JP4208471B2 - Aqueous fluorescent ink, recording unit, ink cartridge, ink jet recording apparatus and ink jet recording method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a water-based fluorescent ink for ink-jet recording that performs recording by flying ink with thermal energy, an ink cartridge, a recording unit, an ink-jet recording apparatus, and an ink-jet recording method using the ink.
[0002]
[Prior art]
Conventionally, a fluorescent color material is used for a line marker pen or the like. More recently, inks using fluorescent pigments have been introduced to improve fastness. For example, JP-A-6-346013 and JP-A-5-239395 disclose fluorescent pigment inks for writing instruments using organic fluorescent pigments.
[0003]
In addition to the use as a writing instrument as described above, the fluorescent ink is also used for printing an electronic watermark or indicia of a postage by postage.
[0004]
Japanese Unexamined Patent Publication No. 9-291246 discloses the use of an ink jet printer for these prints. In this publication, in a water-resistant ink composition using a soluble toner, H.P. L. B. (Hydrophyl Lipophil Balance) discloses 8-15 nonionic surfactants as solubilizers.
[0005]
In the printing of digital watermarks and postal indicia, when using the fluorescence intensity of these printed matter as a threshold value, it is important to emit stable fluorescence. However, depending on the above prior art, stable fluorescence intensity may not be obtained.
[0006]
Furthermore, in ink jet recording (referred to as bubble jet) in which recording is performed by flying ink with thermal energy, in order to perform stable ink ejection, foam must be stabilized for ink ejection. The above ink was still not sufficient.
[0007]
[Problems to be solved by the invention]
An object of the present invention is to provide a water-based fluorescent ink that generates stable fluorescence and has excellent ink discharge properties when used in ink jet recording, particularly bubble jet recording, and has high ink discharge properties. It is an object of the present invention to provide a recording unit, an ink cartridge, an ink jet recording apparatus, and an ink jet recording method capable of stably obtaining a high quality image and obtaining a fluorescent image excellent in image fastness.
[0008]
[Means for Solving the Problems]
The above object is achieved by the present invention described below.
[0009]
  That is, the present inventionwater and,A resin emulsion colored with a fluorescent dye and a solid at 25 ° C.An aqueous fluorescent ink for ink jet containing a nonionic surfactant and polyethylene glycol,The nonionic surfactant and polyethylene glycol each have 25 or more ethylene oxide units, and the content of the nonionic surfactant and polyethylene glycol is from 1% by mass to 15% by mass with respect to the total mass of the ink. There is a water-based fluorescent ink for ink-jets.
[0010]
  In this ink,The content of the colored resin emulsion is 1% by mass or more and 40% by mass or less based on the total mass of the ink.It is preferable that
[0011]
  The resin emulsion is an acrylic resin emulsion.It is also preferable.
[0012]
It is also preferable that the water-soluble compound having the ethylene oxide unit is polyethylene glycol.
[0013]
It is also preferable that the polyethylene glycol has 25 or more ethylene oxide units.
[0014]
It is also preferable to contain 1 to 10% by mass of the polyethylene glycol with respect to the total mass of the ink.
[0015]
It is also preferable that the water-soluble compound having the ethylene oxide unit is a nonionic surfactant.
[0016]
It is also preferred that the nonionic surfactant has 25 or more ethylene oxide units.
[0017]
It is also preferable that the nonionic surfactant is contained in an amount of 1 to 5% by mass based on the total mass of the ink.
[0018]
It is also preferred that the compound having an ethylene oxide unit is polyethylene glycol and a nonionic surfactant.
[0019]
The present invention includes a recording unit including an ink storage unit that stores the above-described water-based fluorescent ink, and an ink jet head that discharges the ink.
[0020]
The present invention also includes an ink cartridge containing the above-described aqueous fluorescent ink.
[0021]
The present invention further includes an ink jet recording apparatus comprising an ink containing portion containing the above ink and an ink jet head for discharging the ink.
