DE2212302B2 - THERMOPHOTOGRAPHIC RECORDING MATERIAL - Google Patents

Description

OH

in which R _{3 is} a hydrogen atom or a methyl, ethyl, propyl, phenyl or 4-methylphenyl radical.

2. Thermo photographic Aufzeichnungsmate- rial according to claim 1, characterized in that Cs per mol of silver halide containing a total of 0.4 to 2.0 moles of reducing agent.

3. Thermophotographic recording material according to claim 1 and 2, characterized in that that it is bisnaphthol and 1,3-dihydroxybenzene derivative in a molar ratio of 10: 1 to 1: 5.

4. Thermophotographic recording material according to claim 1 to 3, characterized. that it contains 0.01 to 0.50 moles of light-sensitive silver halide per mole of oxidizing agent.

5. Thermophotographic recording material according to claim 1 to 4, characterized in that that it additionally contains a conventional stabilizer precursor compound.

6. Thermophotographic recording material according to claim 1 to 5, characterized in that that it also contains a conventional activator-toner compound.

7. Thermophotographic recording material according to claim 6, characterized in that it contains phthalimide or phthalazinone as an activator-toner compound.

60

The invention relates to a thermopholographic air / calibration maicrial, consisting of a slide and one or more chichia applied to it, in which light-sensitive silver halide and an image-forming combination of (a) an oxidizing agent consisting of the silver salt of an organic acid and ( b) a reducing agent consisting of a bisnaphthol are contained.

It is known e.g. B. from US-PS 31 52 903 and 31 52 904, Light-sensitive photographic recording materials in the dry way with feed of developing heat. Such recording materials contain, inter alia, a reducing agent, for example a l-phenyl-3-pyrazolidone Hydroxylamine compound, an aminophenoi, a diphenol, for example pyrocatechol or resorcinol, a aromatic ester, for example methyl gallate, or an aromatic diamine, for example phenylenediamine, an oxalate, formate or ascorbic acid.

It is also known, for example from US Pat. No. 3,094,619, to use thermophotographic recording materials which contain a reducing agent which is inactivated upon imagewise exposure to UV light for the production of photographic images by developing by dry means . In the thermal photographic recording material known from US Pat. No. 3,094,619, the reducing agent can consist, for example, of 1,1'-dihydroxy-2,2'-binaphthol. From US-PS 30 80 254 a thermophotographic recording material very similar to the thermophotographic recording material known from US-PS 30 94 619 is known, which as a reducing agent a λ- or ^ -naphthol together with 1- (2H) -phthalazinone as Contains toner.

Finally, it is further known, for example from US-PS 2165 421, to use 1,3-Dihydroxybenzolberbindungen together with aliphatic aldehydes in lichtempiindlichen photographic materials for hardening gelatin.

It has also been shown that the use of 1,3-dihydroxybenzene compounds, for example 2,4-dihydroxybenzaldehyde, the only one

Reducing agents in an image-forming system comprising an oxidizing agent and a reducing agent in photosensitive materials which are produced by Exposure to heat developed no increase in relative sensitivity and / or maximum Density leads.

The object of the invention is to provide a thermophotographic recording material which, according to the imagewise exposure by the action of heat can develop in the usual known manner, the however, compared to the previously known thermal photographic recording materials, images are higher maximum density with increased exposure latitude without increasing the minimum density.

The invention is based on the knowledge that the task set by the common use of a Bisnaphthol and a 1,3-dihydroxybenzene derivative of the structure shown below as reducing agents is solvable.

The subject of the invention is a thermophotographic Recording material, consisting of a layer support and one or more applied to it Layers in which or in which light-sensitive silver halide and an image-forming combination of (a) an oxidizing agent consisting of the silver salt of an organic acid and (b) one of a bisnaphthol existing reducing agent are included, which is characterized. that it is in at least one layer as the second reducing agent is a 1,3-dihydroxybenzene derivative of the following formula contains:

in which R _{3 is} a hydrogen atom or a methyl, ethyl, propyl, phenyl or 4-methylphenyl radical.

For the production of the thermophotographic recording materials 1,3-Dihydroxybenzene derivatives suitable according to the invention are accordingly:

2,4-dihydroxybenzaldehyde,

2,4-dihydroxybenzophenone,

2,4-dihydroxyacetophenone,

2 ', 4'-dinydroxy-4-methylbenzophenone,

2,4-dihydroxypropiophenone and

2,4-dihydroxybutyrophenone.

