KR940009863B1 - Method for ink jet recording - Google Patents

Abstract

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Description

Inkjet recording method

1A and 1B are vertical longitudinal cross sectional and cross sectional views of the head of the ink-jet recording apparatus, respectively.

FIG. 2 is a perspective view of the appearance of a head composed of a plurality of sets of heads shown in FIGS. 1A and 1B;

3 is a perspective view of an example of an ink-jet recording apparatus,

4 is a longitudinal cross-sectional view of the ink cartridge,

5 is a perspective view of the recording unit.

* Explanation of symbols for main parts of the drawings

13: head 14: groove

15 heating head 16 protective layer

17-1, 17-2: electrode 18: heat resistant layer

19: heat storage layer 20: substrate

21: Ink 22: Orifice

23: meniscus 24: the droplet

[Background of invention]

[Field of Invention]

The present invention relates to an ink, an ink-jet recording method, and a mechanism for using the ink. More specifically, it is very detailed not only on coated paper specially prepared for ink-jet recording, but also on non-coated paper called matte white paper commonly used in offices and homes such as copy paper, recording paper, bond paper or continuous slip paper. The present invention relates to an ink, an ink-jet recording method, a recording unit, an ink-jet recording apparatus, and an ink cartridge, which can achieve high-quality recording, and are also suitable for a high-frequency driving ink-jet recording system using thermal energy.

[Background]

To date, inks which have been constructed in a wide variety of ways with respect to ink-jet recording inks have been reported. In particular, in recent years, detailed research and development has been carried out by accessing various research fields such as composition and physical properties so that excellent recording can be made on plain paper such as copy paper, recording paper, note paper or letter paper commonly used in offices. It is done.

In addition, with respect to ink-jet recording, a method in which electrically charged droplets are continuously generated so that a portion of the droplets is used for recording, a signal is given to a recording head equipped with a piezoelectric element, and droplets of the recording solution depend on the signal. Various methods have been proposed, including a method of generating and performing recording, and a method in which thermal energy according to a recording room is applied to a recording solution held in a chamber in a recording head, and droplets are generated by wearing the energy and recording is performed. come.

In particular, ink-jet recording of a type of ink ejecting ink utilizing an ink bubbling phenomenon generated by thermal energy, as disclosed in Japanese Patent Laid-Open No. 54-59936, facilitates higher densification and higher integration of the nozzle. This is a method that has recently attracted special attention. However, this method requires very strict conditions with respect to the ink to be used because other methods utilize boiling which is not used.

Preferred conditions for the ink used in this method can be listed as follows.

(1) Ink must be capable of producing excellent boiling in response to thermal energy so that droplets can be ejected stably from the small ejection orifice at all times without clogging.

(2) When recording is in a stopped state Even when the printer is left uncovered, the ink should be able to be ejected stably and immediately after recording is resumed. In other words, the ink should not dry easily adjacent to the ejection orifices so that clogging does not occur.

(3) High quality level images without irregular feathering should be able to form on blank paper.

(4) Printing can be quickly settled (or dried) on white paper so that it does not spread even in friction.

(5) The ink must have good storage stability and the performance of the ink must be able to be maintained for a long time.

(6) Inks should be excellent in stability, such as non-toxic and non-flammable.

In order to meet these demands, various methods of ink production have been proposed so far without any particular limitation on the thermal energy type related to the ejection method. For example, the ink usually contains a high-boiling organic solvent such as glycols for the purpose of drying prevention, clogging prevention and the like. When recording is performed using the inks on a highly sizing blank paper, the ink does not easily penetrate into the paper and the recorded portion is not dried well so that when the hand touches the written characters, etc. It may be contaminated or rubbed and look dim. So, there was a problem.

In such a situation, Japanese Patent Laid-Open No. 55-29546 proposes a method in which a large amount of surfactant is added to the ink in order to enhance ink permeability into paper. This caused the following problems: Feathering occurs very often on some types of paper; When the ink-jet recording head is filled, the ink may squeeze out of the orifice surface depending on the structure of the head so that no ink is ejected or all of the orifice surface is wet so that ink is not ejected.

