JPH0451043A - Image forming method - Google Patents

Abstract

PURPOSE:To improve discrimination of images by successively exposing a point on a heat developable photosensitive material in plural times and specifying the exposure time in one time and interval between each exposure. CONSTITUTION:The heat developable photosensitive material (P) comprising of a binder, photosensitive silver halide, and a reducing agent and/or its precursor is formed on a support, and one point on said material is exposed in plural times and in each developing time t1 and each interval between exposures t2, and t1 and t2 are controlled as follows; t1<= 10 microsec, and t2 <= t1 X 10<5>. Said material undergoes scanning exposure in the arrow (a) direction (main scanning direction) of beams and then, the scanning direction is changed in the arrow (b) direaction (secondary scanning direction) in the next exposure, and the scanning is executed in the order orf (1) - (4), thus permitting high maximum density to be obtained and and discrimination of of images to be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an image forming method for obtaining images with good discrimination by thermal development, and more particularly to scanning exposure using a laser or the like.

[Prior art] Conventionally, by performing the developing process using a dry process using heat,
Photosensitive materials (heat-developable photosensitive materials) that can easily and quickly produce images are well known, and their heat-developable photosensitive materials and image forming methods are described, for example, in Japanese Patent Publication Nos. 43-4921 and 43-4924, ``Fundamentals of Photographic Engineering.'' ” Silver Salt Photography Edition (Published by Corona Publishing in 1879), pages 553-555, and Research Disclosure Magazine, June 1978 issue, pages 9-15 (RD-1)
7029) etc.

There are two types of heat-developable photosensitive materials: those that produce black-and-white images and those that produce color images.In recent years, attempts have been made to develop heat-developable color photosensitive materials that produce color images using various dye-providing substances. There is.

There are various methods for heat-developable color photosensitive materials. For example, a method in which a color image is obtained by releasing or forming a diffusible dye through a thermal ring image and then transferring the dye (
Although this method (hereinafter referred to as a transfer method) requires an image receiving member for transfer, it is superior in terms of image stability and clarity, and processing simplicity and speed. This transfer method heat-developable color photosensitive material and image forming method are disclosed in, for example, JP-A-59-12431, JP-A-59-159159, JP-A-59-181345, JP-A-59-229556;
No. 60-2950, No. 61-52643, No. 61
-61158, 61-61157, 59-1
No. 80550, No. 61-132952, No. 61-13
No. 2952, U.S. Patent No. 4,595,652, U.S. Patent No. 4.590.1'54 and U.S. Patent No. 4,584.267
It is stated in the memorandum of each issue.

On the other hand, as a means for obtaining a hard copy image from an image information signal, there is a method of writing on a silver halide photosensitive material using various light sources. Among them, a method using narrow band width light gi (e.g., laser, semiconductor laser, light emitting diode) as a light source is becoming widely used from the viewpoint of high-speed writing and high image quality because of its high energy concentration density.

[Problems to be Solved by the Invention] In the image exposure method described above, the brightness of the beam is modulated based on the gradation data of the image information to be recorded, and the modulated beam is scanned onto the photosensitive material. , the image is recorded.

Although an acousto-optic modulator (AOM) or the like is used to modulate the beam, there has been a problem that a sufficient dynamic range cannot be achieved with respect to the exposure intensity.

In general, silver halide photographic materials tend to have a soft tone when exposed to high-intensity light sources such as lasers due to so-called reciprocity failure. Therefore, in order to obtain an image with good discrimination, a wide exposure intensity range is required. This tendency is particularly strong in heat-developable photosensitive materials, and there is a problem in that a sufficient maximum density cannot be obtained in the above-mentioned scanning exposure.

In order to solve the above-mentioned problems, an object of the present invention is to provide an image forming method that is easy to process, has good image discrimination, and is suitable for scanning exposure.

Specifically, it is an object of the present invention to provide an image forming method capable of producing high-quality images even on photosensitive materials whose tone becomes soft due to so-called high-intensity reciprocity failure.

[Means for Solving the Problems] The above object of the present invention is to expose a certain point on a photothermographic material having a binder photosensitive silver halide, a reducing agent and/or a reducing agent precursor on a support multiple times. In an image forming method in which an image is obtained by thermally developing the point, when the exposure time of one point is t11 and the exposure interval is t2, t1≦1.
This is achieved by an image forming method characterized by 0 microseconds and t2≦t+X10''.

The present invention will be explained in more detail below.

The present invention is preferably used in a so-called scanning exposure type image forming method. In scanning exposure, an image is recorded by scanning a high-brightness beam onto a photosensitive material based on an image signal, but at this time, the exposure time for each pixel or point on the photosensitive material is extremely short, less than 10 microseconds. It's not rare. When the light intensity is 11 and the exposure time is tl, the exposure "E" is expressed by the relationship E = I t + However, in general, in silver halide photographic materials, even if E is constant, I, t + If it changes, the image density obtained will not be constant. This is so-called reciprocity failure.

In a region where the exposure time t1 used in the above-mentioned scanning exposure is short, the smaller the tl, the lower the image density obtained in the case of a negative-tone photosensitive material.

Further, at this time, the gradation of the photosensitive material also generally becomes softer as the exposure time t1 becomes shorter. Therefore, in the case of a negative-tone photosensitive material, the maximum exposure amount at which the image density is not substantially different from the unexposed image is Emin, the exposure amount at which the desired maximum density is obtained is Ewax, and the necessary exposure range Δ
When E is defined as ΔE=Etaax/Emtn, ΔE increases as the exposure time t1 becomes shorter.

However, as described above, the acousto-optic modulator (AOM) used for laser beam modulation has a problem in that it cannot provide a sufficient dynamic range in terms of exposure intensity beyond 61 described above.

In order to solve this problem, the present inventor conducted extensive research and found that the points on the photothermographic material were exposed multiple times in succession, and the exposure time for each exposure was 10 microseconds or less, and the exposure interval was t+
It has been found that an improved effect can be obtained when xlo or less.

That is, ■ Exposure intensity I, exposure time t1, one exposure (exposure ff
1E=rt+) ■ Exposure intensity 1/n, exposure time t1. Exposure Exposure [2,0
Using two types of exposure methods (exposure ff1E=It+), changing E according to I, and taking the relationship between image density and exposed layer E, we find that t1≦10 microseconds and t2≦
It has been found that when satisfying 11×105, the rate of change of D with respect to E, that is, the gradation, is larger in ■ than in ■.

Therefore, when the dynamic range with respect to the exposure intensity is constant, under this condition, by using the exposure method (2), a high maximum density can be obtained and image discrimination can be improved.

A method of embodying the exposure method of the present invention by scanning exposure will be explained with reference to the drawings (see FIG. 1). FIG. 1 is a conceptual diagram of a state in which a photosensitive material is scanned and exposed with a laser beam. In the next scan, the beam scanned and exposed in the direction of arrow a (main scanning direction) changes its position in the direction of arrow A (sub-scanning direction) and performs exposure. The shaded area is the exposed area,
■、■.

The beam is scanned in the order of (1) and (2), and exposure is performed.

d is the scanning width, and the sub-scanning bit is 21. In Fig. 1, i>
It is d. The cross-sectional area of the beam is S, and the main scanning speed is V.
When a, the average exposure time within the scanning width is S/d Va.

