JP3832946B2 - Thermal image forming material coating method, thermal image forming layer coating solution, thermal image forming material and photosensitive heat-developable image forming material - Google Patents

Abstract

In a process for the preparation of a thermographic imaging element, a coating solution containing an organic silver salt and a binder is applied. The coating solution should have a viscosity at 25 DEG C of 500-500,000 mPa.s at a shear rate of 0.1 s<-1> and 0.1-100 mPa.s at a shear rate of 1,000 s<-1>. A coating free of streaks and wind-swept variations can be formed at a high speed. Thermographic and photothermographic imaging elements having improved surface quality and a satisfactory imaging capability are obtained.

Description

【０１０５】
実施例２：熱画像形成材料
《ハロゲン化銀粒子の調製》
水700mlにフタル化ゼラチン22gおよび臭化カリウム30mgを溶解して温度35℃にてpHを5.0に合わせた後、硝酸銀18.6gおよび硝酸アンモニウム0.9gを含む水溶液159mlと臭化カリウムおよび沃化カリウムを92:8のモル比で含む水溶液をpAg7.7に保ちながらコントロールダブルジェット法で10分間かけて添加した。ついで、硝酸銀55.4gおよび硝酸アンモニウム2gを含む水溶液476mlおよび六塩化イリジウム酸二カリウムを10μモル/リットルと臭化カリウムを1モル/リットルで含む水溶液pAg7.7に保ちながらコントロールダブルジェット法で30分間かけて添加した後、4-ヒドロキシ-6-メチル-1,3,3a,7-テトラザインデン1gを添加し、さらにpHを下げて凝集沈降させ脱塩処理をした。その後、フェノキシエタノール0.1gを加え、pH5.9、pAg8.2に調製し沃臭化銀粒子(沃素含量コア8モル%、平均2モル%、平均サイズ0.05μm、投影面積変動係数8%、(100)面比率85%の立方体粒子)の調製を終えた。
【０１０６】
こうして得たハロゲン化銀粒子を60℃に昇温して銀1モル当たりチオ硫酸ナトリウム85μモルと2,3,4,5,6-ペンタフルオロフェニルジフェニルフォスフィンセレニドを11μモル、15μモルのテルル化合物、塩化金酸3μモル、チオシアン酸270μモルを添加し、120分間熟成した後40℃に急冷したのち、100μモルの色素、500μモルの2-メルカプト-5-メチルベンゾイミダゾールを添加し30℃に急冷してハロゲン化銀乳剤を得た。
【０１０７】
《有機ポリハロゲン化物分散物の調製》
トリブロモメチルフェニルスルホン50gとヒドロキシプロピルセルロース10gに水940gを添加し良く混合してスラリーとした。平均直径0.5mmのジルコニアビーズ840ｇ用意してスラリーと一緒にベッセルに入れ、分散機（1／4Ｇサンドグラインダーミル：アイメックス（株）製）にて5時間分散し有機ポリハロゲン化物分散物を得た。
【０１０８】
《乳剤層塗布液の調製》実施例１で得た有機銀塩分散物100g、還元剤分散物20g 、および上記有機ポリハロゲン化物分散物15g、ラックスター3307B(大日本インキ化学工業（株）製；SBRラテックス）20ｇ、上記ハロゲン化銀乳剤10gと表2の粘度となる量の水をよく混合し乳剤層塗布液を調製した。
【０１０９】
《乳剤面保護層塗布液の調製》
イナートゼラチン100ｇに対し、270mg のスルホコハク酸ジ(2-エチルヘキシル)エステルナトリウム塩860mg、ポリメチルメタクリレート微粒子（平均粒径サイズ2.5μm）0.8ｇ、フタラジン5.3g、4-メチルフタル酸10g、硫酸アルミニウム4.2g、硫酸カリウムクロム(III)12水和物0.8gに水を総量1600ccとなるよう添加し表面保護層塗布液とした。
【０１１０】
《バック層塗布液》
固体塩基であるN,N,N,N-テトラエチルグアニジンと4-カルボキシスルフォニル-フェニルスルフォンのモル比1：2の塩10gをポリビニルアルコール10g、水88gと1/16Gサンドグラインダーミル(アイメックス(株)製)で分散し塩基液を得た。
【０１１１】
塩基性染料前駆体2.1g、酸性物質7.9g、染料0.1g、酢酸エチル10gを混合溶解した有機溶媒相をポリビニルアルコール10gおよび水80gからなる水溶液相にに混合し、常温で乳化分散し染料液を得た(平均粒径2.5μm)。
【０１１２】
こうして得た塩基液39g、染料液26g、ポリビニルアルコール10wt%水溶液36gを混合しバック面塗布液を得た。
【０１１３】
《バック面保護層塗布液》
ゼラチン20g、ポリメチルメタクリレート(平均粒径7μm)0.6g、ドデシルベンゼンスルホン酸ナトリウム0.4g、X-22-2809(信越シリコーン(株)製シリコーン化合物)1gを水480gに溶解しバック面保護層塗布液を得た。
【０１１４】
《熱画像形成材料の調製》
ラックスター3307Bならびにゼラチンで下塗りされた175μmポリエチレンテレフタレート支持体にバック層塗布液を647nmの光学濃度が0.7となる流量で、バック面保護層塗布液を50g/m²同時重層塗布した後、バック面と反対の面に乳剤層塗布液を塗布銀量1.8g/m²となるように塗布し30℃40%RH風速20m/secの風で乾燥したのち、乳剤面保護層塗布液をゼラチン量2.2g/m²となるように塗布した。こうして得られた感光材料の平滑度(J.TAPPI紙パルプ試験法No.5記載の王研式平滑度測定を用いベック平滑度を調べた)は乳剤面1200秒、バック面85秒であった。
【０１１５】
【化１】

【０１１６】
(面状の評価)
得られた塗布物の面状を塗布幅10cm当たりに発生したスジの本数および風ムラの状態を塗布物の銀量の最大値と最小値の差(g/m²)で評価した。
【０１１７】
(写真性能の評価)
647nmKrレーザー感光計(最大出力500mW)で法線に対して30度の斜度で写真材料を露光した後、写真材料を120℃で15秒間処理(現像)し、得られた画像の評価を濃度計により行った。測定の結果は、Dmin、感度(Dminより1.0高い濃度を与える露光量の比の逆数)で評価した。感度については写真材料3の感度を100とした。
【０１１８】
結果を表2に示す。本発明の領域で面状、写真性能いずれも良好であることがわかる。
【０１１９】
【表２】

【０１２０】
実施例３
実施例２の感光材料4の乳剤層塗布液にN-(2-メトキシフェニル)-N-ホルミルヒドラジンを塗布量1mg/m²となるように添加したところ良好な面状と写真性能を得た。
【０１２１】
実施例４
実施例２の感光材料4において乳剤層塗布液中のハロゲン化銀を添加せず、還元剤分散物の代わりに等モルの3,4-ジヒドロキシ安息香酸メチルを水溶液で添加し、さらにバック面の塩基液ならびに染料液を添加しなかったものを感熱材料とした。こうして得た感熱材料に対して90℃5秒で加熱し面状と色調を評価したところ良好な性能を示すことがわかった。
【０１２２】
【発明の効果】
本発明により、面状が良好で画像形成能力に優れた熱画像形成材料が得られる。
【図面の簡単な説明】
【図１】実地例１で用いたコーターの一部を破断して示す正面図である。
【符号の説明】
１ 支持体
２ 塗布バックアップロール
３ コーティングダイ
４ 塗布液
５ 減圧室
Ａ チリングゾーン[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a thermal image forming material coating method, a thermal image forming layer coating solution, a thermal image forming material, and a photosensitive heat-developable image forming material.
[0002]
[Prior art]
In recent years, in the medical field, reduction of waste processing liquid has been strongly desired from the viewpoint of environmental protection and space saving. Therefore, the photosensitive heat for medical diagnosis and photographic technology can be efficiently exposed by a laser image setter or a laser imager, and can form a clear black image having high resolution and sharpness. There is a need for techniques relating to developed photographic materials. These photosensitive photothermographic materials can eliminate the use of solution processing chemicals and supply customers with a simpler heat development processing system that does not damage the environment.
[0003]
Although there is a similar requirement in the field of general imaging materials, medical images are required to have fine image quality because they require fine depiction. There is a feature that a black tone image is preferred. At present, various hard copy systems using pigments and dyes such as inkjet printers and electrophotography are generally distributed as modeling systems, but there is no satisfactory output system for medical images.
[0004]
On the other hand, thermal imaging systems using organic silver salts are disclosed in many documents including US Pat. No. 2910377 and Japanese Patent Publication No. 43-4924. Thermal image forming systems using these organic silver salts can achieve image quality and color tone that are satisfactory as medical images, but the fluidity of the coating liquid is high and surface defects (wind unevenness) occur due to wind during drying. There is an easy problem. In addition, if the coating solution is highly viscous so that wind unevenness does not occur, the coating property is remarkably deteriorated and a streak failure occurs. In order to make these failures compatible, it is usually handled by lowering the drying air speed, but the drying ability is impaired and the high-speed coating property is lost.
[0005]
On the other hand, conventional photographic materials solve such problems by using gelatin as a binder and rapidly cooling after application to gelation. However, when gelatin is used in the image forming layer of the thermal image forming material and the same means is used, substance diffusion in the heated state does not occur and image formation is significantly impaired.
[0006]
[Problems to be solved by the invention]
An object of the present invention is to provide a thermal image forming material coating method, a thermal image forming layer coating solution, a thermal image forming material, and a photosensitive heat-developable image forming material that have good surface shape and excellent high-speed coating properties without impairing image forming ability Is to provide.
[0007]
[Means for Solving the Problems]
This object has been achieved by the following means.
(1) A liquid containing an organic silver salt and a binder , wherein 50 wt% or more of the binder is a polymer latex, and 30 wt% or more of the solvent of the liquid is water, and the viscosity at 25 ° C. 500 mPa · s or more 500,000 mPa · s or less, and a method of applying a thermal imaging material to be applied is set lower than 0.1 mPa · s or higher 100 mPa · s at shear velocity of 1000S ^-1, the viscosity at a shear rate 0.1 s ^-1.
(2) The method for applying a thermal image forming material according to (1), wherein the liquid further contains a silver ion reducing agent.
(3) The method for applying a thermal image forming material according to (1) or (2), wherein the organic silver salt is an organic carboxylic acid silver salt.
(4) wherein the liquid further comprises a photosensitive silver halide (1) to (3) the method of applying any of the thermal imaging material.
(5) organic silver salt, a binder and reducing agent for silver ion a including thermal imaging layer coating liquid, more 50 wt% of the binder is polymer latex, 30 wt of solvents of the thermal image forming layer coating solution % or more is water, a viscosity at 25 ° C., and at 500 mPa · s or more 500,000 mPa · s or less at a shear rate of 0.1 s ^-1, and 0.1 mPa · s or higher 100 mPa · s or less at shear velocity of 1000S ^-1, the viscosity A thermal image forming layer coating solution.
