JP2002012803A - Ink for ink jet, method for reducing scorched deposit to heater, method for ink jet recording, apparatus for ink jet recording, method for making recording head have long life and recording unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an ink capable of reducing scorched deposits to a heater surface for discharging the ink to a recording head by applying a thermal energy to the ink, provide a method for reducing scorched deposits of a recording head to a heater, a method for ink jet recording capable of presenting a high quality printing and attaining to make the head have a long life, a recording apparatus and a method for making the recording head have the long life. SOLUTION: This ink for ink jet contains a colorant, a liquid medium and one or more species of ammonium salts of an acid having a methyl group or a methylene group and a carboxy group, or contains a colorant, a liquid medium and an ammonium aldonate, or contains a colorant, a liquid medium and one or more of compounds selected from monoammonium dihydrogen citrate, diammonium hydrogen citrate, triammonium citrate. A method for reducing scorched deposits, a recording method, an apparatus and the like and a method for making the head have a long life are also claimed in this invention.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet ink, a method for reducing kogation on a heater, an ink jet recording method, an ink jet recording apparatus, a method for extending the life of a recording head, and a recording unit.

[0002]

2. Description of the Related Art Conventionally, various methods have been devised for printing using an ink jet recording method. Among them, for example, an ink described in JP-A-54-51837 is used. In the ink jet method (so-called bubble jet method) in which ink droplets are ejected by the action of energy, a high-density multi-nozzle is very simple, so that a high-quality image can be obtained at high speed and at very low cost, and is special. It has the feature that it can be printed on plain paper that does not have a special coat layer or the like. In this method, when the heater of the recording head is rapidly heated, the liquid on the heater generates bubbles to cause a sudden increase in volume, and the acting force based on the sudden increase in the volume causes the tip of the recording head portion to move. The droplet is ejected from the nozzle, flies, adheres to the recording material, and printing is performed.

However, in this method, the heater of the recording head is repeatedly heated every time the ink is ejected. Therefore, when a large amount of printing is performed, a decomposition product (so-called kogation) of the ink may be deposited on the heater surface. . When kogation accumulates, the thermal energy is not effectively transmitted from the heater to the ink, and the amount of ejected droplets and the speed of ejected droplets decrease compared to the initial stage, which affects image quality. Occurs. In this case, it is necessary to replace the recording head in order to continuously obtain high quality printing, and such a situation leads to an increase in the total printing cost for the user.

[0004] Accordingly, to further reduce the sticking of kogation on the heater, which may cause such a situation, and to further extend the life of the recording head, it is necessary to use a bubble jet (registered trademark) recording method. Has always been one of the important technical issues when aiming for further improvement. For example, JP-A-3-160070 proposes an ink containing an oxo anion. And, as the oxo anion, phosphate, polyphosphate, phosphate, arsenate, molybdate, sulfate, sulfite, and oxalate are mentioned.

However, in such an ink, in the process of repeatedly discharging the ink, these phosphates,
Polyphosphates, phosphates, arsenates, molybdates, sulphates, sulphite and oxalates form from metals and / or metal oxides, such as tantalum, which are formed on the heating resistor and come into contact with the ink. In some cases, the outermost protective film may be melted and the heater may be disconnected, making it difficult to discharge ink.
In addition, the ability to prevent kogation is insufficient.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to apply thermal energy to ink in a printhead to prevent kogation on a heater surface for discharging the ink from the printhead. It is an object of the present invention to provide an ink-jet ink and a method of reducing kogation adherence to a heater of an ink-jet recording head which can be further reduced. Another object of the present invention is to provide an ink jet recording method and an ink jet recording apparatus capable of performing higher quality printing and achieving a longer life of the recording head. is there. It is another object of the present invention to provide a recording unit capable of performing high-quality printing for a longer period. Still another object of the present invention is to provide a method for extending the life of a recording head, which can achieve excellent quality printing at a lower cost.

[0007]

Means for Solving the Problems [First invention] According to the first invention of the present invention, (a) a coloring material, (b) a liquid medium, and (c) a methyl group or a methylene group and a carboxyl group An inkjet ink containing at least one ammonium salt of an acid having the formula: According to another embodiment of the first invention, a heater for applying thermal energy to the ink to eject the ink from the orifice and a top surface protective layer containing a metal and / or a metal oxide for protecting the heater (A) a coloring material, (b) a liquid medium, and (c) an ammonium salt of an acid having a methyl group or a methylene group and a carboxyl group. Is provided.

According to another embodiment of the first invention, the heater surface in an ink jet recording apparatus provided with a recording head having a heater for applying thermal energy to the ink to discharge the ink from the orifice. A method for reducing kogation adherence to metal, wherein the heater is made of metal and / or
Alternatively, there is provided a method for reducing kogation on a heater, comprising a top surface protective layer containing a metal oxide, and using the above-mentioned ink-jet ink as the ink.

According to another embodiment of the first invention, there is provided an ink-jet recording method using the above-described ink-jet ink in an ink-jet recording method including a step of applying thermal energy to an ink to discharge the ink from an orifice. . Further, according to another embodiment of the first invention, an ink jet recording apparatus having an ink storing section for storing ink, and a heater for applying thermal energy to ink in an ink flow path led from the ink storing section. What is claimed is: 1. An ink jet recording apparatus comprising: a head; and means for applying a pulsed electric signal to the heater in accordance with recording information, wherein the heater includes a top surface protection layer containing a metal and / or a metal oxide. In addition, there is provided an ink jet recording apparatus, wherein the ink is the ink for ink jet.

According to another embodiment of the first invention,
A method for extending the life of a recording head having a heater for applying thermal energy to ink, which is used in an inkjet recording method including a step of applying thermal energy to ink and discharging the ink from an orifice. /
Alternatively, there is provided a method for extending the life of a recording head in which an outermost surface protective layer containing a metal oxide is provided and the ink is any one of the inks for inkjet.

In the case where an image is formed on the ink jet recording apparatus having the above structure using the ink having the above structure,
It is possible to extremely effectively reduce the adhesion of kogation to the outermost protective layer of the heater for applying thermal energy to the ink to eject the ink from the orifice. It is not clear why such an effect is obtained by using the ink having the configuration according to the first invention of the present invention, but the ink is selected from ammonium salts of an acid having a methyl group or a methylene group and a carboxyl group in the ink. Compound interacts with the metal and / or metal oxide constituting the outermost protective layer of the heater to prevent the adhesion of kogation, or to promote the decomposition of kogation and peeling of kogation from the heater surface. it is conceivable that.

According to a detailed study by the present inventors, in particular, the metal and / or metal contained in the outermost protective layer of the heater are considered.
Alternatively, it has been found that when the metal oxide is tantalum or a tantalum oxide, the effect is more remarkable. Further, the amount of energy input to the heater for applying thermal energy to the ink to discharge the ink from the orifice is E _op , and the minimum amount of energy input to the heater for discharging the ink is E E when the _th, when a value of _{E op / E th (= γ} ) sets the energy input to the heater so as to satisfy the following relationship, it is possible and that even better kogation prevention effect, It was also found that the heater did not break, and that the discharge durability was excellent. 1.10 ≦ E _op / E _th ≦ 1.75

Further, according to another embodiment of the first invention, there is provided an ink storage section for storing ink, and an ink jet recording head section for discharging the ink from the orifice by the action of thermal energy. A recording unit, wherein the ink jet recording head includes a heater provided with a top surface protective layer containing a metal and / or a metal oxide for applying thermal energy to the heater, and the ink comprises the ink jet recording head. A recording unit that is an ink for use is provided.

[Second Invention] According to a second invention of the present invention, there is provided an ink jet ink containing (a) a coloring material, (b) a liquid medium, and (d) an ammonium aldonic acid salt. According to another embodiment of the second invention, at least the metal or / and metal oxide is provided on the outermost surface protective layer of the heater of the ink jet recording head for discharging the ink as ink droplets by the action of thermal energy. An ink-jet ink used for an ink-jet recording apparatus containing at least one of (a) a colorant, (b) a liquid medium, and (d) at least one of ammonium aldonic acid salts. An ink is provided.

According to another embodiment of the second invention, the heater surface in the ink jet recording apparatus provided with a recording head having a heater for applying thermal energy to the ink to discharge the ink from the orifice. A method for reducing kogation adherence to metal, wherein the heater is made of metal and / or
Or a recording head heater comprising a top surface protective layer containing a metal oxide, and using, as the ink, an inkjet ink containing (a) a coloring material, (b) a liquid medium, and (d) ammonium aldonic acid salt. A method is provided for reducing kogation deposited thereon. According to another embodiment of the second invention, a step of applying thermal energy to the inkjet ink containing (a) the colorant, (b) the liquid medium, and (d) the ammonium aldonic acid salt to eject the ink from the orifice. An inkjet recording method comprising:

According to another embodiment of the second aspect of the invention, there is provided an ink jet recording apparatus having an ink storing section for storing ink and a heater for applying thermal energy to the ink in the ink flow path led from the ink storing section. A recording head, and an inkjet recording apparatus comprising means for applying a pulse-like electric signal to the heater according to recording information,
The heater includes a top surface protective layer containing a metal and / or a metal oxide, and the ink comprises: (a) a coloring material;
An ink jet recording apparatus is provided which is an ink jet ink containing (b) a liquid medium and (d) an ammonium aldonic acid salt.

According to another embodiment of the second invention, there is provided a heater for applying thermal energy to the ink, which is used in an ink jet recording method including a step of applying thermal energy to the ink and discharging the ink from an orifice. A method for extending the life of a recording head, wherein the heater is provided with an outermost surface protective layer containing a metal and / or a metal oxide, and the ink contains (a) a color material, (b) a liquid medium, and (d) A) A method of extending the life of a recording head using an inkjet ink containing an ammonium aldonic acid salt is provided.