[0022]
In this ink jet recording apparatus, the ink jet head is preferably a bubble jet head.
[0023]
The present invention also includes an ink jet recording method including a step of discharging the above-described aqueous fluorescent ink by an ink jet method.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Next, the present invention will be described in more detail with reference to preferred embodiments.
[0025]
[Colored resin emulsion]
The emulsion of a resin colored with a fluorescent dye used in the present invention is a component as a coloring material in the ink according to the present invention. For example, an emulsion of an acrylic resin polymer compound dyed with a fluorescent dye ( (Hereinafter referred to as “acrylic polymer emulsion”).
[0026]
As the fluorescent dye, any dye having fluorescence can be used. I. Acid Blue 9, C.I. I. Acid Yellow 7, C.I. I. Acid Yellow 23, C.I. I. Acid Red 52, C.I. I. Acid Red 87, C.I. I. Acid Red 92, C.I. I. Acid dyes such as Acid Black 2, C.I. I. Basic Red 1, C.I. I. Basic Yellow 9, C.I. I. Basic Yellow 44, C.I. I. Basic Violet 1, C.I. I. Basic Violet 7, C.I. I. Basic Violet 10, C.I. I. Basic Violet 11, C.I. I. Basic dyes such as basic blue 45 can be mentioned, but not limited thereto.
[0027]
As monomers constituting the acrylic resin polymer emulsion, in addition to acrylic acid and methacrylic acid, styrene and vinyl chloride, esters of acrylic acid and methacrylic acid, maleic acid, fumaric acid and esters thereof, vinyl monomers such as acrylonitrile, In addition, urethane-based monomers can be used, but of course not limited thereto.
[0028]
In the method for producing an acrylic resin polymer emulsion, one or two or more of the above monomers are polymerized or copolymerized in a solvent such as water. The method of polymerization or copolymerization is not particularly limited, but is preferably synthesized by emulsion polymerization.
[0029]
The method of dyeing an acrylic resin polymer emulsion with a dye can be applied without particular limitation as long as it can dye a polymer compound. For example, a dye can be reacted with a monomer in the previous step of synthesizing the polymer compound. It can be obtained by reacting a dye during polymerization, or reacting or dyeing after synthesis.
[0030]
Since the content of the dye in the colored resin varies depending on the type of the dye and the like, it cannot be determined unconditionally, but the dye content in the colored resin is preferably 1% by mass or more and 10% by mass or less. If it is less than this, it may not be sufficient in terms of color development, and if the dye content is too high, water resistance may be insufficient, or fluorescence quenching may occur due to high dye concentration. .
[0031]
[Water-soluble compound having an ethylene oxide unit that is solid at 25 ° C.]
The ink of the present invention has, as an essential component, an ethylene oxide unit (—CH that is solid at 25 ° C.₂CH₂A water-soluble compound having O-).
[0032]
  This compoundAsSolid at 25 ° CIsPolyethylene glycolas well asNonionic surfactantIs used.
[0033]
  Even more specifically, polyethylene glycol having 25 or more ethylene oxide units.as well asNonionic surfactantIs used.
[0034]
In polyethylene glycol, the ethylene oxide unit is preferably 200 or less.
[0035]
In the nonionic surfactant, the ethylene oxide unit is preferably 60 or less.
[0036]
Examples of the nonionic surfactant as described above include polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene octyl. Specific examples include those having 25 or more ethylene oxide chains such as phenyl ether, polyoxyethylene stearylamine, and polyoxyethylene, but the present invention is not limited thereto.
[0037]
By the way, it is not clear why the water-soluble compound having an ethylene oxide unit, which is solid at 25 ° C., stabilizes the fluorescence of the ink jet recording by the ink according to the present invention. It is presumed that this is because it has the effect of suppressing the phenomenon in which the fluorescence intensity decreases due to the absorption of the light emission of the color material by another color material, but it is not certain.
[0038]
Furthermore, although it is not certain why these compounds improve the ink discharge performance in bubble jet recording, it is presumed as follows.
