Processing compositions for silver complex diffusion transfer process

Disclosed is a processing composition for silver complex diffusion transfer process which contains the following constituents (A) to (E) or (A) to (F): ______________________________________ (A) MOH (M is an alkali metal) 0.05-0.2 mole/l (B) an alkanolamine 0.25-0.7 mole/l (C) a sulfite 0.4-0.7 mole/l (D) a thiosulfate 0.03-0.08 mole/l (E) a p-dihydroxybenzene .gtoreq.0.07 mole/l (F) a benzotriazole 10.sup.-4 -10.sup.-2 mole/l, ______________________________________ the sum of (A) and (B) being 0.4 to 0.8 mole/l and the molar ratio of (B) to (A) being above 2.0. This composition can produce images and tone without scumming.

This invention relates to a processing composition used for silver complex 
diffusion transfer process and a method for carrying out silver complex 
diffusion transfer process using said processing composition. 
The principle of the silver complex diffusion transfer process (hereinafter 
referred to as DTR process) is well known through the description in U.S. 
Pat. No. 2,352,014 and many other patents and literature. In DTR process, 
the silver complex is transferred imagewise by diffusion from the silver 
halide emulsion layer to an image receptive layer and converted into a 
silver image in the presence of physical development nuclei in most cases. 
For this purpose, the imagewise exposed silver halide emulsion layer is 
previously disposed in contact or is brought into contact with an image 
receptive layer in the presence of a developing agent and a silver halide 
solvent to convert the unexposed silver halide into a soluble silver 
complex. In exposed areas of the silver halide emulsion layer, the silver 
halide is developed to silver which is insoluble and non-diffusible. In 
unexposed areas of the silver halide emulsion layer, the silver halide is 
converted into soluble silver complex which is then transferred to the 
image receptive layer and forms a silver image, generally in the presence 
of development nuclei. 
The DTR process is adaptable widely to the reproduction of documents, 
making of printing plate, making of block copy, and instant photography. 
Especially in the reproduction of documents or the making of a block copy, 
a negative element bearing a silver halide emulsion layer and a positive 
element bearing an image receptive layer containing physical development 
nuclei are brought into close contact in the DTR processing composition 
usually containing a silver complex forming agent to form a silver image 
in the image receptive layer of the positive element. The silver image 
thus formed is required to be pure black or bluish black in color and 
should be of sufficient density. It is important for the silver image that 
the contrast and sharpness are high and the image reproducibility is good. 
A high transfer speed is also desirable. Further, it is necessary that the 
quality of the positive element be not dependent to a great extent upon 
the processing conditions (such as, for example, time and temperature) and 
not deteriorate by running processing (i.e. continued use of the 
processing composition). 
In practice, the DTR process is generally carried out in a simple 
image-forming system. For instance, there is used a processor composed of 
a tray to hold a transfer-developing composition, squeeze rolls to bring a 
negative sheet and a positive sheet into close contact, and a motor to 
drive the squeeze rolls. Although various types have been designed and 
used in various countries of the world, the processors are generally 
operated at room temperature without temperature control except for 
special types, and are often different from one another in speed of 
conveyance and path length in a developer. From the principle of DTR 
process, it is easily understandable and also well known to the art that 
the process of image forming is affected to a great degree by the 
conditions of processing, particularly processing temperature and 
processing speed. 
As examples of general effects excerted by the change in processing 
conditions of DTR process, especially by the change in processing 
temperature and conditions of conveyance, mention may be made of the 
following: 
(1) Change in sensitivity, tone reproduction in gradation and color, and 
density (reflection and transmission densities). 
(2) Low temperature processing tends to promote the staining (caused by the 
formation of fine grain silver colloid) of the image receptive sheet. 
(3) An increase in processing temperature or a decrease in conveyance speed 
causes reduction in ability to reproduce micro images such as, for 
example, fine lines or fine spots. 
The background reasons for the long neglect of the above problems despite 
their importance seem to originate in the general belief that the DTR 
process is difficult to control because it is made up on the basis of 
delictate balance among chemical development, dissolution, diffusion, and 
physical development. 
