DE2306272C3 - Process for the preparation of aqueous-alkaline photographic color developer solutions and developer concentrate for carrying out the process - Google Patents

Description

a) an organic phosphonic acid of the formula:

ORO

Il I Il

HO-P-C-P-OH

OH OH OH

in which R is an alkyl radical with 1 to 5 carbon atoms

b) a water-soluble salt of the acid or

c) a water-soluble mono- or dialkyl ester of the acid with methanol, ethanol, propanol or butanol

are bound complex, characterized in that the color developer solutions under Addition of a water-soluble lithium compound can be used.

2. Developer concentrate for carrying out the method according to claim 1 with a content of I. at least one water-soluble sodium and / or potassium salt and II .:

a) an organic phosphoric acid of the formula:

ORO

Il i Il

HO-P-C-P-OH

I I

OH OH OH

in which R is an alkyl radical with 1 to 5 carbon atoms

b) a water-soluble salt of the acid or

c) a water-soluble mono- or dialkyl ester the acid with methanol, ethanol, propanol or butanol,

characterized by a content of a water-soluble lithium compound.

3. developer concentrate according to claim 2, characterized in that it is the lithium compound in a concentration corresponding to a lithium ion concentration of the ready-to-use aqueous Color developing solution contains from 0.010 to 0.2 moles / liter.

4. developer concentrate according to claims 2 and 3, characterized in that it contains the lithium compound in such a concentration that the Weight ratio of lithium ions to sodium and / or potassium ions is at least 0.02: 1.

5. developer concentrate according to claim 2, characterized in that there is also one Contains color developing agent.

6. developer concentrate according to claim 5, characterized in that it is used as color developer

ethyl] -m- (oluidine, sesquisulfal monohydrate contains.

7. developer concentrate according to claim 2, characterized in that there is also a Contains sulfate ion-producing compound, hydroxylamine sulfate and / or benzyl alcohol

8, developer concentrate according to claim 2, characterized in that the remainder R is the Phosphonic acid is a methyl group

The invention relates to a method for preparation Aqueous-alkaline photographic color developer solutions, whose alkalinity at least partially with the aid of water-soluble sodium and / or potassium compounds is set and in the bivalent and trivalent metal ions by adding

a) an organic phosphonic acid of the formula:

ORO

Il I Il

HO — Ρ — C — Ρ — OH

i I

OH OH OH

in which R is an alkyl radical with 1 to 5 carbon atoms

b) a water-soluble salt of the acid or

c) a water-soluble mono- or dialkyl ester of Acid with methanol, ethanol, propanol or butanol

complex. The invention also relates to a developer concentrate for carrying out the method.

It is generally known, for example from US Pat. No. 3,214,454, to prepare chelating agents by acylation of phosphorous acid and to use the reaction products To use complex binding of metal ions, in particular polyvalent metal ions.

It is also well known e.g. B. from the DE-OS 14 47 710,2018 096 and 20 50 699, photographic developer solutions, chelating agents, often also Add as sequestering agent or limescale protection agent to prevent the formation of precipitates avoid.

However, it has been shown that the known chelating agents have more or less serious disadvantages when used in color developing solutions exhibit. This also applies to organic phosphonic acids of the formula given under a). Will Phosphonic acids of the formula given under a) as Chelating agents for binding complexes of, for example, calcium ions in alkaline color developer solutions, which contain sodium and / or potassium ions, used so falls and after a short time Period of time, a characteristic white precipitate that adversely affects the properties of the too developing photographic material.

The object of the invention is to provide a process for the preparation of aqueous-alkaline photographic color developer solutions of the type specified at the outset should be specified which, when carried out, avoids the excretion of a white precipitate.

According to the invention, the object is achieved in that, in a method of the type specified at the outset, the color developer solutions starting from the usual substances with the addition of a water-soluble lithium compound.