(6) an organic silver salt, a binder and reducing agent for silver ion a including thermal imaging layer coating liquid, more 50 wt% of the binder is polymer latex, 30 wt of solvents of the thermal image forming layer coating solution % or more is water, and a viscosity at 25 ° C. or less 500 mPa · s or more 500,000 mPa · s at a shear rate 0.1 s ^-1, and at a shear rate 1000 s ^-1 0.1 mPa · s or higher 100 mPa · s or less A thermal image forming material having a thermal image forming layer coated with a thermal image forming layer coating solution.
(7) an organic silver salt, a binder, a silver ion reducing agent and a photosensitive silver halide A including thermal imaging layer coating liquid, more 50 wt% of the binder is a polymer latex, said thermal imaging layer a 30 wt% or more of water solvent of the coating solution, a viscosity at 25 ° C. and at 500 mPa · s or more 500,000 mPa · s or less at a shear rate of 0.1 s ^-1, and 0.1 mPa · s or higher at shear velocity of 1000S ^-1, the viscosity A photosensitive heat-developable image-forming material having a thermal image-forming layer coated using a thermal image-forming layer coating solution of 100 mPa · s or less.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
The present invention is described in detail below.
The organic silver salt that can be used in the present invention is relatively stable to light, but is 80 ° C. or higher in the presence of an exposed photocatalyst (such as a latent image of photosensitive silver halide) and a reducing agent. It is a silver salt that forms a silver image when heated above. The organic silver salt may be any organic material containing a source capable of reducing silver ions. Silver salts of organic acids, especially silver salts of organic carboxylic acids, particularly silver salts of long-chain aliphatic carboxylic acids (having 10 to 30, preferably 15 to 28 carbon atoms) are preferred. Preference is also given to organic or inorganic silver salt complexes in which the ligand has a complex stability constant in the range of 4.0 to 10.0. The silver supply material can preferably constitute about 5 to 70% by weight of the imaging layer. Preferred organic silver salts include silver salts of organic compounds having a carboxyl group. Examples of these include, but are not limited to, silver salts of aliphatic carboxylic acids and silver salts of aromatic carboxylic acids. Preferred examples of the aliphatic carboxylic acid silver salt include silver behenate, silver arachidate, silver stearate, silver oleate, silver laurate, silver caproate, silver myristate, silver palmitate, silver maleate and fumarate. Silver acid, silver tartrate, silver linoleate, silver butyrate and silver camphor, mixtures thereof, and the like.
[0009]
Silver salts of compounds containing a mercapto group or a thione group and derivatives thereof can also be used. Preferred examples of these compounds include silver salt of 3-mercapto-4-phenyl-1,2,4-triazole, silver salt of 2-mercaptobenzimidazole, silver salt of 2-mercapto-5-aminothiadiazole, 2 Silver salt of thioglycolic acid such as silver salt of-(ethylglycolamide) benzothiazole, silver salt of S-alkylthioglycolic acid (wherein the alkyl group has 12 to 22 carbon atoms), silver salt of dithioacetic acid, etc. Silver salt of dithiocarboxylic acid, silver salt of thioamide, silver salt of 5-carboxyl-1-methyl-2-phenyl-4-thiopyridine, silver salt of mercaptotriazine, silver salt of 2-mercaptobenzoxazole, US Patent No. Silver salts described in US Pat. No. 4,123,274, silver salts of 1,2,4-mercaptothiazole derivatives such as silver salts of 3-amino-5-benzylthio-1,2,4-thiazole, and the like described in US Pat. 3- (3-carboxyethyl) -4- Include silver salts of thione compounds such as silver salt of chill-4-thiazoline-2-thione. Furthermore, a compound containing an imino group can also be used. Preferred examples of these compounds include silver salts of benzotriazole and derivatives thereof, for example, silver salts of benzotriazole such as silver methylbenzotriazole, silver salts of halogen-substituted benzotriazole such as silver 5-chlorobenzotriazole, US Patent 1,2,4-triazole or silver salt of 1-H-tetrazole as described in US Pat. No. 4,220,709, and silver salts of imidazole and imidazole derivatives. For example, various silver acetylide compounds described in US Pat. Nos. 4,761,361 and 4,775,613 can also be used.
[0010]
Although there is no restriction | limiting in particular as a shape of the organic silver salt which can be used for this invention, The acicular crystal | crystallization which has a short axis and a long axis is preferable. In the present invention, the minor axis is preferably 0.01 μm to 0.20 μm, the major axis is 0.10 μm to 5.0 μm, the minor axis is 0.01 μm to 0.15 μm, and the major axis is 0.10 μm to 4.0 μm. The particle size distribution of the organic silver salt is preferably monodispersed. Monodispersion is preferably 100% or less, more preferably 80% or less, and even more preferably 50% of the value obtained by dividing the standard deviation of the lengths of the short and long axes by the short and long axes, respectively. It is as follows. The method for measuring the shape of the organic silver salt can be determined from a transmission electron microscope image of the organic silver salt dispersion. As another method for measuring monodispersity, there is a method for obtaining the standard deviation of the volume-weighted average diameter of the organic silver salt, and the 100 fraction (coefficient of variation) of the value divided by the volume-weighted average diameter is preferably 100% or less. More preferably, it is 80% or less, and further preferably 50% or less. As a measuring method, for example, it is obtained from the particle size (volume load average diameter) obtained by irradiating the organic silver salt dispersed in the liquid with laser light and obtaining the autocorrelation function for the time change of the fluctuation of the scattered light. Can do.
[0011]
The organic silver salt that can be used in the present invention can be preferably desalted. There is no particular limitation on the method for performing desalting, and a known method can be used, but a known filtration method such as circular filtration, suction filtration, ultrafiltration, and flock-forming water washing by agglomeration method can be preferably used. .
[0012]
For the purpose of obtaining fine particles having a small particle size and no aggregation, the organic silver salt that can be used in the present invention is a method of forming a solid fine particle dispersion using a dispersant. The method of dispersing the organic silver salt in the form of solid fine particles is carried out in the presence of a dispersion aid by known finer means (for example, ball mill, vibration ball mill, planetary ball mill, sand mill, colloid mill, jet mill, roller mill, microfluidizer, Nanomizer, Gaurin homogenizer) can be mechanically dispersed, and a microfluidizer, Nanomizer, and Gaurin homogenizer are preferably used.
[0013]
When organic silver salt is made into solid fine particles using a dispersant, for example, polyacrylic acid, acrylic acid copolymer, maleic acid copolymer, maleic acid monoester copolymer, acryloylmethylpropane sulfonic acid Synthetic anionic polymers such as copolymers, semi-synthetic anionic polymers such as carboxymethyl starch and carboxymethyl cellulose, anionic polymers such as alginic acid and pectinic acid, anions described in JP-A-52-92716, WO88 / 04794, etc. Surfactants, compounds described in Japanese Patent Application No. 7-350753, or known anionic, nonionic, cationic surfactants, and other polyvinyl alcohol, polyvinyl pyrrolidone, carboxymethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methylcellulose Known polymers such as Alternatively, a polymer compound existing in nature such as gelatin can be appropriately selected and used.
[0014]
Dispersing aid is generally mixed with organic silver salt powder or wet cake organic silver salt before dispersion, and sent to the disperser as a slurry. It is good also as an organic silver salt powder or a wet cake by heat-treating and the process by a solvent. The pH may be controlled with an appropriate pH adjusting agent before or during dispersion.
[0015]
In addition to mechanical dispersion, it may be coarsely dispersed in a solvent by controlling the pH, and then finely divided by changing the pH in the presence of a dispersion aid. At this time, an organic solvent may be used as a solvent used for the coarse dispersion, and the organic solvent is usually removed after the formation of fine particles.
[0016]
The prepared dispersion is stored with stirring for the purpose of suppressing sedimentation of fine particles during storage, or stored in a highly viscous state (for example, in a gelatinized state using gelatin) with a hydrophilic colloid. You can also In addition, a preservative can be added for the purpose of preventing the propagation of various germs during storage.
[0017]
The organic silver salt of the present invention can be used in a desired amount, preferably 0.1-5 g / m ² as silver amount, more preferably from 1 to 3 g / m ^2.
[0018]
The organic silver salt-containing liquid or the thermal image forming layer coating liquid in the present invention is a so-called thixotropic fluid. Thixotropy refers to the property that the viscosity decreases as the shear rate increases.
[0019]
Although any apparatus may be used for the viscosity measurement of the present invention, an RFS fluid spectrometer manufactured by Rheometrics Far East Co., Ltd. is preferably used and measured at 25 ° C.
[0020]
In the present invention, the viscosity of the organic silver salt-containing liquid or thermal image forming layer coating solution is 500 mPa · s or more and 500,000 mPa · s or less, preferably 500 mPa · s or more and 300,000 mPa · s or less, more preferably at a shear rate of 0.1 S- ¹ . Is from 1,000 mPa · s to 100,000 mPa · s, particularly preferably 30,000 mPa · s or less. In addition, at a shear rate of 1000 S- ^1, it is 0.1 mPa · s to 100 mPa · s, preferably 0.2 mPa · s to 100 mPa · s, more preferably 1 mPa · s to 80 mPa · s. The coating solution of the heat-developable light-sensitive material using the conventional conventional photographic light-sensitive material and the silver benzotriazole salt is 20~100mPa · s, of about 5 to 50 mPa · s at 1000 S ^-1 at 0.1 S ^-1, behenic In the photothermographic material using an acid silver salt, 0.1S- ¹ and 1000S- ¹ were about 100 to 300 mPa · s, and none of them was a liquid having thixotropic properties.
[0021]
Various systems that exhibit thixotropic properties are known, and are described in “Lectures / Rheology” edited by Polymer Publishing Co., “Polymer Latex” (published by Polymer Publishing Co., Ltd.) co-authored by Muroi and Morino. In order to develop thixotropy in a liquid, it is necessary to contain a large amount of solid fine particles. In order to enhance the thixotropy, it is effective to contain a thickening linear polymer, the solid fine particles contained therein are anisotropic and increase the aspect ratio, alkali thickening, use of a surfactant, and the like.
[0022]
In the present invention, in particular, solid fine particles having a size of 10 μm or less and 0.001 μm or more, preferably 5 μm or less and 0.01 μm or more are contained in an organic silver salt-containing liquid or thermal image forming layer coating solution in an amount of 10 wt% to 80 wt%, preferably 15 wt%. % To 50 wt% or less, more preferably 20 wt% to 50 wt%. Especially, it is preferable that at least 1 type of this solid fine particle is not spherical shape, but is flat form or needle shape. Further, the non-spherical solid fine particles are preferably contained in an amount of 0.1 wt% to 50 wt%, particularly preferably 0.5 wt% to 20 wt%. Examples of the solid fine particles include solid fine particles such as organic silver salts, reducing agents, binders and antifoggants.
