US3255007A

US3255007A - Diazotype reproduction materials

Info

Publication number: US3255007A
Application number: US266230A
Authority: US
Inventors: Kosar Jaromir
Original assignee: Keuffel and Esser Co
Current assignee: Keuffel and Esser Co
Priority date: 1963-03-19
Filing date: 1963-03-19
Publication date: 1966-06-07
Anticipated expiration: 1983-06-07
Also published as: GB1064975A; BE645321A; AT277751B; DE1447737A1; GB1064974A; US3199982A; NL6402881A

Description

June 7, 1966 J. KOSAR 3,255,007

DIAZOTYPE REPRODUCTION MATERIALS Filed March 19, 1963 FIG.I

HEAT-DEVELOPABLE TWO-COMPONENT PHOTOSENSITIVE EZTIRTT HEAT-DEVELOPABLE TWO-COMPONENT PHOTO- SENSITIVE DIAZOTYPE REPRODUCTION MATERIAL IO FIG.2

TWO-COMPONENT PHOTOSENSITIVE P ECO LAYER DIAZOTYPE LAYER 23 SUPPORT 2I HEAT-DEVELOPABLE TWO-COMPONENT PHOTOSENSITIVE DIAZOTYPE REPRODUCTION MATERIAL 2O DEVELOPING SHEET 3O EAT-DECOMPOSABLE AMIDE 32 SUPPORT 3| FIG.3

H EAT-DECOMPOSABLE AMIDE 3 2 SUPPORT 3 4 TWO-COMPONENT PH OTOSENSITIVE DIAZOTYPE LAYER 35 TWO-COMPONENT PHOTOSENSITIVE DIAZOTYPE REPRODUCTION MATERIAL 33 INVENTOR JAROMIR KOSAR BY 6% ATTORNEY United States Patent 3 255 007 DIAZOTYPE REPRonrJcTIoN MATERIALS Jaromir Kosar, Beechhurst, N.Y., assignor to Keuflfel & Esser Company, Hoboken, N.J., a corporation of New Jersey Filed Mar. 19, 1963, Ser. No. 266,230 13 Claims. (Cl. 96-49) The present invention relates to diazotype reproduction materials and to methods and means for their development, and refers more particularly to heat-developable diazotype reproduction materials and to methods and means for their development.

Diazotype reproduction materials are well known and have many advantages over other means of reproduction when considering the combined bases of quality and cost. However, they do possess some disadvantages which are inherent in the method of development.

Two methods of development are generally used: the semi-moist method and the dry method. In the semimoist method the exposed diazotype material is passed through a bath of coupler and squeezed dry. In the dry method, the exposed diazotype material is passed through a chamber of gaseous ammonia to effect development.

The semi-moist method of development suffers from the disadvantageous requirements of periodic replenishment of the developer supply, removal of exhausted developer, periodic cleaning of developer container, and deleterious effects of the liquid developer on the diazotype base which is usually paper. The dry method has the disadvantages of requiring equipment to supply, confine, and exhaust the noxious ammonia.

Other means for developing diazotype materials have been tried but were less practical than either the semimoist or dry methods.

Heat for example has been used to develop images on reproduction materials but they remained heat-sensitive and ultimately were unsatisfactory as copies.

In an attempt to eliminate the disadvantages of both the semi-moist and the dry developing systems, heatdevelopment of diazotype reproduction materials was tried. This was feasible because exposure of a diazotype reproduction material through a master to a source of actinic radiations decomposes the diazonium compound in the non-image areas. Consequently, these areas cannot develop and the diazotype reproduction material in effect is fixed or stabilized during exposure. The latent image could then be developed by some developing agent in the sensitized layer, in a separate layer, or in a separate support.

For example, Dieterle in U.S. Patent 2,228,562 relates to a developing sheet treated with a heat-decomposable ammonia compound. Placed in contact with an exposed diazotype reproduction material and heated, the developing sheet liberated ammonia vapors which developed the latent image. The ammonia compounds, however, had very poor shelf-life and consequently, their practical use was limited.