A is suitable for carrying out the process

Developer concentrate with a content of L at least one sodium and / or soluble in water Potassium salt and II.

a) an organic phosphonic acid of the formula;

ORO

Il I Il

HO-P-C-P-OH

OH OH OH

in which R is an alkyl radical with 1 to 5 carbon atoms,

b) a water-soluble salt of the acid or

c) a water-soluble mono- or dialkyl ester of Acid with methanol, ethanol, propanol or Butanol,

which is characterized by a content of a water-soluble lithium compound

Will be used to carry out the procedure or to Preparation of the developer concentrates using water-soluble salts of phosphonic acid of the structural formula given, these can, for example, from Alkali metal, ammonium and ethanolamine salts exist.

Preferably, the lithium compound is used in such a concentration that the color developing solution is at least 0.010 moles per lithium ion Liters of solution

The methods for carrying out the process of the invention and for preparing the design concentrates of Chelating agents used in the invention can be obtained by reacting phosphorous acid with organic Acid anhydrides and / or acid chlorides, in particular the vinegar, propionic, butter, valerian and Caproic acid. If both an acid anhydride and an acid chloride are used for the acylation, so must they be derived from the same acid, d. H. to the Carrying out the Acyüerungsreaktion, for example, the anhydride and the chloride Acetic acid can be used, but not, for example, acetic anhydride and propionyl chloride at the same time. Instead of phosphorous acid and one of the specified acid chlorides can also phosphoric acid trichloride with one of the specified carboxylic acids implemented. The reaction products of phosphorous acid with acetic anhydride, with acetyl chloride or mixtures are particularly easily accessible of this. Conveniently, the reactions at elevated temperature, preferably at a Temperature from 50 to 2 (XTC performed.

It has proven to be useful (see also the information in US Pat. No. 32 14454) to use the chelating agents in Use concentrations of from about 0.0002 moles to about stoichiometric amounts based on the total concentration of polyvalent metal ions.

The concentration of lithium ions is preferably such that there are 0.010 to 0.2 moles of lithium ions per liter of color developer solution. Below the specified lower concentration range, i.e. H. if lithium ion concentrations below 0.010 moles are used, the lithium ion concentration may be too low to cause the precipitate to occur to avoid a precipitate, whereas at concentrations above the specified above Concentration range occasionally undesirable sensitometric effects can occur, so that the Use of higher concentrations of Uthhwnionen can be inexpedient.

A wide variety of lithium compounds can be used, for example lithium sulfate, lithium sulfite and Lithium hydroxide. In the case of photographic? Color developer solutions, the ions of which are precisely matched to one another, can be useful, a lithium salt

ίο to use whose anion is a common one for the system Anion that is compatible with the solution. For example, a carbonate buffer in a solution is used, lithium carbonate is advantageously used as the lithium compound Color developing solution containing a borate buffer, the lithium compound is advantageously used, e.g. B. used as lithium hydroxide In a corresponding manner, lithium sulfate is advantageously used used when the color developing solution is hydroxyl amine sulfate contains As it is usually useful in To maintain a low concentration of halogen ions in color developing solutions, the addition of Lithium cations in the form of lithium chloride, lithium bromide or lithium iodide occasionally lead to undesirable th sensitometric effects. In other cases, however, where halogen ions lead to none The lithium ions can lead to adverse effects on the other hand, they can be used safely in the form of halogen salts.

Although the concentration of lithium ions in the color developing solutions can vary widely, particularly advantageous results are obtained when the ratio of lithium ions to other alkali metal ions in the solution at about 0.1: 1 up to 10: 1. With such lithium ion concentrations, a precipitate can be deposited practically completely avoid. In a particularly advantageous manner, the weight ratio of lithium ions to sodium and / or potassium ions is at least ens 0.02: 1, especially at least 0.05: 1.