[0023]
The organic silver salt-containing liquid or thermal image forming layer coating liquid of the present invention preferably contains a reducing agent for the organic silver salt. The reducing agent for the organic silver salt may be any substance, preferably an organic substance, that reduces silver ions to metallic silver. Conventional photographic developers such as phenidone, hydroquinone and catechol are useful, but hindered phenol reducing agents are preferred. The reducing agent is preferably contained in an amount of 5 to 50% by mole, more preferably 10 to 40% by mole, based on 1 mole of silver on the surface having the image forming layer. The reducing agent may be a so-called precursor that is derivatized so as to have an effective function only during development.
[0024]
In photothermographic materials using organic silver salts, a wide range of reducing agents are disclosed in JP-A-46-6074, 47-1238, 47-33621, 49-46427, 49-115540, 50-14334, 50-36110, 50-147711, 51-32632, 51-1023721, 51-32324, 51-51933, 52-84727, 55- 108654, 56-146133, 57-82828, 57-82829, JP-A-6-3793, U.S. Patent 3,667,9586, 3,679,426, 3,751,252, 3,751,255, 3,761,270 No. 3,782,949, No. 3,839,048, No. 3,928,686, No. 5,464,738, German Patent No. 2321328, European Patent No. 692732, and the like. For example, amidooximes such as phenylamidooxime, 2-thienylamidooxime and p-phenoxyphenylamidooxime; azines such as 4-hydroxy-3,5-dimethoxybenzaldehyde azine; 2,2-bis (hydroxymethyl) propionyl- a combination of an aliphatic carboxylic acid aryl hydrazide such as a combination of β-phenylhydrazine and ascorbic acid and ascorbic acid; a combination of polyhydroxybenzene and hydroxylamine, reductone and / or hydrazine (eg hydroquinone and bis (ethoxyethyl) ) Such as combinations of hydroxylamine, piperidinohexose reductone or formyl-4-methylphenylhydrazine); such as phenylhydroxamic acid, p-hydroxyphenylhydroxamic acid and β-arininhydroxamic acid Droxamic acid; a combination of azine and sulfonamidophenol (for example, phenothiazine and 2,6-dichloro-4-benzenesulfonamidophenol); ethyl-α-cyano-2-methylphenyl acetate, ethyl-α-cyanophenyl acetate Α-cyanophenylacetic acid derivatives such as 2,2-dihydroxy-1,1-binaphthyl, 6,6-dibromo-2,2-dihydroxy-1,1-binaphthyl and bis (2-hydroxy-1-naphthyl) methane A combination of bis-β-naphthol and a 1,3-dihydroxybenzene derivative (such as 2,4-dihydroxybenzophenone or 2,4-dihydroxyacetophenone); 5-pyrazolones such as 1-phenyl-5-pyrazolone; dimethylaminohexose reductone, anhydrodihydroaminohexose reductone and anhydride Reductone as exemplified by dihydropiperidone hexose reductone; sulfonamide phenol reducing agents such as 2,6-dichloro-4-benzenesulfonamidophenol and p-benzenesulfonamidophenol; 2-phenylindane-1,3 Chromans such as 2,2-dimethyl-7-t-butyl-6-hydroxychroman; 1,4-dihydropyridines such as 2,6-dimethoxy-3,5-dicarboethoxy-1,4-dihydropyridine Bisphenols (eg 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) -3,5,5-trimethylhexane and 2,2-bis (3,5-dimethyl) -4-hydroxyphenyl) propane); ascorbic acid derivatives ( For example, 1-ascorbyl palmitate, ascorbyl stearate); and aldehydes and ketones such as benzyl and biacetyl; 3-pyrazolidone and certain indan-1,3-diones; chromanol (such as tocopherol). Particularly preferred reducing agents are bisphenol and chromanol.
[0025]
The reducing agent of the present invention may be added by any method such as a solution, a powder, or a solid fine particle dispersion. The solid fine particle dispersion is performed by a known finer means (for example, ball mill, vibrating ball mill, sand mill, colloid mill, jet mill, roller mill, etc.). A dispersion aid may be used when dispersing the solid fine particles.
[0026]
The organic silver salt-containing liquid or a thermal imaging layer coating solution of the present invention contains a port Rimmer latex least 50 wt% of the total binder. Hereinafter, the image forming layer obtained by applying the organic silver salt-containing liquid or the thermal image forming layer coating liquid of the present invention is referred to as “the image forming layer of the present invention”, and the polymer latex used as the binder is referred to as “the polymer latex of the present invention”. To express. However, the “polymer latex” mentioned here is a water-insoluble hydrophobic polymer dispersed as fine particles in a water-soluble dispersion medium. As the dispersion state, the polymer is emulsified in a dispersion medium, the emulsion is polymerized, the micelle is dispersed, or the polymer molecule has a partially hydrophilic structure and the molecular chain itself is molecularly dispersed. Anything may be used. As for the polymer latex of the present invention, `` synthetic resin emulsion (Hiraku Okuda, Hiroshi Inagaki, published by Kobunshi Publishing (1978)) '', `` Application of synthetic latex (Takaaki Sugimura, Ikuo Kataoka, Junichi Suzuki, Keiji Kasahara, Published by Polymer Publishing Association (1993)), “chemistry of synthetic latex (written by Soichi Muroi, published by Polymer Publishing Association (1970))”, and the like. The average particle size of the dispersed particles is preferably 1 to 50000 nm, more preferably about 5 to 1000 nm. The particle size distribution of the dispersed particles is not particularly limited, and may have a wide particle size distribution or a monodispersed particle size distribution.
[0027]
The polymer latex of the present invention may be a so-called core / shell type latex other than a normal polymer latex having a uniform structure. In this case, it may be preferable to change the glass transition temperature between the core and the shell.
[0028]
The minimum film forming temperature (mFT) of the polymer latex of the present invention is preferably -30 to 90 ° C, more preferably about 0 to 70 ° C. A film-forming auxiliary may be added to control the minimum film-forming temperature. Film-forming aids, also called plasticizers, are organic compounds that lower the minimum film-forming temperature of polymer latex (usually organic solvents). )"It is described in.
[0029]
Examples of the polymer species used in the polymer latex of the present invention include acrylic resins, vinyl acetate resins, polyester resins, polyurethane resins, rubber resins, vinyl chloride resins, vinylidene chloride resins, polyolefin resins, and copolymers thereof. The polymer may be a linear polymer, a branched polymer, or a crosslinked polymer. The polymer may be a so-called homopolymer obtained by polymerizing a single monomer, or a copolymer obtained by polymerizing two or more monomers. In the case of a copolymer, it may be a random copolymer or a block copolymer. The molecular weight of the polymer is 5,000 to 100,000, preferably about 10,000 to 100,000 in terms of number average molecular weight. When the molecular weight is too small, the mechanical strength of the image forming layer is insufficient, and when the molecular weight is too large, the film forming property is poor, which is not preferable.
[0030]
The polymer latex polymer used in the present invention preferably has an equilibrium water content of 2 wt% or less, more preferably 1 wt% or less at 25 ° C. and 60% RH. For the definition and measurement method of the equilibrium moisture content, for example, “Polymer Engineering Course 14, Polymer Material Testing Method (Edited by Polymer Society, Jinshokan)” can be referred to.
[0031]
Specific examples of the polymer latex used as the binder for the image forming layer of the photothermographic material of the present invention include the following. Latex of methyl methacrylate / ethyl acrylate / methacrylic acid copolymer, latex of methyl methacrylate / 2 ethylhexyl acrylate / styrene / acrylic acid copolymer, latex of styrene / butadiene / acrylic acid copolymer, latex of styrene / butadiene / divinylbenzene / methacrylic acid copolymer, Methyl methacrylate / vinyl chloride / acrylic acid copolymer latex, vinylidene chloride / ethyl acrylate / acrylonitrile / methacrylic acid copolymer latex, and the like. Moreover, such a polymer is also marketed and the following polymers can be utilized. For example, as an example of an acrylic resin, Sebian A-4635,46583, 4601 (manufactured by Daicel Chemical Industries, Ltd.), Nipol Lx811, 814, 821, 820, 857 (manufactured by Nippon Zeon Co., Ltd.), etc. FINETEX ES650, 611, 675, 850 (Dainippon Ink Chemical Co., Ltd.), WD-size, WmS (Eastman Chemical), and other polyurethane resins are HYDRAN AP10, 20, 30, 40 (above Rubber resins such as LACSTAR 7310K, 3307B, 4700H, 7132C (above Dainippon Ink and Chemicals Co., Ltd.), Nipol Lx416, 410, 438C, 2507, Etc.), G351 and G576 (made by Nippon Zeon Co., Ltd.) for vinyl chloride resin, L502 and L513 (made by Asahi Kasei Kogyo Co., Ltd.) for vinylidene chloride resin, and Chemipearl S for olefin resin. -120, SA100 (Mitsui Petrochemical Co., Ltd.) wear. These polymers may be used alone or in combination of two or more as required.
[0032]
The organic silver salt-containing liquid or a thermal imaging layer coating solution of the present invention is more 50 wt% of the total binder Ri said polymer latex der, more preferably more than 70 wt% is the polymer latex.
[0033]
The organic silver salt-containing liquid or the thermal image forming layer coating liquid of the present invention has a hydrophilicity such as gelatin, polyvinyl alcohol, methylcellulose, hydroxypropylcellulose, carboxymethylcellulose, hydroxypropylmethylcellulose and the like within a range of less than 50 wt% of the total binder as necessary. A functional polymer may be added. The amount of these hydrophilic polymers added is preferably 30 wt% or less of the total binder in the image forming layer.
[0034]
The organic silver salt-containing liquid or thermal image forming layer coating liquid of the present invention is aqueous . Here, “aqueous” means that 30 wt% or more of the solvent (dispersion medium) of the coating solution is water. As components other than water in the coating solution, water-miscible organic solvents such as methyl alcohol, ethyl alcohol, isopropyl alcohol, methyl cellosolve, ethyl cellosolve, dimethylformamide, and ethyl acetate can be used. Specific examples of the solvent composition include the following. Water / methanol = 90/10, water / methanol = 70/30, water / ethanol = 90/10, water / isopropanol = 90/10, water / dimethylformamide = 95/5, water / methanol / dimethylformamide = 80 / 15/5, water / methanol / dimethylformamide = 90/5/5. (However, the numbers represent wt%.)
[0035]
The total binder amount in the image forming layer of the present invention is preferably 0.2 to 30 g / m ² , more preferably 1 to 15 g / m ² . The image forming layer of the present invention may contain a crosslinking agent for crosslinking, a surfactant for improving coating properties, and the like.
[0036]
The method for forming photosensitive silver halide in the present invention is well known in the art, and for example, the methods described in Research Disclosure No. 17029 of June 1978 and US Pat. No. 3,700,458 can be used. . Specific methods that can be used in the present invention include a method in which a part of silver of an organic silver salt is converted into photosensitive silver halide by adding a halogen-containing compound to the prepared organic silver salt, gelatin Alternatively, a method of preparing photosensitive silver halide grains by adding a silver supply compound and a halogen supply compound to another polymer solution and mixing it with an organic silver salt can be used. In the present invention, the latter method can be preferably used. The grain size of the photosensitive silver halide is preferably small for the purpose of keeping white turbidity after image formation low, specifically 0.20 μm or less, more preferably 0.01 μm or more and 0.15 μm or less, more preferably 0.02 μm or more. 0.12 μm or less is preferable. The grain size here means the length of the edge of the silver halide grain when the silver halide grain is a so-called normal crystal of a cube or octahedron. Further, when the silver halide grain is a tabular grain, it means a diameter when converted into a circular image having the same area as the projected area of the main surface. In the case of other non-normal crystals, for example, in the case of spherical grains, rod-shaped grains, etc., it means the diameter when considering a sphere equivalent to the volume of silver halide grains.