Barde in U.S. Patent 2,313,288 incorporated urea into a layer with a diazoic that formed its own coupler as a photolytic decomposition product. Heat decomposed the urea to liberate ammonia vapors which then neutralized the acid formed during coupling. Morrison in U.S. Patent 2,732,299, on the other hand, incorporated urea into a separate stratum on the diazotype reproduction material to serve as the source of heat-liberated ammonia.

Greig in U.S. Patent 2,691,587; Marron in U.S. Patent 2,774,669; and Benbrook in U.S. Patent 2,789,904 all relate to developing sheets containing either the coupler or the source of heat-liberated alkali.

Kendall et al. in British Patent 815,005 relates to multilayer diazotype reproduction material which comprised M 3,255,007 Ice Patented June 7, 1966 a support bearing a coupler layer, a fusible barrier layer, and a diazo layer.

Botkin in U.S. Patent 2,727,820 relates to an improvement in the production of photographic prints by the diazotype process wherein carboxamides were included in the photosensitive diazo layer to act as developing aids when the diazotype reproduction material was developed in a conventional ammonia developing machine.

The system of using developing sheets containing a source of heat-liberated alkali avoided the disadvantages of liquid developers and of gaseous ammonia, but it introduced the inconveninece of a two-sheet system. The developing sheet had to be placed in uniform contact with the exposed sensitized surface of the diazo-type reproduction material to form a two-ply assembly which was then heated to effect development. The developing sheet was then separated from the reproduction material and set aside.

The major advantage of a developing sheet was the isolation of a critical ingredient until needed.

Isolation of the critical ingredient of the system could also be accomplished by precoatings or multilayer coatings. This would overcome the objection to the twosheet system, but at the expense of increased cost and increased technical difiiculty.

The simplest system was to coat all ingredients onto one support from one solution in one layer in one operation. One requirement was that both the solution and the coated layer be stabilized to prevent premature coupling of the diazo compound and the coupler.

The present invention provides heat-developable twocomponent light-sensitive diazotype reproduction materials,'systems, and methods, which avoid the use of liquid developers and gaseous ammonia and which are stable against further development. The invention is adaptable to the developing sheet system, the precoat or multilayer system, and to the single layer coating system.

One object of the present invention is to provide a heat-developable diazotype reproduction material, system, and method which does nothave the disadvantages of prior art.

Another object is to provide a heat-developable diazotype reproduction material, system, and method which does not require the use of liquid developers or gaseous ammonia for development.

Another object is to provide a heat-developable diazotype reproduction material which is stable against further color development.

Another object is to provide a heat-developable diazotype reproduction material which is inexpensive and which gives good quality diazo reproductions.

Another object is to provide a heat-sensitive developing sheet for the thermal development of diazotype reproduction materials.

Another object is to provide a system which is adaptable to the two-sheet, the precoat, and the single layer systems of thermal development of diazotype reproduction materials. I

Other objects of the present invention will become apparent in the course of the following specification.

In the present invention, thermally decomposable sources of alkali are used as developing agents for the diazotype reproduction material. These sources of alkali are organic nitrogen compounds which may be classified as amides. Depending upon their chemical nature, they may be used in the sensitized layer, in a precoated layer, or in a separate developing sheet. Thus these amides can be used in at least three diazotype reproduction systems.

The amides of the present invention are decomposed at elevated temperatures when it is desired to release ammonia. This raises the alkalinity of the sensitized layer and allows coupling to occur and thus renders the latent image visible.

Some of the amides found to be suitable for .the present invention are those derived from monobasic staturated acids, monobasic unsaturated, acids, aromatic carboxylic acids, aromatic hydroxy acids, saturated dibasic acids, and aromatic dibasic acids. These amides have the general formula:

Ri-( 'i1TTR2 R3 Where R is hydrogen, alkyl, substituted alkyl, alkylene, substituted alkylene, amidated alkyl, aryl, substituted aryl, amidated aryl, a heterocyclic ring or a polymeric chain, and

Where R and R may be the same or different and represent hydrogen, alkyl, substituted alkyl, amidated alkyl, aryl, or substituted aryl.