Although the process of the invention can be used to prepare a wide variety of aqueous alkaline photographic color developing solutions with a wide variety divalent and trivalent metal ions, for example of the following ions: Mg + ² , Ca + ² , Cu + ² , Zn ⁺² and Fe + ³ , is applicable, particularly advantageous results are obtained in those cases in which it is necessary ^{to bind calcium ions (Ca + 2} ) complex, since in the case of The presence of calcium ions leads to the formation of a precipitate (in

so absence of lithium ions) particularly quickly he follows

The way in which the addition of lithium ions prevents the precipitation of a precipitate has not yet been fully clarified. It is assumed that in solutions containing polyvalent metal ions, e.g. B. ions of the type Ca + ² and Cu + ² , a chelating agent of the specified type and alkali metal ions other than lithium ions, for example sodium and / or potassium ions, a mixed complex Alkali metal ions, polyvalent ions and the chelating agent is formed and that it is this mixed complex is that fails. This means that, for example, in the case of solutions, the sodium and calcium ions contained, the precipitate from the disodium mono-

hi calcium salt of the chelating agent is formed. In the In cases in which both sodium and potassium ions are present in the solution, precipitates from the disodium, dipotassium or mono-sodium

wn-monopotassium monocalcium salts of the chelating agents be generated.

The lithium compounds required to carry out the method of the invention can be a constituent more commonly known concentrates such as those used in the preparation of photographic color developer solutions be used. If the lithium compounds are added to concentrates, it has proven to be expedient proved to add the lithium compounds in the case of concentrates that consist of several concentrate components to the concentrate components.

10

with which the lithium compound is most compatible. The invention thus enables, for example, the Modification of developer concentrates from the US-PS 36 15 497 known type.

In general, it has been found useful that the To add lithium compound to the part of the developer concentrate that contains the color developer compound This part of the developer concentrate is, for example, part c) of Examples 5 and 15 or part D) of Example 2 of U.S. Patent 3,615,497.

example 1 (Comparative example)

First, a photographic color developer solution was prepared which contained per liter of solution: Hydroxylamine sulfate Benzyl alcohol

one the formation of discoloration

preventing connection *)

NaBr

Na ₂ SO ₃ , anhydrous K2CO3, anhydrous

a color developer compound **)

NaHCO3 up to a pH value of

10.083 at about 27 ° C 3.4 g
14.5 ml
1.0 g
0.29 g
1.59 g
31.0 g
4 ^ 0 g

It

NH

C ₂ H ₄ OH C ₂ H ₄ SO ₃ Na NH

CH = CH- ^ O> -NH- < O N

NO> -NH

OCH ₃ SO ₃ Na SO ₃ Na OCH ₃

**) 4-Amino-N-ethyI-N- (methanesulfonamido-ethyl) -iD-toluidine-sesqiiisuIfatmooohydraL

The solution was used to develop color images

For various proportions of the fresh solution, those listed in the following table were then added Amounts of calcium ions and chelating agents added.

The results compiled in Table I below were obtained.

Table I.

60% aqueous solution of the chelating agent *)

Results after 38 days

0.0087 mol / L 0.0075 mol / L 0.0063 mol / L 0.005 mol / L 0.0037 mol / L

2 ml / L 2 ml / L 2 ml / L 2mI / L 2 ml / L

Precipitation Precipitation Precipitation Precipitation 40

50

55

Calcium ions when using the chelating agent described occurred after 38 days of precipitation.

Corresponding results were obtained if, instead of the chelating agent used, other Chelating agents of the formula given were used in which the methyl radical is replaced by an alkyl radical with 2 to 5 carbon atoms was replaced.

Example 2

First, an aqueous solution was prepared from 0.25 moles of K ₂ CO ₃ , 1 ml of a 60% strength aqueous solution of the chelating agent mentioned in Example 1 and 100 ppm of Ca ⁺ + ions

The additives listed in Table II below were then added to this solution.

The approximate weight of the precipitation that had formed after 10 and 17 days was determined.

Table II

additive

O O

Ii I 11

HO-P-C-P-OH

HO I HO HO

The results obtained show that in all cases, ie at different concentrations of 60

Precipitation after 10 days

Rainfall after 17 days

0.01 M Na ₂ CO., 0.704 0.790

I g / l potassium hexa- 0.715 0.810 metaphosphate

0.05MLi ¹ <0.001 0.006

0.05 M Rb '~, 700 0.844

0.05 M Cs ¹ 0.800 -.700

From the above examples it can be seen that the addition of small amounts of lithium ions Formation of a precipitate is avoided. Table II also shows that with rubidium ions and cesium ions, the effect that can be achieved with lithium ions is not achieved.

