DE1182525B - Diffusion photographic transfer process and image receiving layer therefor - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Boarding school Class: G 03 c

German class: 57 b -14/02

Number: 1182 525

File number: E 25966 IX a / 57 b

Filing date: December 6, 1963

Opening day: November 26, 1964

Diffusion transfer photographic process and BiWempf angsschicht for this

Applicant:

Eastman Kodak Company, Rochester, N.Y.

(V. St. A.)

Representative:

Dr.-Ing. W. Wolff, H. Bartels and Dipl.-Chem. Dr. J. Brandes, patent attorneys, Stuttgart 1, Lange Str. 51

Named as inventor:
Hans Max Wagner,
Wojciech Maria Przezdziecki, Wealdstone, Harrow, Middlesex (Great Britain)

Claimed priority:

Great Britain 7 December 1962 (46 201)

The invention relates to a photographic diffusion transfer process, which is particularly suitable for copying documents, as well as a non-light-sensitive material for implementation of the procedure.

The silver salt diffusion transfer process, occasionally also known as the solvent transfer process is known. In this procedure a photosensitive silver halide emulsion layer is imagewise exposed, usually through a document or the like, whereby a silver image is developed. During or after development becomes the emulsion layer in the presence of a silver halide solvent brought into contact with a non-photosensitive image-receiving layer which contains a layer in which a compound which form a visible silver image or an image of a visible silver compound is capable when brought into contact with a soluble silver complex. While When the two layers are in contact, the unexposed silver halide becomes the emulsion layer dissolved by the silver halide solvent, thereby forming a soluble silver complex, which diffuses into the non-photosensitive layer.

In the known diffusion transfer method

Ren are used to generate images from the diffuse 2

the silver complex development nuclei, which then

the development of the visible silver image can be accelerated, although the negative material nigen. These development nuclei usually consist of 30 containing enough silver halide to in principle produce the wisely from colloidal silver and colloidal silver- making six to eight copies of good density sulfide, but numerous other connections are also possible. One reason for this difficulty Fertilizing has been suggested for this purpose, which is obviously due to the fact that the positive is present some of these compounds only developed blue toning agents during the over-nuclei coming into contact with the negative by reaction with the soluble, in layer 35, where it diffused Form silver complex salt. Compounds limited by the solubility of the silver halide of this type are, for example, zinc sulphide and increased and the number of available copies is reduced, different colloidal metals, colloidal metal sulfates The invention is based on the object

and certain organic compounds. To develop a process and a material which,

The diffusion transfer methods known up to now do not have the disadvantages which have arisen up to now and enable the production of a single light-sensitive material which enables several copies of the exposed, positive copy in the image-receiving layer of the silver halide emulsion layer to be produced. It can also be made of excellent quality
known the transfer when using the first The task posed was through development

To interrupt the image-receiving layer and to use a photographic super-salt diffusion process Transfer using a second or even solved, in which an exposed silver superhalide third Continue receiving layer. Developed on this sion layer and the silver halide So far, two copies from an image-undeveloped area of the emulsion layer in Teten photosensitive material can be produced. Presence of silver halide solvent However, it has been found to be very difficult to diffuse onto a Büdem receiving layer with a To control transfer conditions in such a way that white silver precipitant is transferred and with more inventive For good copies from an exposed material, an image-receiving layer is used which

409 729/334

Contains development nuclei that are in situ in an aqueous Dispersion of China clay (China clay) have been produced.

The method of the invention makes it readily possible to produce a single exposed photosensitive Silver halide emulsion layer to produce six to twelve copies of excellent quality.

The material required to carry out the method of the invention thus consists of a

characterized in that the image-receiving layer contains development nuclei which are in situ in an aqueous dispersion of china clay.

When producing the image-receiving layer, it is expedient to proceed in such a way that the development cores precipitated in the absence of a water-soluble colloid but in a suspension of china clay

for example gelatin, added that clay and kernels can be made to adhere to a carrier. For example, clay-to-binder ratios from 15: 1 to about i: 1 can be applied. Beneficial results have been obtained with one material obtained, which per 0.0929 m contained about 0.1 to 100 mg of cores and 0.2 to 3.0 g of gelatin.