2 is determined by the interval time tb between scanning (2) and scanning (2) and the sub-scanning speed Vb, z-vbtbr.

When the above exposure is performed over the entire surface of the photosensitive material,
The exposure area ratio to the total area is d/p, and there are no areas that are exposed multiple times.

Next, consider the case shown in Figure 2. At this time, i<d, and a portion of the area exposed in one scan is exposed again in the subsequent scan.

At this time, the portion (portion 0 in FIG. 2) that is exposed in the overlapped manner by scan (2) and scan (2) is exposed twice at an interval of tb (=t2). Further, when the entire surface of the photosensitive material is exposed by this method, the area ratio A of the portion exposed twice is 2 (d -1) /d (l≧d/2). ,
When 9<d/2, A=1, and three or more exposures are performed.

In an image obtained by scanning exposure as shown in Fig. 2, the density of the part (2) exposed multiple times is higher than that of other parts from a microscopic perspective, but the image density is usually d! Since the measurement is performed using a much larger diameter aperture, the macroscopic average concentration is measured.

The area ratio A of the portion exposed multiple times to the image forming area on the photosensitive material is preferably 40% or more,
More preferably, it is 70% or more. Particularly preferred is 100%. In scanning exposure as shown in Figure 2,
This can be expressed by replacing it with the ratio of 2 and d,
It is preferable that l≦0.8d, and! It is more preferable that ≦0.656, particularly preferably l≦0.5d
It is.

The effect of the present invention can be obtained if the number of multiple exposures (multiple exposure number) n is 2 or more, and the effect becomes larger as n increases, but when n>10, the effect of increasing n becomes smaller. , -5 A problem arises in that the exposure time becomes longer.

In the present invention, one exposure time t1 is 10 microseconds or less, preferably 3 microseconds or less,
It is particularly preferable that the time is 1 microsecond or less.

Exposure interval t2 is t2≦t1×105, or t2≦t
, X (5X10 palpitations), and t2≦t+
Particularly preferred is X104.

The image signal to be scanned and exposed is scanned with the same image signal multiple times depending on the number of multiple exposures. Alternatively, a method such as performing signal processing in the form of interpolation is possible.

The beam width d of scanning exposure is preferably 500μ or less, more preferably 250μ or less, 10
It is particularly preferable that it is 0μ or less.

As described above, the image forming method of the present invention is suitable for the scanning exposure method, but is not limited to the scanning exposure method. For example, this can be realized by continuously performing short flash exposures of 10 microseconds or less.

This method can be applied in cases where sufficient image discrimination cannot be obtained due to insufficient light convergence with one flash exposure.

Various exposure light sources include tungsten lamps, halogen lamps, xenon lamps, mercury lamps, cathode ray tube flying spots, light emitting diodes, lasers (e.g. gas lasers, YAG lasers, dye lasers, semiconductor lasers, etc.), CRT light sources, and FOT. These can be used alone or in combination. A semiconductor laser and a second harmonic generating element (SHG element) can also be used. In addition, exposure may be performed using light emitted from a phosphor excited by electron beams, X-rays, γ-rays, α-rays, or the like. If necessary, the spectral composition of the light used for exposure can be adjusted using a color filter.

When using a laser as the exposure light source, it is preferable to use at least one semiconductor laser from the viewpoint of miniaturizing the apparatus.

In the image forming method of the present invention, it is preferable that thermal development treatment is carried out immediately after imagewise exposure. The interval from the end of exposure to the start of thermal development is preferably within 10 minutes, more preferably within 3 minutes, particularly preferably within 1 minute.

Although the multiple exposure described in the present invention is effective in silver halide photosensitive materials that undergo conventional wet processing,
Particularly remarkable effects can be obtained in heat-developable photosensitive materials. In the heat development process, the photosensitive material on which a latent image has been formed by exposure is exposed to high temperatures, and also because reducing agents and their oxidants are present in close proximity during the storage period from the latent image formation to the heat development. , the latent image is likely to be left in an unstable state. Therefore, it is considered that a so-called weak latent image (or small latent image) formed by high-intensity, short-time exposure is likely to be easily decomposed.

An advantage of the present invention lies in the discovery of an effective exposure method for improving image discrimination for such heat-developable photosensitive materials.

Hereinafter, the photothermographic material according to the present invention will be explained in detail.

The heat-developable photosensitive material of the present invention can be embodied as a black-and-white photosensitive material or as a color photosensitive material. When producing a color photosensitive material, a dye-providing substance is used.

Examples of dye-providing substances that can be used when the present invention is applied to color light-sensitive materials include, for example, JP-A No. 62-44
No. 737, No. 62-129852, No. 62-1691
For example, the leuco dyes described in U.S. Pat. No. 475,441, or the heat-developable dye bleaching methods described in U.S. Pat. No. 4,235,957, Although the azo dye used can be used as the dye-donating substance, it is more preferable to use a diffusible dye-donating substance that forms or releases a diffusible dye, and in particular, it is preferable to use a diffusible dye-donating substance that forms or releases a diffusible dye by a coupling reaction. It is preferable to use a compound that

Diffusible dye-providing substances that can be used in the present invention will be explained below. The diffusible dye-donor substance may be one that is capable of forming or releasing a diffusible dye as a function of the reduction reaction of the photosensitive silver halide and/or the organic silver salt used if necessary. Depending on their reaction form, they can be classified into negative-type dye-donating substances and positive-type dye-donating substances.

As a negative dye-donating substance, for example, U.S. Pat.
No. 63,079, No. 4,439,513, JP-A-59
-60434, 59-65839, 59-7
No. 1046, No. 59-87450, No. 59-8873
No. 0, No. 59-123837, No. 59-124329
Examples include reducible dye-releasing compounds described in specifications such as No. 59-165054 and No. 59-164055.

Other negative dye-providing substances include, for example, U.S. Pat.
, No. 474,867, JP 59-12431@, 5
No. 9-48765, No. 59-174834, No. 5
No. 9-776642, No. 59-159159, No. 59
Examples include coupled dye-releasing compounds described in specifications such as No. 231040.

Another particularly preferred negative-tone dye-providing substance of the coupled dye-forming compound is one represented by the following general formula (a).

General formula (a) Cp-+J+-+8) In the formula, Cp represents an organic group (coupler residue) that can react with the oxidized form of the reducing agent (coupling reaction) to form a diffusible dye, J represents a divalent bonding group bonded to an active position that reacts with the oxidized form of the reducing agent, and B represents a ballast group. Here, the ballast group is a group that substantially prevents the dye-providing substance from diffusing during heat development processing, and includes groups that exhibit this effect depending on the nature of the molecule (such as a sulfo group),
Refers to groups that exhibit their effects depending on their size (groups with a large number of carbon atoms, etc.). The coupler residue represented by Cp preferably has a molecular weight of 700 or less, more preferably 500 or less, in order to improve the diffusibility of the dye formed.

The ballast group is preferably a group containing 8 or more carbon atoms, more preferably 12 or more carbon atoms, and more preferably a group that is a polymer chain.

The coupled dye-forming compound having a group as a polymer chain is preferably one having a polymer chain having a repeating unit derived from a single m compound represented by the general formula (b) as the above-mentioned group.

General formula (b) Cp -f J-)--+Y +V-fZ 'r-f
L) In the formula, CI) and J have the same meaning as defined in general formula (a), Y represents an alkylene group, arylene group or aralkylene group, ri represents O or 1, and Z is a divalent represents an organic group, and L represents an ethylenically unsaturated group or a group having an ethylenically unsaturated group.

