DD213528B5 - Stabilization and fog prevention method for color photographic silver halide materials - Google Patents

Abstract

An anti-fogging agent for colour- photographic silver-halide materials comprises a combination of certain alkylhydroquinones and certain quaternary N-alkyl-arenethiazolium salts. It gives good fog reduction without substantially impairing sensitivity.

Description

OH

in the

n: Ibis 4,

R: identical or different, straight-chain or branched alkyl groups having a

Total carbon number for all R from 5 to 40, and from compounds of general formula II,

χ ^β

in the

2: atomic grouping to complete an optionally substituted aromatic system,

R ¹ : alkyl having Ibis 5 C atoms, HR ² : alkyl having 1 to 8 carbon atoms, and also substituted by halogen, OH and carboxy or sulfo groups, wherein the compound in the latter two cases may also be present as betaine

X ^е : any inorganic or organic acid anion which is omitted in betaines, is contained in at least one emulsion and / or auxiliary layer.

2. The method according to claim 1, characterized in that the compounds of formula I are used in amounts of between 2 and 200mmol and the compounds of general formula II in amounts between 0.05 and 2mmol per mole of silver halide.

3. The method according to claim 1, characterized in that the compounds of the formula I and II are introduced into emulsion and / or auxiliary layers.

4. The method according to claim 1, characterized in that the compounds of formula I are introduced as a dispersant in gelatin solution or dispersed together with the coupler.

5. The method according to claim 1, characterized in that the emulsion S-methyl-T-hydroxy-LS ^ - triazaindolizine is added.

Field of application of the invention

The invention relates to a method for stabilizing and preventing fogging in photographic materials based on silver halide emulsions which, during their preparation, contain stabilizing and fog-inhibiting additives.

Characteristic of the known technical solutions

In the development of exposed halogen silver materials, in addition to the desired silver or dye image, an additional so-called "fog", which is caused by influences in the preparation of the emulsion, storage and processing, is known to occur.

In order to prevent or reduce this fog, emulsion stabilizers or antifoggants are used, and sensitivity loss is often unavoidable. A good stabilizer is 5-methyl-7-hydroxy-1,3,4-triazaindolizine (hereinafter called "triazaindolizine") which, inter alia, does not reduce sensitivity.

A color halide silver halide material, in contrast to black and white materials, consists of a greater number of very thin layers containing high levels of couplers and silver halide to achieve high color densities. Such emulsions readily form fog during processing, especially when development is carried out at elevated temperature, ie above 30 ° C. Under these conditions, triazaindolizine and most known antifoggants are not sufficiently effective.

It is known that the color haze can be reduced by the addition of certain hydroquinone derivatives (eg, Dt-OS 2149789) which react with the diffusing developer-oxidation product, but also their effect is not sufficient. They have therefore been combined with antifoggants from the known group of heterocyclic mercapto compounds (for example Dt-OS 2034064, GB-PS 1 522 673), but with a good fog reduction, the desensitizing effect typical of these substances occurs.

As another group of antifoggants, quaternary salts, e.g. Benzthiazole (eg Dt-OS 1472 774); in the present case, however, they are unable to keep the fog sufficiently low.

Object of the invention

The object of the invention is the fog reduction in both fresh and stored color photographic silver halide material, especially when using elevated processing temperatures, without the sensitivity is lowered.

Explanation of the essence of the invention

The invention has for its object to find suitable as an additive to color emulsions compounds that allow, especially when using elevated processing temperatures, stabilization and anti-fog without desensitization.

This object is achieved according to the invention by using combinations for stabilizing and preventing fogging in photographic halogen silver materials, consisting of compounds of general formula I,

OH

(R)

OH

in the

n: 1 to 4,

R: identical or different, straight-chain or branched alkyl groups having a total carbon number for all R

from 5 to 40, and from compounds of general formula II,

in the

Z: atomic grouping to complete an optionally substituted aromatic system,

R ': alkyl of 1 to 5 C atoms, H

R ² : alkyl having 1 to 8 carbon atoms, also substituted by halogen, OH and carboxy or sulfo groups, wherein the

Compound in the latter two cases may also be present as betaine, X ": any inorganic or organic acid anion (not applicable to betaines)

mean.

A particular advantage of the invention is that the claimed combination in addition to the considerable fog reduction - unlike many other stabilizers and clearers - does not cause desensitization. The compounds may be added to any emulsion or to an auxiliary layer. The addition can be made at any time between the end of the Nachreife and pouring the emulsion.

