JP2004341505A - Generation method of area gradation image - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a generation method of a dot area modulation image by which a color tone can stably be reproduced even when a percentage of black dots varies. <P>SOLUTION: In the dot area modulation image generation method with a means to independently control dot density and dot gain, a change of dot gain to a density change of a magenta image is 10-30 in 30% dots. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a proof for confirming the finish of a printed matter in advance, and more particularly, to a proof image forming method capable of changing a halftone dot density, stabilizing a color tone even when a dot% such as a black dot changes. And methods that can be reproduced.

  Silver halide light-sensitive materials are widely used today because of their high sensitivity, excellent color reproducibility, and suitability for continuous processing. Due to these characteristics, silver halide light-sensitive materials have been widely used not only in the field of photography but also in the field of printing, in the field of so-called proofing for checking the state of the finished printed matter in the middle of printing. ing.

  In the field of proofing, an image edited on a computer is output to a printing film, and the developed film is appropriately replaced and subjected to decomposing exposure to obtain yellow (Y), magenta (M), and cyan (C). By forming an image and forming an image of the final printed matter on color photographic paper, it has been performed to determine the suitability of the layout and color of the final printed matter.

  Recently, a method of directly outputting an image edited on a computer to a printing plate has gradually become widespread. In such a case, it is desired to obtain a color image directly from the data on the computer without using a film. Had been rare.

  For this purpose, various methods such as sublimation type / fusion heat transfer method, electrophotographic method, and ink jet method have been tried, but the method of obtaining high quality images is expensive and the productivity is inferior. There is a disadvantage that the system which is low in cost and has high productivity has poor image quality. A system using a silver halide photosensitive material enables high-quality image formation, such as formation of an accurate halftone image, due to excellent sharpness and the like, while continuous processing is possible as described above. In addition, since images can be simultaneously written in a plurality of color image forming units, high productivity can be realized.

  In recent years, in the field of printing, so-called digitization has progressed, and there has been an increasing demand for obtaining images directly from data in a computer. For the reasons described above, silver halide photosensitive materials have begun to be advantageously used in this field.

  The area gradation image is basically expressed by the binary values of the density of the halftone dot and the dropout (non-halftone portion). However, when forming the proof image, it is very necessary to design the density so that the density can be changed. A useful proof system can be provided. When a silver halide photosensitive material is used as such a system, an image formation can be completed by one exposure and development, and a very useful system is constructed because no additional material is required. This is the most preferred embodiment. For this reason, the following description focuses on a system using a silver halide photosensitive material.

  When using paper called art paper or coated paper as printing paper, and when using paper called high-quality paper, the finish is not the same even if other conditions are the same. This is mainly due to the fact that in the case of high-quality paper, paper fibers are exposed on the surface, and the density is reduced due to the penetration of ink into the paper. In the proof image forming method, by changing the density of the halftone dots, it is possible to reproduce the state of printing on art paper and at the same time to reproduce the state of printing on high quality paper, which is very useful. It is possible to make a simple system. An apparatus using a silver halide photosensitive material has been proposed as a proof image producing apparatus, and it is disclosed that the density of halftone dots can be changed (for example, see Non-Patent Document 1). Also disclosed is a color image proofing device using a color photosensitive material, which adjusts the color density by adjusting the amount of light transmitted by adjusting the ON and OFF voltage values applied to an AOM (acousto-optic modulator). (See, for example, Patent Document 1), which discloses that the color density and the density of a blank portion can be varied to form an image similar to that of printing, and that calibration of special color printing is possible. However, these documents do not describe the instability of the color tone that occurs when the dot% such as the black dot changes, which occurs in the area gradation image forming method in which the density of the dot portion can be changed. There is no suggestion for a solution.

  In a system that forms an area gradation image based on digital data, a halftone dot is divided into smaller units (here, this is expressed as a pixel), and the pixel is exposed at an appropriate exposure amount to form an aggregate. It is possible to reproduce halftone dots. As a simple example, if one halftone dot is composed of 100 pixels, 50% of the halftone dots are colored by exposing 50 pixels so that they can be developed. Can be formed. The difference between the dot% of the image data and the dot% of the reproduced area gradation image is called a dot gain. The dot gain can be arbitrarily adjusted by adjusting the number of pixels to be exposed. On the other hand, an image forming method has been disclosed in which the density and the dot gain using a directly modulated LED as a light source are independently adjusted (for example, see Patent Document 2), and a proof image having a small difference from a printed image can be easily obtained. Is disclosed. However, in such a system, there is no description about the instability of the color tone which occurs when the dot% such as the ink dot changes. In such a system, it has been shown that the phenomenon that the color tone of the halftone dot portion of three-color black which occurs when continuous output is performed is improved by using a directly modulated LED as a light source (for example, , Patent Document 3), suggesting that the above phenomenon is directly caused by the characteristics of the light source and the optical system of the exposure apparatus. Therefore, it is understood that the phenomenon is essentially different from the problem of the present application.

  In an area gradation image forming method for directly or indirectly detecting the surface temperature of a silver halide photosensitive material fixed to an exposure drum and controlling an exposure amount based on the surface temperature information, the sensitivity of the silver halide photosensitive material is It discloses that when the relationship between the temperature and the temperature satisfies a specific relationship, the variation in density due to the variation in temperature can be suppressed (see, for example, Patent Document 4), and further discloses a method for obtaining such a photosensitive material. ing. In this, the relationship between sensitivity and temperature is defined by the same formula as the GOF value of the present invention. However, Patent Literature 4 merely uses this expression method to define linearity, and does not mention any instability of color tone that occurs when a dot% such as a black dot net changes. . Further, there is no description as to what range of the GOF value is effective.

  The claims of Patent Document 2 disclose a silver halide photosensitive material containing a C coupler represented by the general formula (1) or (2) of the present application. The effect is described in No. 4, but it only discloses that it is excellent in cyan and green color reproduction in addition to the effect of the above-mentioned invention, and does not disclose any problem of the present invention.

The resin coating layer on the reflective support has at least one hydrophilic colloid layer containing a white pigment between the resin coating layer and the silver halide photographic emulsion layer, and the resin coating layer on the side having the emulsion layer has irregularities. The silver halide photographic light-sensitive material satisfies the conditions specified in the winner spectrum. It is disclosed that it can be obtained (for example, see Patent Document 5). Further, the embodiment of Patent Document 3 discloses an example in which a silver halide photosensitive material having a white pigment layer is used for a digital color proof. However, there is no mention of instability of the color tone that occurs when the dot% such as the ink dot changes, and no solution is suggested.
Digital Consensus Pro Brochure, Konica Graphic Imaging Inc. (2002) JP-A-5-66557 (Claims) JP 2001-305701 A (Claims) Japanese Patent Application Laid-Open No. 2001-305701 (Claims, Examples) Japanese Patent Application Laid-Open No. 2002-221774 (Claims) Japanese Patent Laying-Open No. 7-104592 (Claims)

  SUMMARY OF THE INVENTION It is an object of the present invention to provide an area gradation image forming method for preventing a color tone from becoming unstable when a dot% such as a black dot changes in a proof image forming method capable of changing a dot density. is there.

  The above object of the present invention can be achieved by the following configurations.

(Claim 1)
An area gradation image forming method having means for independently controlling halftone dot density and dot gain, wherein a change in dot gain with respect to a change in density of a magenta image is 10 to 30 at 30% of halftone dot. Area gradation image forming method.

(Claim 2)
The relationship between the density of the magenta image and the dot gain was determined by the following equation 1 at five equally spaced points between the halftone dot density -0.1 and the halftone dot density +0.1 in the black plate or special color plate. 2. The area gradation image forming method according to claim 1, wherein the GOF value is 1 or less.

(Equation 1) GOF = {Σ (DG ai -DG ci) 2/4} 1/2
Wherein, DG _a represents the dot gain at each solid density, DG _c represents the value when computing the dot gain at each solid density by the following equation (2). i represents a data number and represents one of 1 to 5. ]
(Equation 2) DG _c = a × D + b
[Where D represents the solid density, and a and b both represent constants determined by the least squares method. ]
(Claim 3)
An area gradation image forming method having means for independently controlling halftone dot density and dot gain, wherein a change in dot gain with respect to a change in density of a cyan image is 5 to 25 at 30% of halftone%. Area gradation image forming method.

(Claim 4)
4. The area gradation image forming method according to claim 3, wherein a silver halide photosensitive material containing at least one selected from cyan couplers represented by the following general formula (1) or (2) is used. Method.

[In the formula, R ₁ represents a hydrogen atom or a substituent, and R ₂ represents a substituent. m represents the number of substituents R ₂ . When m is 0, R ₁ represents an electron-withdrawing group having a Hammett's substituent constant σp of 0.20 or more. When m is 1 or 2 or more, at least one of R ₁ and R ₂ is substituted by Hammett. Represents an electron-withdrawing group having a group constant σp of 0.20 or more.

Z ₁ represents a nonmetallic atom group necessary to form a nitrogen-containing 5-membered heterocyclic ring which may be condensed with a benzene ring or the like.

R ₃ and R ₄ each represent an electron-withdrawing group having a Hammett's substituent constant σp of 0.20 or more. However, the sum of the σp values of R ₃ and R ₄ is 0.65 or more. Z ₂ represents a group of nonmetal atoms necessary for forming a nitrogen-containing 5-membered heterocyclic ring, and the 5-membered ring may have a substituent.

X ₁ and X ₂ each represent a hydrogen atom or a group which is released by a coupling reaction with an oxidized form of a color developing agent. ]
(Claim 5)
5. A silver halide photosensitive material having at least one layer containing 35% by mass or more of a white pigment between a support and a silver halide emulsion layer closest to the support. The method for forming an area gradation image according to any one of the above items.

  According to the present invention, in a method of forming a proof image in which the halftone dot density can be changed, an area gradation image forming method capable of stably reproducing a color tone even when a dot% such as a black dot changes is provided. Was completed.

  The present invention will be described in more detail. One of the features of the present invention resides in an area gradation image forming method including means for controlling dot density and dot gain independently. The usefulness and the like of this image forming method have already been described, but as a result of the study of the present inventors, in such a system, the color%, the sum of the two or more basic colors, the black, and the dot% of the special color changed. It was found that a phenomenon that the color tone sometimes fluctuated was observed.

