JP2003112469A - Ink jet recording method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet recording method, with which an ink excellent in light resistance and weatherability and having a high chroma and an unobtrusive granular feeling with the colored pigment ink. SOLUTION: In the ink jet recording method employing six kinds of pigment ink such as at least a black ink, a light cyan ink, a cyan ink, a light magenta ink, a magenta ink and a yellow ink, a pigment ink, in which a pigment having a small coloring power is employed, is printed afterwards onto a material to be recorded, into the outermost surface of which no pigment particle in the pigment ink substantially penetrates.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording method using an aqueous ink containing a fine particle organic pigment as a coloring material.

[0002]

2. Description of the Related Art Conventionally, dyes have been mainly used as a coloring material for ink jet inks, but in recent years, pigments have been used as a coloring material because images formed by dye inks have poor water resistance and light resistance. Ink examinations have become enthusiastic. In particular, the mounting of color pigment inks as an ink for wide format printers for industrial purposes such as posters, panels, signs, and pop advertisements has become an essential condition. The development of pigment ink aiming at entry into this field has led to the proposal of various pigment dispersion methods and manufacturing methods having inkjet suitability.

As a result, the problems of nozzle clogging in the head portion and long-term storage stability, which have been the immediate problems of ink jet pigment inks, have been considerably improved compared to the beginning. Regarding the color developability of images, with the aim of improving the color developability of color pigment inks, the development of optimization of the pigment particles used and the reduction of the particle size have progressed. It is now possible to obtain a color pigment ink having a color forming property almost equal to that of.

[0004]

However, there is a problem that the pigment ink can obtain a lower saturation than in the case of using the dye ink in the mixed color portion in which the respective color inks are superposed on the recording paper. . Even in the ink jet recording method using dye ink, various proposals have been made regarding various problems at the time of color mixing of ink on the paper surface. For example, JP-A-62-1615
Japanese Patent Laid-Open No. 41-41 proposes a method of operating the ink ejection order in a specific lightness order. However, although the above problems can be alleviated by recording in the order of low lightness, they have not been solved yet.

Therefore, an object of the present invention is to provide an ink jet recording method which is capable of forming an image using a color pigment ink, which is excellent in light resistance and weather resistance, has a high saturation even in a mixed color portion, and has a less grainy appearance. That is.

[0006]

DISCLOSURE OF THE INVENTION As a result of intensive studies, the present inventors have found that the above-mentioned object can be achieved by the present invention described below. That is, the present invention is an inkjet recording method using at least six types of pigment inks of black, light cyan, cyan, light magenta, magenta and yellow, and the pigment particles in the pigment ink are substantially present on the outermost surface of the recording material. (EN) Provided is an inkjet recording method, characterized in that a pigment ink using a pigment having a small coloring power is printed later on a recording material which does not enter.

In the present invention, the pigment of the black ink is carbon black, and the pigments of light cyan and cyan ink are C.I. I. Pigment Blue 15: 1, 1
5: 2, 15: 3 and 15: 4, and the pigments of light magenta and magenta ink are C.I. I. Pigment Red 122, and the pigment of the yellow ink is C.I.
I. Pigment Yellow 17, 93, 97, 98, 11
0, 128, 138, 139, 147, 150, 15
1, 154, 155, 180, and 185, and the ink is ejected to the recording material in the order of black ink, light cyan ink, cyan ink, light magenta ink, magenta ink, yellow ink, or black ink, cyan ink. And a light cyan ink, a magenta ink, a light magenta ink, and a yellow ink in this order.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will be described below. The reason why the problems of the prior art are solved by the inkjet recording method of the present invention is considered as follows. FIG. 1 shows a surface of a pigment ink printed on a recording material in which pigment particles in the pigment ink do not substantially enter the outermost surface of the recording material (the pigment ink manufactured by DICJET is packed in a Canon BJF8500 ink tank and printed). Thing) was observed by SEM. The pigment particles in the pigment ink mixed on the paper surface do not spread uniformly, and it can be seen that the pigment particles in the ink are piled up in the order in which they are driven.

As shown in FIG. 2, in ink jet recording using a pigment ink, when a pigment having a strong coloring power rides on a pigment having a weak coloring power, the color underneath is concealed, resulting in color mixing. It is difficult to get the desired color. This coloring power is possessed by the pigment particles and does not depend on the pigment concentration in the ink. On the other hand, the brightness of the ink is due to the concentration of the pigment. Therefore, it is preferable to record in the order of the coloring power of the pigment (the ink containing the pigment having the low coloring power is ejected later) instead of recording in the order of the lightness of the ink in order to obtain a better color mixture. The tinting strength of the pigment that characterizes the present invention is indicated by the numerical value of the weight of the white (titanium oxide) pigment with respect to 1 g of the tinting pigment required for making a light color.

The light color (θ = 6.0) is defined by the following equation. θ = 10− (1.2D / 9) S + 1.06D Where, θ: Value of color density D: Darkness according to DIN 6164 S: Saturation according to DIN 6164 According to this method, the coloring power of the pigment is determined regardless of the hue. Can be defined.

Next, the pigment ink used in the ink jet recording method of the present invention will be described. The pigment ink of the present invention is not particularly limited as long as it contains an organic pigment having a necessary color tone, but it is preferably composed of water, a pigment, a dispersant, an organic solvent, and other additives. is there.
The use ratio of each component of these inks may be the same as in the case of conventionally known pigment inks. Further, the pigment is preferably in the form of certain particles in order to obtain the light resistance and weather resistance of the image, and the particle diameter is controlled to be 20 nm or more and 200 nm or less to improve the coloring and dispersion stability of the pigment. It is preferable from the point.

