FIGS. 1, 2 and 3 show examples of the configuration of a head which is a main part of the apparatus.

The head 13 shown in FIGS. 1 and 2 includes a glass, ceramic or plastic plate having a groove 14 through which ink passes, and a heating head 15 used for thermal recording.
(Thin film head is shown in the figure, but is not limited to this). Heating head 1
Reference numeral 5 denotes a protective film 16 made of silicon oxide or the like, aluminum electrodes 17-1 and 17-2, a heating resistor layer 18 made of nichrome or the like, a heat storage layer 19, and a substrate 20 having good heat dissipation properties such as alumina. Consists of

The ink 21 has a discharge orifice (fine hole) 2
2, and a meniscus 23 is formed by a pressure (not shown). Now, aluminum electrodes 17-1 and 17
When electric signal information is added to -2, the area indicated by n of the heating head 15 generates heat rapidly, bubbles are generated in the ink 21 in contact with the area, and the meniscus 23 protrudes due to the pressure, and the ink 21 is ejected. As a result, the ink droplets become ink droplets 24 and fly from the ejection orifices 22 toward the recording material 25.

FIG. 3 is an external view of a multi-head in which many heads shown in FIG. 1 are arranged. The multi-head is manufactured by closely contacting a glass plate 27 having a multi-groove 26 and a heating head 28 similar to that described with reference to FIG. FIG. 1 is a cross-sectional view of the head 13 along the ink flow path.
FIG. 2 is a sectional view taken along line AB in FIG.

FIG. 4 shows an example of an ink jet recording apparatus incorporating the above head. In FIG. 4, reference numeral 61 denotes a blade as a wiping member, one end of which is held by a blade holding member to become a fixed end, and forms a cantilever. The blade 61 is arranged at a position adjacent to a recording area of the recording head 65, and in the present example, is held in a form protruding into the movement path of the recording head 65. Reference numeral 62 denotes a cap on the ejection port surface of the recording head 65, which is disposed at a home position adjacent to the blade 61, moves in a direction perpendicular to the moving direction of the recording head 65, and comes into contact with the ink ejection port surface to perform capping. It has a configuration to perform. Further, reference numeral 63 denotes an ink absorber provided adjacent to the blade 61, which is held in a form protruding into the movement path of the recording head 65, similarly to the blade 61.

The blade 61, the cap 62, and the ink absorber 63 constitute an ejection recovery section 64, and the blade 61 and the ink absorber 63 remove water, dust, and the like from the ink ejection port surface. A recording head 65 having ejection energy generating means for ejecting ink to a recording material facing an ejection port surface provided with ejection ports to perform recording;
Reference numeral 6 denotes a carriage on which the recording head 65 is mounted and moved. The carriage 66 is slidably engaged with the guide shaft 67, and a part of the carriage 66 is connected to a belt 69 driven by a motor 68 (not shown). As a result, the carriage 66 can move along the guide shaft 67, and the recording head 65 can move the recording area and the adjacent area.

Reference numeral 51 denotes a paper feed unit for inserting a recording material, and reference numeral 52 denotes a paper feed roller driven by a motor (not shown). With such a configuration, the recording material is fed to a position facing the discharge port surface of the recording head 65, and is discharged to a discharge section provided with a discharge roller 53 as recording proceeds.

In the above configuration, when the recording head 65 returns to the home position at the end of recording or the like, the cap 62 of the ejection recovery section 64 is retracted from the moving path of the recording head 65, but the blade 61 projects into the moving path. I have. As a result, the ejection port surface of the recording head 65 is wiped.
When capping is performed by contacting the cap 62 with the ejection port surface of the recording head 65, the cap 62 moves so as to protrude into the moving path of the recording head.

When the recording head 65 moves from the home position to the recording start position, the cap 62 and the blade 61 are at the same position as the position at the time of wiping described above. As a result, the ejection port surface of the recording head 65 is also wiped during this movement. The movement of the print head 65 to the home position is performed not only at the end of printing or at the time of ejection recovery, but also at the home position adjacent to the printing area at a predetermined interval while the printing head 65 moves through the printing area for printing. And the wiping is performed with this movement.