Another advantage of the invention is that the substances together with other stabilizers, for. B. triazaindolizine can be used. They can be introduced into any emulsions (e.g., Ag Br I, Ag Cl Br emulsions) which contain, in addition to color couplers, chemical and spectral sensitizers, curing agents, wetting agents, and other photochemical additives. The color couplers may preferably be hydrophobic fatty radical couplers or hydrophobic oil couplers (cf H.Böttcher uGWest, Mitt.-BI.Chem. Ges., DDR 26,151 [1979]; K. Venkata raman, The Chemistry of Synthetic Dyes, New York / London, 1971 , Vol.4, p.356 ff.).

The introduction of the quaternary salts II into the emulsion takes place by addition of the aqueous or alcoholic solution, while the hydroquinones I are dispersed either alone or together with the color coupler in gelatin solution and added in this form to the emulsion. Analogously, the introduction takes place in auxiliary layers. The amount of hydroquinones I used in the emulsion is between 2 and 200, preferably 5 and 100 mmol, of the quaternary salts II between 0.05 and 5, preferably 0.1 and 2 mmol per mole of silver halide.

The particularly advantageous effect of the combination is surprising and unforeseeable, since the individual constituents I and II do not sufficiently reduce the fog, and indicates different mechanisms of action of both substance classes. The compounds claimed according to the invention can be prepared by known methods:

The alkylhydroquinones I (see Houben-Weyl, Methods of Organic Chemistry, 4th ed., Bd. 6/1 с [1976]) are formed

a) by alkylating hydroquinone with olefins or alcohols under acid catalysis,

b) by acylating hydroquinone and reducing the acyl to alkyl groups,

c) by reduction of the corresponding alkylquinones.

The thiazolium salts II are prepared by reacting the corresponding thiazoles with alkylating agents such as alkyl halides and sulfates or alkanesulfonates and sulfones (cf R.C. Elderfield, Heterocyclic Chemistry, Vol.5 [1957], U.S. Patent No. 2503776).

After the methods mentioned z. B. the following substances: Verb. Ill: n-Dodecylhydroquinone (F. 104 ⁰ C)

Comp. IV: 2.5-di-tert-butylhydroquinone {F. 215 "C)

Comp. V: 2,5-bis- (1,1-dimethylpropyl) -hydroquinone (mp 179 ⁰ C)

Verb.VI: 2,5-bis- (1,1-dimethylbutyl) -hydroquinone (F.111 ° C)

Comp. VII: 2,5-bis (1-ethyl-1-methylpropyl) -hydroquinone (F.147 ° C)

Comp. VIII: 2,5-bis (1,1,3,3-tetramethylbutyl) hydroquinone (F.125 ° C)

Comp. IX: 3-methylbenzothiazolium iodide (m.p. 207 X)

Comp. X: S-f-carboxymethyl-benzthiazolium bromide (F, 258 ° C)

Verb.XI 2.3-Dimethylbenzthiazoliumperchlorat (F. 124 ⁰ C)

Comp. XII: 3- (4-sulfobutyl) benzthiazolium betaine (F.267 ° C)

The following compounds are mentioned as comparative substances in the examples: Comp. XIII: i-phenyl-5-mercaptotetrazole Comp. XIV: 2-mercaptobenzimidazole-5-sulfonic acid

Execution examples

The invention is explained in more detail below by way of examples, wherein the additives Ill-XII claimed according to the invention and the comparison substances XIII and XIV have the abovementioned meaning.

example 1

An ammoniacal gelatin silver bromide iodide emulsion for color-positive, which was chemically sensitized with gold compounds, is divided into 5 parts and receives as additives per mole of silver halide successively 27 mmol Triazaindolizin, the amounts indicated in Table 1 of compound IX, 135g of the yellow coupler p -Stearoylaminobenzoyl-acetate-o-chloroanilide as an approximately 7% dispersion in gelatin solution in which the amounts of compound IV shown in Table 1 were dispersed, and the other conventional additives.

After casting onto a substrate, the resulting photographic material is cut into strips which are exposed behind orange and gray filters and wedge and developed in the following high-temperature developer for 3 min. At 36.8 ° C:

Ethylenediamine tetraacetic acid di-Na salt 1 g

Na ₂ SO ₃ 4.35 g

г-Атіпо-б-аіеігіуІатіпоіоІиоІ-гіугігосгіІогіа 2,95 g

Na ₂ CO ₃ 17.1 g

KBr 2 g

filled with H ₂ O to 1.