Image-receiving layers or image-receiving papers, which have a layer of development nuclei on

photographic image-receiving layer with an io, which is in situ in a dispersion of china clay Colloidal binders and development nuclei that have been generated can occasionally cause images

lead, which do not have the normally desired neutral tone. To prevent this from happening, will the transfer of the soluble silver complex from the unexposed areas of the exposed Layer on top of the image-receiving layer, preferably in the presence of a long-chain aliphatic amine or a salt of the amine, such as the acetate of an aliphatic amine with 14 to

will. After the precipitation, a colloidal 20-18 carbon atoms in the chain can be carried out. That Binder, such as gelatin, added aliphatic amine or a salt thereof will be required whereupon the mixture on a carrier, such as in the suspension of the development cores for example paper, is applied. introduced before the suspension for coating

Although it is preferable to use development cores from. A particularly advantageous aliphatic zinc sulfide can be used; the amine according to the invention is octadecylamine in the form of its, however, all other typical core image acetate. The amine is preferably used in a Konner or silver precipitating agent, which was previously used in a concentration of 5 to 30 mg / m - if it is present in the receiving layer in the context of solvent transfer systems, or in a concentration of, for example, colloidal silver 0.05 to 0.5 g / l when it is used in the or colloidal metal sulfides, metal selenides, silver developer solution. Proteinates, etc. These "seed compounds" include suitable amines are also those under the trade also known Carey Lea silver as well as colloidal sulfides and selenides of the metals of the groups
IB IIB, IVB and VIII of the Periodic Table of
Elements, e.g. B. zinc, cadmium, nickel etc. These 35
Particles preferably have a diameter
from about 25 to 2500 angstrom units on average.

According to the invention, a Chinese tone is preferably used
is used, which has at least one such pure 40 -bromoiodide emulsion of the developable type, degree of unity, as it is peculiar to quinatones, which are used for and the like to carry out the process of making art papers. Emulsions suitable for the invention also include China clay (China clay) is a type of kaolin which is known for those that have a silver halide carrier other than their high purity. Kaolin contains nor- gelatine, z. B. collodion, albumin, synmally a mixture of silicic acid and aluminum 45 thetic resins and the like. B. made of glass,

Cellulose nitrate, cellulose ester, paper or metal and the like.

The silver halide developing solution required to initiate the development of the exposed photosensitive Materials can be used, need not meet any special conditions. The developer solution can consist of a normal developer solution that is used to develop films normally used in photographic copiers or papers, with the exception papers are desired. however, that a silver halide solvent such as

The development nuclei are usually aided with sodium thiosulfate, sodium thiocyanate, or ammo produced a reaction in which fine ver- nia is present in such an amount that the divided, insoluble particles of the desired nuclei required formation of a soluble silver complex be precipitated. For example, sodium-60 is which difsulfide imagewise into the image-receiving layer be implemented with zinc nitrate, whereby zinc-based. Particularly suitable silver halide evolved sulfide arises. According to the invention, the release means that are used in to carry out the method precipitation of the cores, such as, for example, of cores from the invention suitable developer solutions ver-zinc sulfide, can be used in an aqueous suspension are, for example, hydraulic guides, which preferably contains 30 to 70% China clay ent- 65 quinone, monomethyl-p-aminophenol sulfate, amino. To the reaction mixture obtained, which contains the phenols, halogenated hydroquinones, toluenequinone, contains precipitated nuclei and the Chinese tone, then p-hydroxyphenyl, aminoacetic acid, 3-pyrazolidone at least as much colloidal binder as developing agent, such as l-phenyl-3-pyr-

name "armies" known amines from Armor Industrial Chemical Co. and those that are water soluble.

The silver halide emulsion can be any of the known gelatin-silver halide emulsions consist of the developable type, such as a gelatin-silver chloride, chlorobromide, -chloroiodide-, -chlorobromoiodide-, -bromide-,

make up about 13 ⁰ Zo organic components with a minimum of other components such as Eisenjodiden, titanium dioxide, calcium oxide, manganese dioxide, sodium oxide and potassium oxide.

Other clays, such as bentonite and so-called fuller's earth, have not turned out to be quite so as advantageous as China shade proved, since with these not quite the background whiteness can be achieved,

5 6

azolidone and mixtures of these developing agents. After the first layer was applied, a

ties. Particularly advantageous developers are coated over with a second layer, which consists of the following layers which are formed from a combination of 3-pyrazolidone silver components: halide developing agents with weak developing agents, such as ascorbic acid, and the for example in U.S. Patent 7 5o / _o j _ee saponin solution 2 cm ³

Fonts 2,685,515, 2,685,516, 2,688,548, 2,688,549,
2,691,589 and 2,751,300. This coating mass was 70 cm ³ / m ²

The usual additives can be applied as a second layer to the emulsions.

ingested, such as chemical and 10 The exposed photosensitive material was spectral sensitizers. then through together with the image receiving layer