Other practical problems of the DTR processing system originate in the 
circumstance such that each system has been commercialized in the form of 
a combination of negative element, positive element, and DTR processing 
composition; namely, the formulation and structure of the components have 
been developed so that the combination may meet to a certain degree the 
previously described quality requirements. There are used negative 
elements such as low sensitivity type for contact printing, high 
sensitivity type for camera work, and a type using a direct positive 
emulsion; positive elements such as a type utilizing reflection density 
and a type utilizing transmission density; and DTR processing compositions 
such as a type containing a developing agent and a type containing no 
developing agent. Combinations are made up from the negative and positive 
elements and processing compositions according to the method and mode of 
the particular use. Such a combination has a disadvantage in that if any 
one component of a combination of positive and negative elements and a 
processing composition selected to provide the best quality is replaced by 
a component of another combination, the best quality is no longer 
attained. It is desirable, therefore, if it is possible to find a 
general-purpose processing composition capable of providing excellent 
results when combined with any negative element and any positive element. 
An object of this invention is to provide a processing composition and a 
method of processing to be used in the silver complex diffusion transfer 
process, which composition produces on the positive element a silver image 
excellent in density, contrast, resolution, and tone without accompanied 
scumming even if the negative and positive elements are varied in type and 
combination under varied processing conditions, even under running 
processing conditions. 
It has now been found that the above object is achieved by a processing 
composition for the silver complex diffusion transfer process, which is 
characterized by containing in one liter at least the following 
constituents (A) to (E) and, if necessary, (F), the sum of (A) and (B) 
being 0.4 to 0.8 mole and the molar ratio of (B) to (A) being above 2.0: 
______________________________________ 
(A) MOH (M is an alkali metal) 
0.05-0.2 mole 
(B) an alkanolamine 0.25-0.7 mole 
(C) a sulfite 0.4-0.7 mole 
(D) a thiosulfate 0.03-0.08 mole 
(E) a p-dihydroxybenzene 
.gtoreq.0.07 
mole 
(F) a benzotriazole 10.sup.-4 -10.sup.-2 
mole 
______________________________________ 
The alkali agents (A) include sodium hydroxide, potassium hydroxide, etc. 
The alkanolamines (B) include the compounds represented by the following 
general formula: 
##STR1## 
wherein X and X' represent each a hydrogen atom, hydroxyl group, or amino 
group, l and m represent each 0 or an integer of 1 or larger than 1, and n 
represents an integer of 1 or larger than 1. 
As individual compounds, mention may be made of ethanolamine, 
diethanolamine, triethanolamine, diisopropanolamine, N-methylethanolamine, 
N-aminoethylethanolamine, and N,N-diethylethanolamine etc., especially 
preferred are secondary or tertiary alkanolamines. 
The sulfites (C) include sodium sulfite, sodium hydrogensulfite, etc. 
The thiosulfates (D) include sodium thiosulfate, potassium thiosulfate, 
etc. 
The p-dihydroxybenzenes (E) include hydroquinone, chlorohydroquinones, 
methylhydroquinones, etc. 
The benzotriazoles (F) include the compounds represented by the following 
general formula: 
##STR2## 
wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 represent each a hydrogen 
atom, alkyl group, alkoxy group, halogen atom, acylamide group, 
sulfonamide group, cyano group, sulfo group, carboxyl group, 
alkoxycarbonyl group, aryl group, nitro group, aminocarbonyl group, or 
##STR3## 
group, where R and R' represent each a hydrogen atom or alkyl group. 
As individual compounds, mention may be made of the following: 
(1) Benzotriazole 
(2) 5-Methylbenzotriazole 
(3) 5,6-Dimethylbenzotriazole 
(4) 5-Phenylbenzotriazole 
(5) 5-Ethylbenzotriazole 
(6) 5-Methoxybenzotriazole 
(7) 5-Aminobenzotriazole 
(8) 5-Dimethylaminobenzotriazole 
(9) 5-Acetamidobenzotriazole 
(10) 5-Methanesulfonamidobenzotriazole 
(11) 5-Aminocarbonylbenzotriazole 
(12) 5-Methoxycarbonylbenzotriazole 
(13) 5-Carboxybenzotriazole 
(14) 5-Chlorobenzotriazole 
(15) 5-Bromobenzotriazole 
(16) 5-Nitrobenzotriazole 
(17) 4-Nitrobenzotriazole 
(18) 5-Cyanobenzotriazole 
(19) 5-Sulfobenzotriazole 
(20) 4-Aminobenzotraizole 
Although being well-known compounds, the constituents (A) to (F) have 
heretofore not been examined for the same purpose as that of the present 
invention. As a consequence, it has been only possible to obtain a 
defective processing composition as shown hereinafter. 