[0039]
Ink containing an emulsion of a resin colored with a fluorescent dye as described above is prevented from foaming for ink ejection due to the hydrophobic portion of the emulsion and does not grow into a sufficiently large bubble. It is thought to have been invited. In the following cases, an emulsion of a resin, that is, an emulsion in which a resin is dispersed is referred to as a “resin emulsion”, and an emulsion of a resin colored with a fluorescent dye is referred to as a “colored resin emulsion”.
[0040]
On the other hand, polyethylene glycol having about 20 ethylene oxide units that are liquid at 25 ° C. can be freely mixed with water. On the other hand, polyethylene glycol which is solid at 25 ° C. has a finite solubility and is considered to have lost its affinity for water at least as compared with a liquid compound. Therefore, these solid compounds are oriented to a colored resin emulsion having a more hydrophobic surface, and increase the apparent hydrophilicity of the emulsion. As a result, the suppression of foaming growth by the colored resin emulsion can be suppressed, and it is considered that stable ink ejection is achieved.
[0041]
The above description is the same for the nonionic surfactant. In this case, since the surfactant having hydrophobic units is more effectively oriented into the fluorescent pigment emulsion, the number of units of ethylene oxide is smaller than that of polyethylene glycol, and the same effect can be achieved with a small amount.
[0042]
In the case of surfactants other than solids with a small amount of ethylene oxide units, the hydrophobicity of the compound becomes strong, so it cannot be dissolved to a concentration that exhibits sufficient effects, or the hydrophobicity of the colored resin emulsion is reduced The effect is not obtained because of the decrease in size.
[0043]
〔ink〕
The aqueous fluorescent ink for ink jet according to the present invention is a colored resin (resin colored with a fluorescent dye) by mixing the colored resin emulsion and the compound having an ethylene oxide unit that is solid at 25 ° C. In other words, the pigment can be produced as a solution dispersed in an aqueous liquid medium such as water.
[0044]
The content of these colored resin emulsions is determined by the dye concentration in the resin, but is preferably 1 to 40% by mass, more preferably 1 to 20% by mass in the ink.
[0045]
  The compound having an ethylene oxide unit that is solid at 25 ° C. is contained in the ink in an amount of 1% by mass to 15% by mass.TheBy setting the content to 1% by mass or more, the effect of the present invention can be clearly exhibited, and by setting the content to 15% by mass or less, an increase in the viscosity of the ink can be suppressed. Moreover, even if it exceeds 15 mass%, the effect of this invention does not increase so much.
[0046]
The ink preferably contains 1 to 10% by mass of polyethylene glycol or 1 to 5% by mass of nonionic surfactant. Even if each content exceeds 10 or 5% by mass, it is disadvantageous in that the effect is not so much improved, and the increase in viscosity is somewhat disadvantageous for nozzle clogging of the inkjet head.
[0047]
It is also preferable to use these compounds in combination.
[0048]
The aqueous liquid medium that can be suitably used in the ink according to the present invention is a mixed solvent of water and a water-soluble organic solvent, and the water is not general water containing various ions but ion-exchanged water (deionized water). Is preferably used.
[0049]
Examples of the water-soluble organic solvent used by mixing with water include carbon atoms of 1 such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, and the like. Alkyl alcohols of -4; amides such as dimethylformamide and dimethylacetamide; ketones or ketoalcohols such as acetone and diacetone alcohol; ethers such as tetrahydrofuran and dioxane; polyalkylene glycols such as polyethylene glycol and polypropylene glycol; Ethylene glycol, propylene glycol, butylene glycol, triethylene glycol, 1,2,6-hexanetriol, thiodiglycol, hexylene glycol, diethylene glycol Alkylene glycols having 2 to 6 carbon atoms, such as coal; glycerin; ethylene glycol monomethyl (or ethyl) ether, diethylene glycol methyl (or ethyl) ether, triethylene glycol monomethyl (or ethyl) ether, etc. Lower alkyl ethers of monohydric alcohols; N-methyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone and the like. Of these many water-soluble organic solvents, polyhydric alcohols such as diethylene glycol and lower alkyl ethers of polyhydric alcohols such as triethylene glycol monomethyl (or ethyl) ether are preferred.
