JPS5872936A - Heat developable photosensitive material - Google Patents

Abstract

PURPOSE:To extend the latitude in heat development and to maintain the maximum density by forming a heat developable photosensitive layer composed of a reducible org. silver salt, a reducing agent and a binder on a support and adding an alkali metallic salt of a specified fatty acid to the photosensitive layer. CONSTITUTION:A reducible org. silver salt such as silver behenate and a reducing agent such as hydroquinone as oxidation-reduction image forming components are dissolved in xylene or the like, and polyvinyl butyral as a binder is further dissolved to prepare the 1st coating liq. By applying the 1st liq. to a supporting film, the 1st layer is formed. At least 1 kind of salt such as Na salt represented by general formulaI, II or III is added to the 1st coating liq. to prepare the 2nd coating liq., and by applying the 2nd liq. to the 1st layer, a heat developable photosensitive material is obtd. This material has wide latitude in heat development, and the maximum density is hardly lowered even if the material is stored at high temp. and humidity.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat-developable photosensitive material, and in particular contains a thorium salt or a potassium salt of a fatty acid to increase the maximum density and improve heat-development latitude (heating resistance during heat development). The present invention relates to a heat-developable photosensitive feed that has been improved in terms of its stability over time through storage under high temperature and high humidity conditions.

Traditionally used silver halide photography is light sensitive,
Although it is superior to other photographic methods in terms of gradation, etc., the processing steps such as fixing and bleaching are wet, making it complicated to handle. There are many inconveniences to doing so. Many attempts have been made to form images by dry processing in place of the dark silver halide photography method. An image forming method using a heat-developable photosensitive material in which the developing step is performed by heat treatment has been proposed as being particularly superior to conventional image forming methods.

For example, Japanese Patent Publication No. 43-4924 describes a heat-developable photosensitive material comprising silver halide in catalytic contact with an organic silver salt and an organic silver ion. Further, similar methods are described in Japanese Patent Publication No. 44-26582 and Japanese Patent Application Laid-open No. 46-6074. In addition to the above, heat-developable photosensitive materials that are activated and made photosensitive by heat treatment before imagewise exposure, and then heated as a whole to form a developed image after imagewise exposure, and their preparation. A method is proposed. This heat-developable photosensitive material consists of a heat-developable photosensitive element that does not contain silver halide or has no photosensitivity even if it contains silver halide. -29819, Special Publication No. 53-41967
No. 54-5687 and Japanese Patent Publication No. 54-5687.

. Although heat-developable photosensitive materials have the advantage of not requiring a wet process for image formation, their image properties such as force sensitivity and fog density are still inadequate compared to conventionally used silver halide photography. I can't say that. The biggest drawback is that when stored under high temperature and humidity, the image characteristics change, resulting in a decrease in sensitivity and
This causes a decrease in maximum density and the occurrence of fog.

Various methods have been proposed to improve this deficiency. The method using a thiosulfonic acid salt disclosed in Japanese Patent Publication No. 54-44212 is somewhat effective against desensitization due to aging under high temperature and high humidity conditions, but is less effective in reducing the maximum density 111'. The combined use of sulfinic acids and phthalic acids in JP-A No. 51-54428 is effective in preventing fogging caused by storage at high temperature and high humidity, but it is effective in preventing sensitization due to storage at high temperature and high humidity. Prevention of deterioration in color and stability against light after image formation are insufficient.

Accordingly, an object of the present invention is to provide a photosensitive material having a wide thermal development latitude and exhibiting a small decrease in maximum density even when stored under high temperature and high humidity conditions.

Such an object of the present invention is to provide a support with at least (a) an oxidation-reduction image forming component comprising a cyclizable organic silver salt and a reducing agent, and (b) a photosensitive silver halide or (and) a photosensitive halide. A heat-developable photosensitive element 1 in which a heat-developable photosensitive element consisting of a silver-forming component and (C) a binder is formed in a single layer or in multiple layers, in which (d) the following general formulas (I), (■) and (III) are used. This was achieved by containing at least one weight of a compound represented by:

General formula (I) R,-COOM.