After further processing (stop bath, bleaching bath, fixer, washing), the levels are measured. The results (logarithm of the relative sensitivity at density 1.0 above the fog) where larger numbers of lower sensitivity and differences of 0.3 correspond to one diaphragm; Minimum density D _min ) are given in Table 1.

It can be seen that each of the two substances IV and IX alone, with appropriate dosage significantly reduces the fog, but that with the combination of both substances, an extremely low fog value is achieved. The sensitivity and also the gradation are not adversely affected.

Example 2

An emulsion as in Example 1 is divided into 16 parts and receives as additives per mole of silver halide successively 27 mmol triazaindolizine, the amounts indicated in Table 2 of compound IX and III to VIII (the latter as about 2% dispergate in 5% gelatin solution or as an additive to the coupler dispersion),

107 g of yellow coupler XV

Cl

(CH ₄ KC-CO-CH-CO-Nh- / \

0 ⁴ NH-SO ₂ -C ₁₅ H ₃₃ (n)

! xv

OCH ₂ C ₆ H ₅

as about 7% dispersion in gelatin solution and the other usual additives.

After casting onto a substrate, the material is cut into strips which are exposed behind orange and gray filters and wedge and developed in the developer of Example 1, 2, 3 or 4 min. At 35 ° C. The results obtained after further processing and measuring are given in Table 2 analogously to Example 1.

It can be seen from the table that each of compounds III to VIII significantly lowers the fog, with the effect being enhanced with increasing dosage to a level of 36mmol per mole of silver halide (sample 5-8). The combination with Compound IX, which itself is a good antifoggant (Sample 2), further reduces the fog to levels of 0.07-0.10 (2 min.). The sensitivity is not significantly affected.

Example 3

The procedure is as in Example 2, with the difference that the emulsion is divided into undТеіІе and are added as anti-veiling substances the amounts of the compounds VIII and IX to XIV mentioned in Table 3. The results are shown in Table 3.

It can be deduced from this that, in combination with the dialkyl hydroquinone VIII, each of the quaternary salts IX to XII lowers the fog sufficiently; the sensitivity is not lowered when the quaternary salts are used in concentrations up to about 0.45 mmol per mole of silver halide. The already known combinations of VIII with the mercapto compounds XIII and XIV (samples 9 and 10) have a desensitizing effect, with XIV also not acting sufficiently as a veiling agent.

Example 4

M proceeds as in Example 2, with the difference that the emulsion is divided into 9 parts and the amount of compounds IX and VIII shown in Table 4 are added as anti-fogging substances, the latter either as an approximately 2% dispergate in 5 % Gelatinellösung (Dispergat A) odeer or as an additive to the Kupplerdispergat (Dispergat B) are introduced. The sensitometric data presented in Table 4 show that these are independent of the mode of incorporation of the alkylhydroquinone VIII.

Example 5

A gelatin-silver chlorobromide emulsion for color-positive which has been chemically sensitized with gold compounds is divided into 2 samples. Sample 1 as additives per mole of silver halide successively receives 900 mg of triazaindolizine, 60 mg of the red sensitizer Rr 1953 (see K. Venkataraman, The Chemistry of Synthetic Dyes, New York 1952, Vol 2, p 1180), 230 g of cyan coupler XVI

ОН

Cl I NH-CO-CH-O- / Л-С _С Н ", (tert.)

\ ^ Ѵ '\ -J ^{5 п}

^С 2 ^Н 5; хѵі

AC ₅ H _{ll (} tert.)

CH-,

⁰ Cl

as about 7.5% dispersion in gelatin solution and the other usual additives.

In addition to the additives mentioned above, sample 2 also receives, after the spectral sensitizer, 0.72 mmol of substance IX and (as an approximately 3% dispersion in gelatin) 27 mmol! Substance VIII per mole of silver halide.

After casting, strips are exposed either fresh or after heating cabinet storage (7 days at 50 ° C) behind orange and gray filters and wedge and processed and evaluated as in Example 2 (Table 5). Compared to Sample 1 (without antifoggant, Sample 2 has low fog levels, favorable veiling kinetics with extension of development time, and good oven stability.) Also noteworthy is the increase in gradation g by the added antifoggants.

Example 6

A gelatin silver bromide emulsion for color positive which has been chemically sensitized with gold compounds is divided into 2 samples. Both are obtained as additives per mol of silver halide in succession 900 mg of triazaindolizine, 180 mg of the green sensitizer 9-ethyl-3,3'-bis- (4-sulfobutyl) -5,5'-diphenyl-oxatrimethine cyanine mono-Na salt (cf. PS 929080), 140g of the purple coupler XVII as about 5% dispersion in gelatin solution and the

(Η)

XVII

other usual additives.