In particular, in the method for reducing kogation, the ink jet recording method, and the ink jet recording apparatus using the ink according to the second aspect of the present invention containing ammonium aldonic acid as the component (d), the heater of the ink jet recording apparatus is used. When the energy input to the heater for discharging ink is E _op and the minimum energy input to the heater for discharging ink from the recording head is E _th , these energy ratios E _op
When applied to an ink jet recording apparatus in which / E _th (= γ) is controlled to satisfy the following relationship, it is possible to more effectively reduce the deposition of kogation on the heater of the ink jet recording head. it can. 1.10 ≦ E _op / E _th ≦ 1.90

According to another embodiment of the second invention,
A recording unit having an ink containing section containing ink and an ink jet recording head section for discharging the ink from an orifice by the action of thermal energy, wherein the ink jet recording head applies heat energy to the heater. A heater provided with an outermost surface protective layer containing a metal and / or a metal oxide for applying, wherein the ink comprises (a) a colorant, (b) a liquid medium, and (d) an ammonium aldonic acid salt. The present invention provides a recording unit which is an ink-jet ink.

[Third Invention] According to the third invention of the present invention, (a) a coloring material, (b) a liquid medium, and (e) monoammonium citrate, diammonium citrate and citric acid There is provided an inkjet ink including at least one compound selected from triammonium.
According to another embodiment of the third invention, a heater for applying thermal energy to the ink to eject the ink from the orifice and an outermost surface containing metal and / or metal oxide for protecting the heater An ink used in an ink jet recording apparatus having a recording head provided with a protective layer, comprising: (a) a coloring material, (b) a liquid medium, and (e) monoammonium citrate, diammonium citrate and tricitrate. There is provided an inkjet ink containing at least one compound selected from ammonium.

According to another embodiment of the third invention,
A method of reducing kogation on a heater surface in an ink jet recording apparatus provided with a recording head having a heater for applying thermal energy to ink to eject the ink from an orifice, wherein the heater is made of metal and / or Or a top surface protective layer containing a metal oxide, and
(A) a coloring material, (b) a liquid medium, and (e)
Provided is a method for reducing kogation on a heater using an inkjet ink containing at least one compound selected from monoammonium citrate, diammonium citrate and triammonium citrate.

According to another embodiment of the third invention,
Applying thermal energy to an inkjet ink containing (a) a coloring material, (b) a liquid medium, and (e) at least one compound selected from monoammonium citrate, diammonium citrate, and triammonium citrate And an ink jet recording method including a step of discharging from an orifice.

According to another embodiment of the third invention,
It contains (a) a colorant, (b) a liquid medium, and (e) an inkjet ink containing at least one compound selected from monoammonium citrate, diammonium citrate and triammonium citrate. An ink storage unit, an ink jet recording head having a heater for applying thermal energy to ink in an ink flow path led from the ink storage unit, and a unit for applying a pulse-like electric signal to the heater according to recording information. An ink jet recording apparatus is provided.

According to another embodiment of the third invention,
Applying thermal energy to an inkjet ink containing (a) a coloring material, (b) a liquid medium, and (e) at least one compound selected from monoammonium citrate, diammonium citrate, and triammonium citrate A method for extending the life of a recording head having a heater for applying thermal energy to ink, which is used in an inkjet recording method including a step of discharging the ink from an orifice,
Provided is a method for extending the life of a recording head in which a heater is provided with an outermost surface protective layer containing a metal and / or a metal oxide.

When an image is formed on the ink jet recording apparatus having the above-described structure using the ink according to the third aspect of the present invention, a heater for applying thermal energy to the ink to discharge the ink from the orifice. It is possible to extremely effectively reduce the adhesion of kogation to the outermost surface protective layer. It is not clear why such an effect can be obtained by using the ink of the third invention, but a compound selected from monoammonium citrate, diammonium citrate and triammonium citrate in the ink,
Interacts with the metal and / or metal oxide constituting the outermost protective layer of the heater to prevent kogation, or
It is considered that the decomposition of the kogation and the peeling of the kogation from the heater surface are promoted.

According to a detailed study by the present inventors, in particular, metals contained in the outermost protective layer of the heater and / or
Alternatively, it has been found that when the metal oxide is tantalum or a tantalum oxide, the effect is more remarkable. Further, the amount of energy input to the heater for applying thermal energy to the ink to discharge the ink from the orifice is E _op , and the minimum amount of energy input to the heater for discharging the ink is E E when the _th, when a value of _{E op / E th (= γ} ) sets the energy input to the heater so as to satisfy the following relationship, with scorching preventing effect can be more that more excellent, It was also found that the heater did not break, and that the ejection durability was excellent. 1.10 ≦ E _op / E _th ≦ 1.70

According to another embodiment of the third invention,
It contains (a) a colorant, (b) a liquid medium, and (e) an inkjet ink containing at least one compound selected from monoammonium citrate, diammonium citrate and triammonium citrate. An ink storage unit, and a recording unit having an inkjet recording head unit for discharging the ink from an orifice by the action of thermal energy, wherein the inkjet recording head includes a metal for applying thermal energy to the heater and a metal. A recording unit is provided that includes a heater having a top surface protection layer including a metal oxide.

[0028]

Next, the present invention will be described in more detail with reference to preferred embodiments. First, each component of the inkjet ink of the first to third aspects of the present invention will be described. [First Invention] The ink according to the first invention of the present invention will be described. The ink of the first invention comprises at least (a) a colorant, (b) a liquid medium, and (c) at least one or more kinds of ammonium salts of an acid having a methyl group or a methylene group and a carboxyl group. Contains compounds as constituents.

<(C) Ammonium salt of an acid having a methyl group or a methylene group and a carboxyl group> One feature of the ink according to the first invention is that the ink of the (c) includes a methyl group or a methylene group and a carboxyl group. It is to contain an ammonium salt of the acid as an essential component. The present inventors have conducted intensive studies on a method of reducing kogation adhered on a heater of the ink jet recording head in an ink jet recording method for discharging ink as ink droplets by the action of thermal energy. Alternatively, the present inventors have found that if at least one compound selected from ammonium salts of an acid having a methylene group and a carboxyl group is contained, generation of kogation can be reduced very effectively, and the present invention has been achieved. Furthermore, it was also found that the use of such an ink for ink jet did not cause a break in the heater of the recording head and significantly improved the ejection durability.

The ammonium salt of an acid having a methyl group or a methylene group and a carboxyl group is preferably one which hardly visually affects the color tone of the ink. That is, the acid is preferably one in which its own aqueous solution is at least visually uncolored. The acid preferably has 10 or less carbon atoms per molecule and 3 to 6 oxygen atoms per molecule. Specific examples of such acids include, for example, malonic acid, succinic acid, glutaric acid, adipic acid, lactic acid, malic acid, aspartic acid, glutamic acid, and the like.In the ink of the first invention of the present invention, Use ammonium salts.

The ammonium salt of an acid having a methyl group or a methylene group and a carboxyl group as described above is
Not only can they be used alone, but also two or more can be used in combination. In addition, the total content of at least one compound selected from ammonium salts of an acid having a methyl group or a methylene group and a carboxyl group is sufficient for a sufficient reduction of kogation and an ink jet suitability (clogging of an ink jet recording head). Taking into account the difficulty, the amount is 0.005 to 20% by weight, preferably 0.05 to 15% by weight, based on the total amount of the ink.

[Second Invention] Next, the ink according to the second invention will be described. The ink of the second invention is
It is characterized by containing at least one of (a) a coloring material, (b) a liquid medium, and (d) an ammonium aldonic acid salt.

<(D) Ammonium aldonic acid salt> One of the features of the ink according to the second invention is that it contains the ammonium aldonic acid salt (d) as an essential component. The present inventors have conducted intensive studies on a method for reducing the kogation adhered on a heater of the ink jet recording head in an ink jet recording method for discharging ink as ink droplets by the action of thermal energy. The present inventors have found that the generation of kogation can be reduced very effectively by including an ammonium salt, and the present invention has been accomplished. Furthermore, it was also found that the use of such an ink for ink jet did not cause a break in the heater of the recording head and significantly improved the ejection durability.

Aldonic acid is a polyoxycarboxylic acid corresponding to one obtained by oxidizing an aldehyde group of aldose to form a carboxyl group, and is represented by the following general formula.

[0035] (However, n is an integer of 0 or more. ^* C represents an asymmetric carbon atom.)

As described above, since aldonic acid has an asymmetric carbon atom, there are many optical isomers. Aldonic acids having 5 or more carbon atoms (n = 3 or more in the above general formula) rarely exist alone in an aqueous solution. Usually, a part of the aldonic acid is present between the γ- or δ-hydroxyl group. A lactone to form γ-aldonolactone and δ-aldonolactone, respectively, aldonic acid, γ-aldonolactone and δ
-Aldonolactone is said to exist as an equilibrium mixture of the three. And 4 carbon atoms (n = 2 in the above general formula)
It is rare that the aldonic acid alone is present in the aqueous solution alone, and usually, a part of the aldonic acid forms a lactone with the hydroxyl group at the γ-position to become γ-aldonolactone, respectively.
It is said to exist as an equilibrium mixture of aldonic acid and γ-aldonolactone.

Aldonic acid is classified by the number of carbon atoms and has 4 carbon atoms.
(N = 2 in the above general formula) is tetronic acid; one having 5 carbons (n = 3 in the above general formula) is pentonic acid; one having 6 carbons (n = 4 in the above general formula) Is collectively referred to as hexonic acid. Specific examples of aldonic acids include, for example,
Glycolic acid having 2 carbon atoms (n = 0 in the general formula) (alias: hydroxyacetic acid); 3 carbon atoms (n = 0 in the general formula)
Glyceric acid of 1); 4 carbon atoms (n =
2) erythronic acid, threonic acid; 5 carbon atoms (n = 3 in the above general formula) of ribbonic acid, arabonic acid, xylonic acid,
Lixonic acid; gluconic acid, allonic acid, altronic acid, mannonic acid, gulonic acid, idonic acid, galactonic acid, taronic acid having 6 carbon atoms (n = 4 in the above general formula); 7 carbon atoms (in the above general formula) n = 4) glucoheptonic acid and the like, and there are D-form, L-form and DL-form.