Japanese Patent Laid-Open No. 56-57862 proposes a method of setting the ink pH toward the alkaline side. However, in this case, there is a disadvantage that the ink is harmful when contacted with the hand, or that the ink cannot be obtained in terms of feathering and drying performance when the ink is used on paper containing some kind of protective agent, such as neutralized paper. .

In addition to the above, various improvements have been made, but although there is no limit to the use of ink for thermal energy type recording, until now, ink that can solve all of the above problems and clogging problems for feathering, drying performance and ink stability is unknown. have. In addition, it is very important and difficult to design an ink that can respond well to boiling phenomena peculiar to thermal energy type recording under high frequency.

Overview of the Invention

Accordingly, it is an object of the present invention to achieve excellent boiling in response to thermal energy in high frequency driving, and to record on non-coated paper such as copy paper, report paper, note paper or letter paper commonly used in offices. It is to provide an ink which solves the problems of drying delay and feathering such as printed characters generated when executed, and to provide an ink-jet recording method and mechanism using the ink.

Another object of the present invention is to provide an ink-jet recording ink with high stability even when used in an office and at home.

It is still another object of the present invention to provide an ink having no clogging in the nozzle of the ink-jet recording head and having excellent reliability, and to provide a mechanism for using the ink.

The above objects of the present invention can be achieved by the present invention described hereinafter. The present invention provides an ink comprising a recording reagent and a liquid medium capable of dissolving or dispersing the recording reagent, wherein the ink contains 0.1 to 10% by weight of a water-soluble dye, 75 to 95% by weight of water, and 1,2,6-hexane tree. 4 to 20% by weight of a mixture of ol and ethylene oxide addition polymers.

The present invention also provides an ink-jet recording method comprising ejecting ink droplets from an orifice in accordance with a recording signal for recording on a recording medium, wherein the above-described ink is used.

The present invention also provides a recording unit comprising an ink container portion which holds the ink using the ink described above and a head in which ink is ejected in the form of ink droplets.

The present invention also provides an ink cartridge comprising an ink container portion for holding ink, wherein the ink described above is used.

The present invention also provides an ink-jet recording apparatus comprising an ink container portion holding ink and a recording unit including a head in which ink is ejected in the form of ink droplets, wherein the ink described above is used.

The present invention also provides an ink-jet recording apparatus comprising a recording head from which ink droplets are ejected, an ink cartridge having an ink container portion for holding ink, and an ink supply for supplying ink from the ink cartridge to the recording head. The ink described above is used.

Detailed Description of the Preferred Embodiments

The inventors of the present invention use the ink boiling phenomena generated by thermal energy to eject the ink, and can prevent the feathering, drying performance, and ink penetration on the white paper, and cause clogging in the nozzle of the ink-jet recording head. Intensive studies have been made on ink compositions with excellent reliability suitable for high frequency drive recording systems that do not have a high frequency. As a result, the inventors have found that ink containing a liquid medium consisting of a combination of 75 to 95% by weight of water and a mixture of 4 to 20% by weight of a mixture of 1,2,6-hexanetriol and an adpolymer of 1,2,6-hexanetriol and ethylene oxide is used to prevent feathering and It has been found that the balance in permeability can be well balanced and particularly good anti-clogging properties can be achieved. Thus, the inventors have completed the present invention.

As known by the present inventors, ethylene oxide adpolymers and glycerol have been used as conventional reagents for preventing ink clogging, of which glycerol is particularly preferable because glycerol can be prevented even with relatively small additions and no feathering occurs on the paper surface. It has been used as an anti-clogging agent. However, glycerol has a poor wettability to the protective agent inherent in paper, and thus has a disadvantage of having very poor ink drying performance or permeability on some kinds of paper surfaces.

The addition polymer of ethylene oxide may have an anti-clogging effect, but has a significantly lower effect on the problem of feathering than glycerol, and slightly better than glycerol but does not have a sufficiently high level of permeability.

