JPS6358106B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an inkjet color printing system, and more particularly to an inkjet color printing system that provides color images with excellent color reproducibility and high water resistance. A color inkjet printing device that records multicolor images uses blue, green, and red density signals obtained by scanning each part of a color original image to print yellow, green, and red images.
The magenta and cyan inkjet ejection heads are driven, and the ejection amounts of each ink are adjusted to record a color image in a dot pattern. However, conventional color inkjet printing devices have not been able to record color images with hues that are faithful to the original image. When we investigated the causes of this poor color reproducibility, we found that color correction by masking processing was insufficient and that the combination of yellow, cyan, and magenta inks was inappropriate. In other words, conventional masking processing uses linear masking processing using three color density signals as variables, but extremely high-order nonlinearity exists between ink amount and optical density. Because of this existence, linear masking processing cannot perform sufficient color correction. In addition, the ink normally used in color inkjet printing equipment is disclosed in Japanese Patent Application Laid-Open No. 49-89534,
Special Publication No. 54-16243, Special Publication No. 16244, Special Publication No. 16243, Special Publication No. 16243, Special Publication No. 16243
No. 54-16245, JP-A-52-96105, JP-A-52-
No. 146307, JP-A-53-77706, JP-A-54-21765
Inks containing direct dyes or acid dyes such as those described in Japanese Patent Publication No. 54-89811, etc., however, when inks using these water-soluble dyes are mixed in subtractive color, there is a difference between the mixing ratio and hue. In addition to having nonlinearity, the combination tends to have coloring defects that cannot be absorbed even when polynomial masking processing including a nonlinear term described below is performed. Therefore, in order to improve color reproducibility, it is necessary to use ink with excellent color development and to perform masking processing that also takes into account the characteristics of this ink. On the other hand, in the field of inkjet recording,
High-quality paper, continuous slip paper, art paper, coated paper, paper made to low density without adding sizing agents, JP-A-52
―No. 53012, JP-A No. 52-74340, JP-A-53-
Inkjet recording paper with relatively good ink absorption and less spread of ink, as described in No. 49113, cloth, plastic film with an ink-absorbing surface, wooden boards, metal plates, etc., can be used as recording media. Are known. Among these, paper is the most typical recording medium. However, when inkjet recordings are made on these recording papers using water-based inks, the dye recordings bleed or disappear when exposed to water.
Almost no water resistance. Furthermore, if stored for a long period of time in a high humidity condition, inkjet recordings may smear. In particular, in the case of multicolor inkjet recording, since a large amount of ink is ejected, sufficient water resistance cannot be obtained even if the recording paper contains a dye-dyeable component. Particularly when inkjet recording paper is to be displayed outdoors, strong water resistance is required, and conventional inkjet recording paper has been impractical. Furthermore, when a commercially available mordant such as a dicyandimide condensate, polyamine, or polyethyleneimine is incorporated into an inkjet recording paper, the water resistance of an inkjet recorded image is improved to some extent. However, because the mordant does not have a strong mordant power and the mordant itself has high water solubility, a high degree of water resistance cannot be obtained. If there is even a slight elution of dye in an inkjet recorded image recorded with water-based ink, especially a half-tone multicolor inkjet recorded image, the image will bleed when exposed to water, resulting in an extremely poor image quality. That is, with conventionally known mordants,
It was not possible to completely prevent dye elution, and it was not possible to make inkjet recording paper waterproof. Furthermore, in the case of multicolor inkjet recording, ink is ejected from two or more nozzles, and one area on the paper is
Often more than one dot overlaps at a point, and even four colors of ink dots overlap at the same location. If the ink droplets are not quickly absorbed into the paper layer, the ink will overlap with the next ink droplet ejected at the same point on the paper, flow out, or scatter, staining the white background area. Furthermore, the paper surface may be rubbed and stained due to handling after recording.
Therefore, for multicolor recording, a recording paper with particularly good ink absorption is required. However, in a recording paper having good ink absorption properties, ink dots generally not only spread laterally but also have large penetration in the thickness direction. For example, paper that is made as bulky as possible without the addition of sizing agents has very good ink absorption and has enough ink absorption to withstand multicolor inkjet recording, but the lateral spread of the ink dots is large and the resolution is poor. In addition, the ink penetrates deeply into the thickness of the paper, and light is scattered by the gaps in the paper, resulting in a low density and whitish color, making it impossible to obtain a clear image. Also, when recording on paper with good ink absorption properties using four colors of ink: cyan, magenta, yellow, and black, the ink that was jetted first penetrates deep into the paper layer, causing the color to change from above. It becomes difficult to see and the color reproducibility becomes poor. In order to obtain images with good density, resolution, and color reproducibility using multicolor inkjet recording, it is necessary to make sure that the coloring components in the ink have a small lateral spread on the recording paper used, and that the coloring components in the ink are thick. These contradictory properties are required: less permeation in the horizontal direction, the presence of coloring components on the surface of the paper layer as much as possible, and good ink absorption. In order to solve this problem, several proposals have been made in the past. For example, JP-A-52-
No. 53012 discloses an inkjet recording paper made by coating a low-size base paper with a paint and allowing the paint to penetrate into the paper layer. Also, Unexamined Japanese Patent Publication No. 1973-
No. 49113 discloses an inkjet recording paper in which paper to which fine urea-formalin resin powder is added is impregnated with a water-soluble polymer. Furthermore, Japanese Patent Publication No. 1973-