The ammonium salt of gluconic acid (n = 4 in the above general formula) among the ammonium salts of aldonic acid, which is a component of the ink of the second invention, will be described below. Gluconic acid is widely used as a food additive and is safe for the human body. Gluconic acid is rarely present alone in an aqueous solution, and usually, a part of gluconic acid forms a lactone with a hydroxyl group at the γ-position or δ-position, respectively, and γ-gluconolactone or δ- Gluconolactone is said to exist as an equilibrium mixture of gluconic acid, γ-gluconolactone and δ-gluconolactone. Gluconic acid exists in D-form, L-form, and DL-form, and any ammonium salt may be used. In general, D-gluconic acid in D-form is easily available. Also, as optical isomers of gluconic acid, allonic acid, altronic acid, mannonic acid, gulonic acid, idonic acid,
Galactonic acid, taronic acid and the like are present and exhibit properties similar to gluconic acid, and thus ammonium salts thereof may be used.

In the second invention, the above-mentioned ammonium salts of aldonic acids such as gluconic acid are used as essential components. However, the content of ammonium aldonic acid salts in the ink is sufficient to reduce kogation, In consideration of ink jet aptitude (such as difficulty in clogging of the ink jet recording head), the ratio of 0.
005 to 20% by weight.
The content is preferably set to 0.05 to 12% by weight.

[Third Invention] Next, the ink according to the third invention comprises at least (a) a colorant, (b) a liquid medium, and (e) monoammonium citrate, diammonium citrate and citrate. It contains at least one compound selected from triammonium acid as a component.

<(E) Monoammonium citrate, diammonium citrate, triammonium citrate> One feature of the ink according to the third invention is that (e) monoammonium citrate, diammonium citrate and It is to contain any of triammonium citrate as an essential component. The present inventors have conducted intensive studies on a method for reducing kogation adhered on a heater of the ink jet recording head in an ink jet recording method for discharging ink as ink droplets by the action of thermal energy. As a result, citric acid was added to the ink. The inventors have found that if at least one compound selected from monoammonium, diammonium citrate and triammonium citrate is contained, generation of kogation of the heater can be reduced very effectively, and the present invention has been achieved. Furthermore, it was also found that the use of the inkjet ink according to the third aspect of the present invention did not disconnect the heater of the recording head and significantly improved the ejection durability.

The mono-ammonium citrate, di-ammonium citrate and tri-ammonium citrate contained in the ink-jet ink of the third invention may be selected from these and used alone, or two or more of them may be used in combination. You can also. The total content of at least one compound selected from mono-ammonium citrate, di-ammonium citrate and tri-ammonium citrate in the ink of the third aspect of the present invention may be a sufficient effect of reducing kogation and ink jet suitability (ink jet recording head Is considered to be 0.005 with respect to the total amount of ink.
-20% by weight, more preferably 0.05-15% by weight based on the total amount of the ink.

Next, (a) a color material and (b) a liquid medium, which are common components of the inks according to the first to third aspects of the present invention, which contain the essential components having the respective characteristics described above, will be described. <(A) Coloring Material> As the coloring material of the ink of the present invention, a dye or a pigment can be used. (Dye) As the dye, any dye such as a direct dye, an acid dye, a basic dye, and a disperse dye can be used.

Specifically, for example, it can be appropriately selected from the following and used, but is not limited thereto. C. I. Direct Black-4, -9, -11, -17, -19, and-
22, -32, -80, -151, -154,
-168, -171, -194, -195,
C. I. Direct Blue-1, Same-2, Same-6, Same-
8, same -22, same -34, same -70, same -71, same -7
6, -78, -86, -142, -199, -200, -201, -202, -203,-
207, -218, -236, -287,

C. I. Direct Red-1, the same -2,
-4, -8, -9, -11, -13, -1
5, -20, -28, -31, -33, -3
7, -39, -51, -59, -62, -6
3, same -73, same -75, same -80, same -81, same -8
3, -87, -90, -94, -95, -9
9, -101, -110, -189, -22
5, 227, C.I. I. Direct Yellow-1, Same-2, Same-4, Same-8, Same-11, Same-12, Same-2
6, -27, -28, -33, -34, -4
1, -44, -48, -86, -87, -8
8, -132, -135, -142, -14
4,

C. I. Food Black-1, 2
C. I. Acid Black-1, Same-2, Same-7, Same-
16, same -24, same -26, same -28, same -31, same-
48, -52, -63, -107, -112,
-118, -119, -121, -172, -194, -208,

C. I. Acid Blue-1, -7, -9, -15, -22, -23, -27, and-
29, -40, -43, -55, -59,-
62, -78, -80, -81, -90,-
102, -104, -111, -185, -2
54,

C. I. Acid Red-1, Same -4, Same -8, Same -13, Same -14, Same -15, Same -18, Same-
21, -26, -35, -37, -52,-
249, -257, -289, C.I. I. Acid Yellow-1, Same -3, Same -4, Same -7, Same -11, Same-
12, -13, -14, -19, -23,-
25, -34, -38, -41, -42,-
44, -53, -55, -61, -71,-
76, -79,

C. I. Reactive Blue-1, same-
2, -3, -4, -5, -7, -8,-
9, -13, -14, -15, -17, -1
8, -19, -20, -21, -25, -2
6, -27, -28, -29, -31, -3
2, -33, -34, -37, -38, -3
9, same -40, same -41, same -43, same -44, same -4
6,

C. I. Reactive Red-1, same-
2, -3, -4, -5, -6, -7,-
8, same -11, same -12, same -13, same -15, same -1
6, -17, -19, -20, -21, and -2
2, 23, 24, 28, 29, -3
1, same -32, same -33, same -34, same -35, same -3
6, -37, -38, -39, -40, -4
1, Same -42, Same -43, Same -45, Same -46, Same -4
9, -50, -58, -59, -63, -6
4, same as -180,

C. I. Reactive Yellow-1 and-
2, -3, -4, -6, -7, -11,-
12, -13, -14, -15, -16, and-
17, same -18, same -22, same -23, same -24, same-
25, -26, -27, -37, -42, C.I.
I. Reactive Black-1, Same-3, Same-4, Same-
5, -6, -8, -9, -10, -12, -13, -14, -18, Projet Fast Cyan 2 (Zeneca), Projet Fast Magenta 2 ( Zeneca), Projet Fast Yellow 2 (Zeneca), Projet Fast Black 2 (Zeneca) and the like.

(Pigment) As the pigment, any pigment such as an inorganic pigment and an organic pigment can be used. In particular,
It can be appropriately selected and used from those listed below. However, it is not limited to this. Carbon black, C.I. I. Pigment Yellow-1, 2
-3, -12, -13, -14, -16, -17, -73, -74, -75, -83, -93, -95,- 97, -98, -114,
-128, -129, -151, -154, -195, C.I. I. Pigment Red-5, -7, -12, -48 (Ca), -48 (Mn), -5
7 (Ca), 57: 1, 57 (Sr), 112, 12
2, 123, 168, 184, 202, C.I. I. Pigment Blue-1, ditto-2, ditto-3, ditto-15: 3, ditto-
15:34, -16, -22, -60, C.I. I.
Vat Blue-4, -6.

(Dispersant) In the case where the above-mentioned pigments are used as the coloring material of the ink, a dispersant is used to stably disperse the pigment in the ink, as in the usual case. It is preferable that a pigment dispersion is prepared by previously mixing a pigment and a dispersant, and the obtained pigment dispersion is used as a coloring material. Examples of the dispersant that can be used at this time include a polymer dispersant and a surfactant dispersant listed below.

Examples of the polymer dispersant include polyacrylate, styrene-acrylic acid copolymer salt, styrene-methacrylic acid copolymer salt, styrene-acrylic acid-acrylic acid ester copolymer salt, styrene-acrylic acid copolymer salt. Maleic acid copolymer salt, acrylic acid ester-maleic acid copolymer salt, styrene-methacrylsulfonic acid copolymer salt, vinylnaphthalene-maleic acid copolymer salt, β-naphthalenesulfonic acid formalin condensate salt, polyvinylpyrrolidone , Polyethylene glycol, polyvinyl alcohol and the like can be used. Among them, the weight average molecular weight is 1,000 to 30,000 and the acid value is 100 to 4
A range of 30 is preferred. Examples of the surfactant-based dispersant include laurylbenzenesulfonate, laurylsulfonate, laurylbenzenecarboxylate, laurylnaphthalenesulfonate, aliphatic amine salts, polyethylene oxide condensates, and the like. The amount of these dispersants used is: pigment weight: dispersant weight = 10: 5-
It is preferred to be in the range of 10: 0.5.

(Self-dispersion type carbon black) In the ink of the present invention, for example, JP-A-5-15-1
It is also possible to use carbon black which is self-dispersible by introducing a hydrophilic group into the surface of carbon black as described in JP 86704 and JP-A-8-3498. If such a self-dispersible carbon black is used, it is not always necessary to use the above-mentioned dispersants.

The above-mentioned dyes and pigments used as the coloring material of the ink may be used alone, or
Two or more kinds may be used in combination. The concentration of these dyes and pigments is not limited, but is usually appropriately selected from the range of 0.1 to 20% by weight based on the total amount of the ink.

<(B) Liquid Medium> Next, the liquid medium constituting the ink-jet ink of the present invention will be described. In the present invention, it is preferable to use one containing water as a liquid medium of the ink, and it is particularly preferable to use a mixed solvent of water and a water-soluble organic solvent. The water used in the present invention is preferably not deionized water but general water containing various ions. The content of water is preferably in the range of 35 to 96% by weight based on the total amount of the aqueous ink. Water-soluble organic solvent used with water, to adjust the viscosity of the ink to a suitable suitable viscosity for use, to slow down the drying speed of the ink, or
It is used for various purposes such as to enhance the solubility of the color material and prevent clogging of the nozzles of the recording head.