Some sub-generic structural formulas are the following:

nH2...1 NH

Where n is 0, 1, 2, 3, 4, 5, 8, or 17 R CH CONH where R; is OC6H C H or CO-NI- I CH2=(|3OONH2 where R is H, or CH R5G0lTIOiH5 CsHs where R is H, or CH RC H CONH where R is H, CH N0 NH CONH or OH R CONH where R 8 is a heterocyclic five-membered or six-membered ring l (iJOJ where there is at least one amido group per monomer unit for this amidated polymeric chain. n is preferably approximately 560.

Amides are derived from carboxylic acids by replacing the OH group with an NH group or NR R group where R and R may be hydrogen, alkyl, or aryl. The amides are generally solids at room temperatures; the

lower molecular weight amides being readily soluble in Water, while the higher molecular weightamides are almost insoluble in water.

By heating in the presence of acids, the amides are hydrolyzed to carboxylic acids with consequent liberation of alkaline vapors. These alkaline vapors are utilized to develop the exposed diazotype reproduction material. The presence of acid is not required for operation of the invention. This is demonstrated by Example 17 and others.

Combinations of diazonium compounds and couplers that are suitable for the conventional d-ry developing diazotype reproduction materials can be employed in the present invention. Examples of the diazonium compounds are the zinc chloride and the boron trifluoride stabilized salts of p-dialkylamino benzene diazonium chlorides. These compounds are used in concentrations ranging from 1.5 to 10% of the sensitizing solution, and they can be used singly or in combinations.

Some suitable couplers are phenols and naphthols, such as phloroglucinol, resorcinol, alpha-naphthol, betanaphthol, and 2,3-dihydroxynaphthalene-6 sulfonic acid (sodium salt). These couplers may be used singly or in ombination to vary the color.

The coating solution and the senstized layer can also contain various other chemicals commonly used in the preparation of light-sensitive diazotype reproduction materials. These include stabilizing acids, anti-oxidants, hygroscopic agents, wetting agents, and image intensifiers.

Acids that can be used are tartaric acid, citric acid, acetic acid, trichloroacetic acid, and 1,3,6-naphthlenetrisulfonic acid or its sodium salt.

Thiourea and allyl isothiocyanate are commonly used anti-oxidants.

The sensitizing solution and sensitized layer may further contain hygroscopic agents such as glycerine, ethylene glycol, or the like; wetting agents such as saponin and lauryl sulfonates; and image intensifiers such as zinc chloride and nickel sulfate.

' The coating solution is applied in a conventional manner to a suitable support, the excess removed, and the coating dried. Suitable supports include not only those types of papers such as ordinary pulp paper, rag paper, and document paper, but also starch filled cloth, felt, saponified cellulose acetate film, transparent cellulosic material such as cellophane, and the like. In the drawings:

FIGURE 1 is a sectional view of a heat-developable two-component photosensitive diazotype reproduction material 10 of the present invention comprising a support 11 and a heat-developable two-component photosensitive diazo-type layer 12 coated on said support;

FIGURE 2 is a sectional View of a heat-developable two-component photosensitive diazotype reproduction material 20 of the present invention comprising a support 21, a precoat layer 22 coated on said support, and a two-component photosensitive diazotype layer- 23 coated over said precoat layer on said support; and

FIGURE 3 is a sectional view of a developingsheet 30 comprising a support 31 and a heat-decomposable amide 32 impregnated in support 31, in juxtaposition with a two-component photosensitive diazotype reproduction material 33 comprising a support 34 and a two-component photosensitive diazotype layer 35 coated on support 34.

One method of the present invention for the preparation of a heat-developable reproduction material is to first treat a support material with a solution of an amide. After drying, the same support is treated on the same side or on the opposite side with a sensitizing solution containing as major ingredients: a diazonium compound, a coupler, and where desired, a stabilizing acid. After drying, the sensitized support is ready for use. The sensitized support is exposed through a master to actinic radiations and is then developed by heat'in the range between the decomposition temperature of the amide and the scorching temperature of the support material. The heat-activated liberation of alkaline vapors then causes the image to develop.

The preparation and'use of a heat-developable twocomponent photosensitive diazotype reproduction material precoated with an amide of the present invention is illustrated in Example 1.

In another method of preparation of the present invention, the amide is incorporated with the photosensitive diazonium compound, a coupler, and where desired, a stabilizing acid in a sensitizing solution which is applied to a support and then dried. The sensitized support can then be exposed through a master to actinic radiations. After exposure, heat is applied to the sup port. The temperature is preferably in the range between the decomposition temperature of the amide and the scorching temperature of the support mate-rial. This method of preparation is illustrated in Example 2.

