JPH1199699A - Image recording method and apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively utilize the dynamic range of an external modulator having a narrow dynamic range by modulating a light beam with the external modulator and recording a step wedge pattern, measuring a plurality of obtained image concentrations, and selecting a driving current suitable for a recording material from a plurality of driving currents. SOLUTION: At the time of (re)setting command of the driving current of a light source using a semiconductor laser exciting solid laser, a setting means 90 forms a latent image of a step wedge pattern for each of a plurality of driving currents preliminarily determined, and it is visualized at a heat developing part. The light amount passed through a recording material A is measured by a sensor 84 so as to be transmitted to a setting means 90. Based on the passing light amount, the image density of the step wedge pattern is calculated. When the recording material A is a negative recording material, the minimum driving current when the step wedge pattern achieves a predetermined maximum density is set at a driver 92. When the recording material A is a positive recording material, the minimum driving current when the step wedge pattern achieves a predetermined minimum density is set as the driver 92.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention belongs to the technical field of image recording in which a semiconductor laser pumped solid-state laser is used as a light source and a light beam is modulated by an external modulator.

[0002]

2. Description of the Related Art Silver halide photographic light-sensitive materials, heat-developable light-sensitive materials, light- and heat-sensitive recording materials, electrophotographic light-sensitive materials, heat-sensitive recording materials, etc.
2. Description of the Related Art Image recording apparatuses that record images by scanning and exposing various recording materials with a light beam are widely used in various applications such as copying apparatuses and printers.

In these image recording apparatuses, in an image recording apparatus using a photosensitive recording material, for example, the recording material is scanned and exposed imagewise with a light beam having a wavelength corresponding to the spectral sensitivity characteristic of the recording material, and an image is formed. Recording and, if necessary, development processing according to the recording material to be used, for example, wet development processing using various processing solutions for silver salt photographic photosensitive materials, heat development for heat-developable photosensitive materials, etc. To produce a print on which a visible image (visible image) is recorded. On the other hand,
In an image recording apparatus using a heat-sensitive recording material, the heat-sensitive recording material is scanned and exposed imagewise using a light beam for heat recording, heated and colored to produce a print on which a visible image is recorded.

In the image recording by the light beam scanning, in the image recording by the direct modulation, the light beam is modulated in accordance with the recorded image by controlling the driving of the light beam light source. On the other hand, in the image recording by the indirect modulation, A light beam having a constant output emitted from the light beam light source is modulated by an external modulator such as an AOM (acousto-optic modulator), and the recording material is exposed imagewise. Among such image recording methods, an image recording method in which a semiconductor laser-excited solid-state laser is used as a light beam source and the light beam is modulated by an external modulator is known as a method capable of recording an image with a high-output light beam. .

[0005]

By the way, generally,
Even if a recording material can be used for the same image recording apparatus, its sensitivity (coloring) characteristics greatly differ depending on the type. Even for the same recording material, the sensitivity characteristics often differ between manufacturing lots, and further vary greatly with storage conditions and aging.

FIG. 5 is an example showing the relationship between the logarithm of the amount of exposure (log E) and the color density (D) in a certain photosensitive material. As is clear from this, even if the same material is used, the sensitivity is high. The photosensitive material A (solid line) having a high density and the photosensitive material B (dashed line) having a low sensitivity have a required density range (D _{min to} D).
_max ) is different as shown in a and b in the figure. Accordingly, in the image recording in which the light beam is modulated by the external modulator using the semiconductor laser-excited solid-state laser described above using the photosensitive material shown in FIG. In order to perform this, it is necessary to use an external modulator having a wide dynamic range, which can realize an exposure amount in a range C including the range a and the range b.

Therefore, in an image recording apparatus that modulates a light beam with an external modulator using a semiconductor laser pumped solid-state laser as a light source, an external modulator having a narrow dynamic range cannot be used, or an external modulator having a narrow dynamic range cannot be used. In an apparatus using a modulator, only a recording material having a relatively hard gradation characteristic (gamma is steep) and a narrow exposure area capable of developing _{Dmin to Dmax} can be used.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and to use a semiconductor laser-excited solid-state laser as a light beam light source, and to perform dynamic image recording in modulating the light beam with an external modulator. Even when an external modulator with a narrow range is used, the dynamic range can be effectively used, whereby even a recording material with a soft gradation, a wide density range can be appropriately colored, and a favorable It is an object of the present invention to provide an image recording method capable of performing image recording and an image recording apparatus using the image recording method.

[0009]

In order to achieve the above object, an image recording method according to the present invention comprises a method of scanning a recording material by exposing a recording material by modulating a light beam from a solid-state laser excited by a semiconductor laser with an external modulator. An image recording method for recording an image by driving the semiconductor laser-excited solid-state laser with a plurality of types of drive currents, modulating a light beam with the external modulator, and recording a step wedge pattern on a recording material. By measuring the image densities of the obtained plurality of step wedge patterns, from the plurality of drive currents, when the recording material is a negative recording material, the minimum value at which the step wedge pattern attains a predetermined maximum density is obtained. When the recording material is a positive recording material, the drive current is selected as the minimum drive current at which the step wedge pattern has achieved a predetermined minimum density, and this drive current is Serial to provide an image recording method and performing image recording as the laser-diode pumped solid-state laser drive current.

An image recording apparatus according to the present invention is an image recording apparatus for exposing a recording material with a light beam modulated in accordance with image data to record an image, wherein the semiconductor laser-excited solid-state device emits the light beam. A laser, a drive source for driving the semiconductor laser-pumped solid-state laser, a drive current variable, a modulator for modulating a light beam emitted from the semiconductor laser-pumped solid-state laser, and the modulator according to image data. Driving, recording control means having image data of a step wedge pattern, density measuring means for measuring the density of a recorded image, and image recording for driving a modulator according to the image data of the step wedge pattern by the recording control means. The semiconductor laser pumped solid-state laser is driven by a plurality of drive currents by the drive source, and the plurality of obtained scans are obtained. The concentration of-up wedge pattern measured by the density measuring device, from said plurality of kinds of driving current,
When the recording material is a negative recording material, the step wedge pattern has a minimum drive current at which a predetermined maximum density has been achieved, and when the recording material is a positive recording material, the step wedge pattern has a predetermined minimum density. An image recording apparatus, comprising: a driving current setting means for finding a minimum driving current achieved and setting the obtained driving current as a semiconductor laser-excited solid-state laser by the driving source.