On the other hand, the ethylene oxide adpolymer and 1,2,6-hexanetriol mixture as used in the present invention can significantly improve the anti-clogging properties than those used alone, and in terms of feathering, the actual glycerol It can have a performance equivalent to. In addition, the permeability was improved to a level unattainable at all by the conventional clogging inhibitor.

Cooperative effects due to the mixing of these compounds are thought to require detailed interpretation of the structural theory of the solution formed through hydrogen bonding, but no clear reason for this is unknown. However, due to the very strong binding force between solvent molecules and the affinity for the protective agent added to the paper inherent in the inside and the surface, it may show good properties for feathering, and due to the mixing of various solvent molecules, It can be presumed that the surprising balance required for ink-jet inks can be given so that the permeability can also be improved.

Regarding that the reaction to boiling can be remarkably improved, when the materials used in the ink of the present invention are mixed at a predetermined ratio, the ink boiling by the thermal energy and the wettability of the ink with respect to the members constituting the inside of the nozzle It may be considered that the development makes it particularly suitable for a recording method of ejecting ink.

The ink component of the present invention is described next.

What is used in the present invention and which mainly characterizes the present invention is a mixture of 1,2,6-hexanetriol and addition polymers of ethylene oxide used as water soluble solvents.

These materials should be mixed in a weight ratio of 1:20 to 20: 1, preferably 1:10 to 10: 1, more preferably 1: 5 to 5: 1.

The addition polymer of ethylene oxide may include ethylene oxide having a degree of polymerization of 2 to 20, preferably 2 to 10. More preferably triethylene glycol.

The mixture as described above may be added to the ink in an amount of 4 to 20% by weight, preferably 6 to 18% by weight, more preferably 8 to 16% by weight, which amount is other liquid medium component used for bonding. And dyes.

The amount of the mixture of 4% by weight or less may prevent the clogging effect from occurring, and an amount of 20% by weight or more may lead to the prevention of feathering and deterioration of permeability.

The water-soluble dyes constituting the ink of the present invention may include direct dyes, acid dyes, food coloring, basic dyes, reactive dyes and water-soluble bat dyes.

For example, a yellow dye may contain C.I. Direct yellow 12, 24, 26, 44, 86, 98, 100, 142; C.I. Acidic yellow 11, 17, 23, 25, 29, 42, 49, 61, 71; And C.I. Reactive yellow 2, 3, 13, 15, 17, 18, 23, 24, 37, 42, 57, 58, 64, 75, 76, 77, 79, 81, 84, 85, 87, 88, 91, 92, 93, 95, 102, 111, 115, 116, 130, 131, 132, 133, 135, 136, 137, 139, 140, 142, 143, 144, 145, 146, 147, 148, 151, 162, 163 Included. In particular, C.I. Direct yellow 86 or 142 is preferred.

Cyan dyes, for example, include C.I. Direct blue 6, 22, 25, 71, 86, 90, 106, 199; C.I. Acidic blue 9, 22, 40, 59, 93, 102, 104, 113, 117, 120, 167, 229, 234, 254; And C.I. Reactive blue 2, 3, 5, 8, 10, 13, 14, 15, 18, 19, 21, 25, 27, 28, 38, 39, 40, 41, 49, 52, 63, 71, 72, 74, 75, 77, 78, 79, 89, 100, 101, 104, 105, 119, 122, 147, 158, 160, 162, 166, 169, 170, 171, 172, 173, 174, 176, 179, 184, 190, 191, 194, 195, 198, 204, 211, 216, 217. In particular, C.I direct blue 86 or 199 is preferred.

Magenta dyes are for example C.I.Direct Red 1, 4, 17, 28, 83; C.I. Acidic heads 1, 6, 8, 32, 35, 37, 51, 52, 80, 85, 87, 92, 94, 115, 180, 256, 317, 315; And C.I. Reactive red 3, 13, 16, 21, 22, 23, 24, 29, 31, 33, 35, 45, 49, 55, 63, 85, 106, 109, 111, 112, 113, 114, 118, 126, 128, 130, 131, 141, 151, 170, 171, 174, 176, 177, 183, 184, 186, 187, 188, 190, 193, 194, 195, 196, 200, 201, 202, 204, 206, 218, 221. Especially the dye of following General formula (III) is preferable.