[0037]
Examples of the shape of the silver halide grains include cubes, octahedrons, tabular grains, spherical grains, rod-shaped grains, and potato grains. In the present invention, cubic grains and tabular grains are particularly preferred. When tabular silver halide grains are used, the average aspect ratio is preferably 100: 1 to 2: 1, more preferably 50: 1 to 3: 1. Further, grains having rounded corners of silver halide grains can be preferably used. There are no particular restrictions on the surface index (Miller index) of the outer surface of the photosensitive silver halide grains, but the {100} surface occupies a high proportion of spectral sensitization efficiency when the spectral sensitizing dye is adsorbed. preferable. The ratio is preferably 50% or more, more preferably 65% or more, and still more preferably 80% or more. The ratio of Miller index {100} plane is calculated by T.Tani; J.Imaging Sci., 29, 165 (1985) using the adsorption dependence of {111} plane and {100} plane in sensitizing dye adsorption. It can be determined by the method described. The halogen composition of the photosensitive silver halide is not particularly limited and may be any of silver chloride, silver chlorobromide, silver bromide, silver iodobromide, silver iodochlorobromide, and silver iodide. In the present invention, silver bromide or silver iodobromide can be preferably used. Particularly preferred is silver iodobromide, and the silver iodide content is preferably from 0.1 mol% to 40 mol%, more preferably from 0.1 mol% to 20 mol%. The distribution of the halogen composition in the grain may be uniform, the halogen composition may be changed stepwise, or may be continuously changed. High silver iodobromide grains can be used. In addition, silver halide grains preferably having a core / shell structure can be used. As the structure, core / shell particles having a preferably 2- to 5-fold structure, more preferably a 2- to 4-fold structure can be used.
[0038]
The photosensitive silver halide grain of the present invention preferably contains at least one metal complex selected from rhodium, rhenium, ruthenium, osnium, iridium, cobalt, mercury or iron. One kind of these metal complexes may be used, or two or more kinds of complexes of the same metal and different metals may be used in combination. The preferred content is in the range of 1 nmol to 10 mmol, and more preferably in the range of 10 nmol to 100 μmol, with respect to 1 mol of silver. As a specific metal complex structure, a metal complex having a structure described in JP-A-7-225449 can be used. For cobalt and iron compounds, hexacyano metal complexes can be preferably used. Specific examples include, but are not limited to, ferricyanate ions, ferrocyanate ions, hexacyanocobaltate ions, and the like. The phase containing the metal complex in the silver halide may be uniform, may be contained in the core part at a high concentration, or may be contained in the shell part at a high concentration, and is not particularly limited.
[0039]
The photosensitive silver halide grains can be desalted by washing with water known in the art, such as a noodle method or a flocculation method, but in the present invention, it may or may not be desalted.
[0040]
The photosensitive silver halide grains in the present invention are preferably chemically sensitized. As a preferable chemical sensitization method, a sulfur sensitization method, a selenium sensitization method and a tellurium sensitization method can be used as is well known in the art. Further, noble metal sensitization methods such as gold compounds, platinum, palladium, iridium compounds and reduction sensitization methods can be used. As the compound preferably used in the sulfur sensitization method, selenium sensitization method and tellurium sensitization method, known compounds can be used, but compounds described in JP-A-7-128768 and the like can be used. Examples of tellurium sensitizers include diacyl tellurides, bis (oxycarbonyl) tellurides, bis (carbamoyl) tellurides, diacyl tellurides, bis (oxycarbonyl) ditellurides, bis (carbamoyl) ditellurides, P = Te Compounds having a bond, tellurocarboxylates, Te-organyl tellurocarboxylates, di (poly) tellurides, tellurides, tellurols, telluroacetals, tellurosulfonates, compounds having a P-Te bond, Te heterocycles, tellurocarbonyl compounds, inorganic tellurium compounds, colloidal tellurium and the like can be used. As the compound preferably used for the noble metal sensitization method, for example, chloroauric acid, potassium chloroaurate, potassium aurithiocyanate, gold sulfide, gold selenide, or compounds described in US Pat. No. 2,448,060, British Patent 618,061, etc. are preferable. Can be used. As specific compounds of the reduction sensitization method, for example, stannous chloride, aminoiminomethanesulfinic acid, hydrazine derivatives, borane compounds, silane compounds, polyamine compounds, etc. can be used in addition to ascorbic acid and thiourea dioxide. . Further, reduction sensitization can be performed by ripening the emulsion while maintaining the pH at 7 or higher or pAg at 8.3 or lower. Further, reduction sensitization can be performed by introducing a single addition portion of silver ions during grain formation.
[0041]
The amount of the photosensitive silver halide of the present invention is preferably 0.01 to 0.5 mol, more preferably 0.02 to 0.3 mol, more preferably 0.03 to 0.25 mol, per mol of the organic silver salt. The following are particularly preferred: Regarding the mixing method and mixing conditions of photosensitive silver halide and organic silver salt prepared separately, the silver halide particles and organic silver salt prepared respectively are mixed with a high-speed stirrer, ball mill, sand mill, colloid mill, vibration mill, homogenizer, etc. Or a method of preparing an organic silver salt by mixing photosensitive silver halide that has been prepared at any timing during the preparation of the organic silver salt. There is no particular limitation as long as it appears.
[0042]
As the silver halide preparation method of the present invention, a so-called hydration method in which a part of silver of the organic silver salt is halogenated with an organic or inorganic halide is also preferably used. Any organic halide may be used as long as it is a compound that reacts with an organic silver salt to produce silver halide. However, N-halogenoimide (N-bromosuccinimide, etc.), halogenated quaternary nitrogen compound (odor) And tetrabutylammonium bromide), and halogenated quaternary nitrogen salts and halogen molecule associations (pyridinium perbromide). The inorganic halogen compound may be any compound as long as it is a compound that reacts with an organic silver salt to produce silver halide, but alkali metal halide or ammonium (sodium chloride, lithium bromide, potassium iodide, ammonium bromide, etc. ), Alkaline earth metal halides (calcium bromide, magnesium chloride, etc.), transition metal halides (ferric chloride, cupric bromide, etc.), metal complexes with halogen ligands (sodium iridate bromide) , Ammonium rhodate, etc.) and halogen molecules (bromine, chlorine, iodine). Moreover, you may use desired organic inorganic halide together.
[0043]
In the present invention, the amount of halide added during the halide is preferably 1 to 500 mmol, more preferably 10 to 250 mmol, as a halogen atom per mol of the organic silver salt.
[0044]
The photosensitive silver halide in the present invention may be spectrally sensitized with a sensitizing dye.
[0045]
Any sensitizing dye of the present invention may be used as long as it can spectrally sensitize the silver halide grains in a desired wavelength region when adsorbed on the silver halide grains. As the sensitizing dye, a cyanine dye, a merocyanine dye, a complex cyanine dye, a complex merocyanine dye, a hoholor cyanine dye, a styryl dye, a hemicyanine dye, an oxonol dye, a hemioxonol dye, or the like can be used. Useful sensitizing dyes used in the present invention are described in, for example, the references described or cited in RESEARCH DISCLOSURE Item 17643IV-A (December 1978 p.23), Item1831X (August 1979 p.437) Has been. In particular, a sensitizing dye having a spectral sensitivity suitable for the spectral characteristics of the light sources of various laser imagers, scanners, image setters and plate-making cameras can be advantageously selected.
[0046]
As an example of spectral sensitization to red light, a so-called red light source such as a He-Ne laser, a red semiconductor laser, or an LED is disclosed in I-1 to I-38 described in JP-A-54-18726. Compounds, compounds of I-1 to I-35 described in JP-A-6-75322, compounds of I-1 to I-34 described in JP-A-7-287338, and dyes described in JP-B-55-39818 From 1 to 20, compounds of I-1 to I-37 described in JP-A-62-284343 and compounds of I-1 to I-34 described in JP-A-7-287338 are advantageously selected.
[0047]
For semiconductor laser light sources in the wavelength region of 750-1400 nm, it can be spectrally sensitized with various known dyes including cyanine, merocyanine, styryl, hemicyanine, oxonol, hemioxonol and xanthene dyes. it can. Useful cyanine dyes are, for example, cyanine dyes having basic nuclei such as thiazoline nucleus, oxazoline nucleus, pyrroline nucleus, pyridine nucleus, oxazole nucleus, thiazole nucleus, selenazole nucleus and imidazole nucleus. Useful merocyanine dyes are preferably acidic nuclei such as thiohydantoin nucleus, rhodanine nucleus, oxazolidinedione nucleus, thiazolinedione nucleus, barbituric acid nucleus, thiazolinone nucleus, malononitrile nucleus and pyrazolone nucleus in addition to the above basic nucleus. Including. Of the above-mentioned cyanine and merocyanine dyes, those having an imino group or a carboxyl group are particularly effective. For example, U.S. Pat.Nos. -194781 and 6-301141 may be appropriately selected from known dyes.
[0048]
Particularly preferred as the structure of the dye used in the present invention is a cyanine dye having a thioether bond-containing substituent (for example, JP-A Nos. 62-58239, 3-138638, 3-138642, and 4- No. 255840, No. 5-72659, No. 5-72661, No. 6-222491, No. 2-230506, No. 6-258757, No. 6-317868, No. 6-324425, and No. 7- 500926, a dye described in U.S. Pat.No. 5,541,054), a dye having a carboxylic acid group (for example, dyes described in JP-A-3-163440, 6-301141, U.S. Pat.No. 5,441,899), a merocyanine dye, Multinuclear merocyanine dyes and polynuclear cyanine dyes (JP-A-47-6329, 49-105524, 51-127719, 52-80829, 54-61517, 59-214846, 60-6750) No. 63-159841, JP-A-6-35109, JP-A-6-59381, JP7-65537, JP7-65537, JP-T55-50111, British Patent 1,467,638, US Patent 5,281,515 Dyes described in 1).
[0049]
Further, as dyes forming J-band, U.S. Pat.Nos. 5,510,236 and 3,871,887 described in Example 5, JP-A-2-96131 and JP-A-59-48753 are disclosed, which are preferable in the present invention. Can be used.
[0050]
These sensitizing dyes may be used alone or in combination of two or more. A combination of sensitizing dyes is often used for the purpose of supersensitization. Along with the sensitizing dye, the emulsion itself may contain a dye having no spectral sensitizing action or a substance that does not substantially absorb visible light and exhibits supersensitization. Useful sensitizing dyes, combinations of dyes exhibiting supersensitization, and substances exhibiting supersensitization are described in Research Disclosure Vol. No. 43-4933, JP-A-59-19032, 59-192242 and the like.