A developing sheet was prepared by impregnating a support with a solution of an amide in an appropriate solvent. The solvent was then removed by drying. The developing sheet was then used to develop an exposed two-component photosensitive diazotype reproduction material by making face-to-face contact with the exposed sensitized surface of the diazotype material and subjecting the assembly to heat in the range between the decomposition temperature of the amide and the scorching temperature of the diazotype support. Alkaline vapors were liberated to effect development of the latent image. The preparation and use of a developing sheet utilizing an amide of the present invention is illustrated in Example 3.

As an alternative procedure, the alkali-liberating agent may be incorporated into the pulp or raw material used to manufacture the support in suitable proportions to obtain the desired results.

The developing temperature range was determined by two factors: the first was the decomposition temperature of the thermally decomposable amide, and the second was the scorching temperature of the support. The decomposition temperature of the thermally decomposable amide is affected by the presence of other chemicals in the system. The presence of a good source of hydrogen ions favors decomposition by hydrolysis.

The following examples further illustrate the present invention and are not intended to restrict or limit the scope of the invention.

EXAMPLES Example 1.30 grams of acrylamide were dissolved in 150 milliliters of water and were coated onto a paper The coating was dried to produce a preooated and sensitized diazotype reproduction material. This was exposed through a master to actinic radiations and developed by subjecting the reproduction material to 150 C. for a few seconds. The heat liberated alkaline vapors from the amide and allowed the diazonium compound and the coupler to form a blue dye image corresponding to the master image.

No liquid developer or gaseous ammonia was required for development. In addition the developed reproduction material was stable against further dye formation under the influence of heat. This precoating system was particularly suitable for amides which were not watersoluble or which were not compatible with the chemicals in the sensitizing solution.

Example 2.-A sensitizing solution according to the following formula was prepared and coated on a conventional silica-sized diazotype paper support:

Water ml 4500 Acrylamide g 900 Tartaric acid g 15 Trichloroacetic acid g 150 Sodium salt of 1,3,6-naphthalene trisulfonic acid g 180 p-Dimethyl-amino' benzene diazonium chloride, zinc chloride salt g 120 Sodium salt of 2,3-dihydroxynaphthalene-6-sulfonic acid g 150 Thiourea g 210 Zinc chloride g 120 ing to the master image.

This system and method was preferred whenever the water solubility and the chemical compatibility of the amide with the other chemicals permitted incorporation into a single solution. Diazonium compounds other than "p-dimethylaimino benzene diazonium chloride can be used e.-g., p-diethylam-ino benzene diazonium chloride, and N-ethyl-N-(Z-hydroxyethyl)-p-amino benzene diazonium chloride were also used. Another coupler such as phloroglucinol was also used.

Example 3.20 grams of acrylamide were dissolved in ml. of ethyl alcohol. This solution was used to impregnate a porous paper support. After drying, a developing sheet for the heat-development of exposed two-component diazotype reproduction mate-rials was produced. On a separate paper support the sensitizing solution of Example 1 was applied and dried. This was ex- !posed through a master to actinic radiations and developed by making face-to-face contact with 'the' developing sheet and subjecting the whole assembly to C. for 5 seconds. A blue dye image corresponding to the master image was produced without benefit of liquid developer or gaseous ammonia. The print was stable against any further dye formation due to the application of heat.

This system was ideal for amides which were not compatible with the chemicals of the sensitizing solution since isolation was complete. In principle, this isolation can also be achieved by the multilayer system described in British Patent 815,005 and by microencapsulation of the developing agent or the coupler.

These first three examples demonstrate the fact that an amide can be used in three different systems as the source of alkali for the heat-development of diazotype reproduction materials.

Example 4 .--The following sensitizing solution was prepared and coated on a support. After the coating was dried, the sensitized support was exposed to actinic radiation through a master and developed by subjecting it to heat. The color of the image was blue.

