Note: Descriptions are shown in the official language in which they were submitted.
55~
This invention relates in general -to color photograph~
and in particular to new and improved color developing compo-
sitions and processes for forming photographic color imagesO
More specifically, this invention relates to color development
with a color developing composition containing a primary
aromatic amino color developing agent and an hydroxylamine
salt which is stabilized by the presence of a combination of
sequestering agents~
The formation of color photographic images by the
image-wise coupling of oxidized primary aromatic amino develop-
ing agents with color forming or coupling compounds to form
indoaniline, indophenol, and azomethine dyes is well known. In
these processes, the subtractive process of color formation is
ordinarily used and the image dyes customarily formed are cyan,
magenta, and yellow, the colors that are complementary to the
primary colorsg red, green, and blue, respectively. Usually
phenol or naphthol couplers are used to form the cyan dye image;
pyrazolone or cyanoacetyl derivative couplers are used to form
the magenta dye image; and acylacetamide couplers are used to
form the yellow dye image.
In these color photographic systems, the color-forming
coupler may be either in the developer solution or incorporated
in the ligh~-sensitive photographic emulsion layer so that3
during development~ it is available in the emulsion layer to
react with the color developing agent that is oxidized by silver
image development. Diffusible couplers are used in color
developer solutionsO Nondiffusing couplers are incorporated
in photographic emulsion layers. When the dye image formed
is to be used in situ, couplers are selected which form non-
diffusing dyes~ For image transfer color processes, couplers
5~i3
are used which will produce dilfusible dyes capable of beingmordanted or fixed in the receiving sheet.
It is common practice in the photographic arts to
include an hydroxylamine salt in color developer compositions
containing primary aromatic amino color developing agents.
For example, hydroxylamine salts are used in color developers
as antioxidants and, as described in United States patent
3,141,771, an hydroxylamine salt can be incorporated in a
color developer to improve the properties of balancing develop-
ing agents. However, a problem is presented by the factthat the hydroxylamine salt tends to decompose in the developer
to generate ammonia and, as is well known, the ammonia can
produce adverse sensitometric effects such as the formation
of cyan stain in color photographic elements. As disclosed
- 15 in United States patent 2,875,049, the sequestering agent
1,3-diamino-2-propanol tetraacetic acid functions as a
stabilizer ~or developer compositions containing an hydroxyl-
amine salt. However, this sequestering agent is not effective
in preventing the decomposition of hydroxylamine salts in
developer compositions which contain heavy metals, such as
iron or copper, which function to catalyze the decomposition.
This is a significant limitation on the usefulness of this
sequestering agent in the photographic arts since it is common
for small amounts of heavy metals to be present in developers,
for example~ iron salts which are utilized in bleach or bleach-
fix compositions in many methods of processing photographic
e]ements can contaminate the color developer, or iron oxide
used in inks employed to mark indicia on photographic prints can
be deposited in color developers.
Disphosphonic acid sequestering agents, such as are
described in United States patent 3,214,454, can be employed
in color developer compositions and the sequestering agent
l-hydroxyethylidene-l,l-diphosphonic acid is, in particular,
very effective in preventing the decomposition of hydroxylamine
salts in developers containing heavy metals such as iron which
function to catalyze such decomposition. Use of hydroxyalkyl-
idene diphosphonic acid sequestering agents in neutralizing
baths which contain hydroxylamine salts in order to stabilize
the bath against decomposition of the hydroxylamine salt is
described in United States patent 3,647,449. However, when an
hydroxyalkylidene diphosphonic acid sequestering agent is
incorporated in a photographic color developer a problem
occurs in that such developers con-tain alkali metal ions such
as sodium or potassium ions and as a result a precipitate of
the hydroxyalkylidene diphosphonic acid sequestering agent
is formed. This precipitate is believed to be a salt o~ the
sequestering agent such as the disodium monocalcium salt or
the monosodium monopotassium monocalcium salt. This problem
of precipitate formation and a solution to the problem are
disclosed in United States patents 3,794,591 issued February
26, 1974 and 3,839,o45 issued October 1, 1974. The solution
to the problem which is disclosed in the aforesaid patents
is the incorporation of lithium ions in the developer solu-
tion, such as by the use of lithium carbonate or lithium
sulfate, whereby the formation of the precipitate is prevented.
However, this solution to the problem suffers from the dis-
advantage that addition of a lithium salt to the developer
composition adds substantially to the total cost~
~ '~` .