[0051]
Two or more sensitizing dyes used in the present invention may be used in combination. In order to add sensitizing dyes to silver halide emulsions, they can be dispersed directly in the emulsion, or water, methanol, ethanol, propanol, acetone, methyl cellosolve, 2,2,3,3 -Solvent alone such as tetrafluoropropanol, 2,2,2-trifluoroethanol, 3-methoxy-1-propanol, 3-methoxy-1-butanol, 1-methoxy-2-propanol, N, N-dimethylformamide Alternatively, it may be dissolved in a mixed solvent and added to the emulsion.
[0052]
Further, as disclosed in US Pat. No. 3,469,987, etc., the dye is dissolved in a volatile organic solvent, the solution is dispersed in water or a hydrophilic colloid, and this dispersion is added to the emulsion. As disclosed in Japanese Patent Publication Nos. 44-23389, 44-27555, 57-22091, etc., the dye is dissolved in an acid and the solution is added to the emulsion, or the acid or base is added. Add to emulsion as aqueous solution by coexistence, and add aqueous solution or colloidal dispersion in the presence of surfactant as disclosed in US Pat. Nos. 3,822,135, 4,006,025, etc. As disclosed in JP-A-53-102733 and JP-A-58-105141, a method in which a dye is directly dispersed in a hydrophilic colloid, and the dispersion is added to an emulsion. As disclosed in US Pat. Construed, it is also possible to use a method of adding the solution to the emulsion. In addition, ultrasonic waves can be used for the solution.
[0053]
The time when the sensitizing dye used in the present invention is added to the silver halide emulsion of the present invention may be during any step of emulsion preparation that has been found useful. For example, as disclosed in the specifications of U.S. Pat. Or / and the time before desalting, during the desilvering step and / or after desalting to before the start of chemical ripening, as disclosed in the specification of JP-A-58-113920, etc. The emulsion may be added at any time just before or during the process, after chemical ripening and before the emulsion is coated before the coating. Further, as disclosed in the specifications of US Pat. No. 4,225,666 and Japanese Patent Application Laid-Open No. 58-7629, the same compound can be used alone or in combination with a compound of a different structure, for example, during the particle formation process. It may be added separately during the ripening process or after chemical ripening, divided before or during chemical ripening, or after completion of the process, etc. You may change and add.
[0054]
The amount of the sensitizing dye used in the present invention may be a desired amount in accordance with the performance such as sensitivity and fog, but is preferably 10 ⁻⁶ to 1 mol, preferably 10 ⁻⁴ to 1 mol per mol of silver halide in the photosensitive layer. 10 ^-1 mol is more preferred.
[0055]
Inclusion of an additive known as a “toning agent” that improves the image may increase the optical density. The toning agent may also be advantageous in forming a black silver image. The toning agent is preferably contained in the surface having the image forming layer in an amount of 0.1 to 50 mol%, more preferably 0.5 to 20 mol% per 1 mol of silver. The toning agent may be a so-called precursor that is derivatized so as to have an effective function only during development.
[0056]
In photothermographic materials using organic silver salts, a wide range of color toning agents are disclosed in JP-A-46-6077, 47-10282, 49-5019, 49-5020, 49-91215, 49-91215, 50-2524, 50-32927, 50-67132, 50-67641, 50-114217, 51-3223, 51-27923, 52- 14788, 52-99813, 53-1020, 53-76020, 54-156524, 54-156525, 61-183642, JP 4-56848, JP-B 49- No. 10727, No. 54-20333, US Pat. Nos. 3,080,254, 3,446,648, 3,782,941, 4,123,282, 4,510,236, British Patent 1380795, Belgian Patent 841910 and the like. Examples of toning agents are phthalimide and N-hydroxyphthalimide; succinimide, pyrazolin-5-one, and quinazolinone, 3-phenyl-2-pyrazolin-5-one, 1-phenylurazole, quinazoline and 2,4-thiazolidinedione Cyclic imides such as: naphthalimide (eg, N-hydroxy-1,8-naphthalimide); cobalt complex (eg, cobalt hexamine trifluoroacetate); 3-mercapto-1,2,4-triazole, 2,4 Mercaptans, exemplified by 2-dimercaptopyrimidine, 3-mercapto-4,5-diphenyl-1,2,4-triazole and 2,5-dimercapto-1,3,4-thiadiazole; N- (aminomethyl) aryl Dicarboximide (eg, (N, N-dimethylaminomethyl) phthalimide and N, N- (dimethylaminomethyl) -naphthalene-2,3-dicarboximide); Pyrazoles, isothiuronium derivatives and certain photobleaching agents (e.g., N, N-hexamethylenebis (1-carbamoyl-3,5-dimethylpyrazole), 1,8- (3,6-diazaoctane) bis (isothione) Uronium trifluoroacetate) and 2-tribromomethylsulfonyl)-(benzothiazole)); and 3-ethyl-5 [(3-ethyl-2-benzothiazolinylidene) -1-methylethylidene] -2- Thio-2,4-oxazolidinedione; phthalazinone, phthalazinone derivatives or metal salts, or 4- (1-naphthyl) phthalazinone, 6-chlorophthalazinone, 5,7-dimethoxyphthalazinone and 2,3-dihydro-1, Derivatives such as 4-phthalazinedione; combinations of phthalazinone and phthalic acid derivatives (eg, phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride); phthalazine, phthalates Gin derivatives or metal salts or derivatives such as 4- (1-naphthyl) phthalazine, 6-chlorophthalazine, 5,7-dimethoxyphthalazine and 2,3-dihydrophthalazine; phthalazine and phthalic acid derivatives (eg phthalates) Acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride, etc.); quinazolinedione, benzoxazine or naphthoxazine derivatives; for in situ silver halide generation as well as color modifiers Rhodium complexes that also function as a source of halide ions, such as ammonium hexachlororhodium (III), rhodium bromide, rhodium nitrate and potassium hexachlororhodium (III); inorganic peroxides and persulfates, such as diperoxide Ammonium sulfide and hydrogen peroxide; 1,3-benzoxazine-2,4-dione, 8-methyl Benzoxazine-2,4-diones such as 1,3-benzoxazine-2,4-dione and 6-nitro-1,3-benzoxazine-2,4-dione; pyrimidines and asymmetric-triazines (eg 2,4-dihydroxypyrimidine, 2-hydroxy-4-aminopyrimidine, etc.), azauracil, and tetraazapentalene derivatives (e.g., 3,6-dimercapto-1,4-diphenyl-1H, 4H-2,3a, 5 , 6a-tetraazapentalene, and 1,4-di (o-chlorophenyl) -3,6-dimercapto-1H, 4H-2,3a, 5,6a-tetraazapentalene).
[0057]
The toning agent of the present invention may be added by any method such as a solution, a powder, or a solid fine particle dispersion. The solid fine particle dispersion is performed by a known finer means (for example, ball mill, vibrating ball mill, sand mill, colloid mill, jet mill, roller mill, etc.). A dispersion aid may be used when dispersing the solid fine particles.
[0058]
The silver halide emulsions and / or organic silver salts in the present invention are further protected against the formation of additional fog by antifoggants, stabilizers and stabilizer precursors, and against reduced sensitivity during inventory storage. Can be stabilized. Suitable antifoggants, stabilizers and stabilizer precursors that can be used alone or in combination are the thiazonium salts described in U.S. Patent Nos. 2,131,038 and 2,694,716, U.S. Patent Nos. 2,886,437 and 2,444,605. Azaindene described in U.S. Pat.No. 2,728,663, mercury salt described in U.S. Pat.No. 3,287,135, sulfocatechol described in U.S. Pat. Indazole, polyvalent metal salts described in U.S. Pat.No. 2,839,405, thiuonium salts described in U.S. Pat. Halogen-substituted organic compounds described in US Pat. Nos. 4,108,665 and 4,442,202, U.S. Pat.Nos. 4,128,557 and 4,137,079, 4,138,365 and And triazine described in U.S. Pat. No. 4,459,350, and phosphorus compounds described in U.S. Pat. No. 4,411,985.
[0059]
Antifoggants preferably used in the present invention are organic halides, such as JP-A-50-119624, 50-120328, 51-121332, 54-58022, 56-70543, 56-99335, 59-90842, 61-129642, 62-129845, JP-A-6-208191, 7-5621, 7-2781, 8-15809, US Examples thereof include compounds disclosed in Japanese Patent Nos. 5340712, 5369000, and 5464737.
[0060]
The antifoggant of the present invention may be added by any method such as a solution, powder or solid fine particle dispersion. The solid fine particle dispersion is performed by a known finer means (for example, ball mill, vibrating ball mill, sand mill, colloid mill, jet mill, roller mill, etc.). A dispersion aid may be used when dispersing the solid fine particles.
[0061]
Although not necessary to practice the present invention, it may be advantageous to add mercury (II) salts to the emulsion layers as antifoggants. Preferred mercury (II) salts for this purpose are mercury acetate and mercury bromide. The amount of mercury used in the present invention is preferably in the range of 1 nmol to 1 mmol, more preferably 10 nmol to 100 μmol, per mol of applied silver.
[0062]
The photothermographic material in the invention may contain benzoic acids for the purpose of increasing sensitivity and preventing fog. The benzoic acid of the present invention may be any benzoic acid derivative. Examples of preferred structures include U.S. Pat. Nos. 4,784,939, 4,152,160, Japanese Patent Application Nos. 8-151422, 8-151411, and 8-98051. And the compounds described in. The benzoic acids of the present invention may be added to any part of the light-sensitive material, but the addition layer is preferably added to the layer having the photosensitive layer, and more preferably added to the organic silver salt-containing layer. . The benzoic acid of the present invention may be added at any step of preparing the coating solution, and when added to the organic silver salt-containing layer, any step from the preparation of the organic silver salt to the preparation of the coating solution may be used. It is preferable that the salt is prepared and immediately before coating. As a method for adding the benzoic acid of the present invention, any method such as powder, solution, fine particle dispersion and the like may be used. Moreover, you may add as a solution mixed with other additives, such as a sensitizing dye, a reducing agent, and a color toning agent. The addition amount of the benzoic acid of the present invention may be any amount, but it is preferably 1 μmol or more and 2 mol or less, more preferably 1 mmol or more and 0.5 mol or less per 1 mol of silver.
[0063]
In the present invention, a mercapto compound, a disulfide compound, and a thione compound can be contained in order to suppress or promote development and control development, to improve spectral sensitization efficiency, and to improve storage stability before and after development. .