Water ml 150 Sodium salt of 1,2,6-naphthalene trisulfonic acid g 6 Trichlor'oacetic acid g 5 p-Dimethylamino benzene diazonium chloride, zinc chloride salt g 4 Sodium salt of 2,3-dihydroxynaphthalene-6-sulfonic acid g 5 Thiourea g 7 Zinc chloride g Formamide g 10 Example 5.A coating of the following diazo sensitizing solution was applied to a paper support:

An absorbent sheet, was soaked with the following solution:

Ethyl alcohol ml 100 N,N-diiphenylforrnamide a g 10 Trichloroacetic acid g 5 After drying, the developing sheet was brought into uniform contact with the sensitized paper which had been exposed through a master to actinic radiations. The assembly of developing sheet and the diazo sensitized paper was then heated at 150 C. for seconds to produce a blue image on the diazo sensitized paper corresponding to the master image.

Example 6.The following sensitizing solution was coated on a support suitable for diazotype reproduction materials:

Water ml 150 Trisodium salt of 1,3,6-naphthalene trisulfonie acid g 6 p-Dimethylamino benzene diazonium chloride, zinc chloride salt g 4 Sodium salt of 2,3-dihydroxynaphthalene-6-sulfonic acid g 5 Thiourea g Zinc chloride g 4 Acetamide g 30 pH adjusted to 3.4 with trichloroacet'ic acid.

The sensitized support was then dried and exposed through a master to actinic radiation. Heat was used to develop the latent image as a blue dye image.

Example 7.-To improve storage life, trichloroacetic acid was added according to the following formula:

Water ml 150 Tartaric acid g .Trisodium salt of 1,3,6-naphthalene trisulfonic acid g 6 p-Dimethylamino benzene diazonium chloride, zinc chloride salt g 4 Acetamide g 30 Sodium salt of 2,3-dihydroxynaphthalene-6sulfonic acid g 5 Thiourea g 10 Zinc chloride g 4 Trichloroacetic acid g 5.

The pH of the solution was 1.3. Storage life was improved by the addition of trichloroacetic acid. Material stored at 115 F. and 47% relative humidity for three days still produced acceptable and satisfactory prints. Lesser amounts of trichloroactic acid reduced the storage life of the sensitized reproduction material.

Example 8.-The following sensitizing solution was prepared and coated on a support suitable for diazotype reproduction materials on a production run basis:

Water ml 4500 Tartaric acid g Trichloroacetic acid g 150 Trisodium salt of 1,3,6-naphthalene trisulfonic acid g 180 p-Dimethylamino benzene diazonium chloride, zinc chloride salt g 120 Acetamide g 900 Sodium salt of 2,3-dihydroxynaphthalene-6-sulfonic acid g 150 Thiourea g 210 Zinc chloride g 120 The coating speed was 16 yards per minute within air-bar pressure of 3 /2 oz. of water. The drying temperature was 180 F.

The sensitized and dried material was then exposed through a master to actinic radiation and developed by the application of heat. The developed image was blue in color and satisfactory in density.

Example 9.A support sheet was pre-coated with the following solution:

Water ml 150 Acetamide g After drying, the precoated support Was sensitized with the following sensitizing solution:

Water ml 150 Trisodium salt of 1,3,6-naphthalene trisulfonie acid g 6 Trichloroacetic acid g 5 p-Dimethylamino benzene diazonium chloride, zinc chloride salt g 4 Sodium salt of 2,3-dihydroxynaphthalene-6-sulfonic acid g 5 Thiourea g 7 Zinc chloride g 4 The pH of the sensitizing solution was 1.0 After drying, the sensitized sheet was exposed through a master to actinic radiations and developed by heating at 150 C. for 4 seconds. A blue image corresponding to the master image was obtained.

Example I0.An absorbent base sheet was soaked in a solution containing 10 grams of acetamide in 150 ml. of ethyl alcohol and then dried to remove the alcohol to produce a developing sheet.

A paper support was sensitized with the following solution:

Water ml 150 Trisodium salt of 1,3,6-naphthalene trisulfonic acid g 6 T richloroacetic acid g 5 p-Dimethylamino benzene diazonium chloride, zinc chloride salt g 4 Sodium salt of 2,3-dihydroxynaphthalene-fi-sulfonic acid g 5 Thiourea g 7 Zinc chloride g 4 After drying, the developing sheet and the exposed sensitized support were placed in contact and heated at 150 C. for a few seconds to produce a blue image corresponding to the master image.