  In the case of a silver halide light-sensitive material, it is necessary to use an area where the density can be changed by a change in the exposure amount, and in consideration of the dynamic range of the light source, the exposure amount (unless otherwise obvious, use the usual exposure amount unless otherwise specified). It is necessary to use a region in which the ratio between the logarithm and logH) and the concentration changes significantly. In this case, two or three regions may be used as the ratio between the density change and the exposure change. In some cases, four or more regions may be used. In such a system, the amount of light that has exposed the pixel is reduced at the peripheral portion due to diffusion, so that the density around the pixel is reduced. In the case of black, special colors, or the like in which two or more colors are formed, the size of each color pixel is slightly different. Although the cause has not been fully elucidated, it is probable that such a phenomenon causes a phenomenon in which the color tone fluctuates when the dot percentage of the black ink and the special color changes.

  One of the features of the present invention is that a change in dot gain with respect to a change in density of a magenta image is 10 to 30 at 30% of dot%. Of the pixels constituting the halftone dot, 30% of the pixels are exposed to light with changing the exposure amount, and the density is measured. At the same time, a sample is prepared by exposing all the pixels with the same exposure amount, and the density is also measured. From these data, the dot% reproduced from, for example, the Murray-Davis equation can be obtained, and the dot gain can be calculated. When the solid density is plotted on the horizontal axis and the dot gain is plotted on the vertical axis, in a region used for forming an area gradation image, a curve almost in a straight line is obtained in which the dot gain increases as the density increases. . The gradient of the tangent to the curve at the density of the halftone dot portion is the change of the dot gain with respect to the change of the density.

  The dot gain can be adjusted by adjusting the halftone dot density according to the exposure amount and controlling the number of pixels to be exposed. However, as described above, a specific relationship is established between the number of pixels to be exposed and the dot gain of an image depending on the exposure amount. Although this effect is not so large, halftone dots obtained by superimposing two or more colors, particularly colors close to neutral gray such as black netting, are conspicuous and impair the quality of an obtained image.

  At this time, by changing the number of pixels to be exposed variously, the above relationship can be obtained for an arbitrary dot%. These are not independent and can be represented by 30% data because they are strongly correlated if the difference between the halftone dots is small. If the number of pixels to be exposed is small, the change in dot gain with respect to the change in density becomes small, making it difficult to correlate with the change in color tone due to the change in dot%. A typical characteristic is that the dot% is specified on the condition of 30%. It was confirmed that

  According to the study of the present inventors, it is found that the characteristic of the M image has a large influence particularly in the case of the color tone of the black screen, and the change of the dot gain with respect to the density change is suppressed to 10 to 30 at 30% of the screen%. By doing so, an excellent effect can be obtained. It is preferably from 15 to 28, and more preferably from 20 to 25.

  As for the magnitude of the influence on the black net, the C image has the next largest effect. An excellent effect can be obtained by suppressing the change of the dot gain with respect to the density change from 5 to 25 at 30% of the halftone dot. It is preferably 10 to 22, and more preferably 15 to 20.

  The “density” may be the status T, the status A, or whatever as the spectral condition, but is preferably the status T because it is used in the printing field. The geometric condition may be any of 0-45, 45-0, or d-0, D-0 (defined in JIS Z 8722-1982 4.3.1 Geometric condition of illumination and light reception), The geometric condition is preferably 0-45 or 45-0.

  One of the features of the present invention is that, with respect to the relationship between the density of the magenta image and the dot gain, the density is set at an equal interval between halftone dot density-0.1 to halftone dot density + 0.1 in the black plate or the special color plate. The GOF value obtained by equation (1) at five points is 1 or less. The GOF value is preferably 0.8 or less, more preferably 0.5 or less. The density range that satisfies this relationship is preferably as wide as possible, and the GOF value is 1 or less at five equally spaced points between the dot density of −0.2 and the dot density of +0.2 in the black plate or special color plate. Is preferred.

  As the silver halide emulsion used in the present invention, a silver halide emulsion comprising 95% by mole or more of silver chloride is preferable, and any halogen such as silver chloride, silver chlorobromide, silver chloroiodobromide and silver chloroiodide can be used. Those having a composition are used. Among them, a silver chlorobromide containing 95 mol% or more of silver chloride, particularly a silver halide emulsion having a portion containing silver bromide in a high concentration is preferably used. Silver chloroiodide containing about 0.5 mol% is also preferably used. In the silver halide emulsion having a portion containing silver bromide at a high concentration, the portion containing silver bromide at a high concentration may be a so-called core-shell emulsion or may be simply formed without forming a complete layer. A so-called epitaxy junction region in which only a region having a partially different composition may exist may be formed. It is particularly preferable that the portion where silver bromide exists at a high concentration is formed at the top of crystal grains on the surface of silver halide grains. Further, the composition may change continuously or may change discontinuously.

It is advantageous that the negative-working silver halide emulsion used in the present invention contains a heavy metal ion. This is expected to improve so-called reciprocity failure and prevent desensitization in high-illuminance exposure and softening on the shadow side. Examples of heavy metal ions that can be used for such purposes include Group 8 to 10 metals such as iron, iridium, platinum, palladium, nickel, rhodium, osmium, ruthenium, and cobalt; and twelfth metals such as cadmium, zinc, and mercury. Group transition metals and each ion of lead, rhenium, molybdenum, tungsten, gallium, and chromium can be mentioned. Among them, metal ions of iron, iridium, platinum, ruthenium, gallium, and osmium are preferable. These metal ions can be added to the silver halide emulsion in the form of a salt or a complex salt. When the heavy metal ion forms a complex, as the ligand, cyanide ion, thiocyanate ion, cyanate ion, chloride ion, bromide ion, iodide ion, carbonyl, nitrosyl, ammonia, water, pyridine, Pyrrole, pyrazole, imidazole, thiazole, 1,2,4-triazole, 2,2'-biimidazole, 2,2'-bipyridine or 2,2 ': 6', 2 "-terpyridine compound is preferably used. , Cyanide ion, chloride ion, bromide ion, water, nitrosyl, 5-methylthiazole, 1,2,4-triazole, etc. In order to incorporate a heavy metal ion into a silver halide emulsion, the heavy metal compound must be Before the formation of silver halide grains, during the formation of silver halide grains, after the formation of silver halide grains In order to obtain a silver halide emulsion satisfying the above-mentioned conditions, a heavy metal compound is dissolved together with a halide salt and the whole or a part of the grain forming step is obtained. Alternatively, silver halide fine particles containing these heavy metal compounds may be formed in advance and prepared by adding the silver halide fine particles. The amount added to the emulsion is preferably from 1 × 10 ⁻⁹ mol to 1 × 10 ⁻² mol, more preferably from 1 × 10 ⁻⁸ mol to 5 × 10 ⁻⁵ mol per mol of silver halide. preferable.

  Any shape can be used for the particles used in the present invention. One preferable example is a cube having a (100) plane as a crystal surface. Also, U.S. Pat. Nos. 4,183,756 and 4,225,666, JP-A-55-26589, JP-B-55-42737, and The Journal of Photographic Science (J. Photogr. Sci., No. 21, p. 39 (1973), etc., can be used to produce particles having shapes such as octahedron, tetradecahedron, and dodecahedron, and to use these. . Further, particles having a twin plane may be used.

  As the grains used in the present invention, grains having a single shape are preferably used, but it is particularly preferable to add two or more kinds of monodispersed silver halide emulsions to the same layer.

  The particle size of the particles used in the present invention is not particularly limited, but is preferably 0.1 to 1.2 μm, more preferably 0.2 to 1.2 μm in consideration of other photographic properties such as rapid processing property and sensitivity. １．０1.0 μm.

  This particle size can be measured using the projected area or diameter approximation of the particle. If the particles are substantially uniform in shape, the particle size distribution can represent this fairly accurately as diameter or projected area.

  The distribution of the grain size of the silver halide grains used in the present invention is preferably a monodispersed silver halide grain having a variation coefficient of 0.22 or less, more preferably 0.15 or less, and particularly preferably a variation coefficient of 0.1 or less. That is, two or more monodispersed emulsions of 15 or less are added to the same layer. Here, the variation coefficient is a coefficient representing the width of the particle size distribution, and is defined by the following equation.

Coefficient of variation = S / R
(Here, S represents the standard deviation of the particle size distribution, and R represents the average particle size.)
As the apparatus and method for preparing a silver halide emulsion, various methods known in the art can be used.

  The emulsion used in the present invention may be obtained by any of the acidic method, neutral method, and ammonia method. The particles may be grown at one time or may be grown after seed particles have been made. The method for producing the seed particles and the method for growing the seed particles may be the same or different.

  The form in which the soluble silver salt and the soluble halide salt are reacted may be any of a forward mixing method, a reverse mixing method, a simultaneous mixing method, and a combination thereof, but a method obtained by the simultaneous mixing method is preferable. Further, as one form of the double jet method, a pAg controlled double jet method described in JP-A-54-48521 can be used.

  Further, a device for supplying a water-soluble silver salt and a water-soluble halide salt solution from an addition device arranged in a reaction mother liquor described in JP-A-57-92523, JP-A-57-92524, etc. A device for continuously changing the concentration of an aqueous solution of a water-soluble silver salt and a water-soluble halide salt described in, for example, the reaction mother liquor is taken out of the reactor described in JP-B-56-501776, and subjected to ultrafiltration. An apparatus that forms grains while keeping the distance between silver halide grains constant by concentrating by a method may be used.

  If necessary, a silver halide solvent such as thioether may be used. Further, a compound having a mercapto group, a nitrogen-containing heterocyclic compound or a compound such as a sensitizing dye may be added at the time of forming silver halide grains or after the completion of grain formation.

  The negative-working silver halide emulsion used in the present invention can be used in combination with a sensitization method using a gold compound and a sensitization method using a chalcogen sensitizer. As the chalcogen sensitizer, a sulfur sensitizer, a selenium sensitizer, a tellurium sensitizer, or the like can be used, but a sulfur sensitizer is preferable. Examples of the sulfur sensitizer include thiosulfate, triethylthiourea, allylthiocarbamide thiourea, allylisothiocyanate, cystine, p-toluenethiosulfonate, rhodanine, and inorganic sulfur.

The amount of the sulfur sensitizer, it is preferred to vary the size, etc. of the effect of the type of silver halide emulsions applied or expectations, per mol of silver halide 5 × 10 ^-10 ~5 × 10 ^- A range of ⁵ mol, preferably 5 × 10 ^{−8 to} 3 × 10 ⁻⁵ mol is preferred.