Specific examples of coupling dye-forming compounds represented by general formulas (a) and (b) include JP-A-59-124339
No. 59-181345, No. 60-2950, No. 61-57943, No. 61-59336, etc., U.S. Patent Nos. 4.631,251 and 4,650.
．． No. 748, US Patent No. 4,656,124, and in particular US Patent No. 4.656.
No. 124, U.S. Patent No. 4.631.251, No. 4,6
Preferred are the polymeric dye-providing materials described in Applicant No. 50,748.

As a positive dye-donating substance, for example, JP-A-59-
No. 55430, No. 59-165054, No. 59-
No. 154445, No. 59-766954, No. 5911
No. 6655, No. 59-124327, No. 59-152
Examples include compounds described in publications such as No. 440.

These dye-providing substances may be used alone or in combination of two or more kinds. The amount used is not limited and depends on the type of dye-providing substance, whether it is used alone or in combination, and whether the photographic constituent layer of the light-sensitive material of the present invention is a single layer or a multilayer of two or more. However, for example, its use is 0.005 to 50g per 1f, preferably 0.00g per 1f.
It can be used in an amount of 1 g to 10 g.

The dye-providing substance used in the present invention can be incorporated into the photographic constituent layer of the thermal image-sensitive material using any method. M
(e.g., citric acid or nitric acid) or an aqueous solution of a suitable polymer (e.g., gelatin, polyvinyl butyral, polyvinylpyrrolidone, etc.)
It can be used after solid dispersion.

Next, the photosensitive silver halide used in the present invention will be described. Any silver halide can be used, and examples thereof include silver chloride, silver bromide, silver iodide, silver chlorobromide, silver chloroiodide, and silver iodobromide. The photosensitive silver halide can be prepared by any method commonly used in the photographic art.

Furthermore, it is possible to use an emulsion containing grains having a multilayer structure in which the halogen composition of the grains differs on the surface and inside. For example, a silver halide emulsion having core/shell type silver halide grains in which the halogen composition changes stepwise or continuously can be used.

In addition, the shape of photosensitive silver halide is cubic, spherical, 8
It is possible to use materials that have a clear crystal habit, such as a hedron, dodecahedron, and tetradecahedron, or those that do not. This type of silver halide is described in JP-A-60-215948.

Also, for example, JP-A-58-111933, JP-A No. 5811
No. 1934, No. 58-108526, Research Disclosure No. 22534, etc., and each of these crystal planes has a crystal surface that is larger than the other single crystal of this particle. It is also possible to use a silver halide emulsion containing tabular silver halide grains having a large area and an aspect ratio, that is, a ratio of grain diameter to thickness of 5=1 or more.

Further, in the present invention, a silver halide emulsion containing internal latent image type silver halide grains whose surfaces have not been fogged in advance can be used. For internal latent image type silver halide whose surface is not prefogged, for example, U.S. Pat.
．． 592.250, 3,206.313, 3,
No. 317,322, No. 3,511,622, No. 3.4
No. 47,927, No. 3,761,266, No. 3.
703.584, 3.736.140, etc.
It is described in Il.

Internal latent image type silver halide grains whose surfaces are not fogged in advance are silver halide grains in which the sensitivity inside the grain is higher than the sensitivity on the surface of the silver halide grain, as described in each of the above specifications. be. Also, U.S. Patent No. 3.271.15
No. 7, No. 3,447,927 and No. 3,531,
Silver halide emulsions having silver halide grains incorporating polyvalent anode ions as described in US Pat. No. 291, or halogenated emulsions containing dopants as described in U.S. Pat. Silver halide emulsion with weakly chemically sensitized silver grain surfaces, or JP-A-50-852
Silver halide emulsions comprising grains having a layered structure described in publications such as No. 4 and No. 50-38525, and other publications such as JP-A-52-156614 and JP-A-55-12
Silver halide emulsions such as those described in No. 7549 can be used.

The silver halide in the above-mentioned light-sensitive emulsion may have coarse or fine grains, but the preferred grain size is about 0.005 μm to about 1.5 μm, more preferably about 1.5 μm. It is 0.01 μm to 0.5 μm.

In the present invention, as another method for preparing photosensitive silver halide, it is also possible to allow a photosensitive silver salt-forming component to coexist with an organic silver salt described below to form photosensitive silver halide in a part of the organic silver salt. .

These photosensitive silver halides and photosensitive silver salt-forming components can be used in combination in various ways, and the amount used is preferably (1,<10117 to 50 g per 1 volt of support per layer). , more preferably 0.1 to 10g
It is.

The light-sensitive silver halide emulsion may be chemically sensitized by any method in the photographic art.

Further, the photosensitive silver halide emulsion used can be spectral sensitized using a known spectral sensitizing dye to impart sensitivity to blue, green, red, and near-infrared light.

Typical spectral sensitizing dyes that can be used include, for example, cyanine, merocyanine, complex (that is, trinuclear or tetranuclear) cyanine, holobola-cyanine,
Examples include styryl, hemicyanine, oxonol, and the like.

The preferred amount of these sensitizing dyes added is 1 x 1 per mole of photosensitive silver halide or silver halide forming component.
It is 0-6 mol to 1 mol. More preferably, lX10
-5 to 1X10-' moles.

The sensitizing dye may be added at any stage of the preparation of the silver halide emulsion. That is, it may be carried out at any time, such as when silver halide grains are formed, when soluble salts are removed, before the start of chemical sensitization, during chemical sensitization, or after the end of chemical sensitization.

In the heat-developable photosensitive material of the present invention, it is preferable to use various organic silver salts, if necessary, for the purpose of increasing sensitivity and improving developability.

Examples of organic silver salts that can be used in the heat-developable photosensitive material of the present invention include JP-A Nos. 53-4921 and 49-5262.
No. 6, No. 52-141222, No. 53-36224, No. 53-37626, No. 53-37610, as well as U.S. Patent No. 3.330.633, No. 3.794.496, Silver salts of long-chain aliphatic carboxylic acids and silver salts of carboxylic acids having heterocycles, such as silver behenate, α-( 1-phenyltetrazolethio)
Silver acetate, etc., Special Publication No. 44-26582, No. 45-1
No. 2700, No. 45-18416, No. 45-2218
No. 5, JP-A-52-137321, JP-A No. 58-1186
No. 38, No. 58-118639, U.S. Patent No. 4.12
There are silver salts of imino groups described in various publications such as No. 3.274.

Among the above organic silver salts, imino group silver salts are preferred;
Particularly preferred are silver salts of benzotriazole derivatives, more preferably benzotriazole and its derivatives, 5-methylbenzotriazole and its derivatives, sulfobenzotriazole and its derivatives, and N-alkylsulfamoylbenzotriazole and its derivatives.

The organic silver salts used in the present invention may be used alone or in combination of two or more. Alternatively, the silver salt may be prepared in a suitable binder and used as is without isolation.
The isolated product may be used after being dispersed in a binder by an appropriate means. Dispersion means include, but are not limited to, ball mills, sand mills, colloid mills, vibration mills, and the like.

The amount of organic silver salt used in the layer is preferably 0,601 to 500 moles, more preferably 0.1 to 100 moles per mole of photosensitive silver halide. The amount is most preferably 0.3 to 30 moles.