No. 74340 discloses an inkjet recording paper having a specific air permeability and ink absorption time. However, the technical ideas found in these inkjet recording papers all aim to improve resolution, density, etc. at the expense of ink absorption, and although resolution and density are improved to some extent as a result, However, the ink absorbency was reduced, and the paper was unsatisfactory as a multicolor inkjet recording paper. SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an inkjet color printing system that reproduces hues faithful to the original image and provides color images with a high degree of water resistance. The present invention uses a color inkjet printing device using digital processing technology, performs non-linear masking processing, and uses yellow, magenta, and cyan inks with good color development, as described below, as well as a recording sheet to faithfully reproduce the original image. It is designed to record color images that have a bright hue and are highly water resistant. The present invention will be explained in detail below. In FIG. 1, a color inkjet printing apparatus embodying the present invention is comprised of a digital color scanner 1, an image information processing apparatus 2, and a printer 3. The digital color scanner 1 includes a rotating cylinder 1
Each part of the color original picture 11 wrapped around the paper is scanned to measure the density values of blue, green, and red. This rotating cylinder 10 is driven by a main scanning pulse motor 12, and is driven by a main scanning pulse motor 12.
The driving pulses applied to the rotating cylinder 10 are counted by a main scanning counter 13, and the position of the rotating cylinder 10 in the main scanning direction is detected. Note that this main scanning counter 1
3 is reset each time a certain reference position on the outer periphery of the rotating cylinder 10 passes a specific position. Therefore, the positions until the rotating cylinder 10 makes one revolution are counted. Illumination light emitted from the illumination light source 14 is condensed by a lens 15 and illuminates one point on the color original image 11 in the form of a spot. The light reflected by this color original image 11 passes through the lens 16 and passes through the half mirror 1.
7, and the optical path is divided into two by transmission and reflection. The light reflected by the half mirror 17 passes through the blue filter 18 and enters the blue light receiver 19, where it is photoelectrically converted. Further, the light transmitted through the half mirror 17 enters the half mirror 20, where the optical path is again divided into two. The light reflected by this half mirror 20 passes through a green filter 21 and enters a green light receiver 22 . On the other hand, the light transmitted through the half mirror 20 passes through the red filter 23 and enters the red light receiver 24 . These receivers 19, 2
2 and 24 measure the three color light components of each point of the color image. As the blue, green, and red filters 18, 21, and 23 used in the three-color separation photometry, those having spectral sensitivity characteristics of a CIE color matching function or a linear combination thereof, or spectral sensitivity characteristics similar thereto are used. is desirable. FIG. 2 shows an example of approximating the spectral sensitivity characteristics of CIE color matching functions. That is,
Considering the various colors recorded in a color original image, even if the colors are the same to the human eye, the spectral characteristics of the colors may vary widely. Therefore, it can be said that it is better to perform photometry using a system having spectral sensitivity characteristics suitable for the human eye. Such spectral sensitivity characteristics are generally referred to as "satisfying the router condition." In FIG. 2, the solid line is the practical characteristic illustrated in the present invention, but ideally the spectral sensitivity characteristic shown by the broken line is called a color matching function. The illumination light source 14, lenses 15, 16, half mirrors 17, 20, filters 18, 21, 23,
The light receivers 19, 22, and 24 are mounted on a moving table 25. This moving table 25 is
It moves parallel to the axial direction of the rotating cylinder 10 by the feed screw shaft 26 and the guide 27. This feed screw shaft 26 is driven by a sub-scanning pulse motor 28, and the drive pulses input to this sub-scanning pulse motor 28 are counted by a sub-scanning counter 29. The three color signals measured by the light receivers 19, 22, and 24 are each logarithmically converted by a logarithmic converter 30 provided for each color, and converted into a density signal.
These three color density signals are converted into digital signals by an AD converter 31. In this digital color scanner 1, each time the rotating cylinder 10 rotates once, the moving table 25 moves by one scanning line in the axial direction of the rotating cylinder 10, and scans each part of the color original image 11 two-dimensionally. . Through this scanning, the blue, green, and red reflection densities of each part of the color original image 11 are measured and converted into digital signals by the AD converter 31. Note that it is preferable to perform processing such as removing noise components or emphasizing the outline of the image before performing A/D conversion as necessary. Further, in this embodiment, the reflected light of the color original image 11 is measured, but for a color original image with high transmittance such as a color film, the rotating cylinder 10 is made transparent and the illumination light source 14 is installed inside it. The transmitted light of the color original image 11 may be measured using a scanner having a housed structure. The image information processing device 2 has an interface 3
3, a central processing unit 34, a storage device 35, a line buffer memory section 36, a UCR section 37, a table memory section 38, and a head drive section 39. A commonly used minicomputer is used as the central processing unit 34, which controls the digital color scanner 1 and printer 3, controls writing and reading of three color density signals (image information), and performs color correction. Performs image processing (additions/changes) such as masking processing and text insertion. When writing image information, the central processing unit 3
The drive pulse from 4 is input to the main scanning pulse motor 12 to rotate the rotating cylinder 10 in the main scanning direction. Each time the rotating cylinder 10 rotates once, the sub-scanning pulse motor 28 rotates by a certain angle. Therefore, the color original image 11 is scanned two-dimensionally, and each pixel on the scanning line is subjected to three-color separation photometry.
The obtained three-color density signals of blue, green, and red are converted into digital signals and taken into the central processing unit 34 via the interface 33. The captured three color density signals are sent to the main scanning counter 1.
3 and the position signal from the sub-scanning counter 29, an address corresponding to the pixel position is designated, and three color density signals are stored in the designated memory cell. The central processing unit 34 performs a masking process using a polynomial including a nonlinear term when writing or reading the three-color density signal, and performs color correction so that hues faithful to the color original image 11 are reproduced. Let's do it. This nonlinear masking is determined by taking photometric characteristics and ink characteristics into consideration, and a quadratic term, a logarithmic term, an exponential function term, etc. are used as the nonlinear term. As this non-linear masking, for example, a matrix of the following equation with three color density signals as variables is used.