3~55763
In view of the facts described above~ it is apparent
that the prior art does not provide a fully satisfactory
solution to the problem of stabiliz:ing color developer
solutions which contain hydroxylamine salts and are contaminated
by heavy metals, such as iron, which catalyze the decomposition
of such salts. Thus, use of 1,3-diamino-2-propanol tetraacetic
acid by itself will result in a developer composition that
undergoes decomposition in the presence of heavy metals, such
as iron, to an extent that is undesirable. On the other hand,
use of 1-hydroxyethylidene~ diphosphonic acid by itself
will substantially prevent the decomposition but result in
undesirable formation of a precipitate and addition of the
lithium salt to the developer composition to avoid precipitate
formation will increase costs to an extent sufficient to hinder
the commercial utilization of the developer composition.
In accordance with this invention~ it has now been
discovered that the problem described above can be solved by
incorporating in the developer composition both 1,3-diamino-2-
propanol tetraacetic acid and a diphosphonic acid sequestering
agent. It has been unexpectedly discovered that the combination
of these two sequestering agents will significantly decrease
the extent of decomposition of hydroxylamine salts in color
developer compositions, even when such compositions contain
heavy metals such as iron which catalyze the decomposition, and
that use of the combination of sequestering agents makes it
unnecessa~y to incorporate a lithium salt in the developer in
order to prevent precipitate formationO
The primary aromatic amino color developing agents -
that can be utilized in the compositions and methods of this
invention are well known and wideIy used in a variety of color
photographic processesO They include aminophenols and
, ... .
5-
.. ~ . - . , , " . .- . , .. ,. :, :: ~
~55~7~:i3
p-phenylenediamines. They are usually used in the salt form,
such as the hydrochloride or sul~ate, as the salt ~orm is
more stable than the ~ree amine, and are generall.y empl.oyed
in concentrations o~ from about 0.1 to about 20 grams per
liter of developing solution and more pre~erably from about
0.5 to about 10 grams per liter o~ developing solution~
Examples of aminophenol developing agents include o-
aminophenol, p-aminophenol3 5-amino-2-hydroxy-toluene, 2-amino-
3-hydroxy-toluene, 2-hydroxy-3-amino-1,4-dimethyl-ben~ene, and
the like.
Particularly useful primary aromatic amino color
developing agents are the p-phenylenediamines and especially
the N,N-dialkyl-p-phenylenediamines in which the alkyl groups
or the aromatic nucleus can be substituted or unsubstituted~
Examples of use~ul p-phenylenediamine color developing agents
include N,N-diethyl-p-phenylenediamine monohydrochloride, 2-
amino-5-diethylaminotoluene monohydrochloride, 4-amino-N-ethyl-
N-~-methanesulfonamidoéthyl]-m-toluidine sesquisul~ate mono-
hydrate, 4-amino-3-methyl-N-ethyl-N-[~-hydroxyethyl]-aniline
sul~ate, 4-amino-3-(~-methylsulfonamidoethyl)-N,N-diethyl-
aniline hydrochloride, 4-amino-N,N-diethyl-3-(N'-methyl-~-
methylsulfonamido)-aniline hydrochloride and similar color
developing agents disclosed in U.S. Patent Nos. 2g552g241 and
2,566,271. An especially pre~erred class of p-phènylenediamine
developing agents are those containing at least one alkyl
sul~onamidoalkyl substituent attached to the aromatic nucleus
or to an amino nitrogen. Other especially preferred classes
o~ p-phenylenediamines are the 3-alkyl-N-alkyl-N-alkoxyalkyl-
p-phenylenediamines and the 3-alkoxy-N-alkyl-N-alkoxyalkyl-p-
phenylenediemlnes. These develop ne agents are described in
5~763
United States patents 3,656,950 and 3,658,525 and can berepresented by the formula:
CH3 - CH2 _ ~ (CH2)n
~1 .
NH2
where n is an integer having a value of from 2 to 4~ R is
alkyl of from l to 4 carbon atoms, and Rl is alkyl of ~rom l
to 4 carbon atoms or alkoxy of from l to 4 carbon atoms.