Further, in the present invention, the recording material comprises latex at least 50% of a binder,
Organic silver salt, a recording material having an image forming layer containing an organic silver salt reducing agent, a thermoresponsive microcapsule containing an electron-donating colorless dye, an electron acceptor and a polymerizable vinyl monomer in the same molecule A recording material having an image forming layer containing a photopolymerization initiator, and a thermoresponsive microcapsule containing an electron-donating colorless dye, an electron-accepting compound, a polymerizable vinyl monomer, and a photopolymerization initiator. It is preferable that the recording material has at least one selected from three types of recording materials having an image forming layer.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an image recording method and an image recording apparatus according to the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

FIG. 1 is a schematic diagram showing an example of the image recording apparatus of the present invention for implementing the image recording method of the present invention. FIG.
The image recording device 10 shown in FIG. 1 is a device which is preferably used as a so-called medical imager for producing a print in which an image measured by a medical measuring instrument such as CT or MRI is reproduced as a visible image, and is transparent. Using a light-transmissive light- and heat-sensitive recording material A having a transparent film
A latent image is formed on the photosensitive and heat-sensitive recording material A by scanning exposure with a light beam L modulated according to image data supplied from an image data supply source R such as I, and then heat development is performed to record a visible image. Is a device that creates a printed image. Also,
In the image recording apparatus 10 according to the present invention, a semiconductor laser-excited solid-state laser is used as a light source of the light beam L, and the light beam L is modulated by external modulation to expose the light- and heat-sensitive recording material A.

The present invention is not limited to image recording using such a light- and heat-sensitive recording material A, but creates a print (hard copy) on which a visible image is recorded using various recording materials. It can be used for various types of image recording. Specific examples include a silver halide photographic light-sensitive material, an image-recording apparatus for obtaining a print by imagewise exposing the light-sensitive material and then performing wet development, and an image-receiving layer (dye-fixing layer) And the like, and an image recording apparatus using a heat-developable silver salt photosensitive material (Pictrographic photosensitive material manufactured by FUJIFILM Corporation) for transferring an image to an image receiving material having the property described above and printing the image.

In addition to the image recording apparatus using such a photosensitive material, the present invention uses a heat-sensitive recording material utilizing a high-power optical laser beam emitted by a semiconductor laser-excited solid-state laser, It can also be suitably used for an image recording apparatus (thermal recording apparatus) in which a thermosensitive recording material is imagewise heated by a laser beam (heat mode laser) to print a visible image. The heat-sensitive recording material is a known heat-sensitive material in which a heat-sensitive recording layer having a (heat-sensitive) color-forming layer that forms a color by heating a color developer and a developer that are isolated from each other at normal temperature is formed. The same may be used, as the color former and the developer, a combination of an electron-donating dye precursor and an electron-accepting compound,
Examples thereof include a combination of a photodegradable diazo compound and a coupler, and a combination of an organic metal salt such as silver behenate or silver stearate with a reducing agent such as protocatechinic acid.

The photosensitive and heat-sensitive recording material A used in the illustrated image recording apparatus 10 (hereinafter referred to as the recording apparatus 10) is not particularly limited, and various known photosensitive heat-developing (thermochromic) recording materials can be used. Although usable, the following materials are preferably exemplified as the light and heat sensitive recording material A particularly preferably used in the present invention.

First, a light- and heat-sensitive recording material (hereinafter, referred to as an image forming layer) having, on one surface of a support, an image forming layer in which 50% or more of a binder is composed of latex and contains an organic silver salt and a reducing agent of an organic silver salt. As the first recording material). In the first recording material, a photocatalyst such as photosensitive silver halide forms a latent image nucleus when exposed to light, and when heated, the silver of the organic silver salt ionized by the action of the reducing agent is formed. It moves and combines with the photosensitive silver halide to form crystalline silver, forming an image.

The organic silver salt contained in the image forming layer of the first recording material is relatively stable to light, but is exposed to a photocatalyst (such as a latent image of photosensitive silver halide) and a reducing agent. A silver salt that forms a silver image when heated to 80 ° C. or higher in the presence of, and may be desalted as necessary. Such organic silver salts include a silver salt of an organic acid, preferably a silver salt of a long-chain fatty carboxylic acid having 10 to 30 carbon atoms, and a complex stability constant having a ligand of 4.0 to 10.0. Complexes of organic or inorganic silver salts having, for example, silver behenate, silver arachidate, silver stearate, silver oleate, silver laurate, silver caproate, silver myristate, silver palmitate, maleate Silver acid, silver fumarate and the like are exemplified.

Further, as the organic silver salt, a silver salt of a compound containing a mercapto group or a thione group and derivatives thereof can be suitably used. Specifically, 3-mercapto-4-phenyl-1,2,3 Thioglycolic acid such as 2,4-triazole, 2-mercaptobenzimidazole, dithiocarboxylic acid such as dithioacetic acid, thioamide, 5-carboxyl-1-methyl-2-phenyl-4-thiopyridine, mercaptotriazine, 2-mercaptobenzoxazole And the like.

Such an organic silver salt is used to obtain polyacrylic acid,
It is preferable to use a known dispersant such as polyvinyl alcohol and polyvinylpyrrolidone to obtain a solid fine particle dispersion. The dispersion of the organic silver salt into solid fine particles may be performed by a known mechanical fine particle dispersion method using a ball mill, a vibration ball mill, or the like in the presence of a dispersant. In addition to the mechanical dispersion method, the pH may be controlled so that the particles are roughly dispersed in the solvent, and then the pH is changed in the presence of a dispersing agent to form fine particles.

The amount of the organic silver salt is 0.1 g / l to silver.
It is preferably 5 g / l, more preferably 1 g / l to 3 g / l.

The reducing agent for reducing such an organic silver salt is as follows:
Any substance that can reduce silver ions to metallic silver can be used, and is preferably an organic substance, such as organic silver disclosed in JP-A-6-3793 and US Pat. No. 5,464,738. Various known reducing agents used for light- and heat-sensitive recording materials using salts can be used. Specifically, bis (2-hydroxy-3-t-butyl-5-methylphenyl) methane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 4,4-ethylidene-bis (2 -T-butyl-6-methylphenol), 1,1-
Bis (2-hydroxy-3,5-dimethylphenyl)-
Suitable examples include bisphenols such as 3,5,5-trimethylhexane, chromanol, and hindered phenol reducing agents.

The reducing agent may be added by a method such as a solution, a powder, and a dispersion of solid fine particles. The amount of the reducing agent is preferably about 5 mol% to 50 mol% with respect to 1 mol of silver on the surface having the image forming layer. The reducing agent is basically added to the image forming layer, but may be used in other layers on the side having the image forming layer. In this case, it is necessary to use as much as 10 mol% to 50 mol% per 1 mol of silver. Is preferred. Further, the reducing agent may be a so-called precursor which is derivatized so as to have a function effectively only during development.

The image forming layer of the first recording material contains a substance which becomes a photocatalyst upon exposure, for example, photosensitive silver halide (hereinafter, referred to as silver halide). The halogen composition of the silver halide is not limited, and may be any of silver chloride, silver chlorobromide, silver bromide, silver iodobromide, silver iodochlorobromide, and silver iodide. And silver iodobromide are preferably used. The grain size of silver halide is 0.20μ
m or less. In order to suppress cloudiness after image formation, the particle size is preferably 0.20 μm or less, and particularly preferably cubic particles and tabular particles.

The silver halide grains include rhodium, rhenium, ruthenium, osnium, iridium, cobalt,
It is preferable that at least one complex of a metal selected from mercury or iron is contained in an amount of about 1 nmol to 10 mmol per 1 mol of silver. The silver halide grains are preferably chemically sensitized by a known method such as a sulfur sensitization method or a selenium sensitization method.

The amount of the silver halide used is preferably 0.01 mol to 0.5 mol per 1 mol of the organic silver salt.