As the gold sensitizer, various other gold complexes such as chloroauric acid and gold sulfide can be added. Examples of the ligand compound used include dimethyl rhodanine, thiocyanic acid, mercaptotetrazole, mercaptotriazole and the like. The amount of the gold compound used is not uniform depending on the type of silver halide emulsion, the type of compound to be used, the ripening conditions, etc., but usually 1 × 10 ⁻⁴ mol to 1 × 10 ⁻⁸ per mol of silver halide. Preferably it is molar. More preferably, it is 1 × 10 ⁻⁵ mol to 1 × 10 ⁻⁸ mol.

  The chemical sensitization of the negative silver halide emulsion used in the present invention may be a reduction sensitization.

  The silver halide emulsion used in the present invention is known for the purpose of preventing fogging generated during the step of preparing a silver halide light-sensitive material, reducing performance fluctuation during storage, and preventing fogging generated during development. Antifoggants and stabilizers can be used. Examples of preferred compounds that can be used for such purposes include the compounds represented by the general formula (II) described in the lower column on page 7 of JP-A-2-14636, and more preferred specific compounds are Are the compounds of (IIa-1) to (IIa-8) and (IIb-1) to (IIb-7) described on page 8 of the publication and JP-A-2000-267235, page 8, right column 32-36. The compound described in the second row, the mercaptopyrimidine compound represented by the general formula (I) in JP-A-9-152677, and the substituted or unsubstituted group, Compounds having a hydroxyl group or an amino group, specifically, (I-1), (I-2), (I-7), (I-9), (II-1), and (II-3) The compounds represented may be mentioned. Further, compounds having a sulfide or polysulfide group shown in (A) to (D) of JP-A-10-31279 can be mentioned. Specifically, (C-1), (C-9), (C-14), (C-15), (C-16), (D-1), (D-6), α-sulfur, (I-4) and (I-) of JP-A-2000-122204. 6).

These compounds are added in a step of preparing silver halide emulsion grains, a step of chemical sensitization, a step of preparing a coating solution at the end of the step of chemical sensitization or a step of preparing a coating solution according to the purpose. When chemical sensitization is performed in the presence of these compounds, it is preferably used in an amount of about 1 × 10 ⁻⁵ mol to 5 × 10 ⁻⁴ mol per mol of silver halide. When added at the end of chemical sensitization, the amount is preferably about 1 × 10 ⁻⁶ mol to 1 × 10 ⁻² mol, and more preferably 1 × 10 ⁻⁵ mol to 5 × 10 ⁻³ mol per mol of silver halide. More preferred. In the coating solution preparation step, when added to the silver halide emulsion layer, the amount is preferably about 1 × 10 ^-6 mol to 1 × 10 ^-1 mol per mol of silver halide, and more preferably 1 × 10 ^-5 mol to 1 × 10 ^-2 mol is more preferred. When it is added to a layer other than the silver halide emulsion layer, the amount in the coating film is preferably about 1 × 10 ^-9 mol to 1 × 10 ^-3 mol per 1 m ² .

  In the photographic light-sensitive material used in the present invention, dyes having absorption in various wavelength ranges can be used for the purpose of preventing irradiation and halation. For this purpose, any of known compounds can be used. In particular, as dyes having absorption in the visible region, dyes of AI-1 to 11 described in JP-A-3-251840, p. The dyes described in JP-A-3770 are preferably used.

  The silver halide light-sensitive material according to the present invention comprises a hydrophilic colloid colored with at least one layer of a diffusion-resistant compound on the side closer to the support than the silver halide emulsion layer closest to the support among the silver halide emulsion layers. It is preferred to have a layer. As the coloring substance, a dye or another organic or inorganic coloring substance can be used.

  One of the features of the present invention resides in that at least one layer containing 35% by mass or more of a white pigment is provided between the support and the silver halide emulsion layer closest to the support. As the white pigment, for example, rutile-type titanium dioxide, anatase-type titanium dioxide, barium sulfate, barium stearate, silica, alumina, zirconium oxide, kaolin, etc., for various reasons, among them, titanium dioxide, especially rutile Type titanium dioxide is preferred. The white pigment is dispersed in an aqueous binder of a hydrophilic colloid such as gelatin, which allows the processing liquid to penetrate. The content of the white pigment is preferably 40% by mass or more, more preferably 60% by mass or more, but if it is more than this, problems occur in terms of fragility and coatability. The white pigment layer may contain the coloring substance.

The coating with the amount of the white pigment is preferably in the range of ^{0.1g / m 2 ~50g / m 2} , more preferably in the range of ^{0.2g / m 2 ~5g / m 2} .

  Between the support and the silver halide emulsion layer closest to the support, a non-photosensitive hydrophilic colloid layer such as an undercoat layer or an intermediate layer may be provided at any position in addition to the white pigment-containing layer, if necessary. Can be provided.

  It is preferable to add a fluorescent whitening agent to the silver halide light-sensitive material according to the present invention since whiteness can be further improved. The fluorescent whitening agent is not particularly limited as long as it is a compound capable of absorbing ultraviolet light and emitting visible light fluorescence, but is a diaminostilbene-based compound having at least one sulfonic acid group in a molecule. These compounds also have an effect of promoting the elution of the sensitizing dye out of the light-sensitive material, and are therefore preferable. Another preferred embodiment is a solid particulate compound having a fluorescent whitening effect.

  The silver halide light-sensitive material according to the present invention has a layer containing a silver halide emulsion spectrally sensitized to a specific region in a wavelength region of 400 to 900 nm. The silver halide emulsion contains one kind or a combination of two or more kinds of sensitizing dyes.

  As the spectral sensitizing dye used in the silver halide emulsion used in the present invention, any known compounds can be used. Examples of the blue sensitizing dye include those described in JP-A-3-251840, page 28. BS-1 to BS-8 can be preferably used alone or in combination. As the green photosensitive sensitizing dye, GS-1 to GS-5 described on page 28 of the same publication are preferably used. As the red-sensitive sensitizing dye, RS-1 to 8 described on page 29 of the same publication are preferably used.

  These sensitizing dyes may be added at any time from the formation of silver halide grains to the end of chemical sensitization. In addition, as a method for adding these dyes, water or an organic solvent miscible with water such as methanol, ethanol, fluorinated alcohol, acetone, and dimethylformamide may be dissolved and added as a solution. May be added as a solution, emulsion or suspension in a water-miscible solvent having a density of more than 1.0 g / ml.

As a method of dispersing the sensitizing dye, a method of mechanically pulverizing and dispersing the sensitizing dye into fine particles having a particle size of 1 μm or less in an aqueous system using a high-speed stirring dispersing machine may be used, as described in JP-A-58-105141. 8, a method of mechanically pulverizing and dispersing into fine particles of 1 μm or less in an aqueous system at 60 to 80 ° C., the surface tension described in JP-B-60-6496 being 3.8 × 10 ⁻² N / m or less A method of dispersing in the presence of a surfactant suppressed to a level described in JP-A-50-80826, which is substantially free of water and dissolved in an acid having a pKa of not more than 5, and adding the solution to an aqueous liquid A method of dispersing and adding this dispersion to a silver halide emulsion can be used.

  Water is preferable as a dispersion medium used for dispersion, but the solubility may be adjusted by adding a small amount of an organic solvent, or the stability of the dispersion may be increased by adding a hydrophilic colloid such as gelatin.

  Examples of the dispersing device that can be used to prepare the dispersion include a high-speed stirring type dispersing device shown in FIG. 1 of JP-A-4-125563, a ball mill, a sand mill, an ultrasonic dispersing device, and the like. be able to.

  When using these dispersing apparatuses, a method of performing a pre-treatment such as dry pulverization in advance and then performing a wet dispersing method as described in JP-A-4-125632 may be employed.

  The silver halide emulsion used in the present invention may contain one kind or a combination of two or more kinds of sensitizing dyes.

  As the coupler used in the silver halide light-sensitive material according to the present invention, any compound capable of forming a coupling product having a spectral absorption maximum wavelength in a wavelength region longer than 340 nm by coupling reaction with an oxidized form of a color developing agent is used. Although it is also possible to use, particularly typical examples include a yellow dye-forming coupler having a spectral absorption maximum wavelength in a wavelength range of 350 to 500 nm, a magenta dye-forming coupler having a spectral absorption maximum wavelength in a wavelength range of 500 to 600 nm, Typical examples are cyan dye-forming couplers having a spectral absorption maximum wavelength in a wavelength range of 600 to 750 nm.

  As the magenta coupler used in the silver halide light-sensitive material according to the present invention, a compound represented by the following formula (EXM) is preferable because of its excellent color development and excellent image stability.

Wherein, R _M represents optionally may secondary or tertiary alkyl group having a substituent Y represents a group that splits off by the coupling.

R _M is preferably a secondary alkyl group, particularly preferably an isopropyl group having a substituent at the 2-position. As the substituent at the 2-position of the isopropyl group, those in which a diffusion-resistant group is bonded via a carboamide group, a sulfamide group, or an oxycarbonyl group are preferable.

  The group which can be eliminated upon coupling with the oxidized form of the color developing agent represented by Y is not particularly limited, and includes, for example, a halogen atom, an alkoxy group, an aryloxy group, a heterocyclic oxy group, an alkylthio group, an arylthio group. Group, carbonyloxy group, cyano group and the like. It is preferably a halogen atom, and more preferably a chlorine atom.

  Specific examples of preferred compounds are shown below, but the present invention is not limited thereto.

  Among them, the compounds represented by EXM-1 and EXM-3 are preferable because their spectral absorption characteristics are suitable for proof use. It is known that the spectral absorption characteristics and image stability are affected by the type of the high boiling organic solvent, the mass ratio of the high boiling organic solvent to the coupler, and the like. Phosphate esters are preferred as the high boiling point organic solvent, and examples thereof include tricresyl phosphate, tri (2-ethylhexyl) phosphate, trioctyl phosphate, and trihexyl phosphate. Among them, aliphatic phosphate esters are preferred. The mass ratio of the high boiling point solvent to the coupler is preferably from 6: 1 to 1: 1 and more preferably from 4: 1 to 2: 1.

The magenta coupler can be used in combination with other types of magenta couplers, and is usually 1 × 10 ^-3 mol to 1 mol, preferably 1 × 10 ^-2 mol to 8 × 10 ^-1 mol, per mol of silver halide. Can be used in a range.

  [Lambda] max of the spectral absorption of the magenta image formed in the photosensitive material according to the present invention is preferably 530 to 560 nm, and [lambda] L0.2 is preferably 580 to 635 nm. λL0.2 is a wavelength longer than the wavelength at which the maximum absorbance shows 1.0 and the wavelength at which the absorbance shows 0.2 on the spectral absorbance curve of the magenta image.