Example 3

Further experiments were carried out with an aqueous 0.25 molar K ₂ CO ₃ solution which contained 1 ml of a 60% strength aqueous solution of 1-hydroxyethylidene-1,1-diphosphonic acid per liter.

The effect of the addition was determined before lithium ions for the purpose of avoiding precipitation Calcium complexes of the chelating agent in a photographic color developing solution with various Concentrations of sodium ions and a concentration of 0.5 mol of potassium ions as well as one molar Concentration of the chelating agent of 0.003 M = 1 ml / Liters of a 60% aqueous solution of the chelating agent concentrate.

The results obtained by examining these solutions are summarized in Table III below posed.

Table III

N / A
Ca '

Ions
Kon /.

0.2 M
(). (X) 25 M.

0.005 M.

0.1 M.
0.0025 M.

0.1X15 M 0.04 M
O. (X) 25 M.

0.05 M

0.02 M
0.0025 M.

0.05 M

0.2 M
0.1 M.
0.04 M
0.02 M
0.0OM

Kon /.

48 days

13 days

13 days

2 days

160 days

20 days

20 days

6 days

183 days

48 days 48 days

20 days 48 days

7 days 19 days

195 days

132 days

60 days

202 days
92 days

233 days

*) No precipitation after 150 days.

From the above Table III it can be seen that the formation of a precipitate from a mixed complex from chelating agents and sodium and calcium ions is avoided when the concentration of lithium ions is at least equal to the concentration of sodium ions in the developer solution.

At a calcium ion concentration of 0.0025 mol, for example, the first visible lower crhlsnT according to Ptwa 181 Τασρη occurs when 1 MnIp sodium ions and 0.1 mol lithium ions are present. If the concentration of lithium ions is reduced to 0.04 moles, the first excretion takes place after about 48 days. It can be seen from the table that the greatest tendency to precipitate is present when no lithium ions are present, and that the greatest prevention of precipitation can be observed when the concentration of lithium ions is approximately the same as the concentration of sodium ions or the concentration of Sodium ions in the developer solution.

The results compiled in Table III can also be evaluated in another way, namely when you use the values listed in the table Then compares numerical data not in the vertical but in the horizontal direction it follows that the formation of a precipitate can be delayed more and more, the less the The concentration of sodium ions in the developer is The two factors apply to the most diverse Sodium and lithium ion concentrations. The bars in Table III indicate that there is no precipitate could be determined. The total attempt time was 233 days.

It should be noted that the improvements in precipitate formation were also observed can be if the ratio of lithium ion egg to sodium ions liegl at 0.02 mole: 0.2 mole Whereas in the absence of lithium ions a precipitate is formed within 2 days (see column 2), the addition of 0.02 Molei delays Lithium ions the first signs of precipitation around 13 days. If the sodium ion concentration is high The tendency for precipitation to form can be suppressed for 1/7 of a year or more provided that at least equimolar amounts of lithium ions are present. A considerable over-school of lithium ions in the color developer solutions, the tendency towards the formation of precipitates continues to increase.

The following examples illustrate the manufacture of color developer concentrates with various those concentrations of lithium ions.

Example 4

A color developer concentrate was prepared from the following three components A), B) and C)

Component A) consisted of a dispersion of benzyl alcohol according to Example 3 of US-PJ 36 15 497.

Component B) corresponded to part B) de: Example 5 of US Pat. No. 3,615,497 and contained chelate image ner.

Component C) consisted of:

Color developer compound) 430 g Li ₂ SO ₄ 0.55 g SO3- - in the form of Na2S2Os 0.13 g water 12.21 ml

1,542 mi

*) 4-Amino-N-ethyl-N (0-methanesulfonamidoethyl) -m-to luidine sesquisulfate monohydrate

A ready-to-use color developer solution was made from the concentrate by combining components A), B) and C) and adding so much water produced so that a total volume of 1 liter was reached. The color developing solution was 0.01 molar in terms of lithium ions.