In the first recording material, the image-forming layer having such a composition is prepared by dispersing a latex obtained by dispersing a water-insoluble hydrophobic polymer as fine particles in a water-soluble dispersion medium in an amount of 50 wt. % Or more. Alternatively, if necessary, other layers may have the same configuration. For such latex, see "Synthetic Resin Emulsion (edited by Tadashi Okuda and Hiroshi Inagaki, published by Kobunshi Kankokai (1
978))), “Applications of Synthetic Latex (Takaaki Sugimura, Yasuo Kataoka, Soichi Suzuki, Keiji Kasahara, edited by Polymer Publishing Association (1993))”, “Chemistry of Synthetic Latex (Souichi Muroi, Polymer Publishing Association) Issuance (1970))).

Examples of such latex polymers include acrylic resins, vinyl acetate resins, polyester resins, polyurethane resins, rubber resins, vinyl chloride resins,
Examples include vinylidene chloride resin and polyolefin resin. The molecular weight of the polymer is 5000 to 100000 in number average molecular weight
0, preferably about 10,000 to 100,000. If the molecular weight is too small, the mechanical strength of the photosensitive layer is insufficient,
If the size is too large, the film-forming property is poor, which is not preferable.

Specific examples of such a polymer include methyl methacrylate / ethyl acrylate / methacrylic acid copolymer, methyl methacrylate / 2-ethylhexyl acrylate / styrene / acrylic acid copolymer,
Styrene / butadiene / acrylic acid copolymer, styrene / butadiene / divinylbenzene / methacrylic acid copolymer and the like are exemplified. As the polymer, various commercially available products are also available. For example, as an acrylic resin, Sebian A-4635 manufactured by Daicel Chemical Industries, Ltd., and as a polyester resin, FINETEX ES manufactured by Dainippon Ink and Chemicals, Inc.
650, polyurethane resin such as HYDRAN AP10 manufactured by Dainippon Ink and Chemicals, rubber-based resin such as LACSTAR 7310K manufactured by Dainippon Ink and Chemicals, and vinyl chloride resin such as G351 manufactured by Zeon Corporation. Examples of the vinylidene chloride resin include L502 manufactured by Asahi Kasei Corporation, and examples of the polyolefin resin include Chemipearl S124 manufactured by Mitsui Petrochemical Co., Ltd. These polymers may be used alone or as a blend of two or more.

The average particle size of the dispersed particles in the latex is 1 nm
The range is preferably about 5 to 1000 nm, more preferably about 5 to 1000 nm. There is no particular limitation on the particle size distribution of the dispersed particles, and a material having a wide particle size distribution or a material having a monodispersed particle size distribution may be used. Minimum film formation temperature of latex (MF
T) is −30 ° C. to 90 ° C., more preferably 0 ° C. to 70 ° C.
Is preferred.

As described above, in the image forming layer of the first recording material, it is preferable that 50% by weight or more of the total binder is latex, and that 70% by weight or more is latex. If necessary, a hydrophilic polymer such as gelatin, polyvinyl alcohol, methylcellulose, hydroxypropylcellulose, carboxymethylcellulose, or hydroxypropylmethylcellulose may be added to the image forming layer in a range of 50% by weight or less of the total binder. good. Further, the dispersed particles (polymer) of the latex are 2
It is preferable that the average water content at 5 ° C. and 60% RH be 2 wt% or less, more preferably 1 wt% or less.

Such a first recording material may have various layers in addition to the above-described image forming layer. For example, a surface protective layer, an antihalation layer, a back (coat) layer formed on the surface opposite to the image forming layer of the support, and a layer formed on the same surface as the back layer for the purpose of protecting the image forming layer and preventing adhesion. Backside resistive heating lay
er), an antistatic or conductive layer, a vapor-deposited metal layer, and the like.

The image-forming layer of the first recording material or another layer on the same side as the image-forming layer may contain, in addition to these essential components, a color tone agent, a sensitizing dye, an antifoggant, Agents, stabilizer precursors, benzoic acids for the purpose of increasing sensitivity and preventing fogging, mercapto compounds and sisulfide compounds for the purpose of suppressing or accelerating development, improving spectral sensitization efficiency, and improving storage stability before and after development Known additives contained in recording materials, such as thione compounds, dyes and pigments for the purpose of improving color tone, preventing irradiation, plasticizers, lubricants, ultra-high contrast agents, high-contrast accelerators, hardeners, etc. May be contained.

As another example of a suitable light and heat sensitive recording material used in the present invention, the following recording materials are exemplified. This light and heat sensitive recording material (hereinafter referred to as a second recording material)
A recording material comprising a heat-sensitive (thermochromic) image-forming layer provided on a support, wherein the image-forming layer comprises an electron-donating colorless dye encapsulated in a heat-responsive microcapsule and a heat-responsive microcapsule. In addition, a recording material containing a compound having an electron acceptor and a polymerizable vinyl monomer in the same molecule and a photopolymerization initiator. Further, as another photosensitive / thermosensitive recording material (hereinafter, referred to as a third recording material), a recording material in which a photosensitive / thermosensitive (thermochromic) image forming layer is provided on a support, wherein the image forming layer is It is a recording material containing an electron-donating colorless dye encapsulated in heat-responsive microcapsules, and an electron-accepting compound, a polymerizable vinyl monomer, and a photopolymerization initiator in addition to the heat-responsive microcapsules.

The second and third recording materials cure the composition (hereinafter referred to as a photocurable composition) outside the thermoresponsive microcapsules by exposure to light, and are fixed. As a result, the compound having mobility (not immobilized) having the electron accepting portion and the polymerizable vinyl monomer portion or the electron accepting compound moves in the image forming layer, and the electron donating property in the microcapsule is changed. Is a recording material that forms an image by developing a colorless dye of the formula (1). Both recording materials are disclosed in Japanese Patent Application No. 8-3337 by the present applicant.
No. 24 describes this in detail.

The compound having an electron-accepting portion and a polymerizable vinyl monomer portion in the same molecule, which is used in the photocurable composition of the second recording material, refers to an electron-accepting group and a vinyl group in one molecule. Is a compound containing Specifically, styrenesulfonylaminosalicylic acid, vinylbenzyloxyphthalic acid, zinc β- (meth) acryloxyethoxysalicylate, vinyloxyethyloxybenzoic acid, β- (meth) ataacryloxyethylorselinate, β- ( (Meth) acryloxyethoxyphenol, β- (meth) acryloxyethyl-β-resorcinate, hydroxystyrenesulfonic acid-N-ethylamide, β- (meth) acryloxypropyl-p-hydroxybenzoate,
(Meth) acryloxymethylphenol, (meth) acrylamidopropanesulfonic acid, γ-styrenesulfonyloxy-β- (meth) acryloxypropanecarboxylic acid, and the like, and a metal salt thereof, for example, a zinc salt can be preferably used.

