JPH11192687A - Method and device for forming image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming method for forming an image having the sufficient density and good character quality level. SOLUTION: Droplets are jetted out of a jet opening of a head of S tip 2201S jetting a liquid making a coloring material in ink insoluble or coagulated while moving in the arrow mark X direction. Successively a first black ink drop is jetted out of a jet opening of a head of a BK tip 2201BK jetting black ink on an area on which the droplet referred in the preceding sentence is jetted. Then a second ink drop is jetted on the same area while moving in the arrow mark Y direction. The jet amount of the second ink drop can be more than the jet amount of the first ink drop.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming method, particularly to a liquid composition and an ink set used for an image forming method suitable for an ink jet recording system, and an image forming method using the same. More specifically, after attaching a colorless or light-colored liquid composition to a recording medium, an ink containing at least a dye having an anionic group or a pigment dispersed with an anionic substance is mixed with the colorless or light-colored liquid composition. The present invention relates to a liquid composition, an ink set, and an image forming method and an image forming apparatus using the liquid composition, which are used when recording is performed by attaching to an area where an object is attached or in the vicinity thereof.

[0002]

2. Description of the Related Art In an ink-jet recording method, recording is performed by flying small ink droplets and depositing ink on a recording medium such as paper. In particular, Japanese Patent Publication No. 61-59911
No., JP-B-61-59912, JP-B-69-59
According to the method disclosed in Japanese Patent Application Laid-Open No. 914, in which a thermal energy is applied to an ink using an electrothermal converter as an ejection energy supply means to generate ink bubbles to eject station drops, the height of the recording head is reduced. The density multi-orifice can be easily realized, and high-resolution and high-quality images can be recorded at high speed.

However, inks used in conventional ink-jet recording generally contain water as a main component and generally contain a water-soluble high-boiling solvent such as glycol for the purpose of preventing drying and clogging. When recording on plain paper using such inks, non-uniform images may be obtained, which may not be able to achieve sufficient fixation or may be presumed to be due to the non-uniform distribution of the sizing agent or the amount of the recording paper surface. Was. Also, especially when trying to obtain a color image, since the inks of multiple colors are successively superimposed before being fixed on the paper, the colors are blurred or unevenly mixed at the boundary of the images of different colors, Bleeding occurred, and a satisfactory image was not obtained.

On the other hand, as a means for improving the fixing property, Japanese Patent Application Laid-Open No. 55-65269 discloses a method of adding a compound for improving the permeability such as a surfactant to the ink. Japanese Patent Application Laid-Open No. 55-66976 discloses the use of an ink mainly containing a volatile solvent.

However, in the former method of adding a surfactant or the like to the ink, the permeability of the ink to the recording paper is increased, and although the ink fixing property and bleeding are somewhat effective, the coloring material of the ink is not used. Also penetrates deep into the recording paper, causing problems such as a reduction in image density and saturation. Further, the ink also spreads in the horizontal direction, and as a result, problems such as a decrease in sharpness of an edge and a decrease in resolution also occurred.

On the other hand, in the case of the latter method using an ink mainly composed of a volatile solvent, the same disadvantages as those in the former case occur. Clogging easily occurred, which was not preferable.

Further, in order to solve the above-mentioned problem,
Prior to the ejection of ink, a method has been proposed in which a liquid for favorably forming an image on a recording medium is applied in advance. For example, JP-A-63-2999971 discloses that
A method is disclosed in which a liquid containing an organic compound having two or more cationic groups per molecule is deposited on a recording medium, and then recording is performed with an ink containing an anionic dye. JP-A-64-9279 discloses a method in which an acidic liquid containing succinic acid or the like is deposited on a recording medium, and recording is performed with an ink containing an anionic dye. Furthermore, Japanese Patent Application Laid-Open No. 63-63185 discloses a method in which a liquid for insolubilizing a dye is applied prior to recording.

[0008]

However, in any of the above methods, the bleeding of the image is prevented by the precipitation of the dye itself,
In order to improve the water resistance of the image, the effect of suppressing the bleeding between the color inks described above is insufficient, and the recording paper is configured because the precipitated dye is likely to be unevenly distributed on the recording paper. The pulp fiber to be coated has a poor coverage and the uniformity of the image is reduced.

Accordingly, the present invention has been made in view of the above circumstances to solve the following problems. That is, when performing inkjet recording on plain paper,
(1) Sufficient image density is obtained and solid image uniformity is high. (2) Character quality is good while having good fixability.