The constituents (A) and (B) constitute substantially the alkali component 
of the present processing composition. However, if necessary, other alkali 
chemicals such as sodium carbonate can be added unless the total 
alkalinity will not surpass the maximum alkalinity attainable with (A) and 
(B) under the conditions as specified above with respect to individual and 
total amounts and molar ratio. The pH is in the range of from about 10.0 
to about 12.5. 
The specified amount of the alkali agent (A) is smaller than that 
customarily used. Owing to the coexistence of an alkanolamine (B), if the 
alkali agent (A) is increased beyond 0.2 mole/liter (8 g/liter in terms of 
NaOH) in the case of high temperature development, e.g. at 30.degree. C., 
there will occur a decline in transmission density as well as in the 
ability of forming micro images, and, in the case of running processing, 
yellow staining of the white background of a positive element. A suitable 
amount of alkali agent (A) is in the range of from 0.1 to 0.2 mole/liter. 
The use of alkanolamines (B) in processing compositions for the DTR process 
is described, for example, in Japanese Patent Application "Kokai" 
(Laid-open) No. 93,338/73, in which are also shown various advantageous 
functions of alkanolamines. However, it is seen from Examples 1 and 2 of 
said Application that when a sulfite is used as a preservative, the 
transmission density becomes markedly decreased with the increase in the 
amount of alkanolamines. 
The present inventors carried out a large number of experiments and, as a 
result, it was found that the above difficulties are substantially 
overcome and the density decrease or the yellow staining is minimized 
under the conditions of running processing, by reducing the amount of an 
alkali agent (A), increasing the molar ratio of an alkanolamine (B) to 2.0 
or above for 1 mole of (A), and limiting the sum of (A) and (B) to 0.4 to 
0.8 mole/liter so that an excessive addition of (B) may be avoided, as 
described above. The molar ratio of an alkanolamine (B) to an alkali agent 
(A) is 2.0 or above, preferably 2.5 or above. The yellow stain formed on 
the white background, which is one of the disadvantages due to the use of 
an alkali agent (A) in abundance is considered to be originated from the 
colloidal silver as described in Japanese Patent Application "Kokai" 
(Laid-open) No. 116,536/83 for example. 
By using a sulfite (C) in an amount of 0.4 to 0.7 mole/liter, it was found 
that the density is improved and the yellow staining under the conditions 
of running processing is also avoided to a large extent. The developing 
agent hydroquinone is oxidized by the running processing to form a 
so-called sulfate salt by the addition of a sulfite to cause a decline in 
developing power, resulting in yellow staining. In order to maintain a 
sufficient developing power, a large amount of the sulfite is used 
depending on 0.07 mole/liter or more, preferably 0.08 mole/liter or more 
of the developing agent p-dihydroxybenzene (E). A preferable amount of the 
sulfite is 0.4 to 0.60 mole/liter. A preferable molar ratio of the sulfite 
(C) to the p-dihydroxybenzene (E) is in the range of from 3.5 to 5.5. 
The processing composition of this invention preferably contains 
1-phenyl-3-pyrazolidone or a derivative thereof in addition to a 
p-dihydroxybenzene (E). The object of this invention can also be achieved 
by the inclusion of 1-phenyl-3-pyrazolidone in negative or/and positive 
elements. A preferable amount of 1-phenyl-3-pyrazolidone is in the range 
of from 2.times.10.sup.-3 to 2.times.10.sup.-2 mole/liter. 
The thiosulfate (D) is also an important factor to achieve the object of 
this invention. Although depending upon the amounts of other constituents 
(A), (B), (C) and (E) or (F), the amount of a thiosulfate is generally in 
the range of from 0.03 to 0.08 mole/liter (from about 7 to 20 g/liter in 
terms of sodium thiosulfate pentahydrate), preferably from 0.04 to 0.07 
mole/liter (from about 10 to 17 g/liter in terms of sodium thiosulfate 
pentahydrate). 
The disadvantages caused by the presence of an excessive amount of a 
thiosulfate include a decline in transmission density or in 
reproducibility of micro images when the processing composition is used at 
high temperatures (28.degree. C. or above) or in a processor of low 
conveyance. 