Example 1 1.T he following solution was prepared and coated on an absorbent support to form a developing sheet: v

Ethyl alcohol Q ml.. 25 T-richloroacetic acid g 1 Phenoxyacetamide g 2.5

Heating this sheet in contact at 175 C. for 5 seconds with a printed but undeveloped diazotype paper such as that described in Example 10 produced a brown image.

Example 12.A developing sheet prepared by coating the following solution on an absorbent support when heated in cont-act with printed diazotype paper as described in Example 10 caused a blue image to be produced on the diazotype paper:

Ethyl alcohol cc Trichloroacetic acid g 3 N,N-Diphenylacetamide g 10 Contact time was 6 seconds at 170 C.

Example 13.-The following solution was prepared After printing through a master, the blue image was developed by heating for 5 seconds at C.

Example -14.-Propionamide was used in the following solution to prepare a developing sheet:

Water cc 100 Trichloroacetic acid g 2 Propionamide g 5 When used to develop a printed diazotype paper such as that described in Example 10, a blue image was obtained. Contact time was 5 seconds at 150 C.

Example 15.The following chemicals were substituted individually for the propionamide in Example 13 with the result that the developed images were substantially the same as for propionamide:

n-Valeramide iso-Valer-amide n-Butyramide iso-Butyramide Example 16.-Hexamide, nonanamide, and stearamide were used separately in the following solution formula to prepare developing sheets:

Ethyl alcohol cc 50 Trichloroacetic acid g 1.5 Amide g 5 When these developing sheets were used to develop printed diazotype sheets prepared as described in Example 10, blue images were obtained. Contact time was 5 seconds at 160 C.

Example 17.The sensitizing solution was prepared with acrylamide according to the following formula:

Water cc 100 p-Diethylamino benzene diazonium chloride, zinc chloride salt g 4 2,3-dihydroxynaphthalene 6 sulfonic acid, sodium salt g 5 Acrylamide g 50 This solution was coated on an absorbent support and dried. When heat-developed at 150 C. for 5 seconds a blue color was developed.

Example 18.Polyacrylamide of low molecular weight such as PAM 10 was used in the following sensitizing solution:

This solution was coated on an absorbent support and was dried. After printing with ultraviolet light through a master, the image was developed by heating the coated support at 150 C. for 5 seconds.

Example 19.-Polyacrylamide such as PAM 10 was used in the following solution to prepare a precoat solution:

Water cc 100 P-olyacrylamide PAM 1O g 50 Trichloroacetic acid g 10 This solution was coated on a support and dried. The precoated paper was then sensitized with a solution such as described in Example 1. Heat treatment after exposing the sensitized support through a master produced a blue dye image.

Example 20.-The same polyacrylamide solution as in Example 19 was used to coat an absorbent support to make a developing sheet. When used as in Example 3 to develop a diazotype paper by placing it in contact with the exposed diazotype paper and heating the assembly for a few seconds at 150 C., a blue image on the diazotype paper was developed.

Example 21.Hexamethylene-bis-acrylamide was used to prepare a solution according to the following formula:

Ethyl alcohol cc Hexamethylene-bis-acrylamide g 10 Trichloroacetic acid g 5 This solution was used to impregnate an absorbent support. After drying, this developing sheet was placed in contact with sensitized and exposed diazotype paper and heated at C. for 8 seconds. A blue image was formed.

Example 22.--Methacrylamide was used in place of the acrylamide of examples 2, and 17, with the same results.

Example 23.-Malonamide was used in the following sensitizing solution to coat a support which was then dried:

Water cc 150 Malonamide g 25 1,3,6-naphthalene trisulfonic acid, trisodium salt g 6 Tartaric acid g /2 Trichloroacetic acid g 5 p-Dimethylamino benzene diazonium chloride, zinc chloride salt g 4 2,3-dihydroxynaphthalene 6 sulfonic acid, sodium salt g 5 Thiourea g 7 Zinc chloride g 4 Development of a blue dye image after exposure was accomplished by heating at 180 C. for 4 seconds.