Illustrative examples of these developing agents include the
following compounds:
N-ethyl-N-methoxyethyl-3-methyl-p-phenylenediamine
N-ethyl-N-methoxybutyl-3-methyl-p-phenylenediamine
~-ethyl-N-ethoxyethyl-3-methyl-p-phenylenediamine
N-ethyl-N-methoxyethyl-3-n-propyl-p-phen~lenediamine
N-ethyl-N-methoxyethyl-3-methoxy-p-phenylenediamine
N-ethyl-N-butoxyethyl-3-methyl-p-phenylenediamine
and the like.
In addition to the primary aromatic amino color
developing agent, the developer compositions of this invention
contain a salt of hydroxylamine. Such salts are typically
acid addition salts such as hydroxylamine sulfate3 hydroxylamine
hydrochloride, hydroxylamine phosphate, and the li~e.
As described hereinabove, the novel color developer
compositions of this invention contain the sequestering agent
1,3-diamino-2-propanol tetraacetic acid. In its commercially
available forms, this sequestering agent is often present in
admixture with minor amounts of nitrilotriacetic acid, for
example ten to twenty percent by weight of nitrilotriacetic
acid. Such mixtures of a major amount of 1,3-diamino~2-propanol
: '
--7--
.... . . . .... . .. . . . . .. .. .. ..... .. .. .. .... . . .. ..
~57~i3
tetraacetic acid and a minor amo~t of nitrilotriacetic acid
can be employed with satisfactory results in the developer
compositions of this inventionO
In addition to the 1~3-diamino-2-propanol tetraacetic
acid, the developer compositions o~ this invention also contain
a diphosphonic acid sequestering agent. Mixtures of two or
more diphosphonic acid sequestering agents can be used if desired.
The hydroxyalkylidene diphosphonic acid sequestering agents are
especially useful for the purposes of this invention3 particularly
those of the formula:
P03H2
R - C - OH
3 2
in which R is alkyl of one to five carbon atoms, such as methyl,
ethyl, n-propyl, isopropyl, n-butyl, n-pentyl, and the like.
Other useful diphosphonic acid sequestering agents include the
aminodiphosphonic acid sequestering agents of the formula:
P3H2
R - C - NH2
3 2
in which R3 is alkyl of one to five carbon atoms. Typical
examples of the hydroxyalkylidene diphosphonic acids are 1-
hydroxyethylidene-l~l-diphosphonic acid and l-hydroxypropyli-
dene-l, l-diphosphonic acid while typical examples of the
aminodiphosphonic acids are l-aminoethane-l,l-diphosphonic acid
and l-aminopropane-l,l-diphosphonic acid
The developer compositions of this invention contain
an effective amount of both the 1~3-diamino-2-propanol tetra~
acetic acid and the diphosphonic acid sequestering agent~
Typically the 1,3-diamino-2-propanol tetraacetic acid will be
--8--
7~3
used in larger amounts, on a molar basis, than the diphosphonic
acid sequestering agent since the essential function of the
1,3-diamino-2-propanol tetraacetic acid will be to sequester
calcium while the essential func-tion of the diphosphonic acid
sequestering agent will be to sequester iron and the iron will
typically be present in smaller amounts than the calcium. How-
ever3 the particular amount of each sequestering agent which is
optimum will depend upon the particular de~eloper composition
involved, and the metal ions ~rhich are present therein, and in
particular instances either one of the two sequestering agents
can be used in higher concentration than the other. Generally
speaking, the developer solution will contain from about 0.0002
to about 0.05 moles of 1,3-diamino-2-propanol tetraacetic acid
per liter of solution3 more typically from about OD 001 to about
0.02 moles per liter, and preferably from about 0~005 to about
0.01 moles per liter. It will also contain from about 0.0001
to about OoOl moles of diphosphonic aeid sequestering agent
per liter of solution, more typically from about 000002 to about
0.004 moles per liter, and preferably from about 0.0005 to about
0.001 moles per liter.
A preferred combination of sequestering agents for
the purpose of this invention is a eombination of l,3~diamino-
2-propanol tetraacetic acid which has the formula:
HOOC - CH2~ ~ CH2 - COOH
~ N-CH2 CH - CH - N
HOOC - CH2~ OH 2 ` CH2 - COOH
and l-hydroxyethylidene-l,l-diphosphonic acid which has bhe
for~ula:
P03H2
CH3 - C - OH
P3H2
_ 9_ . ,
' : .