It is possible to use a thiosulfate in combination with other silver halide 
solvents such as thiocyanate salts. 
The benzotriazoles (F) are known as antifoggant. It is described in 
Japanese Patent Application "Kokai" (Laid-open) No. 79,445/80 that the 
density decline accompanying the high speed processing is prevented by the 
potassium ion concentration and the antifogging action of a bromide. 
However, the bromide was found to have various disadvantages such as a 
large change in density with the change in processing temperature, a large 
degree of staining in the running processing, and a reddish tone of the 
silver image depending upon the type of negative element. 
It was found that in order to achieve effectively the object of this 
invention without adversely affecting the characteristics of a processing 
composition containing the constituents (A) to (E), it is important to use 
a benzotriazole as the antifoggant. As compared with equivalent moles of 
potassium bromide, benzotriazole acts as a better antifoggant, shows 
optical density maximum in the range of from 10.sup.-4 to 10.sup.-2 
mole/liter when the content is varied, is higher in optical density and 
lower in the dependency upon processing temperature. Moreover, 
benzotriazole produces less stain in the running processing, gives a 
desirable black silver image independent of the type of negative element, 
and improves the ability of micro image formation. Best results are 
obtained especially for a black silver image by using a benzotriazole in 
combination with mercapto compounds such as 1-phenyl-5-mercaptotetrazole, 
2-mercaptobenzoimidazole, and 2-mercapto-5-phenyl-1,3,4-thiadiazole, 
though these mercapto compounds do not give good results when used alone. 
The processing composition may contain, if necessary, inorganic 
antifoggants such as potassium bromide and potassium iodide. This 
invention does not exclude the joint use with these compounds. 
As described in the foregoing, the present processing composition is an 
autocome of the extensive research to find a general-purpose processing 
composition containing essential constituents (A) to (E) or (A) to (F), 
which composition produces a high quality image for any combination of 
materials. The present processing composition guarantees a silver image of 
highest quality for any negative element, positive element, and 
combination thereof without needing the change of the composition, 
indicating the usefulness of this invention. 
The processing composition of this invention preferably contains 
1-phenyl-3-pyrazolidone or a derivative thereof in addition to a 
p-dihydroxybenzene (E). The object of this invention can also be achieved 
by the inclusion of 1-phenyl-3-pyrazolidone in negative or/and positive 
elements. A preferable amount of 1-phenyl-3-pyrazolidone is in the range 
of from 2.times.10.sup.-3 to 2.times.10.sup.-2 mole/liter. A thiosulfate 
salt (D) is also an important factor to carry out favorably the DTR 
process. A preferable amount of thiosulfate is in the range of from 0.03 
to 0.08 mole/liter in view of transmission density, reflection dnesity, 
and tone. It is possible to use a thiosulfate in combination with other 
silver halide solvents such as thiocyanate salts. 
The processing composition preferably contains antifoggants. As examples of 
antifoggants, mention may be made of inorganic antifoggants such as 
potassium bromide and potassium iodide and organic antifoggants such as 
1-phenyl-5-mercaptotetrazole, 2-mercaptobenzoimidazole, 
2-mercapto-5-phenyl-1,3,4-thiadiazole, and imidazole derivatives. 
The amount of an antifoggant can be varied in relatively broad range. The 
optimum amount should be determined by taking into account the nature of 
the compound, that is, whether it is inorganic, such as potassium bromide, 
or organic, such as 1-phenyl-5-mercaptotetrazole. A suitable amount is 
generally in the range of from 1.times.10.sup.-4 to 1.times.10.sup.-1 
mole/liter. 
The processing composition of this invention may further contain thickners, 
e.g. carboxymethylcellulose and hydroxyethylcellulose; development 
modifiers, e.g. polyoxyalkylene compounds and quaternary ammonium salts; 
and water softeners, e.g. sodium hexametaphosphate and EDTA. 
The processing conditions for the present processing composition, such as 
time and temperature, vary depending upon various factors such as, for 
example, constituents of the photographic elements and constituents of the 
processing composition, though subject to no special restriction. 