Reducing agent used in the photothermographic material of the present invention (in this specification, the reducing agent brecasa is also included in the reducing agent)
Those commonly used in the field of heat-developable photosensitive materials can be used.

Examples of reducing agents that can be used in the present invention include U.S. Patent Nos. 3,531,286 and 3,761,27
No. 0, the specifications of No. 3,764,328, and RD (
Research Disclosure) No. 12246,
Same N.

15108, same N 0.15127 and JP-A-1987-
No. 27132, U.S. Patent No. 3,342,599,
No. 3.719.492 Specifications, JP-A-53-13
5628 and 57-79035, p-fluorodilene diamine type and p-amine phenol type developing agents, phosphoroamide phenol type, sulfonamide aniline type developing agents, and hydrazone type color developing agents. Main drugs and their brecas, or phenols,
Sulfonamide phenols, or polyhydroxybenzenes, naphthols, hydroxybinaphthyls and methylene bisnaphthols, methylene bisphenols, ascorbic acid, 3-pyrazolidones, and pyrazolones can be used.

Further, the dye-donating substance may also serve as a reducing agent.

As a particularly preferable reducing agent, JP-A-56-146133
N-(p
-N.

N-dialkylamino) phenylsulfamate is mentioned.

Two or more types of reducing agents may be used simultaneously.

The layer in which the reducing agent is used in the heat-developable photosensitive material of the present invention depends on the type of photosensitive silver halide, the type of organic silver salt, and the type of other additives used, and is not necessarily constant. The amount is usually preferably from 0.01 to 1,500 mol, more preferably from 0.1 to 200 mol, per mol of photosensitive silver halide.

Binders that can be used in the heat-developable photosensitive material of the present invention include polyvinyl butyral, polyvinyl acetate,
These include synthetic or natural polymeric substances such as ethyl cellulose, polymethyl methacrylate, cellulose acetate butyrate, polyvinyl alcohol, polyvinyl pyrrolidone, gelatin, gelatin derivatives such as phthalated gelatin, cellulose derivatives, proteins, starch, and gum arabic. can be used alone or in combination of two or more. In particular, it is preferable to use gelatin or a derivative thereof together with a hydrophilic polymer such as polyvinylpyrrolidone or polyvinyl alcohol, and more preferably to use a mixed binder of gelatin and polyvinylpyrrolidone described in JP-A-59-229556. That's true.

The preferred amount of the binder used is usually 0.05 g to 5 liters per support 17, and more preferably 0.2 g to 5 liters.
It is 20o.

In addition, the binder is 01 to 1 g per 1 g of the dye-providing substance.
It is preferable to use 10g, more preferably 0.2~
It is 5g.

The heat-developable photosensitive material of the present invention can be obtained by forming a photographic constituent layer on a support, and examples of the support that can be used here include polyethylene film, cellulose acetate film, polyethylene terephthalate film, and polyethylene terephthalate film. Synthetic plastic films such as vinyl chloride, paper supports such as photographic base paper, printing paper, art paper, cast coated paper, baryta paper and resin coated paper, and electron beam curable resin compositions on these supports. Examples include supports coated with and cured.

When the photothermographic material of the present invention and the photosensitive material are of a transfer type and an image receiving member is used, various heat solvents are preferably added to the photothermographic material and/or the image receiving member.

The thermal solvent is a compound that is liquid during thermal development and promotes thermal development and/or thermal transfer. These compounds include, for example, U.S. Patent No. 3,347,675;
667, No. 959, (RD Research Disclosure) No. 17643 (X■), JP-A-59-2
No. 29556, No. 59-68730, No. 59-842
No. 36, No. 60-191251, No. 60-232
No. 547, so-14241M, so-61-52643
No. 62-78554, No. 62-42153, No. 62-4213, etc., U.S. Patent Box 3, 438.7
No. 76, No. 3,666.477, No. 3.667,
No. 959, each description 1ii, JP-A-51-19525, JP-A No. 53-24829, JP-A No. 53-60223, JP-A No. 58
-118640 and No. 58-198038, and examples of which are particularly useful in carrying out the present invention include urea derivatives such as dimethylurea, diethylurea, phenylurea, etc.), amide derivatives (e.g., acetamide, benzamide, p-toluamide, etc.), sulfonamide derivatives (e.g., benzenesulfonamide, α
-toluenesulfonamide, etc.), polyhydric alcohols (for example, 1,6-hexanediol, 1,2-cyclohexanediol, pentaerythritol, etc.), or polyethylene glycols.

Among the above thermal solvents, water-insoluble solid thermal solvents are particularly preferably used.

Specific examples of the above-mentioned water-soluble heat solvent include, for example, JP-A-62
-136645, 62-139549, 63-
There are those described in Japanese Patent Application No. 53548, Japanese Patent Application No. 63-205228, and Japanese Patent Application No. 63-54113.

Examples of the layer to which a heat solvent is added include a photosensitive silver halide emulsion layer, an intermediate layer, a protective layer, an image receiving layer of an image receiving member, etc., and the heat solvent is added to each layer so as to obtain an effect depending on each layer.

The preferred addition amount of the heat solvent is usually 10% to 500% by weight, more preferably 30% to 200% by weight of the binder amount.
Weight%.

The organic silver salt and the thermal solvent may be dispersed in the same dispersion. The same binder, dispersion medium, and dispersion device as used for making each dispersion can be used.

In addition to the above-mentioned components, the photothermographic material of the present invention may contain various additives, such as a development accelerator, an antifoggant, a base breaker, etc., if necessary.

Examples of the image accelerator include compounds described in JP-A-59-177550, JP-A-59-111636, and JP-A-59-124333@, as well as JP-A-61-159642 and Japanese Patent Application No. 62-203908. It is also possible to use the development accelerator-releasing compound described in 1983-104645, or the metal ion having an electronegativity of 4 or more described in Japanese Patent Application No. 104645/1983.

Antifoggants include, for example, U.S. Patent Box 3,645;
Higher fatty acids described in No. 739, Akira edition, mercuric salts described in Japanese Patent Publication No. 47-11113, JP-A No. 5
1-47419, U.S. Patent No. 3,700,457, Mei 1I1! , Japanese Patent Application Publication No. 1973
Mercapto compound-releasing compounds described in Japanese Patent No. 50725, arylsulfonic acids described in Japanese Patent No. 49-125016, lithium carboxylate salts described in Japanese Patent No. 51-47419, British Patent No. 1,455,271 l1
11. Oxidizing agents described in JP-A No. 50-101019, sulfinic acids or thiosulfonic acids described in JP-A No. 53-19825, 2-thiouracils described in JP-A No. 51-3223, and 2-thiouracils described in JP-A No. 51-26019. Single sulfur, No. 51-42529, No. 51-81124
Disulfide and polysulfide compounds described in Japanese Patent No. 55-93749, rosins or diterpenes described in Japanese Patent No. 51-57435, Japanese Patent No. 51-10433
Polymeric acids having free carboxyl groups or sulfonic acid groups described in US Pat. No. 8, US Pat. No. 4,138,2
Thiazolinthione described in specification No. 65, JP-A-54-
51821, 1,2,4-triazole or 5-mercapto-1,2,4-triazole described in U.S. Patent No. 4,137,079, JP-A-55-1
Thiosulfinate esters described in No. 40883, 1,2゜3,4-thiatriazoles described in No. 55-142331, No. 59-46641, No. 59-5
Dihalogen compounds or trihalogen compounds described in No. 7233, No. 59-57234, and No. 59
- Thiol compound described in Publication No. 111636, No. 60
Hydroquinone derivatives described in -198540 publication,
Examples include a combination of a hydroquinone derivative and a benzotriazole derivative described in JP 60-227255.

