JP2006088424A - Recording method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recording method suitable for an inkjet recording system, by which an image having high color developing properties can be obtained with favorable fixing properties though this recording method employs a pigment ink, resulting in obtaining an image, in which feathering is suppressed and which is excellent in scratch resistance and resistance to line marker. <P>SOLUTION: In the recording method for forming an image by giving a water-based ink including a pigment with an ionic functional group to a recording medium, the water-based ink includes a binder having an ionic functional group, the polarity of which is opposite to that of the pigment, and the recording medium has an ink accepting layer, which has an ionic component with the same polarity as that of the pigment or includes a metal hydroxide and/or metal oxide. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a recording method for forming an image on a recording medium having an ink receiving layer containing a specific component, using an aqueous ink having a pigment and a binder, to which an ink jet recording system can be suitably applied.

  In recent years, with the widespread use of personal computers, digital cameras, and the like, it has been required to display image information and the like created by these devices on recording paper with the same image quality as silver halide photography. Then, as means for printing on recording paper, an ink jet is used in which solution-like ink is ejected from a nozzle onto recording paper, which is a recording medium, using an electric field, heat, pressure, or the like as a drive source, and an image is formed with the ink. Recording methods are used.

  In the ink jet recording method, water-based ink is usually used, and as a recording paper, a recording paper having an ink receiving layer formed on a support is generally used for photographic applications such as image information. (See Patent Document 1). In addition, as a coloring material for the water-based ink, since a high-quality image is required for photographic use, a water-soluble dye having excellent fixability is generally used. A pigment having high image fastness is used (see Patent Document 2). Hereinafter, a water-based ink using a dye as a color material is referred to as a dye ink, and a water-based ink using a pigment as a color material is referred to as a pigment ink. Here, in the case of a dye, it is easily fixed because it is dyed (chemically bonded) to the cellulose constituting the recording paper. However, in the case of a pigment, since it does not usually dye, it remains as it is. Then, there exists a subject that it is inferior to fixing properties, such as abrasion resistance and line marker resistance.

  In the pigment ink, there are several methods for improving the performance related to the fixing property to a recording medium such as recording paper, but as described below, it is difficult to say that all are sufficient, and there is room for improvement. is there.

  For example, (1) Increasing the penetration of pigment ink into paper can reduce the amount of pigment on the paper surface and improve image fixability. However, the pigment penetrates into paper. Another problem arises that the color density is lowered and the feathering is inferior. Alternatively, (2) there is a method of improving the fixability by incorporating a substance that binds to the pigment into a recording medium such as recording paper, but in order to give sufficient fixing performance, a large amount of the substance is used. This is unrealistic because it is necessary and is too costly for applications such as plain paper. In addition, (3) there is a method of improving the fixability by including a resin component having a binding property with the pigment in the ink. However, in order to provide sufficient fixing performance, it is necessary to use a large amount of the component. In particular, when the ink jet recording method is used, the ink viscosity is increased, and therefore, the ink jet characteristics are inferior, which is not practical.

JP2003-251915A JP-A-5-171082

  For the reasons described above, the ink-jet recorded material has a color density, image fastness, fixing property, scratch resistance, line marker resistance, etc., compared with a printed material obtained by an electrophotographic method output from a laser printer. It is difficult to achieve both. In particular, it is difficult to obtain an ink-jet recorded product having both good color developability and fixability using pigment ink.

  Accordingly, an object of the present invention is to provide a recording method using a pigment ink, and a high color-developing image can be obtained with good fixability. Another object of the present invention is to provide a recording method applicable to an ink jet recording method, which has excellent line marker resistance (fixability).

  The above object is achieved by the present invention described below. That is, the present invention relates to a recording method for forming an image by applying an aqueous ink containing a pigment having an ionic functional group to a recording medium, wherein the aqueous ink has an ionic functional group having a polarity opposite to that of the pigment. And a recording medium having an ink receiving layer containing an ionic component having the same polarity as that of the pigment.

  The present invention also provides a recording method for forming an image by applying an aqueous ink containing a pigment having an ionic functional group to a recording medium, wherein the aqueous ink has an ionic functional group having a polarity opposite to that of the pigment. And a recording medium having an ink receiving layer containing a metal hydroxide and / or a metal oxide.

  The present invention also provides a recording method for forming an image by applying an aqueous ink containing a pigment having an ionic functional group to a recording medium, wherein the aqueous ink has an ionic functional group having a polarity opposite to that of the pigment. The recording medium has an ink-receiving layer containing an ionic component having the same polarity as the pigment, and a metal hydroxide and / or metal oxide.