The negative element generally used in DTR process carries on a support at 
least one silver halide emulsion layer containing 0.5 to 3.5 g/m.sup.2 of 
silver halide in terms of silver nitrate. Beside the silver halide 
emulsion layer, there are provided, if necessary, auxiliary layers such as 
subbing layer, interlayer, protective layer, and stripping layer. For 
instance, in order to ensure uniform transfer, the emulsion layer of the 
negative element can be provided with an overcoating layer of 
water-permissible binders as described in Japanese Patent Publication Nos. 
18,134/63 and 18,135/63, such as, for example, methylcellulsoe, sodium 
salt of carboxymethylcellulose, and sodium alginate. The overcoating layer 
should be sufficiently thin so as not to interfere with or retard the 
diffusion. The silver halide emulsion layer of a negative element and the 
image receptive layer of a positive element contain one or more 
hydrophilic colloidal substances such as, for example, gelatin or 
derivatives thereof, e.g. phthalated gelatin; cellulose derivatives, e.g. 
carboxymethylcellulose and hydroxymethylcellulose; dextrin, soluble 
starch, polyvinyl alcohol, and polystyrenesulfonic acid. 
The silver halide emulsion comprises hydrophilic colloids and, dispersed 
therein, silver halides such as, for example, silver chloride, silver 
bromide, silver chlorobromide, and these halides containing iodide. The 
silver halide emulsion may be sensitized in various ways during its 
manufacture or before coating. It can be chemically sensitized in a manner 
well known to the art with sodium thiosulfate, alkylthioureas, gold 
compounds, e.g. gold rhodanide and gold chloride, or a combination of 
these compounds. The emulsion is further sensitized generally for the 
region of from about 530 to about 560 nm, though can be panchromatically 
sensitized. A direct positive silver halide emulsion can also be used. 
The silver halide emulsion layer and/or the image receptive layer can 
contain any of the compounds generally used in carrying out the DTR 
process. Such compounds include antifoggants, e.g. tetrazaindene and 
mercaptotetrazole; coating aids, e.g. saponin and polyalkylene oxide; 
hardeners, e.g. formaldehyde and chrome alum; and plasticizers. A 
developing agent can also be included. The supports used in negative or 
positive elements are those which are customarily used, including paper, 
glass, film, e.g. cellulsoe acetate film, polyvinylacetal film, 
polystyrene film, or polyethylene terephthalate film; metal supports 
overlaid with paper; paper supports coated on one or both sides with an 
.alpha.-olefin polymer, e.g. polyethylene. The positive element can 
contain physical development nuclei, e.g. heavy metals or sulfides 
thereof. One or more layers of a positive element can contain those 
substances which play an important role in the formation of diffusion 
transfer images described in Brit. Patent No. 561, 875 and Belg. Pat. No. 
502,525, e.g. 1-phenyl-5-mercaptotetrazole. The positive element can also 
contain a fixing agent such as sodium thiosulfate in an amount of about 
0.1 to about 4 g/m.sup.2.

The invention is illustrated below in detail with reference to Examples, 
but the invention is not limited thereto. 
EXAMPLE 1 
Positive Element A 
This element was prepared in the following manner: On one side of a paper 
support, 110 g/m.sup.2 in basis weight, which had been coated on both 
sides with polyethylene, there was provided, at a coverage of 3 g/m.sup.2 
on dry basis, an image receptive layer comprising gelatin and a product 
made from polyvinyl alcohol and an ethylenemaleic anhydride copolymer, 
which contained palladium sulfide nuclei. 
Positive Element B 
This element was prepared in the following manner: On a polyethylene 
terephthalate film, there was provided, at a coverage of 3 g/m.sup.2, an 
image receptive layer of hardened gelatin containing palladium sulfide 
nuclei. 
Negative Element M 
This element was prepared in the following manner: On the same paper 
support as used in positive element A, there was provided a subbing layer 
containing carbon black to prevent halation and overlaid with an 
orthochromatically sensitized gelatino silver halide emulsion layer 
containing 2.0 g/m.sup.2 (in terms of silver nitrate) of silver 
chlorobromide (10% bromide), 0.3 .mu. in average grain size. 
Negative Element N 
A silver halide negative element N for the direct positive image was 
prepared by using the reference emulsion B described in Example 1 of 
Japanese Patent Application "Kokai" (Laid-open) No. 96,331/82 in place of 
the emulsion of the negative element M described above. 