~5~6~ :
In addition to the primary aromatic amino color
developing agent, the hydroxylamine salt, the 1,3-diamino-2-
propanol tetraacetic acid and the diphosphonic acid sequester-
ing agent, the developer compositions of this invention can also
contain any of the various components that are ordinarily
incorporated in color developing solutions, for example, mater-
ials such as alkalies, alkali metal sulfites, alkali metal bi-
sulfites, alkali metal thiocyanates, alkali metal bromides,
alkali metal iodides, benzyl alcohol, thickening agents, water
softening agents, and so forth. The pH of the developing solution
is ordinarily above 7 and most typically about 10 to about 130
Development of photographic elements in the color
developing compositions of this invention can be advantageously
employed in the processing of photographic elements designed
for reversal color processing or in the processing of negative
color elements or color print materials. The developer compo-
sitions can be employed with photographic elements which are
processed in color developers containing couplers or with
photographic elements which contain the coupler in khe silver
halide emulsion layers or in layers contiguous thereto. The
photosensitive layers present in the photographic elements
processed according to the method of this invention can contain
any of the conventional silver halides as the photosensitive
material, for example, silver chloride, silver bromide, silver
bromoiodide, silver chlorobromide3 silver chloroiodide, silver
chlorobromoiodide, and mixtures thereof. These layers can
contain conventional addenda and be coated on any of the photo- ;
graphic supports, such as, for example, cellulose nitrate
film, cellulose acetate film, polyvinyl acetal film, poly~
carbonate film, polystyrene film, polyethylene terephthalate
-10-
. .
~5~ 3
film, paper, polymer-coated paper, and the like.
The invention is further illustrated by the following
examples of its practice.
EXAMPLE 1
A photographic color developer was prepared with
the following composition:
Benzyl alcohol - 14.5 milliliters
Hydroxylamine sulfate - 3.4 grams
* Color developing agent - 4.3 grams
Potassium sulfite - 3OC7 grams
Potassium bromide - 0O34 grams
Potassium carbonate - 31.0 grams
Lithium sulfate - 1.78 grams
Water to make one liter
15 * 4-Amino-N-ethyl-N-(~-methanesulfonamido-ethyl)-m-toluidine
sesquisulfate monohydrate
Sequestering agents were incorporated in samples of
this developer composition as described in Table I below and
ferrous chloride was added to certain of the sampl.es in an
amount sufficient to give a concentration of ~errous ion as
indicated in Table Io A portion of each sample was stored in a
1000-milliliter graduated cylinder open to the atmosphere and
analyzed periodically for ammonia generation over a period of
two months. For. certain of the samples a second portion was
stored in a closed bottle and analyzed periodically for ammonia .
generation over a period of two monthsO
.,
-11- ,: ~.'
557~i3
_
o V
o o ~
'' ~ e
~o~a ooooooooooo~oooooooo~ . ~
. ~D
. - .
h . o "
v ~ h
m~ O~O~OOoOOOOOO~OOOOOO~OO~o
- ~ ~ N ~ ~ ~ ~ N N N
R m
_ .
h - ~1 0 ~t-- O N
h~ OOOOOOOOOOOOOOO OOOON~OOONOO ~ ~
V R ~ ~ 2
~ _ . h N m
C ~ h . rt
O h~ ~o~OOOOOO OOOOOO~OOOOQO~OOO ~ , ~t`
O _ N N ~ a rt O rt N ~ ~ ~ U V
O O ~ h
~ g~
. t h ~t h
h rt rt rt rt ~ ~ ~ ~ ~ ~ rt O O O O O' ~ O O rt O O ~ ~ ~ ~ O ~ ~ N
t O O O O O O O O O O O O rt O ~i O O O ~ ~ ~ O
- h h ,1 rt
~C~ V ~
. ~ ~ ~ Z rt H
2~ 0
Z rt ~ ~ ~ ~0 ~ 0 '; ~t ~ ~ ,~t r~ r0t rt N N & ~ N ~ ~ ~ N
-12 -
__
7~3
~ V o N ~
~ ~ C.J N ~ O I I I I ~ I
CO ,~
~-1 0 ~ U N N N
0
O ~) N I N I C~
~ 0 q-l o~
y~ S ~ l
D I N C~
c o . ~1 , 5 ,! , ~ n ~ i~ t ~71 N) C,~ , , , ~ I i i
o~ ~ I N~ i t ii
0 ~ .
i.. c s~ v ~o~ ~ t ~ -t ~ i~ i~) ~77 i~ C~J ~I C~ i ~3 i
~g~ H¦~ ~1,,,,o~,,,,I,I~,,II,,-,
c ~ ~ ~ :-
ld t i~ ~ ¦ ~t N t i iN t~ J t N N i-rt ~ ~J N O
3 ~c 1 . o . I , $
o~ ~ ~ ,~1
.. ....