  According to the present invention, since it is not necessary to give a very high performance to the binder contained in the ink or the ink receiving layer provided on the recording medium such as paper as in the prior art, the ink is stable. In addition, the color density of the printed image is high, and an image having excellent fastness (fixing property) such as scratch resistance and line marker resistance can be formed. Further, according to the present invention, both the binder contained in the ink and the specific ionic component contained in the ink receiving layer provided on the recording medium can be obtained in a small amount, so that a sufficient effect can be obtained. High practicality can be achieved with little increase in cost and change in characteristics. Furthermore, since the image formed by the recording method according to the present invention has saturation, resolution, and durability that can be comparable to an electrophotographic image, its industrial value is very high.

  The present invention will be described in more detail with reference to preferred embodiments of the present invention. First, the pigment used in the present invention only needs to have an ionic functional group, and may be any pigment that can be dispersed in water. Specific examples include anionic and cationic pigments that can be dispersed in water. In addition, since the binder contained in the ink has an ionic functional group, it is dissolved or dispersed in water, and the ionic functional group has a polarity opposite to that of the ionic functional group of the pigment. Maintains affinity with water and binds to pigments.

  In the present invention, by adding an ionic component having the same polarity as the pigment used in the ink to the ink receiving layer provided on the recording medium that imparts the ink having the above characteristics, the pigment and / or the binder, Since it binds to the base material forming the receptor layer, the obtained image has improved fixing performance such as scratch resistance, water resistance, and line marker resistance. The same effect can be obtained even if the ink receiving layer contains a metal oxide or metal hydroxide.

  Hereinafter, specific embodiments of the present invention will be described in more detail. Since the pigment used in the present invention is a pigment having an ionic functional group, the solubility or dispersibility in water is improved. Examples of the pigment having an anionic functional group include those having a sulfonic acid group, a carboxylic acid group, a phosphoric acid group, and the like. Specifically, Naphthol Yellow S, Pig. Yellow 100, 115, Pig. Orange 17: 1, Pig. Violet 16, Pig. Blue 17, 19 and Pig. Red 48: 2, 49: 1, 54, 64, 65, Pig. Black1, CAB-O-JET300, CAB-O-JET200 (manufactured by Cabot Corporation) and the like can be preferably exemplified.

  Examples of the pigment having a cationic functional group include pigments having onium ions such as quaternary ammonium ions, sulfonium ions and phosphonium ions, and pigments having quaternary nitrogen cations in the chemical structure. Specifically, Pig. Blue2, 9 and Pig. Red 81, Pig. Green4, Pig. Violet 1, 3 and the like can be preferably exemplified.

  The binder used in the ink used in the present invention needs to have an ionic functional group in order to dissolve or disperse in water. Specifically, a resin or oil / fat having an ionic functional group is used. it can. Examples of the binder having an anionic functional group include polyvinyl acetate, sodium polystyrene sulfonate, polylactic acid, polyphosphoric acid, polyacrylic acid, and polymethacrylic acid. A coalescence composition is mentioned.

  Examples of the binder having a cationic functional group include a cationic group in the resin, such as poly-4-vinylpyridine, poly-2-vinylpyridine, or an onium salt such as a quaternary ammonium salt at a side chain or terminal. The polymer composition etc. which have can be illustrated preferably.

  Next, a recording medium that is another feature of the present invention will be described. In the present invention, a recording medium having an ink receiving layer formed on the surface is used, but a recording medium having an ionic component having the same polarity as the pigment in the ink described above is used. In another embodiment, a recording medium in which an ink receiving layer containing a metal hydroxide and / or a metal oxide is formed is used. Furthermore, as a preferred form, a recording medium is used in which an ink receiving layer containing an ionic component having the same polarity as the pigment in the ink and a metal hydroxide and / or metal oxide is formed.

  Preferred examples of the ionic component contained in the ink receiving layer include the same binders used in the ink as described above, and chitin and chitosan. Further, the amount used is preferably about 0.1 to 30% by mass, more preferably 1 to 10% by mass in the coating liquid for forming the ink receiving layer. If the application amount of the ionic component in the ink receiving layer is more than the above range, the paper that is the base material forming the ink receiving layer may be hydrolyzed. On the other hand, when the content is less than 0.1% by mass, it is difficult to obtain a clear effect by forming the ink receiving layer on plain paper or the like.