FIG. 5 is a view showing an example of an ink cartridge containing ink supplied to the head via an ink supply member, for example, a tube. Here, reference numeral 40 denotes an ink storage unit that stores the supply ink, for example, an ink bag, and a rubber stopper 42 is provided at the end thereof. By inserting a needle (not shown) into this stopper 42,
The ink in the ink bag 40 can be supplied to the head. An ink absorber 44 receives the waste ink. In the present invention, it is preferable that the ink absorbing portion has a liquid contact surface with the ink formed of polyolefin, particularly polyethylene.

The ink-jet recording apparatus used in the present invention is not limited to the above-described apparatus in which the head and the ink cartridge are separated from each other, but also preferably the apparatus in which they are integrated as shown in FIG. Used. In FIG. 6, reference numeral 70 denotes a recording unit, in which an ink storage unit storing ink, for example, an ink absorber is stored, and a head unit having a plurality of orifices in which the ink in the ink absorber is stored. It is configured to be ejected from 71 as ink droplets.

As the material of the ink absorber, it is preferable for the present invention to use polyurethane, cellulose or polyvinyl acetate. Reference numeral 72 denotes an atmosphere communication port for communicating the inside of the recording unit with the atmosphere. The recording unit 70 is used in place of the recording head shown in FIG. 4, and is detachable from the carriage 66.

[0037]

Next, the present invention will be described more specifically with reference to examples and comparative examples. In the following description, parts and% are based on weight unless otherwise specified. First, each component described below was mixed, thoroughly stirred and dissolved, and the pore size became 0.4.
Pressure filtration was performed on a 5 μm fluoropore filter (trade name: manufactured by Sumitomo Electric Industries, Ltd.) to prepare inks constituting the ink set of the present invention. In addition, each ink was prepared so as to be 100 parts in total.

Yellow ink 1 (Y1) N-methyl 2-pyrrolidone 10 parts Triethylene glycol monobutyl ether 5 parts Diethylene glycol monoethyl ether 4 parts Direct yellow 86 2 parts Acetyleneol EH (manufactured by Kawaken Chemicals Co., Ltd.) 1 Department / Water Remaining

Yellow ink 2 (Y2) 7 parts of acetamide 3 parts of diethylene glycol C.I. I. Basic Yellow 11 2 parts ・ Ethanol 6 parts ・ Water remainder

Yellow ink 3 (Y3) 10 parts of N-methyl 2-pyrrolidone 5 parts of triethylene glycol monobutyl ether 4 parts of diethylene glycol monoethyl ether 0.5 part of direct yellow 86 Acetylenol EH (manufactured by Kawaken Chemicals Co., Ltd.) 1) ・ Water remaining

Magenta ink 1 (M1) , 7 parts of glycerin, 6 parts of triethylene glycol, 2 parts of Projet Fast Magenta dye (manufactured by Zeneca), 2.5 parts of isopropanol, 2.5 parts of water

Magenta Ink 2 (M2) 7 parts acetamide 5 parts diethylene glycol C.I. I. Basic Red 12 0.5 part ・ Polyallylamine acetate (Mw = 950 manufactured by Nitto Boseki) 2.5 parts ・ Acetyleneol EH (manufactured by Kawaken Chemicals) 1 part ・ Water remaining part

Magenta Ink 3 (M3) , 7 parts glycerin, 6 parts triethylene glycol, 0.4 parts Projet Fast Magenta dye (Zeneca), 2.5 parts isopropanol, 2.5 parts water

Cyan Ink 1 (C1) 4 parts of triethylene glycol 10 parts of N-methyl 2-pyrrolidone I. Direct Blue 199 3 parts ・ Polyacrylic acid polymer Julimer AC-10S (manufactured by Nippon Pure Chemical Co., Ltd.) 1.5 parts ・ Water remaining part

Cyan Ink 2 (C2) 15 parts 2-pyrrolidone Polyallylamine hydrochloride (MW = 10000 manufactured by Nitto Boseki) 2 parts Benzalkonium chloride (manufactured by Sanyo Chemical Industries) 1 part C.I. I. Basic Blue 100 2 copies-Water balance