(Ⅲ)

In the formula, R represents a halogen atom, a lower alkyl group, a lower alcoholic group, a lower acrylamino group, a nitro group or a halogen atom; X represents an acetyl group, a benzoyl group, a paratoluenesolfonyl group or a 4-chloro-6-hydroxy-1,3,5-triazin-2-yl group; M represents an alkali metal, ammonium group or organic amine group; L represents 0 to 2; m and n represent 0 or 1, respectively.

The example is described next.

Black dyes include, for example, C.I. Direct black 17, 19, 32, 51, 62, 71, 108, 146, 154, 168; C.I. Acidic black 2, 7, 24, 26, 31, 52, 63, 112, 118; C.I. Reactive black 1, 5, 8, 13, 14, 23, 31, 34, 39; And C.I. Includes Food Black 1,2. In particular, the dyes represented by the following general formulas (I) and (II) and C.I. Food coloring black 2 is preferred.

… [Ⅰ]

Formula, A is a lower alkylcarbonyl group, a lower alkoxyl group, SO ₃ M group, SO ₃ M group substituted by a phenyl azo group which may be substituted lungs group, or an SO ₃ M group represents a substituted naphthyl; B represents a naphthyl group substituted with a SO ₃ M group or a phenyl group substituted with a lower alkoxyl group; M represents an alkali metal or an aluminum group.

… [II]

Equation, C represents a phenyl group substituted with a phenyl azo group, or a lower alkyl group or a lower alkoxyl group or an alkyl-carbonyl group which may be substituted with a naphthyl group, SO ₃ M substituted by a group SO ₃ M; R ₁ represents a lower alkyl group, a lower alkoxyl group or a lower alkylcarbonylamino group; R ₂ represents a hydrogen atom or a phenyl group substituted with a SO ₃ M group, n represents 0 or 1; M represents an alkali metal or ammonium group.

Examples of general formula (Ⅰ) structural formula:

Examples of structural formulas in general formula (II).

The amount of all these water-soluble dyes contained depends on the type of liquid media component, the properties required for the ink, and the like. Usually the dye may be contained in an amount of about 0.1 to 10% by weight, preferably 0.5 to 8% by weight, more preferably 1 to 5% by weight.

Water, which is the main component of the ink of the present invention, may be included in the ink in an amount of 75 to 95% by weight, preferably 78 to 92% by weight, more preferably 80 to 90% by weight. The amount of water below 75% by weight causes the amount of the organic solvent to be excessively high, causing the paper to curl or seriously lower the print quality level on the white paper. The amount of water of 95% by weight or more may excessively lower the jetting stability from the nozzle hole.

Essential components of the ink of the present invention are as described above. In combination, monohydric alcohols can be used, which can further improve response and permeability to thermal energy while suppressing irregular feathering.

In particular, monohydric alcohols which can be used include aliphatic monohydric alcohols, preferably aliphatic monohydric alcohols having 2 to 5 carbon atoms.

The amount of alcohol added depends on their type, and may be in the range of 0.1 to 10% by weight, preferably 0.5 to 5% by weight. The alcohol content of 0.1 wt% or less has a low effect on the reaction to thermal energy and the permeability of the ink. On the other hand, a content of more than 10% by weight can cause irregular feathering on some kinds of paper, resulting in severe image quality deterioration.