In the present invention, ink jet recording is carried out using at least six types of pigment inks of black, light cyan, cyan, light magenta, magenta and yellow. Here, light cyan and light magenta are defined as inks having the same color but different in color density. Different pigments may be used for the dark ink and the light ink. As an example of the pigment that can be used as the pigment used in these inks, carbon black is preferably used as the pigment used in the black ink.

As the color pigment, there are C.I. I. Pigment Yellow 12, 13, 14, 17, 20, 24, 74,
83, 86, 93, 97, 109, 110, 117, 1
20, 125, 128, 137, 138, 147, 14
8, 150, 151, 153, 154, 166, 16
8, 180, 185, C.I. I. Pigment Orange 1
6, 36, 43, 51, 55, 59, 61, 71, C.I.
I. Pigment Red 9, 48, 49, 52, 53, 5
7, 97, 122, 123, 149, 168, 175,
176, 177, 180, 192, 215, 216, 2
17, 220, 223, 224, 226, 227, 22
8, 238, 240, 254, 255, 272, C.I.
I. Pigment Violet 19, 23, 29, 30,
37, 40, 50, C.I. I. Pigment Blue 15, 1
5: 1, 15: 3, 15: 4, 15: 6, 22, 60,
64, C.I. I. Pigment Green 7, 36, C.I. I.
Pigment Brown 23, 25, 26, etc. can be illustrated.

Among these, the effects of the present invention are more significantly exhibited in the case of black ink in the case of carbon black, and in the case of light cyan and cyan inks.
C. I. Pigment Blue 15: 1, 15: 2, 15:
3 and 15: 4, and the pigments of light magenta and magenta ink are C.I. I. Pigment Red 12
2 and the yellow ink pigment is C.I. I. Pigment Yellow 17, 93, 97, 98, 110, 128, 1
38, 139, 147, 150, 151, 154, 15
This is the case of any one of 5, 180 and 185.

The ink is ejected onto the recording material in the order of the ink containing a pigment having a high coloring power and the ink containing a pigment having a low coloring power. The recording material to be used may be any recording material as long as the pigment particles in the pigment ink do not substantially enter the outermost surface of the recording material. If it is absorbed below the outermost surface layer, the saturation is extremely reduced, which is not preferable. A preferable recording material for the present invention is one in which a porous layer containing boehmite or the like is provided on a base material, and the pore radius is 30
The pore volume of -100 nm is 0.5 cc / g or less, more preferably 0.3 cc / g or less. An inkjet recording apparatus suitable for recording using the ink used in the present invention may be any one as long as it can carry inks of 6 colors which are already on the market.

[0016]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples. Canon Inc. color printer B
The following inks can be used with JF8500 to Canon Inc. H
A natural image was printed on G201 paper (having a pore volume of 30 to 100 nm with a pore volume of 0.01 cc / g or less), and a natural image was printed to compare the color tones.

[0017]

<Example 1> Natural images were printed in the order of ink J, ink A, ink B, ink C, ink D, and ink E, and the color tones were compared. <Example 2> Natural images were printed in the order of ink J, ink F, ink G, ink H, ink I, and ink E, and the color tones were compared. <Example 3> A natural image was printed in the order of ink J, ink B, ink A, ink D, ink C, and ink E, and the color tones were compared.

<Comparative Example 1> Natural images were printed in the order of ink A, ink C, ink B, ink D, ink E, and ink J, and the color tones were compared. <Comparative Example 2> Natural images were printed in the order of Ink J, Ink E, Ink C, Ink A, Ink D, and Ink E, and the color tones were compared. Comparative Example 3 A natural image was printed in the order of ink A, ink B, ink C, ink D, ink E, and ink J, and the color tones were compared. The images printed in the embossing order of the example had a higher saturation of the mixed color portion of green and red than the comparative example, and there was no graininess, and the image was more natural.

[0020]

As described above, according to the present invention, in a full-color image using a pigment ink, an image having high saturation even in a mixed color portion and less graininess can be obtained. Further, the obtained image was excellent in light resistance and weather resistance.

[Brief description of drawings]

FIG. 1 is an SEM photograph of a surface of a recording material recorded with a pigment ink.

FIG. 2 is a diagram illustrating a state in which a pigment having a strong coloring power overlaps a pigment having a low coloring power.

Continued front page    F-term (reference) 2C056 EA04 EA11 EA13 EE10 FC02                 2H086 BA01 BA02 BA04 BA53 BA55                       BA62                 4J039 BE01 EA15 EA16 EA17 EA19                       EA21 EA34 EA35 GA24

Claims (2)

[Claims] 1. In an inkjet recording method using at least six types of pigment inks of black, light cyan, cyan, light magenta, magenta and yellow, the pigment particles in the pigment ink substantially enter the outermost surface of the recording material. An ink-jet recording method, characterized in that a pigment ink containing a pigment having a small coloring power is printed later on a non-recording material. 2. The black ink pigment is carbon black, and the light cyan and cyan ink pigments are C.I.
I. Pigment Blue 15: 1, 15: 2, 15: 3 and 15: 4, and the pigments of light magenta and magenta ink are C.I. I. Pigment Red 122, and the pigment of the yellow ink is C.I. I. Pigment Yellow 17, 93, 97, 98, 110, 128, 13
8, 139, 147, 150, 151, 154, 15
5, 180, and 185, and the order of ink ejection onto the recording material is black ink, light cyan ink, cyan ink, light magenta ink, magenta ink, yellow ink, or black ink, cyan ink, light cyan ink, The inkjet recording method according to claim 1, wherein the order is magenta ink, light magenta ink, and yellow ink.