As the water-soluble organic solvent used in the present invention, specifically, for example, methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol Alkyl alcohols having 1 to 5 carbon atoms such as isobutyl alcohol and n-pentanol; amides such as dimethylformamide and dimethylacetamide; ketones or keto alcohols such as acetone and diacetone alcohol; ethers such as tetrahydrofuran and dioxane Oxyethylene such as diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, polyethylene glycol, and polypropylene glycol; Or oxypropylene copolymer;
Ethylene glycol, propylene glycol, trimethylene glycol, triethylene glycol, 1,2,6
Alkylene glycols having an alkylene group containing 2 to 6 carbon atoms, such as hexanetriol; glycerin; trimethylolethane, trimethylolpropane; ethylene glycol monomethyl (or ethyl) ether, diethylene glycol monomethyl (or ethyl) ether,
Lower alkyl ethers such as 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; monoethanolamine; Alkanolamines such as diethanolamine and triethanolamine; sulfolane, N-methyl-2
-Pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2
-Imidazolidinones and the like. The water-soluble organic solvents as described above can be used alone or as a mixture.

<Additives> Further, in addition to the above-mentioned components, if necessary, various conventionally known general additives such as a viscosity modifier, lithium hydroxide and water may be added to the ink of the present invention. PH of sodium oxide, potassium hydroxide, aqueous ammonia, acetic acid, sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid and salts thereof
An adjusting agent, a fungicide, a preservative, an antioxidant, an antifoaming agent, a surfactant, and a nozzle drying inhibitor such as urea can be appropriately used in combination.

<Physical Properties of Ink> The ink of the present invention having the above composition is suitably used for ink jet recording. Therefore, a preferable range of the physical properties of the ink is a pH around 25 ° C., preferably 3 to 12, more preferably 4 to 10, and a surface tension of preferably 10 to 60 m.
N / m (dyn / cm), more preferably 15 to 50 m
N / m (dyn / cm), viscosity is preferably 1 to 30 c
ps, more preferably in the range of 1 to 10 cps.

<Ink-Jet Recording Method> As a recording method capable of obtaining a good effect when recording is performed using the ink of the present invention, a thermal energy corresponding to a recording signal is applied to ink in a room of a recording head. This is an ink jet recording method in which droplets are generated by energy. A recording apparatus in which the ink of the present invention is preferably used will be described below with reference to the drawings.

(Recording Method) Next, the ink-jet recording method of the present invention using the ink-jet ink of the present invention having the above-described first to third aspects will be described. First, an example of a head configuration which is a main part of an ink jet recording apparatus using thermal energy is shown in FIG. 1 and FIG. FIG. 1 shows a head 13 along an ink flow path.
2 is a cross-sectional view taken along line AB in FIG. The head 13 has a flow path (nozzle) 14 through which ink passes.
The heating element substrate 15 is obtained by bonding a glass, ceramic, silicon, polysulfone or plastic plate or the like having the above. The heating element substrate 15 has a protective layer 16-made of silicon oxide, silicon nitride, silicon carbide, or the like.
1, a metal oxide such as a metal such as platinum or a platinum oxide;
Preferably, the outermost surface protective layer 16-2 formed of tantalum or a tantalum oxide or the like, and the electrodes 17-1 and 17 formed of aluminum, gold, an aluminum-copper alloy, or the like
-2, a heating resistor layer 18 formed of a high melting point material such as hafnium boride, tantalum nitride, and tantalum aluminum; a heat storage layer 19 formed of silicon oxide and aluminum oxide; a heat radiation of silicon, aluminum, aluminum nitride, and the like The substrate 20 is made of a material having good properties.

The electrodes 17-1 and 17- of the head 13
When a pulse-like electric signal is applied to the heating element 2, an area (heater) indicated by n on the heating element substrate 15 rapidly generates heat, bubbles are generated in the ink 21 in contact with the surface, and the meniscus is generated by the pressure. 23 protrudes, the ink 21 is ejected through the nozzle 14 of the head, becomes an ink droplet 24 from the ejection orifice 22, and flies toward the recording material 25.
FIG. 3 shows an external view of an example of a multi-head in which many heads shown in FIG. 1 are arranged. This multi-head is formed by bonding a glass plate 27 having a multi-nozzle 26 and a heating head 28 similar to that described in FIG.

(Energy Amount Applied to Heater) Next, γ
The values will be described. The γ value is a factor that represents the ratio of the energy actually input to the critical energy at which the bubble jet head can discharge the marginally. That is, when the width of the pulse applied to the bubble jet head is P (the total width when a plurality of pulses are divided and applied), the applied voltage is V, and the resistance of the heater is R, the input energy E is It is represented by the following formula (A). ^{E = P × V 2 / R} (A) At this time, the energy of the minimum required heater bubble jet head can be barely discharged as E _th, if a and E _op-up energy when actually performing the drive, The γ value is
It is given by the following equation (B). γ = E _op / E _th (B)

As a method of obtaining the γ value from the driving conditions of the bubble jet head, the following (1) is practically used.
And (2). (1) When the pulse width is fixed First, an appropriate voltage to be ejected by the bubble jet head is found and driven with a given pulse width. Next, the voltage is gradually lowered to find a voltage at which the discharge stops. The minimum dischargeable voltage immediately before this voltage is _Vth . Assuming that the voltage actually used in the driving is V _op , the γ value is obtained by the following equation (C). γ = (V _op / V _th ) ² (C)

(2) When the Voltage is Fixed First, at a given voltage, an appropriate pulse width to be ejected by the bubble jet head is found and driven. Next, the pulse width is gradually reduced to find a pulse width at which ejection stops. The minimum pulse width that can be ejected immediately before this pulse width is _Pth . The pulse width actually used in driving is P
Assuming _op , the γ value is obtained by the following equation (D). γ = P _op / P _th (D)

Here, the voltage value is a voltage actually applied to the heater section for causing the bubble jet heater to generate heat. Since a voltage applied from outside the head may drop at a contact point, a wiring resistance, or the like, it cannot be used for calculating the γ value in a strict sense. However, when V _th and V _op are measured from outside the head, these voltage fluctuations are included in both values and measured. Therefore, unless the voltage fluctuations are large, γ is directly used by these values. Even if the value is calculated, the error is small, and the value based on the error can be used as the γ value for convenience.

Also, when printing is performed by an actual printer, it is necessary to pay attention to the fact that since a plurality of heaters are driven, the voltage for one heater may be affected by this and may fluctuate. is there. Further, equations (A) and (B)
Thus, at the same γ value, the square of V and P seem to be inversely proportional, but in reality, electrical problems such as a non-rectangular pulse waveform, and a different pulse waveform result in different heat diffusion around the heater. The square of V and P are not in a simple relationship due to thermal problems such as the above, and problems specific to bubble jets such as a change in the heat flux from the heater to the ink when the voltage is different and a change in the foaming state. Therefore, the methods described in the above (1) and (2) must be handled independently, and it is noted that converting from one value to the other by calculation may cause an error. Must. In the present invention, unless otherwise specified, the value determined by the above method (1) was used as the γ value.

For stable ejection of the ink, it is general to drive the ink under the condition that the γ value defined as above is about 1.12 to 1.96. However, in the case of an ink jet recording method using the ink for ink jet recording according to the first invention of the present invention and applying thermal energy to the ink to discharge the ink from a recording head, the γ value is set in a predetermined range, specifically, , 1.10 to 1.75 are preferably driven. Depending on such driving conditions,
Sticking of kogation to the heater is further prevented, and the life of the recording head can be further extended.

The (c) ammonium salt of an acid having a methyl group or a methylene group and a carboxyl group, which is an essential component of the ink of the first invention, can be used as a heater for the heater when an image is formed under a high γ value. There is a tendency that the metal of the surface protective layer and the oxide of the metal are eroded to destroy the heater and shorten the life of the inkjet recording head. The details of why the outermost protective layer of the heater is eroded when the γ value is high are not well understood, but when the γ value is high, energy is excessively supplied to the heater, which results in an excessively high heater temperature. Is probably the cause. That is, it is considered that the higher the temperature of the outermost protective layer, the more easily the metal is eroded by the ammonium salt of an acid having a methyl group or a methylene group and a carboxyl group, and therefore, the inkjet recording using the ink of the first invention is considered. In the method, as described above, it is preferable to drive in the range where the γ value is 1.10 to 1.75.

Regarding this γ value, the ammonium aldonic acid salt (d), which is an essential component in the ink according to the second invention, has a high γ value, the metal or / and metal oxide of the outermost protective layer of the heater. Erosion tends to shorten the life of the inkjet recording head. The details of why the outermost protective layer of the heater is eroded when the γ value is high are not well understood, but when the γ value is high, the heater is excessively supplied with energy, and thus the heater temperature is excessively high. This is probably the cause. That is, it is considered that the higher the temperature of the outermost protective layer is, the more easily the metal is eroded by the ammonium aldonic acid salt. Therefore, in the case of the inkjet recording method using the ink according to the second invention of the present invention, the γ value is 1.10 to 10.
It is preferable to control and drive the heater so as to be in the range of 1.90.

Further, (e) monoammonium citrate, diammonium citrate and triammonium citrate, which are essential components of the ink according to the third invention, are all γ.
When an image is formed under a condition with a high value, the metal and the oxide of the metal on the outermost surface protective layer of the heater tend to be eroded, destroying the heater and shortening the life of the ink jet recording head. The details of why the outermost protective layer of the heater is eroded when the γ value is high are not well understood, but when the γ value is high, energy is excessively supplied to the heater, which results in an excessively high heater temperature. Is probably the cause. That is, it is considered that the higher the temperature of the outermost surface protective layer, the more easily the metal is eroded by monoammonium citrate, diammonium citrate and triammonium citrate. When used, it is preferable to control and drive the heater so that the γ value is in the range of 1.10 to 1.70.

<Inkjet Recording Apparatus> FIG. 4 shows an example of an inkjet recording apparatus that can be used in the present invention.
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. Blade 61
Are arranged at positions adjacent to a recording area of the recording head 65, and in the case of the apparatus example shown in FIG.