Bisnaphthols, for example, can be used as bisnaphthols the following formula can be used:

HO

OH

(II)

in which: Ri and R2 each represent a hydrogen or halogen atom, an alkyl radical having 1 to 3 carbon atoms, an alkoxy radical having 1 to 2 carbon atoms or a nitro or amino radical and η = 0 or 1.

The bisnaphthol of the following formula has proven to be a particularly suitable bisnaphthol:

(III)

OH \

Other bis-j3-naphthols which are particularly suitable for the production of thermophotographic recording materials according to the invention are, for example:
6,6'-dibromo-2,2'-dihydroxy-1,1'-binaphthyl
6,6'-Dinitro-2,2'-dihydroxy-U'-binaphthyl
Bis (2-hydroxy-1-naphthyl) methane
6,6'-diethoxy-bis [2-hydroxy-1-naphthylmethane
6.6'-diamino-2,2'-dihydroxy-l.1'-binaphthyl and
b.b'- dimethoxy-2,2'-dihydroxy-1,1'-binaphthyl.
The water-insoluble silver salts of long-chain fatty acids which are particularly light-stable, for example silver behenate and also silver stearate, have proven to be particularly advantageous oxidizing agents. Silver oleate, silver laurate, silver hydroxystcarate, silver caprate. Silver myristate and silver palniilate.

Other suitable silver salts of carboxylic acids are silver benzoate,

Silver ^ '- n-octadecyloxydiphenyM-carboxylate,
Silver o-aminobenzoate, silver acetamidobenzoate.
Silver furoate, silver camphorate,
Silver p-phenyl benzoate, silver phenyl acetate,

Silver salicylate, silver butyrate, silver terephthalate,
Silver phthalate, silver acetate and
Silver hydrogen phthalate.

It is known that in the present photosensitive System, the silver salts of organic acids called silver behenate form the silver behenate behave completely equivalent. Therefore, in the following statements, especially in the examples, only from Silver behenate may be mentioned, although with the same effect instead of silver behenate also the specified ones other silver salts can be used.

The light-sensitive silver halide of the thermophotographic recording material! » according to the invention can consist of one of the conventional silver halide used for the production of thermophotographic recording materials, for example silver chloride, silver bromide, silver bromide iodide. Silver chlorobromide iodide or mixtures thereof.

The light-sensitive silver halide can be coarse-grained or fine-grained. As special Very fine-grain emulsions have proven advantageous for the production of the recording materials.

Those used for the preparation of the thermal photographic recording materials according to the invention light-sensitive silver halides can be prepared, sensitized, stabilized or otherwise treated.

For the production of the thermophotographic recording materials According to the invention, the oxidizing agents consisting of silver salts and the light-sensitive silver halides are used in usual concentrations. As functional it has have been found to use 0.005 to 0.50 moles of silver halide per mole of silver salt.

The combination of reducing agents can be used in various concentrations. It has proven particularly advantageous to use 0.4 to 2.0 moles of the reducing agent combination per mole of light-sensitive silver halide. According to a particularly advantageous embodiment of the invention, 0.01 to 0.50 moles of light-sensitive silver halide per mole of silver salt oxidizing agent and 0.42 to 2.0 moles of bisnaphthol per mole of oxidizing agent at a molar ratio of bisnaphthol to 1,3-dihydroxybenzene derivative of 10: 1 used up to 1: 5.
Apart from the reducing agent combination used according to the invention, the thermophotographic recording materials according to the invention can thus for example have a structure as is known from US Pat. No. 3,457,075 and 3,152,904 and from BE-PS 7 66 589.

ho If necessary, for the production of the; Ί.τηιο-photographic Recording materials of the invention other than the bisnaphthols described and 1,3-dihydroxybenzene derivatives also have others common known reducing agents are used,

('1 e.g. silver halide developer compounds. such as polyhydroxybenzenes, ζ. B. hydroquinones, phenylenediamines, aminophenols, ascorbic acids and ascorbic acid derivatives. Hydroxylamines. i-pyrazolidones, hydro

«Ytetronic acids and hydroxytetronimides, as well as from Reductonen existing developer connections.

If necessary, it can be advantageous to use the Schichlen the thermophotographic recording materials according to the invention have other conventional additives to incorporate, for example an activator-toner compound to achieve deep black or special neutral black images, as well as stabilizers and stabilizer precursor compounds. By the way, you can For the production of the thermophotographic recordings the usual known colloidal materials Binders and / or synthetic polymers as binders, the most varied of customary organic and inorganic hardeners, plasticizers, surface-active compounds, matting agents, optical Brighteners, light-absorbing substances and compounds that increase sensitivity are used will. Finally, the thermophotographic recording materials according to the invention also have customary antistatic or conductive layers.