Still another particularly preferred antifoggant is disclosed in JP-A No. 6
2-78554, a polymer inhibitor described in JP-A No. 62-121452, and an inhibitor having a ballast group as described in JP-A-62-123456. can be mentioned.

Furthermore, colorless couplers described in Japanese Patent Application No. 62-320599 are also preferably used.

Examples of the base breaker include compounds that release basic substances by decarboxylation upon heating (e.g., guanidinium trichloroacetate), compounds that decompose through reactions such as intramolecular nucleophilic substitution reactions, and release amines, etc. For example, Japanese Patent Application Publication No. 56-130745, Japanese Patent Application Publication No. 56-132332, British Patent No. 2.079.480, and US Patent No. 4.0.
60.420 specification, JP-A-59-157637,
No. 59-166943, No. 59-180537, No. 59-174830, No. 59-195237, No. 6
Examples include base releasing agents described in JP2-108249, JP62-174745, and the like.

In addition, various additives used in heat-developable photosensitive materials as necessary include antihalation dyes, optical brighteners, hardeners, antistatic agents, plasticizers, spreading agents, matting agents, surfactants, It can contain anti-fading agents, etc., and these are specifically described in RD (Research Disclosure) Magazine V01.170. June 1978 No.
No. 17029, JP-A-62-135825, etc.

These various additives may be added not only to the photosensitive layer but also to non-photosensitive layers such as an intermediate layer, a protective layer or a backing layer.

The heat-developable photosensitive material of the present invention contains (a) a photosensitive silver halide, (b) a reducing agent, and (C) a binder, and when used as a color photosensitive material, contains (d) a dye-providing substance. Furthermore, it is preferable to contain (e) organic silver as necessary. Basically, these may be contained in one heat-developable photosensitive layer, but they do not necessarily need to be contained in a single photographic constituent layer. For example, if the heat-developable photosensitive layer is divided into two layers,
The above components (a), (b), (C), and <8> are contained in one heat-developable photosensitive layer, and the dye-providing substance (d) is contained in the other layer adjacent to this photosensitive layer. They may be contained in two or more constituent layers as long as they are in a state where they can react with each other.

Further, the heat-developable photosensitive layer may be divided into two or more layers: a low-sensitivity layer and a high-sensitivity layer, a high-density layer and a low-density layer, or more.

The heat-developable photosensitive material of the present invention has one or more heat-developable photosensitive layers. In the case of full-color photosensitive materials,
Generally, it has three heat-developable photosensitive layers with different color sensitivities, and in each photosensitive layer, dyes with different hues are formed or released by heat development.

Typically, a yellow dye is used in the blue-sensitive layer, a magenta dye is used in the green-sensitive layer, and a cyan dye is used in the red-sensitive layer, but the invention is not limited to this. It is also possible to combine a near-infrared sensitive layer.

The structure of each layer can be arbitrarily selected depending on the purpose, for example, a structure in which a red-sensitive layer, a green-sensitive layer, and a blue-sensitive layer are sequentially formed on a support, or a stomach-sensitive layer is sequentially formed on a support. , a green-sensitive layer, a red-sensitive layer, or a green-sensitive layer, a red-sensitive layer, and a blue-sensitive layer sequentially on the support.

In addition to the heat-developable photosensitive layer, the heat-developable photosensitive material of the present invention may optionally include non-photosensitive layers such as an undercoat layer, an intermediate layer, a protective layer, a filter layer, a backing layer, and a release layer. . To coat the heat-developable photosensitive layer and these non-photosensitive layers on the support, a method similar to that used for coating and preparing general silver halide photosensitive materials can be applied.

The heat-developable photosensitive material of the present invention usually preferably has a
Development can be carried out by simply heating at a temperature range of 0° C. to 200° C., more preferably 100° C. to 170° C., preferably 1 second to 180 seconds, more preferably 1.5 seconds to 120 seconds. Transfer of the diffusible dye to the image-receiving layer may be carried out simultaneously with heat development by bringing the image-receiving member into close contact with the photosensitive surface of the photosensitive material and the image-receiving layer during heat development, or by bringing the image-receiving member into close contact with the passive member after heat development. Alternatively, the transfer may be carried out by supplying water and then applying heat if necessary. Moreover, you may perform preheating in the temperature range of 70 degreeC - 180 degreeC before exposure. Also, JP-A-6O-i43
As described in No. 338 and No. 61-162041, the photosensitive material and the image receiving member may be preheated at a temperature of 80°C to 250°C immediately before thermal development transfer in order to improve their mutual adhesion. good.

Various heating means can be used for the heat-developable photosensitive material of the present invention.

As the heating means, any method that can be applied to ordinary heat-developable photosensitive materials can be used, such as contacting with a heated block or plate, contacting with a heated roller or drum, or passing through a high-temperature atmosphere. Alternatively, high-frequency heating may be used, or furthermore, a conductive layer containing a conductive substance such as carbon black may be provided on the back surface of the photosensitive material of the present invention or the back surface of the image receiving member for thermal transfer, and the Joule heat generated by energization may be utilized. You can also do that. There are no particular restrictions on the heating pattern, such as preheating (breheating) and then reheating, or heating at a high temperature for a short time or at a low temperature for a long time, by continuously increasing the temperature, or by continuously increasing the temperature. It is also possible to lower the heating temperature or to repeat these steps, and discontinuous heating is also possible, but a simple pattern is preferable. Alternatively, a method in which exposure and heating proceed simultaneously may be used.

When the present invention is applied to a transfer type photothermographic material, an image receiving member is used as described above. In this case, the image-receiving layer that can be effectively used in the image-receiving member may be one that has the function of receiving the dye in the heat-developable photosensitive layer released or formed by heat development, such as tertiary amine or quaternary amine. Polymers Containing Ammonium Salts, U.S. Pat. No. 3,709,69
Those described in the specification of No. 0 are preferably used. Typical image-receiving layers for diffusion transfer include those obtained by mixing a polymer containing ammonium salt, tertiary amine, etc. with gelatin, polyvinyl alcohol, etc., and coating the mixture on a support. Another useful dye-receiving material is one made of a heat-resistant organic polymer material having a glass transition temperature of 40 DEG C. or higher and 250 DEG C. or lower, as described in Japanese Patent Application Laid-Open No. 57-207250.

These polymers may be supported on a support as an image-receiving layer, or may themselves be used as a support.

As for polymers, [Polymer Handbook 2nd Edition] (edited by Joy Brandrup and E.H. Inmargat) published by John Willi and Sons (Polymer Handbook 2nd Edition)
ed, (J, Brandrup, E, H.

1 m+nergut edition) John Wiley
&5ons) glass transition temperature 4
Synthetic polymers above 0°C are also useful. - For boat fishing, a molecular weight of 2,000 to 200,000 is useful for the polymeric substance. These polymeric substances may be used alone or in a blend of two or more types, or may be used in combination of two or more types as a copolymer.