In the formula, R1 represents a linear or branched alkyl group, an aralkyl group, or an aralkyl group, and M1 represents sodium or potassium.

General formula (Ill M2O0C-R2-COOM3 General formula (III) M200C-COOM.

In the formula, R2 represents a straight-chain or branched alkylene group or ha alkenylene group, and dove and M3 represent hydrogen, sodium or potassium (provided that M2 and M are never hydrogen at the same time). .

Compounds of general formulas m, (Ill and (In)) used in the present invention are listed, but are not limited to these compounds.

(11CH8COON a (2) CH2= CHCOONa (3) CH3CH2C00Na (4) CR3(CR2)2 COONa(5)
(CH3)2CHCH2COONa+6) CH3
CH2CHCH=CHCOONa(7) CH3(C
,)(2)4COONa(8) CH3(CH2)3
CH(CH3)COONa' (9) CHs (C
R2)6 COONaal CH3(CH2), C
00NaOυ CH3(CH2)t6cOONaU
CH3(CH2)+2COONa93C)(3(C
H2), 4COONa(11C11, (CH2>4CH
=CHCH2CH=CHCCH2), C00NaOf?
CR3 (CR2)+a COONaQ71
CH3(CH2)1BCOONaQI CHs (
CH2) 20 COONaα wound Na0OC-COO
Na eA Na 00 CCH2COONaal)
HOOCCH2CH2COONa@HOOC(
CH2) scOONa(2) CH3CO0K (c) CH2-C(CH3)000K) CH
8(CH,,)3COOK翰 (CH3)3CCOO
H @ CH3CH=CHCH=CHC00KeA
CHs (CHt)4COOK翰 CH3(CH
2) 8C00K (1) CH, (CH2), C00KOη CH3
(CH2CH=CH)3(CH2), C00KO Bu
CHs (CH2)7 CH-(CH2)7 COOK
(B) (,H3(CHt)+gCOOKHCHs
(CH2) 20 C00K (To) KOOCCH=CHCOOK (To) KO
OCCH2COOK C3M HOO(1'cH2CH2COOK(31
1HOOCCH2C(=CH2)COOKKOO
C(CH2)4C00K QI KOOC(CH2)7COOKGll)
HOOC(CH2)8COOK The method and timing of addition of the compound of the present invention are not particularly limited, and examples include a method of surface-adding the compound in a heat-developable photosensitive material coating solution in a state dissolved in an appropriate solvent, or A method may be employed in which a coating solution for an IP-developable photosensitive material is applied to the support I--, dried, and then the surface thereof is immersed in a solution containing the compound of the present invention. The preferred addition range for the compounds of the present invention is:
0.001 mol to 0.2 mol per mol of reducible organic silver salt
molar range, particularly preferably 0.01 moA/~0
．． The range is one tongue.

The heat-developable photosensitive material used in the present invention contains at least an oxidation-reduction image forming component consisting of a reducible organic silver salt and a reducing agent, and a binder, which may be contained in a single layer. Nuclear reducible silver salt and reducing agent in separate layers, or in multiple layers.
It is also possible to form a multilayer structure in which a layer containing a reducible organic silver salt or a reducing agent is provided below the single layer -F or a layer containing a reducible organic silver salt or a reducing agent. This reducible organic silver salt is the silver salt of an organic acid described in Japanese Patent Publication No. 43-4924 and Japanese Patent Application Laid-open No. 46-6074,
Alternatively, it is a silver salt of an organic compound having an imino group or a mercapto group, especially a silver salt of a long chain fatty acid having 12 to 24 carbon atoms, because it is difficult to undergo undesirable changes such as darkening at room temperature and under indoor light. This is preferable.