[0050]
The content of the water-soluble organic solvent in the ink as described above is generally preferably in the range of 3 to 50% by mass, more preferably in the range of 3 to 30% by mass with respect to the total mass of the ink.
[0051]
[Recording device]
Next, an example of the ink jet recording apparatus of the present invention suitable for recording using the above-described aqueous fluorescent ink of the present invention will be described below. The ink jet recording apparatus of the present invention is an ink container containing ink. Or a recording unit having a head unit for ejecting the ink as ink droplets by the action of thermal energy, wherein the ink is the aqueous fluorescent pigment ink of the present invention. There is no special limitation by this invention except being.
[0052]
First, an example of the head configuration is shown in FIGS. FIG. 1 is a cross-sectional view of the head 13 along the ink flow path, and FIG. 2 is a cross-sectional view taken along line AB in FIG. The head 13 is obtained by bonding a heating element substrate 15 to a glass, ceramic, silicon or plastic plate having a flow path (nozzle) 14 through which ink passes. The heating element substrate 15 includes a protective layer 16 formed of silicon oxide, silicon nitride, silicon carbide, etc., electrodes 17-1 and 17-2 formed of aluminum, gold, aluminum-copper alloy, HfB2, TaN, TaAl, etc. A heating resistor layer 18 formed of a high melting point material, a heat storage layer 19 formed of thermal silicon oxide, aluminum oxide, or the like, and a substrate 20 formed of a material with good heat dissipation such as silicon, aluminum, aluminum nitride. ing.
[0053]
When a pulsed electric signal is applied to the electrodes 17-1 and 17-2 of the head 13, the region indicated by n of the heating element substrate 15 rapidly generates heat, and bubbles are generated in the ink 21 in contact with the surface. The pressure causes the meniscus 23 to protrude, and the ink 21 is ejected through the nozzles 14 of the head to form ink droplets 24 from the ejection orifices 22 and fly toward the recording material 25. FIG. 3 shows an external view of an example of a multi-head in which a large number of heads shown in FIG. 1 are arranged. This multi-head is made by adhering a glass plate 27 having multi-nozzles 26 and a heating element substrate 28 similar to that described in FIG.
[0054]
FIG. 4 shows an example of an ink jet recording apparatus incorporating this head. In FIG. 4, reference numeral 61 denotes a blade as a wiping member, one end of which is held and fixed by a blade holding member, and forms a cantilever. The blade 61 is disposed at a position adjacent to the recording area by the recording head 65, and in this example, is held in a form protruding in the moving path of the recording head 65.
[0055]
Reference numeral 62 denotes a cap on the projection 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, contacts the ink ejection port surface, and performs capping. The structure to perform is provided. Further, reference numeral 63 denotes an ink absorber provided adjacent to the blade 61 and, like the blade 61, is held in a form protruding in the moving path of the recording head 65. The blade 61, the cap 62, and the ink absorber 63 constitute a discharge recovery portion 64, and the blade 61 and the ink absorber 63 remove moisture, dust, and the like from the discharge port surface.
[0056]
Reference numeral 65 denotes a recording head that has discharge energy generating means and performs recording by discharging ink onto a recording material facing the discharge roll surface provided with the discharge ports. It is a carriage for moving. The carriage 66 is slidably engaged with the guide shaft 67, and a part of the carriage 66 is connected to a belt 69 (not shown) driven by a motor 68.
[0057]
As a result, the carriage 66 can move along the guide shaft 67, and the recording area and its adjacent area can be moved by the recording head 65.