A particularly preferable image-receiving layer is JP-A-59-22342
Examples include a layer made of polyvinyl chloride as described in Japanese Patent No. 5 and a layer made of polycarbonate and a plasticizer as described in JP-A-60-19138.

These polymers can also be used as a support and an image-receiving layer (image-receiving member), in which case the support may be formed from a single layer or from multiple layers. good.

As the support for the image receiving member, transparent supports, opaque supports, etc. may be used, but for example, films such as polyethylene terephthalate, polycarbonate, polystyrene, polyvinyl chloride, polyethylene, polypropylene, etc.
and supports containing pigments such as titanium oxide, barium sulfate, calcium carbonate, and talc, baryta paper, resin-coated paper in which thermoplastic resin containing pigments is laminated on paper, and cloth. , glass, metals such as aluminum, etc., and supports prepared by coating and curing electron beam curable resin compositions containing pigments on these supports, and supports containing pigments on these supports. Examples include a support provided with a coating layer. Furthermore, various coated papers such as the cast coated paper described in JP-A-62-283333 are also useful as supports.

In addition, a support is prepared by coating and curing an electron beam curable resin composition containing a pigment on paper, or a support having a pigment coating layer on paper and an electron beam curable resin composition on the pigment coating layer. The resin layer of the support coated with and cured can be used as an image-receiving layer, so it can be used as is as an image-receiving member.

The heat-developable photosensitive material of the present invention is published in RD (Research Disclosure Magazine) No. 15108, JP-A-57-198.
No. 458, No. 57-207250, No. 61-8014
The photothermographic material may be a so-called monosheet type photothermographic material in which a photosensitive layer and an image-receiving layer are formed on the same support, as described in Japanese Patent No. 8.

It is preferable to provide a protective layer on the photothermographic material and image receiving member of the present invention.

Various additives used in the photographic field can be used in the protective layer. The additives include various matting agents, colloidal silica, slipping agents, organic fluoro compounds (especially fluorine surfactants), antistatic agents, ultraviolet absorbers,
High-boiling organic solvents, antioxidants, hydroquinone derivatives,
Polymer latex, surfactants (including polymeric surfactants), hardeners (including polymeric hardeners), organic silver salt particles, non-photosensitive silver halide particles, antifoggants, development accelerators, etc. can be mentioned.

Regarding these additives, please refer to RD (Research Disclosure Magazine) Vol. 170. June 1978 N.
0.17029 and JP-A-62-135825.

EXAMPLES Specific examples of the present invention will be described below. However, it goes without saying that the present invention is not limited to the examples described below.

Example-1 ■ Preparation of silver iodobromide emulsion (Es-1) Silver iodobromide emulsion (El
-1) was adjusted. The seed emulsion has a silver iodide content of 2 mol%.
, average grain size (length of one side of a cube with the same volume. The same applies to the following descriptions) 0.09μ silver iodobromide emulsion (SE-1
) was used.

(Solution A-1) Ossein gelatin 0.459 polyisopropylene-polyethylene oxydisuccinate sodium ester 10% methanol solution 5. O,fi2
8% ammonia water 291112 emulsion (SE-1) 0.071 mol equivalent amount Ion exchange water 1750 yen (solution B-
1) Ossein gelatin 5.0QKBr
2oo,ogK I
5.8 Finish to soolg with Q ion exchange water (Solution C-1) AQ NOa 246.39
28% ammonia water 200.9% Finish to 414t12 with ion-exchanged water (solution D-1) 50% KB, r aqueous solution Required amount for pAO adjustment (solution E-1) 56% acetic acid aqueous solution Required amount for pH adjustment At 40℃, Kaisho 57-92523, Kaisho 57-9252
Using the mixer shown in Specification No. 4, (Solution A-
(Solution B-1) and (Solution C-1) were added to 1) at equal flow rates by a simultaneous mixing method.

During simultaneous mixing, pl-1 was kept constant at 8.0, and a roller tube pump with variable flow rate was used to mix (solution E-1
) was controlled by changing the flow rate.

DAQ was adjusted to 8.8 at the time of starting the addition of (solution B-1) and (solution C-1), and then continuously changed in proportion to the addition range of (solution B-1). The temperature was controlled to be 9.3 at the end of the addition of solution B-1) and solution C-1). The pAg was controlled by changing the flow port of (solution D-1) using a variable flow rate roller tube pump.

(Solution B-1) and (Solution C-1) were added at the maximum allowable speed (critical speed) without generating small particles.
1) When 2961ff was added, 1.0X
10'mol of potassium hexachloroiridate (IV) (K2 1r Cj!s ) was added as an aqueous solution.

Furthermore, the addition of (solution B-1) and (solution C-1) was continued, and (
The process ended when all of the solution C-1) had been added. Subsequently, (solution D-1) (solution E-1) was used to prepare llAg10
．． 4. The pH was adjusted to 6.0, and washing with demineralized water was performed in a conventional manner. After that, after dispersing in an aqueous solution containing ossein gelatin 45.65Q, the total amount was adjusted to 1200% with distilled water, and further using (solution D-1) and (solution E-1),
At 0°C, pAΩ was adjusted to 8.5 and l)H to 5.8.

The emulsion thus obtained (Em-1) was a silver iodobromide emulsion with a silver iodobromide content of 2 mol %, and as a result of electron microscopy M observation, it was found to be monodisperse with an average grain size of 0.25μ. It turned out to be an emulsion.

The shape of the obtained silver iodobromide grains was almost cubic, but the corners and sides were slightly rounded.

■ Preparation of photosensitive silver halide emulsion (a') Preparation of red-sensitive emulsion (R-1) Silver iodobromide emulsion E
l-1300iN was kept warm at 52°C and stirred, and the following sensitizing dye (a>5oa+g and the following sensitizing dye (b) 1
00-g as a 1% methanol solution,
After 10 minutes, 15 μmol of sodium thiosulfate was added as a 0.1% aqueous solution, and after another 60 minutes, 10 μmol of chlorauric acid (O,OS% aqueous solution) and 20 μmol of ammonium thiocyanate (0.1% aqueous solution) were added. was added.Furthermore, the temperature was kept at 52℃ and stirred for the optimum time (
After continuing aging (30-80 minutes), the temperature was lowered to 40℃,
4-hydroxy-6-methyl-1,3,3a, 7-titraazaindene 250 Ω, 1-phenyl-5-mercaptotetrazole 51 (+ and the following antifoggant 5T-
The emulsion was stabilized by adding 25-q of 1 as a 5% methanol solution, and the total amount was adjusted to 540-q with ion-exchanged water. In this way, red-sensitive emulsion R-1 was obtained.

Sensitizing dye (a) Sensitizing dye (b) T-1 (b) Preparation of green-sensitive emulsion (G-1) Silver iodobromide emulsion Em-2 3001172 was kept at 52°C and stirred, followed by the following sensitizing dye. Sensitive dye (C) 150II1g
were added as a 1% methanol solution, and the 10
After 15 μmol of sodium thiosulfate was added as a 0.1% aqueous solution, and after a further 60 minutes, chloroauric acid (0.05 μmol) was added as a 0.1% aqueous solution.
5 μmop (as a 0.1% aqueous solution) and 10 μmop of ammonium thiocyanate (0.1% aqueous solution) were added. After keeping the temperature at 52°C and continuing to age with stirring for 75 minutes, the temperature was lowered to 40°C to obtain 4-hydroxy-6-methyl-1,3,3a.