[0064]
When a mercapto compound is used in the present invention, it may have any structure, but those represented by Ar-Sm and Ar-SS-Ar are preferred. In the formula, m is a hydrogen atom or an alkali metal atom, and Ar is an aromatic ring or condensed aromatic ring having one or more nitrogen, sulfur, oxygen, selenium or tellurium atoms. Preferably, the heteroaromatic ring is benzimidazole, naphthimidazole, benzothiazole, naphthothiazole, benzoxazole, naphthoxazole, benzoselenazole, benzotelrazole, imidazole, oxazole, pyrazole, triazole, thiadiazole, tetrazole, triazine, pyrimidine, pyridazine , Pyrazine, pyridine, purine, quinoline or quinazolinone. The heteroaromatic ring can be, for example, halogen (e.g., Br and Cl), hydroxy, amino, carboxy, alkyl (e.g., having one or more carbon atoms, preferably 1 to 4 carbon atoms) and alkoxy ( For example, it may have one selected from a substituent group consisting of one or more carbon atoms, preferably one having 1 to 4 carbon atoms. Mercapto-substituted heteroaromatic compounds include 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, 2-mercapto-5-methylbenzimidazole, 6-ethoxy-2-mercaptobenzothiazole, 2, 2'-dithiobis- (benzothiazole, 3-mercapto-1,2,4-triazole, 4,5-diphenyl-2-imidazolethiol, 2-mercaptoimidazole, 1-ethyl-2-mercaptobenzimidazole, 2-mercapto Quinoline, 8-mercaptopurine, 2-mercapto-4 (3H) -quinazolinone, 7-trifluoromethyl-4-quinolinethiol, 2,3,5,6-tetrachloro-4-pyridinethiol, 4-amino-6 -Hydroxy-2-mercaptopyrimidine monohydrate, 2-amino-5-mercapto-1,3,4-thiadiazole, 3-amino-5-mercapto-1,2,4-triazole, 4-hydrido Rosi-2-mercaptopyrimidine, 2-mercaptopyrimidine, 4,6-diamino-2-mercaptopyrimidine, 2-mercapto-4-methylpyrimidine hydrochloride, 3-mercapto-5-phenyl-1,2,4-triazole, Examples include 2-mercapto-4-phenyloxazole, but the present invention is not limited to these.
[0065]
The addition amount of these mercapto compounds is preferably in the range of 0.001 to 1.0 mol per mol of silver in the emulsion layer, and more preferably 0.01 to 0.3 mol per mol of silver.
[0066]
In the photosensitive layer in the present invention, a polyhydric alcohol (for example, glycerin and diol of the type described in US Pat. No. 2,960,404) as a plasticizer and a lubricant, described in US Pat. Nos. 2,588,765 and 3,121,060 are used. Fatty acids or esters, silicone resins described in British Patent No. 955,061 and the like can be used.
[0067]
In the present invention, an ultrahigh contrast agent can be used to form an ultrahigh contrast image. For example, U.S. Patent Nos. 5,464,738, 5,496,695, 6,512,411, 5,536,622, Japanese Patent Application Nos. 7-228627, 8-215822, 8-130842, 8-148113, 8 -156378, 8-148111, 8-148116, or a compound having a quaternary nitrogen atom described in Japanese Patent Application No. 8-83566 or U.S. Pat.No. 5,545,515 These acrylonitrile compounds can be used. Specific examples of the compound include compounds 1 to 10 of the above-mentioned U.S. Pat.No. 5,464,738, H-1 to H-28 of 5,496,695, I-1 to I-86 of Japanese Patent Application No. 8-215822, and 8- 130842 H-1 to H-62, 8-148113 1-1 to 1-21, 8-148111 1-50, 8-148116 1-40, 8-83566 P-1 to P-26 and T-1 to T-18, CN-1 to CN-13 of US Pat. No. 5,545,515, and the like.
[0068]
Further, in the present invention, in order to form a super high contrast image, a high contrast accelerator can be used in combination with the super high contrast agent. For example, amine compounds described in U.S. Pat.No. 5,545,505, specifically Am-1 to Am-5, hydroxamic acids described in 5,545,507, specifically HA-1 to HA-11, and 5,545,507 Described acrylonitriles, specifically CN-1 to CN-13, hydrazine compounds described in US Pat. No. 5,558,983, specifically CA-1 to CA-6, described in Japanese Patent Application No. 8-132836 Onum salts, specifically A-1 to A-42, B-1 to B-27, C-1 to C-14, and the like can be used.
[0069]
The synthesis method, the addition method, the addition amount, and the like of these super-high contrast agents and high-contrast accelerators can be performed as described in the respective cited patents.
[0070]
The image forming material in the present invention can be provided with a surface protective layer for the purpose of preventing adhesion of the image forming layer.
[0071]
The binder for the surface protective layer of the present invention may be any polymer, but preferably contains 100 mg / m ² or more and 5 g / m ² or less of a polymer having a carboxylic acid residue. Examples of the polymer having a carboxyl residue are natural polymers (gelatin, alginic acid, etc.), modified natural polymers (carboxymethylcellulose, phthalated gelatin, etc.), synthetic polymers (polymethacrylate, polyacrylate, polyalkylmethacrylate / acrylate). Copolymer, polystyrene / polymethacrylate copolymer, etc.). The carboxy residue content of the polymer is preferably 10 mmol or more and 1.4 mol or less per 100 g of the polymer. In addition, the carboxylic acid residue may form a salt with an alkali metal ion, an alkaline earth metal ion, an organic cation or the like.
[0072]
Any adhesion preventing material may be used as the surface protective layer of the present invention. Examples of anti-adhesive materials include wax, silica particles, styrene-containing elastomeric block copolymers (e.g., styrene-butadiene-styrene, styrene-isoprene-styrene), cellulose acetate, cellulose acetate butyrate, cellulose propionate, and these There is a mixture. In addition, a crosslinking agent for crosslinking, a surfactant for improving coating properties, and the like may be added to the surface protective layer.
[0073]
In the image forming layer or the protective layer of the image forming layer in the present invention, a light absorbing substance and a filter dye as described in U.S. Pat.Nos. 3,253,921, 2,274,782, 2,527,583 and 2,956,879 are used. Can be used in photographic elements including. For example, a dye can be mordanted as described in US Pat. No. 3,282,699. The amount of filter dye used is preferably an absorbance at an exposure wavelength of 0.1 to 3, particularly preferably 0.2 to 1.5.
[0074]
The image forming layer of the image forming layer or emulsion layer in the present invention contains a matting agent such as starch, titanium dioxide, zinc oxide, silica, and beads of the type described in US Pat. Nos. 2,992,101 and 2,701,245. Polymer beads and the like can be contained. The matte degree of the emulsion surface may be any as long as no stardust failure occurs, but the Beck smoothness is preferably 200 seconds or more and 10,000 seconds or less, and particularly preferably 300 seconds or more and 10,000 seconds or less.
[0075]
The heat-developable photographic emulsion of the present invention is composed of one or more layers on a support. One layer composition must contain organic silver salts, silver halides, developers and binders, and optional additional materials such as toning agents, coating aids and other aids. The two-layer construction must contain an organic silver salt and silver halide in the first emulsion layer (usually the layer adjacent to the substrate) and some other ingredients in the second or both layers. Don't be. However, a two-layer configuration comprising a single emulsion layer containing all components and a protective topcoat is also conceivable. The construction of a multicolor photosensitive photothermographic material may include a combination of these two layers for each color and includes all components in a single layer as described in US Pat. No. 4,708,928. Also good. In the case of multi-dye multi-color photothermographic materials, each emulsion layer generally uses a functional or non-functional barrier layer between each photosensitive layer as described in US Pat. No. 4,460,681. By doing so, they are kept distinguished from each other.
[0076]
Various dyes and pigments can be used for the photosensitive layer of the present invention from the viewpoint of improving the color tone and preventing irradiation. Any dyes and pigments may be used for the photosensitive layer of the present invention, for example, there are pigments and dyes described in the color index, specifically pyrazoloazole dyes, anthraquinone dyes, azo dyes, azomethine dyes, oxonol dyes, Examples thereof include carbocyanine dyes, styryl dyes, triphenylmethane dyes, indoaniline dyes, indophenol dyes, organic pigments such as phthalocyanine, and inorganic pigments. Preferred dyes used in the present invention include anthraquinone dyes (for example, compounds 1 to 9 described in JP-A-5-341441, compounds 3-6 to 18 and 3-23 to 38 described in JP-A-5-165147), azomethine Dyes (such as compounds 17 to 47 described in JP-A-5-341441), indoaniline dyes (for example, compounds 11 to 19 described in JP-A-5-289227, compounds 47 described in JP-A-5-341441, JP-A-5-341) And compounds 2-10 to 11 described in JP-A No. 165147) and azo dyes (compounds 10 to 16 described in JP-A-5-341441). As a method for adding these dyes, any method such as a solution, an emulsion, a solid fine particle dispersion, or a state mordanted in a polymer mordant may be used. The amount of these compounds to be used is determined by the target absorption amount, but generally it is preferably used in the range of 1 μg to 1 g per 1 m ² .
[0077]
In the present invention, the antihalation layer can be provided on the side far from the light source with respect to the photosensitive layer. The antihalation layer preferably has a maximum absorption in a desired wavelength range of 0.3 or more and 2 or less, more preferably an absorption of an exposure wavelength of 0.5 or more and 2 or less, and an absorption in the visible region after processing of 0.001 or more It is preferably less than 0.5, more preferably a layer having an optical density of 0.001 or more and less than 0.3.
[0078]
When an antihalation dye is used in the present invention, the dye has a desired absorption in the wavelength range, has a sufficiently small absorption in the visible region after the treatment, and can obtain any desired absorbance spectrum shape of the antihalation layer. It may be a compound. For example, the following is disclosed, but the present invention is not limited to this. As a single dye, JP-A-59-56458, JP-A-2-216140, JP-A-7-13295, JP-A-111432, U.S. Pat.No. 5,380,635, JP-A-2-68539, page 13, lower left column From line 1 to page 14, lower left column, line 9, line 3-24539, page 14, lower left column to page 16, lower right column, the compounds described in Japanese Patent Application Laid-Open No. 52-139136, 53-132334, 56-501480, 57-16060, 57-68831, 57-101835, 59-182436, JP-A-7-36145, 7 -199409, JP-B-48-33692, JP-B-50-16648, JP-B-2-41734, US Patents 4,088,497, 4,283,487, 4,548,896, and 5,187,049.
[0079]
The photothermographic material of the present invention is a so-called single-sided photosensitive material having a photosensitive layer containing at least one silver halide emulsion on one side of a support and a back layer on the other side. It is preferable.