[0010]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that the above problems can be solved by using the following means. That is, the present invention relates to an ink jet recording method in which a treatment liquid is applied in accordance with a recording image and recording is performed.
It is characterized in that recording ink droplets of the same color forming pixels are ejected at least twice.

According to such a configuration, the ejection of ink droplets of the same color forming one pixel is divided into a plurality of shots, so that the sharpness of the edges of the recording dots and the high image quality can be obtained while maintaining good fixability. It is possible to obtain a concentration.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The processing solution used in the present invention is: 1. Improve the water resistance of recorded images. 2. Improve the print quality of the recorded image. There is no limitation as long as it has a function of reducing the blur of a different color boundary between different colors of a recorded image.
When the kind of cationic substance is contained in the treatment liquid, the above-mentioned effect can be exerted.

The cationic substance is not particularly limited as long as it has a cationic group in the molecule. Examples thereof include an aqueous acid solution, an inorganic metal salt, a cationic surfactant, a cationic oligomer and a polymer. preferable.

First, the aqueous acid solution includes an aqueous hydrochloric acid solution.

Preferred examples of the inorganic metal salt include polyvalent metal salts such as calcium chloride, aluminum chloride, barium chloride, nickel chloride, magnesium chloride, and aluminum hydroxide. Preferred specific examples of the cationic surfactant include compounds of salts of primary to secondary and tertiary amines, specifically, hydrochlorides such as laurylamine, cocoamine, stearylamine and rosinamine; Compounds of the quaternary ammonium type, specifically, cetyltrimethylammonium chloride, lauryltrimethylammonium chloride, lauryldimethylbenzylammonium chloride, benzyltributylammonium chloride,
Benzalkonium chloride and the like; amphoteric surfactants exhibiting cationicity in a certain PH region, specifically, amino acid-type amphoteric surfactants, betaine-type compounds, etc. adjusted to have an isoelectric point or less, and of course, these However, the present invention is not limited to this.

Among these compounds, the fourth compound
A quaternary ammonium type compound is preferred.

Next, specific monomer units of cationic oligomers and polymers include vinylamine, allylamine, vinylpyridine, vinylimidazole, N, N-dimethylaminoacrylamide, ethyleneimine, 2-oxazoline and the like. However, of course, it is not limited to these.

In addition to the above-mentioned homopolymer of a cationic monomer unit, a copolymer of the cationic monomer unit and a nonionic monomer unit, a part of a nonionic oligomer or a polymer may be used. There is no problem even if it is polymerized.

Among these compounds, oligomers and polymers containing allylamine as a unit are particularly preferable.

Further, when a low molecular weight cationic surfactant and polyallylamine are used in combination, it is possible to reduce bleeding of a different color boundary at the time of color recording. .

Next, other components used in the present invention will be described.

In the present invention, for example, a water-soluble dye is used as a coloring material of an ink for recording a color to which a treatment liquid is applied. A water-soluble dye having an anionic group as a solubilizing group is used. The ink used in the present invention further includes water, a water-soluble organic solvent, and other components such as a viscosity modifier, a pH regulator, a fungicide, a neutral or anionic surfactant, and an antioxidant. Agents and the like are included as needed.

In the present invention, the color of the ink for recording the color to which the treatment liquid is applied is black, cyan, magenta, or yellow, and examples of the coloring material include an anionic water-soluble dye.

The water-soluble dye having an anionic group used in the present invention includes a color index (COLOUH).
R INDEX), water-soluble acid dyes described in
There is no particular limitation as long as it is a direct dye or a reactive dye. Also,
There is no particular limitation on dyes not described in the color index as long as they have an anionic group, for example, a sulfone group. These dyes are used in the ink in the range of 1 to 10% by weight, preferably 1 to 5% by weight.

Specific dyes include C.I. I. Direct Yellow 8, 11, 12, 27, 28, 33, 3
9,44,50,58,85,86,87,88,8
9, 98, 100, 110 C.I. I. Direct Red 2,4,9,11,20,
23, 24, 31, 39, 46, 62, 75, 79, 8
0,83,89,95,197,201,218,22
0,224,225,226,227,228,230 C.I. I. Direct Blue 1,15,22,25,4
1,76,77,80,86,90,98,106,1
08,120,158,163,168,199,22
6 C. I. Acid Yellow 1,3,7,11,17,
23, 25, 29, 36, 38, 40, 42, 44, 7
6,98,99 C.I. I. Acid Red 6,8,9,13,14,1
8, 26, 27, 32, 35, 42, 51, 52, 8
0, 83, 87, 89, 92, 106, 114, 11
5,133,134,145,158,198,24
9,265,289 C.I. I. Acid Blue 1,7,9,15,22,2
3,25,29,40,43,59,62,74,7
8,80,90,100,102,104,117,1
27, 138, 158, 161 C.I. I. Direct Black 17,19,22,3
1, 32, 51, 62, 71, 74, 112, 113,
154,168 C.I. I. Acid Black 2,48,51,52,1
10, 115, 156 C.I. I. Reactive Black 1,8,12,13 C.I. I. Food Black 1, 2 and the like.