Cyan Ink 3 (C3) , 4 parts of triethylene glycol, 10 parts of N-methyl 2-pyrrolidone, I. Direct Blue 199 0.6 parts ・ Polyacrylic acid polymer Julimer AC-10S (manufactured by Nippon Pure Chemical Co., Ltd.) 0.5 parts ・ Water remainder

Black ink 1 (Bk1) 10 parts formamide 5 parts glycerin C.I. I. Direct Black 195 2.5 parts ・ C. I. Direct Yellow 86 0.2 parts ・ Isopropyl alcohol 5 parts ・ Polyacrylic acid polymer Julimer AC-10S (manufactured by Nippon Pure Chemical) 1.5 parts ・ Water remainder

Black ink 2 (Bk2) 9 parts glycerin 5 parts urea 3 parts diethylene glycol 3 parts Kayase Black CN (manufactured by Nippon Kayaku) 5 parts 2-propanol 5 parts water

Black Ink 3 (Bk3) 10 parts formamide 5 parts glycerin C.I. I. Direct Black 195 0.8 parts ・ Isopropyl alcohol 5 parts ・ Polyacrylic acid type polymer Julimer AC-10S (manufactured by Nippon Pure Chemical Co., Ltd.) 1.5 parts ・ Water remainder

The inks Y1, M obtained as described above
1, ink set 1 using C1, and Bk1, and ink set 2 using inks Y2, M2, C2, and Bk2.
, An ink set 3 using Y3, M3, C3 and Bk3, an ink set 4 using Y1, M1, C1 and Bk2, and an ink set 5 using Y2, M2, C2 and Bk1. Table 1 shows the configurations of the ink sets 1 to 5.
-1 to Table 1-5 are shown together.

Table 1-1 Configuration of ink set 1

Table 1-2 Configuration of Ink Set 2

Table 1-3 Configuration of Ink Set 3

Table 1-4 Composition of ink set 4

Table 1-5 Configuration of Ink Set 5 Using these ink sets 1 to 5, recording was performed on PPC paper (manufactured by Canon). As the ink jet recording apparatus used at this time, a recording apparatus similar to that shown in FIG. 4 was used, and a color image was formed using the two recording heads shown in FIG.

Example 1 The ink set of this example was constructed using the ink set 1 and the ink set 2, and recording was performed on PPC paper (manufactured by Canon). As the ink jet recording apparatus used at this time, the same recording apparatus as that shown in FIG. 4 was used.
A color image was formed using two recording heads configured as shown in FIG. As a printing method, for example, when printing yellow, the yellow ink of the ink set 1 is first adhered on the recording paper, and then,
Printing was performed by printing the yellow ink of the ink set 2. Printing was performed in the same manner for magenta ink, cyan ink, and black ink. For the colors such as red, blue, and green, first, the ink selected from the ink set 1 was applied first, and then printing was performed by printing the appropriate ink from the ink set 2. The recording head used here had a recording density of 360 dpi, and the driving conditions were a driving frequency of 5 kHz. In addition, heads each having a discharge volume of 45 pl per dot were used. These recording conditions in Example 1 were the same throughout the other Examples and Comparative Examples described below. The environmental conditions for the printing test were also 25 ° C /
The conditions were unified to 55% RH.

Example 2 An ink set of this example was constructed using an ink set 1 having a structure shown in Table 1-1 and an ink set 2 having a structure shown in Table 1-2. A color image was formed using two recording heads configured as described above. At this time, printing and recording were performed in the same manner as in Example 1 except that the ink of the ink set 2 was printed first and then the ink of the ink set 1 was printed.

Example 3 An ink set of this example was constituted by using the ink set 2 having the structure shown in Table 1-2 and the ink set 3 having the structure shown in Table 1-3, and shown in FIG. Is configured as 2
A color image was formed using one recording head. At this time, printing and recording were performed in the same manner as in Example 1 except that the ink of Ink Set 3 was printed before the ink of Ink Set 3 was printed.

Example 4 Using the ink set 4 of the present example having the configuration shown in Table 1-4 using Y1, M1, C1, and Bk2, FIG.
A color image was formed using a recording head configured as shown in FIG. At this time, for example, cyan ink C
1 and then print the black ink Bk2 to form a black image by printing any two types of ink before and after, and apply one or both of the two types of ink. Printing was recorded using a printing process that included a solvent.