--~ -I ¦ trl N ~ t l~O N t ~ i~ N i'7) N N i., ,It O ,--~ ~ N
o .C ~D ~1 ~ t ~j; ~ ~ N t N ir~ N ~ i'rt i'n 1~ i O ~ ;
':!CC i_ r~ N~ i i ii i I ~ ii i i i i ~I t
C~ ~ l ~ i t ~ ~ "r) tl-t C~7 N in ~ -1 t
~ ~¦ ~
¦ t i. CO O i.-- ~ CO ~O O CO a~ ~D N ~ i7') N t ~
i~0 Z ¦ ~I N t~ t 1~ ~D i, ~0 0~ O .-1 ~ ~ t ~ ~O ~ CO a~ O 1 ;
'
.
- ~1 .
r~l l , l I I I '
L~
~1
~1
D¦IIIIII ~
~ l l l l l l
r)l '
D¦
~ Y~l I I I I I 1` '
E~
o o
~ ~ -~ o o J
~1,, , -.
~ D
D l
11111l
- ~1 1 1 1 1 , , . .
, , , , , ,
. I I I I ~ I
~1 ' ` .
l l l l l l
C~
. ,-`.
1 ~ 1 11 1 ,.
ol ~ o ~ J
CQ O
a) z C~
N C~ N CU C~
- 1~55763
5S~
Results of the tests for ammonia generation in the
closed samples are given in Table III below, in which the
values reported represent the concentration of ammonia in the
developer solution measured in milligrams per liter at the
specified number of days from the s-tart of the test~
TABLE III
Days From Start of Test
Test
~o. 0 14 28 53 55 56 57
1 14 4 4 -- -- -- 3
2 7 1 3 __ ~
3 28 184 219 -- -- ~~ 37
4 20 185 244 -- -- -- 288.
7 3 4 -- -- -- 4
15 6 5 2 4 -- __ __ __ :
7 8 7 16 __ 17 __
8 6 5 12 -- -- 18 --
9 10 3 6 -- __ 4 __
8 2 7 -- -- 3 --
2011 9 3 29 -- -- 10 --
12 6 3 10 -- -- 8 --
13 2 5 27 -- __ 8 --
14 3 13 26 __ 65 -- __
3 14 26 -- 49 __
2516 2 15 20 44 -_ __ __
17 4 30 5 143 -- -- ~~ : -~
18 3 16 35 58 -- __ _
: 19 3 3 -- 6 -- -~
As shown by the data in Tables I, II and III3
when both the sequestering agent 1,3-diamino-2-propanol tetra-
acetic acid and the sequestering agent l-hydroxyethylidene 1,
l-diphosphonic acid are added to the color developing solution
in e~fective amounts the e~olution of ammonia is suppressed
whether or not iron is present in the solut,ionO For example,
-15-
~5~3
,
~ests 73 8~ 11, 12~ 26 and 27 descri.be developer solutions
containing iron, 1~3-diamino-2-propanol tetraacetic acid and
l-hydroxyethylidene~ diphosphon:ic acid and these under~
went formation of ammonia to only a very limited extentO In
tests 3 and 4 there is an insufficient amount of l-hydroxy-
ethylidene-l, l-diphosphonic acid for the amount of iron
present so extensive ammonia generat;ion took placeO The
data of Tables I3 II and III also show that the sequestering
agent l-hydroxyethylidene-l, l-diphosphonic acid by itself
is effective in preventing the generation of ammonia in a
developer composition containing iron if used in a suffici.ent
amount. This is shown by test number 220 However3 use of
this sequestering agent by itself in amounts sufficient to
prevent the ammonia generation results in the formation of
1~ an undesirable precipitate in the developer solution, unless
lithium ions are incorporated in the solution in a sufficient;
amount to prevent such precipitate formation~ This is shown
by tests in which a developer composition as described herei.n~
above was prepared, the concentrations of sodium, lithium
and calcium ions were varied as indicated, the solutions were
- stored in covered l-liter beakers3 and the solutions were
analyzed periodically for the presence of a precipitate of
l-hydroxyethylidene-13 l-diphosphonic acid. The results are
reported in Table IV.