In addition to the above, examples of the coloring material of the ink for recording colors used in the present invention include: Dyes having a carboxyl group as a solubilizing group This includes dyes that show solubility dependence on pH.

2. Oil-soluble dye 3. cationic dye Pigments and the like can also be used.

When the ink containing these coloring materials comes into contact with the ink containing the water-soluble anionic dye for applying the treatment liquid, the ink does not bleed at the boundary because of precipitation at the boundary and incompatibility with each other. Therefore, it is desirable.

In particular, 1. , 2. , 4. Many coloring materials having excellent water resistance are particularly desirable.

Examples of the dye having a carboxyl group include the following compounds 1 (formula 1), 2 (formula 2),
Compound 3 (Chemical Formula 3) and Compound (Chemical Formula 4) are exemplified, but of course, the present invention is not limited to dyes having these structures.

Compound 1

[0032]

Embedded image

Compound 2

[0034]

Embedded image

Compound 3

[0036]

Embedded image

Compound 4

[0038]

Embedded image

The oil-soluble dye is not particularly limited as long as it is described in the color index (COLOUR INDEX). Also, there is no particular limitation on a novel dye not described in the color index.

Specifically, C.I. I. Solvent blue
33, 38, 42, 45, 53, 65, 67, 70, 1
04, 114, 115, 135, C.I. I. Solvent Red 25, 31, 86, 92, 97, 118, 13
2,160,186,187,219, C.I. I. Solvent Yellow 1,49,62,74,79,82,8
3,89,90,120,121,151,153,1
54 and the like.

The cationic dye is not particularly limited as long as it is described in the color index (COLOUR INDEX). Also, there is no particular limitation on a novel dye not described in the color index.

Specifically, C.I. I. Basic Black 2,8 Aizen Cathilon Black SBH,
BXH, SH, ACH, MH, TH (manufactured by Hodogaya Chemical) Sumiacryl Black B, R, AP, B
P, CP, FFP (Sumitomo Chemical) Diacryl Supra Black GSL, R
SL, ESL (Mitsubishi Chemical) C.I. I. Basic Yellow 1,11,13,19,
25, 33, 36 C.I. I. Basic Red 1,2,9,12,13,
38, 39, 92 C.I. I. Basic Blue 1,3,5,9,19,2
4, 25, 26, 28, 45, 54, 65, 75 and the like.

The pigment used in the present invention includes:
Specifically, carbon black is used as a black ink, for example, furnace method,
A carbon black produced by a channel method, having a primary particle diameter of 15 to 40 μm, a specific surface area of 50 to 300 m ₂ / g by a BET method, and a DBP oil absorption of 40 to 150 m.
1/100 g, volatile content 0.5-10%, pH value 2
Those having characteristics such as 9 are preferably used. As a commercially available product having such characteristics, for example, 23
00, No. 900, MCF88, No. 33, no.
40, no. 45, no. 52, MA7, MA8, N
o. 2200B (Mitsubishi Kasei), RAVEN12
55 (all made in Colombia), REGAL400R, R
EGAL330R, REGAL660R, MOGUL
L (above, made by Cabot), Color Black
FW1, COLOR Black FW18, Colo
rBlack S170, Color Black S
150, Printex 35, Printex U (all manufactured by Degussa) and the like, and any of them can be preferably used.

Examples of the pigment used in the yellow ink include C.I. I. Pigment Yellow
ow 1, C.I. I. Pigment Yellow
2, C.I. I. Pigment Yellow 3, C.I.
I. Pigment Yellow 13, C.I. I. P
pigment yellow 16, C.I. I. Pigm
ent Yellow 83 and the like. Examples of the pigment used in the magenta ink include C.I. I. P
Pigment Red 5, C.I. I. Pigment
Red 7, C.I. I. Pigment Red 12,
C. I. Pigment Red 48 (Ca), C.I.
I. Pigment Red 48 (Mn), C.I. I.
Pigment Red 57 (Ca), C.I. I. Pi
gmentRed 112, C.I. I. Pigment
Red 122 and the like. Examples of the pigment used for the cyan ink include C.I. I. Pigment
Blue 1, C.I. I. Pigment Blue
2, C.I. I. Pigment Blue 3, C.I. I. P
Pigment Blue 15: 3, C.I. I. Pigm
ent Blue 16, C.I. I. Pigment B
lue 22, C.I. I. Vat Blue 4, C.I.
I. Vat Blue 6 and the like, but are not limited thereto. In addition to the above, it is of course possible to use pigments newly produced for the present invention.