  The magenta image forming layer of the silver halide light-sensitive material according to the present invention preferably contains a yellow coupler in addition to the magenta coupler. The difference in pKa between these couplers is preferably within 2 and more preferably within 1.5. Preferred yellow couplers to be contained in the magenta image-forming layer of the present invention are couplers represented by the general formula [Y-Ia] described in JP-A-6-95283, page 12, right column. Among the couplers represented by the general formula [Y-1] of the same publication, particularly preferred are couplers represented by the general formula [M-1] when combined with the magenta coupler represented by the general formula [M-1]. Is a coupler having a pKa value not lower than 3 or lower than a pKa lower than 3 pKa.

  Specific examples of the yellow coupler include compounds Y-1 and Y-2 described on pages 12 to 13 of JP-A-6-95283, and compounds described on pages 13 to 17 of JP-A-2-139542 ( Y-1) to (Y-58) can be preferably used, but are not limited thereto.

    One of the features of the present invention is that a cyan image forming silver halide emulsion layer contains at least one compound represented by the above general formula (I) or (II). Although this coupler is known to exhibit excellent characteristics in reproducing C and green, it is found that the fluctuation of the color tone caused by the change of the dot percentage such as the black dot is rather large. Was. The present invention is effective in obtaining the effect of excellent color reproducibility, and the use of these couplers is a preferred embodiment of the present invention.

  The compound represented by Formula (1) or Formula (2) will be described.

  The substituent having a substituent constant σp defined by Hammett of the cyan coupler of the present invention of +0.20 or more is specifically sulfonyl, sulfinyl, sulfonyloxy, sulfamoyl, phosphoryl, carbamoyl, acyl, acyloxy, oxycarbonyl, Examples include groups such as carboxyl, cyano, nitro, halogen-substituted alkoxy, halogen-substituted aryloxy, pyrrolyl, and tetrazolyl, and halogen atoms.

  Sulfonyl groups include alkylsulfonyl, arylsulfonyl, halogen-substituted alkylsulfonyl, halogen-substituted arylsulfonyl and the like; sulfinyl groups include alkylsulfinyl and arylsulfinyl and the like; sulfonyloxy groups include alkylsulfonyloxy and arylsulfonyloxy; and sulfamoyl Groups include N, N-dialkylsulfamoyl, N, N-diarylsulfamoyl, N-alkyl-N-arylsulfamoyl and the like; phosphoryl groups include alkoxyphosphoryl, aryloxyphosphoryl, alkylphosphoryl, aryl Phosphoryl and the like; carbamoyl groups include N, N-dialkylcarbamoyl, N, N-diarylcarbamoyl, N-alkyl-N-arylcarbamoyl and the like; acyl As an acyloxy group, alkylcarbonyloxy, etc .; as an oxycarbonyl group, alkoxycarbonyl, aryloxycarbonyl, etc .; as a halogen-substituted alkoxy group, as α-halogen-substituted alkoxy, etc .; Examples of the aryloxy group include tetrafluoroaryloxy and pentafluoroaryloxy; and examples of the pyrrolyl group include 1-pyrrolyl; and examples of the tetrazolyl group include 1-tetrazolyl.

  In addition to the above substituents, a trifluoromethyl group, a heptafluoroisopropyl group, a nonylfluoro-t-butyl group, a tetrafluoroaryl group, a pentafluoroaryl group, and the like are also preferably used.

In the general formula (1), among the substituents represented by R ₁ or R ₂ , examples of the substituent other than the electron-withdrawing group include various ones and are not particularly limited. Aryl, anilino, acylamino, sulfonamide, alkylthio, arylthio, alkenyl, cycloalkyl, cycloalkenyl, alkynyl, heterocycle, alkoxy, aryloxy, heterocycleoxy, siloxy, amino, alkylamino, imide, ureido, sulfamoylamino , Alkoxycarbonylamino, aryloxycarbonylamino, alkoxycarbonyl, aryloxycarbonyl, heterocyclic thio, thioureido, hydroxyl and mercapto, spiro compound residue, bridged hydrocarbon compound residue and the like.

  The alkyl group preferably has 1 to 32 carbon atoms and may be linear or branched. As the aryl group, a phenyl group is preferable.

  Examples of the acylamino group include an alkylcarbonylamino group and an arylcarbonylamino group; examples of the sulfonamide group include an alkylsulfonylamino group and an arylsulfonylamino group; and the alkyl component and the aryl component of the alkylthio group and the arylthio group include the above-described alkyl groups and aryl groups. Can be

  The alkenyl group is preferably a group having 2 to 32 carbon atoms, and the cycloalkyl group is preferably a group having 3 to 12 carbon atoms, particularly 5 to 7 carbon atoms. The alkenyl group may be linear or branched. The cycloalkenyl group preferably has 3 to 12 carbon atoms, particularly preferably 5 to 7 carbon atoms.

  Examples of the ureido group include an alkylureido group and an arylureido group; and examples of the sulfamoylamino group include an alkylsulfamoylamino group and an arylsulfamoylamino group; and a heterocyclic group preferably having 5 to 7 members. Specifically, a 2-furyl group, a 2-thienyl group, a 2-pyrimidinyl group, a 2-benzothiazolyl group, and the like; a heterocyclic oxy group having a 5- to 7-membered heterocyclic ring is preferable. 6-tetrahydropyranyl-2-oxy group, 1-phenyltetrazol-5-oxy group, etc .; The heterocyclic thio group is preferably a 5- to 7-membered heterocyclic thio group, for example, 2-pyridylthio group, 2-benzothiathiol Zolylthio group, 2,4-diphenoxy-1,3,5-triazole-6-thio group and the like; siloxy groups include trimethylsiloxy group and triethyl Succinimide group, 3-heptadecylsuccinimide group, phthalimide group, glutarimide group, etc. as imide group; spiro [3.3] heptane-1- as spiro compound residue Yl and the like; bridged hydrocarbon compound residues include bicyclo [2.2.1] heptane-1-yl, tricyclo [3.3.1.13.7] decan-1-yl, and 7,7-dimethyl- Bicyclo [2.2.1] heptan-1-yl and the like.

  These groups may further contain a substituent such as a long-chain hydrocarbon group or a diffusion-resistant group such as a polymer residue.

In the general formula (1), examples of the group capable of leaving by reaction with the oxidized form of the color developing agent represented by X ₁ include, for example, a halogen atom (hydrochloric acid, bromine, fluorine, etc.), alkoxy, aryloxy, heterocyclic oxy, acyloxy , Sulfonyloxy, alkoxycarbonyloxy, aryloxycarbonyl, alkyloxalyloxy, alkoxyoxalyloxy, alkylthio, arylthio, heterocyclic thio, alkoxythiocarbonylthio, acylamino, sulfonamide, nitrogen-containing heterocyclic ring bonded with an N atom, Examples include groups such as alkoxycarbonylamino, aryloxycarbonylamino, and carboxyl. Of these, preferred are a hydrogen atom and a nitrogen-containing heterocyclic group bonded by an alkoxy, aryloxy, alkylthio, arylthio, or N atom. A.

In the general formula (1), examples of the nitrogen-containing 5-membered heterocyclic ring formed by Z ₁ include a pyrazole ring, an imidazole ring, a benzimidazole ring, a triazole ring, and a tetrazole ring.

  More specifically, the compound represented by the general formula (1) is represented by the following general formulas (1) -1 and (1) -2.

In the above general formula, at least one of R ₁ and R _{11 in} (1) -1 and at least one of R ₁ and R _{12 in} (1) -2 have a σp of 0.20 or more. It is an electron-withdrawing group.

X ₁ has the same meaning as X _{1 in} the general formula (1). In general formulas (1) -1 and (1) -2, among R ₁ and R _{11 to} R ₁₂ , σp is 0.20 or more. Are not a hydrogen atom or a substituent.

In the general formula (2), R ₃ and R ₄ represent an electron-withdrawing group having a Hammett's substituent constant σp of 0.20 or more, and these electron-withdrawing groups include R ₁ and R ₁ in the general formula (1). The same groups as the electron-withdrawing group for R ₂ can be exemplified. However, the sum of the σp values of R ₃ and R ₄ is 0.65 or more.

Examples of the nitrogen-containing 5-membered heterocyclic ring formed by Z ₂ include a pyrazole ring, an imidazole ring, and a tetrazole ring. These 5-membered nitrogen-containing heterocycles may have a substituent.

  More specifically, the compound represented by the general formula (2) is represented by the following general formulas (2) -1 and (2) -2.

In the formula, R ₃ , R ₄ and X ₂ have the same meanings as in the general formula (2). R ₂₁ represents a hydrogen atom or a substituent.

  Specific examples of the compound represented by formula (1) or (2) are shown below, but the invention is not limited thereto.

  In the invention in which the structure of the C coupler is not specified in the light-sensitive material according to the present invention, known phenol, naphthol or imidazole couplers can be used. For example, a phenol coupler substituted with an alkyl group, an acylamino group, or a ureido group, a naphthol coupler formed from a 5-aminonaphthol skeleton, a 2-equivalent naphthol coupler having an oxygen atom introduced as a leaving group, and the like are represented. You. Among these, preferred compounds include the general formulas [C-I] and [C-II] described on page 13 of JP-A-6-95283.

The cyan coupler can be used in the silver halide emulsion layer in an amount of 1 × 10 ^-3 to 1 mol, preferably 1 × 10 ^-2 to 8 × 10 ^-1 mol, per mol of silver halide.

  As the yellow coupler contained in the yellow image forming layer in the light-sensitive material according to the present invention, a known acylacetanilide-based coupler or the like can be preferably used.

  Specific examples of the yellow coupler include compounds described on pages 5 to 9 of JP-A-3-241345, compounds represented by Y-I-1 to Y-I-55, and JP-A-3-209466. And the compounds represented by Y-1 to Y-30 on pages 11 to 14 can also be preferably used. Further, couplers represented by general formula [Y-I] described in JP-A-6-95283, page 21, and compounds represented by general formulas (I) and (II) described in JP-A-2002-351223 can also be mentioned. .

  The λmax of the spectral absorption of the yellow image formed by the photosensitive material according to the present invention is preferably 425 nm or more, and λL0.2 is preferably 515 nm or less.

  The λL0.2 of the spectral absorption of the yellow image is a value defined by the contents described in JP-A-6-95283, page 21, right column, lines 1 to 24. Indicates the magnitude of unwanted absorption on the side.