Specific examples include silver behenate, silver stearate, silver palmitate, silver myristate, silver laurate, silver oleate, and silver hydroxostearate, among which silver behenate is particularly effective. .

Furthermore, the heat-developable photosensitive material according to the present invention has improved image tone,
In order to improve the stability after image formation, it is preferable to use an organic acid. In particular, when fatty acid silver is used as a reducible organic silver salt, it is preferable to contain the same or similar fatty acids alone or in combination. desirable. The amount of these fatty acids used is 255 mol 2
0 molty, and preferably 300 moltyl and 12 molty Q. The reducing agent used in the above-mentioned oxidation-reduction image forming component can be enumerated as divine. In general, it is a developer used for ordinary silver halide photosensitive materials, and in terms of dimensions, it is hydroquinone, methyl, hydroquino/, chlorohydroquinone, methylhydroxynaphthalene/, N,N'-diethyl-P-phenylene. Examples include diamine, aminephenol, ascorbic M, +-phenyl-3-pyrazolidone, etc. In addition to these, 2,2'-methylenebis(6-ternary-butyl-4-methylphenol)
, 4,4'-butylidenebis(6-tert-butyl-3-methylphenol), 4,4'-thiobis(6-
Furthermore, bisnaphthol-based reducing compounds described in JP-A No. 46-6074, or Belgian Patent No. 8 (1251
Examples include sulfonamidophenol compounds such as 4-benzenesulfonamidophenol described in No. 9 specification.

The heat-developable photosensitive element according to the present invention may contain a binder alone or in combination in the layer. Suitable materials for the binder can be hydrophobic or hydrophilic, and transparent or translucent. Specifically, polyvinyl butyral, cellulose acetate butyrate, polymethyl methacrylate, polyvinylpyrrolidone, ethyl cellulose, cellulose acetate, polyvinyl acetate, polyvinyl alcohol, gelatin, and the sulfobetaine repeating unit described in Canadian Patent No. 774054. Examples include those having the following. The amount of binder used is 10% by weight based on the reducible organic silver base.
: 1 to 1" : 10 is preferable, more preferably 4
The heat-developable photosensitive element may contain silver halides, such as silver chloride, silver bromide, silver iodide, silver iodobromide, silver iodobromide, silver iodine, etc. It is necessary to contain silver chloride and silver iodochlorobromide. Particularly fine particles are effective for this halogenated steel, and in order to prepare it, part of the reducible organic silver base is mixed with rosogenated steel-forming components such as ammonium bromide, odor, etc. Lithium chloride, sodium chloride, N-bromocono1
Examples include a method of preparing fine silver halogenide by chlorination with phosphoric acid imide or the like. In addition, a so-called extra-system method of incorporating silver halide can also be used.

Outside of this system...A heat-developable photosensitive material containing silver halide.

The device is described, for example, in Belgian Patent No. 7.74436. That is, in other words, apart from the heat-developable photosensitive element, the photosensitive...silver halide is prepared outside of the oxidation-reduction image-forming components, and then the silver halide is added to the image-forming components after preparation. It is prepared by mixing. Suitable content of silver halide (or silver halide forming component) is preferably 0.001 mol to 0.30 mol per 1 mol of reducible organic silver base, and preferably 1 c.
L < Ii O, 0.15 mol of 01% ru.

Moreover, a suitable color toning agent can be contained.

A toning agent for this purpose is described in U.S. Patent No. 3,080,254.
Phthalazinone or its derivatives described in the specification of No. 1, cyclic imides described in JP-A No. 46-6074, JP-A-Sho 5
This includes the phthalazinedione compounds described in Japanese Patent Publication No. 0-329.27. .