As a dispersant contained in the ink when a pigment is used, any water-soluble resin can be used.
Those having a range of 3,000 to 30,000 are preferable, and those having a range of 3,000 to 15,000 are more preferably used. Specific examples of such dispersants include styrene, styrene derivatives, vinyl naphthalene, vinyl naphthalene derivatives, aliphatic alcohol esters of α, β-ethylenically unsaturated carboxylic acids, acrylic acid, acrylic acid derivatives, and maleic acid. , Maleic acid derivatives, itaconic acid, itaconic acid derivatives, fumaric acid, fumaric acid derivatives, vinyl acetate, vinylpyrrolidone, acrylamide, derivatives thereof, and the like (at least one of which is at least one Hydrophilic monomer)
Or a random copolymer, a graft copolymer, or a salt thereof. Alternatively, natural resins such as rosin, gelac and starch can also be preferably used. These resins are soluble in an aqueous solution in which a base is dissolved, and are alkali-soluble resins. The water-soluble resin used as the pigment dispersant is 0.1 to 5 parts by weight based on the total weight of the ink.
It is preferable to contain it in the range of weight%.

In particular, in the case of an ink containing the above-described pigment, it is preferable that the entire ink is adjusted to be neutral or alkaline. Such a composition is preferable because the solubility of a water-soluble resin used as a pigment dispersant can be improved, and an ink having more excellent long-term storage properties can be obtained. However, in this case, it may cause corrosion of various members used in the ink jet recording apparatus. Therefore, it is preferable that the pH range be 7 to 10.

The pH adjusting agent used at this time includes
Examples thereof include various organic amines such as diethanolamine and triethanolamine, inorganic alkali agents such as hydroxides of alkali metals such as sodium hydroxide, lithium hydroxide and potassium hydroxide, organic acids and mineral acids. The water-soluble resin as a pigment and a dispersant as described above is dispersed or dissolved in an aqueous liquid medium.

These dyes and pigments are contained in the ink in an amount of 1 to 10%.
%, Preferably in the range of 1 to 5% by weight.

(Embodiment 1) Hereinafter, the present invention will be described in more detail with reference to FIG. This embodiment is an example described for the purpose of facilitating the understanding of the present invention,
The present invention is not particularly limited.

FIG. 1 is a perspective view of an ink jet recording apparatus applicable to the present invention. The recording medium 106 as a recording medium inserted into the paper feeding position of the recording apparatus 100 is conveyed by a feed roller 109 to a recordable area of the recording head unit 103. A platen 108 is provided below the recording medium in the recordable area. Carriage 1
Numeral 01 is configured to be movable in a direction determined by the guide shaft 104 and the guide shaft 105, and performs reciprocal scanning of the recording area. The carriage 101 is equipped with a printhead that discharges a plurality of colors of ink and processing liquid, and a printhead unit 103 that includes an ink tank that supplies ink and processing liquid to each printhead. The plurality of colors of ink provided in the ink jet recording apparatus of this example are four colors of black (Bk), cyan (C), magenta (M), and yellow (Y).

At the left end of the area where the carriage 101 can move, there is a recovery unit 110 at the bottom, and the ejection port of the recording head is capped during non-printing. This left end is called the home position of the recording head.

Reference numeral 107 denotes a switch unit and a display element unit.
The switch unit is used for turning on / off the power of the recording apparatus, setting various recording modes, and the like, and the switch unit plays a role of displaying the state of the recording apparatus.

FIG. 2 is a perspective view of the recording head unit 103. In this example, the inks of black, cyan, magenta, and yellow, and the processing liquid tank are all independently replaceable.

A recording head 102 for discharging Bk, C, M, and Y and a processing liquid, a tank 2 for Bk,
A tank 20C for 0K, C, a tank 20M for M, a tank 20Y for Y, and a tank 2S for processing liquid are mounted. Each tank is connected to the print head via a connection to the print head, and supplies ink and a processing liquid to the discharge ports.

Other than this example, for example, the tank for the processing liquid and the tank for Bk may have an integral structure, and the tanks for C, M and Y may have an integral structure.