【table】

[Yellow dye]

[Magenta dye] [Cyan dye] In each ink used in the present invention, the water-soluble dye is usually contained in an amount of 0.5 to 4% by weight per 100 parts by weight of the ink. If it is less than 0.5 parts by weight, it lacks the ability as a coloring agent, and if it is more than 4 parts by weight, even if the dye is in a dissolved state, precipitation will occur over a long period of time, making it unsuitable as a jet printing ink. . It is desirable to add a wetting agent to the aqueous ink used in the present invention for the purpose of improving the drying resistance of the ink and acting as a dye solubilizing agent. As a wetting agent, it is almost nonvolatile at room temperature, and the surface tension of a 3 to 40% aqueous solution at room temperature is 30 dyne/cm or more.
45dyne/cm or more, the solution viscosity is 5cps or less, and the water-soluble dye is 1% by weight at room temperature.
It is preferable to use a substance that dissolves in the above amount. Such wetting agents are disclosed in Japanese Patent Application Laid-open Nos. 50-71423 and 51.
-Described in No. 5127, No. 51-137505, etc.2
-Pyrrolidones; JP-A-49-97620, JP-A-51-8031, JP-A-51-
Carboxylic acid amide derivatives described in JP-A No. 8033; Lactones described in JP-A-55-48267; Dioxyethylene sulfur compounds described in JP-A-51-5129; JP-A-Sho 51- Alcohol amines described in JP-A No. 52004; N-formyl-lactam derivatives described in JP-A-51-31525; JP-A-51-40484, JP-A-51-137506,
Polyalkylene glycols and monoethers of polyalkylene glycol described in No. 54-12909; Monohydric alcohols such as t-butyl alcohol and n-amyl alcohol described in JP-A-51-129310; Cellulose derivatives such as hydroxypropyl cellulose and povinyl alcohol described in JP-A-50-17840; polyoxyethylene sorbitan fatty acid ester, polyoxyethylene fatty acid ester, and polyoxyethylene sorbitan fatty acid ester described in JP-A-50-143602; oxyethylene alkyl phenyl ether, etc.; water-soluble alginate described in JP-A-54-62005; and 1,3-dialkyl-2-imidazolidinone such as 1,3-dimethyl-2-imidazolidinone etc. are preferred. The amount of wetting agent used in the present invention varies depending on the type of wetting agent, but is usually preferably 0.2 to 30% by weight based on 100 parts by weight of the ink. In the aqueous ink used in the present invention, two or more of the above wetting agents may be used in combination. In the present invention, a black dye can be used in combination with the yellow, magenta and cyan dyes represented by the general formulas (), () and (). As a black dye, JP-A-50-15622, JP-A No. 50-
No. 17840, No. 50-49004, No. 51-5127, No. 51-
No. 5128, No. 51-52004, No. 51-137506, No. 53
Direct dyes and acid dyes described in No. 61412, No. 53-77706, and Japanese Patent Publication No. 54-16243 are effective. Antifungal agents and oxygen absorbers can also be added to the ink used in the present invention. Examples of antifungal agents include sodium dehydroacetate, which is described in JP-A-52-12008; 1,2-, which is described in JP-A-52-12009;
Benzisothizarin-3-one; 6-acetoxy-2,4-dimethyl-m described in JP-A-52-12010 and JP-A-52-96105
-Dioxane; Formalin and sodium pentachlorophenol as described in JP-A-50-15622; Sodium benzoate as described in JP-A-51-30019; As described in JP-A-53-135707 8-quinolinol citrate and the like are effective. As oxygen absorbers, JP-A-52-74406 and JP-A-53
- Sodium sulfite as described in No. 61412,
Sulfites such as sodium bisulfite are effective. Furthermore, the aqueous ink used in the present invention contains anionic surfactants (e.g. sodium alkyl sulfate, etc.), cationic surfactants (e.g. alkylpyridium sulfate, etc.), nonionic surfactants as surface tension adjusting agents. Agents (such as polyoxyethylene alkyl ethers) or amphoteric surfactants may also be used. According to the present invention, the yellow, magenta,
The water resistance of color images is greatly improved by using a sheet with a basic terrax polymer as a recording medium in combination with a cyan water-based ink. The basic latex polymer used in the present invention has a unit represented by the following general formula [XI]. General formula [XI] (-A)- _x (-B)- _y (-C)- _z In the formula, (A) is a copolymerizable monomer having a tertiary amino group or a quaternary ammonium group. Represents polymerized monomer units. (B) represents a monomer unit copolymerized with a copolymerizable monomer containing at least two ethylenically unsaturated groups. (C) is
Represents a monomer unit copolymerized with copolymerizable ethylenically unsaturated monomers other than (A) and (B). x is 10
y is 0 to 10 mol%, and z is 0 to 90 mol%. Preferred basic latex polymers used in the present invention are described below. In the general formula [XI], the monomer unit of (A) is preferably represented by the following general formula [XII], [] or []. General formula [XII] General formula [] General formula [] In the general formula [XII], R ₁₁ represents a hydrogen atom or a lower alkyl group having 1 to 6 carbon atoms (eg, methyl group, ethyl group, n-hexyl group, etc.). R ₁₂ , R ₁₃ and R ₁₄ each represent the same or different alkyl group having 1 to 6 carbon atoms or _an aralkyl group having ₇ to ₁₀ carbon atoms; They may be interconnected to form a cyclic structure together with nitrogen atoms. Substituted alkyl groups and substituted aralkyl groups are included in these alkyl groups and aralkyl groups.
Examples of alkyl groups include methyl group, ethyl group,
n-propyl group, n-hexyl group, etc.; Substituted alkyl groups include, for example, hydroxyalkyl groups (for example, 2-hydroxyethyl group, 3-hydroxypropyl group, 3-chloro-2-hydroxypropyl group, etc.), alkoxyalkyl groups ( For example, methoxymethyl group, 2-methoxyethyl group, etc.), cyanoalkyl group (for example, 2-cyanoethyl group, etc.),
Examples include halogenated alkyl groups (for example, 2-chloroethyl group), allyl groups, 2-butenyl groups, and propargyl groups. Examples of aralkyl groups include benzyl, phenethyl, and diphenylmethyl groups; examples of substituted aralkyl groups include alkylaralkyl groups (e.g., 4-methylbenzyl, 2,5-dimethylbenzyl, etc.), alkoxyaralkyl groups (e.g., 4-methoxy benzyl group, etc.), cyanoaralkyl group (eg, 4-cyanobenzyl group, etc.), halogenated aralkyl group (eg, 4-chlorobenzyl group, etc.), and the like. An example of R ₁₂ , R ₁₃ , R ₁₄ interconnecting to form a cyclic structure with a nitrogen atom is R ₁₂ , R ₁₃
When a cyclic structure (e.g. pyrrolidine, piperidine, morpholine, etc.) is formed by (R ₁₄ represents the same as shown above), and when R ₁₂ , R ₁₃ , R ₁₄ forms a cyclic structure (e.g. imidazole, 2-methylimidazole, triazole, pyridine, 2-methylpyridine, 3-methylpyridine, 4-methylpyridine, quinuclidine, etc.) are formed. X represents an anion, such as a halogen ion (e.g. chloride ion, bromide ion, etc.), an alkyl sulfate ion (e.g. methyl sulfate ion, ethyl sulfate ion), an alkyl or aryl sulfonate ion (e.g. methanesulfonate ion,
benzenesulfonate ion, etc.), acetate ion,
These include sulfate ions. n ₁ represents an integer from 0 to 2. In the general formula [], R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ are the same as R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ in the general formula [XII]. Q is a divalent group having 1 to 20 carbon atoms, examples of which are alkylene (e.g. methylene, ethylene, etc.), arylene (e.g.