Typical for the preparation of the thermal photographic recording materials according to the invention suitable activator-toner compounds are heterocyclic compounds with at least one nitrogen atom of the following structural formula:

N-.

O = C

where: R is a hydrogen atom or metal ion, τ. B. a potassium, sodium, lithium, silver, gold or mercury ion, or a hydroxyl group and Z the atoms required to complete a heterocyclic nucleus, in particular a 5- or 6-membered heterocyclic nucleus, for example in the form of a group of following formula

CCH ₂ CH ₂

or an alkylene group having three or four carbon atoms. The heterocyclic nucleus can optionally be substituted, for example by amino or Alkylamino radicals, e.g. B. methylamino or ethylamino radicals, or by hydroxyl or carbamyl radicals.

As particularly advantageous activator-toner compounds have cyclic imides of the following formula

K.

O = C

C = O

proven, in which mean: R 'a hydrogen atom or do Metal ion, for example a potassium, sodium, lithium, silver, gold or mercury ion, or a Hydroxyl radical and Z the atoms required to complete a cyclic imide, preferably an imide core formed from 5 or 6 carbon atoms, e.g. B. a phthalimide or succinimide core. The atoms of these cyclic imide nuclei can optionally also be substituted, in particular by amino or alkyl radicals, especially those having 1 to 5 carbon atoms, for example by Methyl, ethyl, propyl, butyl or pentyl radicals, or by aryl radicals, in particular with 6 to 20 carbon atoms, for example the phenyl or naphthyl series, for example by phenyl, tolyl or xylyl radicals.

Typical advantageous activator-toner compounds which can be used to produce a recording material can be used according to the invention, for example:

Phthalimide.

N-hydroxyphthdlimide,

N-potassium phthalimide,

N-silver phthalimide,

N-mercury pnthalimide,

Succinimide and / or

N-hydroxysucenimide.

Together with or instead of the described activator-toner compounds consisting of cyclic [miden] Other activator-toner compounds can also be used, for example heterocyclic ones organic Toni_rverbindungen with at least two heteroatoms ^ in the heterocyclic ring, of dener. at least one is a nitrogen atom. Such toner compounds are, for example, from US Pat 30 80 254 and 34 46 648 known and consist, for example, of phthalazmon, phthalic anhydride. 2-acetylphthalazinone and 2-phthalylphthalazinone.

The activator-toner compounds described can be used in conventionally known concentrations are, preferably in concentrations of 0.1 to 1.05 moles per mole of oxidizing agent.

It has also proven to be advantageous in the thermographic recording materials, an image stabilizer compound or, in particular, a compound, capable of producing an image stabilizer compound, d. H. a stabilizer precursor compound, to use. By using these compounds, there may be some post-development occurrence Copying out by exposure to room light or background discoloration avoided or at least be reduced. Typical suitable stabilizer precursor compounds are, for example Azole thioethers and blocked azole thione stabilizer precursor compounds, e.g. B .:

5-acetyl-4-methyl-2- (3-oxobutylthio) thiazole;

4-FuiOyl-3-methylthio-1,2,4-thiadiazol-5-thione;

6-acetyl-4-methyl-3- (3-oxobutyl) -

thiazolin-2-thione and

2,6-di-tert-butyI-4- (l-phenyl-5-tetrazolyl) -

thiophenol.

The stabilizers and stabilizer precursor compounds can be used in conventionally known concentrations are used, in particular in a concentration of 0.002 to 0.10 moles per mole of oxidizing agent.

Optionally, for the production of the thermophotographic recording materials according to Invention non-aqueous, polar, organic solvents, for example compounds with a

—C S -

-SO ₂ -GrUpPC

should be used, as these are often the maximum

Ability to increase the image density even further. Typical suitable such non-aqueous solvents are for example tetrahydrothiophene-1,1-dioxide, 4-hydroxybutanoic acid lactone and methylsulfinyl methane.

In order to increase the maximum element density, divalent metal salts, which the Have the property of enhancing the developed images, for example zinc acetate, Cadmium acetate and cupric acetate. Such compounds can, for example, in concentrations of 0.005 to 0.20 moles, especially 0.010 to 0.10 moles can be used per mole of oxidizing agent.

Optionally, the light-sensitive silver halide in the thermophotographic recording material can be used can also be generated “in situ”, for example by a method as described in US Pat. No. 3,457,075 is known. For example, a dilute solution of a halogen acid, for example a solution of hydrochloric acid, on the surface of a thin layer containing an organic silver salt, for example Silver behenate. contains, and is applied to a suitable shooting rack. be applied, whereupon the solvent is removed.