Reference numeral 62 denotes a cap on the protruding opening surface of the recording head 65, which is disposed at a home position adjacent to the blade 61, moves in a direction perpendicular to the moving direction of the recording head 65, and comes into contact with the ink discharge port surface. And a configuration for performing capping. Further, reference numeral 63 denotes an ink absorber provided adjacent to the blade 61, which is held in a form protruding into the movement path of the recording head 65, similarly to the blade 61. The blade 61, the cap 62, and the ink absorber 63 constitute an ejection recovery unit 64, and the blade 6
1 and the ink absorber 63 remove water, dust, and the like from the ejection port surface.

Reference numeral 65 denotes a discharge energy generating means,
A recording head 66 performs recording by discharging ink onto a recording material opposed to a discharge port surface provided with discharge ports, and 66 is a carriage for mounting the recording head 65 and moving the recording head 65. is there. The carriage 66 is slidably engaged with the guide shaft 67, and a part of the carriage 66 is connected to a belt 69 driven by a motor 68 (not shown). As a result, the carriage 66 can move along the guide shaft 67, and the recording head 65 can move the recording area and the adjacent area.

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

When capping is performed with the cap 62 in contact with the ejection surface of the recording head 65, the cap 62
Moves so as to protrude into the movement 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 positions as the positions at the time of the wiping described above. As a result, the ejection port surface of the recording head 65 is also wiped during this movement. The above-described movement of the print head to the home position is performed not only at the end of printing or at the time of ejection recovery,
While the recording head moves through the recording area for recording, it moves to a home position adjacent to the recording area at a predetermined interval, and the wiping is performed in accordance with this movement.

FIG. 5 is a view showing an example of an ink cartridge containing ink supplied to a recording head via an ink supply member, for example, a tube. Here, reference numeral 40 denotes an ink storage section storing the supply ink, for example, an ink bag, and a rubber stopper 42 is provided at the tip thereof. By inserting a needle (not shown) into this stopper 42,
The ink in the ink bag 40 can be supplied to the head. 4
Reference numeral 4 denotes an ink absorber for receiving waste ink. The ink container preferably has a liquid contact surface with ink formed of polyolefin, particularly polyethylene.

The ink jet recording apparatus of the present invention is not limited to the one in which the head and the ink cartridge are separated as described above, but may be an integrated one as shown in FIG. In FIG. 6, reference numeral 70 denotes a recording unit, in which an ink container containing ink, for example, an ink absorber is stored, and the ink in the ink absorber is transferred from a head unit 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. Further, a structure may be used in which the ink storage unit is an ink bag in which a spring or the like is provided 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.

[0080]

Next, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to the following examples unless it exceeds the gist thereof. In the following description, “parts” and “%” are based on weight unless otherwise specified.

[A: Examples, Reference Examples, and Comparative Examples according to the First Invention] <Examples A-1 to A-3 and Comparative Example A ″ -1> After stirring and dissolving, the mixture was filtered under pressure with a micro filter having a pore size of 0.2 μm (manufactured by Fuji Photo Film Co., Ltd.) to prepare the ink of Example A-1 and the ink of Comparative Example A ″ -1. did.

[0082]

<Evaluation 1> An on-demand type multi-recording head BC-02 (Canon (Canon) which ejects ink by applying thermal energy according to a recording signal to the ink using the ink of the above-described embodiment A-1. Co., Ltd .: The outermost protective layer on the heater is composed of tantalum and an oxide of tantalum), and the ink was ejected under the following conditions to evaluate. In Example A-1, the ink ejection conditions of the inkjet recording apparatus are as follows: pulse width 1.1 μs (on) +3.0 μs (off) +3.2.
V _th (critical voltage just before ejection) was actually measured at μs (on) and a driving frequency of 6,250 Hz, and γ value = 1.39.
The ink was ejected by applying V _op (driving voltage) corresponding to. Then, the ejection durability of the ink jet recording head and the kogation on the heater when ink jet recording was performed under these conditions were evaluated by the following methods and criteria, respectively. The results are shown in Table 1. Incidentally, V _op (drive voltage) was calculated by the following equation. V _op = √γ × V _th

(1) Ejection Durability The ink of Example A-1 was continuously ejected under the same driving conditions as the above apparatus, and droplets ejected from the recording head every 1 × 10 ⁶ were collected in a container. Weighed with an electronic balance.
The average amount of ejected droplets at 1 × 10 ⁶ shots was calculated from the increased amount of the container. In addition, continuous discharge is performed up to 1 × 10 ⁸
The evaluation was performed based on the following criteria, and the results are shown in Table 1.

A: The average amount of ejected droplets between 9.9 × 10 ^{7 and} 1 × 10 ⁸ shots is 90% or more of the average amount of ejected droplets after 0 to 1 × 10 ⁶ shots. B: The average ejected droplet amount between 9.9 × 10 ^{7 and} 1 × 10 ⁸ shots is less than 90% and 70% or more as compared with the average ejected droplet amount after 0 to 1 × 10 ⁶ shots. C: The average ejected droplet amount between 9.9 × 10 ^{7 and} 1 × 10 ⁸ shots is less than 70% compared to the average ejected droplet amount after 0 to 1 × 10 ⁶ shots. D: Discharge failed on the way.

(2) Amount of kogation adhering The recording head used in the above-described head discharge durability evaluation was disassembled after completion, and the heater surface of the nozzle used for discharge durability was visually observed with an optical microscope (400 times magnification). The kogation adhesion amount was evaluated according to the following criteria. A: Almost no kogation is observed. B: Slight adhesion of kogation is observed. C: Many kogation adheres. D: Very much kogation is observed.

A similar evaluation was performed using the ink of Example A-1 at a V _op (drive voltage) corresponding to a γ value of 1.10. V corresponding to 71
_op (drive voltage) was evaluated in the same manner as in Example A-3.
The evaluation was performed in the same manner as described above, and the results are shown in Table 1. Reference Example A'-1 was prepared by using the ink of Example 1 and discharging the ink at V _op (drive voltage) corresponding to a γ value of 1.80. Furthermore, the ink of Comparative Example A ″ -1 containing no 50% aqueous solution of ammonium lactate in the ink composition of Example A-1 was used, and a V _op (driving voltage) equivalent to γ = 1.39 was used. Is evaluated,
The results are shown in Table 1.

[0088]

[Table 1]

<Examples A-4 to A-15> Further, the following components were mixed, sufficiently stirred and dissolved, and then a micro filter having a pore size of 0.2 μm (manufactured by Fuji Photo Film Co., Ltd.) Example A-4 to A-10
Was prepared. Further, after preparing a pigment dispersion using the components shown below, the pigment inks of Examples A-11 to A-14 were prepared using the dispersion as a coloring material.

[0090]

[0091]

[0092]

[0093]

[0094]

[0095]

[0096]

[0097]

The above components were mixed and mixed in a water bath at 70
Heat to ° C. to completely dissolve the resin component. To this solution, 15 parts of carbon black “MA-100” (pH 3.5; manufactured by Mitsubishi Chemical Corporation) and 5 parts of 2-propanol were added.
After premixing for 30 minutes, dispersion treatment was performed under the following conditions. -Disperser: Sand glider (made by Igarashi Kikai)-Grinding media: zirconium beads 1 mm diameter-Filling ratio of the grinding media: 50% (volume)-Grinding time: 3 hours Further, centrifugation treatment (12,000 rpm, 20 minutes)
Was performed to remove the coarse particles to obtain a pigment dispersion liquid 1.

(Preparation of Ink) The following components including the pigment dispersion obtained above were mixed in a beaker and stirred at 25 ° C. for 3 hours. Example A used in the first invention
-11 ink.・ 30 parts of pigment dispersion liquid ・ 10 parts of diethylene glycol ・ 2 parts of 2-propanol ・ 2 parts of 50% aqueous solution of ammonium lactate ・ 56 parts of water

(Preparation of Ink of Example A-12) (Preparation of Pigment Dispersion Liquid 2) 300 g of commercially available acidic carbon black "MA77" (pH 3; manufactured by Mitsubishi Chemical Corporation) was well mixed in 1,000 ml of water. Thereafter, 450 g of sodium hypochlorite (effective chlorine concentration 12%) was added dropwise thereto, and
The mixture was stirred at 00 to 105 ° C for 10 hours. The obtained slurry was filtered with Oriental filter paper No. 2 (manufactured by Advantis), and the pigment particles were sufficiently washed with water. This pigment wet cake was redispersed in 3,000 ml of water and desalted with a reverse osmosis membrane until the electric conductivity was 0.2 μs. Further, the pigment dispersion (pH = 8 to 1)
0) was concentrated to a pigment concentration of 10% by weight. The -COONa group was introduced on the surface of carbon black by the above method.

(Preparation of Ink) The following components including the pigment dispersion obtained above were mixed in a beaker and stirred at 25 ° C. for 3 hours. This mixture was prepared with a pore size of 3.0 μm.
Was filtered under pressure using a membrane filter (manufactured by Sumitomo Electric Industries, Ltd.) as the ink of Example A-12 used in the first invention. -30 parts of pigment dispersion 2-5 parts of glycerin-5 parts of trimethylolpropane-0.2 parts of acetylene glycol ethylene oxide adduct (trade name: acetylenol EH, manufactured by Kawaken Fine Chemical)-2 parts of 50% ammonium lactate aqueous solution- 57.8 parts of water

(Preparation of Ink of Example A-13) (Preparation of Pigment Dispersion Liquid 3) Styrene-acrylic acid copolymer (acid value 200, average molecular weight 7,000) 5.5 parts Monoethanolamine 1 0.0 parts ・ Ion-exchanged water 67.5 parts ・ Diethylene glycol 5.0 parts

The above components were mixed, and mixed in a water bath.
The mixture was heated to ° C. to completely dissolve the resin. To this solution was added C.I. I. Pigment Yellow 93 20
And isopropyl alcohol (1.0 part), premixed for 30 minutes, and then dispersed under the following conditions.

-Dispersing machine: sand grinder-Grinding media: glass beads 1 mm diameter-Filling rate of the grinding media: 50% (volume)-Grinding time: 3 hours Further centrifugation (12,000 rpm, 20 minutes) was performed. The coarse particles were removed to obtain a dispersion.