FIG. 3 is an enlarged sectional view showing the vicinity of a heating element as a thermal energy generator of the recording head. The ink jet recording apparatus of this example is a recording method in which a heating element, which is an electrothermal converter, is arranged corresponding to each ink ejection port, and a driving signal corresponding to recording information is applied to the heating element to eject ink from a nozzle. Is adopted. The heating element 30 is configured to be capable of generating heat independently for all nozzles.

The ink in the nozzle, which has been rapidly heated by the heat generated by the heating element 30, forms bubbles by film boiling, and the ink droplets 35 are ejected toward the recording medium 31 as shown in FIG. Then, characters and images are formed on the recording medium. At this time, the volume of each color ink droplet to be ejected is 15 to 80 ng.

Each of the discharge ports 37 is provided with an ink liquid path 38 communicating with the discharge port 37, and the ink is supplied to these liquid paths behind the portion where the ink liquid path 38 is provided. A common liquid chamber 32 is provided. An ink liquid path 38 corresponding to each of the discharge ports 37 has a heating element 30 which is an electric-heat converter that generates heat energy used for discharging ink droplets from these discharge ports 37 and an electric power supplied to the heat element 30. An electrode wiring (not shown) for supplying is provided. The heating element 30 and the electrode wiring are formed on a substrate 33 made of silicon or the like by a known film forming technique. A protective film 36 is formed on the heating element 30 so that the ink does not directly contact the heating element. Further, the discharge port 37, the ink liquid path 38, the common liquid chamber 32, and the like are formed by laminating a partition wall 34 made of a resin or a glass material on the substrate 33.

The recording system using the heating element 30 is generally called a bubble jet recording system because it uses bubbles formed by applying thermal energy when ejecting ink droplets.

FIG. 4 shows a color head unit used in this embodiment. The unit configuration includes an S (processing liquid) chip 2201 as a discharge head and a Bk chip 2202
, A C chip 2203, an M chip 2204, and a Y chip 2205 are fixed to a frame 2206. The distance between the chips is 1/2 inch, and the chips are arranged at regular intervals in the direction of X, which is the main scanning direction. Each chip has 128 nozzles, and the nozzle rows of each chip are arranged so as to be substantially orthogonal to the arrow X direction.

The pitch of each nozzle is about 70 μm,
A band for 128 nozzles can be recorded by one main scan at a resolution of 60 dpi.

From each nozzle of the nozzle array of the color chip, for example, by adjusting the pulse width, the ejection amount becomes about 80 p.
3, 40 pl and 26.7 pl are ejected, and about 40 nozzles are provided from each nozzle of the nozzle array of the S chip.
pl of ink is ejected.

In the case of using a recording head having the configuration shown in FIG. 4, first, when the carriage is moving in the direction of the arrow X, an S-chip head is formed in an area where one pixel is formed on the recording. Droplets of the liquid composition are discharged from predetermined discharge ports, and then black ink droplets are discharged from the predetermined discharge ports of the head of the Bk chip so as to overlap the same area.
Thereafter, when the carriage is moving in the direction of the arrow X, black ink droplets are ejected from the head of the Bk chip so as to overlap the same area. Here, when the carriage changes the moving direction from the arrow X direction to the arrow Y direction, the recording paper is moved to the arrow X direction.
Alternatively, when the first black ink droplet is conveyed by, for example, one line pitch in the sub-scanning direction orthogonal to the Y direction, the second black ink droplet is shifted from the first black ink droplet by one line pitch to a different ejection port into the same area. It is controlled so as to be discharged toward. When the moving direction of the carriage changes without being carried in the sub-scanning direction, the two black ink droplets are controlled so as to be ejected from the same ejection port.

The first black ink droplet amount (discharge amount: Vd ₁ ) and the second black ink droplet amount (discharge amount: Vd ₂ ) satisfy the relationship of Vd ₁ ≦ Vd ₂ . When Vd ₁ > Vd ₂ , there is an inconvenience that the image density is lower and the character quality is lower than when Vd ₁ ≦ Vd ₂ . However, the decrease in image density in this case is relatively better than when the liquid composition is not applied.

In order to change the discharge amount in this manner, for example, a so-called double heater or double pulse technique can be used. The method using the double heater uses a head including one ejection port, a fluid path communicating with the ejection port, and two heaters disposed in the fluid path, and when ejecting a small ejection amount of ink droplet, only one of the ejection ports is used. In the case where a heater is driven to discharge a large amount of ink droplets, both heaters are simultaneously driven. The double pulse method uses a head including only one heater in one liquid path, applies a pre-pulse to the heater before an impulse applied during actual ink ejection, and controls the pre-pulse to control the heater. This is a method of adjusting the temperature in the vicinity and the ink and ejection amount when the main pulse is applied.