According to a preferred embodiment of the one device which is carried out for the solvent invention, the image receiving layer is suitable in direct transfer processes and which brings the de-contact with the silver halide emulsion. Contained wrapper solution. The exposed material and However, other arrangements are also possible. For example, the image-receiving layer was 10 to 20 seconds, for example, a support on which a core layer was left in contact, on which the negative emulsion layer according to the invention has been applied, has been peeled off. The wet negative with a removable silver halide emulsion layer was then coated onto a second piece of one-on-one. After exposure and a paper support-sensitive image-receiving layer, the emulsion can be removed using a silver halo 20, with the leading edges slightly separated from the disruptive solvent which has separated a developer from each other and on which the sandwich is held, the emulsion can be removed by passing one through the developing device , positive copy remains in the core layer. After a contact time of 20 seconds, the core layer can also be peeled off as an overcoat. In this way, eight to twelve copies of material, such as titanium dioxide, pigmented of excellent quality with a brown tint, could be produced, so that the positive silver image is set against one. The negative should become visible during the whitening of the background, if the silver driving is not obscured, otherwise the anhalide, which is reduced from the reverse side by the number of copies available. Support has been exposed, developed and shown that the density of copies is consistently shaped even with a silver halide solvent and that they do not curl when developed in a developer. This core layer is dried, is also suitable to be used in place of other core layers, working in that the compound of Example 2 with the solvent transfer processes ₃₅
have become known. The procedure described in Example 1 was followed

The following examples are intended to repeat the procedure of with the exception that the cores are in a To illustrate the invention in more detail: Dispersion of clay in gelatin were precipitated.

In this way a similar number of

Example 1 40 copies can be made. These copies ever owned

but a density a little less than that

A photosensitive silver chloride emulsion density of the copies obtained in Example 1, and layer was related to the original to be copied, the copies also had a shade of brown that subjected to a reflex exposure. At the same time it was a little lower. was a photographic silver halide developing 45

solution prepared, to which 1 to 2 g / l crystalline example 3

Sodium thiosulfate were given.

Furthermore, an image-receiving layer was produced. The method described in Example 1 was used

represents by placing on a paper support such as repeated with the exception that the cores in the wipe a carrier out of a 90 g document gelatin solution before mixing in with the clay copying material, a layer of the following coating water were precipitated. There were five copies Mastic was applied, which is obtained in the following, which has a tan tone and a density described manner: possessed, which was slightly lower than the density of the

Copies obtained according to Example 2.

China tone 30 g 55

Distilled water 80 cm »Example 4

0.01 n-AgNO ₃ 20 cm ³ The procedure described in Example 1 was followed

0 01 n-Na "S 20 cm ³ using the same negative material as

'^ 60 same developer solution and the same process

10% gelatin 50 cm ³ repeated steps.

The image receiving layer was made in a similar manner

The mixture was homogenized, whereupon as described in Example 1, prepared with the

possibly wetting agents, dyes or other exceptions, however, that the coating material

Sets were added and whereupon the volume to 65 contained 2 g of octadecylamia acetate. After the first

cm ^{3 was} enlarged with distilled water. A second layer had been applied

The mixture was then applied in one layer at 40 to 45 ° C., as described in Example 1.

Layer thickness of 50 to 80 cm ³ / m ² piled up. Using this material, six could do up to

twelve copies of uniform density and neutral clay can be made.

Claims (5)

Patent claims: 1. Silver salt diffusion photographic process in which an exposed silver halide emulsion layer developed and the silver halide of the undeveloped areas of the emulsion layer transferred by diffusion to an image-receiving layer containing a silver precipitating agent is characterized in that an image-receiving layer is used, the development nuclei contains, which are produced in situ in an aqueous dispersion of china clay (china clay) have been. 2. Photographic silver salt diffusion process according to claim 1, characterized in that that the transfer of the silver halide to the image receiving layer in the presence of an aliphatic table amine with 14 to 18 carbon atoms or salts thereof. 3. Photographic silver salt diffusion process according to claim 2, characterized in that that a silver halide emulsion layer is used in which the amine or a salt of the Amine is located. 4. Photographic image-receiving layer with a colloidal binder and a silver precipitant for carrying out the method according to claims 1 to 3, characterized in that it contains development nuclei generated in situ in an aqueous dispersion of china clay are. 5. Photographic image receiving layer according to claim 4, characterized in that si © additionally contains an aliphatic amine having 14 to 18 carbon atoms or a salt of the amine. 409 729/334 11.64 © Bundesdruckerei Berlin