~16-
i~l35~ 3
0 C~
~ 0
,, ., ,, ,,_
C C o C
V ~ ~ ~ ~
5 ~ C 5 5 C 5 C
O O 0 0 0 ~ O ~
V ~ ~, V 6~ V
0 ~ ~ ~ 0 5~ a ~
V~V .~V'.l==_======-===_===
R ~ 0 ~1, D. O Q~ 0
~rl .r~ h ~rl ~I h ~I h
O O D. O O 1~. 0 t~-
h ~ ~ ~ ~ ~ C = = = -- = = = = = = = -- = = = = =
C . ~
V H O C O O O O ol' OJ ~ O O ~t C~.l O ~ CU O
oo oo oo oo oo oo oo oo-
O
. ' '
~0
.~ ~` .
~ ~a H O C ~I ~ 10 0 0 0 0 0 ~ 1 ~1 0 0 0 0 0 0 r-l r l ~1 0 0 0
D~ S 0 O O O O O O O' O' O' O' O' O 0 0 0 O' O' O' O O' O 0 0 0 .
~ .. `~
0
HO ~ ~L ~ ~0 0 ~0 ~ ~ ~ O O O 0 0 O 0 0 0 O 0
O
C~
' ~ V _
c~ ~ ~ h ' , -
~ ~ ~ ~ O O O O O O O O O U~ ~ O O o o o o
0 ~1 C~i N N N N N N N CU N . N N CU I U N
C Cll`~
O~
O
C
s: c 5J . ! . . ! c . . . . . . .
OC 3~ 1 ~ I rl ~ ~ i ~ O O O O O O C~ O 0-0 0 O O O O
.~ n 8 . . .
1 7
.. .
~ '
.. , , . . ~. , .
:~55~7~ii3
3 3
O O = = U~ ~ ~ U~ = ~ U~ = = = = = = . = = = = = = =
C~ V ~
==.1VV.~=V_~===.=========-=
~ O O ~
O ~ R. O O R- O ~.
G ~: - ~ S~ = = = = = = = = = - = =
O H V~ N O t C~l O t N O t o O ~ C~J O ~ N O N O t O
OOOO OO OO OO OO OO OO
~ol
C _ ¦ O O ~ 1 ~1 0 0 0 0 0 0 ~1 ~1 _I ~0 0 ~ N N ~1
H ~ ~
~ ~ ' .
~ . ~
~ ~o ~ ~ o o o o o o o o o o o o o o o o o o o o o o o o
H F. ~ 'I 'i ~ N N N N ~;J N N NO ON N NO NO ON ON c~ o O o o o o
~0' 4_~ O O O O O O O O O O O O 1~ ~ O O O
h ~ W N OJ N N N N N N ~ N N N C~i
~0 . , .
' ' '
1`` ~
~8 : ~
- l & - :
~557~i~
U~ .
cB
o LS~ = = = = =
~r( ~
~ .~ .
o
~
a~
rl
æ ~
.,~
~ C)
rl 5-1
c~ P~
a>
S~ O
P~ ~ = = = = = .
.
O
rl
s~ æ
rl ~ ~ ~ ~N O ~ N O
,~ O r-l ~ O O O O
~1 0 ~ .. .
~ ~ O O
O
V
O
~ r
_ ~ ~: æ ~ ~ ~ ~ N C~.l C~l ~
O rl O r-l ~ O O O O O O r-1
C) ~ H O ,~ . . . . . ~ ` I
_ O ~ ~ O O O O O O
H V
m
E~ ~o
~
3 o o o o o o
o~ ~ o o o o o o
c~ H ~ ~ N N C'l N N N
~1 .a)--
æ c~
.
m
~ ~\ ~
U~
rl O O O O O O
u~ u~ ~ rl . ~ . . . .
a~ Q) i-~ N N N N N N
:~, ~ bD .
~ ~ . .
U~ U~
~0
~0 . '
¢~
.
æ
$~ ~^
5~ h ~rl
C) U~ rl ~
O r~ rl O O O O O O
v ~, !
a) ~;
U~~'
35~i7~3
As shown by the data in Table IV3 when a li.thium salt
is omitted from a developer solution containing l-hyd:roxy-
ethylidene-l, l-diphosphonic acid as the sole sequestering
agent, a precipitate is formed in most instances after a rel.atively
short period of storage, with the ti.me required being dependent
on such factors as the concentration of sodium and calcium ions
in the solutionD The formation of such a precipitate adversely
affects the performance of the developer solution so that it
is very desirable that the developer be capable of storage for
a relatively long period of time without precipitate formation.