(Preparation of Ink) The following components including the pigment dispersion obtained above were mixed in a beaker and stirred at 25 ° C. for 3 hours. Example A used in the first invention
-13 ink.

(Preparation of Ink of Example A-14) (Preparation of Pigment Dispersion Liquid 4) Styrene-acrylic acid copolymer (acid value 200, average molecular weight 7,000) 5.5 parts Monoethanolamine 1 0.0 parts ・ Ion-exchanged water 67.5 parts ・ Diethylene glycol 5.0 parts

The above components were mixed and mixed in a water bath at 70
The mixture was heated to ° C. to completely dissolve the resin. To this solution was added C.I. I. Pigment Red 122 (20 parts) and isopropyl alcohol (1.0 part) were added, and premixing was performed for 30 minutes, followed by dispersion treatment under the following conditions.

-Dispersing machine: sand grinder-Grinding media: glass beads 1 mm diameter-Filling rate of grinding media: 50% (volume)-Grinding time: 3 hours Further centrifugation treatment (12,000 rpm, 20 minutes) was performed. The coarse particles were removed to obtain a dispersion.

(Preparation of Ink) Example A in which the following components including the pigment dispersion obtained above were mixed in a beaker and stirred at 25 ° C. for 3 hours was used in the first invention.
-14 ink.

(Preparation of Ink of Example A-15) (Preparation of Pigment Dispersion Liquid 5) 5.5 parts of styrene-acrylic acid copolymer (acid value 200, average molecular weight 7,000) Monoethanolamine 1 0.0 parts ・ Ion-exchanged water 67.5 parts ・ Diethylene glycol 5.0 parts

The above components were mixed and mixed in a water bath.
The mixture was heated to ° C. to completely dissolve the resin component. To this solution was added C.I. I. Pigment Blue 15: 3 to 20
And 1.0 part of isopropyl alcohol, and after premixing for 30 minutes, a dispersion treatment was performed under the following conditions.

-Dispersing machine: sand grinder-Grinding media: glass beads 1 mm diameter-Filling ratio of grinding media: 50% (volume)-Grinding time: 3 hours Further centrifugation treatment (12,000 rpm, 20 minutes) was performed. The coarse particles were removed to obtain a dispersion.

(Preparation of Ink) The following components including the pigment dispersion obtained above were mixed in a beaker and stirred at 25 ° C. for 3 hours. Example A used in the first invention
-15 ink.

<Comparative Examples A ″ -2 to A ″ -11> The following components were mixed, sufficiently stirred and dissolved, and then a micro filter having a pore size of 0.2 μm (Fuji Photo Film Co., Ltd.) Comparative Example A ''-2 ~
A ″ -6 inks were each prepared. Further, Example A-
The pigment inks of Comparative Examples A ″ -7 to A ″ -11 were prepared using the pigment dispersions prepared in 11 to A-15.

[0115]

[0116]

[0117]

[0118]

[0119]

(Preparation of Ink of Comparative Example A ″ -7) The following components were mixed in a beaker and stirred at 25 ° C. for 3 hours to obtain an ink of Comparative Example A ″ -7. -30 parts of pigment dispersion liquid used in the examples-10 parts of diethylene glycol-2 parts of 2-propanol-58 parts of water

(Preparation of Ink of Comparative Example A ″ -8) The following components were mixed in a beaker and stirred at 25 ° C. for 3 hours. This mixture was subjected to pressure filtration with a membrane filter having a pore size of 3.0 μm (manufactured by Sumitomo Electric Industries, Ltd.) to obtain an ink of Comparative Example A ″ -8. -30 parts of pigment dispersion liquid used in Examples-5 parts of glycerin-5 parts of trimethylolpropane-0.2 parts of acetylene glycol ethylene oxide adduct (trade name: acetylenol EH, manufactured by Kawaken Fine Chemical)-Water 59. 8 copies

(Preparation of Ink of Comparative Example A ″ -9) The following components were mixed in a beaker and stirred at 25 ° C. for 3 hours to obtain an ink of Comparative Example A ″ -9.

(Preparation of Ink of Comparative Example A ″ -10) The following components were mixed in a beaker and stirred at 25 ° C. for 3 hours to obtain an ink of Comparative Example A ″ -10.

(Preparation of Ink of Comparative Example A ″ -11) The following components were mixed in a beaker and stirred at 25 ° C. for 3 hours to obtain an ink of Comparative Example A ″ -11.

<Evaluation 2> The above Examples A-4 to A-15
And an on-demand multi-recording head BC-02 (Canon Inc.) which ejects ink by applying thermal energy according to a recording signal to the ink of Comparative Examples A "-2 to A" -11. Manufactured by using an ink jet recording apparatus having an outermost protective layer on the heater made of tantalum and an oxide of tantalum, and discharging ink under the following conditions. The ink ejection conditions of the ink jet recording apparatus are as follows: pulse width 1.1 μs (on) +3.
At 0 μs (off) +3.2 μs (on) and a driving frequency of 6,250 Hz, V _th (critical voltage just before ejection) is actually measured, and V _op (driving voltage) corresponding to γ value = 1.39 is applied. The ink was ejected. Then, when ink jet recording is performed under these conditions, the ejection durability of the ink jet recording head and the kogation to the heater are determined.
Evaluation was performed by the same method and criteria as in <Evaluation 1>. The results are shown in Tables 2 and 3.

[0126]

[Table 2]

[0127]

[Table 3]

[B: Examples, Reference Examples, and Comparative Examples according to the Second Invention] <Examples B-1 to B-3, Reference Examples B′-1 and B′-
2. Comparative Example B ″ -1> The following components were mixed, sufficiently stirred and dissolved, and then filtered under pressure through a 0.2 μm pore size microfilter (manufactured by Fuji Photo Film Co., Ltd.). Thus, inks of Example B-1 and Comparative Example B ″ -1 were prepared by removing ammonium gluconate from the ink compositions of Example B-1.

[0129]

[0130]

<Evaluation 1> Using the same apparatus as described in [Evaluation 1] of Example A-1 above, the ink of Example B-1 was used to obtain a V value corresponding to a γ value of 1.39. _op (drive voltage) was applied to eject the ink. As a result, Example B
It was confirmed that the ink of No. -1 was comparable to a normal inkjet ink and could be sufficiently used as an inkjet ink. Further, the ink of Example B-1 obtained above was used to eject ink at V _op (drive voltage) corresponding to a γ value of 1.10 in Example B.
In the same manner, Example B-3 ejected ink at V _op (drive voltage) corresponding to a γ value of 1.90.

Using the ink of Example B-1, the γ value
V corresponding to 1.92_op(Drive voltage) to eject ink
The result corresponds to Reference Example B'-1, where the γ value is 1.96.
V _opReference example: Ink discharged at (drive voltage)
B'-2. Further, from the ink of Example B-1,
Ammonium gluconate except for ammonium ruconate
Prepare ink of Comparative Example B ″ -1 in which a considerable amount was supplemented with water,
The ink has a V value corresponding to a γ value of 1.39._op(Drive power
(Comparative Example B ″ -1). And for each
Then, evaluation was performed by the same method and criteria as in Example B-1.
Was. Table 4 shows the results.

[0133]

[Table 4]

<Examples B-4 to B-16> Using the components shown below, a pigment ink was prepared by mixing each component with a dispersion liquid containing each pigment, and then having a pore size of 3 μm. It was produced by pressure filtration using a micro filter (manufactured by Sumitomo Electric Industries, Ltd.). For each of the dye inks, the following components are mixed, sufficiently stirred and dissolved, and then pressure-filtered using a micro filter having a pore size of 0.2 μm (manufactured by Fuji Photo Film Co., Ltd.). do it,
Each color ink was prepared. Table 5 shows Example B-4.
The main compositions of the inks of Nos. To B-16 are shown below.

[0135]

[0136]

[0137]

[0138]

(Ink Composition of Example B-8) C.I. I. Food Black 2 3 parts-Glycerin 5 parts-Ethylene glycol 10 parts-2-propanol 3 parts-Ammonium gluconate 0.5 part-Water 78.5 parts

(Ink Composition of Example B-9) C.I. I. Reactive Red 180 2.5 parts-Glycerin 5 parts-Ethylene glycol 10 parts-2-propanol 3 parts-Ammonium gluconate 0.2 parts-Water 79.3 parts

(Ink Composition of Example B-10) C.I. I. Direct Blue 199 3 parts-Glycerin 5 parts-Ethylene glycol 10 parts-2-propanol 3 parts-Ammonium gluconate 0.5 part-Water 78.5 parts

[0142]

(Preparation of Ink of Example B-12) Example A
Pigment Dispersion Liquid 1 was prepared in the same manner as in -11, and was used to prepare the ink of Example B-12. The following components were mixed in a beaker, and stirred at 25 ° C. for 3 hours to obtain an ink of Example B-12. (Ink composition of Example B-12)-30 parts of pigment dispersion liquid-10 parts of diethylene glycol-2 parts of 2-propanol-1 part of ammonium gluconate-57 parts of water

(Preparation of Ink of Example B-13) Example A
Pigment dispersion liquid 2 was prepared in the same manner as in Example B-12, and Example B-
Thirteen inks were prepared. The following components were mixed in a beaker and stirred at 25 ° C. for 3 hours. This mixture was subjected to a micro filter having a pore size of 3.0 μm (Sumitomo Electric Industries, Ltd.)
Was subjected to pressure filtration as in Example B-13. (Ink composition of Example B-13) Pigment dispersion 2 30 parts Glycerin 5 parts Trimethylolpropane 5 parts Acetylene glycol ethylene oxide adduct (trade name: acetylenol EH, manufactured by Kawaken Fine Chemical) 0.2 Parts ・ 1 part of ammonium gluconate ・ 58.8 parts of water

(Preparation of Ink of Example B-14) Example A
Pigment dispersion 3 was prepared in the same manner as in -13, and Example B-14 was prepared using this. Example B was prepared by mixing the following components in a beaker and stirring the mixture at 25 ° C. for 3 hours.
-14 ink.