[Formula] However, R is alkylene having 1 to 6 carbon atoms or a simple bond), -O-R'-
(However, R' is alkylene having 1 to 6 carbon atoms, such as -O-CH ₂ CH ₂ -, -O-CH ₂ CH ₂ CH ₂ -),

【formula】

[Formula] (R is the same as above), -NH-R′-,

[Formula] (R' is the same as above, R'' represents an alkyl group having 1 to 6 carbon atoms or an aralkyl group having 7 to 12 carbon atoms),

【formula】

[Formula] (However, R, R′, R″ are the same as above), etc. In the general formula [], R ₁₅ is an alkyl group having 1 to 12 carbon atoms or an alkyl group having 7 to 12 carbon atoms. This alkyl group and aralkyl group include substituted alkyl groups and substituted aralkyl groups. These examples are the same as those described for R ₁₂ , R ₁₃ , and R _14. R ₁₆ is Represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, etc. In the general formula (XI), the monomer unit represented by (B) is preferably one represented by the following general formula [] .General formula〔〕 In the formula, _R17 is a hydrogen atom or a methyl group, and P is a linking group for a vinyl group, such as amide (e.g. sulfonamide), ester (e.g. sulfonic acid ester), alkylene (e.g. methylene,
It is bonded to the vinyl group via ethylene, trimethylene), arylene (eg, phenylene, phenyleneoxycarbonyl), etc. Examples of the monomer represented by (B) include divinylbenzene, ethylene glycol dimethacrylate, propylene glycol dimethacrylate, neopentyl glycol dimethacrylate, tetramethylene glycol diacrylate, or trimethylolpropane triacrylate. m ₁ represents an integer from 2 to 4. The monomer unit represented by (C) in general formula (XI) is a copolymerizable ethylenically unsaturated monomer unit, and examples thereof include ethylene, propylene,
1-butene, sosobutene, styrene, α-methylstyrene, vinyltoluene, acrylic acid, methacrylic acid, monoethylenically unsaturated esters of aliphatic acids (e.g. vinyl acetate, allyl acetate), ethylenically unsaturated monocarboxylic acids or Esters of dicarboxylic acids (e.g. methyl methacrylate, ethyl acrylate, n-butyl acrylate, n-
Butyl methacrylate, n-hexyl methacrylate, n-octyl acrylate, benzyl acrylate, cyclohexyl methacrylate, 2-
These include ethylhexyl acrylate, monoethylenically unsaturated compounds (eg, acrylonitrile), or dienes (eg, butadiene, isoprene), and the like. (C) may contain two or more of the above monomer units. Among the basic latex polymers used in the present invention, particularly preferred monomer units represented by (A) are as follows. In the general formula [XII], R ₁₁ is a hydrogen atom, R ₁₂ , R ₁₃ and R ₁₄ are each the same or different atoms.
An alkyl group having ~3 carbon atoms and an alkyl group having a hydroxy group (1 to 3 carbon atoms), or R ₁₂ and R ₁₃ are linked together to form a piperidine ring with a nitrogen atom, and R ₁₄ is unsubstituted lower alkyl Particularly preferred are alkyl groups (having 1 to 3 carbon atoms), alkyl groups (having 1 to 3 carbon atoms) having a hydroxy group, and aralkyl groups. In the general formula [], R ₁₁ is a hydrogen atom or a methyl group, R ₁₂ , R ₁₃ and R ₁₄ are each the same or different one
An alkyl group having ~3 carbon atoms and an alkyl group having a hydroxy group (1 to 3 carbon atoms), or R ₁₂ and R ₁₃ are linked together to form a piperidine ring with a nitrogen atom, and R ₁₄ is an unsubstituted lower Alkyl group (1 to 3 carbon atoms), alkyl group (1 to 3 carbon atoms) having a hydroxy group, and aralkyl group, Q is -O-R'-, -NH-R'- (R' is ethylene, Propylene) is particularly preferred. In the general formula [XI], R ₁₅ is an alkyl group having 1 to 4 carbon atoms,
Alkyl group having hydroxy group (1 to 1 carbon atoms)
4) and an aralkyl group having 7 to 9 carbon atoms, R ₁₆ is particularly preferably a hydrogen atom or a methyl group. As for the monomer unit represented by (B), divinylbenzene, ethylene glycol dimethacrylate, propylene glycol dimethacrylate, etc. are particularly preferred. As for the monomer unit represented by (C), styrene, cyclohexyl methacrylate, methyl methacrylate, etc. are particularly preferred. x is 30 to 99 mol%, y is 1 to 8 mol%, z
is more preferably 10 to 80 mol%. X is a halogen ion (e.g. chloride ion),
alkyl sulfate ions (e.g. ethyl sulfate ions),
Acetate ion is particularly preferred. Specific examples of the basic latex polymer used in the present invention are shown below, but the present invention is not limited thereto (the exemplified polymers each contain the following repeating units in the following ratios). The basic latex polymer used in the present invention is JP-A-54-145529, JP-A No. 54-155835, JP-A No. 54-155835;
As shown in No. 54-126027 and No. 51-73440, it can be synthesized by ordinary emulsion polymerization. This emulsion polymerization is generally carried out using anionic surfactants (such as those commercially available from Rohm & Haus under the name Triton 770) or cationic surfactants (such as cetyltrimethylammonium chloride, stearyltrimethylammonium chloride, or nonionic surfactants). agent (e.g. polyvinyl alcohol)
This is carried out in the presence of at least one surfactant selected from among them and a radical initiator (for example, a combination of potassium persulfate and potassium bisulfite). The following two synthesis methods can be applied to the synthesis of latex polymers having monomer units represented by the general formulas [] and []. One method is to use at least two of the methods shown in (B) and (C).
Copolymerizable monomers having ethylenically unsaturated groups and copolymerizable ethylenically unsaturated monomers and unsaturated monomers represented by the following general formula ['] or ['] (however, R ₁₁ , X, n ₁ , Q is the same as shown above) after emulsion polymerization,

【formula】

【formula】

It can be synthesized by quaternization with an amine having the structure of [Formula] (where R ₁₂ , R ₁₃ , and R ₁₄ are the same as described above). In addition, as another method, copolymerizable unsaturated monomers shown in (B) and (C) and the following general formula ['']
or unsaturated monomers indicated with [″] (however,
R ₁₁ , R ₁₂ , R ₁₃ , Q are the same as above)
It can be synthesized by emulsion polymerization with and then quaternization with R ₁₄ --X (where R ₁₄ and X are the same as described above).