The yellow coupler can be used in the silver halide emulsion layer in an amount of 1 × 10 ^-3 to 1 mol, preferably 1 × 10 ^-2 to 8 × 10 ^-1 mol, per mol of silver halide.

  In order to adjust the spectral absorption characteristics of the magenta image, the cyan image, and the yellow image, it is preferable to add a compound having a color tone adjusting action. As the compound for this, a phosphoric ester compound represented by the general formula [HBS-I] described on page 22 of JP-A-6-95283 and a phosphine oxide compound represented by [HBS-II] are preferable. Preferred are compounds represented by the general formula [HBS-II] described on page 22 of the same publication. Also, higher alcohol compounds represented by (ai) to (ax) described on page 5 of JP-A-4-265975 can be used.

  In the light-sensitive material according to the present invention, the silver halide emulsion layer is laminated and coated on a support, but the order from the support may be any order. In addition, an intermediate layer, a filter layer, a protective layer, and the like can be provided as necessary.

  An anti-fading agent can be used in combination with each of the magenta, cyan, and yellow couplers to prevent fading of the formed dye image due to light, heat, humidity, and the like. Preferred compounds include phenyl ether compounds represented by general formulas I and II on page 3 of JP-A-2-66541, phenol compounds represented by general formula IIIB described in JP-A-3-174150, and Amine compounds represented by the general formula A described in JP 90445 and metal complexes represented by the general formulas XII, XIII, XIV and XV described in JP-A-62-182741 are particularly preferable for magenta dyes. Compounds represented by the general formula I 'described in JP-A-1-19649 and compounds represented by the general formula II described in JP-A-5-11417 are particularly preferable for yellow and cyan dyes.

  When an oil-in-water emulsion dispersion method is used to add a stain inhibitor or other organic compound used in the silver halide light-sensitive material according to the present invention, a water-insoluble high-boiling organic compound having a boiling point of 150 ° C or higher is usually used. If necessary, a low-boiling point and / or water-soluble organic solvent is used in combination in the solvent, and the mixture is dissolved and emulsified and dispersed in a hydrophilic binder such as an aqueous gelatin solution using a surfactant. As a dispersing means, a stirrer, a homogenizer, a colloid mill, a flow jet mixer, an ultrasonic disperser or the like can be used. After or simultaneously with the dispersion, a step of removing the low boiling organic solvent may be added. As the high boiling point organic solvent that can be used for dissolving and dispersing the stain inhibitor and the like, phosphate esters such as tricresyl phosphate and trioctyl phosphate, and phosphine oxides such as trioctyl phosphine oxide are preferably used. Can be The high-boiling organic solvent preferably has a dielectric constant of 3.5 to 7.0. Two or more high boiling organic solvents can be used in combination.

  Preferred compounds as a surfactant used for dispersing a photographic additive used in the photosensitive material according to the present invention and adjusting a surface tension at the time of coating include a hydrophobic group having 8 to 30 carbon atoms in one molecule and a sulfone. Those containing an acid group or a salt thereof are mentioned. Specific examples include A-1 to A-11 described in JP-A-64-26854. Further, a surfactant in which a fluorine atom is substituted for an alkyl group is also preferably used. These dispersions are usually added to a coating solution containing a silver halide emulsion, and the time until the addition to the coating solution after the dispersion and the time from the addition to the coating after the addition to the coating solution are preferably as short as 10 hours each. Within 3 hours, more preferably within 20 minutes.

  In the silver halide light-sensitive material according to the present invention, a compound that reacts with an oxidized developing agent is added to a layer between the light-sensitive layers to prevent color turbidity or to a silver halide emulsion layer. It is preferable to improve fog and the like. The compound for this purpose is preferably a hydroquinone derivative, and more preferably a dialkylhydroquinone such as 2,5-di-t-octylhydroquinone. Particularly preferred compounds are those represented by the general formula II described in JP-A-4-133056, and include compounds II-1 to II-14 described on pages 13 to 14 and compound 1 described on page 17.

  It is preferable to add an ultraviolet absorber to the light-sensitive material according to the present invention to prevent static fog or improve the light fastness of a dye image. Preferable ultraviolet absorbers include benzotriazoles. Particularly preferred compounds are those represented by the general formula III-3 described in JP-A-1-250944 and those represented by the general formula III described in JP-A-64-66646. Compounds described in JP-A-63-187240, compounds represented by the general formula I described in JP-A-4-1633, compounds represented by the general formula (I) described in JP-A-5-165144, The compound shown by (II) is mentioned.

  It is preferable that the light-sensitive material according to the present invention contains an oil-soluble dye or pigment because whiteness is improved. Representative specific examples of oil-soluble dyes include compounds 1 to 27 described in JP-A-2-842, pp. 8-9.

  In the silver halide light-sensitive material according to the present invention, it is advantageous to use gelatin as a binder.If necessary, other gelatin, a gelatin derivative, a graft polymer of gelatin and another polymer, a protein other than gelatin, A hydrophilic colloid such as a sugar derivative, a cellulose derivative, or a synthetic hydrophilic polymer such as a homopolymer or a copolymer can also be used.

  As the hardener of these binders, it is preferable to use a vinyl sulfone hardener or a chlorotriazine hardener alone or in combination. It is preferable to use the compounds described in JP-A-61-249054 and JP-A-61-245153. Further, it is preferable to add a preservative and an antifungal agent as described in JP-A-3-157646 in the colloid layer in order to prevent the growth of mold and bacteria which adversely affect the photographic performance and image storability. It is preferable to add a slipping agent or matting agent described in JP-A-6-118543 or JP-A-2-73250 to the protective layer in order to improve the physical properties of the surface of the photosensitive material or the processed sample.

  As the support used in the photosensitive material according to the present invention, any material may be used, and paper coated with polyethylene or polyethylene terephthalate, a paper support made of natural pulp or synthetic pulp, a vinyl chloride sheet, a white pigment, Polypropylene, polyethylene terephthalate support, baryta paper and the like which may be contained can be used. Among them, a support having a water-resistant resin coating layer on both sides of the base paper is preferable. As the water-resistant resin, polyethylene, polyethylene terephthalate or a copolymer thereof is preferable.

As the support having a water-resistant resin coating layer on the surface of paper, a support having a smooth surface having a mass of 50 to 300 g / m ² is usually used, but for the purpose of obtaining a proof image, a feeling of handling is required. to approximate the printing paper, 130 g / m ² or less of the base paper is preferably used, it is preferably used further 70~120g / m ² base paper.

  The support used in the present invention can be preferably used regardless of whether it has random irregularities or is smooth.

  As the white pigment used for the support, an inorganic and / or organic white pigment can be used, and an inorganic white pigment is preferably used. For example, alkaline earth metal sulfates such as barium sulfate, alkaline earth metal carbonates such as calcium carbonate, fine silica powder, silica such as synthetic silicate, calcium silicate, alumina, alumina hydrate, oxidation Examples include titanium, zinc oxide, talc, and clay. The white pigment is preferably barium sulfate or titanium oxide.

  The amount of the white pigment contained in the water-resistant resin layer on the surface of the support is preferably 13% by mass or more, and more preferably 15% by mass, in order to improve sharpness.

  The degree of dispersion of the white pigment in the water-resistant resin layer of the paper support according to the present invention can be measured by the method described in JP-A-2-28640. When measured by this method, the degree of dispersion of the white pigment is preferably 0.20 or less, more preferably 0.15 or less, as the variation coefficient described in the above-mentioned publication.

  The resin layer of the paper support having a water-resistant resin layer on both sides used in the present invention may be a single layer or a plurality of layers. It is preferable to form a plurality of layers and to include a white pigment at a high concentration in contact with the emulsion layer, because sharpness is greatly improved and a proofing image is formed.

  Further, it is more preferable that the value of the center plane average roughness (SRa) of the support is 0.15 μm or less, and more preferably 0.12 μm or less, since the effect of good gloss is obtained.

  The photographic light-sensitive material used in the present invention may be subjected to corona discharge, ultraviolet irradiation, flame treatment, etc. on the support surface, if necessary, and then directly or undercoating (adhesion, antistatic property, It may be applied via one or more undercoat layers for improving degree stability, friction resistance, hardness, antihalation property, frictional properties and / or other properties.

  When coating a photographic light-sensitive material using a silver halide emulsion, a thickener may be used to improve coatability. Extrusion coating and curtain coating, in which two or more layers can be applied simultaneously, are particularly useful as a coating method.

  As the width of the photosensitive material, any width can be used depending on the application, but a width of 400 mm or more is preferably used for proof use. A photosensitive material having a width of 800 mm or more is also preferably used.

  As the exposure light source of the exposure apparatus used in the present invention, any known light source can be preferably used, but a laser or a light emitting diode (hereinafter, referred to as LED) is more preferably used.

  As a laser, a semiconductor laser (hereinafter, referred to as an LD) is preferably used because it is compact and the life of the light source is long. In addition, LDs are used for applications such as optical pickups for DVDs and music CDs, barcode scanners for POS systems, and for applications such as optical communication, and have the advantage of being inexpensive and having a relatively high output. have. Specific examples of LD include aluminum gallium indium arsenide (650 nm), indium gallium phosphorus (up to 700 nm), gallium arsenic phosphorus (610 to 900 nm), and gallium aluminum arsenide (760 to 850 nm). ) And the like. Recently, a laser emitting blue light has been developed, but at present, it is advantageous to use an LD as a light source having a longer wavelength than 610 nm.

  As a laser light source having an SHG element, light emitted from an LD or YAG laser is converted into half-wavelength light by the SHG element and emitted. Since a visible light is obtained, there is no green light source. Used as a light source in the blue region. As an example of this type of light source, there is a combination of a YAG laser and an SHG element (532 nm).

  Examples of the gas laser include a helium-cadmium laser (about 442 nm), an argon ion laser (about 514 nm), and a helium neon laser (about 544 nm and 633 nm).

  As an LED, an LED having a composition similar to that of an LD is known, but various LEDs from blue to infrared have been put to practical use. An edge-emitting diode, which is a kind of small-area light-emitting diode described in JP-A-2002-72367, can be preferably used.

  As an exposure light source used in the present invention, each laser may be used alone, or a combination thereof may be used as a multi-beam. In the case of an LD, for example, by arranging ten LDs, a beam composed of ten light beams can be obtained. On the other hand, in the case of a helium neon laser, the light emitted from the laser is split into, for example, ten light beams by a beam separator.