[0058]
51 is a paper feeding unit for inserting a recording material, and 52 is a paper feed roller driven by a motor (not shown). With these configurations, the recording material is fed to a position facing the discharge port surface of the recording head 65, and is discharged to a paper discharge portion provided with a paper discharge roller 53 as recording progresses. In the above configuration, when the recording head 65 finishes recording and returns to the home position, the cap 62 of the ejection recovery unit 64 is retracted from the moving path of the recording head 65, but the blade 61 protrudes into the moving path. As a result, the ejection port of the recording head 65 is wiped.
[0059]
When the cap 62 is in contact with the ejection surface of the recording head 65 to perform capping, 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 that at the time of wiping described above. As a result, the ejection port surface of the recording head 65 is also wibbed during this movement. The above-mentioned movement of the recording head to the home position is not only at the end of recording or at the time of ejection recovery, but also to the home position adjacent to the recording area at a predetermined interval while the recording head moves the recording area for recording. Then, the wiping is performed with this movement.
[0060]
FIG. 5 is a view showing an example of an ink cartridge (not shown in FIG. 4) in which the recording head in FIG. 4 accommodates ink supplied via an ink supply member, for example, a tube. 45 is an ink cartridge. Here, reference numeral 40 denotes an ink container, for example, an ink bag, in which supply ink is stored, and a rubber plug 42 is provided at the tip thereof. By inserting a needle (not shown) into the stopper 42, the ink in the ink bag 40 can be supplied to the head. An ink absorber 44 receives waste ink. The ink container preferably has a liquid contact surface made of polyolefin, particularly polyethylene.
[0061]
The ink cartridge of the present invention is not particularly limited as long as it has an ink storage portion that stores ink, except that the ink to be stored is the aqueous fluorescent pigment ink of the present invention.
[0062]
In the present invention, not only the head and the ink cartridge are separated as described above, but also a recording unit in which they are integrated as shown in FIG. 6 is preferably used. In FIG. 6, reference numeral 70 denotes a recording unit, in which an ink storage portion that stores ink, for example, an ink absorber is stored, and the ink in the ink absorber from the head portion 71 having a plurality of orifices. It is configured to be ejected as ink droplets. It is preferable for the present invention to use polyurethane as the material of the ink absorber. Alternatively, a structure may be used in which the ink container is an ink bag with a spring or the like inside without using an ink absorber. Reference numeral 72 denotes an atmosphere communication port for communicating the inside of the cartridge with the atmosphere. The recording unit 70 is used in place of the recording head 65 shown in FIG. 4 and is detachable from the carriage 66.
[0063]
As the recording unit of the present invention, as long as the recording unit includes an ink storage unit that stores ink and a head unit that discharges the ink as ink droplets by the action of thermal energy, the stored ink is the same as that of the present invention. There is no particular limitation except that it is an aqueous fluorescent pigment ink.
[0064]
【Example】
EXAMPLES Next, although an Example and a comparative example are given and this invention is demonstrated more concretely, this invention is not limited by the following Example. In the text, “parts” and “%” are based on mass unless otherwise specified.
[0065]
  [referenceExample 1)
1) Aqueous fluorescent colored resin emulsion
・ Acrylic resin emulsion colored with fluorescent acid dye
(Product name: SF-5017; manufactured by Sinloihi): 20 parts
2) Nonionic surfactant
Polyoxyethylene cetyl ether (ethylene oxide 40 units), 25 ° C. solid)
(Product name: BC-40TX; manufactured by Nikko Chemicals): 2.0 parts
3) Other ingredients
・ Ethylene oxide adduct of acetylene glycol
(Brand name: Acetylenol EH: Kawaken Fine Chemical Co., Ltd.): 0.5 parts
・ Diethylene glycol: 15 parts
・ Trimethylolpropane: 5 parts
・ Pure water: 57.5 parts
  The above components were mixed, sufficiently stirred and dissolved, and then pressure filtered with a microfilter (manufactured by Fuji Film) having a pore size of 2.5 μm to prepare an ink.
[0066]
Using the above-described ink, print evaluation is performed using an inkjet recording apparatus BJC-430J (manufactured by Canon) having an on-demand type multi-bubble jet head that discharges ink by applying thermal energy corresponding to a recording signal to the ink. went.