【formula】

[Formula] A latex polymer having monomer units represented by the general formula [] is a copolymerizable unsaturated monomer represented by (B) and (C) with the following general formula [′]
After emulsion polymerization with the unsaturated monomer shown in (however, R ₁₆ is the same as shown above), R ₁₅ -X
(However, R ₁₅ and X are the same as shown above.) It can be synthesized by quaternization. Basic latex polymers can be made into paper, woven fabrics, non-woven fabrics, etc. by internal addition, impregnation, coating, etc.
It is contained in supports such as plastic films, wooden boards, metal plates, and glass plates. The content of basic latex polymer is 0.1/ ^m2 of support.
~20g is preferred. Particularly preferred is 0.5 to 5 g.
The optimum content varies depending on the type and composition of the polymer, the inkjet amount of the water-based ink, the type and amount of dye in the water-based ink, the type of support and the method of containing the polymer, but can be determined by the person concerned. . Methods for incorporating the basic latex polymer into the support include an internal addition method in which the polymer is added to a pulp dispersion and paper is made; an impregnation method in which the polymer is absorbed into the voids of an absorbent support such as paper or cloth; A coating method is employed in which a polymer coating layer is formed on the surface of the support. Of these methods, the coating method is the most suitable because the basic latex polymer exhibits a water-resistant effect with a smaller amount and clear recorded images can be obtained. Coating liquids containing basic latex polymers can be used with air knife coaters, blade coaters, bar coaters, gravure coaters, curtain coaters,
It is applied to a support using a roll coater, spray, etc. The basic latex polymer according to the present invention includes pigments commonly used in paper processing, water-soluble polymers, latexes other than the present invention, synthetic resin emulsions, wetting agents, surfactants, dyes, ultraviolet absorbers, and pigments. It may be used in combination with a dispersant, antifoaming agent, antifungal agent, waterproofing agent, etc. Pigments include clay, talc, calcium carbonate, barium sulfate, zinc oxide, titanium white,
Synthetic silicate, silica, diatomaceous earth, fine polyethylene powder, fine polystyrene powder, fine urea resin powder, etc. are used, and they have ink absorbency, anti-stick properties,
Properties such as whiteness and smoothness can be imparted. Examples of water-soluble polymers include oxidized starch, cationic starch, gelatin, casein, hydroxyethylcellulose, polyvinyl alcohol, polyacrylamide, polyethylene oxide, polyvinylpyrrolidone, polyethyleneimine, polyamide polyamine, polyamide-polyamine-epichlorohydrin resin, etc. Used for purposes such as prevention, adjusting ink absorption, and adhesion of pigments. Latexes and emulsions such as styrene-butadiene copolymers, methyl methacrylate-butadiene copolymers, and acrylic acid ester copolymers are used for purposes such as adhesion of pigments and adjustment of ink absorption. Wetting agents such as glycerin and polyethylene glycol to improve water absorption, surfactants, dyes for blue tinting, and ultraviolet absorbers to improve the light resistance of dyes in water-based inks. , for example, substituted-2-hydroxyphenylbenzotriazole (trade name Tinuvin), hydroxybenzophenone,
Furthermore, antioxidants such as tert-butylhydroxyanisole, butylated hydroxytoluene, 2,5-di-tert-butylhydroquinone, and substituted chromanol, dispersants for dispersing pigments, and antifoaming agents for defoaming coating solutions. , a fungicide, a water resistance agent that mainly crosslinks water-soluble polymers, etc. may be added depending on the purpose. When inkjet recording is performed on an inkjet recording sheet containing a basic polymer latex according to the present invention with an aqueous ink containing the dye having an anionic dissociative group, the dye in the aqueous ink and the inkjet recording sheet are mixed with each other. The basic polymer latex is ionically bonded and the dye becomes insolubilized, completely preventing dye elution. Basic polymer latex is water-soluble and the dye has a strong mordant power, so inkjet recorded images are completely water resistant, and even if the inkjet recorded image is exposed to water or immersed in water for a long time, the image will remain intact. No change is observed at all. Particularly for multicolor inkjet recording, it is essential to use a recording sheet with good ink absorption to prevent ink from flowing out.