In the above description, the ink droplet is divided into two and ejected. However, the present invention is not limited to dividing the ink droplet into two, and the ink droplet is divided into three or more and ejected. You may. In this case, the ejection amount of the _first ink droplet is Vd ₁ , the ejection amount of the second ink droplet is Vd ₂ ,
Assuming that the _third ink droplet is Vd ₃ and the ejection amount of the N-th (N ≧ 4) ink droplet is Vd _N , the following equation is obtained.

[0067]

It is necessary to satisfy Vd ₁ ≤Vd ₂ ≤Vd ₃ ≤ ... ≤Vd _N. Vd ₁ > Vd ₂ > Vd ₃ >...> V
Even when the d _N, as compared with the case of _{Vd 1 ≦ Vd 2 ≦ Vd 3} ≦ ... ≦ Vd N, decrease in image density, disadvantageously have the character quality deterioration occurs. However, the decrease in image density in this case is relatively better than when the liquid composition is not applied.

In the case where ink droplets are ejected on the same recording medium in a divided manner, after the liquid composition is ejected, for example, a region for ejecting the liquid composition in two and a region for ejecting in N are mixed. Then, the expression Vd ₁ + Vd ₂ = Vd ₁ + Vd ₂
+ ... Vd _N must be satisfied. This is because if the total amount of ink ejection differs for each region, cockling occurs on the recording medium, and it becomes difficult to form a high-quality image. However, Vd ₁ + Vd ₂ = Vd ₁ + Vd ₂ +... Vd _N = Vto
tal, Vtotal is Vtotal2 × V of the embodiment.
(Liquid composition). That is, the total ink ejection amount does not need to be twice the ejection amount of the liquid composition.

In preparing the following liquid composition and ink composition, the total amount of the liquid composition and the ink composition was set to 100 parts.

(Liquid composition 1) PAA-HCL-1L (trade name, manufactured by Nitto Boseki) 4 parts Diethylene glycol 10 parts Water 86 parts (Liquid composition 2) CaCl ₂ 2 parts Diethylene glycol 10 parts Water 88 parts (Liquid composition) 3) Pentaethylenehexamine 7 parts PAA-HCl-1L (trade name, manufactured by Nitto Boseki) 1 part Diethylenegluicol 10 parts Water 82 parts (Ink composition 1) FB2 (dye) 2 parts Thiodiglycol 7.5 parts Isopropyl 4 parts of alcohol 86.5 parts of water After sufficiently stirring the liquid compositions 1 to 3 and the ink composition 1, the mixture was filtered under pressure through a Fluoropore filter (trade name: Sumitomo Electric) having a pore size of 0.22 μm, and ink and A liquid composition was obtained.

(Toner 1) Mitsubishi Carbon Black # 960 20 parts Styrene acrylate ethyl acrylate 18 parts (acid value 140, molecular weight 5100, 15% aqueous solution, adjusted to pH 9.5 with monoethanolamine) ethylene glycol 6 parts water 144 parts The above components (parts by weight) were mixed, subjected to a dispersion treatment using a sand grinder, and further subjected to stretching and separation to remove coarse particles, thereby obtaining a toner 1.

(Ink Composition 2) Toner 1 50 parts Glycerin 10 parts Thiodiglycol 7 parts Ethanol 4 parts Water 29 parts The above components were mixed to obtain Ink Composition 2.

From each nozzle of the nozzle array of the color chip, for example, by adjusting the pulse width, about 80 pl, 40 p
l, 26.7 pl of ink are ejected, and
About 40 pl of ink is ejected from each nozzle of the nozzle array of the S chip.

The area where the liquid composition adheres to the recording medium is the same area as the image forming area of the ink, and the printing duty is 100% for all of the colorless liquid composition and the ink.

Using the above liquid composition and ink composition (black ink), solid patches were printed by the combinations and printing methods shown in Table 1, and Examples 1 to 8 and Comparative Examples 1 to
And 8.

[0076]

[Table 1]

The image of the printed matter obtained by the printing method shown in Table 1 was evaluated based on the following criteria (1) and (2), and the results are shown in Table 2.

(1) Image Density Using a colorless liquid composition and black ink, a solid patch was printed, and after standing for one day, the reflection density of the printed area was measured using a Macbeth RD-918 reflection densitometer. .