The light-sensitive silver halide can further on or on the oxidizing agent, for example Silver behenate or silver stearate. before applying the silver halide to the support be generated. Such a method is known, for example, from US Pat. No. 3,457,075. For example a halogen acid, e.g. 8. Hydrochloric acid or Hydrobronic acid. with an organic silver salt mixed in a suitable reaction medium, whereupon a halide salt which is more soluble than Jas organic silver salt to a suspension of the organic silver salt is added to form silver halide. Aqueous Response media or other solutions included in the Do not interfere with the reaction.

Especially before copying out by exposure to light stable recording materials can be obtained by using highly pure starting materials, especially those that are free from halides and sulfides. By using high purity Silver behenai, for example, can reduce the risk of copying the background areas of a recording material be greatly reduced according to the invention.

For the production of thermophotographic recording materials according to the invention, the conventionally known film supports can be used.

For the production of the thermophotographic recording materials According to the invention, the most varied of customary known spectral sensitizing dyes can be used. It has proven to be useful to use this in Concentrations of from about 50 mg to about 2 g per mole of photosensitive silver halide are to be used.

According to an advantageous embodiment of the invention, the oxidizing agent consists of the thermophotographic Recording material made of silver behenate and the reducing agent combination of 2.2'-dihydroxy

the end

2.4

2,4-dihydroxybenzophenone and / or 27
cetphenon.

Particularly advantageous thermophotographic recording materials according to the invention are characterized in that they contain:
al light sensitive silver halide,

b) silver behenate,

c) 2,2'-dihydroxy-l, r-binaphthyl,

d) 2,4-dihydroxybenzaldehyde, 2,4-dihydroxybenzophenone or 2 ', 4'-dihydroxyacetophenone,

e) phthalimide,

f) S-Acetyl ^ -benzyloxycarbonylthio ^ -methylthiazole and

g) 3-Carboxymethyl-5 - [(3-methyl-2 (3H) -thiazolinylidene) -isopropylidene] rhodanine.

After exposure, the thermopholographisehen recording materials, the latent images thus obtained can be used in a conventional manner by simply heating the recording material to temperatures of about 80 to about developed 25O ⁰ C.

Preferably, temperatures are used of approximately 120 to 180 ^r C for development. By increasing or decreasing the heating time, higher or lower temperatures can be used within the specified range. As a rule, imagewise exposed thermophotographic recording materials according to the invention can be developed within a few seconds, for example within 0.5 to about 60 seconds, in particular within 0.5 to 5 seconds.

The development can take place under normal pressure and humidity conditions, but can the development may also be carried out under pressure and humidity conditions which lie outside of normal atmospheric conditions. Preferably, however, be atmospheric Conditions applied.

The exposed recording materials can be heated in a conventional manner, for example by using conventional simple heating plates, by irons or heating rollers.

It can optionally be advantageous that silver halide of the recording material in one layer and the other components in other layers accommodate. For example, a thermophotographic recording material according to the invention also of a support, a layer with light-sensitive photographic silver halide and a layer with

a) the oxidizing agent.

b) the combination of reducing agents and

c) there is preferably an activator-toner connection.

The layers can also have other customary ones Supplements included.

In the production of the thermophotographic recording materials according to the invention can the active components of the layer or layers of the thermophotographic recording material are dispersed in customary known binders or are dissolved in a known manner using solvents. Typical, in advantageous Suitable binders are binders! based on polyvinyl butyral.

The following examples are intended to further illustrate the invention.

First, a photosensitive silver halide silver behenate dispersion was prepared. For this purpose, First grind the ingredients listed below in a ball mill for 72 hours:

ίο

Silver behenate 84.0 g Behenic acid 64.0 g Polyvinyl butyral 30.0 g Phthalimide 17.0 g Acetone-toluene mixture (Volume ratio 1: 1) 1000, On

After grinding, 150 ml of an I.Ogew.-ffcigen Lithium bromide solution in acetone added, before the mixture obtained again for 16 hours Ifcng was stirred. The light-sensitive silver halide-silver behenate dispersion thus obtained is referred to as dispersion I in the following.

2.0 ml of Dispersion I were then mixed with the following ingredients:

1.0 ml of an 0.1% by weight solution of 3-carboxymethyl-5- [3-methyl-2 (3H) -thiazolinylidene) isopropylidene-rhodanine as a sensitizing dye in acetone

2.0 ml of a 5.0 wt .-% solution of one of the in the Bisnaphthols in acetone listed in Table I below

0.5 ml of a 1% strength by weight solution of 5-acetyl-2-benzoyloxycarbonylthio-4-methylthiazole in acetone

Table I.