[0080]
In the present invention, a matte agent may be added to the single-sided photosensitive material for improving the transportability. The matting agent is generally fine particles of an organic or inorganic compound that is insoluble in water. Any matting agent can be used.For example, the organic matting agents described in U.S. Pat.Nos. Those well known in the art such as the inorganic matting agents described in the respective specifications such as 1,260,772, 2,192,241, 3,257,206, 3,370,951, 3,523,022, and 3,769,020 can be used. For example, specific examples of organic compounds that can be used as matting agents include water-dispersible vinyl polymers such as polymethyl acrylate, polymethyl methacrylate, polyacrylonitrile, acrylonitrile-α-methylstyrene copolymer, polystyrene. , Styrene-divinylbenzene copolymer, polyvinyl acetate, polyethylene carbonate, polytetrafluoroethylene, etc. Examples of cellulose derivatives include methylcellulose, cellulose acetate, cellulose acetate propionate, etc. Examples of starch derivatives include carboxy starch, carboxynitrophenyl Preferably used for starch, urea-formaldehyde-starch reactants, gelatin hardened with known hardeners and hardened gelatin into cocapsulated hardened microcapsules Can be. As examples of the inorganic compound, silicon dioxide, titanium dioxide, magnesium dioxide, aluminum oxide, barium sulfate, calcium carbonate, silver chloride desensitized by a known method, silver bromide, glass, diatomaceous earth, and the like can be preferably used. . The above matting agents can be used by mixing different kinds of substances as required. There are no particular limitations on the size and shape of the matting agent, and those having an arbitrary particle size can be used. In the practice of the present invention, it is preferable to use one having a particle size of 0.1 μm to 30 μm. Further, the particle size distribution of the matting agent may be narrow or wide. On the other hand, since the matting agent greatly affects the haze and surface gloss of the light-sensitive material, the particle size, shape, and particle size distribution can be brought into a state as required by preparing the matting agent or mixing a plurality of matting agents. preferable.
[0081]
In the present invention, the matte degree of the back layer is preferably Beck smoothness of 250 seconds or less and 10 seconds or more, more preferably 180 seconds or less and 50 seconds or more.
[0082]
In the present invention, the matting agent is preferably contained in the outermost surface layer of the photosensitive material, the layer functioning as the outermost surface layer, or a layer close to the outer surface, and is contained in a layer acting as a so-called protective layer. It is preferable.
[0083]
In the present invention, a suitable binder for the back layer is transparent or translucent and generally colorless, and is a natural polymer synthetic resin, polymer and copolymer, and other media for forming a film such as gelatin, gum arabic, poly (vinyl alcohol), Hydroxyethyl cellulose, cellulose acetate, cellulose acetate butyrate, poly (vinyl pyrrolidone), casein, starch, poly (acrylic acid), poly (methyl methacrylic acid), poly (vinyl chloride), poly (methacrylic acid), copoly (styrene- Maleic anhydride), copoly (styrene-acrylonitrile), copoly (styrene-butadiene), poly (vinyl acetal) s (e.g., poly (vinyl formal) and poly (vinyl butyral)), poly (esters), poly (urethanes) ), Phenoxy resin, poly (vinylidene chloride), poly ( Pokishido), poly (carbonates), poly (vinyl acetate), cellulose esters, and polyamides. The binder may be coated from water or an organic solvent or emulsion.
[0084]
In the present invention, the back layer preferably has a maximum absorption of 0.3 or more and 2 or less in a desired wavelength range, more preferably 0.5 or more and 2 or less, and an absorption in the visible region after processing of 0.001 or more. It is preferably less than 0.5, more preferably a layer having an optical density of 0.001 or more and less than 0.3. Examples of the antihalation dye used for the back layer are the same as those of the antihalation layer described above.
[0085]
Backside resistive heating layers such as those shown in U.S. Pat. Nos. 4,460,681 and 4,374,921 can also be used in photosensitive photothermographic image systems.
[0086]
A hardener may be used for each layer such as the photosensitive layer, protective layer, and back layer of the present invention. Examples of hardeners include polyisocyanates described in US Pat. No. 4,281,060, JP-A-6-208193, epoxy compounds described in US Pat. No. 4,791,042, and JP-A 62-89048. The vinyl sulfone compounds described in the above are used.
[0087]
In the present invention, a surfactant may be used for the purpose of improving coating properties and charging. As an example of the surfactant, any nonionic, anionic, cationic, or fluorine-based one can be used as appropriate. Specifically, fluorine-based polymer surfactants described in JP-A-62-170950, US Pat. No. 5,380,644, etc., fluorine-based surfactants described in JP-A-60-244945, JP-A-63-188135, etc. Surfactants, polysiloxy acid surfactants described in U.S. Pat. No. 3,885,965, polyalkylene oxides and anionic surfactants described in JP-A-6-301140 and the like can be mentioned.
[0088]
Examples of the solvent used in the present invention include New Edition Solvent Pocket Book (Ohm, published in 1994), but the present invention is not limited thereto. The boiling point of the solvent used in the present invention is preferably 40 ° C. or higher and 180 ° C. or lower.
[0089]
Examples of the solvent of the present invention include hexane, cyclohexane, toluene, methanol, ethanol, isopropanol, acetone, methyl ethyl ketone, ethyl acetate, 1,1,1-trichloroethane, tetrahydrofuran, triethylamine, thiophene, trifluoroethanol, perfluoropentane, xylene. , N-butanol, phenol, methyl isobutyl ketone, cyclohexanone, butyl acetate, diethyl carbonate, chlorobenzene, dibutyl ether, anisole, ethylene glycol diethyl ether, N, N-dimethylformamide, morpholine, propane sultone, perfluorotributylamine, water, etc. Is mentioned.
[0090]
The photographic emulsion for heat development in the present invention can be coated on various supports. Typical supports are polyester film, primed polyester film, poly (ethylene terephthalate) film, polyethylene naphthalate film, cellulose nitrate film, cellulose ester film, poly (vinyl acetal) film, polycarbonate film and related or resinous Including materials, as well as glass, paper, metal and the like. Coated with flexible substrates, in particular partially acetylated or baryta and / or α-olefin polymers, in particular polymers of α-olefins having 2 to 10 carbon atoms such as polyethylene, polypropylene, ethylene-butene copolymers A coated paper support is typically used. The support may be transparent or opaque, but is preferably transparent.
[0091]
The light-sensitive material in the present invention is an antistatic or conductive layer, for example, a soluble salt (for example, chloride, nitrate, etc.), a vapor-deposited metal layer, an ionic polymer as described in US Pat. Nos. 2,861,056 and 3,206,312 or A layer containing an insoluble inorganic salt as described in US Pat. No. 3,428,451 may be included.
[0092]
As a method for obtaining a color image using the heat-developable photosensitive material in the present invention, there is a method described in JP-A-7-13295, page 10, left column, line 43 to 11, left column, line 40. Examples of color dye image stabilizers include British Patent 1,326,889, U.S. Patent 3,432,300, 3,698,909, 3,574,627, 3,573,050, 3,764,337, and 4,042,394. Yes.
[0093]
The photothermographic emulsion in the present invention can be coated by various coating operations including dip coating, air knife coating, flow coating or extrusion coating using a hopper of the type described in US Pat. No. 2,681,294. A preferable coating method of the present invention is a coating method described in pages 399 to 734 of LIQUID FILM COATING (CHAPMA & HALL, 1997) by Stephan F. Kistler and Peter M. Schweizer. Application is particularly preferred. Examples of the shape of the extrusion coater used for these coatings are described in Figures 11a.1 to 7 on pages 401 to 405 of the above-mentioned LIQUID FILM COATING, and the slide coater is described in FIG. 11b.1 on page 427 of the same book. The curtain coater is described in Fugue 11c.1-7 on pages 464-466 of the same book. If desired, two or more layers can be coated simultaneously by the methods described in US Pat. No. 2,761,791 and British Patent No. 837,095.
[0094]
Additional layers in the photothermographic material of the present invention, such as a dye-receiving layer for receiving a moving dye image, an opacifying layer when reflective printing is desired, a protective topcoat layer, and a primer known in the photothermographic art Layers can be included. The light-sensitive material of the present invention can preferably form an image with only one light-sensitive material, and it is preferable that a functional layer necessary for image formation such as an image receiving layer does not become another light-sensitive material.
[0095]
The photosensitive material of the present invention may be developed by any method, but is usually developed by raising the temperature of the photosensitive material exposed imagewise. The preferred development temperature is 80 to 250 ° C, more preferably 100 to 140 ° C. The development time is preferably 1 to 180 seconds, and more preferably 10 to 90 seconds.
[0096]
The light-sensitive material of the present invention may be exposed by any method, but laser light is preferred as the exposure light source. As the laser beam according to the present invention, a gas laser, a YAG laser, a dye laser, a semiconductor laser and the like are preferable. A semiconductor laser and a second harmonic generation element can also be used.
[0097]
The photosensitive material of the present invention has a low haze upon exposure and tends to generate interference fringes. As this interference fringe generation prevention technology, a laser beam disclosed in Japanese Patent Laid-Open No. 5-113548 is incident obliquely on the photosensitive material, or a multimode laser disclosed in WO95 / 31754 is used. Methods are known and these techniques are preferably used.
[0098]
In order to expose the photosensitive material of the present invention, SPIE vol.169 Laser Printing, pages 116-128 (1979), JP-A-4-51043, WO95 / 31754, etc. It is preferable to make the scanning line invisible.
[0099]
【Example】
Example 1 Organic Silver Salt-Containing Liquid << Preparation of Organic Silver Salt Dispersion >> 7 g of stearic acid, 4 g of arachidic acid, 36 g of behenic acid, and 187 ml of 1N-NaOH aqueous solution were added while stirring vigorously at 90 ° C. The reaction was allowed to proceed, and 65 ml of 1N nitric acid was added, and then the temperature was lowered to 50 ° C. Next, 125 ml of an aqueous solution of 21 g of silver nitrate was added over 100 seconds while stirring more vigorously, and left as it was for 20 minutes. Thereafter, the solid content was separated by suction filtration, and the solid content was washed with water until the filtrate had a conductivity of 30 μS / cm. To the solid content thus obtained, 100 g of a 10 wt% aqueous solution of hydroxypropylmethylcellulose was added, and water was further added to a total weight of 270 g, followed by elementary dispersion in an automatic mortar to obtain an organic silver salt-silver element dispersion. The organic silver salt-containing dispersion was dispersed at a pressure 1000 kg / cm ³ at the time of collision with a nanomizer (Nanomizer Co., Ltd.) to obtain an organic silver salt dispersion. The organic silver salt particles contained in the organic silver salt dispersion thus obtained were needle-like particles having an average minor axis of 0.04 μm, an average major axis of 0.8 μm, and a coefficient of variation of 30%.
[0100]
<< Preparation of reducing agent dispersion >>
To 100 g of 1,1-bis (2-hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane and 50 g of hydroxypropylcellulose, 850 g of water was added and mixed well to obtain a slurry. 840 g of zirconia beads having an average diameter of 0.5 mm were prepared, put into a vessel together with the slurry, and dispersed for 5 hours with a disperser (1/4 G sand grinder mill: manufactured by IMEX Co., Ltd.) to obtain a reducing agent dispersion.
[0101]
<< Preparation of Organic Silver Salt-Containing Liquid >> The amount of organic silver salt dispersion, reducing agent dispersion of Table 1 prepared as described above, Luck Star 3307B (Dainippon Ink Chemical Co., Ltd .; SBR Latex) An organic silver salt-containing liquid was prepared by mixing with a 10 wt% aqueous solution of polyvinyl alcohol (PVA: average polymerization degree 500, saponification degree 88%) and water so that the viscosity of Table 1 shows the results of measuring the viscosity of the organic silver salt-containing liquid thus obtained at 25 ° C. using an RFS fluid spectrometer manufactured by Rheometrics Far East Co., Ltd.