Other conventional organic solvents used in conventionally known inks can be used as long as they can be used as long as they do not interfere. For example, such organic solvents include amides such as dimethylformamide and dimethylacetamide; Ketones or ketone alcohols such as acetone and diacetone alcohol; Ethers such as tetrahydrofuran and dioxane; Oxypropylene addition polymers such as dipropylene glycol, tripropylene glycol and polypropylene glycol; Alkylene glycols having 2 to 6 carbon atoms with alkylene groups such as ethylene glycol, propylene glycol, trimethylene glycol, butylene glycol and hexylene glycol; Thiodiglycol; Glycerol; Lower alkyl ethers of polyhydric alcohols such as ethylene glycol monomethyl or ethyl ether, diethylene glycol monomethyl or ethyl ether and triethylene glycol monomethyl or ethyl ether; Lower dialkyl ethers of polyhydric alcohols such as triethylene glycol dimethyl or ethyl ether and tetraethylene glycol dimethyl or ethyl ether; Sulfolane, N-methyl-2-pyrrolidone, and 1,3-dimethyl-2-imidazolidinone.

The water-soluble organic solvent may be contained in an amount in the range of 1 to 15% by weight, preferably 1 to 10% by weight, based on the total weight of the ink.

Various other dispersants, surfactants, viscosity modifiers, surface tension modifiers, optical brighteners and the like may be optionally added.

For example, viscosity modifiers, such as polyvinyl alcohol, cellulose, and water-soluble resin; Surfactants of all kinds of cationic, anionic or nonionic type; Surface tension modifiers such as diethanolamine and triethanolamine; PH adjusters including buffers; And preservatives.

The ink of the present invention can solve problems related to drying performance and penetrability of feathering, recording characters, etc., which occur when recording is performed on a blank sheet or the like. At the same time, the ink can go well with the recording head in the improved state. From these viewpoints, the physical properties of the ink should be controlled to impart a surface tension of 30 dyne / cm 2 to 68 dyne / cm 2 and a viscosity of 10 cP or less, preferably 5 cP or less, more preferably 3 cP or less at 25 ° C.

Although the constitution and physical properties of the ink of the present invention have been described above, as a more preferable method of use, the ink is preferably used in a method generally followed by thermal energy type recording, particularly as disclosed in Japanese Patent Laid-Open No. 54-59936. The driving frequency may be 3.5KHz or more, preferably in the range of 4KHz to 20KHz, more preferably in the range of 4.5KHz to 10KHz. The boiling reaction of the ink of the present invention may be more apparent when the present ink is used for printing in which the ink is performed at a driving frequency of 3.5 KHz or higher.

The ink of the present invention can be particularly preferably used for ink-jet recording in which recording is performed by ejecting ink droplets by thermal energy action. Of course, it can also be used in conventional writing instruments.

A method and apparatus suitable for performing recording using the ink of the present invention include a method and apparatus in which thermal energy corresponding to the recording signal is applied to the ink retained inside the recording head so that ink droplets are generated by thermal energy action. Can be.

1a and 1b show structural examples of a head which is the main component of the device.

The head 13 is formed by joining a glass, ceramic or plastic plate having a groove 14 through which ink passes to the heating head 15 used for thermal recording. (The figure shows a kind of head, but is not limited to this. ). The heating head 15 includes a protective layer 16 formed of silicon oxide, a heat resistant layer 18 formed of aluminum electrodes 17-1, 17-2, a nichrome lamp, a heat storage layer 19, and an excellent heat shield. It is composed of a substrate 20 having acidity.

The ink 21 reaches the ejection orifice 22 (small opening) and the meniscus 23 is formed by the pressure P.

When an electrical signal is applied to the electrodes 17-1 and 17-2, heat is suddenly generated at the portion indicated by n of the heating head 15, and boiling bubbles are generated in the ink 21 in contact with the portion. . The pressure thus generated pushes the meniscus 23 so that the ink 21 is ejected from the orifice 22 in the form of recording droplets 24 and blows toward the recording medium 25. FIG. 2 illustrates a composite-head consisting of placing a plurality of heads as shown in FIG. 1A. The compound-head is made by bringing a glass plate 27 with compound-grooves 26 into close contact with a heating head 28 similar to the head as illustrated in FIG. 1A.

FIG. 1A is a cross sectional view of the head 13 along the ink flow path and FIG. 1B is a cross sectional view along the line A-B in FIG. 1A.

3 shows an example of an ink jet recording apparatus provided with such a head.