7-chitraazaindene 250mg, 1-phenyl-5
- Stabilize the emulsion by adding 5 mΩ of mercaptotetrazole and 25 mg of the above antifoggant 5T-1 as a 5% methanol solution, and dilute the total amount to 540 m+2 with ion-exchanged water.
It was prepared as follows.

In this way, green-sensitive emulsion G-1 was obtained.

Sensitizing dye (c) (c) Preparation of infrared-sensitive emulsion (IR-1) Silver iodobromide emulsion E--2 300112 was kept at 52°C and stirred, and the following sensitizing dye (d) 10■ Ω was added as a 0.05% methanol solution, and 25 gg of the following sensitizing dye (e) was added as a 0.01% methanol solution, and 10 minutes later, 15μm09
of sodium thiosulfate as a 0.1% aqueous solution,
After another 60 minutes, chlorauric acid (as an O, OS% aqueous solution) 5
μmoi and ammonium thiocyanate (0.1% aqueous solution) 10μ■o (1) were added.The temperature was kept at 52℃ and continued aging with stirring for 55 minutes.
4-Hydroxy-6-methyl-1,3
The emulsion was stabilized by adding 25 mg of ゜3a, 7-thitraazaindene 250■σ, 1-phenyl-5-mercaptotetrazole 51 (l) and the above antifoggant 5T-1 as a 5% methanol solution, and then diluted with ion-exchanged water. The total amount is 5
It was prepared in 40 minutes.

In this way, infrared-sensitive emulsion IR-1 was obtained.

Sensitizing dye (d'') Sensitizing dye (+3) ■ Preparation of organic silver salt emulsion At 50°C, JP-A No. 57-92523, No. 57-
Using the mixing agitator shown in No. 92524 Mei III,
500 g of modified gelatin in which 90% or more of the amino groups in gelatin have been substituted with phenylcarbamoyl groups, 400 g of ion-exchanged water (hR, 15.3 g of benzotriazole).

Aqueous solution containing 28% ammonia water 841Q (A)
An aqueous solution of 2360 (B) containing benzotriazole 416Q and 28% aqueous ammonia 2821j2
) and silver nitrate aqueous solution (C) were added at equal flow rates by a simultaneous mixing method. I)H during mixing is 9.3, and p during mixing
Ag was controlled at 11. After the addition is complete, a 20% aqueous solution of modified gelatin 10017, in which 90% or more of the amino groups of gelatin are substituted with phenylcarbamoyl groups, is added, and then the pH is adjusted to 5.5 with 56% acetic acid, and the gelatin is precipitated and dissolved. Excess soluble salts were removed. Furthermore, ion-exchanged water 8000-112 was added, I)H was adjusted to 6.0 with a 10% potassium hydroxide aqueous solution, and the mixture was dispersed for 5 minutes. Then, 50 cl of the above-mentioned modified gelatin was added as a 20% aqueous solution, and then 3. Excess soluble salts were removed by precipitation by adjusting p)l to 4.5 with 5N sulfuric acid. Then the pH
was adjusted to 6.0, finished with ion-exchanged water to a total of 14,200 tQ, and dispersed at 50° C. for 300 minutes to prepare an organic silver salt emulsion.

■ Preparation of hot solvent dispersion-1 125g of the following hot solvent was mixed with 0.049 surfactant-1
(Alkanol XC, 5″ manufactured by Yubon) 0,
It was dispersed in a 5% polyvinylpyrrolidone aqueous solution j00tj2 using an alumina ball mill to give 1201p.

Thermal solvent-1 Anti-fouling agent W-1 Polymeric dye-providing substance (1) Surfactant-1 ■-(1) Preparation of dye-providing substance dispersion-1 The following polymeric dye-providing substance (1) 35.5a, 2.4 g of the following color stain preventive agent W-1 was added to 200 mf of ethyl acetate,
- Ethylhexyl) phthalate 10.00 and tricresyl phosphate 10.0 (l), mixed with 124 mN of surfactant -15ffi mass % aqueous solution and 720 mj2 of 6% gelatin aqueous solution, emulsified and dispersed with an ultrasonic homogenizer, and acetic acid After ethyl was distilled off, the total amount was adjusted to 7951 g with ion-exchanged water to obtain dye-providing substance dispersion-1.

■-(2) Dye-donor dispersion liquid-2 Polymer dye-donor substance (2) same as dye-donor dispersion liquid-1 except that the dye-donor substance was changed to the following polymer dye-donor substance (2) ■Reduction Preparation of agent solution The following reducing agent <R-1) 20.0Q, the following reducing agent (R
-2) 13.30, the following surfactant -20.50g
was dissolved in water and adjusted to pH 7.0 to obtain a reducing agent solution of 2501.12.

Reducing agent (R-1) ■-(3) Dye-donor dispersion-3 This is the above-mentioned dye-donor dispersion-1 except that the dye-donor was changed to the following polymeric dye-donor (3).
It was served in the same manner as in the Book of Fr.

Polymer dye-donor substance (3) Reducing agent (R-2) Surfactant-2 N a O-S CHCOOCH2 (CF 2 CF
2)mH[CHI CC00CH-(CF-CF2)nH(,n
``2*or 3) ■ Preparation of Photosensitive Material 1 Using the organic silver salt dispersion, silver halide emulsion, and dye-providing substance dispersion prepared above, multi-IjMI as shown in Table 1 is prepared.
A color photosensitive material 1 was prepared.

Coating is done by applying a backing layer on a support coated with a subbing layer on both sides.
After coating and drying 1 and backing layer-2 between the two layers, apply 3 layers of 1st WJ to 3rd tl on the opposite side.
WA coating and drying were carried out simultaneously, and furthermore, M4 layer to 7th layer were coated simultaneously with 4Fm.

The m1 to 7th layers and backing layers 1 and 2 contain the following surfactant 3 as a coating aid, and each layer contains tetrakis(vinylsulfonylmethyl)methane and potassium taurine as hardeners. Reactants with salt (reaction ratio 1:0.75 (mole ratio)) were each added at a rate of 0.04Q per 1 g of gelatin.

Surfactant-3 Ct Hs Incidentally, in No. 1NJ to No. 71i, the coating liquid was prepared to pl"5 and then applied.

One Elm Three Tables DOP Rainbow-<2-Ethylhexyl) Phthalate TCP
Nitricresyl phosphate and other compounds listed in the table above are shown on the following pages.

Each additive layer represents the coating amount per 1f.

(However, silver halide and benzotriazole silver are the values converted to silver.) Irradiation prevention dye-3 Irradiation prevention dye-1 ■ Preparation of image receiving member The following compound (SA-1) was applied on photographic baryta paper. ), (SA
-2), (TP-1) and (AC-1) were coated with a polyvinyl chloride layer (image receiving layer) to produce an image receiving member.

(SA-1) Ifcetic acid prevention dye-2 (TP-1) (AC-1> HOCH, CH, SCH, CH, SCH, CH, OHO
, 2Q/f (Evaluation of photographic performance) For the photothermographic material 1, He-N was used as a green light source.
e laser (oscillation wavelength 544 nm), He-Ne laser (oscillation wavelength 633 rv) as an infrared light source, '1 GaAs semiconductor laser (oscillation wavelength 78 nm) as an infrared light source.
Scanning exposure was performed using a scanning exposure device each equipped with 0 ns).