[0102]
<Applying and drying organic silver salt-containing liquid>
The coater of Fig. 1 was applied to a 175 μm polyethylene terephthalate support primed with Luck Star 3307B and gelatin, and the above-mentioned organic silver salt-containing liquid with a coating amount of 100 cc / m ² was applied at a coating speed of 100 m / min. The coated material was dried by applying a wind of 30% and 40% RH at a wind speed of 20 m / sec. In FIG. 1, the support 1 is continuously wound around the application backup roll 2. In applying the coating liquid 4 flowing out from the coating die 3 of the slide bead coating system onto the support 1, the coating liquid bead formed is stabilized by the decompression chamber 5. The support 1 to which the coating liquid 4 is applied is guided to the chilling zone A, and the coating liquid is cooled and stopped flowing, and then guided to the drying zone to volatilize the solvent in the coating liquid.
The surface shape of the resulting coated product was evaluated by the difference between the maximum and minimum silver amounts (g / m ² ) of the number of streaks and wind unevenness generated per 10 cm of coating width, as shown in Table 1. The results are shown in The smaller the value, the better the surface shape.
[0103]
It can be seen that a good surface shape is obtained in the region of the present invention.
[0104]
[Table 1]

[0105]
Example 2: Thermal imaging material << Preparation of silver halide grains >>
Dissolve 22 g of phthalated gelatin and 30 mg of potassium bromide in 700 ml of water, adjust the pH to 5.0 at a temperature of 35 ° C., and then add 159 ml of an aqueous solution containing 18.6 g of silver nitrate and 0.9 g of ammonium nitrate and 92 ml of potassium bromide and potassium iodide. An aqueous solution containing a molar ratio of: 8 was added over 10 minutes by the control double jet method while maintaining pAg of 7.7. Next, 476 ml of an aqueous solution containing 55.4 g of silver nitrate and 2 g of ammonium nitrate and an aqueous solution pAg7.7 containing 10 μmol / liter of dipotassium hexachloroiridate and 1 mol / liter of potassium bromide for 30 minutes by the control double jet method. After that, 1 g of 4-hydroxy-6-methyl-1,3,3a, 7-tetrazaindene was added, and the pH was further lowered to cause aggregation and sedimentation, followed by desalting. Thereafter, 0.1 g of phenoxyethanol was added to adjust the pH to 5.9 and pAg 8.2 to prepare silver iodobromide grains (iodine content core 8 mol%, average 2 mol%, average size 0.05 μm, projected area variation coefficient 8%, (100 ) Preparation of cubic particles) with an area ratio of 85%.
[0106]
The silver halide grains thus obtained were heated to 60 ° C. and 85 μmol of sodium thiosulfate and 11 μmol, 15 μmol of 2,3,4,5,6-pentafluorophenyldiphenylphosphine selenide per mol of silver. Tellurium compound, 3 μmol of chloroauric acid and 270 μmol of thiocyanic acid were added, and after aging for 120 minutes, rapidly cooled to 40 ° C., and then added with 100 μmol of dye and 500 μmol of 2-mercapto-5-methylbenzimidazole. A silver halide emulsion was obtained by rapid cooling to 0 ° C.
[0107]
<< Preparation of organic polyhalide dispersion >>
940 g of water was added to 50 g of tribromomethylphenylsulfone and 10 g of hydroxypropylcellulose, and mixed well to obtain a slurry. 840 g of zirconia beads having an average diameter of 0.5 mm were prepared, placed in a vessel together with the slurry, and dispersed for 5 hours with a disperser (1/4 G sand grinder mill: manufactured by IMEX Co., Ltd.) to obtain an organic polyhalide dispersion. .
[0108]
<< Preparation of emulsion layer coating solution >> 100 g of the organic silver salt dispersion obtained in Example 1, 20 g of the reducing agent dispersion, and 15 g of the above organic polyhalide dispersion, LUXSTAR 3307B (manufactured by Dainippon Ink & Chemicals, Inc.) ; SBR latex) 20 g, 10 g of the above silver halide emulsion, and water having the viscosity shown in Table 2 were mixed well to prepare an emulsion layer coating solution.
[0109]
<Preparation of emulsion surface protective layer coating solution>
270mg of sulfosuccinic acid di (2-ethylhexyl) ester sodium salt 860mg, polymethyl methacrylate fine particles (average particle size 2.5μm) 0.8g, phthalazine 5.3g, 4-methylphthalic acid 10g, aluminum sulfate 4.2g Then, water was added to 0.8 g of potassium chromium (III) sulfate dodecahydrate to give a total amount of 1600 cc to obtain a surface protective layer coating solution.
[0110]
<Back layer coating solution>
Solid base N, N, N, N-tetraethylguanidine and 4-carboxysulfonyl-phenylsulfone molar ratio 10g salt 10g polyvinyl alcohol 88g water 1 / 16G sand grinder mill (IMEX Co., Ltd.) To obtain a base solution.
[0111]
An organic solvent phase in which 2.1 g of basic dye precursor, 7.9 g of acidic substance, 0.1 g of dye and 10 g of ethyl acetate are mixed and dissolved is mixed in an aqueous phase consisting of 10 g of polyvinyl alcohol and 80 g of water, and emulsified and dispersed at room temperature. (Average particle size 2.5 μm) was obtained.
[0112]
The back surface coating solution was obtained by mixing 39 g of the base solution thus obtained, 26 g of the dye solution, and 36 g of a 10 wt% polyvinyl alcohol aqueous solution.
[0113]
<Back surface protective layer coating solution>
Gelatin 20g, polymethylmethacrylate (average particle size 7μm) 0.6g, sodium dodecylbenzenesulfonate 0.4g, X-22-2809 (Shin-Etsu Silicone Co., Ltd. silicone compound) 1g was dissolved in 480g of water and a back surface protective layer was applied. A liquid was obtained.
[0114]
<Preparation of thermal image forming material>
Lackster 3307B and 175 μm polyethylene terephthalate substrate primed with gelatin were coated with 50 g / m ² of the back layer protective layer coating solution at a flow rate of 647 nm optical density at 0.7, and then the back surface. After coating the emulsion layer coating solution on the opposite side of the coating so that the silver amount is 1.8 g / m ² and drying at 30 ° C. and 40% RH wind speed 20 m / sec, the emulsion surface protective layer coating solution is gelatin amount 2.2. was coated to a g / m ^2. The smoothness of the light-sensitive material thus obtained (the Beck smoothness was investigated using the Oken type smoothness measurement described in J. TAPPI paper pulp test method No. 5) was 1200 seconds for the emulsion surface and 85 seconds for the back surface. .
[0115]
[Chemical 1]

[0116]
(Surface evaluation)
The surface shape of the obtained coated product was evaluated by the difference between the maximum value and the minimum value (g / m ² ) of the silver amount of the coated product, and the number of streaks generated per coated width of 10 cm and the state of wind unevenness.
[0117]
(Evaluation of photographic performance)
After exposing the photographic material at an inclination of 30 degrees with respect to the normal line with a 647 nm Kr laser sensitometer (maximum output 500 mW), the photographic material was processed (developed) at 120 ° C for 15 seconds, and the resulting image was evaluated for density The total was done. The measurement results were evaluated by Dmin and sensitivity (the reciprocal of the ratio of the exposure amount giving a density 1.0 higher than Dmin). Regarding the sensitivity, the sensitivity of the photographic material 3 was set to 100.
[0118]
The results are shown in Table 2. It can be seen that both the surface shape and the photographic performance are good in the region of the present invention.
[0119]
[Table 2]

[0120]
Example 3
When N- (2-methoxyphenyl) -N-formylhydrazine was added to the emulsion layer coating solution of the photosensitive material 4 of Example 2 so that the coating amount was 1 mg / m ² , good surface condition and photographic performance were obtained. .
[0121]
Example 4
In the light-sensitive material 4 of Example 2, the silver halide in the emulsion layer coating solution was not added, but instead of the reducing agent dispersion, equimolar methyl 3,4-dihydroxybenzoate was added as an aqueous solution. A material to which neither a base solution nor a dye solution was added was used as a heat sensitive material. The heat-sensitive material thus obtained was heated at 90 ° C. for 5 seconds and the surface condition and color tone were evaluated.
[0122]
【The invention's effect】
According to the present invention, a thermal image forming material having a good surface shape and excellent image forming ability can be obtained.
[Brief description of the drawings]
FIG. 1 is a front view showing a part of a coater used in practical example 1 in a cutaway manner.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Support body 2 Application | coating backup roll 3 Coating die 4 Coating liquid 5 Decompression chamber A Chilling zone

Claims (7)

A liquid containing an organic silver salt and a binder , wherein 50 wt% or more of the binder is a polymer latex, and 30 wt% or more of the solvent of the liquid is water, and the viscosity at 25 ° C. is a shear rate of 0.1 500 mPa · s or more 500,000 mPa · s or less at S ^-1, and a method of applying a thermal imaging material to be applied is set lower than 0.1 mPa · s or higher 100 mPa · s at a shear rate 1000 S ^-1.  The method for applying a thermal image forming material according to claim 1, wherein the liquid further contains a reducing agent for silver ions.  The thermal image forming material coating method according to claim 1 or 2, wherein the organic silver salt is an organic carboxylic acid silver salt. Wherein the liquid further method of coating according to claim 1 to 3 either thermal imaging material containing a photosensitive silver halide. The organic silver salt, a binder and reducing agent for silver ion a including thermal imaging layer coating liquid, more 50 wt% of the binder is a polymer latex, or 30 wt% of the solvent of the thermal imaging layer coating solution is water, a viscosity at 25 ° C., and at 500 mPa · s or more 500,000 mPa · s or less at a shear rate of 0.1 s ^-1, and is 100 mPa · s and not more than 0.1 mPa · s at shear velocity of 1000S ^-1, the viscosity heat Image forming layer coating solution. The organic silver salt, a binder and reducing agent for silver ion a including thermal imaging layer coating liquid, more 50 wt% of the binder is a polymer latex, or 30 wt% of the solvent of the thermal imaging layer coating solution is water, thermal image a viscosity at 25 ° C. or less 500 mPa · s or more 500,000 mPa · s at a shear rate 0.1 s ^-1, and is 100 mPa · s and not more than 0.1 mPa · s at shear velocity of 1000S ^-1, the viscosity A thermal image forming material having a thermal image forming layer coated using a forming layer coating solution. The organic silver salt, a binder, a silver ion reducing agent and a photosensitive silver halide A including thermal imaging layer coating liquid, more 50 wt% of the binder is a polymer latex, said thermal image forming layer coating solution a 30 wt% or more of water solvent, and a viscosity at 25 ° C. or less 500 mPa · s or more 500,000 mPa · s at a shear rate 0.1 s ^-1, and 100 mPa · than 0.1 mPa · s at shear velocity of 1000S ^-1, the viscosity A photosensitive heat-developable image-forming material having a thermal image-forming layer coated with a thermal image-forming layer coating solution that is s or less.

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