[0067]
The paper used for the evaluation is Canon PPC paper, PB-paper.
[0068]
As a result, a stable print could be obtained. Further, the printed matter had complete water resistance. When the printed matter was measured with a fluorometer, red fluorescence was observed, and no variation in fluorescence intensity due to paper lots was observed.
[0069]
  [referenceExample 2)
1) Aqueous fluorescent colored resin emulsion
・ Acrylic resin emulsion colored with fluorescent acid dye
(Product name: LUMIKOL NKW-3207C; manufactured by Nippon Fluorescence): 15 parts
2) Polyethylene glycol
Polyethylene glycol (molecular weight 4000, ethylene oxide average about 90 units, 25 ° C. solid): 7.0 parts
3) Other ingredients
・ Diethylene glycol: 15 parts
・ Trimethylolpropane: 5 parts
・ Ethylene oxide adduct of acetylene glycol
(Product name: Acetylenol EH; Kawaken Fine Chemical Co., Ltd.): 0.5 parts
・ Pure water: 57.5 parts
  Except for using the above ingredientsreferenceWhen print evaluation was performed in the same manner as in Example 1, good results were obtained. Also,referenceIn Example 2, red fluorescence is observed,referenceAs in Example 1, the fluorescence intensity was stable.
[0070]
  〔Example1]
1) Aqueous fluorescent colored resin emulsion
  Acrylic resin emulsion colored with fluorescent acid dye
(Product name: SF-5014; manufactured by Sinloihi): 30 parts
2) Polyethylene glycol and nonionic surfactant
・ Polyethylene glycol
(Molecular weight 1000, ethylene oxide average 25 units, 25 ° C. solid): 5.0 parts
・ Polyoxyethylene oleyl ether (ethylene oxide 50 units)
(Product name: B0-50; manufactured by Nikko Chemicals): 2.0 parts
3) Other ingredients
・ Diethylene glycol: 15 parts
・ Trimethylolpropane: 5 parts
・ Ethylene oxide adduct of acetylene glycol
(Product name: Acetylenol EH; Kawaken Fine Chemical Co., Ltd.): 0.5 parts
・ Pure water: 42.5 parts
  Except for using the above ingredients,referenceWhen print evaluation was performed in the same manner as in Example 1, good results were obtained. Yellow-green fluorescence is observed,referenceAs in Example 1, the fluorescence intensity was stable. Example1Therefore, the combined use of polyethylene glycol and surfactant enabled stable use even at high emulsion concentrations.
[0071]
  [Comparative Example 1]
1) Aqueous fluorescent resin emulsion
・ Acrylic resin emulsion colored with fluorescent acid dye
(Product name: SF-5017; manufactured by Sinloihi): 20 parts
2) Other ingredients
・ Diethylene glycol: 15 parts
・ Trimethylolpropane: 5 parts
・ Ethylene oxide adduct of acetylene glycol
(Product name: Acetylenol EH; Kawaken Fine Chemical Co., Ltd.): 0.5 parts
・ Pure water: 59.5 parts
  referenceWhen printing was evaluated in the same manner as in Example 1, no ink was ejected from the print head, and no evaluation was possible.
[0072]
  [Comparative Example 2]
1) Aqueous fluorescent colored resin emulsion
Resin emulsion colored with fluorescent acid dyes
(Product name: SF-5017; manufactured by Sinloihi): 20 parts
2) Nonionic surfactant
・ Polyoxyethylene cetyl ether (10 units of ethylene oxide), 25 ° C liquid to paste
(Product name: BC-10TX; manufactured by Nikko Chemicals): 2.0 parts
3) Other ingredients
・ Diethylene glycol: 15 parts
・ Trimethylolpropane: 5 parts
・ Ethylene oxide adduct of acetylene glycol
(Product name: Acetylenol EH; Kawaken Fine Chemical Co., Ltd.): 0.5 parts
・ Pure water: 57.5 parts
  referenceWhen print evaluation was performed in the same manner as in Example 1, the print was faint and evaluation was difficult.