In addition to the additives just mentioned, in each case after the spectral sensitizer, 0.3 mmol of the known antifoggant XIII, to sample 2 0.5 mmol of the substance IX and (as a 3% dispersion in gelatin) 12 mmol of the substance VIII added per mole of silver halide. Processing and evaluation (Table 6) are carried out as in Example 5. Again, one recognizes the considerable Schleiersenkung by the antifogging agent contained in sample 2, while the used in sample 1, already known substance is not sufficiently effective.

Example 7

A color photographic multilayer material for color-positive with interchangeable layer sequence contains the following layers:

a) as an infusion, an emulsion as in Example 2, which is added as an antifoggant 0.45 mmol of substance IX and (asca.3% dispergate in gelatin solution) 18 mmol of substance VIII per mole of silver halide and the other additives mentioned in Example 2,

b) a gelatine interlayer,

c) as an intermediate casting an emulsion as in Example 5, to which all additives of sample 2 in Example 5 are added,

d) an intermediate gelatin layer,

e) as a topping an emulsion as in Example 6, to which all additives of sample 2 in Example 6 are added,

f) a gelatin coating.

The procedure is as in Example 5, with the difference that the strips are measured after processing separately behind filters of the respective complementary color for the spectral ranges, and receives the sensitometric data given in Table 7, where b, g and r are the data the blue, green or red-sensitive layer called. In all 3 layers of the described material, the used antifoggant combination results in extremely low fog levels, very good veiling kinetics with extended development time, and good oven behavior.

Example 8

An ammoniacal gelatin silver bromoiodide emulsion for color negative which has been chemically sensitized with gold compounds is divided into 2 parts. The sample 1 used as a type receives as additives per mole of silver halide successively 340 mg of triazaindolizine, 250 mg of the red sensitizer 5.5'-dimethyl-9-ethyl-3- (2-hydroxyethyl) -3 '- (3-sulfopropyl) -thiacarbocyanine betaine (see DD PS 11108, Example 6), 36 g of the cyan coupler XVIII as an approximately 7% dispersion

_С Н (

5 li

XVIII

tert)

in gelatin solution and the other usual additives.

In addition to the above-mentioned additives, sample 2 also receives 0.35 mmol of substance IX and 40 mmol of substance VIII (last as about 3% dispersion in gelatin solution) per mole of silver halide, after the spectral sensitizer.

After casting, the photographic material is cut into strips which are exposed behind yellow filter and step wedge (factor 2) and developed in the following high-temperature developer for 3.25 min. At 37.8 ° C.:

Ethylenediamine tetraacetic acid di-Na salt 2 g

Hydroxylamine sulfate 2 g

2-amino-5- (ethyl-β-hydroxyethylamino) -toluene 4.8 g

K ₂ CO ₃ 30 g

Na ₂ SO ₃ 3.8 g

KBr 1.8g

KH CO ₃ 3.5 g

filled with H ₂ O to 1.

After further processing (stop bath, bleach, fixer, watering), the strips are measured. The results (relative sensitivity at density 1.0 above fog in stops, with larger numbers correspond to lower sensitivity, minimum density D _{m, n} and gradation g) are given in Table 8 below.

The antifog additive adds significant fog control without compromising sensitivity.

Table 1

Sample supplement (mmo [/ molAgHal

Verb. IV verb. IX

18 36

36

0.45 0.45

not measurable 0.83 not measurable 0.48 1.1 0.30 1.2 0.14 1.2 0.07

Table 2

sample

Addition (mmol / mol Ag Hai

2 '3'

4 '

Verb IH-VIII verb. IX

Ig E _1-0

D _min

ig

1 - 2 _ 3 III (24) 4 III (24) 5 IV (9) 6 IV (18) 7 IV (27) 8th IV (36) 9 IV (18) 10 IV (36) 11 V (36) 12 V (36) 13 VII (36) 14 VII (36) 15 VIII (27) 16 VIII (27) Table 3

0.45 0.45

0.45 0.45

0.45 0.45 0.45

1.7

1.7

1.65

1.7

1.6

1.65

1.65

1.65

1.7

1.75

1.6

1.7

1.65

1.7

1.7

1.75

0.41 0.12 0.12 0.08 0.24 0.13 0.13 0.12 0.08 0.07 0.10 0.08 0.13 0.10 0.14 0.07

not measurable 1.24 1.5 0.36 1.5 0.35 1.55 0.13 1.5 0.50 1.5 0.48 1.5 0.38 1.55 12:34 1.5 0.18 1.4 0.10 1.4 0.33 1.5 0.18 1.55 0.32 1.5 0.20 1.5 0.42 1.55 0.12

not measurable 2.10 not measurable 0.67 not measurable 0.73 1.3 0.23 not measurable 1.45 not measurable 1.11 not measurable 0.84 not measurable 0.56 1.3 0.24 1.3 0.16 1.25 0.61 1.25 0.27 not measurable 0.71 1.35 0.30 1.3 0.61 1.35 0.19

sample

Addition (mmol / mol Ag Hai.