This results in a decrease in resolution and color reproducibility. However, when inkjet recording is performed on an inkjet recording sheet containing a basic polymer latex with good ink absorption properties according to the present invention, ink does not run out, and the density, resolution, and color reproducibility are improved. An extremely clear inkjet recorded image with excellent quality can be obtained. This is because the dye in the water-based ink is selectively adsorbed to the basic polymer latex in the recording sheet and does not diffuse in the lateral and thickness directions of the recording sheet. Water, a water-miscible organic solvent, a wetting agent, etc. in the water-based ink diffuse in the lateral and thickness directions of the recording sheet, so no ink runs out. The present invention will be explained in more detail with reference to Examples below. Example 1 The inkjet color printing method of the present invention was carried out using the following elements. (1) Yellow ink dye (Y-1); 2.8 parts by weight diethylene glycol; 1.0 parts by weight 2,2'-thiodiethanol nonionic surfactant; 16.0 parts by weight ;0.2 parts by weight Water; 80.0 parts by weight After stirring the above mixture for 1 hour while heating it to 40-50℃, filter it through a 0.8μ, 47φ microfilter FM.
A yellow ink was obtained by applying pressure (3 kg/cm ² ) using a type (manufactured by Fuji Photo Film Co., Ltd.). (2) Magenta ink dye (M-8); 1.2 parts by weight diethylene glycol monoethyl ether
; 0.5 parts by weight N-methyl-2-pyrrolidone nonionic surfactant ; 15.0 parts by weight ; 0.3 parts by weight Water; 83.0 parts by weight A magenta ink was obtained in the same manner as in the case of the yellow ink. (3) Cyan ink dye (C-1); 2.4 parts by weight diethylene glycol monobutyl ether
0.5 parts by weight N-methyl-2-pyrrolidone 10.0 parts by weight N-hydroxyethyl lactamide nonionic surfactant 5.0 parts by weight ; 0.1 part by weight Water; 82.0 parts by weight A cyan ink was obtained in the same manner as in the case of the yellow ink. (4) Recording sheet Basic latex polymer of the present invention (1)
; 28.5 parts by weight synthetic zeolite; 28.5 parts by weight gelatin; 28.5 parts by weight hydroxyethyl cellulose; 11 parts by weight hardener; 3 parts by weight surfactant; 0.03 parts by weight The above mixture was used as a coating liquid with a solid content of 12.3% by weight. It was coated on one side of high-quality base paper with a basis weight of 152 g/m ² and a cob size of 2 g/m ² at a solid content of 9.2 g/m ² using a bar coating method and dried. Next, the coated surface was smoothed through a super calender. (5) Color inkjet printing device Image information input means...color separation photometric system of drum scanner image information input means Spectral sensitivity characteristics...shown in Figure 2 Recording means...magnetic disk (recording capacity 40MB) Head position detection means...pulse counter Image information processing means: Panahuacom U-1500 minicomputer Inkjet ejection head: On-demand head Head drive frequency: 20KHz (6) Color correction formula A 10-term color correction formula consisting of a linear term, a quadratic term, and a constant term in the matrix equation described above. Using the above combination, a 24-color Macbeth color chart was photographed and printed on color paper, and an inkjet print reproduction image was created using it as an input image, and the color reproduction characteristics shown in Figure 3 were obtained. This figure 3 is from CIE1964 (U ^* ,
V ^* , W ^* ) Chromaticity is expressed using a color system. On the other hand, in order to compare with the color reproduction characteristics of the present invention,
When an inkjet print reproduced image was produced in the same manner using the inkjet color printing method shown below, the color reproduction characteristics shown in FIG. 4 were obtained. From the comparison between FIG. 3 and FIG. 4, it was confirmed that the inkjet color printing method of the present invention has significantly improved color reproduction characteristics. (1′) Yellow ink