A color developer concentrate of the specified type can also be used as a so-called supplementary concentrate Use to supplement color developing solutions. In this case, the total amount of component C) can be increased by about 21% to about 18.77 ml will.

Example 5

Another color developer concentrate was prepared from components A), B) and C) Components A) and B) corresponded to components A) and B) of Example 4. Component C) ucMariu au:>

Color developing agent

Li ₂ SO ₄

SOi - in the form of

water

4.30 g

1.78 g

0.13 g

12.21 ml

15.52 ml

After combining the three components and adding water up to a total volume of 1 liter, the developer solution was 0.03 molar in terms of lithium ions.

When the concentrate is used to supplement color developing solutions, the total amount becomes of component C) appropriately increased by 21% to 18.77 ml.

The color developing agent consisted in this example as well as in Example 6 below 4-Amino-N-ethyl-N (/? - methanesulfonamidoethyl) -m-toluidine-sesquisulfate monohydrate.

Example 6

Another color developer concentrate was prepared from three components A), B) and C). The Anenlon Δ \ ttrxr \

on αΐηο 7ti

tion as indicated in Examples 4 and 5. Component C) consisted of

Color developing agent

Li ₂ SO ₄

SOj ^ - in the form of Na

water

4.30 g 11.00 g

0.13 g 46.90 ml 52.54 ml

After combining components A), B) and C) and filling up with water to a total volume of 1 liter was the solution with regard to lithium ions O ^ molar.

If this color developer concentrate is used to supplement developer solutions, the Total amount of component C) can be increased in an advantageous manner by 21% to about 63.54 ml.

Results corresponding to those described in Examples 2 to 6 were obtained when instead of the Chelating agents of the formula given in Example 1, chelating agents of the formula given are used in which the methyl radical is replaced by an alkyl radical with

ίο 2,3,4 or 5 carbon atoms was replaced.

Example 7 (comparative example)

The effectiveness of various known i) chelating agents in common color developer solutions, e.g. B. the composition given in Example I, compared with one another. The following were examined:

1 Natriitmhpxametanhnsnhat

2. Sodium tetraphosphate

3. Sodium (ethylenedinitrilo) tetraacetate

4. Sodium nitrilotriacetate

5. Sodium diethylenetriamino pentaacetate

6. 1,3-diamino-2-propanol tetraacetic acid , .- 7. Sodium Nitrilotri (methylene phosphate)

8. 1,2-diamino-cyclohexanetetraacetic acid 9. *) 1 - hydroxyethylidene-1,1-diphosphonic acid. ') According to the invention.

in As criteria for the effectiveness of the chelating agent served:

a) the ability to bind calcium ions,

b) the stability to hydrolysis by alkali,

c) causing unwanted photographic '"' see effects,

d) the acceleration of the breakdown of hydroxylamine,

e) easy accessibility and costs.

The following results were obtained:

Compounds 1 and 2 were easily hydrolyzed in the alkaline color developing solutions and thereby effective. The connections 3. 4. 5. 6 and 7 catalyzed the degradation of hydroxylamine, especially in the presence of iron salts. Only that

4-> Compounds 8 and 9 did not catalyze the breakdown of hydroxylamine. The connection 9 (according to the Invention), however, proved to be the more effective chelating agent than compound 8, i.e. for Binding of the same amount of calcium ions was the

-, o required amount of compound 9 is considerable less than the required amount of compound 8.

The deposition of white precipitates at Use of the compound 9 can, however, as in

shown in the previous examples by adding

Prevent lithium ions.

Claims (1)

Patent claims: 1. A process for the preparation of aqueous alkaline photographic color developer solutions, their Alkalinity is adjusted at least partially with the help of water-soluble sodium and / or potassium compounds and in the bivalent and trivalent metal ions by adding