(2) Character Quality Using the liquid composition and black ink, black alphanumeric characters were printed and evaluated visually. A indicates that feathering is hardly conspicuous, B indicates that feathering is slightly conspicuous but has no practical problem, and C indicates that feathering is at a level lower than that.

[0080]

[Table 2]

As is clear from Table 2, in Examples 1 to 8, an image with high character quality can be formed and good image density can be obtained, whereas in Comparative Examples 1 to 8, feathering does not occur. It can be seen that there are conspicuous objects and the image density is low.

(Others) It should be noted that the present invention includes a means (for example, an electrothermal converter or a laser beam) for generating thermal energy as energy used for discharging ink, particularly in an ink jet recording system. An excellent effect is obtained in a recording head and a recording apparatus of a type in which the state of ink is changed by the thermal energy. This is because according to such a method, it is possible to achieve higher density and higher definition of recording.

The typical configuration and principle are described in, for example, US Pat. Nos. 4,723,129 and 4,740.
It is preferable to use the basic principle disclosed in the specification of Japanese Patent No. 796. This method is a so-called on-demand type,
Although it can be applied to any type of continuous type, in particular, in the case of the on-demand type, it can be applied to a sheet holding liquid (ink) or an electrothermal converter arranged corresponding to the liquid path. By applying at least one drive signal corresponding to the recorded information and providing a rapid temperature rise exceeding nucleate boiling, heat energy is generated in the electrothermal transducer, and film boiling occurs on the heat acting surface of the recording head. Liquid (ink) corresponding to this drive signal on a one-to-one basis.
This is effective because air bubbles inside can be formed. The liquid (ink) is ejected through the ejection opening by the growth and contraction of the bubble to form at least one droplet. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of a liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable. As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. Further, if the conditions described in US Pat. No. 4,313,124 relating to the temperature rise rate of the heat acting surface are adopted, more excellent recording can be performed.

As the configuration of the recording head, in addition to the combination of the discharge port, the liquid path, and the electrothermal converter (linear liquid flow path or right-angled liquid flow path) as disclosed in the above-mentioned specifications, U.S. Pat. No. 4,558,333 and U.S. Pat.
A configuration using the specification of Japanese Patent No. 59600 is also included in the present invention. In addition, Japanese Unexamined Patent Application Publication No. 59-123670 discloses a configuration in which a common slit is used as a discharge portion of an electrothermal converter for a plurality of electrothermal converters, and an aperture for absorbing a pressure wave of thermal energy is provided. The effect of the present invention is effective even if the configuration is based on JP-A-59-138461, which discloses a configuration corresponding to a discharge unit. That is, according to the present invention, recording can be reliably and efficiently performed regardless of the form of the recording head.

Further, the present invention can be effectively applied to a full-line type recording head having a length corresponding to the maximum width of a recording medium on which a recording apparatus can record. Such a recording head may have a configuration that satisfies the length by a combination of a plurality of recording heads, or a configuration as one integrally formed recording head.

In addition, even in the case of the serial type as described above, the recording head fixed to the apparatus main body or the electric connection with the apparatus main body and the ink from the apparatus main body when attached to the apparatus main body. The present invention is also effective when a replaceable chip-type recording head that can be supplied or a cartridge-type recording head in which an ink tank is provided integrally with the recording head itself is used.

Further, it is preferable to add ejection recovery means for the recording head, preliminary auxiliary means, and the like as the configuration of the recording apparatus of the present invention since the effects of the present invention can be further stabilized. If these are specifically mentioned, the recording head is heated using capping means, cleaning means, pressurizing or suction means, an electrothermal transducer, another heating element or a combination thereof. Pre-heating means for performing the pre-heating and pre-discharging means for performing the discharging other than the recording can be used.

The type and number of recording heads to be mounted are, for example, not only one provided for single color ink, but also a plurality of inks having different recording colors and densities. A plurality may be provided. That is, for example, the printing mode of the printing apparatus is not limited to a printing mode of only a mainstream color such as black, but may be any of integrally forming a printing head or a combination of a plurality of printing heads. The present invention is also very effective for an apparatus provided with at least one of the recording modes of full color by color mixture.