FIG. 3 is a block diagram of the above-mentioned scanning exposure MAH.

The image signal IR that controls the infrared light source is input to the semiconductor laser modulation circuit 27, the semiconductor laser 1 is modulated by the output signal 31, and the modulated output light 34 is converged by the lens 2 and passed through the filter 4 and lens 5. As shown, only the infrared light component is reflected by the dichroic mirror 6 in a certain direction of the polygon mirror 19.

Further, the red component laser light 35 outputted from the He-Ne laser 7 passes through the lens 8 and is input to the optical modulator 9, where the light 3 is modulated according to the image signal R controlling the red light.
8, the light 38 passes through the path of the filter 10 and the lens 11, and only the red component light is reflected by the dichroic mirror 12 and mixed with the infrared component light 43 that has passed through the dichroic mirror 6. The light becomes light 44 and enters the dichroic mirror 18. Furthermore, in the same manner as above, the green component laser light 36 outputted from the le-Ne laser 13 passes through the lens 14, is input to the optical modulator 15, and is modulated according to the signal G. The light 39 is output through the filter 16 and the lens 1.
Through path 7, only the green component light is reflected by the dichroic mirror 18, and is guided to the polygon mirror 19 as light 45 mixed with light 44, which is already a mixture of infrared light components and red components. The light scanned by the polygon mirror 19 is subjected to fθ conversion by an fθ lens 20, and is imaged on a photosensitive material 23 via a mirror 21 and a cylindrical lens 22.

As described above, the photosensitive material is exposed to light whose intensity is modulated in accordance with the signals R, G, and IR.

The stage 24 supporting the photosensitive material 23 is installed to be capable of translational movement by the mutual movement of the spur gear 3o provided on the side and the gear 25 provided on the motor 26, thereby transmitting the rotational motion of the motor 26.

Further, the polygon mirror 19 is installed so as to be driven by a polygon mirror drive section 47.

Therefore, in synchronization with the signals R, G, and iR, the motor drive circuit 46 is operated by the signal output from the control signal generator 48 by the input 5YNC signal, and the motor 26 is driven.
The stage 24 is transported. Further, the rotation of the polygon mirror 19 is also controlled. As described above, a two-dimensional image is exposed on the photosensitive material 23.

The main scanning speed Va of the laser beam is the polygon mirror 1.
By changing the rotation speed of 9, the sub-scanning speed vb
can be controlled by changing the conveyance speed of the stage 24.

By condensing the laser beam into a circular beam with a diameter of 80μ, making the scanning width d 80μ, and controlling the main scanning speed va, the average exposure time of the exposure point in one scan is t.
l was set to 0.33 μsec.

The main scanning interval is 2.8 IIlsec. Here, change the sub-scanning speed vb to obtain the sub-scanning pitch! 125μm,
The thickness was changed to 62.5 μm, 31.3 μm, 15.6 μm, and 7.81 μm to 13.91 μm.

Here, each of the IR, R, and G lasers is operated one by one, and the exposure amount is changed stepwise to achieve the heat development #! The photosensitive material I was exposed to light.

Immediately thereafter, they were overlapped with the image receiving member-1 and thermally developed at 145° C. for 70 seconds. Next, quickly peel off the photosensitive material and image receiving member.
On the polyvinyl chloride of the image receiving member, a negative color image corresponding to each exposure was obtained.The reflection density of the transferred negative image was measured using a densitometer (PDA-65, manufactured by Konica ■) using blue light,
Sensitometric measurements were performed for green and red light. Subsequently, the exposure aperture giving the reflection density D=1.5 was determined in units of erQ/Cf, and this was set as E a + ax.

At this time, the exposure "E" is: E -)Xn XAXt + 10 lx (1-A) X
t11: Exposure intensity n: Number of multiple exposures A: Area ratio of the multiple exposed portion to the image forming area tl: Given as one exposure time. Note that when the scanning pitch l is larger than the scanning width d, the exposure amount is the product of the above E and d/l.

Subsequently, the maximum exposure amount E win that provides an image density that is substantially the same as that in the case of no exposure was determined.

Here, for convenience of measurement and calculation, the density of the unexposed area + 0
．． Find the exposure amount that gives a density of 05 as E sin,
The required exposure range was calculated as ΔE-EllaX/Elin. The obtained E wax and ΔE are shown in Table 1 as relative values with the value obtained by the exposure method (■) taken as 1.

By using the image forming method of the present invention, E wax
can be made small, and since E 1n hardly changes at this time, ΔE can be made small. That is, according to the image forming method of the present invention, it is possible to reduce the required exposure amount range, and within a limited modulation method,
Discrimination can be improved.

A conventional color photographic paper was exposed to light using the same exposure mode as in Example 1, and an image was obtained by wet processing. Although it was possible to reduce ΔE by using the exposure method of the present invention, it was only about 0.8 at most, and the effect was smaller than when applied to a photothermographic material.

In addition, when a sample exposed under exposure condition (3) was left in a dark room at room temperature for a certain period of time and then subjected to heat development, the effect of the present invention tended to diminish as ΔE increased as the standing time became longer; It was appropriate to carry out the heat development treatment within minutes.

Example 2 In the exposure apparatus of Example 1, in addition to changing the rotation speed of the polygon mirror 19 and the conveyance speed of the stage 24,
Image formation was performed in the same manner as in Example 1, except that the exposure interval time t2 was varied over a wide range by replacing the f-θ lens 2o, changing the image signal, etc. (Exposure conditions ). Measurement and division were performed in the same manner as in Example-1.

The required exposure range ΔE under each exposure condition is shown in Table 2 as a relative value to the exposure condition (■) of Example-1.

As the interval time between multiple exposures becomes longer, the required exposure range ΔE
It can be seen that the effect of the present invention, which is to reduce ,, -7-Key=2□ Hereinafter, Higashi Wataru Example-3 In Example-2, the beam diameter was further changed, and the single exposure time (tl) was changed. Other than that, image formation was performed in the same manner as in Example-2, and measurement and
I did the calculations.

The required exposure range ΔE under each exposure condition is shown in Table 3 as a relative value with respect to the exposure condition (■) of Example=1.

The effects of multiple exposure are @ and ■, ■ and 0, ■
As can be seen in the comparison between and O, one exposure r
As the distance between R (tl) increases, the effect of multiple exposure becomes smaller, and when (+>ioμsec), the effect of multiple exposure almost disappears.・Motor drive circuit 47...Polygon mirror drive section 48...Control signal generation section a...Main scanning direction b...Sub-scanning direction

Claims (4)

[Claims] (1) On the support, binder, photosensitive silver halide,
In an image forming method in which an image is obtained by exposing a certain point on a photothermographic material having a reducing agent and/or a reducing agent precursor multiple times and then thermally developing it, one exposure time of the point is t_1, and the exposure interval is An image forming method characterized in that, when t_2, t_1≦10 microseconds, and t_2≦1×10^5. (2) The image forming method according to claim (1), wherein the image is formed by scanning exposure. (3) The image forming method according to claim (2), wherein the scanning exposure uses a laser as an exposure light source. (4) The image forming method according to claim (1), wherein thermal development is carried out within 10 minutes after completion of exposure.