Example 5 Using the ink set 4 of the present example having the configuration shown in Table 1-5 using Y2, M2, C2, and Bk1, FIG.
A color image was formed using a recording head configured as shown in FIG. At this time, for example, the cyan ink C1
And then printing black ink Bk2 to form a black image, such as printing two arbitrary inks before and after, and using a solvent in both of the two inks. Printing was recorded using a printing process.

Next, the following components are mixed, sufficiently stirred and dissolved, and filtered under pressure through a fluoropore filter having a pore size of 0.45 μm (trade name: manufactured by Sumitomo Electric Industries, Ltd.). Inks for constituting the ink sets of the comparative examples of the invention were each prepared. Each ink has a total of 10
It was adjusted to be 0 parts.

Yellow ink (Y4) 7 parts hexylene glycol 3 parts diethylene glycol C.I. I. Basic Yellow 11 2 parts ・ Ethanol 6 parts ・ Water remainder

Magenta ink (M4) 7 parts glycerin 6 parts triethylene glycol 2 parts Projet Fast Magenta dye (Zeneca) 2 parts isopropanol 2.5 parts water

Cyan ink (C4) 15 parts pyridine 2 parts polyallylamine hydrochloride (MW = 10000 manufactured by Nitto Boseki) 1 part benzalkonium chloride (manufactured by Sanyo Chemical Industries) 1 part C.I. I. Basic Bull-100 2 parts ・ Water remaining part

Black ink (Bk4) 10 parts cyclohexanol 5 parts glycerin C.I. I. Direct Black 195 2.5 parts ・ C. I. Direct Yellow 86 0.2 parts ・ Isopropyl alcohol 5 parts ・ Polyacrylic acid polymer Julimer AC-10S (manufactured by Nippon Pure Chemical) 1.5 parts ・ Water remainder

Yellow ink (Y5) 5 parts triethylene glycol monobutyl ether 4 parts diethylene glycol monoethyl ether 2 parts direct yellow 86 1 part acetylenol EH (manufactured by Kawaken Chemicals Co.) 1 part water

Magenta ink (M5) 7 parts pyridine 5 parts diethylene glycol C.I. I. Basic Red 12 0.5 parts ・ Polyallylamine acetate (MW = 950, manufactured by Nitto Boseki) 1.5 parts ・ Acetyleneol EH (manufactured by Kawaken Chemicals) 1 part ・ Water remaining part

Cyan ink (C5) 4 parts of triethylene glycol 10 parts of cyclohexane C.I. I. Direct Blue 199 3 parts ・ Polyacrylic acid polymer Julimer AC-10S (manufactured by Nippon Pure Chemical Co., Ltd.) 1.5 parts ・ Water remaining part

Black ink (Bk5) 9 parts glycerin 5 parts urea 3 parts diethylene glycol 3 parts Kayase Black CN (manufactured by Nippon Kayaku) 3 parts 2-propanol 5 parts water

Comparative Example 1 An ink set 6 was formed using the above-described inks Y4, M4, C4 and Bk4, and an ink set 7 was formed using the inks Y5, M5, C5 and Bk5. Ink set 6
Tables 1-6 and 1-7 collectively show the configurations of Tables 1 and 2. Then, print recording was performed under the same configuration and conditions as in Example 1 except that the ink set 6 was first printed and then the ink set 7 was printed.

Comparative Example 2 An ink set 6 was formed using inks Y4, M4, C4 and Bk4, and an ink set 7 was formed using Y5, M5, C5 and Bk5. Example 1 except that the ink set 6 was printed.
Printing was performed under the same configuration and conditions as in the above.

Table 1-6 Configuration of Ink Set 6

Table 1-7 Configuration of Ink Set 7

(Evaluation Method and Evaluation Criteria) (1) Character Quality In Examples 1 to 3, Bk1 and Bk2 are overprinted, and in Examples 4 and 5, cyan ink is underprinted. The black alphanumeric characters were printed by using a printing process of printing black ink from the following table, and were visually evaluated according to the following criteria. Table 2 shows the evaluation results. A: Feathering is hardly noticeable. ：: Feathering is somewhat conspicuous, but at a level that does not pose any practical problems. ×: Feathering is conspicuous.