(Preparation of Ink of Example B-15) Example A
Pigment dispersion liquid 4 was prepared in the same manner as in -14, and the ink of Example B-15 was prepared using this. The following components were mixed in a beaker, and stirred at 25 ° C. for 3 hours to obtain an ink of Example B-15.

(Preparation of Ink of Example B-16) Example A
Pigment Dispersion 5 was prepared in the same manner as -15, and the ink of Example B-16 was prepared using this. The following components were mixed in a beaker, and stirred at 25 ° C. for 3 hours to obtain an ink of Example B-16.

[0148]

[Table 5]

<Comparative Examples B "-2 to B"-6> The ammonium aldonic acid salts were removed from the compositions of the inks of Examples B-4 and B-8 to B-11. The inks of Comparative Examples B ″ -2 to B ″ -6 were prepared in the same manner as in Examples B-4 and B-8 to B-11, except that the inks were replaced.

<Evaluation 2> The above Examples B-4 to B-16
The inks of Comparative Examples B ″ -2 to B ″ -6 were evaluated by the same method and criteria as in <Evaluation 2>.

<Evaluation Results> As a result of the above evaluation, Example B
In each of -4 to B-16, both the ejection durability and the kogation adhesion amount were evaluated as rank A. In addition, other ink jet recording characteristics were not inferior to ordinary ink jet inks, and it was confirmed that the ink jet recording inks can be sufficiently used as ink jet inks. On the other hand, Comparative Example B "-2 to B"
Each of the inks of -6 was evaluated to be rank B or lower in both ejection durability and kogation adhesion amount.

[C: Examples, Reference Examples, and Comparative Examples according to the Third Invention] <Examples C-1 to C-3 and Comparative Example C ″ -1> After stirring and dissolving, the mixture was filtered under pressure with a micro filter having a pore size of 0.2 μm (manufactured by Fuji Photo Film Co., Ltd.) to prepare an ink of Example C-1 and an ink of Comparative Example C ″ -1. did.

[0153]

[Evaluation 1] Using the same apparatus as described in [Evaluation 1] of Example A-1 above, the ink of Example C-1 was used to obtain V _op corresponding to a γ value of 1.39. (Drive voltage)
To discharge the ink. The ejection durability of the inkjet recording head and the adhesion of kogation to the heater when inkjet recording was performed under these conditions were evaluated by the same method and criteria as in [Evaluation 1] of Example A-1. Table 6 shows the results.

A similar evaluation was performed using the ink of Example C-1 at a V _op (drive voltage) corresponding to a γ value of 1.10. V corresponding to 61
_op (drive voltage) was evaluated in the same manner as in Example C-3.
The results evaluated in the same manner as above are shown in Table 6.
A reference example C′-1 was similarly evaluated using the ink of Example C-1 at V _op (drive voltage) corresponding to a γ value of 1.80. Further, the ink of Example C-1 was prepared by removing the triammonium citrate from the ink of Example C-1, and preparing an ink of Comparative Example C ″ -1 in which the triammonium citrate was supplemented with water. V corresponding to 1.39
The same evaluation as above was performed with _op (drive voltage). Table 6 shows the results.

[0156]

[Table 6]

<Examples C-4 to C-14> Furthermore, the following components were mixed, sufficiently stirred and dissolved, and then a micro filter having a pore size of 0.2 μm (manufactured by Fuji Photo Film Co., Ltd.) To obtain inks of Examples C-4 to C-9. Further, a pigment dispersion was prepared using the components shown below, and the dispersion was used to prepare Example C-1.
Pigment inks of 0 to C-14 were prepared.

[0158]

[0159]

[0160]

[0161]

[0162]

[0163]

(Preparation of Ink of Example C-10) A pigment dispersion 1 was prepared in the same manner as in Example A-11, and was used to prepare an ink of Example C-10. The following components were mixed in a beaker and stirred at 25 ° C. for 3 hours to obtain an ink of Example C-10 used in the third invention. (Ink composition of Example C-10) Pigment dispersion 1 30 parts Diethylene glycol 10 parts 2-propanol 2 parts Triammonium citrate 1 part Water 57 parts

(Preparation of Ink of Example C-11) Pigment dispersion liquid 2 was prepared in the same manner as in Example A-12, and used to prepare the ink of Example C-11. The following components were mixed in a beaker and stirred at 25 ° C. for 3 hours. This mixture was filtered under pressure with a membrane filter having a pore size of 3.0 μm (manufactured by Sumitomo Electric Industries, Ltd.) to obtain an ink of Example C-11 used in the third invention. (Ink composition of Example C-11) Pigment dispersion 2 30 parts Glycerin 5 parts Trimethylolpropane 5 parts Acetylene glycol ethylene oxide adduct (trade name: acetylenol EH, manufactured by Kawaken Fine Chemical) 0.2 Parts-Triammonium citrate 1 part-Water 58.8 parts

(Preparation of Ink of Example C-12) A pigment dispersion 3 was prepared in the same manner as in Example A-13, and was used to prepare an ink of Example C-12. The following components were mixed in a beaker and stirred at 25 ° C. for 3 hours to obtain an ink of Example C-12 used in the third invention.

(Preparation of Ink of Example C-13) Pigment dispersion liquid 4 was prepared in the same manner as in Example A-14, and was used to prepare the ink of Example C-13. The following components were mixed in a beaker and stirred at 25 ° C. for 3 hours to obtain an ink of Example C-13 used in the third invention.

(Preparation of Ink of Example C-14) A pigment dispersion 5 was prepared in the same manner as in Example A-15, and was used to prepare an ink of Example C-14. The following components were mixed in a beaker and stirred at 25 ° C. for 3 hours to obtain an ink of Example C-14 used in the third invention.

<Comparative Example C ″ -2> The following components were mixed and sufficiently stirred to dissolve, and then the mixture was mixed with a pore size of 0.2.
μm micro filter (Fuji Photo Film Co., Ltd.)
To obtain an ink of Comparative Example C ″ -2.

[0170]

<Evaluation 2> The above Examples C-4 to C-14
The ink of Comparative Example C ″ -2 was evaluated by the same method and criteria as in <Evaluation 2>. Table 7 shows the results.

[0172]

[Table 7]

[0173]

As described above, according to the present invention,
In inkjet recording using thermal energy,
Ink jet ink capable of effectively reducing kogation on a heater of a recording head and further improving the life of the recording head, a method of reducing kogation on a heater of an ink jet recording head, an ink jet recording method, and an ink jet recording apparatus And a method for extending the life of the inkjet recording unit and the recording head.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an example of a recording head of an ink jet recording apparatus of the present invention.

FIG. 2 is a cross-sectional view illustrating an example of a recording head of the inkjet recording apparatus of the present invention.

FIG. 3 is an external perspective view of a multi-headed recording head shown in FIG. 1 of the present invention.

FIG. 4 is a schematic perspective view showing an example of the ink jet recording apparatus of the present invention.

FIG. 5 is a perspective view of an internal configuration showing an example of an ink cartridge.

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

[Explanation of symbols]

 13: Recording head 14: Ink groove 15: Heating head 16-1: Protective film 16-2: Top surface protective film 17-1, 17-2: Electrode 18: Heating resistor layer 19: Thermal storage layer 20: Substrate 21: Ink 22: ejection orifice (micropore) 23: meniscus 24: ink droplet 25: recording material 26: multi-groove 27: glass plate 28: heat generating head 40: ink bag 42: plug 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 unit 65: recording head 66: carriage 67: guide shaft 68: motor 69: belt 70: Recording unit 71: Head 72: Atmospheric communication port

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C056 EA21 FA03 FC01 HA17 2C057 AF65 AG46 AH20 BA05 BA13 2H086 BA53 BA55 BA62 4J039 AD02 AD03 AD06 AD09 AD10 AD14 AD22 AE01 AE07 BA04 BC07 BC09 BC13 BC19 BC33 BC35 BC50 BC51 BC55 BE01 BE01 BE05 BE06 BE08 BE12 CA03 CA06 EA15 EA16 EA17 EA19 EA41 EA42 EA44 GA24

Claims (48)