Use of the combination of sequestering agents described herein
makes it possible to store the developer solution for long
periods without precipitate formation and without the need for
a lithium saltO
EXAMPL~ 2
A photographic color developer was prepared with the
following composition:
Benzyl alcohol 12 milliliters
* Color developing agent 5.5 grams
Potassium sulfite 301 grams
Potassium bromide 0O34 grams
Potassium carbonate 32 grams
Hydroxylamine sulfate 2~0 grams
Water to make one liter
"
25 ~ Di-p-toluenesulfonic acid salt of N-ethyl-N-methoxyethyl-3-
methyl-p-phenylenediamine
.
~20-
~. .
5~763
Sequestering agents were incor.porated in samples
of' this developer composition as described in Table V belowO
To certain of the samples lithium sulfate was added in the
amount indicated in Table V and to certain of the samples
ferrous chloride was added in an amount suf'ficient to give a
concen-tration of ferrous ion as indi.cated in Table VO One-
half of each sample was stored in a closed bottle while the
other half was stored in an open lOOO~milliliter graduated
cylinder. Both the open and closed samples were analy~ed
for ammonia generation over a period of two monthsO
-21-
~L~5576
_
o 0
~ O r~
O H . .
Q t~
:~
~: ~ o ~ o ~ ~ ~ ~ o ~ 5
o
~i C~ o
_ S: N
O ~ . :
~Q
O ~
~Q ~ N CO co ~ '
O O O O O ~i 0 ~i 'I tB '
.
_ ~ ~
i~ C N
$ o ' ~ :
~ C~ CO ~ 0 C ~ `~
~B ~ ~ ~ ~ ~ ~ ~. o
S~ ~ cq. ~ . . . ri ~`
~ bDN N N N N N O O ,~
O U~ bD '
. ~ 0 ~ ..
c ~ ~ ~ ~ o .~
~ ~ ~ co ~ ~ o
~-rl - ~ O ~ :,:
o a~ ~ o o o o o o o o ,D oo r~
a) 'I ~ o .~
S~ ~ ~ ., .
X qD . ' . ~:
O rl a)
~o ~ ~ . . -.- :
. :. :' .
o
Z r~ N(r) ~ L~~O ~ 0 r~i N
'~
~- .
~ I~' '
~55~7~i3
Results of the tests for ammonia generation in
the open samples are given in Table VI below, in which the
values reported represent the concentration of ammonia in the
developer solution measured in milligrams per liter at the
speci~ied number of days from the start of the test~
TABLE VI
Test Days From Start of Test
No. 0 3 7 14 _ 35 49
1 1712 8 9 12 12 10 8
2 445 78 110 102 95 56 47
3 25 3 3 5 3 5 3
4 68 6 6 7 8 6 l~
34 4 5 4 4 5 5
6 34 4 3 4 `4 -- 3
7 215 19 37 47 79 68 55
8 23 5 4 4 4 6 6
Results of the tests for ammonia generation in the
closed samples are given in Table VII below3 in which the
values reported represent the concentration of ammonia in
the developer solution measured in milligrams per liter at :~
the specified number of days from the start of the test~
TABLE VII
Test Dayl4From Sta35 of Tes4 ~ _
__ ,~. _.
1 9 12 35 35 33
2 96 126 152 140 112
3 4 4 8 6
4 10 10 17 13 9
6 4 7 8 10 :
3 6 6 5 9 9 9
7 22 35 103 114 107
8 4 4 9 10 9
-23-
- ~ ~
3~557~i3
The data in Tables V, v~r and VII show that when both
the sequestering agent 1~3-diamino-2-propanol tetraac.eti..c ac,i.d
and the sequestering agent l-hydroxyethylidene-1.3 l~diphosphon:ic
acid are added to the color developing solution in effective
amounts the evolution of ammonia is suppressed whether or not
iron is present in the solution, The data al.so show that it
is not necessary to include a lithium salt in a developer
containing both 1,3-diamino-2-propanol tetraacetic acid and
l-hydrox~Jethylidene-l, l-diphosphonic acid~
10The invention has been described in detail with
particular reference to preferred embodiments thereof3 but
it will be understood that variations and modifications can
be effected within the spirit and scope of the invention~ -
-24~