(2) Evaluation of water resistance Bk was printed by the same printing process as in (1), alphanumeric characters and solid portions were printed on a commercially available acidic paper, and then printing was stopped. After standing for more than an hour, the print density was measured using a Macbeth RD915 (trade name: manufactured by Macbeth). After that, the printed matter is immersed in a container filled with water for 3 minutes or more, left to dry naturally, the print density is measured again, and the residual ratio of the print density is determined as follows. The properties were evaluated, and Table 2 shows the evaluation results. A: The print density remaining ratio is 80% or more to 100% or more. ：: The print density remaining ratio is 70% or more to 80% or more. X: The print density remaining rate is 70% or less.

(3) Bleeding Canon Color Bubble Jet Printer BJC60
In 1 pass unidirectional printing using 0J, solid portions of inks of each color of yellow, magenta, cyan and black are printed adjacent to each other, and the degree of bleeding at the boundary of each color is visually observed. Table 2 shows the evaluation results. A: Almost no bleeding occurred. ：: Bleeding has occurred slightly, but at a level that has substantially no problem. X: The occurrence of bleeding can be immediately visually recognized.

(4) Evaluation of printing quality after continuous printing The printer performs continuous solid printing in a constant temperature bath at 35 ° C. for 10 sheets, wiping the head face surface once per sheet, and then checking the printing quality. It was observed visually and evaluated according to the following criteria. Table 2 shows the evaluation results. A: Normal printing can be performed. ：: Although there is slight disturbance in printing, printing can be performed without any problem in actual use. X: Non-discharge or printing disorder.

Table 2: Evaluation results

[0079]

As described above, according to the present invention,
A highly reliable ink set that can form an image with excellent print quality even when performing continuous printing, and has excellent water resistance and print quality with respect to plain paper, and has no problem with bleeding. Provided are an inkjet recording method, an inkjet recording apparatus, and equipment.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a head of an ink jet recording apparatus.

FIG. 2 is a cross-sectional view of a head of the inkjet recording apparatus.

FIG. 3 is an external perspective view of a head obtained by multiplying the head shown in FIG. 1;

FIG. 4 is a perspective view illustrating an example of an ink jet recording apparatus.

FIG. 5 is a vertical sectional view of the ink cartridge.

FIG. 6 is a perspective view illustrating an example of a recording unit.

FIG. 7 is an explanatory diagram illustrating a configuration example of a recording head.

FIG. 8 is an explanatory diagram illustrating a configuration example of a recording head.

FIG. 9 is an explanatory diagram illustrating a configuration example of a recording head.

FIG. 10 is an explanatory diagram illustrating a configuration example of a recording head.

FIG. 11 is an explanatory diagram illustrating a configuration example of a recording head.

[Explanation of symbols]

 13: Head 14: Ink groove 15: Heating head 16: Protective film 17-1, 17-2: Aluminum electrode 18: Heating resistor layer 19: Heat storage layer 20: Substrate 21: Ink 22: Discharge orifice (fine hole) 23 : Meniscus 24: ink droplet 25: recording medium 26: multi-groove 27: glass plate 28: heat generating head 40: ink bag 42: stopper 44: ink absorber 45: ink cartridge 51: paper feed unit 52: paper feed roller 53: paper discharge roller 61: blade 62: cap 63: ink absorber 64: ejection recovery unit 65: recording head 66: carriage 67: guide shaft 68: motor 69: belt 70: recording unit 71: head unit 72: atmosphere communication mouth

Continuation of the front page (72) Inventor Yoichi Takada 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc.