  In the case of an LD or LED, the intensity of the exposure light source can be directly modulated by changing the value of the current flowing through each element. In the case of direct modulation, the amount of emitted light may be changed by adjusting the current value, or a pulse width modulation method may be used in which light is emitted in a pulse shape and the pulse width (emission time) is changed. A pulse number modulation method of changing the number may be employed. In the case of an LD, the intensity may be changed using an element such as an AOM (acousto-optic modulator). In the case of a gas laser, a device such as an AOM or an EOM (electro-optic modulator) is generally used.

  When an LED is used as a light source, a method may be used in which the same pixel is repeatedly exposed by a plurality of elements as long as the amount of light is weak.

  The emission wavelength of the light source can be preferably used as long as the photosensitive material has a sufficient sensitivity in a wavelength range, but a wavelength range having a sufficient sensitivity difference from other photosensitive layers in the sense of preventing color turbidity can be used. Preferably, it is used. Although it depends on the contrast of the photosensitive material, there is preferably a sensitivity difference of 0.6 or more, preferably 1.0 or more as a common logarithm of the exposure amount. In addition, if the emission wavelength fluctuates due to the environmental conditions, operating conditions, etc. where the light source is placed, it is theoretically preferable to adjust the wavelength to the peak wavelength of the spectral sensitivity. It is preferable to select the wavelength in consideration of the relationship with the wavelength. Such examples include JP-A-6-75342 and JP-A-2001-83663. Even when the emission intensity fluctuates in addition to the emission wavelength, it is preferable to select the emission wavelength in relation to the spectral sensitivity. For example, Japanese Patent Application Laid-Open No. 2002-72367 and Nikkei New Materials 1987 It is described on page 54 of the issue of March 14th.

  As a device used for image formation, a method in which a plurality of photosensitive materials are set in advance and a photosensitive material is appropriately selected and used can be preferably used. In this case, the two types of photosensitive materials may be, for example, photosensitive materials having different widths or photosensitive materials having different surface qualities (unevenness of the support). The selection of the photosensitive material may be performed by a method of setting with a switch or the like of the image forming apparatus, or may be performed based on the setting information transmitted with the image data. It is also advantageous to automatically select the optimal size of the photosensitive material according to the size of the image data. In special cases, the same type of photosensitive material can be loaded, and when one photosensitive material is used up, the other photosensitive material can be used automatically, which makes continuous unattended operation possible. Can be used.

  In the present invention, the term "area gradation image" is used. However, this is not expressed by shading on the image by the shading of the color of each pixel, but by the size of the area of a portion colored to a specific density. This is equivalent to a dot.

  In the case of normal area gradation exposure, the purpose can be achieved by developing Y, M, C, and black. More preferably, in order to identify that a single color such as M or C has developed in addition to black, it is preferable to use three or more different exposure amounts for exposure. In printing, a plate of a special color may be used, but in order to reproduce this, it is preferable to use four or more values of exposure for different exposures.

  In the case of a laser light source, the beam diameter is preferably 25 μm or less, more preferably 6 to 22 μm. Although smaller than 6 μm is preferable in terms of image quality, adjustment is difficult and processing speed is reduced. On the other hand, if it is larger than 25 μm, the unevenness increases and the sharpness of the image deteriorates. By optimizing the beam diameter, writing of a high-definition image without unevenness can be performed at high speed.

  To draw an image with such light, it is necessary for the light beam to scan over the silver halide photosensitive material.However, the photosensitive material is wound around a cylindrical drum and rotated at high speed in a direction perpendicular to the rotation direction. A cylindrical outer surface scanning method in which a light beam is moved may be used, and a cylindrical inner surface scanning method in which a silver halide photosensitive material is brought into close contact with a cylindrical recess and exposed is preferably used. A plane scanning method may be adopted in which the polyhedral mirror is rotated at a high speed and the silver halide light-sensitive material conveyed thereby is exposed by moving a light beam at right angles to the conveying direction. In order to obtain a high quality and large image, a cylindrical outer surface scanning method is more preferably used.

  In order to perform exposure by the cylindrical outer surface scanning method, the silver halide photosensitive material must be accurately brought into close contact with a cylindrical drum. In order for this to be performed properly, it is necessary that the wafer be transported while being accurately aligned. The silver halide light-sensitive material used in the present invention is preferably used when the surface on the side to be exposed is rolled outward, so that the alignment can be more accurately performed. From the same viewpoint, the support used for the silver halide light-sensitive material used in the present invention has appropriate rigidity, and preferably has a Taber rigidity of 0.8 to 4.0.

  The drum diameter can be arbitrarily set in accordance with the size of the silver halide photosensitive material to be exposed. The number of rotations of the drum can be set arbitrarily, but an appropriate number of rotations can be selected according to the beam diameter of the laser beam, the energy intensity, the writing pattern, the sensitivity of the photosensitive material, and the like. From the viewpoint of productivity, it is preferable that scanning exposure can be performed at higher rotation speed, but specifically, 200 to 3000 rotations per minute is preferably used.

  The method of fixing the silver halide photosensitive material to the drum may be fixed by mechanical means, or a large number of fine holes that can be sucked on the drum surface are provided according to the size of the photosensitive material, and the photosensitive material is fixed. It can also be brought into close contact by suction. It is important to make the photosensitive material as close as possible to the drum in order to prevent troubles such as uneven images.

Known compounds can be used as the aromatic primary amine developing agent used in the present invention. The following compounds can be mentioned as examples of these compounds.
CD-1) N, N-diethyl-p-phenylenediamine CD-2) 2-amino-5-diethylaminotoluene CD-3) 2-amino-5- (N-ethyl-N-laurylamino) toluene CD-4 ) 4- (N-Ethyl-N- (β-hydroxyethyl) amino) aniline CD-5) 2-Methyl-4- (N-ethyl-N- (β-hydroxyethyl) amino) aniline CD-6) 4 -Amino-3-methyl-N-ethyl-N- (β- (methanesulfonamido) ethyl) -aniline CD-7) N- (2-amino-5-diethylaminophenylethyl) methanesulfonamide CD-8) N , N-Dimethyl-p-phenylenediamine CD-9) 4-Amino-3-methyl-N-ethyl-N-methoxyethylaniline CD-10) 4-Amino-3-methyl-N -Ethyl-N- (β-ethoxyethyl) aniline CD-11) 4-Amino-3-methyl-N-ethyl-N- (γ-hydroxypropyl) aniline In the present invention, the above-described color developing agent is optional. Although it can be used in the pH range, it is preferably in the range of pH 9.5 to 13.0 from the viewpoint of rapid processing, and more preferably in the range of pH 9.8 to 12.0.

  The processing temperature of color development according to the present invention is preferably 35 ° C. or more and 70 ° C. or less. The higher the temperature, the shorter the processing time is possible, which is preferable. However, from the viewpoint of the stability of the processing solution, the higher the temperature, the more preferable.

  Conventionally, the color development time is generally about 3 minutes and 30 seconds, but in the present invention, it is preferably within 40 seconds, and more preferably within 25 seconds.

  A known developer component compound can be added to the color developing solution in addition to the above color developing agent. Usually, an alkali agent having a pH buffering action, a chloride ion, a development inhibitor such as benzotriazoles, a preservative, a chelating agent and the like are used.

  The silver halide light-sensitive material of the present invention is subjected to bleaching and fixing after color development. The bleaching process may be performed simultaneously with the fixing process. After the fixing process, a washing process is usually performed. Further, as an alternative to the water washing treatment, a stabilization treatment may be performed. The developing apparatus used for developing the silver halide photosensitive material of the present invention is a roller transport type in which the photosensitive material is conveyed between rollers arranged in a processing tank, and the photosensitive material is fixed to a belt. An endless belt method may be used, in which the processing tank is formed in a slit shape, and a processing liquid is supplied to this processing tank and the photosensitive material is transported, or a spray method in which the processing liquid is sprayed Alternatively, a web method by contact with a carrier impregnated with a treatment liquid, a method using a viscous treatment liquid, and the like can be used. When processing in large quantities, it is usual to perform a running process using an automatic developing machine, but at this time, the smaller the replenishment amount of the replenisher is, the more preferable it is. And the method described in JP-A-94-16935 is most preferable.

Hereinafter, preferred embodiments of the present invention will be described, but the present invention is not limited thereto.
(1) In an area gradation image forming method having means for controlling dot density and dot gain independently, a change in dot gain with respect to a change in density of a magenta image is 10 to 30 at 30% of dot%. Characteristic area gradation image forming method.
(2) In an area gradation image forming method having means for controlling dot density and dot gain independently, a change in dot gain with respect to a change in density of a magenta image is 15 to 28 at 30% of dot%. Characteristic area gradation image forming method.
(3) In the area gradation image forming method having means for independently controlling the halftone dot density and the dot gain, the change in dot gain with respect to the change in density of the magenta image is 20 to 25 at 30% of halftone%. Characteristic area gradation image forming method.
(4) In the relationship between the density of the magenta image and the dot gain, the above equation (1) is obtained at five equally spaced points between halftone dot density-0.1 to halftone dot density + 0.1 in the black plate or special color plate. (1) to (3), wherein the GOF value obtained by (1) is 1 or less.
(5) In the relationship between the density of the magenta image and the dot gain, the above equation (1) is obtained at five equally spaced points between the halftone dot density−0.1 and the halftone dot density + 0.1 in the black plate or the special color plate. (1) to (3), wherein the GOF value obtained by the above is 0.8 or less.
(6) In the relationship between the density of the magenta image and the dot gain, the above equation (1) is obtained at five equally spaced points between the halftone dot density -0.1 and the halftone dot density +0.1 in the black plate or special color plate. (1) to (3), wherein the GOF value obtained by (1) is 0.5 or less.
(7) In the relationship between the density of the magenta image and the dot gain, the above equation (1) is obtained at five points equally spaced between halftone dot density−0.2 to halftone dot density + 0.2 in the black plate or special color plate. (1) to (3), wherein the GOF value obtained by (1) is 1 or less.
(8) In the area gradation image forming method having means for independently controlling the dot density and the dot gain, a change in the dot gain with respect to a change in the density of the cyan image is 5 to 25 at 30% of the dot%. Characteristic area gradation image forming method.
(9) In the area gradation image forming method having means for independently controlling the dot density and the dot gain, the change in dot gain with respect to the change in density of the cyan image is 10 to 22 at 30% of the dot%. Characteristic area gradation image forming method.
(10) In the area gradation image forming method having means for independently controlling the halftone dot density and the dot gain, a change in dot gain with respect to a change in density of the cyan image is 15 to 20 at 30% of halftone%. Characteristic area gradation image forming method.
(11) In the area gradation image forming method, at least one kind of silver halide photosensitive material containing a cyan coupler represented by the general formula (I) is used. The area gradation image forming method described in the above.
(12) The method for forming an area gradation image according to (8) to (10), wherein a silver halide photosensitive material containing at least one cyan coupler represented by the general formula (II) is used. The area gradation image forming method described in the above.
(13) In the area gradation image forming method, at least one layer containing 35% by mass or more of a white pigment is provided between the support and the silver halide emulsion layer closest to the support. The area gradation image forming method according to any one of (1) to (12).
(14) In the area gradation image forming method, at least one layer containing 40% by mass or more of a white pigment is provided between the support and the silver halide emulsion layer closest to the support. The area gradation image forming method according to any one of (1) to (12).
(15) In the area gradation image forming method, at least one layer containing 60% by mass or more of a white pigment is provided between the support and the silver halide emulsion layer closest to the support. The area gradation image forming method according to any one of (1) to (12).
(16) In the area gradation image forming method, the white pigment contained between the support and the silver halide emulsion layer closest to the support is rutile-type titanium dioxide. (15) The method for forming an area gradation image according to any one of the above (15).