2 '3'

4 '

Verb. VIII Verb. IX-XIV Ig E ,. _o D _rar "

Ό Ei.o

1 2 3 4 5 6 7 8 9 10

24 24 24 24 24 24 24

1.7 IX (0.45) 1.7 IX (0.9) 1.75 IX (0.45) 1.7 IX (0.75) 1.75 X (0.45) 1.7 Xl (0.45) 1.75 XII (0.45) 1.7 XIII (0.45) 2.0 XIV (0.45) 1.8

0.49 0.15 0.12 0.08 0.08 0.12 0.11 0.10 0.10 0.20

not measurable 1.07 1.5 0.34 1.6 0.25 1.5 0.16 1.55 0.10 1.5 0.22 1.55 0.20 1.55 0.19 1.8 0.15 1.7 0.29

not measurable 1.92 not measurable 0.62 1.4 0.44 1.35 0.26 1.4 0.19 1.3 0.40 1.35 0.28 1.3 0.29 1.55 0.28 1.55 0.60

Table 4

sample

Addition (mmol / mol Ag shark.)

2 '

3 '

4 '

Verb. VIII Verb. IX Ig E _1-0 D _m ; " L'min U min (Disp.) 1 _ _ 1.6 0.37 1.13 2.25 2 18 (A) - 1.55 0.15 0.40 0.95 3 36 (A) - 1.6 0.13 0.32 0.90 4 18 (B) - 1.55 0.13 0.41 0.95 5 36 (B) - 1.6 0.11 0.29 0.79 6 18 (A) 0.45 1.55 0.10 0.28 0.66 7 36 (A) 0.45 1.5 0.09 0.21 0.62 8th 18 (B) 0.45 1.55 0.09 0.26 0.60 9 36 (B) 0.45 1.6 0.09 0.21 0.55

Table 5

IgE _1-0 2 ' G lgE _li0 3 ' G igEi.o 4 ' G 3 ' fresh G 3 'Heizschr. Dmin G sample 1.7 1.7 Dmin 3.3 4.0 1.65 1.6 Dmin 3.7 4.1 1.6 1.45 Dmin 3.6 4.4 IgEi _-0 Dmin in ел co "co" IgE _1-0 0.56 0.17 3,2 3,5 1 2 0.17 0.06 0.30 0.07 0.54 0.12 1.7 1.55 0.34 0.08 1.6 1.45

Table 6

IgE _1-0 CN G IgE _1-0 3 ' G IgE _1-0 4 ' G 3 ' fresh G 3 'Heizschr. Dmin G sample 1.7 1.7 Dmin 2.5 2.7 1.7 1.65 Dmin 2.6 2.8 1.6 1.65 Dmin 2.8 2.9 IgE _1-0 Dmin JO JO "со" ел IgE _1-0 0.30 0.10 2,2 2,4 1 2 0.14 0.06 0.28 0.08 0.41 0.10 1.65 1.65 0.27 0.07 1.5 1.45

Table 7

IgE _1-0 2 ' G IgEw 3 ' G IgEi.o 4 ' G 3 ' fresh G 3 ' Heizschr. G layer 1.75 1.7 1.85 Dmin 2.3 3.2 4.2 1.55 1.6 1.7 Dmin 3,4 3,7> 4,5 1.45 1.5 1.6 Dmin 4.0 4.0> 4.5 IgE _1-0 Dmin 3.4 3.5 4.3 IgE _1- C , Dmin 2.9 3.3 4.2 b g r 0.09 0.06 0.06 0.09 0.07 0.06 0.11 0.12 0.07 1.5 1.55 1.7 0.09 0.06 0.05 1.55 1.6 1.8 0.10 0.07 0.06

Table 8

sample

5.6 5.5

0.48 0.18

JJ

0.60 0.70

Claims (1)

claims: 1. A method for stabilizing and preventing fogging in color photographic silver halide materials, characterized in that a combination of compounds of general formula I, OH « ^R » n