  Preferred examples of the metal oxide to be contained in the ink receiving layer include magnesium oxide, zinc oxide, calcium oxide, titanium oxide, zirconia, and alumina. Moreover, preferable examples of the metal hydroxide include aluminum hydroxide, magnesium hydroxide, and zinc hydroxide. The amount of these used is preferably 3 to 40% by mass, and particularly preferably 5 to 20% by mass in the coating liquid for forming the ink receiving layer. That is, when the amount is less than 3% by mass, it is difficult to obtain a clear effect by forming the ink receiving layer on plain paper or the like. On the other hand, if the amount used is more than the above range, problems such as increased brittleness of paper as a base material for forming the ink receiving layer occur.

  The pigments and binders described above that are contained in the ink used in the present invention can be suitably used as components of the ink. In addition, the ionic component, metal oxide, and metal hydroxide having the above-described configuration, which are contained in the ink receiving layer of the recording medium used in the present invention, are preferably used as components of the ink receiving layer. It is something that can be done. The recording method according to the present invention can obtain the higher effect as described above by combining the ink having the above-described configuration and the ink receiving layer. The recording method according to the present invention is particularly suitable for recording by an ink jet recording method.

  The content of the pigment in the ink used in the present invention is preferably about 0.5 to 25% by mass, more preferably about 1 to 15% by mass in the ink. In addition, the amount of the binder in the ink used in the present invention is preferably about 0.1 to 25% by mass, more preferably about 0.2 to 5% by mass. The total content of ionic components, metal oxides, and metal hydroxides contained in the ink receiving layer of the recording medium used in the present invention is set to 0. 0 in the coating liquid used to form the ink receiving layer. It is preferable to set it as about 1-40 mass%, More preferably, it is about 0.5-30 mass%.

  The ink used in the present invention comprises the above-described components and water, but may further contain a water-soluble organic solvent as described below as a wetting agent. Specific examples of the wetting agent include, for example, oxyethylene or oxypropylene copolymers such as diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, polyethylene glycol, and polypropylene glycol; ethylene glycol, propylene glycol, triethylene glycol, Alkylene glycols having 2 to 6 carbon atoms in alkylene groups such as methylene glycol, triethylene glycol, 1,2,6-hexanetriol; glycerin; ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, etc. Lower alkyl ethers; triethylene glycol dimethyl ether, tetraethylene glycol diethyl ether Lower dialkyl ethers of polyhydric alcohols such as ter; alkanolamines such as monoethanolamine, diethanolamine, triethanolamine; sulfolane, N-methyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazo Examples include lysinone. The water-soluble organic solvents as described above can be used alone or as a mixture. The addition amount of these wetting agents is preferably 0.1 to 30% by mass, more preferably 1 to 10% by mass with respect to the ink.

  The surface tension of the ink used in the present invention comprising the above components is preferably 30 to 45 mN / m, more preferably 35 to 40 mN / m. When the surface tension is 30 mN / m or more, there is no possibility that the penetration speed in the recording medium is too high, and the fixing mechanism by the binder having an ionic functional group works favorably, and the ink receiving layer provided on the surface of the recording medium The pigment can be fixed in a good state. In addition, if the surface tension of the ink is suppressed to 45 mN / m or less, the ink permeates into the recording medium and the pigment adhered to the surface of the recording medium decreases, so that the marker resistance of the image decreases. Can be avoided. The surface tension of the ink can be appropriately adjusted depending on the amount of the surfactant added to the ink.

  Examples of the surfactant that can be suitably used in the above are not particularly limited as long as they do not adversely affect the storage stability of the ink when added to the ink. For example, fatty acid salts Anionic surfactants such as higher alcohol sulfates, liquid fatty oil sulfates, alkylallyl sulfonates, polyoxyethylene alkyl ethers, polyoxyethylene alkyl esters, polyoxyethylene sorbitan alkyl esters, acetylene Nonionic surfactants such as alcohol and acetylene glycol are listed. These may be used alone or in appropriate combination of two or more. The content when these surfactants are added to the ink is preferably 0.01 to 5.0% by mass, more preferably 0.1 to 0.3% by mass, based on the total amount of the aqueous pigment ink. A range is desirable.

  Hereinafter, the present invention will be described in more detail with reference to experimental results of preferred embodiments to which the present invention is applied. For the pigment and binder constituting the ink used in the examples, anionic carbon black (sulfonic acid sodium salt) is used for the pigment, and for the binder, a polyvinyl alcohol having a reverse polarity and a cationic property (polyethylene) Oxyethylene-quaternary ammonium salt) was used. The surfactant added to the ink is an acetylene glycol ethylene oxide adduct.