  Hereinafter, the present invention will be described in detail with reference to examples, but embodiments of the present invention are not limited thereto.

Example 1
A high-density polyethylene on one side and a fused polyethylene containing anatase-type titanium oxide dispersed at a content of 15% by mass on the other side, a polyethylene-laminated paper reflective support having a mass per square meter of 115 g (Taber stiffness) = 3.5, PY value = 2.7 μm), and the layers having the layer constitutions shown in Tables 1 and 2 below were applied on the side of the polyethylene layer containing titanium oxide, and 6.00 g of gelatin was further applied on the back side. / M ² and 0.65 g / m ^{2 of} a silica matting agent. 101 was produced.

The coupler was dissolved in a high-boiling-point solvent, ultrasonically dispersed, and added as a dispersion. At this time, (SU-1) was used as a surfactant. (H-1) and (H-2) were added as hardeners. Surfactants (SU-2) and (SU-3) were added as coating aids to adjust the surface tension. Further, (F-1) was added to each layer so that the total amount was 0.04 g / m ² .

SU-1: sodium tri-i-propylnaphthalenesulfonate SU-2: di (2-ethylhexyl) sulfosuccinate sodium salt SU-3: di (2,2,3,3,4,4, sulfosuccinate) 5,5-octafluoropentyl) sodium salt H-1: tetrakis (vinylsulfonylmethyl) methane H-2: 2,4-dichloro-6-hydroxy-s-triazine sodium HQ-1: 2,5-di t-octylhydroquinone HQ-2: 2,5-di ((1,1-dimethyl-4-hexyloxycarbonyl) butyl) hydroquinone HQ-3: 2,5-di-sec-dodecylhydroquinone and 2,5-di -Sec tetradecyl hydroquinone and 2-sec-dodecyl-5-sec-tetradecyl hydroquinone in a mass ratio of 1: 1: 2 SO-1: trioctyl phosphine oxide SO-2: di (i-decyl) phthalate SO-3: oleyl alcohol SO-4: tricresyl phosphate PVP: polyvinylpyrrolidone

(Preparation of blue-sensitive silver halide emulsion)
The following (Solution A) and (Solution B) were simultaneously added to 1 liter of a 2% aqueous gelatin solution kept at 40 ° C. while controlling pAg = 7.3 and pH = 3.0, and the following (Solution C) and (Solution D) was added simultaneously while controlling pAg = 8.0 and pH = 5.5. At this time, the pAg was controlled by the method described in JP-A-59-45437, and the pH was controlled using sulfuric acid or an aqueous sodium hydroxide solution.
(A liquid)
3.42 g of sodium chloride
Potassium bromide 0.03g
200 ml with water
(B liquid)
Silver nitrate 10g
200 ml with water
(Liquid C)
Sodium chloride 102.7g
Potassium hexachloroiridate (IV) 4 × 10 ^-8 mol Potassium hexacyanoferrate (II) 2 × 10 ^-5 mol Potassium bromide 1.0 g
600 ml with water
(D liquid)
Silver nitrate 300g
600 ml with water
After completion of the addition, desalting was carried out using a 5% aqueous solution of Demol N and 20% aqueous solution of magnesium sulfate manufactured by Kao Atlas Co., Ltd. A monodispersed cubic emulsion EMP-101 having a silver chloride content of 0.07 and a silver chloride content of 99.5 mol% was obtained.

  The above (EMP-101) was optimally chemically sensitized at 60 ° C. using the following compound to obtain a blue-sensitive silver halide emulsion (Em-B101).

Sodium thiosulfate 0.8mg / mol AgX
Chloroauric acid 0.5mg / mol AgX
Stabilizer STAB-1 3 × 10 ^-4 mol / mol AgX
Stabilizer STAB-2 3 × 10 ^-4 mol / mol AgX
Stabilizer STAB-3 3 × 10 ^-4 mol / mol AgX
Sensitizing dye BS-1 4 × 10 ^-4 mol / mol AgX
Sensitizing dye BS-2 1 × 10 ^-4 mol / mol AgX
Potassium bromide 0.2g / mol AgX
Next, in the preparation of EMP-101, the average particle size was adjusted in the same manner as in EMP-101 except that the addition time of (Solution A) and (Solution B) and the addition time of (Solution C) and (Solution D) were changed. A monodispersed cubic emulsion EMP-102 having a particle size distribution of 64 μm, a coefficient of variation of 0.07 and a silver chloride content of 99.5 mol% was obtained. Em-B102 was obtained in the same manner as in the preparation of Em-B101 except that EMP-102 was used instead of EMP-101, and a 1: 1 mixture of Em-B101 and 102 was used as a blue-sensitive emulsion.

(Preparation of green photosensitive silver halide emulsion)
In the preparation of EMP-101, the average particle diameter was 0.40 μm, the coefficient of variation was 0.08, and the A monodispersed cubic emulsion (EMP-103) having a silver content of 99.5% was obtained.

  The above-mentioned EMP-102 was optimally chemically sensitized at 55 ° C. using the following compounds to obtain a green-sensitive silver halide emulsion (Em-G101).

Sodium thiosulfate 1.5mg / mol AgX
Chloroauric acid 1.0mg / mol AgX
Stabilizer STAB-1 3 × 10 ^-4 mol / mol AgX
Stabilizer STAB-2 3 × 10 ^-4 mol / mol AgX
Stabilizer STAB-3 3 × 10 ^-4 mol / mol AgX
Sensitizing dye GS-1 2 × 10 ^-4 mol / mol AgX
Sensitizing dye GS-2 2 × 10 ^-4 mol / mol AgX
Sodium chloride 0.5g / mol AgX
Next, in the preparation of EMP-103, the average particle size was adjusted in the same manner as EMP-103 except that the addition time of (Solution A) and (Solution B) and the addition time of (Solution C) and (Solution D) were changed. A monodispersed cubic emulsion EMP-104 having a thickness of 50 µm, a coefficient of variation of 0.08 and a silver chloride content of 99.5% was obtained. Em-G102 was obtained in the same manner as Em-G101 except that EMP-104 was used in place of EMP-103, and a 1: 1 mixture of Em-G101 and 102 was used as a green photosensitive emulsion.

(Preparation of red-sensitive silver halide emulsion)
The EMP-103 was optimally chemically sensitized at 60 ° C. using the following compounds to obtain a red-sensitive silver halide emulsion (Em-R101).

Sodium thiosulfate 1.8mg / mol AgX
Chloroauric acid 2.0mg / mol AgX
Stabilizer STAB-1 2 × 10 ^-4 mol / mol AgX
Stabilizer STAB-2 2 × 10 ^-4 mol / mol AgX
Stabilizer STAB-3 2 × 10 ^-4 mol / mol AgX
Stabilizer STAB-4 1 × 10 ^-4 mol / mol AgX
Sensitizing dye RS-1 1 × 10 ^-4 mol / mol AgX
Sensitizing dye RS-2 1 × 10 ^-4 mol / mol AgX
Supersensitizer SS-1 2 × 10 ^-4 mol / mol AgX
Next, in the preparation of (Em-R101), the following compounds were optimally subjected to chemical sensitization at 60 ° C. to obtain a red-sensitive silver halide emulsion (Em-R102).

Sodium thiosulfate 1.8mg / mol AgX
Chloroauric acid 2.0mg / mol AgX
Stabilizer STAB-1 2 × 10 ^-4 mol / mol AgX
Stabilizer STAB-2 2 × 10 ^-4 mol / mol AgX
Stabilizer STAB-3 2 × 10 ^-4 mol / mol AgX
Stabilizer STAB-4 1 × 10 ^-4 mol / mol AgX
Sensitizing dye RS-1 2 × 10 ^-4 mol / mol AgX
Sensitizing dye RS-2 2 × 10 ^-4 mol / mol AgX
Supersensitizer SS-1 2 × 10 ^-4 mol / mol AgX
A 1: 1 mixture of Em-R101 and Em-R102 was used as a red-sensitive emulsion.

STAB-1: 1-phenyl-5-mercaptotetrazole STAB-2: 1- (4-ethoxyphenyl) -5-mercaptotetrazole STAB-3: 1- (3-acetamidophenyl) -5-mercaptotetrazole STAB-4: p-toluenethiosulfonic acid

  By arranging ten B LEDs as a light source in the main scanning direction and delaying the timing of the exposure little by little, adjustment was made so that the same location could be exposed by the ten LEDs. Also, an exposure head was prepared in which ten LEDs were arranged in the sub-scanning direction, and exposure for ten adjacent pixels could be performed at one time. For G and R, exposure heads were prepared by combining LEDs in the same manner. The diameter of each beam was about 10 μm, the beams were arranged at this interval, and the sub-scanning pitch was about 100 μm. The exposure time per pixel was about 100 nanoseconds.

  First, a solid exposure sample in which the amount of R light was changed at a preset exposure amount was prepared, and a sample in which the amount of R light was similarly changed at 30% of the halftone dot was prepared. After exposure, the following development treatment was performed to obtain a dye image. The B, G, and R concentrations were measured.