[Table] Comparative yellow ink was obtained in the same manner as in the case of the yellow ink. (2′) Magenta ink

[Table] Dyes listed in the issue)

[Table] Comparative magenta ink was obtained in the same manner as in the case of the yellow ink. (3′) Cyan ink

[Table]

[Table] Comparative cyan ink was obtained in the same manner as in the case of the yellow ink. (4') Recording sheet Synthetic zeolite; 40 parts by weight Gelatin; 40 parts by weight Hydroxyethyl cellulose; 15.5 parts by weight Hardener; 4 parts by weight Surfactant; 0.05 parts by weight The above mixture was applied at a solid content of 12.3% by weight. The liquid was coated on one side of high-quality base paper with a basis weight of 152 g/m ² and a cob size of 2 g/m ² at a solid content of 6.6 g/m ² using a bar coating method and dried. Next, the coated surface was smoothed by passing it through a super calender. (5') Color inkjet printing device The same color inkjet printing device as described in (5) above. (6') Color correction formula A three-term color correction formula consisting of only the first-order term in the matrix formula described above. Example 2 The same yellow ink, magenta ink, cyan ink, and color ink jet printing device and color correction formula as in Example 1 were used, and the following black ink and recording sheet were used. Black ink dye (CI Acid Black155); 3.5 parts by weight diethylene glycol monoethyl ether
; 1.0 parts by weight N-methyl-2-pyrrolidone ; 20.0 parts by weight 2,2'-thiodiethanol nonionic surfactant
;20.0 parts by weight ; 0.1 parts by weight Water ; 55.4 parts by weight Recording sheet: 5 parts by weight of the polymer shown in Table ¹ below, 5 parts by weight of bilatin, and a ^composite of An aqueous solution containing 5 parts by weight of aluminum silicate was applied using an air knife coater to give a dry solid content of 7.5 g/m ² and calendering was performed to prepare inkjet recording sheets 1 to 5. The above-mentioned water-based inks of cyan, magenta, yellow, and black are jetted onto the thus obtained recording sheets 1 to 5 using a multicolor inkjet printer having four inkjet nozzles to form monochrome and 2 to 4-color inks. Overlapping records were made. The water resistance and image density of the thus recorded image were measured and the results shown in Table 1 were obtained.

[Table] As is clear from Table 1, when recording sheets 1 to 3 containing the polymer according to the present invention were used, the image water resistance was extremely excellent and there was no change in the image due to water immersion. Also, regarding image density, the recording sheet containing the polymer according to the present invention exhibited higher image density than those used for comparison. Example 3 100 parts of LBKP was beaten to a water content of 430 c.c., and 0.2 parts of polyamide-epichlorohydrin resin was added.
A base paper with a basis weight of 100 g/m ² was made using a Fourdrinier paper machine to obtain an inkjet recording sheet-6. On record sheet 6, add a commercially available mordant (Sanyo Chemical Co., Ltd.)
Inkjet Recording Sheet-7 was prepared by impregnating 3 g/m ² of dry solids from Sun Fixtures 70) manufactured by San Francisco Co., Ltd. Further, recording sheet-6 was impregnated with the basic latex polymer of compound example (5) according to the present invention at a dry solid content of 3 g/m ² to prepare inkjet recording sheet-8. Using the thus obtained inkjet recording sheet, multicolor inkjet recording was carried out in the same manner as in Example 2, and the results shown in Table 2 were obtained.

[Table] * Density of solid area of cyan ink In the recording sheet 8 according to the present invention, there is no change in the image due to water immersion, there is little ink diffusion, and the image density is high. Example 4 Commercially available No. 40 single yarn warp and weft each 1 inch long 70
Inkjet recording sheet for book calico cloth - 9
And so. Record sheet - 5 pieces of polyethyleneimine on the cloth from 9
The inkjet recording sheet-10 was obtained by impregnating the inkjet recording sheet with an inkjet recording sheet of 10 g/m ² and drying it. The cloth of Recording Sheet-9 was impregnated with 5 g/m ² of latex polymer of Compound Example (5) of the present invention, and dried to obtain Inkjet Recording Sheet-11. Inkjet recording sheet thus obtained
Multicolor inkjet recording was carried out in the same manner as in Example 2 on samples Nos. 9 to 11. When these inkjet-recorded fabrics were washed with water, the fabric of recording sheet 11 according to the present invention had no dye elution at all, and there was no change in the image after washing and drying, whereas the comparative recording sheet 10 did not. , the dye was eluted considerably, and the image density became considerably low after washing with water and drying. Furthermore, a recording sheet for comparison - 9
Most of the images have disappeared. Example 5 5 parts by weight of the latex of Compound Example-2 of the present invention as a basic latex polymer, 3 parts by weight of gelatin, 0.3 parts by weight of polyamide-polyamine-epichlorohydrin resin, and Apply a coating solution consisting of 5 parts by weight of calcium carbonate to 5 parts by weight on one side with a dry solid content.
The inkjet recording sheet-12 was prepared by coating with a g/m ² bar coater and drying. Ink jet recording sheet-13 was prepared in the same manner as recording sheet-12 except that no basic latex polymer was used. Example 2 using this inkjet recording sheet
Multicolor inkjet recording was performed in the same manner as in . The results are shown in Table 3. Recording sheet related to the present invention
In No. 12, there was no ink flow during inkjet recording, the image had good water resistance, and there was no change at all due to water immersion.