The above compound can be suitably used also as a polymerizable vinyl monomer of the photocurable composition of the third recording material. In addition, as the polymerizable vinyl monomer used in the third recording material, a monomer having at least one vinyl group in a molecule, particularly a monomer having a plurality of vinyl groups in a molecule is preferable. For example, ethylene glycol diacrylate, ethylene glycol dimethacrylate, trimethylolpropane triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hydroxypentaacrylate,
Hexanediol-1,5-dimethacrylate, diethylene glycol dimethacrylate and the like are exemplified. As these monomers, those having a molecular weight of about 100 to about 5000 are preferably used.

The photopolymerization initiator used in the second and third recording materials is a compound capable of initiating the photopolymerization of the vinyl monomer, and is preferably used in combination with a green, red to infrared absorbing dye. In addition, it is said that it has sensitivity in this wavelength region and generates radicals upon irradiation with light (Japanese Patent Application Laid-Open No.
No. 143044) Organic borate salt compounds, more preferably organic borate salts of cationic dyes. The organic borate generates a radical in response to the irradiated laser beam, and the radical initiates the polymerization of the vinyl monomer portion.

As the organic borate salt, a compound represented by the following general formula (1) is used.

Embedded image

In the above general formula (1), M is
Li metal atom, quaternary ammonium, pyridinium, quino
Linium, diazonium, morpholinium, tetrazoli
, Acridinium, phosphonium, sulfonium,
Oxosulfonium, sulfur, oxygen, carbon, halogeniu
, Cu, Ag, Hg, Pd, Fe, Co, Sn, M
cation selected from o, Cr, Ni, As, Se
N is an integer of 1 to 6, R ¹, R^Two, R^ThreeAnd R^Four
Each represents a halogen atom, a substituted or unsubstituted alkyl
Group, substituted or unsubstituted alkenyl group, substituted or unsubstituted
Substituted alkynyl group, alicyclic group, substituted or unsubstituted ant
Alkenyl group, substituted or unsubstituted alkaryl group,
Is an unsubstituted aryloxyl group, a substituted or unsubstituted
Alkyl group, substituted or unsubstituted heterocyclic group, substituted or unsubstituted
Represents a substituted silyl group. Where R¹, R^Two, R^ThreeAnd
And R^FourMay be the same or different from each other, and these
Of these, two or more groups may be bonded to form a cyclic structure.

In the above formula (1), examples of the borate anion include tetraethyl borate, triisobutyl methyl borate, di-n-butyl-di-t-butyl borate, tetraphenyl borate, tetra-p-chlorophenyl borate, and tri-borate. m-chlorophenyl-n-hexyl borate, triphenylethyl borate, trimethylbutyl borate, tolyl isopropyl borate,
Triphenylbenzyl borate, tetraphenyl borate, tetrabenzyl borate, triphenylphenethyl borate, triphenyl-p-chlorobenzyl borate, triphenylethenituburiborate, di (α-nephthyl) -dipropyl borate, triphenylsilyl triphenyl Examples thereof include borate, tritolylsilylphenyl borate, and tri-n-butyl (dimethylphenylsilyl) borate.

The following is an example of the organic borate salt represented by the general formula (1).

Embedded image

In order to increase the light absorption efficiency of the recording light L or the like,
The organic borate salt represented by the general formula (1) is preferably used as a spectral sensitizing dye in combination with green to red and infrared absorbing dyes. Particularly, the maximum absorption wavelength is 500 to 1
Organic cationic dyes having a wavelength range of 100 nm are preferably used, and specifically, cationic methine dyes,
Examples include a cationic carbonium dye, a cationic quinone imine dye, a cationic indoline dye, and a cationic styryl dye. More specifically, as the cationic methine dye, polymethine dye, cyanine dye, azomethine dye, more preferably cyanine, carbocyanine, dicarbocyanine, tricarbocyanine, hemicyanine, etc., as a cationic carbonium dye , A triarylmethane dye, a xanthene dye, an aridudine dye, more preferably a rhodamine, etc. These can be used alone or in combination of two or more.

As the photopolymerization initiator, more preferably,
An organic borate salt of a cationic dye represented by the following general formula (2) is used.

[0045]

Embedded image

In the above formula (2), D ⁺ represents a cationic dye, and R ¹ , R ² , R ³ and R ⁴ are a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl. Group, substituted or unsubstituted aralkyl group, substituted or unsubstituted alkaryl group, substituted or unsubstituted alkenyl group, substituted or unsubstituted alkynyl group, substituted or unsubstituted aryloxyl group, substituted or unsubstituted allylic group It is a group selected from a click group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted allyl group, a substituted or unsubstituted silyl group, and an alicyclic group. Also,
R ¹ , R ² , R ³ and R ⁴ may be the same or different from each other, and two or more of these groups may be bonded to form a cyclic structure.

In the above general formula (2), the cationic dye represented by D ⁺ acts as a spectral sensitizing dye, and has a wavelength region of 500 nm or more, especially 550 nm to 550 nm.
An organic cationic dye having an absorption peak in a wavelength region of 1100 nm is preferably exemplified. Specifically, as such an organic cationic dye, those exemplified for the compound of the general formula (1) can be suitably used. Further, as the borate anion, the same ones as in the general formula (1) are preferably exemplified.

An example of the organic borate salt of the cationic dye represented by the general formula (2) is shown below.

Embedded image

[0049]

Embedded image

The content of these photopolymerization initiators is preferably 0.01% by weight to 20% by weight based on the total weight of the photocurable composition (outside of the thermoresponsive microcapsules).

In both recording materials, 2-phenyl-4,6-bis (trichloromethyl) -S-triazine and 2- (p-chlorophenyl) -4 were used together with the above-mentioned photopolymerization initiator and spectral sensitizing dye. , 6-Bis (trichloromethyl)-
S-triazine, 2- (p-methoxyphenyl) -4,
6-bis (trichloromethyl) -S-triazine, carbon tetrachloride, carbon tetrabromide, iodoform, p-nitro-α,
A compound having an active halogen group in the molecule, such as α, α-tribromoacetophenone, can be used in combination as an auxiliary. These compounds are preferably added in an amount of 0.01 to 20 mol based on 1 mol of the spectral sensitizing dye (cationic dye).

An electron-accepting compound is added to the photocurable composition of the third recording material. Further, an electron-accepting compound may be added to the photocurable composition of the second recording material, if necessary, so that the coloring density can be improved.
Examples of the electron accepting compound include phenol derivatives such as 2,2'-bis (4-hydroxyphenyl) propane, 4-t-butylphenol, and 4-phenylphenol;
Salicylic acid derivatives such as pentadecylsalicylic acid, 3,5-di (α-methylbenzyl) salicylic acid, 3,5-di (tert-octyl) salicylic acid, metal salts of aromatic carboxylic acids, acid clay, bentonite, novolak resins, Metal-treated novolak resins, metal complexes, and the like. These electron accepting compounds are preferably used in an amount of about 5% by weight to about 1000% by weight of the colorless electron donating dye.

The photocurable composition of such a recording material has, in addition to these compounds, a photocrosslinkable composition such as polyvinyl cinnamate, polyvinyl cinnamylidene acetate, and α-phenylmaleimide group. You may add a photocurable composition etc. Further, these photocrosslinkable compositions may be used as photocurable components. Furthermore, in the photocurable composition, in addition to these compounds, if necessary, to prevent thermal and temporal polymerization of the photocurable composition, with the aim of enhancing stability , P-methoxyphenol, hydroquinone, pyrogallol, 2-hydroxybenzophenone, cuprous chloride and the like may be added. These are present in an amount of 0.1% based on the total weight of the photocurable composition.
It is preferable to add about 001% by weight to 5% by weight.