0.3 ml of a 5% by weight solution of one of the 1,3-dihydroxybenzene derivatives listed in Table 1 below in methanol or acetone and
1: 8.0 ml of an acetone-toluene mixture in the weight of ^s 1 ratio.

The photosensitive coatings obtained were then applied to conventional photographic paper supports in a thickness, measured naf3, of about

ίο 0.010 cm applied and dried. The received Recording materials were then printed for 1 second in a conventional contact copier with a Tungsten lamp through a step wedge with a density difference from step to step of 0.3 logs exposed. The exposed thermophotographic recording materials were then brought into contact the side opposite the photosensitive cables of the recording material heated with a metal heating block. The heating time was approximately 4 seconds at one heating block temperature from 145 C.

The D _nm - and D _mi - "- reflection thicknesses", as well as the number of visible steps of the step wedge were determined. The results obtained are in the

is compiled in the following table 1:

Se sh I- Bisnaphthol R: π 1,3-dihydroxy Reflection densities I. 1.40 Dmin Number of eggs sees •- benzene black available levels de: ■ let no. Ri H O R3 deep 0.02 Step keiis (Formula II. Sp.3) Br O (Formula 1, column 3] black yellow-brown 1 H -CHj O H black White 11th 2 Br H (1.28) 8th 3 -CHi H O H black beige 10 deep (0.37) 4th 11th NO: O Phenyl black yellow-brown q - (CH :); CHs t deep White 5 NO: Phenyl black
(1.54)
deep 8th 6th -CH: CH: CHi H O Phenyl black White 9 1.30 (0.14) Γ H NH; O CHi White 11th te NH: NH: 1 ethyl 0.02 10 9 NH: Propvl 10

Example 2

The procedure described in Example 1 was repeated except that
a) other combinations of bisnaphthols with

b) the thermal photographic recording materials obtained for 7 seconds with a a temperature of 135 ° C heated metal block were brought into contact.

1,3-Dihydroxybenzene derivatives were used ₅₅ The results obtained are summarized in the following and that also in Table 2:

Table 2 Coating bisnaphthol

rnabMc No. Ki Kj

(Formula II, column 3)

1,3-dihydroxy

(Formula I, column 3)

Reflection densities

Dmax Dmm

number of

Stages of the Step keiis

10 H H 1 H deep black White 11th 11th -OCHi -OCHi 0 H ran black White 10 12th H H 0 H 1.36 0.02 11th 13th H H 1 Phenyl deep black White 11th

continuation Bisnaphlhol
Ri
(Formula II. Col. 3) R: η 1,3-Dih> droxy-
benzene
Ri
(Formula I. Col. 3) Reflection seals not quite
pure white
White number of
visible
Stages of the
Steps Coating
uings-
mass no. -OCH ₂ CHi
H -OCH.'CHi
H 1
1 Phenyl-4-methyl
methyl deep black
deep black 9
11 14th
15th

. one of the reducing agents has been omitted. The crazy

Example 3 Individual cases of heating temperatures used unc

(Comparative _example ) the heating lines as well as those obtained here

The procedure described in Example 1 was 15 results are summarized in the following Table 3

repeated with the exception, however, that at least:

Table 3

Designation Bisnaphthol R2 H η 1,3-dihydroxy Heating Heating Reflection densities Dmm Number of sight lung (Formula 11, Col. 3) benzene duration temperature, possible levels of the mass no. Ri H H 0 R3 in sec. C. Dniax 0.02 Step wedge _ (Formula I. Col. 3) 0.02 16 H NH2 0 without 4th 145 0.21 0.02 8th 17th - H 4th 145 0.14 0.02 7th 18th NH? H 0 without 7th 135 0.59 0.02 9 19th H 7th 135 0.04 0.02 4th 20th H 0 without 7th 135 0.47 0.02 6th 21 H 15th 135 0.14 6th 22nd without 15th 135 1.24 8th

When the results of Examples 1 are compared, they show a wider exposure latitude, where ".- and 2 with the results of Comparative Example 3 35 broadening the exposure latitude as a result of the fact that the thermophotographic recordings are greater in number
tion materials according to the invention is a surprise recognizable.
seeing increase in maximum density and a

visible steps of the step wedge

Claims (1)

'f patent claims: 1. Thermophotographic recording material, consisting of a layer support and a or more layers applied thereon in which or in which light-sensitive silver halide and an image-forming combination of (a) one of the silver salt of an organic acid existing oxidizing agent and (b) one of a bisnaphthol existing reducing agent are included, characterized in that the recording material in at least one Layer contains a 1,3-dihydroxybenzene derivative of the following formula as the second reducing agent: 15th