Processing process Processing temperature Time Replenishment amount Color development 33.0 ± 0.3 ℃ 120 seconds 80ml
Bleaching and fixing 33.0 ± 0.5 ° C 90 seconds 120ml
Stabilization 30-34 ° C 60 seconds 150ml
Drying 60-80 ° C for 30 seconds Color developer tank solution and replenisher tank solution Replenisher Pure water 800ml 800ml
Triethylenediamine 2g 3g
Diethylene glycol 10g 10g
Potassium bromide 0.01 g −
3.5 g of potassium chloride-
Potassium sulfite 0.25g 0.5g
N-ethyl-N- (β-hydroxyethyl) -4-aminoaniline sulfate
2.9g 4.8g
N, N-disulfoethylhydroxylamine 20.4 g 18.0 g
Triethanolamine 10.0 g 10.0 g
Diethylenetriaminepentaacetic acid sodium salt 2.0g 2.0g
Fluorescent brightener (4,4'-diaminostilbene disulfonic acid derivative)
2.0g 2.5g
Potassium carbonate 30g 30g
The total volume is adjusted to 1 liter by adding water, and the tank solution is adjusted to pH = 10.0 and the replenisher is adjusted to pH = 10.6.

Bleach-fixer tank solution and replenisher Ferric ammonium diethylenetriaminepentaacetate dihydrate 65g
3 g of diethylenetriaminepentaacetic acid
Ammonium thiosulfate (70% aqueous solution) 100ml
2-amino-5-mercapto-1,3,4-thiadiazole 2.0 g
Ammonium sulfite (40% aqueous solution) 27.5ml
Water was added to make the total volume 1 liter, and the pH was adjusted to 5.0 with potassium carbonate or glacial acetic acid.

Stabilizing solution tank solution and replenisher solution o-phenylphenol 1.0 g
5-chloro-2-methyl-4-isothiazolin-3-one 0.02 g
2-methyl-4-isothiazolin-3-one 0.02 g
1.0 g of diethylene glycol
Optical brightener (Tinopearl SFP) 2.0g
1.8 g of 1-hydroxyethylidene-1,1-diphosphonic acid
0.5 g of zinc sulfate
Magnesium sulfate heptahydrate 0.2g
PVP (polyvinyl pyrrolidone) 1.0 g
Aqueous ammonia (25% ammonium hydroxide aqueous solution) 2.5 g
Nitrilotriacetic acid trisodium salt 1.5g
The total volume is adjusted to 1 liter by adding water and adjusted to pH = 7.5 with sulfuric acid or aqueous ammonia.

  The G concentration of these samples was measured using a type 508 densitometer manufactured by X-Rite, and the horizontal axis was the density value of the solid sample, and the vertical axis was the dot gain (calculated by the Murray-Davis equation). ) Was taken and the measured values were plotted. At this time, the status T was used as the spectral characteristic. When the solid density was 1.45, the inclination of the tangent was found to be 8.3. When the GOF value was determined by equation 1 at five points in combination with the data of the solid density of 1.35, 1.40, 1.50, and 1.55, the value was 0.73.

Next, the sample no. In the same manner as in Sample No. 101 except that the coating amount of the third layer of No. 101 was variously changed. 102 to 105 were prepared, and the same evaluation was performed. Next, the light amount of the R light is fixed to the exposure amount necessary to obtain the solid density of 1.45, and the Y and C densities are variously changed so that the color tone of the black net of 50% of halftone is a ^* , b ^* was adjusted to be 1 and −1, respectively, and a 30% black net was produced under the conditions. At this time, the colorimetry was performed using a spectrophotometer CM-2022 manufactured by Minolta Co., and the light was measured using a geometric condition of illumination and light reception d-0 and a xenon pulse light source. The values of L ^* a ^* b ^* were determined, and the color difference between 50% and 30% of the black net was obtained. The color difference referred to here means a distance in the a ^* b ^* plane in the CIELAB color space. The results are shown in Table 3 below.

  By setting the coating amount of the third layer higher, the gradient of the tangent line at the density of 1.45 moves in a direction of decreasing, and the GOF value shows a behavior of decreasing. Sample No. In the case of No. 105, a behavior in which the dot gain increased on the high density side was observed, and it was found that the GOF value was increased due to this effect. It can be seen that all of the samples of the present invention have a small color difference due to the difference in halftone percentage. The value near the color difference of 2.0 is a value that is a boundary of whether or not the difference can be determined, and it can be seen that the effect of the present invention can be effectively obtained.

  Next, in the preparation of the third layer of Samples 101 to 105, EXM-1 was changed to 0.7 times in mole in place of magenta coupler M-1, and the high boiling organic solvent was replaced with tri (2-ethylhexyl) phosphate. Samples 111 to 115 were prepared in the same manner except that the mass of the coupler was added three times that of the coupler and the yellow coupler Y-2 was changed to an equimolar Y-1. As a result of the same evaluation, the following results were obtained.

  Thus, it was confirmed that the effects of the present invention can be similarly obtained even when the coupler and the high boiling point organic solvent are changed. When the same evaluation was performed for EXM-3, it was confirmed that the same effect was obtained. The samples using EXM-1 and EXM-3 have excellent red reproducibility and can reproduce brighter red than Samples 101 to 105. The use of the compound represented by the general formula (EXM) It has been found to be a preferred embodiment of the invention.

Example 2
Next, the sample No. of Example 1 was used. In the preparation of Sample No. 104, except for the colloidal silver and the antihalation dye (AI-4), Sample No. Sample No. 201 was prepared and combined with a change in the amount of titanium dioxide. 202-204 were prepared. The results of evaluation of this sample in the same manner as in Example 1 are shown in Table 5 below.

  It was confirmed that the effects of the present invention can be obtained in any of the samples in which the gradient at the concentration of 1.45 is within the range of the present invention. Increasing the content of titanium dioxide and increasing the content ratio shows a behavior of reducing the gradient of the tangent line, and it can be seen that it can be preferably used as a means for adjusting the gradient. From these results, it can be seen that 35 mass% is one criterion for the content of titanium dioxide, and it is easy to obtain preferable characteristics when the content is more than 35 mass%. Considering the results of Example 1, it is considered that mixing a coloring substance into the white pigment layer is also a preferable embodiment.

  Although the GOF value also changes depending on the amount of titanium dioxide, the value of the color difference falls to 1.5 when the GOF value becomes 1 or less, so that a visual effect can be obtained more than the numerical difference. Do you get it.

  The same evaluation was performed on a sample modified from the sample 114, and it was confirmed that the same effect can be obtained.

Example 3
Next, the same evaluation was performed using each sample of Example 2 while changing the exposure amount of G exposure. After setting the C is solid concentration of 1.45, M, to adjust the concentration of Y, the color tone of the dot percentage of 50% ^* net is a ^*, b ^* are respectively 1, adjusted to -1 Under these conditions, a 30% ink net was produced. The results are shown in Table 6 below. Regarding C, the same behavior as that of M was observed, and it was confirmed that the effect of the present invention was obtained.

  Next, the sample no. Samples 301 and 302 were prepared in the same manner as in preparing 101, except that the cyan coupler (C-11) was changed to equimolar C-12 and C-22, and a sample 303 was prepared using CC-1. Further, the sample No. Samples 311 and 312 were prepared in the same manner as in preparing 203, except that the cyan coupler (C-11) was changed to equimolar C-12 and C-22, and a sample 313 was prepared using CC-1. The same evaluation as in Example 1 was performed using this sample, and the results in Table 7 below were obtained.

  Even if the type of the C coupler is changed, the gradient of the tangent line at the density of 1.45 does not change much, and the GOF value does not change, but the color difference between the 30% and 50% of the halftone dot is CC-1. While C-11, 12, and 22 were relatively small, they were large. It is clear that there is a large difference between 101 and 301 to 303. On the other hand, it can be seen that the sample of the present invention is improved to such an extent that almost no difference is seen. Looking at the color reproduction, the samples using C-11, 12, and 22 were superior in reproducing C and green to the samples using CC-1, and the present invention compensated for the disadvantages of these couplers. This is a preferred embodiment of the present invention in that its effects are maximized.

Claims (5)

An area gradation image forming method having means for independently controlling halftone dot density and dot gain, wherein a change in dot gain with respect to a change in density of a magenta image is 10 to 30 at 30% of halftone dot. Area gradation image forming method. The relationship between the density of the magenta image and the dot gain was determined by the following equation 1 at five equally spaced points between the halftone dot density -0.1 and the halftone dot density +0.1 in the black plate or special color plate. 2. The area gradation image forming method according to claim 1, wherein the GOF value is 1 or less.
(Equation 1) GOF = {Σ (DG ai -DG ci) 2/4} 1/2
Wherein, DG _a represents the dot gain at each solid density, DG _c represents the value when computing the dot gain at each solid density by the following equation (2). i represents a data number and represents one of 1 to 5. ]
(Equation 2) DG _c = a × D + b
[Where D represents the solid density, and a and b both represent constants determined by the least squares method. ] An area gradation image forming method having means for independently controlling halftone dot density and dot gain, wherein a change in dot gain with respect to a change in density of a cyan image is 5 to 25 at 30% of halftone%. Area gradation image forming method. 4. The area gradation image forming method according to claim 3, wherein a silver halide photosensitive material containing at least one selected from cyan couplers represented by the following general formula (1) or (2) is used. Method.

[In the formula, R ₁ represents a hydrogen atom or a substituent, and R ₂ represents a substituent. m represents the number of substituents R ₂ . When m is 0, R ₁ represents an electron-withdrawing group having a Hammett's substituent constant σp of 0.20 or more. When m is 1 or 2 or more, at least one of R ₁ and R ₂ is substituted by Hammett. Represents an electron-withdrawing group having a group constant σp of 0.20 or more.
Z ₁ represents a nonmetallic atom group necessary to form a nitrogen-containing 5-membered heterocyclic ring which may be condensed with a benzene ring or the like.
R ₃ and R ₄ each represent an electron-withdrawing group having a Hammett's substituent constant σp of 0.20 or more. However, the sum of the σp values of R ₃ and R ₄ is 0.65 or more. Z ₂ represents a group of nonmetal atoms necessary for forming a nitrogen-containing 5-membered heterocyclic ring, and the 5-membered ring may have a substituent.
X ₁ and X ₂ each represent a hydrogen atom or a group which is released by a coupling reaction with an oxidized form of a color developing agent. ] 5. A silver halide photosensitive material having at least one layer containing 35% by mass or more of a white pigment between a support and a silver halide emulsion layer closest to the support. The method for forming an area gradation image according to any one of the above items.