The photocurable composition is emulsified and dispersed and contained in the image forming layer. Solvents used for emulsifying and dispersing the photocurable composition include cottonseed oil, kerosene, aliphatic ketone, aliphatic ester, paraffin, naphthenic oil, alkylated biphenyl, chlorinated paraffin, phosphate esters such as diphenyl phosphate, and acetyl. Citrate esters such as tributyl citrate; benzoic esters such as octyl benzoate; (meth) such as methyl (meth) acrylate
Examples thereof include acrylates, alkyl halides such as methylene chloride and carbon tetrachloride, and methyl isobutyl ketone. Aliphatic esters and alkyl halides are preferred, and those having a solubility in water of 10% by volume or less are more preferred. These solvents are used for the photopolymerizable compound.
It is preferably used in a proportion of from 500 parts by weight to 500 parts by weight.

As the water-soluble polymer that can be used for emulsifying and dispersing the photocurable composition, a compound that is soluble in water at 25 ° C. in an amount of 5% by weight or more is preferable. Derivatives, proteins such as albumin, cellulose derivatives such as methylcellulose, sugar derivatives such as starches (including modified starch), polyvinyl alcohol, carboxy-modified polyvinyl alcohol, polyacrylamide, saponified vinyl acetate-polyacrylic acid copolymer, Synthetic polymers of polystyrene sulfonate sugars are mentioned, and gelatin and polyvinyl alcohol are particularly preferable.

On the other hand, as the electron-donating colorless dye encapsulated in the microcapsules of the image forming layers of both recording materials, various conventionally known dyes can be used. In particular,
Triphenylmethanephthalide-based compounds such as 3,3-bis (p-dimethylaminophenyl) -6-dimethylaminophthalide, leuco-auramine-based compounds such as N-halophenyl-leuco-auramine, rhodamine-B-anilino Lactams and other rhodamine lactam compounds; 2- (dibenzylamino) fluoran and other fluoran compounds; phenothiazine compounds such as benzoyl leuconmethylene blue; spiropyran compounds such as 3-methyl-spiro-dinaphthopyran; Various compounds can be used, such as a sulfide compound, a totaphenylmethane compound, a triazene compound, and a fluorene compound. When this recording material is a full-color recording material, U.S. Pat. No. 4,900,149 is used as an electron-donating colorless dye for cyan, magenta, and yellow, and U.S. Pat. , 80
0,148, etc., and JP-A-63-53542, etc., for the cyan coloring type.

Microcapsules containing such an electron-donating colorless dye can be obtained by a method known in the art. For example, an interfacial polymerization method disclosed in Japanese Patent Publication No. 42-771, a method by precipitation of a polymer disclosed in U.S. Pat. No. 3,660,304, and a method disclosed in U.S. Pat. No. 3,796,669. Method using the disclosed isocyanate polyol wall material, U.S. Pat.
A method using an isocyanate wall material disclosed in 914,511, a method using a urea formaldehyde-resorcinol-based wall forming material disclosed in U.S. Pat. No. 4,089,802, and the like are disclosed. Especially,
It is preferable to form a polymer film as a microcapsule wall after emulsifying the core substance.

In particular, a microencapsulation method by polymerization of a reactant from the inside of an oil droplet is preferable in that a recording material having a capsule having a uniform particle size and excellent preservability can be obtained within a short time. For example, when polyurethane is used as a capsule wall material, a polyvalent isocyanate such as m-phenylene diisocyanate or 2,6-tolylene diisocyanate and a second substance which reacts therewith to form urethane (capsule wall) (for example, Polyols such as aliphatic or aromatic polyhydric alcohols and polyamines such as ethylenediamine and trimethylenediamine) are mixed in an oily liquid to be encapsulated, emulsified and dispersed in water, and then the temperature is increased. A polymer formation reaction occurs to form microcapsule walls. At this time, an auxiliary solvent having a low boiling point and strong dissolving power can be used in the oily liquid.

The microcapsules can also be prepared using a water-soluble polymer such as a water-soluble anionic polymer, a nonionic polymer and an amphoteric polymer. Arabic gum, alginic acid, sulfated starch,
Sulfated cellulose, (meth) acrylic acid-based (co) polymer, carboxy-modified polyvinyl alcohol, etc., nonionic polymers include polyvinyl alcohol, hydroxyethylcellulose, etc., and amphoteric compounds include gelatin, etc. , Gelatin, gelatin derivatives and polyvinyl alcohol are preferred. The water-soluble polymer is 0.0
It is used as a 1% to 10% by weight aqueous solution.

In such a recording material, the average particle diameter of the capsule is 20 μm or less, and particularly preferably 5 μm or less from the viewpoint of resolution. On the other hand, if the capsule is too small, the surface area for a certain solid content becomes large, and a large amount of a wall material is required. Therefore, the average particle size is preferably 0.1 μm or more. The colorless electron-donating dye may be present in a solution state in the microcapsule, or may be present in a solid state.

The second and third recording materials may have various layers such as a protective layer and an intermediate layer in addition to the image forming layer. Further, in each layer of the image forming layer, the intermediate layer and the protective layer of the recording material, particularly in the protective layer, a curing agent,
It is preferred to use a "gelatin hardener" such as chrom alum or zirconium sulfate used in the production of photographic light-sensitive materials. Each layer of the recording material is further coated with various surfactants such as ionic surfactants such as saponin and polyethylene oxide for various purposes such as coating aids, antistatic, improving slipperiness, emulsifying and dispersing, and preventing adhesion. May be used, besides this, dyes for preventing irradiation and halation, ultraviolet absorbers, plasticizers, fluorescent brighteners,
Various additives such as a coating aid, an antistatic agent and a slipperiness improver may be added. Also, it is preferable to add a known matting agent such as silica or polystyrene in the protective layer, and may further include colloidal silica such as Nissan Chemical's Snowtex series to reduce the adhesiveness, A fluorescent whitening agent for increasing the whiteness of the recording material or a blue dye as a bluing agent may be added.

The first, second and third recording materials having such characteristic image forming layers are prepared by preparing a coating solution (emulsion) containing the components of each layer by using a solvent, if necessary. It can be produced by applying and drying by a known means. Further, the support of these recording materials is not particularly limited, and various materials used in ordinary recording materials can be used. Specifically, polyester films, polyethylene terephthalate (PET) films,
Examples thereof include resin films such as polyethylene naphthalate film, cellulose nitrate film, cellulose ester film, polyvinyl acetal film, and polycarbonate film, various metals such as aluminum, zinc, and copper, glass, and paper.