The following processing compositions 1-11 were prepared as DTR processing 
compositions. 
The numerals in the table indicate mol per 1 l. 
__________________________________________________________________________ 
Unit: mole/liter 
1 2 3 4 5 6 7 8 9 10 
11 
__________________________________________________________________________ 
NaOH 0.15 
0.15 
0.15 
0.15 
0.025 
0.1 
0.25 
0.075 
0.15 
0.15 
0.15 
MAE.sup.1 
0.2 
0.4 
0.55 
0.7 
0.4 0.4 
0.4 
0.55 
0.4 
0.4 
0.4 
SS.sup.2 
0.5 
0.5 
0.5 
0.5 
0.5 0.5 
0.5 
0.5 0.35 
0.5 
0.5 
HP.sup.3 
0.06 
0.06 
0.06 
0.06 
0.06 
0.06 
0.06 
0.06 
0.06 
0.1 
0.02 
o . . . this 
-- o o -- -- o -- o -- -- -- 
invention 
__________________________________________________________________________ 
Note: 
.sup.1 MAE stands for N--methylethanolamine, 
.sup.2 SS for anhydrous sodium sulfite, and 
.sup.3 HP for sodium thiosulfate pentahydrate. 
Each processing composition contained, in common, 1 g of 
ethylenediaminetetraacetic acid, 12 g of hydroquinone, 1 g of 
1-phenyl-3-pyrazolidone, 50 mg of 1-phenyl-5-mercaptotetrazole, 50 mg of 
potassium iodide, 1.0 g of potassium bromide, and 3 g of 
hydroxyethylcellulose per liter. 
After imagewise exposure, negative elements M and N were coupled with 
positive elements A and B and processed in Dialine S-III processor 
(Trademark for a common DTR processor of Mitsubishi Paper Mills, Ltd.). 
After 60 seconds, each couple was peeled apart. 
Maximum densities (reflection density for positive element A and 
transmission density for positive element B) obtained when processed at 
20.degree. C. and 30.degree. C. were as shown in Table 1 and Table 2, 
respectively. 
TABLE 1 
__________________________________________________________________________ 
20.degree. C. 
Negative 
Positive 
element 
element 
1 2 3 4 5 6 7 8 9 10 11 
__________________________________________________________________________ 
M A 1.66 
1.66 
1.65 
1.60 
1.66 
1.68 
1.60 
1.65 
1.60 
1.70 
1.50 
M B 3.6 
4.4 
4.0 
3.6 
4.0 
4.6 
3.8 
4.0 
4.2 
3.8 
2.8 
N B 2.8 
3.6 
3.4 
3.3 
3.0 
3.8 
3.2 
3.2 
3.0 
3.4 
2.2 
__________________________________________________________________________ 
TABLE 2 
__________________________________________________________________________ 
30.degree. C. 
Negative 
Positive 
element 
element 
1 2 3 4 5 6 7 8 9 10 11 
__________________________________________________________________________ 
M A 1.64 
1.66 
1.63 
1.58 
1.66 
1.66 
1.58 
1.65 
1.55 
1.68 
1.55 
M B 3.8 
4.0 
3.6 
2.7 
4.0 
4.4 
3.0 
3.8 
4.0 
2.8 
3.0 
N B 3.0 
3.4 
3.0 
2.6 
3.4 
3.4 
2.8 
3.4 
3.0 
2.8 
2.5 
__________________________________________________________________________ 
After having been left standing for 3 and 7 days, each processing 
composition was used for processing 20 couples of negative and positive 
elements, each A-4 in size. The density of image areas and yellow staining 
in non-image areas of 20th positive element processed in the processing 
composition which had been left standing for 7 days were recorded 
according to the following criteria: 
o Entirely no staining. 
.DELTA. Local staining 
x Staining all over the element. 
The results were as shown in Table 3. 
TABLE 3 
__________________________________________________________________________ 
(20.degree. C.) 
Nega- 
Posi- 
tive 
tive 
ele- 
ele- 
ment 
ment 
1 2 3 4 5 6 7 8 9 10 11 
__________________________________________________________________________ 
M A 1.55 
x 1.65 
o 1.66 
o 1.55 
o 1.65 
.DELTA. 
1.62 
o 1.62 
.DELTA. 
1.62 
o 1.56 
x 1.65 
o 
1.60 
.DELTA. 