The heat-developable photosensitive element of the present invention can be used in combination with a thermal fog preventive agent (thermal fog refers to the capri of white background in unexposed areas caused by heat-developed images)0
As thermal fog preventive agents, mercury compounds described in Japanese Patent Publication No. 47-11113, 1.2.4-triazole compounds described in Japanese Patent Publication No. 55-42375, and Japanese Patent Application No. 1982-10
Tetrazole compound described in No. 5270.

Examples include benzoic acids described in Japanese Patent Application No. 56-23512 and compounds having a sulfonylthio group described in Japanese Patent Application No. 56-33483.

The heat-developable photosensitive element of the present invention can further contain a development accelerator, a curing agent, an antistatic agent (layer), an ultraviolet absorber, a fluorescent brightener, a filter dye (layer), etc. .

Elements according to the invention may contain suitable spectral sensitizers. Useful sensitizing dyes include xanthine dyes, melonanine dyes, xanthine dyes, especially "Product Licensing Index IVo192, No. 107-1".
10 (published in December 1971) or Belgian Patent No. 772371 is useful.

The heat-developable photosensitive element according to the present invention can be coated on a suitable support F' to obtain a heat-developable photosensitive material. Typical supports include polyethylene, polypropylene, polyethylene terephthalate, polycarbonate-1, synthetic resin films such as cellulose acetate, synthetic paper, paper coated with resin films such as polyethylene, art paper, and paper such as photographic baryta paper. Examples include metal plates (foils) such as metal plates (foils) such as aluminum, synthetic resin films or glass plates having a metal vapor-deposited film by a conventional method.

Hereinafter, the present invention will be explained according to Examples, but the present invention is of course not limited to these.

Example 1 A dispersion liquid was prepared by dispersing Behen #825.9, 200 ml of Goldenrod and 200 ml of n-butanol using a homomixer. Polyvinyl butyral 10.9 was added to this dispersion, stirred and dissolved, and then heated to 65°C with Mg, and then N-promuconophosphate 1.9 dissolved in 25-acetone. Og was added and stirred for 2 hours.Then, the temperature of this dispersion was adjusted to 30°C, and 2°2'-ethylenebis(6-
250 ml of a solution of xylene/butanol (1/1 by volume) of 8% phenol) and 20% polyvinyl butyral, exemplified compound (7)
A 10% methanol solution of 3.94 and 3-ethyl-5-
A 0.1% DMF solution of ((3-methyl-2-thiazolylidene)ethylidene) rhodanine was added sequentially to the first
The coating solution was prepared. This first coating liquid was applied onto photographic base paper using a roll coater. At this time, the dry coating amount was 1 o, o 97 m. Next, on the coating formed by applying the above first coating liquid, a second coating liquid consisting of the following components was applied with a dry coating amount of 1 o, o 97 m. A heat-developable photosensitive material (I) was prepared by coating in layers to give a coating density of 2.51/m''.

Second coating liquid Phthalazinone 25g Cellulose acetate 50. ! ? Acetone 1,000 fnl A heat-developable photosensitive material (n) was prepared in the same manner as the heat-developable photosensitive material m except that exemplified compound (7) was omitted. My father used heat-developable photosensitive materials (11
and fll) were stored for 120 hours at a temperature of 35° C. and a relative humidity of 80% to prepare samples.

For the above samples, "1tAl!" was applied at 400 lux for 10 seconds using a 150W tungsten lamp for enlarging as the light source.
! (Koda, Kuste, Butaplet-ya 2), and thermal development was performed using a heating roller at 130° C. for 7 seconds or 130° C. for 12 seconds to create an image. The maximum density was measured from the obtained image, and the results shown in Table 1 were obtained.

Table-1 As is clear from Table-1, the heat-developable photosensitive material (I) using the compound (7) of the present invention was heat-developable under relatively mild development conditions of 130°C for 7 seconds. It has a higher maximum density than the developable photosensitive material (n). Further, when the development is further advanced at 130° C. for 12 seconds, the heat-developable photosensitive material (1) of the present invention shows less change in the maximum density compared to the maximum density under the developing conditions of 130° C. and 7' seconds. This indicates that the heat-developable photosensitive material (I) of the present invention has a large latitude in heat development. It can also be seen that the heat-developable photosensitive material of the present invention exhibits extremely little decrease in maximum density due to storage over time under high temperature and high humidity conditions.