The recording apparatus 10 of the illustrated example, which performs image recording using such a photosensitive and heat-sensitive recording material A (hereinafter, referred to as a recording material A), basically supplies the photosensitive material in the transport direction of the recording material A. Unit 12, width adjustment unit 14, image exposure unit 16
, A heat developing unit 18 and a discharge tray 80. Further, a light source 82 and a sensor 84 for measuring the density of the recording material A that has been subjected to the heat development are arranged between the heat developing unit 18 and the discharge tray 80. Although not shown in FIG. 1 in order to simplify the drawing and clarify the configuration, the recording apparatus 10 includes a conveying roller and a guide for conveying the recording material A, in addition to the illustrated members. , Various sensors and the like are arranged as needed.

The recording material A is usually formed into a laminate (bundle) of a predetermined unit such as 100 sheets and wrapped in a bag or a band. Are supplied to the recording device 10 and supplied to the recording device 10 one by one. Note that the recording material A is a transparent material as described above. The photosensitive material supply unit 12 (hereinafter, referred to as a supply unit 12) takes out one recording material A from the magazine 20 and downstream of the recording material A in the transport direction (hereinafter, referred to as a supply direction).
At the part to be supplied to the width approaching part 14 positioned at the downstream), the sheet feeding means using the suction cups 26 and 28 disposed at each of the loading parts, and the supply roller pairs 30 and 32; Transport roller pairs 34 and 36;
It has transport guides 38, 40 and 42.

The loading sections 22 and 24 are sections for loading the magazine 20 containing the recording material A at a predetermined position.
The illustrated recording apparatus 10 includes two loading units 22 and 24.
Usually, recording materials A having different sizes (for example, half-cut size for CT and MRI, B4 size for FCR (Fuji Computed Radiography), etc.) are stored in both loading sections. The magazine 20 is loaded.
The single-wafer means arranged in each loading section includes suckers 26 and 28
The recording material A is sucked and held, and the recording material A is conveyed by moving the suction cups 26 and 28 by a known moving means such as a link mechanism, and is supplied to the supply roller pairs 30 and 32 disposed in the respective loading sections. Supply. The recording material A supplied to the supply roller pair 30 is supplied to the conveyance guides 38 and 4.
The recording material A supplied to the supply roller pair 32 while being guided by the transport rollers 40 while the guide material 40 is guided by the transport guides 40 and 42. 14.

The width shifter 14 adjusts the position of the recording material A in a direction perpendicular to the conveying direction (hereinafter referred to as the width direction) so that the position of the recording material A in the main scanning direction in the downstream recording unit 16 is adjusted. This is a part where the recording material A is conveyed to the downstream image exposure unit 16 by the conveyance roller pair 44 after taking the so-called side resist. There is no particular limitation on the method of the side resist in the width shifter 14. For example, a resist plate that contacts one end surface in the width direction of the recording material A to perform positioning, and the recording material A is pushed in the width direction to move the end surface. Using a pressing means for bringing the recording material A into contact with the resist plate, and controlling the conveying direction of the resist material and the recording material A in the width direction and making the recording material A contact the resist plate in the same manner. Various known methods, such as a method using a guide plate or the like that can be moved according to the conditions, are exemplified.

The image exposing section 16 (hereinafter, referred to as the exposing section 16) is a portion for imagewise exposing the recording material A by light beam scanning exposure.
8 is provided.

FIG. 2 is a conceptual diagram of the exposure unit 16. The exposure unit 46 uses a solid-state laser excited by a semiconductor laser as a light source of the light beam L, modulates the light beam L with an external modulator in accordance with a recorded image, and also modulates the light beam L in a main scanning direction (perpendicular to the plane of FIG. Direction, and is incident on a predetermined recording position X. In the light beam scanning device, a light source 50, an optical modulator 52, a polygon mirror 54 as an optical deflector,
lens 56, falling mirror 58, driver 92 of light source 50, drive current setting means 90 (hereinafter referred to as setting means 90), exposure control means 88, and pattern memory 86. You. The exposure unit 46
In addition to the above, various types of collimator lenses and beam expanders for shaping the light beam L emitted from the light source, surface tilt correction optical system, mirrors for changing the optical path, etc. The members are arranged as needed.

The light source 50 emits a light beam L for recording a latent image on the recording material A. In the present invention, a solid-state laser excited by a semiconductor laser is used as the light source 50. There are no particular limitations on the solid-state laser that can be used in the present invention. Any known solid-state laser can be used as long as it can be excited by a semiconductor laser and emit a light beam L in a narrow band wavelength range according to the spectral sensitivity characteristics of the recording material A. The solid-state laser described above can be used, but examples thereof include a YAG laser and a YLF laser. Also, a semiconductor laser that can realize a desired wavelength and output may be appropriately selected according to a solid-state laser to be used. In the illustrated device, the light source 50
Is the driving current (supply current to the semiconductor laser) set by the setting means 90 by the driver 92 whose driving current is variable.
Driven by The setting unit 90 determines the density from the transmitted light amount of the step wedge pattern measured by the sensor 84 and sets the drive current of the light source 50. This will be described in detail later.

The light beam L emitted from the light source 50 is modulated by the light modulator 52 driven by the exposure control means 88 according to the recorded image. Image data from an image data source R such as MRI or CT is
Sent to The exposure control unit 88 performs a gradation correction (density correction) on the supplied image data using a gradation correction table.
The optical modulator 52 is driven according to the obtained image data, that is, the recorded image, to modulate the light beam L according to the recorded image. The exposure control means 88 includes a step wedge pattern (a pattern in which a plurality of gray patches of various densities are continuously formed) used for setting the drive current of the light source 50 and creating (calibrating) a gradation correction table. ) Is connected to a pattern memory 86 for storing image data. The image data of the step wedge pattern includes image data corresponding to highlight (lowest density) and shadow (highest density).

In the present invention, there is no particular limitation on the external modulator that can be used, and AOM (acousto-optic modulator), EOM
Known electro-optical modulators such as (electro-optic modulator) and MOM (magneto-optic modulator) can be used. As will be described in detail later, according to the present invention, even if the dynamic range of the optical modulator is narrow, it is possible to satisfactorily reproduce the target density from the minimum density (highlight) to the maximum density (shadow).
As described above, a modulator having excellent responsiveness but basically having a narrow dynamic range can be suitably used. In applications where responsiveness is required, use of an EOM or the like is used to minimize the limitation due to the dynamic range. It is possible to use an optical modulator having characteristics according to the application. In the present invention, modulation is basically performed by intensity modulation.

The light beam L modulated in accordance with the recorded image by the light modulator 52 is deflected in the main scanning direction by the polygon mirror 54, is dimmed by the fθ lens 56 so as to form an image at the recording position X, and stands up. The optical path is changed by the lowering mirror 58 and the light enters the recording position X. The recording device 10 in the illustrated example is a device that performs monochrome image recording, and the exposure unit 46 has only one light source 50.
When the present invention is used for recording a color image, for example,
R (red), G (green), and B (blue) of color photosensitive materials
An exposure unit having three types of light sources that emit light beams having wavelengths corresponding to the spectral sensitivity characteristics of the light source is used.