In Fig. 3, the member number 61 denotes a blade serving as a wiper member having a stop end at which one end is held by the blade holding member. The blade 61 is provided at a position adjacent to the area where the recording head writes. In this example, the blade is present in the form of a projection on the path through which the recording head moves. The reference numeral 62 denotes a cap provided in the original position adjacent to the blade 61, and is configured to be in contact with the surface of the jet port so as to move and cover in a direction perpendicular to the direction in which the recording head is moved. The reference numeral 63 denotes an ink absorbing member provided adjacent to the blade 61 and similarly to the blade 61, and is maintained in the form of protruding in the path in which the recording head is moved. The blade 61, the cap 62, and the ink absorbing member 63 constitute a jet-recovery portion 64, wherein the blade 61 and the ink absorbing member 63 have water and dust from the ink jet surface. Remove your back.

Reference numeral 65 denotes a recording head having ejection energy generating means, which ejects ink onto a recording medium set opposite to a ejection opening face provided with a ejection opening for performing recording. Reference numeral 66 denotes a carriage on which the recording head is mounted so that the recording head 65 can be moved. The carriage 66 is slidably connected to the guide rod 67. A portion of the carriage 66 is connected with a belt 69 driven by a motor 68 (not shown). Thus, the carriage 66 can be moved along the guide rod 67, and thus the recording head. 65 can be moved from the recording area to the area adjacent to it.

Reference numeral 51 denotes a paper feeder into which the recording medium is inserted, and 52 denotes a paper feed roller driven by a motor (not shown). With this configuration, the recording medium is supplied to a position opposed to the ejection opening face of the recording head, and in the recording home, the paper ejection roller 53 is ejected from the provided paper ejection portion.

In this configuration, the cap 62 of the ejection-recovery portion 64 withdraws from the path of movement of the recording head 65 when the recording head 65 has returned to its original position, for example after completion of the recording. , Blade 61 stands out on the path of movement. As a result, the ejection orifice surface of the recording head is washed. When the cap 62 is in contact with the spout surface of the recording head 65 to cover, the cap 62 is moved in such a way as to protrude into the movement path of the recording head. When the recording head 65 is moved from its original position to the position where recording starts, the cap 62 and the blade 61 are in the same position as the position where the jet port surface is wiped. As a result, the ejection orifice surface of the recording head 65 is also washed during this movement. The movement of the recording head to its original position is made not only upon completion of recording, ie, recovery of ejection, but also when moving between recording regions for recording while the recording head moves to the original position adjacent to each recording region at a given interval, Here, the ejection spherical surface is wiped in accordance with this movement. 4 shows an example of an ink cartridge indicated as 45 to which ink is supplied to the recording head through the ink supply member, as illustrated by the tube (not shown). Reference numeral 40 here denotes an ink container portion holding a supply ink as exemplified by an ink bag. Its upper part is provided with a stopper 42 made of rubber. A needle (not shown) may be fitted to this stoppo 42 to allow ink in the ink container portion to be supplied to the head. The member number 44 denotes an absorbent member that receives the dreg ink.

In the present invention, it is preferable that the ink holder is formed of polyolefin, in particular polyethylene, on the surface to which the ink comes into contact.

The ink jet recording apparatus used in the present invention is not limited to the apparatus as described above in which the head and the ink cartridge are provided separately, and the apparatus is also used integrally formed as shown in FIG. It may be desirable to be.

In Fig. 5, the member number 70 denotes a recording apparatus including an ink container portion containing ink as exemplified by the ink absorbing member. The recording apparatus is configured so that the ink in such an ink absorbing member ejects in the form of ink droplets from the head 71 having a plurality of holes. As the material for the ink absorbing member, it is preferable in the present invention to use polyurethane.

The member number 72 denotes an air passageway made to allow the inside of the recording apparatus to communicate with the atmosphere. This recording apparatus 70 can be used in place of the recording head shown in FIG. 3 and is detachably mounted to the cartridge 66.

The invention will be explained below in a more detailed manner by presenting examples and comparative examples. In the following, "part" and "%" represent weight unless otherwise indicated.