Example 24.Benzamide was used in the following solution to prepare a developing sheet:

Ethyl alcohol cc 100 Benzamide g 5 This solution was then used to impregnate an absorbent support. Heating the developing sheet while it was in contact with a diazotype paper prepared as in Example 5 resulted in development of a blue color on the diazotype sheet.

' Example 25.-The solution of Example 24 was used also as a precoat solution. It was coated on a support, dried, and then sensitized with the following solution on the same side:

Water cc 150 1,3,6-naphthalene trisulfonic acid, trisodium salt g- 6 Tartaric acid g /2 p-Dimethylamino benzene diazonium chloride, zin

chloride salt g.'. 4 2,3,-dihydroxynaphthalene-6-sulfonic acid, sodium salt g 5 Thiourea g 7 Zinc chloride g 4 After exposure through a master, a blue dye image was developed by heating the exposed sheet for 5 seconds at 150 C.

Example 26.p-Toluamide was used in the following solution to prepare a developing sheet:

Ethyl alcohol cc 50 p-Toluamide g 5 Trichloroacetic acid g 1.5

The developing sheet was used to develop diazotype paper prepared as in Example 5. A blue color was developed by heating the developing sheet in contact with the diazotype paper for a few second at C.

Example 27.p-Nit-robe'nzamide was used inthe following solution to prepare a developing sheet:

Ethyl alcohol cc 25 p-Nitrobenzamide g 2.5 Trichloroacetic acid g 1.0

11 1 This developing sheet was used to develop a red-brown dye color in the same manner as in Example 26.

Example 28.Anthranilamide Was used in the follow-' ing solution to prepare a develop-ing sheet:

Ethyl alcohol cc 100 Anthranilamide g 10 Trichloroacetic acid g This solution was coated on a support to make a developing sheet which then was used to develop a diazotype paper as described in Example 5 to produce a blue dye image.

Example 29 .Anthranilamide was also used in the following sensitizing solution:

exposed sensitized sheet at 160 C. for 6 seconds produced a blue dye image.

Example 30.Phthalamide was used to make a developing sheet by coating a support with the following solution:

Ethyl alcohol cc 100 Phthalamide g 5 Trichloroacetic acid g 2.5

Placing this developing sheet in contact with a printed diazotype paper and subjecting the assembly to heat at 175 C. for several seconds produced a blue image.

Example 31.Salicylamide was used in a developing sheet prepared by coating a support with the following solution:

Ethyl alcohol cc 100 Salicylamide g 5 The developing sheet was used to develop a blue dye image as in Examples 5 and 30.

Example 32.Salicylamide was also used in a precoat layer by coating a support with the following solution:

Ethyl alcohol cc 150 Salicylamide g 10 The precoated support was then sensitized as in Example 9. After exposure through a master to actinic radiations, a blue color was developed by heating ,the sensitized precoated support for 5 seconds at 150 C.

Example 33.-2-furamide was used in the following solution to coat a support to make a developing sheet:

Ethyl alcohol 'cc 50 Z-furamide g 5 Trichloroacetic acid g 1.5

This developing sheet was used at 175 C. for 4 seconds to develop printed diazotype paper as described in Example 5.

Example 34.-N-Methylacetamide was used to prepare a developing sheet by impregnating an absorbent support with the following solution:

Ethyl alcohol cc 25.0 N-methylacetamide g 2.5 Trichloroacetic acid g 1.0

After drying, this developing sheet was used to develop exposed diazotype paper prepared asin Example 5 by placing the two sheets in contact and heating them at 165 C. for 7 seconds to obtain a blue color.

12 Example 35.Example 34 was repeated with 2-phenylacetamide in place of N-methylacetamide. After following the same procedure, a blue green image was obtained. Example 36.Nicotinamide was used in the following solution to impregnate an absorbent support to make a developing sheet:

Water cc 50 Nicotinamide g 5 This sheet was then dried and used to develop an exposed diazotype paper by placing it in contact with the exposed diazotype paper and heating the assembly at C. for 6 seconds to obtain a colored image.