On the other hand, the sub-scanning conveyance means 48
A pair of transport rollers 60 arranged with the (scanning line) interposed therebetween
The recording material A is conveyed in the sub-scanning direction (the direction of arrow a in FIG. 2) orthogonal to the main scanning direction while holding the recording material A at the recording position X by the conveying roller pairs 60 and 62. Here, as described above, since the light beam L modulated according to the recorded image is deflected in the main scanning direction, the recording material A is two-dimensionally scanned and exposed by the light beam, and the latent image is recorded. Is done.

The recording material A on which the latent image has been recorded in the exposure section 16 is then transported by the transport roller pairs 64 and 66 and the like, and is transported to the thermal developing section 18. The heat developing section 18 is a part that performs a heat development by heating the recording material A to convert a latent image into a visible image, and includes a heating drum 68, an endless belt 70, and a peeling claw 72. Is done.

The heating drum 68 is a drum having a built-in heating light source such as a halogen lamp and a heat source such as a heater. The surface of the heating drum 68 is heated and held at a temperature corresponding to the heat development temperature of the recording material A. The recording material A is pinched and conveyed together with the endless belt 70 by rotating about the shaft 68a. In addition,
The temperature of the heating drum 68 is, for example, 100 ° C. to 1 ° C. when the first recording material is used as the recording material A.
40 ° C., and 85 ° C. to 150 ° C. when the second and third recording materials are used. Further, the heat development time may be adjusted by changing the conveyance speed according to the type of the recording material A. For example, the heat development time is 10 seconds to 90 seconds for the former recording material, and the heat development time for the latter recording material. If there is, it is about 3 to 60 seconds.

The endless belt 70 has rollers 74a,
It is stretched around four rollers 74b, 74c and 74d and is pressed so as to be wound around the heating drum 68. The peeling claw 72 applies the recording material A to the heating drum 68.
The recording material A is conveyed by the heating drum 68, and the recording material A is lightly contacted with and separated from the heating drum 68.

The recording material A conveyed to the thermal developing section 18 by the conveying roller pair 66 is nipped and conveyed by an endless belt 70 and rollers 76 and 78, and conveyed between the heating drum 68 and the endless belt 70. While being conveyed in accordance with the rotation of the heating drum 68, the latent image which is thermally developed by the heating drum 68 and recorded by exposure becomes a visible image. When the leading end of the recording material A is conveyed to the vicinity of the peeling claw 72, the peeling claw 72 lightly comes into contact with the heating drum 68 and penetrates between the heating drum 68 and the recording material A. Peel from 68.

The recording material A peeled from the heating drum 68 by the peeling claw 72 after the completion of the thermal development is conveyed outside the apparatus and discharged to the discharge tray 80. Here, a light source 82 and a sensor 84 are arranged between the thermal developing unit 18 and the discharge tray 80 so as to sandwich the conveyance path of the recording material A. As described above, since the recording material A is a light-transmitting film material using a transparent support, the light emitted from the light source 82 and transmitted through the recording material A is measured by the sensor 84 so that the recording material A is measured. Can be measured. In the recording apparatus 10 of the illustrated example, a step wedge pattern is recorded at the time of setting a driving current of the light source 50 or at the time of creating a gradation correction table, and the transmitted light amount is determined by the light source 8.
2 and the sensor 84. The measurement result by the sensor 84 is sent to the setting means 84 and the exposure control means, from which the density of the step wedge pattern is calculated.

In the present invention, the method for measuring the concentration is not limited to the above method, and various known concentration measuring means can be used. For example, the concentration may be measured using various concentration meters. When the recording material is non-transparent, the density may be measured by measuring the reflected light. Further, the recording apparatus 10 of the illustrated example has a built-in density measuring unit, but the present invention is not limited to this, and the density of a step wedge pattern or the like may be measured using an external measuring unit.

Hereinafter, the present invention will be described in more detail by describing the operation of the recording apparatus 10 when determining the drive current of the light source 50.

As described above, the recording material A is supplied from the supply section 12
And the side resist is removed at the width shifter 14, and is conveyed to the exposure unit 16. The recording material A conveyed to the exposure unit 16 is conveyed in the sub-scanning direction by the sub-scanning conveyance unit 48, and is emitted from the exposure unit 46, modulated according to the recording image, and deflected in the main scanning direction.
The scanning exposure is performed two-dimensionally to record a latent image.

Here, when setting the driving current of the light source 50, the driving current of the light source 50 is changed to a plurality of types, and a step wedge pattern is formed by each driving current.
That is, when an instruction to (re) set the drive current of the light source 50 is issued, the setting unit 90 selects one of a plurality of predetermined drive currents, for example, the current value I _1. The exposure control means 88 reads the image data of the step wedge pattern from the pattern memory 86 and drives the light modulator 52 accordingly. As a result, a latent image having a step wedge pattern is formed on the recording material A.

Next, the setting means 90 sets another current value I ₂
Is selected, the light source 50 is driven, and the latent image of the step wedge pattern is formed in the same manner by the driving of the light modulator 52 by the exposure control means 88. Similarly, different current values I ₃ and I ₄ To form a step wedge pattern. In this example, as an example, the current value is set to I ₁ <I ₂ <I ₃ <I ₄ .

The number of current values for forming the step wedge pattern at the time of setting the drive current of the light source 50 is not limited to four, but may be appropriately determined in accordance with possible variations in the characteristics of the recording material A. , The greater the number of current values, the greater the light modulator 5
Although efficient image recording can be realized by effectively utilizing the dynamic range of 2, the setting of the drive current takes a long time. Therefore, the number of types is usually two to five. If possible, a plurality of step wedge patterns may be recorded on one recording material A.

The recording material A on which the latent image has been recorded in the exposing section 16 is conveyed to the heat developing section 18 by conveying roller pairs 64, 66 and the like, where the heating drum 68 and the endless belt 7
The latent image (step wedge pattern) is conveyed while being sandwiched between the two and thermally developed, and the latent image (step wedge pattern) is made a visible image.
Is separated from the heating drum 68 by the discharge tray 8
Transported to zero. Here, when setting the drive current of the light source 50, as described above, the amount of light emitted from the light source 82 and transmitted through the recording material A is measured by the sensor 84, sent to the setting unit 90, and sent to the setting unit 90. Then, the image density of the step wedge pattern is calculated from the transmitted light amount, and the driving current of the minimum output that has developed the predetermined maximum density _Dmax is set as the driving current of the light source 50.

FIG. 3 shows the coloring of the recording material (negative recording material).
Characteristics (logarithm of exposure amount "logE" and color density "D"
An example is shown below. For example, the driving current I_FourRecorded in
When the density range of the step wedge pattern is D_FourAnd similar
Drive current I_ThreeConcentration range at D_Three, Drive current I_TwoAt
Density range is D _Two, Drive current I₁Concentration range at D₁In
The maximum density D required for this image recording_maxTo
The realized driving current is I_Four, I_ThreeAnd I_TwoIn three kinds
Therefore, the setting means 90 determines that the driving current I_Two
Is selected as the drive current of the light source 50 and the driver 92
Set.