M B 2.8 
x 3.6 
o 3.8 
o 3.6 
o 3.0 
.DELTA. 
3.5 
o 3.0 
.DELTA. 
3.5 
o 2.2 x 
3.5 
o 
1.8 
.DELTA. 
N B 2.2 
x 3.0 
.DELTA. 
3.0 
o 2.8 
.DELTA. 
2.2 
.DELTA. 
2.8 
.DELTA. 
2.0 
x 2.8 
o 1.6 x 
3.0 
o 
1.2 
.DELTA. 
__________________________________________________________________________ 
From Tables 1, 2 and 3, it is seen that all of the processing compositions 
other than those of this invention, 2, 3, 6 and 8, showed one or other 
disadvantages, such as low density and yellow staining, which vary 
according to the type of elements, processing temperature, and running 
processing, indicating that such processing compositions are not to be 
called general-purpose compositions. 
The processing compositions of this invention, 2, 3, 6 and 8, gave best 
results independent of the processing conditions. The silver image formed 
were of high contrast and pure black in color. 
EXAMPLE 2 
Processing compositions were prepared according to the same formations as 
those of the processing compositions 1 to 11 in Example 1, except that the 
N-methylethanolamine was replaced by diethanolamine or 
N,N-diethylethanolamine. The processing compositions gave the results 
similar to those obtained in Example 1. 
EXAMPLE 3 
Positive element A, positive element B, negative element M and negative 
element N were prepared in the same manner as in Example 1. 
The negative elements M and N were each mounted in a common process camera, 
then imagewise exposed, and brought into close contact with the positive 
elements A and B, respectively, to effect the image transfer. 
The transfer processor was OSP-12 (Trademark for Mitsubishi Paper Mills, 
Limited) of the variable conveying speed type. The processing time was 
varied, while the time of transfer was set at 60 seconds. 
The original bore fine lines from 10 .mu. to 100 .mu. (at an interval of 10 
.mu. ). Exposure was controlled through an optical wedge of the reflection 
type. The micro image forming ability was evaluated by inspecting the fine 
line image formation. The original was photographed at 70% reduction. 
Evaluation of the tolerance of processing composition: 
The temperature of processing composition was varied in three stages of 16, 
23, and 30.degree. C. The retention time of negative elements in the 
processing composition was varied in three stages of 4, 6, and 9 seconds 
by varying the conveying speed. 
Evaluation by running processing: 
Sixty sets of the negative elements M and positive elements A, both A-4 in 
size, were processed in 2 liters of developer. The processing composition 
was then left standing for 10 days, while being exposed to the atmosphere. 
Then, various combinations of the negative and positive elements were 
subjected to transfer treatment and evaluated for the characteristics 
(transmission and reflection densities). The staining, color, and tone 
were visually evaluated. 
The composition of developer was as shown in Table 4. Processing 
compositions A and B were in accordance with the present invention. 
TABLE 4 
______________________________________ 
Composition of developer 
A B 
______________________________________ 
Sodium hydroxide (g) 4 " 
Sodium sulfite, anhydrous (g) 
60 " 
Sodium thiosulfate, 5H.sub.2 O (g) 
15 " 
Hydroquinone (g) 12 " 
1-Phenyl-3-pyrazolidone (g) 
1 " 
Potassium iodide (g) 0.05 " 
N--methylethanolamine (g) 
30 " 
Benzotriazole (g) 0.1 0.3 
Tetra-n-butylammonium bromide (g) 
2 " 
1-Phenyl-5-mercaptotetrazole (g) 
0.05 " 
Made up with water to 1 l " 
______________________________________ 
The results of processing were as summarized in Table 5. In this 
experiment, the conveying speed of the processor was set so that the 
retention time of the negative element in the processing composition may 
become 6 seconds. 
TABLE 5 
______________________________________ 
Results 
Item of Processing 
evaluation composition 
(Neg.) (Pos.) A B 
______________________________________ 
Transmission density 
16.degree. C. 
M B 4.2 4.0 
23.degree. C. 
M B 4.5 4.5 
30.degree. C. 
M B 4.2 4.3 
23.degree. C. 
N B 3.8 3.6 
Yellow staining of background of 
positive element 
16.degree. C. 
M A o o 
16.degree. C. 