In addition, in the embodiments of the present invention described above, the ink is described as a liquid. However, an ink which solidifies at room temperature or lower and which softens or liquefies at room temperature may be used. In general, the ink jet method generally controls the temperature of the ink itself within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range. Sometimes, the ink may be in a liquid state. In addition, in order to positively prevent temperature rise due to thermal energy by using it as energy for changing the state of the ink from a solid state to a liquid state, or to prevent evaporation of the ink, the ink is solidified in a standing state and heated. May be used. In any case, the application of heat energy causes the ink to be liquefied by the application of the heat energy according to the recording signal and the liquid ink to be ejected, or to start solidifying when it reaches the recording medium. The present invention is also applicable to a case where an ink having a property of liquefying for the first time is used. In such a case, the ink
JP-A-54-56847 or JP-A-60-7
As described in Japanese Patent Publication No. 1260, it is also possible to adopt a form in which the sheet is opposed to the electrothermal converter in a state where it is held as a liquid or solid substance in the concave portion or through hole of the porous sheet. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

Further, the form of the ink jet recording apparatus of the present invention is not limited to the one used as an image output terminal of an information processing apparatus such as a computer, a copying apparatus combined with a reader or the like, and a facsimile apparatus having a transmission / reception function. It may take a form.

[0091]

As described above, according to the present invention,
An image with high character quality can be formed, and a good image density can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of an ink jet recording apparatus applied to the present invention.

FIG. 2 is a schematic perspective view of an ink jet head applied to the present invention.

FIG. 3 is an enlarged sectional view of an ink jet head applied to the present invention.

FIG. 4 is a schematic top view of an inkjet head unit applied to the present invention.

[Explanation of symbols]

20K, 20C, 20M, 20Y Ink tank 20S Processing liquid tank 30 Recording head 30K, 30C, 30M, 30Y, 30S Ink jet head 31 Heating element 32 Common liquid chamber 33 Substrate 34 Partition wall 35 Ink droplet 36 Protective film 37 Discharge port 100 Recording device 101 carriage 102 head case 103 recording head unit 104 guide shaft a 105 guide shaft b 106 recording medium 107 switch unit and display unit 108 platen 109 feed roller 110 recovery system unit 2201 processing liquid chip 2202 black (Bk) chip 2203 cyan (C) ) Chip 2204 Magenta (M) chip 2205 Yellow (Y) chip 2306 Frame

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Eriko Saito 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Shinya Shinya 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon (72) Inventor Yutaka Kurabayashi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (12)

[Claims] 1. An image forming method, comprising: applying an ink; and applying a liquid for insolubilizing or aggregating a coloring material in the ink, wherein the liquid is applied to a region where one pixel is formed. An image forming method, comprising: applying ink droplets of the same color in a plurality of times after the application. 2. An image forming method comprising the steps of: applying ink using a head that discharges ink; and applying the liquid using a head that discharges a liquid that insolubilizes or aggregates a coloring material in the ink. After applying the liquid to an area where one pixel is to be formed, ink droplets of the same color are applied in a plurality of times, and the ink drops applied in the same manner are ejected by the same ejection of the head. An image forming method, wherein the image is discharged from an outlet. 3. An image forming method comprising: applying ink using a head that discharges ink; and applying the liquid using a head that discharges a liquid that insolubilizes or aggregates a coloring material in the ink. In the method, after the liquid is applied to an area where one pixel is formed, ink droplets of the same color are applied in a plurality of times, and the ink drops applied in different ways are provided in different ejection ports of the head. An image forming method characterized in that the image is ejected from the image forming apparatus. 4. The ink droplet of the same color is applied two times, and the ejection amount Vd _{1 of the first} ink droplet and the two
The image forming method according to claim 1, the discharge amount Vd ₂ of ink drops originating th and satisfies the equation Vd ₁ ≦ Vd _2. 5. The method according to claim 1, wherein the number of application of the same color ink droplet is N.
(N> 2) times, and the ejection amount V of the first ink droplet
d _1, the discharge amount VDN of the ink droplet discharge amount Vd _2, and the N onset th ink droplets of the two shot first is to meet the Equation 1] _{Vd 1 + Vd 2 = Vd 1} + Vd 2 + ... VdN The image forming method according to claim 1, wherein: 6. The image forming method according to claim 1, wherein the ink contains an anionic colorant. 7. The image forming method according to claim 1, wherein the ink contains an anionic dye. 8. The image forming method according to claim 1, wherein the ink contains a pigment dispersed with an anionic substance. 9. The image forming method according to claim 5, wherein the liquid contains a cationic substance. 10. The image forming method according to claim 2, wherein the head has a thermal energy generator that generates thermal energy as energy sufficient to discharge the ink or the liquid. 11. The image forming method according to claim 10, wherein the thermal energy generator is an electrothermal converter. 12. An image forming apparatus for performing the image forming method according to claim 1, wherein a head for discharging ink and a liquid for insolubilizing or aggregating a coloring material in the ink are provided. An image forming apparatus to which a head for discharging can be mounted.