As a result, the effective dyna
E Mick Range_TwoAs the highest concentration D_maxRealizing
Other drive current I_FourAnd I_ThreeDynamic
Nji E_FourAnd E_ThreeOver a wider concentration range
Image recording. Or, at a later date,
When this was performed, the characteristics of the recording material A fluctuated with time, and FIG.
Is shifted rightward, and the drive current I
_TwoThen the highest concentration D _maxIf it becomes impossible to realize
I_FourOr I_Three, The highest concentration D_maxThan realized
A small drive current is selected. That is, according to the present invention,
For example, a semiconductor laser pumped solid-state laser
Image recording with light beam scanning exposure using a partial modulator
And the driving current of the light source 50 is changed according to the characteristics of the recording material A.
By setting, the dynamic range of the optical modulator 52 is set.
Effectively use the maximum density D_maxAfter realizing,
Efficient image recording over a wide density range
Image recording can be performed.

On the other hand, the density of the step wedge pattern calculated by the setting means 90 is also sent to the exposure control means 88. The exposure control unit 88, when a drive current is set from the setting device 90, using the density measurement result of the step wedge pattern at the driving current I ₂ that is set to create the gradation correction table. There is no particular limitation on the method of creating the gradation correction table, and various known methods can be used.
As an example, the following method is exemplified. That is, the relationship between the image data B of the step wedge pattern and the actual image density (color density) D is shown in the first quadrant of FIG. When the image density characteristic g is indicated by the second quadrant in FIG. 4, first, image data A for obtaining an image density D corresponding to each image data B below the image density characteristic g is obtained. Relation f with image data B
(Fourth quadrant in FIG. 4). Note that the relationship f between the image data A and the image data B can be continuously obtained by obtaining a plurality (for example, about 24 points) of image data B on which a step wedge pattern is recorded and then interpolating them. . Finally, based on the relationship f between the image data A and the image data B, a gradation correction table for converting the image data A into the signal B is created.

After setting the drive current of the light source 50 and creating the gradation correction table in this way, the setting means 9
0 sets the driving current I ₂ to the driver 92, The exposure control means 88, the newly created tone correction tape -
Is set to the image processing means, and the subsequent image recording
It drives the light source 50 with the driving current I _2, the gradation correction tape newly created - by correcting the image data from the image data supply source R using Bull, by driving the optical modulator 52, the image recording (Recording of latent image on recording material A) is performed.

In the present invention, the timing for setting the driving current of the light source 50 is not particularly limited.
It may be performed every time a certain period elapses, may be performed according to image quality deterioration, may be performed at the time of the first recording when a magazine 20 containing a new bundle of recording materials A is loaded,
It may be performed at the time of the first recording when the magazine 20 is exchanged, may be performed at the same time as resetting the gradation correction table, or may be performed in combination. Further, when the magazine 20 is replaced or a new bundle of the recording material A is loaded, the correction of the driving current of the light source 50 and the resetting of the gradation correction table may be automatically performed. The loading of a new bundle of recording materials A may be detected by the fact that the magazine 20 is empty.

In the above example, a negative recording material is used as an example. Therefore, the lowest driving current that achieves a predetermined maximum density is set as the driving current for the light source 50. In the case of using the light source 50, the lowest drive current that achieves a predetermined minimum density (highlight) may be set as the drive current of the light source 50.

Although the image recording method and the image recording apparatus of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various improvements and modifications can be made without departing from the gist of the present invention. Of course you can do it.

[0093]

As described in detail above, according to the present invention, a semiconductor laser pumped solid-state laser is used as a light source,
In image recording by light beam scanning exposure in which modulation is performed by an external modulator, even when an external modulator with a narrow dynamic range is used, the dynamic range is effectively used to respond well to the characteristics of the recording material. Thus, image recording in a wide density range can be performed efficiently.

[Brief description of the drawings]

FIG. 1 is a schematic view of an example of an image recording apparatus according to the present invention.

FIG. 2 is a schematic diagram of an image exposure unit of the image recording apparatus shown in FIG.

FIG. 3 is a graph for explaining a method of setting a drive current of a light source in the image recording apparatus shown in FIG.

4 is a graph for explaining a method of creating a gradation correction table in the image recording apparatus shown in FIG.

FIG. 5 is a graph showing an example of a coloring property of a recording material.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 (Image) recording apparatus 12 (Recording material) supply part 14 Width adjustment part 16 (Image) exposure part 18 Thermal development part 20 Magazine 22, 24 Loading part 26, 28 Suction cup 30, 32 Supply roller pair 34, 36, 44, 60, 62, 64, 66 Conveying roller pair 38, 40, 42 Conveying guide 46 Exposure unit 48 Scanning conveying means 50, 82 Light source 52 Light modulator 54 Polygon mirror 56 fθ lens 58 Falling mirror 68 Heating drum 70 Endless belt 72 Peeling Claws 74a, 74b, 74c, 74d, 76, 78 Roller 80 Discharge tray 84 Sensor 86 Pattern memory 88 Exposure control means 90 (drive current) setting means 92 Driver A Recording material

Claims (3)

[Claims] 1. An image recording method for modulating a light beam using a semiconductor laser-excited solid-state laser as a light source by an external modulator, and scanning and exposing a recording material to record an image, comprising: The semiconductor laser pumped solid-state laser is driven, the light beam is modulated by the external modulator, a step wedge pattern is recorded on a recording material, and the image densities of the obtained plurality of step wedge patterns are measured. From the drive current, when the recording material is a negative recording material, the step wedge pattern is the minimum drive current that has achieved a predetermined maximum density, and when the recording material is a positive recording material, the step wedge pattern is A minimum drive current that achieves a predetermined minimum density is selected, and image recording is performed using this drive current as a drive current of the semiconductor laser-excited solid-state laser. Characteristic image recording method. 2. An image recording apparatus for exposing a recording material with a light beam modulated according to image data to record an image, comprising: a semiconductor laser-excited solid-state laser for emitting the light beam; A driving source having a variable driving current for driving a laser, a modulator for modulating a light beam emitted from the semiconductor laser-excited solid-state laser, and an image of a step wedge pattern for driving the modulator in accordance with image data Recording control means having data, density measurement means for measuring the density of a recorded image, image recording for driving a modulator in accordance with the image data of the step wedge pattern by the recording control means, and a plurality of types of image recording by the driving source. Driving the semiconductor laser-excited solid-state laser with a driving current is performed, and the density of the obtained Is measured by the density measuring means, and from the plurality of types of driving currents, when the recording material is a negative recording material, the minimum driving current at which the step wedge pattern has achieved a predetermined maximum density is the recording material Is a positive recording material, a step wedge pattern finds a minimum drive current at which a predetermined minimum density is achieved, and sets this as a semiconductor laser-excited solid-state laser by the drive source. An image recording apparatus, comprising: 3. The recording material comprises an organic silver salt, a recording material having an image forming layer containing a reducing agent of an organic silver salt, and a colorless dye having an electron donating property. Encapsulating a thermoresponsive microcapsule, a compound having an electron acceptor and a polymerizable vinyl monomer in the same molecule, a recording material having an image forming layer containing a photopolymerization initiator, and an electron donating colorless dye The recording material according to claim 2, which is at least one selected from three types of recording materials having a thermoresponsive microcapsule, an electron-accepting compound, a polymerizable vinyl monomer, and an image forming layer containing a photopolymerization initiator. The image recording apparatus as described in the above.