[Table] *1 A phenomenon in which ink flows out in areas where two and three colors overlap.
*2 Density of solid area of cyan ink.

[Brief explanation of the drawing]

Figure 1 is a block diagram of the color inkjet printing device of the present invention, Figure 2 is a characteristic curve diagram that approximates the spectral sensitivity characteristics of the CIE color matching function, and Figure 3 is a diagram showing the color reproducibility of the color printing method of the present invention. FIG. 4 is a characteristic diagram showing the color reproducibility of a conventional example. 1...Digital color scanner, 2...Image information processing device, 3...Printer, 11...Color original picture, 12
...Main scanning pulse motor, 13...Main scanning counter,
28... Sub-scanning pulse motor, 29... Sub-scanning counter, 34... Central processing unit, 35... Storage device,
36...Line buffer memory section, 37...UCR section,
38...Table memory unit, 39...Head drive unit,
42... Blank paper, 43... Head unit, 44... Main scanning pulse motor, 45... Main scanning counter, 54... Sub-scanning pulse motor, 55... Sub-scanning counter.

Claims (1)

[Scope of Claims] 1. Image information input means for inputting blue, green, and red density signals of each point of a color image in the form of digital signals, storage means for storing the input digital signals, and inkjet ejection onto a recording medium. a position detecting means for detecting the position of the head; an image information processing means for reading out a digital signal by specifying an address in the storage means with a signal from the position detecting means; and correcting the read digital signal; head driving means for controlling the ejection amounts of cyan, magenta, and yellow ink by driving at least the inkjet ejection heads for cyan, magenta, and yellow, respectively, according to digital signals from the inkjet ejection head and at least the recording medium; In an inkjet color printing system in which a color image is recorded by a color inkjet printing device consisting of a scanning means that moves one side to two-dimensionally scan a recording medium, when recording a color image, the blue, green,
Masking processing is performed using a polynomial including a non-linear term with a red density signal as a variable; the yellow ink is an aqueous ink containing a yellow dye selected from a compound represented by the following general formula []; Magenta ink has the following general formula [-
a], [-b] or [-c]; the cyan ink is a cyan dye selected from compounds represented by the following general formula []; An inkjet color printing method characterized in that the ink is an aqueous ink containing a basic latex polymer, and the recording medium is a sheet containing a basic latex polymer. General formula []: Yellow dye In the general formula [], R ₁ represents an amino group or an acylamino group. R ₂ represents a phenyl group, a substituted phenyl group, a lower alkyl group or a substituted lower alkyl group. R ₃ represents a lower alkyl group or a phenyl group. X ₁ represents a halogen atom, a lower alkyl group, an alkoxy group, a sulfo group, a carboxyl group, an amino group, a substituted amino group, a cyano group, an alkylsulfonyl group, a nitro group, a hydroxyl group, a ureido group, or an alkoxycarbonyl group. j represents 0, 1, 2 or 3, and when j is 2 or 3, X ₁ may be the same or different. The number of sulfo groups in the general formula [] is 1 to 3. General formula [-a]: Magenta dye In the general formula [-a], R ₄ is a cyan group,
Alkylsulfonyl group, arylsulfonyl group,
Represents a trifluoromethyl group, trichloromethyl group, or a halogen atom. R ₅ represents an amino group, an acylamino group, a substituted ureido group, an alkoxy group or an acyloxy group. R ₆ represents a hydrogen atom, a lower alkyl group, a phenyl group or an acyl group. k indicates 0 or 1. General formula [-b]: Magenta dye In the general formula [-b], R ₇ is a hydrogen atom,
Represents an acyl group, lower alkyl group or phenyl group. X ₂ represents a halogen atom, a lower alkyl group, an alkoxy group, a sulfo group, a carboxyl group, an amino group, a substituted amino group, a cyan group, an alkylsulfonyl group, a nitro group, a hydroxyl group, a ureido group, or an alkoxycarbonyl group. l represents 0 or 1, m represents 0, 1, 2 or 3, and when m is 2 or 3, X ₂ may be the same or different. General formula [-c]: Magenta dye In the general formula [-c], R ₈ is a hydrogen atom,
Represents a lower alkyl group or phenyl group. _R9
represents a hydrogen atom, a lower alkyl group, a phenyl group, an alkoxycarbonyl group, a carboxy group or a cyano group. X ₃ represents a lower alkyl group, a halogen atom, an alkoxy group, a carboxy group, a cyano group, a hydroxy group or a nitro group. X ₄ represents a hydrogen atom or a lower alkyl group. n is 1,2
Or represents 3. p is 0, 1, 2, 3 or 4
represents. When p is 2 or more, X ₃ may be the same or different. General formula []: Cyan dye In the general formula [], q represents 1, 2, 3 or 4. However, the general formula [], [-a], [-b], [
-c] or the sulfo group in [] may be an alkali metal salt, ammonium salt or organic amine salt. 2. The inkjet color printing method according to claim 1, wherein the nonlinear term is a quadratic equation. 3. The three color density signals are obtained using a color separation photometry system having spectral sensitivity characteristics obtained by using a CIE color matching function or a linear combination thereof. Inkjet color printing method described.