[Examples 1 to 6]

Each component was mixed and stirred for 5 hours as shown below. Thereafter, the resulting solution was adjusted to have a value of 7.5 pH with an aqueous 0.1% NaOH solution, and then pressure filtered using a membrane filter having a pore size of 0.22 μm.

As a result, the ink (A to F) of the present invention was obtained. Next, an ink jet printer (BJ-130) (trade name; manufactured by Canon Corp., Ltd.) using a resultant ink A to F and equipped with a heater as an energy source for ejecting ink as an ink jet recording apparatus. Was produced using a driving frequency of 4.5 KHz. Commercially available copy papers and bonds to evaluate the fixing performance of recorded characters, occurrence of feathering, prevention of reprinting after a temporary stop of printing, prevention of blockage when reprinting after long pauses, and frequency response The records were recorded. The obtained results are shown in Table 1. Tests for evaluation were always performed under conditions of 25 ° C. and 60% RH.

Ink A:

C.I. Food coloring black 2 part 3

1,2,6-hexanetriol 4 parts

Diethylene glycol 10 parts

83 parts of water

Ink B:

C.I. Food coloring black 2 part 1

1 part dye of Structural Formula BK-4

1 part dye of Structural Formula BK-6

1,2,6-hexanetriol 6 parts

Triethylene glycol 6 parts

1.5 parts of n-butanol

83.5 parts of water

Ink C:

Part 2 of the dye of structural formula BK-2

1,2,6-hexanetriol5 parts

Tetraethylene glycol 5 parts

Isopropanol 3 parts

85 parts water

Ink D:

C.I. Direct Yellow 86 Part 2

1,2,6-hexanetriol 6 parts

Triethylene glycol 3 parts

Glycerol 3 parts

Ethanol part 4

82 parts water

Ink E:

C.I. Acid Red 35 Part 2

1,2,6-hexanetriol7part

Polyethylene glycol (average molecular weight: 300) 4 parts

1 part n-methyl-2-pyrrolidone

Triethylene glycol monomethyl ether part 1

Ethylene glycol 2 parts

83 parts of water

Ink F:

C.I. Food coloring black 2 part 3

1,2,6-hexanetriol 6 parts

Triethylene glycol 6 parts

1.5 parts of n-butanol

83.5 parts of water

[Comparative Examples 1 to 5]

Using the same components as shown below, the inks G to K of Comparative Examples 1 to 5 were obtained in the same manner as in Examples 1 to 6, and all items were evaluated in the same manner as in Examples. Performed. The results obtained are shown in Table 1.

Ink G:

C.I. Food coloring black 2 part 3

12 parts of 1,2,6-hexanetriol

1.5 parts of n-butanol

83.5 parts of water

Ink H:

C.I. Food coloring black 2 part 3

Triethylene glycol 12 parts

1.5 parts of n-butanol

Water 83.5

Ink I:

C.I. Food coloring black part 2

1,2,6-hexanetriol1 part

Triethylene glycol 1 part

Water 96

Ink J:

C.I. Food coloring black 2 part 3

1,2,6-hexanetriol11parts

Triethylene glycol 12 parts

Water 74

Ink K:

C.I. Direct Black 2 Part 2

PEG 300 (polyethylene glycol, molecular weight 300) 14 parts

0.5 parts of nonionic surface active agent (brand surface: Nissan Nonion P-223: manufactured by Nippon Oil & Pad Co., Ltd.)

Water 83.5

TABLE 1

Table 1 (continued)

* 1) Settlement performance evaluation:

The characters were printed on commercially available copy paper and bond paper and the printed characters were rubbed with filter paper (trade name: No. 5C: manufactured by Toyoro-shi Kabuki Kaisha) after 20 and 30 seconds.

AA: No stains when rubbed after 10 seconds.

A: Fine stains when rubbed after 10 seconds.

B: Fine stains when rubbed after 30 seconds.

C: Smudges badly when rubbed after 30 seconds.