Example 2 Exemplary compound of the heat-developable photosensitive material (I) of Example 1
) instead of Exemplified Compound 04790m9 to prepare a heat-developable photosensitive material fl), Exemplified Compound Qc9850rn9 to prepare a heat-developable photosensitive material (i), and Exemplified Compound -590■ to prepare a heat-developable photosensitive material (■). , Exemplary Compound @ 620
Example 1
The material was stored over time, processed, and heat developed according to the description given in Table 2, and the results shown in Table 2 below were obtained.

As a comparative sample, the heat-developable photosensitive material of Example 1 (1) was used.

Table 2 As is clear from Table 2, by using the compound of the present invention, it is possible to obtain a heat developable photosensitive material that has a wider heat development latitude and has excellent storage stability under high temperature and daylight conditions. I understand.

Example 3 Silver behenate 25&, behenic acid 20! j, Kinren 3
25 ml and 325 gnl of n-butanol were dispersed using a homomixer to prepare a dispersion. Polyvinyl butyral 4. , Og were added and dissolved with stirring. Thereafter, the temperature was heated to 50°C, and 0.259% of lithium bromide dissolved in methanol 50- was added, and stirring was continued for 2 hours.Then, the temperature was adjusted to 30°C, and a 10 weight percent methanol solution of exemplified compound ◇η 5 .4tnt was added to prepare the first coating solution.Then, this first coating solution was applied using a roll coater so that the dry coating amount was 7.09/co.Furthermore, the following second coating solution was applied. Application amount when dry: 5.25g/
A heat-developable photosensitive material (5) was prepared.

212'~methylenebis(6-[-)゛thyl-4-methylph, mer) 50g phthalazinone
159 body sensitizing dye
0.01g polyvinyl butyral 40j
J Ki/Ren 500 ydn-butanol 500i tert-ethyl-5-(
A heat-developable photosensitive material (4) was prepared in the same manner as in the heat-developable photosensitive material MO, except that (3-methyl-2-thiazolilidene)ethylidene]rhodanine and Exemplary Compound 0 were omitted. Storage and exposure over time as described in Example 1;
Heat development was performed. However, heat development was carried out at 125°C for 7 seconds or at 125°C for 12 seconds. Table of results obtained.
Shown in 3.

Table 3 As is clear from Table 3, the exemplary compound of the present invention (1t
It can be seen that the pP imageable photosensitive material MAL using J has a greater thermal development latitude than the comparative heat-developable photosensitive material tyfJO1, and the decrease in maximum density after static storage is extremely small.

patent applicant Oriental Photo Industry Co., Ltd.

Claims (1)

[Scope of Claims] At least (a) an oxidation-reduction image-forming component comprising a reducible organic silver salt and a reducing agent, (b) a photosensitive silver halide or (and) a photosensitive silver halide formed on a support. In a heat-developable photosensitive material in which a heat-developable photosensitive element consisting of a component and (C) a binder is formed into a single layer or a multilayer, the heat-developable photosensitive material has (d) the following general formula (IL (n) or C
A heat-developable photosensitive material characterized by containing at least one compound represented by II) General formula (■) R, -COOM. In the formula, R1 represents a straight-chain or branched alkyl group, alkenyl group or aralkyl group, and Ml represents sodium or potassium. General formula (Il) M2O0C-R2-C00M3 - General formula fl[11 M2O0C-C00M3 In the formula, R2 represents a linear or branched alkylene group or alkenylene group, and M2 and M3 represent hydrogen, sodium or potassium (provided that M2 and M3 cannot be hydrogen at the same time).