Claims (32)

[Claims] 1. An ink set comprising a combination of a plurality of inks used to form an image by ejecting ink onto a recording material and attaching a plurality of inks,
The ink set has at least two kinds of inks having different polarities, and a solvent for re-dissolving a reactant generated by the two kinds of inks having different polarities is one or both of the two kinds of inks. An ink set characterized by being included in any one of the above. 2. The ink set according to claim 1, wherein the ink ejected first of the two types of ink contains a cationic compound, and the ink ejected after the other contains an anionic compound. . 3. The ink set according to claim 1, wherein the ink ejected first of the two inks contains an anionic compound, and the ink ejected after the other contains a cationic compound. . 4. The ink set according to claim 1, wherein the ink ejected first of the two types of ink contains a cationic dye. 5. The ink set according to claim 1, wherein the ink ejected first of the two types of ink contains a cationic compound and a cationic dye. 6. The ink set according to claim 1, wherein the ink ejected after the two kinds of inks contains a cationic dye. 7. The ink set according to claim 1, wherein the ink ejected after the two kinds of inks contains a cationic compound and a cationic dye. 8. The ink set according to claim 1, wherein the ink ejected first of the two types of ink contains an anionic dye. 9. The ink set according to claim 1, wherein the ink ejected first of the two kinds of inks contains an anionic compound and an anionic dye. 10. The ink set according to claim 1, wherein the ink ejected after the two kinds of inks contains an anionic dye. 11. The ink set according to claim 1, wherein the ink ejected after the two kinds of inks contains an anionic compound and an anionic dye. 12. An image forming method for forming an image by ejecting a plurality of inks onto a recording material and adhering the inks using the ink set according to any one of claims 1 to 11. A step (A) of applying ink to an image forming area or an image forming area on a recording material and its vicinity, and a step (B) of applying ink having a polarity different from that of the ink used in step (A) in accordance with a recording signal. An image forming method comprising: 13. The image forming method according to claim 12, wherein the adhesion of the ink in the step (B) is performed by an ink jet recording method. 14. The method according to claim 1, wherein the adhesion of the ink to the recording material in the step (A) is performed by an ink jet recording method.
3. The image forming method according to item 2. 15. The image forming method according to claim 12, wherein the step (A) is performed prior to the step (B). 16. The image forming method according to claim 12, wherein the step (A) is performed after the step (B). 17. Performing the step (A) after the step (B),
The image forming method according to claim 12, wherein the step (B) is further performed thereafter. 18. An ink jet recording method in which ink droplets are ejected from an orifice according to a recording signal to perform recording on a recording material, wherein the ink is the ink set according to claim 1. Method. 19. The ink-jet recording method according to claim 18, wherein the ink is ejected by applying thermal energy to the ink. 20. An ink set according to claim 1, wherein in a recording unit comprising an ink containing section containing ink and a head section for discharging the ink as ink droplets, the ink is the ink set according to claim 1. Recording unit. 21. A head for ejecting ink droplets by applying thermal energy to the ink.
The recording unit according to 0. 22. The recording unit according to claim 20, further comprising an ink absorber inside the ink containing section. 23. The recording unit according to claim 20, wherein the ink containing section is formed of polyurethane, cellulose, or polyvinyl acetate. 24. An ink cartridge provided with an ink containing section containing ink, wherein the ink is provided.
An ink cartridge, which is the ink set described in (1). 25. The ink cartridge according to claim 24, wherein the ink container has a liquid contact surface formed of polyolefin. 26. An ink jet recording apparatus comprising: a recording unit having an ink storage section for storing ink and a head section for discharging the ink as ink droplets, wherein the ink is the ink set according to claim 1. An ink jet recording apparatus, comprising: 27. A head for ejecting ink droplets by applying thermal energy to the ink.
7. The ink jet recording apparatus according to 6. 28. The ink jet recording apparatus according to claim 26, wherein the ink containing section contains the ink containing section inside. 29. The ink jet recording apparatus according to claim 26, wherein the ink container is formed of polyurethane, cellulose, or polyvinyl acetate. 30. An ink jet recording method comprising: a recording head for ejecting ink droplets; an ink cartridge having an ink container containing ink; and an ink supply unit for supplying ink from the ink cartridge to the recording head. An ink jet recording apparatus, wherein the ink is the ink set according to claim 1. 31. The ink jet recording apparatus according to claim 30, wherein the recording head is a head for ejecting ink droplets by applying thermal energy to ink. 32. The ink jet recording apparatus according to claim 30, wherein the ink containing section has a liquid contact surface formed of polyolefin.