* 2) Feathering occurs

To test the occurrence of feathering, 300 dots were printed in a discontinuous form with a printer on commercial copy paper and bond paper. Thus, after leaving the printed dots for 1 hour or more, the number of dots in which feathering occurred was counted through microscopic observation. The ratio of the counted number to the total number of dots is expressed in%.

A: 10% or less

B: 11% to 30%

C: 31% or more

* 3) Prevent clogging when reprinting after pause:

In order to evaluate the prevention of clogging when printing was resumed after a temporary stop of printing, a given ink was charged to the printer, and printing was stopped after continuously printing English characters for 10 minutes. After maintaining the printing stop state for 10 minutes while the printer was not overwritten, the English characters were printed again. Evaluation was made on whether there were defective prints, such as letters with unclear edges or smeared letters.

A: No print defects seen in the first and subsequent characters

B: Some of the first letters are smeared or have unclear edges

C: The first character cannot be printed at all.

* 4) Prevent clogging when reprinting after a long stop

To evaluate the blockage observed when printing was restarted after a long pause in printing, a given ink was filled in the printer, and the printing was stopped after continuing to print English characters for 10 minutes. After the printing was stopped for seven days without the printer being covered, an operation for recovering the clogged nozzle was performed. The evaluation was based on the number of operations required for recovery and was performed until normal printing was possible without defect printing such as smeared letters or letters with unclear edges.

(Air condition: 60 ℃, 10 ± 5% RH)

A: Normal printing is possible after performing the recovery operation 1 to 5 times.

B: Normal printing is possible after performing the recovery operation 6 to 10 times.

C: Normal printing is possible after 11 or more recovery operations.

* 5) evaluation of frequency response

The state of printing obtained by printing, that is, defects such as smeared letters or blank areas, and defective ink droplet collisions such as spots or slips, etc., were observed by visual observation.

AA: Ink can be fired at a well-matched frequency, so that smudged text, blank areas, and defective ink droplet collisions do not appear in both solid and text prints.

A: Ink can be fired at a practically well-matched frequency, so that smudged characters, blank areas, and defective ink droplet collisions do not appear in text printing, but appear finely smeared in non-leading prints.

B: Character prints do not show speckles and blank areas, but defective ink droplets are partially visible, in non-leading prints, about 1/3 of the total print of non-leading prints.

C: A large number of blots and blank areas are seen in non-leading prints, and a large number of blots and defect print conflicts are also seen in character prints.

Example 7

C.I. used in ink (D). Direct Yellow 86 is represented by the structural formulas M-1, C.I. Inks (L, M, and N) were prepared in the same manner as in Example (D), except that the dye of Direct Blue 199 and the dye of Structural Formula BK-4 were respectively substituted. Color ink jet printer (PLXEL-PRO) loaded with four-color ink using ink (L, M and N), and an ink jet recording apparatus equipped with a heater element as an energy source for ink jet. Kaisha). Commercially available copy paper and bond paper for evaluating the settling performance of recording characters, occurrence of feathering, prevention of clogging when restarting after printing pause, prevention of clogging when restarting after a long pause in printing, and frequency response And ink-jet recording species (with ink-containing layer) were printed. As a result, it was possible to carry out the same recording as in Examples 1 to 6 without any difficulty.

As described above, according to the ink of the present invention, it is commonly used in offices such as copy paper, report paper, notebook, or stationery to obtain excellent boiling in response to thermal energy by high frequency driving printing, and to have excellent grade level and excellent permeability. It is possible to perform recording on the blank paper without causing feathering. In addition, according to the present invention, it is possible to obtain an ink having high stability even when used in offices and homes.

According to the present invention, it is also possible to perform recording with high reliability without causing clogging at the nozzle of the ink jet recording head. The use of the ink according to the present invention makes it possible to provide a device having high reliability.

Claims (1)

Thermal energy was applied to an ink containing 0.1 to 10% by weight of a water-soluble dye, 75 to 95% by weight of water, and 4 to 20% by weight of a mixture of 1,2,6-hexane triol and ethylene oxide adpolymer, according to a recording signal. An ink jet recording method characterized by ejecting a droplet of the ink from an orifice and recording on an uncoated recording sheet.