[Example 1]
(Preparation of ink BK-1)
In this example, ink having the following composition was used.
・ Carbon black dispersion (manufactured by Cabot,
Product name: CAB-O-JET300) 35g
・ Binder (Kuraray Co., Ltd., trade name: C-506)
0.5g
・ Water 29.36g
・ Surfactant (made by Kawaken Fine Chemicals,
Product name: Acetylenol EH) 0.14g
・ Glycerin (wetting agent) 20g
・ Ethylene glycol (wetting agent) 15g

  The above-mentioned components were put in a sample bottle, and then stirred and mixed using a magnetic stirrer to prepare a pigment black ink (ink BK-1) used in this example. When the surface tension of the ink BK-1 thus obtained was measured with a surface tension meter (Kyowa Interface Science Co., Ltd., CBVP-A3), the surface tension of the ink BK-1 was 37.0 mN / m. Met.

(Preparation of recording medium)
<Preparation of coating liquid A>
First, a prepared solution having the composition shown below is placed in a mayonnaise bottle (volume: 100 ml), zirconia beads (specific gravity: 6.0 g / cm ³ , φ: 0.5 mm) are added and sealed, and a paint shaker (Toyo Seiki) The coating solution A was prepared by shaking for 15 hours.
・ Magnesium hydroxide (Kanto Chemical Co., Inc .: reagent deer grade 1)
3.3g
・ Nonionic dispersion resin (Daiichi Kogyo Seiyaku Co., Ltd., trade name:
Epan 785) 0.33g
・ Deionized water 29.37g

<Preparation of coating liquid B>
A coating solution B was prepared in the same manner as in the coating solution A except that magnesium hydroxide was replaced with zinc oxide (manufactured by Kanto Chemical Co., Inc .: reagent grade).

<Preparation of coating liquid C>
A preparation liquid having the composition shown below was placed in a mayonnaise bottle and stirred and mixed with a magnetic stirrer to prepare a coating liquid C in the same manner as the coating liquid A.
・ Polyacrylic acid (Wako Pure Chemical Industries, trade name: 25% polyacrylic acid solution) 25 g
・ 75 g of deionized water

<Preparation of coating liquid D>
The coating liquid B and the coating liquid C obtained as described above were mixed at a ratio of 1: 1 to prepare a coating liquid D.

<Formation of ink receiving layer>
Using each of the coating liquids A, B, C, and D prepared above, using plain paper (Canon: PB paper) as a base material, a bar coat (bar coater: No. 8) is formed thereon, An ink receiving layer was formed. And what was obtained was used as evaluation paper A, B, C, and D.

[Evaluation]
The ink BK-1 prepared as described above is mounted on an ink jet printer machine (manufactured by Canon Inc .: BJ S700), and ink jet recording is performed on the evaluation papers A to D obtained above using the ink BK-1, and evaluation printed materials 1 to 4 Got. Each printed portion was evaluated by the following method and criteria, and the results are shown in Table 1.

<Optical density>
The optical density (OD) of the solid print part was measured by the reflection method (X-Rite Inc., 310) for the print part of each evaluation printed matter 1 to 4 one hour after printing. And it evaluated on the following references | standards.
○: OD> 1.4
Δ: 1.4 ≧ OD> 1.3
×: 1.3 ≧ OD

<Feathering>
About each evaluation printed matter 1-4, the printed part 10 minutes after printing was observed with the microscope, and the following references | standards evaluated.
○: No feathering △: Slightly seen ×: Many feathering seen

<Line marker resistance>
About each evaluation printed matter 1-4, the printing part 10 minutes after printing was marked from the left side 1 cm away from the solid printing part to the right side 1 cm away using the highlighter pen (product name: Spotter). . The difference in optical density (ΔOD) on both sides was measured, and the marker resistance was evaluated according to the following criteria.
×: ΔOD ≧ 0.05
Δ: 0.02 <ΔOD <0.05
○: 0.01 <ΔOD ≦ 0.02
A: ΔOD ≦ 0.01

<Abrasion resistance>
About each evaluation printed matter 1-4, the printing part 10 minutes after printing printed the sillbon paper 10 times under a 200-g load, visually observed the edge periphery of the solid printing part, and evaluated it on the following references | standards.
○: No rubbing trace is seen. Δ: Some rubbing trace is seen. ×: Many rubbing traces are seen.

[Comparative Example 1]
Using the same ink BK-1 and recording apparatus as used in Example 1, inkjet recording was performed on plain paper (Canon: PB paper) having no ink receiving layer, and an evaluation printed matter 5 was obtained. It was. The printed portion of the evaluation printed matter 5 was evaluated in the same manner as the evaluation printed matter 1 to 4 in Example 1, and the results are shown in Table 1.