N A o o 
Reflection density 
23.degree. C. 
M A 1.64 1.66 
Half tone color 
23.degree. C. 
M A Cold black 
Cold black 
23.degree. C. 
N A Warm black 
Warm black 
Relative sensitivity (%) to 
exposure in camera 
16.degree. C. 
M A 90 90 
23.degree. C. 
M A 100 100 
30.degree. C. 
M A 120 120 
Micro image forming ability (.mu.) 
16.degree. C. 
M A 24 22 
23.degree. C. 
M A 26 26 
30.degree. C. 
M A 30 28 
______________________________________ 
The processing compositions of the present invention, A and B, showed a 
high transmission density, sufficient stability against the change in 
processing temperature, no staining in the processing at low temperatures, 
desirable half tone color, reduced temperature dependency of the practical 
printing sensitivity (expressed in relative sensitivity, assuming the 
sensitivity in processing at 23.degree. C. to be 100), and excellent 
ability of forming micro images. 
In another experiment, it was confirmed that the processing compositions A 
and B according to this invention showed little yellow staining of the 
background under the conditions of high conveying speed at low 
temperatures, and very little decline in micro image forming ability under 
the conditions of low conveying speed at high temperatures. 
The results of evaluation of the transferred image obtained in running 
processing (exhausted composition) were as summarized in Table 6. 
TABLE 6 
______________________________________ 
Results of running processing (exhausted composition). 
Conveying speed: 6 seconds in retention time. 
Processing 
Item of composition 
evaluation 
(Neg.) (Pos.) A B 
______________________________________ 
Transmission density 
16.degree. C. 
M B 3.2 3.0 
16.degree. C. 
N B 2.8 2.8 
Yellow staining of background 
of positive element 
23.degree. C. 
M A o o 
23.degree. C. 
N A o o 
Half tone color 
23.degree. C. 
M A Cold black 
Cold black 
Gradation 
23.degree. C. 
M A Hard Hard 
______________________________________ 
The processing compositions of this invention were found to give good 
results in the running processing. 
EXAMPLE 4 
Using negative element M and positive elements A and B, a number of 
processing compositions shown in the following table were tested in a 
manner similar to that in Example 3. In the following table, there are 
also shown in generalized form the results obtained in high temperature 
processing (30.degree. C.; conveying speed corresponding to a retention 
time of 6 seconds; transmission density was used for the evaluation), low 
temperature processing (16.degree. C.; conveying speed corresponding to a 
retention time of 4 seconds; the yellow staining of the background was 
used for the evaluation), and running processing (the yellow staining of 
the background was used for the evaluation, as in Example 3). 
______________________________________ 
A C.sub.1 
C.sub.2 
C.sub.3 
C.sub.4 
______________________________________ 
Sodium hydroxide 4 12 4 4 4 
Sodium sulfite, anhydrous 
60 60 60 60 40 
Sodium thiosulfate, 5H.sub.2 O 
15 15 15 24 15 
Hydroquinone 12 12 12 12 12 
1-Phenyl-3-pyrazolidone 
1 1 1 1 1 
Potassium iodide 0.05 0.05 0.05 0.05 0.05 
Benzotriazole 0.1 0.1 0.1 0.1 0.1 
Tetra-n-butylammonium bromide 
2 2 2 2 2 
1-Phenyl-5-mercaptotetrazole 
0.05 0.05 0.05 0.05 0.05 
N--methylethanolamine 
30 30 15 30 30 
Made up with water to 
1 l " " " " 
Results: 
High temperature processing 
o x o x o 
(30.degree. C.) 
Low temperature processing 
o o x o x 
(16.degree. C.) 
Running processing 
o .DELTA. 
x o x 
______________________________________ 
All of the processing compositions, except for A of this invention, 
revealed one or other difficult problem. 
The present Example showed that the object of this invention can be 
achieved only with a processing composition of limited formulation. 
EXAMPLE 5 
Desirable results were obtained with a processing composition of the same 
formulation as that of A in Example 3, except that the 
N-methylaminoethanol was replaced by diethanolamine or 
N,N-diethylaminoethanol. 
EXAMPLE 6 
Desirable results were obtained with a processing composition of the same 
formulation as that of A in Example 3, except that the benzotriazole was 
replaced by 5-methylbenzotriazole or 5-chlorobenzotriazole.