[0073]
When the fluorescence intensity was measured by selecting a portion with good printing, it seemed that there was no problem with the printing density or the like by visual observation, but the fluorescence intensity varied and was not at a level that could be used for digital watermarking.
[0074]
  [Comparative Example 3]
1) Aqueous fluorescent colored resin emulsion
・ Acrylic resin emulsion colored with fluorescent acid dye
(Product name: SF-5014; manufactured by Sinloihi): 20 parts
2) Polyethylene glycol
Polyethylene glycol (molecular weight 200, liquid at 25 ° C.): 5.0 parts
3) Other ingredients
・ Diethylene glycol: 15 parts
・ Trimethylolpropane: 5 parts
・ Ethylene oxide adduct of acetylene glycol
(Product name: Acetylenol EH; Kawaken Fine Chemical Co., Ltd.): 0.5 parts
・ Pure water: 54.5 parts
  referenceWhen printing was evaluated in the same manner as in Example 1, ink could not be ejected from the print head, and evaluation was not possible.
[0075]
【The invention's effect】
As described above, according to the present invention, it is possible to obtain an aqueous fluorescent ink for ink jet excellent in ink discharge performance and image fastness when used in bubble jet recording. Furthermore, there are provided an ink cartridge, a recording unit, an ink jet recording apparatus and a method capable of stably obtaining a high-quality image due to excellent ink ejection properties and obtaining a fluorescent image excellent in image fastness. It was done.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing an example of a head of an ink jet recording apparatus.
FIG. 2 is a cross-sectional view illustrating an example of a head of an ink jet recording apparatus.
FIG. 3 is an external perspective view of a head in which the head shown in FIG.
FIG. 4 is a schematic perspective view illustrating an example of an ink jet recording apparatus.
FIG. 5 is a longitudinal sectional view showing an example of an ink cartridge.
FIG. 6 is a perspective view illustrating an example of a recording unit.
[Explanation of symbols]
13: Head
14: Nozzle
15: Heating element substrate
16: Protective layer
17-1, 17-2: Electrodes
18: Heating resistor layer
19: Thermal storage layer
20: Substrate
21: Ink
22: Discharge orifice (fine hole)
23: Meniscus
24: Ink droplet
25: Recording material
26: Multi nozzle
27: Glass plate
28: Heating element substrate
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: Discharge recovery part
65: Recording head
66: Carriage
67: Guide shaft
68: Motor
69: Belt
70: Recording unit
71: Head part
72: Air communication port

Claims (7)

water and,
An emulsion of resin colored with a fluorescent dye;
A nonionic surfactant and polyethylene glycol that are solid at 25 ° C . ;
An aqueous fluorescent ink for inkjet containing
The nonionic surfactant and polyethylene glycol each have 25 or more ethylene oxide units,
An aqueous fluorescent ink for ink- jets, wherein the content of the nonionic surfactant and polyethylene glycol is from 1% by mass to 15% by mass with respect to the total mass of the ink. The aqueous fluorescent ink for inkjet according to claim 1, wherein the content of the resin emulsion is 1% by mass or more and 40% by mass or less based on the total mass of the ink. 3. The aqueous fluorescent ink for ink jet according to claim 1, wherein the resin emulsion is an acrylic resin emulsion. An ink storage unit storing the aqueous fluorescent ink according to any one of claims 1 to 3 and a head unit for discharging the ink as ink droplets by the action of thermal energy . A recording unit characterized by that. An ink cartridge containing the water-based fluorescent ink according to any one of claims 1 to 3 . An ink storage unit storing the aqueous fluorescent ink according to any one of claims 1 to 3 and a head unit for discharging the ink as ink droplets by the action of thermal energy . An ink jet recording apparatus. An ink jet recording method in which the aqueous fluorescent ink according to any one of claims 1 to 3 is ejected as ink droplets by the action of thermal energy .

Images