[Claims] 1. A colorant, (b) a liquid medium, and (c)
An inkjet ink comprising an ammonium salt of an acid having a methyl group or a methylene group and a carboxyl group. 2. The total content of at least one compound selected from ammonium salts of acids having a methyl group or methylene group and a carboxyl group in (c) is 0.005 to 20 with respect to the total amount of the ink. The ink for ink-jet recording according to claim 1, which is in a percentage by weight. 3. The ink-jet printer according to claim 1, wherein the ammonium salt of an acid having a methyl group or a methylene group and a carboxyl group of (c) does not substantially affect the color tone of the ink. For ink. 4. The acid according to claim 1, wherein the acid (c) having a methyl group or a methylene group and a carboxyl group is an acid having 10 or less carbon atoms and 3 to 6 oxygen atoms. Inkjet ink. 5. The method according to claim 1, wherein the acid having a methyl group or a methylene group and a carboxyl group of (c) is at least one selected from malonic acid, succinic acid, glutaric acid, adipic acid, lactic acid, malic acid, aspartic acid and glutamic acid. The inkjet ink according to any one of claims 1 to 4, which is a seed. 6. A colorant, (b) a liquid medium, and (d)
An inkjet ink comprising an ammonium aldonic acid salt. 7. The ink-jet ink according to claim 6, wherein at least one of the ammonium aldonic acid salts (d) is an ammonium gluconate salt. 8. A color material, (b) a liquid medium, and (e)
An ink-jet ink comprising at least one compound selected from monoammonium citrate, diammonium citrate and triammonium citrate. 9. The total content of at least one compound selected from the group consisting of monoammonium citrate, diammonium citrate and triammonium citrate of (e) is 0.005 to 20% by weight based on the total amount of the ink. The inkjet ink according to claim 8, which is% by mass. 10. The ink-jet ink according to claim 1, wherein the coloring material (a) is a water-soluble dye. 11. The method according to claim 1, wherein the color material (a) is a pigment.
10. The ink-jet ink according to any one of items 9 to 9. 12. The ink jet printer according to claim 1, wherein the liquid medium (b) contains water, and the content of water is 35 to 96% by weight based on the total amount of the ink. ink. 13. An ink jet having a recording head provided with a heater for applying thermal energy to ink to discharge the ink from an orifice, and a top protective layer containing metal and / or metal oxide for protecting the heater. An ink used in a recording apparatus, comprising: (a) a color material, (b) a liquid medium, and (c) at least one or more ammonium salts of an acid having a methyl group or a methylene group and a carboxyl group. Characteristic inkjet ink. 14. An ink jet apparatus comprising: a heater for applying thermal energy to ink to discharge the ink from an orifice; and a recording head having a top surface protective layer containing metal and / or metal oxide for protecting the heater. What is claimed is: 1. An ink-jet ink comprising: (a) a colorant; (b) a liquid medium; and (d) at least one ammonium aldonic acid salt. 15. An ink jet having a heater for applying thermal energy to ink to discharge the ink from an orifice, and a recording head provided with a top surface protection layer containing metal and / or metal oxide for protecting the heater. An ink used in a recording apparatus, comprising: (a) a coloring material, (b) a liquid medium, and (e) at least one or more selected from monoammonium citrate, diammonium citrate, and triammonium citrate. An inkjet ink comprising a compound. 16. The metal oxide according to claim 13, wherein the metal and / or the oxide of the metal is tantalum and / or an oxide of tantalum.
6. The inkjet ink according to any one of the items 5 to 5. 17. A method for reducing kogation on a heater surface in an ink jet recording apparatus provided with a recording head having a heater for applying thermal energy to ink to discharge the ink from an orifice,
6. A kogation to a heater, wherein the heater comprises an outermost protective layer containing a metal and / or a metal oxide, and wherein the ink according to any one of claims 1 to 5 is used as the ink. Adhesion reduction method. 18. The energy input to the heater for discharging ink is E _op, and the minimum energy input to the heater for discharging ink from the recording head is E _th , where E _op / The method according to claim 17, wherein E _th (= γ) satisfies the following relationship. 10 ≦ E _op / E _th ≦ 1.75 19. A method for reducing kogation adherence to a heater surface in an ink jet recording apparatus provided with a recording head having a heater for applying thermal energy to ink to discharge the ink from an orifice,
A method for reducing kogation on a heater, wherein the heater includes an outermost surface protective layer containing a metal and / or a metal oxide, and the ink according to claim 6 or 7 is used as the ink. 20. The energy supplied to the heater of the ink jet recording head unit for discharging ink is E _op, and the minimum energy input amount to the heater for discharging ink from the recording head is E _th. 20. The method according to claim 19, wherein the energy ratio E _op / E _th (= γ) satisfies the following relationship: 1.10 ≦ E _op / E _th ≦ 1.90 21. A method for reducing kogation on a heater surface in an ink jet recording apparatus provided with a recording head having a heater for applying thermal energy to ink to discharge the ink from an orifice,
A method for reducing kogation on a heater, wherein the heater includes an outermost surface protective layer containing a metal and / or a metal oxide, and the ink according to claim 8 or 9 is used as the ink. 22. When the energy input to the heater for discharging ink is E _op and the minimum energy input to the heater for discharging ink from the recording head is E _th , E _op / 22. The method according to claim 21, wherein E _th (= γ) satisfies the following relationship. 1.10 ≦ E _op / E _th ≦ 1.70 23. The method according to claim 17, wherein the coloring material (a) in the ink is a water-soluble dye. 24. The colorant (a) is a pigment.
23. The method for reducing kogation adhered to a heater according to any one of items 22 to 22. 25. The method according to claim 17, wherein the liquid medium (b) in the ink contains water, and the content of the water is 35 to 96% by weight based on the total amount of the ink. A method for reducing kogation on heaters. 26. The metal according to claim 17, wherein the metal and / or the metal oxide is tantalum and / or a tantalum oxide.
6. The method of reducing kogation adherence to a heater according to any one of the above items 5. 27. An ink jet recording method including a step of applying thermal energy to an ink to eject the ink from an orifice, wherein the ink according to claim 1 is used. 28. When the energy input to the heater for discharging ink is E _op and the minimum energy input to the heater for discharging ink from the recording head is E _th , E _op / The ink jet recording method according to claim 27, wherein E _th (= γ) satisfies the following relationship: 1.10 ≦ E _op / E _th ≦ 1.75 29. An ink-jet recording method including a step of applying thermal energy to ink and discharging the ink from an orifice, wherein the ink according to claim 6 or 7 is used. 30. When the energy input to the heater for discharging ink is E _op and the minimum energy input to the heater for discharging ink from the print head is E _th , E _op / _30. The ink jet recording method according to claim 29, wherein E _th (= γ) satisfies the following relationship. 1.10 ≦ E _op / E _th ≦ 1.90 31. An ink-jet recording method including a step of applying thermal energy to ink and discharging the ink from an orifice, wherein the ink according to claim 8 or 9 is used. 32. When the energy input to the heater for discharging ink is E _op and the minimum energy input to the heater for discharging ink from the recording head is E _th , E _op / The ink jet recording method according to claim 31, wherein E _th (= γ) satisfies the following relationship. 1.10 ≦ E _op / E _th ≦ 1.70 33. An ink jet recording method in which ink is ejected as ink droplets from an ink jet recording head by the action of thermal energy, in order to reduce kogation adhering on the heater, according to any one of claims 17 to 26. An ink jet recording method characterized by applying the method for reducing kogation on a heater according to (1). 34. An ink containing section containing ink,
An ink jet recording head having a heater for applying thermal energy to the ink in the ink flow path led from the ink storage section, and a means for applying a pulse-like electric signal to the heater in accordance with recording information. An ink jet recording apparatus, wherein the heater has a top surface protective layer containing a metal and / or a metal oxide, and the ink is the ink according to any one of claims 1 to 5. Characteristic inkjet recording device. 35. When the energy input to the heater for discharging ink is E _op and the minimum energy input to the heater for discharging ink from the recording head is E _th , E _op / The ink jet recording apparatus according to claim 34, wherein E _th (= γ) satisfies the following relationship. 1.10 ≦ E _op / E _th ≦ 1.75 36. An ink containing section containing ink.
An ink jet recording head having a heater for applying thermal energy to the ink in the ink flow path led from the ink storage section, and a means for applying a pulse-like electric signal to the heater in accordance with recording information. 8. An ink jet recording apparatus, wherein the heater includes an outermost surface protective layer containing a metal and / or a metal oxide, and the ink is the ink according to claim 6 or 7. apparatus. 37. When the energy input to the heater for discharging ink is E _op and the minimum energy input to the heater for discharging ink from the recording head is E _th , E _op / The ink jet recording apparatus according to claim 36, wherein E _th (= γ) satisfies the following relationship. 1.10 ≦ E _op / E _th ≦ 1.90 38. An ink containing section containing ink.
An ink jet recording head having a heater for applying thermal energy to the ink in the ink flow path led from the ink storage section, and a means for applying a pulse-like electric signal to the heater in accordance with recording information. 10. An ink jet recording apparatus, wherein the heater is provided with a top surface protective layer containing a metal and / or a metal oxide, and the ink is the ink according to claim 8 or 9. apparatus. 39. When the energy input to the heater for discharging ink is E _op and the minimum energy input to the heater for discharging ink from the recording head is E _th , E _op / 39. The ink jet recording apparatus according to claim 38, wherein E _th (= γ) satisfies the following relationship. 1.10 ≦ E _op / E _th ≦ 1.70 40. The metal according to claim 34, wherein the metal and / or metal oxide is tantalum and / or an oxide of tantalum.
The inkjet recording device according to any one of the above. 41. A method for extending the life of a recording head provided with a heater for applying thermal energy to an ink, which is used in an inkjet recording method including a step of applying thermal energy to the ink and discharging the ink from an orifice. ,
A long life service of a recording head, wherein the heater is provided with an outermost surface protective layer containing a metal and / or a metal oxide, and the ink according to any one of claims 1 to 5 is used as the ink. Method. 42. When the energy input to the heater for discharging ink is E _op and the minimum energy input to the heater for discharging ink from the recording head is E _th , E _op / The method for extending the life of a recording head according to claim 41, wherein E _th (= γ) satisfies the following relationship. 1.10 ≦ E _op / E _th ≦ 1.75 43. A method for extending the service life of a recording head provided with a heater for applying thermal energy to ink, which is used in an inkjet recording method including a step of applying thermal energy to ink and discharging the ink from an orifice, A method for extending the life of a recording head, comprising providing an outermost surface protective layer containing a metal and / or a metal oxide on the heater, and using the ink according to claim 6 or 7 as the ink. 44. When the energy input to the heater for discharging ink is E _op and the minimum energy input to the heater for discharging ink from the recording head is E _th , E _op / The method for extending the life of a recording head according to claim 43, wherein E _th (= γ) satisfies the following relationship. 1.10 ≦ E _op / E _th ≦ 1.90 45. A method for extending the life of a recording head provided with a heater for applying thermal energy to an ink, which is used in an inkjet recording method including a step of applying thermal energy to the ink and discharging the ink from an orifice, A method for extending the life of a recording head, comprising providing an outermost surface protective layer containing a metal and / or a metal oxide on the heater, and using the ink according to claim 8 or 9 as the ink. 46. When the energy input to the heater for discharging ink is E _op and the minimum energy input to the heater for discharging ink from the recording head is E _th , E _op / The method for extending the life of a recording head according to claim 45, wherein E _th (= γ) satisfies the following relationship. 1.10 ≦ E _op / E _th ≦ 1.70 47. A recording unit having an ink storage section containing ink and an ink jet recording head section for discharging the ink from an orifice by the action of thermal energy, wherein the ink jet recording head is The ink according to claim 1, further comprising a heater having a top surface protective layer containing a metal and / or a metal oxide for applying heat energy to the heater, wherein the ink is the ink according to claim 1. A recording unit, characterized in that: 48. The recording unit according to claim 47, wherein the metal and / or metal oxide is tantalum and an oxide of tantalum.