[Comparative Example 2]
An ink was prepared in the same manner as in the composition of the ink BK-1 used in Example 1, except that the added binder was excluded and the total amount was 100 g with water, and a pigment black ink composition (ink BK) was prepared. -2) was prepared. The surface tension of the ink BK-2 was measured and found to be 39.6 mN / m. Next, using the obtained ink BK-2, the same evaluation papers A, B, C, and D as used in Example 1, and the plain paper used in Comparative Example 1, respectively, Inkjet recording was performed with the same apparatus as used, and evaluation printed materials 6 to 10 were obtained. Evaluations similar to those performed in Example 1 were performed on the printed portions of the obtained evaluation printed materials 6 to 10. The results obtained are summarized in Table 1.

[Reference Example 1]
Electrophotographic recording was performed using a laser beam printer (trade name: LBP-1810, manufactured by Canon Inc.) to obtain an evaluation printed matter 11. Evaluation similar to that performed in the example was performed on the printed portion. The obtained results are shown in Table 1.

  As shown in Table 1, the evaluation printed materials 1 to 4 of Example 1 exhibited higher characteristics in terms of fixing performance (marker resistance and scratch resistance) and suppression of feathering compared to the comparative examples. . In particular, it was found that the evaluation printed materials 3 and 4 achieve particularly excellent optical density, fixing performance, and image quality. On the other hand, in Comparative Example 1, since the printing was performed on plain paper having no ink receiving layer, the fixing performance was particularly insufficient. In addition, in the ink BK-2 which does not contain a binder used in Comparative Example 2, by using a paper having an ink receiving layer, the image formed is more resistant to line markers than when printed on plain paper. Although an improvement in scratch resistance was observed, sufficient fixing performance was not obtained as compared with the examples. Furthermore, according to Example 1, it was confirmed that even when compared with the electrophotographic printed matter shown in Reference Example 1, it was possible to achieve line marker resistance and scratch resistance at the same level.

  From the above results, it was found that according to the present invention, the obtained recorded image has a high color density, does not cause feathering, and has excellent scratch resistance and line marker resistance.

  As an application example of the present invention, in the configuration of the present invention, since it is not necessary to give a remarkably high performance to the binder contained in the ink or the ink receiving layer provided on the paper, it is also stable as an ink for ink jet recording. In addition, the obtained print image has a high color density, high quality, and excellent fixing properties such as scratch resistance and line marker resistance, and an excellent recording method suitable for an ink jet recording system is provided. . In addition, since the ink used in the configuration of the present invention and the ink receiving layer of the recording medium can be prepared with a small amount of binder added, there is no significant cost increase due to improvement of these, and practical use. A recording method can be provided. Furthermore, there is provided a recording method with a very high industrial value that can provide an excellent image having saturation, resolution, and durability comparable to an image obtained by electrophotography.

Claims (7)

  In a recording method for forming an image by applying an aqueous ink containing a pigment having an ionic functional group to a recording medium, the aqueous ink contains a binder having an ionic functional group having a polarity opposite to that of the pigment, The recording method, wherein the recording medium has an ink receiving layer containing an ionic component having the same polarity as the pigment.   The recording method according to claim 1, wherein the ink receiving layer is formed using a coating liquid containing 0.1 to 30% by mass of an ionic component having the same polarity as the pigment.   In a recording method for forming an image by applying an aqueous ink containing a pigment having an ionic functional group to a recording medium, the aqueous ink contains a binder having an ionic functional group having a polarity opposite to that of the pigment, A recording method, wherein the recording medium has an ink receiving layer containing a metal hydroxide and / or a metal oxide.   The ink receiving layer was formed using a metal hydroxide containing any metal selected from Mg, Zn, Zr, Ti and Al and / or a coating liquid containing 3 to 40% by mass of a metal oxide. The recording method according to claim 3, wherein the recording method is a recording method.   In a recording method for forming an image by applying an aqueous ink containing a pigment having an ionic functional group to a recording medium, the aqueous ink contains a binder having an ionic functional group having a polarity opposite to that of the pigment, The recording method, wherein the recording medium has an ink receiving layer containing an ionic component having the same polarity as the pigment, and a metal hydroxide and / or a metal oxide.   A metal hydroxide and / or metal containing 0.1 to 30% by mass of an ionic component having the same polarity as the pigment and any metal selected from Mg, Zn, Zr, Ti and Al in the ink receiving layer The recording method according to claim 5, wherein the recording method is formed using a coating liquid containing 3 to 40% by mass of an oxide. The recording method according to claim 1, wherein the image is formed by an ink jet recording method.