Example 37.-A support was precoated with the following solution:

Water cc 50 Nicotinamide a g- 5 Trichloroacetic acid g 2 After drying, the precoated support was sensitized with the following solution:

Water cc 150 Tartaric acid g /2 1,3,6-naphthalene trisulfonic acid, trisodium salt g 6 p-dimethylamino benzene diazonium chloride, zinc chloride salt g 4 2,3-dihydroxynaphthalene-6-sulfonic acid, sodium salt g 5 Thiourea g 7 Zinc chloride g 4 After drying, the sensitized support was exposed through a master to actinic radiations and then developed by heating at C. for 5 seconds. A blue-black image was obtained.

It is apparent that the described examples are capable of many modifications and variation within the scope of the present invention. All such modifications and variations are to be included within the scope of the present invention.

What is claimed is:

1. A process for making a diazo reproduction of an image, which comprises the steps of:

exposing a diazo sheet to imagewise actinic radiation,

said sheet comprising a support resistant to the scorching effects of heat at the conditions of development and a photosensitive diazonium compound, a coupler therefor, and a thermally decomposable alkali-liberating amide on said support, said amide having the general formula:

where R is a member selected from the group consisting of hydrogen, alkyl, alkylene, aryl, and amidated polymer having a molecular weight of about 40,000, and R and R are members selected from the group consisting of hydrogen, alkyl and aryl; and heating said exposed sheet at a temperature between the decomposition temperature of the amide and the scorching temperature of the support to liberate alkali and produce a dye image on the diazo sheet.

2. A process in accordance with claim 1 in which said amide is water soluble and is intimately admixed with said diazo layer.

3. A process in accordance with claim 2 in which said amide is acrylamide. I

4. A process in accordance with claim 2 in which said amide is acetamide.

5. A process in accordance with claim 2 in which said amide is polyacrylamide with a molecular weight of about 40,000. 1

6. A process in accordance with claim 2 in which said amide is malonamide.

7. A process in accordance with claim 2 in which said amide is anthranilamide.

8. A process in accordance with claim 1 in which said amide is coated on said support between said support and said diazo layer.

9. A process in accordance with claim 8 in which said amide is acrylamide.

10. A process in accordance with claim 8 in which said amide is acetamide.

11. A process in accordance with claim 8 in which said amide is polyacrylamide with a molecular Weight of about 40,000,

12. A process in accordance with claim 8 in which said amide is benzamide.

13. A process in accordance with claim 8 in which said amide is salicylamide.

References Cited by the Examiner UNITED STATES PATENTS 2,047,217 7/ 1936 McQueen et a1. 2,358,871 9/1944 Maxwell. 2,653,091 9/1953 Greig 9649 1 4 2,683,088 7/1954 Reynolds 117 154 X 2,687,958 8/1954 Neugebauer et a1. 9693 X 2,727,820 12/1955 Botkin et a1. 9649 2,732,299 1/ 1956 Morrison 9649 2,774,669 12/ 1956 Marron et a1. 9649 2,786,807 3/ 1957 Schwartz.

FOREIGN PATENTS 519,408 12/ 1955 Canada.

564,915 10/ 1958 Canada. 1,249,913 11/1960 France.

816,601 7/ 1961 Great Britain.

127,464 2/ 1950 Sweden.

OTHER REFERENCES Degering: Outline of Organic Nitrogen Compounds, 1950, University Lithoprinters, Upsilanti, Michigan, pp. 408-411. Kosar: Photographic Science & Engineering, vol. 5,

20 No. 4, July-August 1961, pages 239-243.

J. TRAVIS BROWN, Acting Primary Examiner.

NORMAN G. TORCHIN, Examiner.

Claims

1. A PROCESS FOR MAKING A DIAZO REPRODUCTION OF AN IMAGE, WHICH COMPRISES THE STEPS OF: EXPOSING A DIAZO SHEET TO IMAGEWISE ACTINNIC RADITION, SAID SHEET COMPRISING A SUPPORT RESISTANT TO THE SCORCHING EFFECTS OF HEAT AT THE CONDITONS OF DEVELOPMENT AND A PHOTOSENSITIVE DIAZONIUM COMPOUND, A COUPLER THEREFOR, AND A THERMALY DECOMPOSABLE ALKALI-LIBERATING AMIDE ON SAID SUPPORT, SAID AMIDE HAVING THE GENERAL FORMULA: