EP0065053B1 - Diazotype material to be developed by heat, water or vapour - Google Patents

Description

• 1) Ils nécessitent une machine adaptée à leur mode de développement.
• 2) Ils ne résolvent pas entièrement le problème de la pollution, une certaine odeur d'ammoniac (qui se forme au cours du développement thermique) restant perceptible.
• 3) Leur stabilité avant emploi est plus faible que celle des produits diazotypes ordinaires par suite de leur tendance à former spontanément le colorant azoïque normalement produit seulement au cours des développements thermiques.
• 4) Certains d'entre eux donnent des tirages « concaves ou même roulent sur eux-mêmes peu de temps après leur traitement, par suite de l'absorption d'humidité par les produits chimiques nécessaires au développement thermique.

Currently known heliographic products developable by heat. They give excellent results, but have four drawbacks:

• 1) They require a machine adapted to their development mode.
• 2) They do not entirely solve the problem of pollution, a certain odor of ammonia (which forms during thermal development) remaining perceptible.
• 3) Their stability before use is lower than that of ordinary diazotype products due to their tendency to spontaneously form the azo dye normally produced only during thermal developments.
• 4) Some of them give "concave" prints or even roll on themselves shortly after their treatment, due to the absorption of moisture by the chemicals necessary for thermal development.

The patent FR-A-1 481 966 relates to a thermo-developable diazo heliographic copying sheet, comprising a support and on one of the faces thereof a photosensitive layer, deposited in the form of an aqueous layer, containing at least one diazo compound stabilized by an acid, characterized in that it comprises at least one developing layer, deposited in the form of a layer of organic solvent, containing at least one of the elements of a developing mixture containing at least one weak acid and strong base salt and a less volatile acid than the acid of the previous salt. The developer layer may contain additives such as binders, waxes and inclusion compounds. The photosensitive layer may contain binding agents regulating the penetration of the developing layer. However, the development is carried out at 90-115 ° C, in particular 100-110 ° C, and it fails to eliminate the four drawbacks mentioned above.

a) One of the aims of the invention is the production of diazotype paper, tracing and wire products which can be used both in machines with thermal development and in those “semi-wet”, as in those in dry.

In the case of ammonia machines, the ammonia solution will be replaced by water.

In the case of semi-wet machines, the developer will be replaced by water or simply eliminated if the machine has a drying section. In this case, the development will be purely thermal.

Certain “dry” machines will not be able to develop the above products, in particular in the case where the heating of their development section is known to be below 80 ° C., or even if they do not include the vaporization device. ammonia normally used, this device being necessary to vaporize water in the case of the use of products according to the invention.

b) Another object of the invention is therefore to propose a simple device, adaptable to these machines, allowing steam development.

c) Another object of the invention is the elimination of any odor of ammonia or amine during the heat treatment. This elimination is obtained inter alia by the use, as alkaline agents of the development system, of alkaline earth semi-hydroxides of volatile acids. These products have the particularity of reacting hot, through their OH group, with ammonium or amine salts to release a base and simultaneously release a weak acid capable of cold recombination with excess base to form an odorless salt.

d) Another object of the invention is to provide diazotype products which can be developed by heat, steam or water, with a stability before use known to be superior to that of currently known thermal development papers.

e) Another object of the invention is the production of diazotype products with thermal development, with steam or with water, not having an unacceptable concave "curling".

f) Another object of the invention is the production of water, steam or thermal development layers such that the finished product has a shiny surface.

In what follows, the term "steam developable should be taken in its broadest sense. Thus, for example, some of the products offered simply need to be moistened on their sensitive face: the quantity of water absorbed is absolutely sufficient so that, during drying at room temperature, the azo dye sought is formed with excellent performance.

Under these conditions, the development reaction will take 10 to 15 minutes. It is very accelerated of course if, after having subjected the sheet to a treatment with water, it is dried, as is the case in so-called “semi-wet” machines. In this case, development will take only a few seconds.

The currently known thermal development diazotypes operate from a chemical system contained in the face of the support opposite to that of the photosensitive layer. Thermal development takes place at 110 ° C, takes about 10 seconds and produces ammonia. This gas passes through the support and will form the azo dye in the layer on the front of the support. It follows that this gas must be very well blocked in the development section of the machine, on pain of seeing it get lost, this reducing the development power. In fact, the simple heating of a sheet of this type in the open air leads to the formation of only a very small quantity of dye, the ammonia escaping before having had the possibility of raising the pH of the sensitive layer sufficiently to produce the desired dye.

It will therefore be understood that such a product is absolutely unsuitable for the aim pursued by the present invention, which is to produce diazotype products developing on machines intended for other modes of development.

In other words, the products which are the subject of the invention must develop completely at 80-90 ° C. in the presence of humidity, without a tight contact being made between the support and the heat source.

This is both an essential condition and an essential difference with currently known thermal products.

The reactions leading to the type of development sought are obtained by the action of temperature, humidity or both, on a set of chemicals contained in one or more layers.

The development principle of reacting an ammonium or amine salt with an alkaline salt to release ammonia or an amine is known per se. It has been described in particular in French patent 1,127,337, which has since been abandoned, and therefore does not form part of the claims of the present invention.

Such a system can be represented by the following equation:

The ammonia and water formed develop the diazo image. Amine salts can also be used.

The object of the invention is the use of a set of physicochemical factors encompassing numerous products not described in the literature making it possible to obtain diazotype products stable before use, using the above principle to obtain the development as specified above.

• 1) La disposition des couches réactives.
• 2) La présence, la nature et la disposition des produits empêchant l'interpénétration des couches.
• 3) La présence de substances empêchant le lavage du sel de diazonium par la couche aqueuse que l'on lui superpose.
• 4) La présence de sels d'acide ou de composés d'inclusions d'acides, capables d'absorber à température ambiante, l'humidité et les bases éventuellement produites, pour former un sel stable les restituant ou non au cours du développement.
• 5) L'emploi de sels symétriques ou asymétriques de l'éthylène diamine, de la diéthylène-triamine, de la triéthylène-tétramine, de l'hexaméthylène-diamine, donnant avec certains sels d'ammonium ou d'amine des mélanges à point de fusion réduit ainsi qu'un développement sans contact amélioré par suite de leur volatilité plus faible.
• 6) L'utilisation comme produits de stabilisation de la couche photosensible, d'acides incapables de migrer dans les couches adjacentes.
• 7) L'utilisation de couches dorsales freinant la pénétration d'humidité par le dos du support et absorbant l'alcalinité qui peut être présente.
• 8) La séparation des produits réactionnels au moyen de pigments inertes.
• 9) La présence, dans la couche externe, d'une cire hydrophobe fusible à la température de développement, ou d'un mélange de cires contenant au moins une telle cire.
• 10) L'utilisation, comme accélérateur de développement, de plastifiants liquides à la température de développement, utilisés comme composés solides d'inclusion, le plastifiant étant libéré uniquement au moment du développement.
• 11) L'emploi au moins partiel, comme agents alcalins de développement et de désodorisation, de dérivés alcalino-terreux mi-oxydes, mi-sels.
• 12) L'utilisation de sels d'acides faibles volatils pouvant donner lors du développement une réaction de précipitation avec l'acide fort de stabilisation de la couche photosensible, réaction libérant un acide faible volatil servant à absorber les odeurs résiduelles.
• 13) L'emploi du ou des copulants dans une couche autre que celle qui contient le sel de diazonium. La réunion de ces produits pour la production de colorants azoïques se fera seulement au moment du développement: On augmente ainsi considérablement la stabilité du système avant emploi.

The following list brings together the factors having a preponderant influence for obtaining products according to the invention:

• 1) The arrangement of the reactive layers.
• 2) The presence, nature and arrangement of the products preventing the interpenetration of the layers.
• 3) The presence of substances preventing the washing of the diazonium salt by the aqueous layer which is superimposed on it.
• 4) The presence of acid salts or acid inclusion compounds, capable of absorbing at room temperature, the humidity and the bases possibly produced, to form a stable salt restoring them or not during development.
• 5) The use of symmetrical or asymmetric salts of ethylene diamine, diethylene triamine, triethylene tetramine, hexamethylene diamine, giving point mixes with certain ammonium or amine salts reduced melting and improved contactless development due to their lower volatility.
• 6) The use as stabilizing products of the photosensitive layer of acids incapable of migrating into the adjacent layers.
• 7) The use of backing layers slowing the penetration of moisture through the back of the support and absorbing the alkalinity that may be present.
• 8) The separation of the reaction products by means of inert pigments.
• 9) The presence, in the outer layer, of a hydrophobic wax meltable at the development temperature, or of a mixture of waxes containing at least one such wax.
• 10) The use, as development accelerator, of plasticizers liquid at development temperature, used as solid inclusion compounds, the plasticizer being released only at the time of development.
• 11) The use, at least in part, as alkaline agents of development and deodorization, of alkaline-earth derivatives half-oxides, half-salts.
• 12) The use of salts of weak volatile acids which can give during development a precipitation reaction with the strong acid stabilizing the photosensitive layer, reaction releasing a weak volatile acid used to absorb residual odors.
• 13) The use of the coupler (s) in a layer other than that which contains the diazonium salt. These products are brought together for the production of azo dyes only during development: This considerably increases the stability of the system before use.

This set of conditions will henceforth be called "the list ...

In general, good products according to the invention are obtained if at least factors No. ^S 1, 2, 6 and 9 and, as desired, two to seven of the others are used correctly and simultaneously.

• a) une couche diazotype à deux constituants sensible à la lumière contenant un composé diazo sensible à la lumière, un constituant de couplage capable de se coupler avec ledit composé diazo pour former une matière colorante, et
  • - comme agent de stabilisation un acide non migrant,
• b) au moins une couche d'un système de développement à deux constituants déposé sur la couche sensible à la lumière ou au dos du support, l'un des constituants étant un sel d'amine ou d'ammonium stable à la chaleur, l'autre étant un sel de métal alcalin, et
  • - des cires fondantes au cours du développement et agissant comme véhicules pour favoriser ledit développement,
  • - des liants pour chaque constituant du système de développement, et éventuellement,
  • - des accélérateurs de développement, des composés d'inclusion retenant un acide et des plastifiants,

la couche sensible à la lumière étant déposée sous la forme d'une couche aqueuse, alors que la couche de développement la plus extérieure est déposée sous la forme d'une couche de solvant organique ; l'invention est caractérisée en ce que l'acide non migrant, stabilisant la couche sensible à la lumière vis-à-vis du précouplage, est choisi parmi un acide sulfamique N-substitué par un radical aliphatique ayant au moins 6 atomes de carbone, un dérivé monosalifié d'un polyacide avec une amine de 4 à 12 atomes de carbone, ou un sel symétrique ou asymétrique d'un ou plusieurs polyacides monosalifiés par une diamine ou polyamine.The subject of the invention is a diazotype material developable with water or with water vapor comprising a support carrying a pre-layer and a surface layer of:

• a) a two-component light-sensitive diazotype layer containing a light-sensitive diazo compound, a coupling component capable of coupling with said diazo compound to form a coloring matter, and
  • - as a stabilizing agent, a non-migrating acid,
• b) at least one layer of a two-component development system deposited on the light-sensitive layer or on the back of the support, one of the components being a heat-stable amine or ammonium salt, l the other being an alkali metal salt, and
  • - melting waxes during development and acting as vehicles to promote said development,
  • - binders for each constituent of the development system, and possibly,
  • - development accelerators, inclusion compounds retaining an acid and plasticizers,

the light-sensitive layer being deposited in the form of an aqueous layer, while the outermost developing layer is deposited in the form of an organic solvent layer; the invention is characterized in that the non-migrating acid, stabilizing the light-sensitive layer with respect to precoupling, is chosen from an sulfamic acid N-substituted by an aliphatic radical having at least 6 carbon atoms, a monosalified derivative of a polyacid with an amine of 4 to 12 carbon atoms, or a symmetrical or asymmetric salt of one or more polyacids monosalified by a diamine or polyamine.

• 1) Pour les points 1, 2, 3 et 5 de la liste mentionnée ci-dessus :
  • 1-1) Le système réactionnel comprend au moins deux produits (un sel alcalin et un sel d'ammonium et/ou d'amine) et est coulé en une seule couche, les deux produits étant utilisés sous forme de pigments broyés en présence d'un liant organique, un liant par pigment.

The following explanations will allow a better understanding of the principles used for the realization of the invention:

• 1) For points 1, 2, 3 and 5 of the list mentioned above:
  • 1-1) The reaction system comprises at least two products (an alkaline salt and an ammonium and / or amine salt) and is poured in a single layer, the two products being used in the form of ground pigments in the presence of 'an organic binder, a binder per pigment.

The binders will be chosen in such a way that they are not miscible (in order to ensure the separation of the reactants) while giving a final homogeneous dispersion which is not flocculated. This latter condition is essential, any flocculation causing penetration of the organic liquid (and of the binder still dissolved therein) into the adjacent layer, which reduces the speed of development.

Example 1 describes such a binder system. In this example, the immiscible binders are represented by Movilith 20 ^R (Hoechst) and Dinotal ^R (dyno Inustrier SA Norway).

• - Le SAIB^R (Kodak) et la Dercolyte S 85^R (Chevassus).
• - La Movilith 20^R et l'Uralac 36480^R.
• - Le Solpolac 300^R (Cafaro) et l'Ethylcellulose 100^R (Hercules).
• - Le Rhodopas M^R (Rhône Poulenc) et l'Ethylcellulose 100^R.
• - La Movilith 50^R et la Dercolyte S 85^R.
• - L'Uralac 45^R et l'Ethylcellulose 100^R.
• - L'Uralac^R et le Paraloïd B 66^R (Rohm et Haas).
• - Le Rhodopas M^R et le Paraloïd A T 10"
• - Le Solpolac 10^R et l'Uralac 45^R.
• - La Movilith 20^R et l'Alphtalat V AC 20/30^R (Hoescht).
• - La Dercolyte S 85^R et le Dynomin^R (Dyno).

Other similar mixtures are for example:

• - SAIB ^R (Kodak) and Dercolyte S 85 ^R (Chevassus).
• - The Movilith 20 ^R and the Uralac 36480 ^R.
• - Solpolac 300 ^R (Cafaro) and Ethylcellulose 100 ^R (Hercules).
• - Rhodopas M ^R (Rhône Poulenc) and Ethylcellulose 100 ^R.
• - The Movilith 50 ^R and the Dercolyte S 85 ^R.
• - Uralac 45 ^R and Ethylcellulose 100 ^R.
• - Uralac ^R and Paraloid B 66 ^R (Rohm and Haas).
• - The Rhodopas M ^R and the Paraloid A T 10 "
• - Solpolac 10 ^R and Uralac 45 ^R.
• - The Movilith 20 ^R and the Alphtalat V AC 20/30 ^R (Hoescht).
• - The Dercolyte S 85 ^R and the Dynomin ^R (Dyno).

The various examples described show the use of certain mixtures of this type. The photosensitive layer over which this mixture is poured will contain repellents preventing any penetration of the organic liquid from the reactive layer. Such penetration, causing binder in the lower layer, would in fact considerably slow down, during development, the reaction for neutralizing the acid present in the latter.

This waterproofing is obtained in example n ° 1 and that n ° 2 by the high concentration of the salts used in the photosensitive layer. The latter establish a total barrier to the penetration of the solvent of the second layer, which is one of the conditions of the invention.

The so-called "repellents" will include neutral mineral salts, soluble enough to be used in a concentration such that the overlay of organic liquid cannot soak the layer comprising them.

Such products are, for example, alkali and alkaline earth halides, certain stable ammonium salts such as NH ₄ Br, NH ₄ CI, that is to say incapable of spontaneously giving off ammonia. Their concentration can go up to 50% of the water used.

• - Les Méthylcelluloses,
• - Carboxyméthylcellulose,
• - Polyvinylpyrrolidones,
• - Alcools polyvinyliques,
• - Polyacrylates de sodium et d'ammonium,
• - Les gommes naturelles, etc.

In addition to these products, certain binders can help with this effect. Let us quote:

• - Methylcelluloses,
• - Carboxymethylcellulose,
• - Polyvinylpyrrolidones,
• - Polyvinyl alcohols,
• - Sodium and ammonium polyacrylates,
• - Natural gums, etc.

1-2) In the case where the development system is poured in two layers over the photosensitive layer, the first may very well be water-based. In this case, the repellant may be the ammonium or amine salt (or both) used for development.

The aqueous layer will also optionally include a product such as a thiocyanate which precipitates the diazonium salt from the photosensitive layer, thus preventing it from being "washed".

The pouring and drying of such a layer then presents no difficulty. This is described in Example 3.

The first development layer consists of an aqueous solution of ammonium sulfamate. The ammonium sulfocyanide serves to block any solubilization of the diazonium salt of the lower layer, by precipitating it in a completely insoluble form. The role of monoamonic phosphate will be specified later, as well as that of ethylene diamine monochlorhydrate, monoformate.

The second development layer consists essentially of a dispersion of sodium bicarbonate in toluene. This dispersion is obtained by grinding by means of one of the currently known means, such as a ball, sand or ball mill.

A binder intended to fix the organic layer on the first development layer is also added.

• 1-3) Le système réactionnel est coulé en une ou deux couches, au dos d'un support papier.

During steam development, for example, ammonium sulfamate, ethylene diamine monochloride monoformate and monoammonium phosphate dissolve and react with sodium bicarbonate to form ammonia and ethylene diamine. These two bases neutralize the acid sulfate of the photosensitive layer, which causes the formation of dye between the diazonium salt and the coupler used.

• 1-3) The reaction system is poured in one or two layers, on the back of a paper support.

These two cases are similar to the thermal development papers currently used. As we have specified, these products cannot be used for machines other than those with thermal development, because if the developer is not constructed in such a way as to prevent any leakage of ammonia, development does not take place , the gas escaping before it could be used to form the image.

It was therefore advisable to use, instead of ammonium salts, amine salts, with the hope that their lower volatility would eliminate the above drawback. In fact, in addition to the fact that such salts are very hygroscopic, which prohibits their use for obvious reasons of stability, the amines produced diffuse too slowly through the support because of their molecular weight, to be of possible use. .

However, the Applicant has found that the lightest diamine, ethylene diamine, is perfectly suited to the needs of the invention.

This diamine provides very many salts with strong acids. These salts are stable in the sense understood here: they do not release any base, even during prolonged storage. They are not hygroscopic. Particularly interesting are certain asymmetric salts, not described in the literature and therefore also claimed as new products. Of course, the use of these products can also be done when casting layers on the front of the diazotype product.

In general, the melting points of these substances are higher than desired, but the Applicant has found that almost all of them form eutectics with certain ammonium salts of strong acids. Mixtures are thus obtained which melt at around 100 ° C., which is more than sufficient for the aim pursued which is the release of ethylene diamine during a thermal reaction. This base easily diffuses through the support and develops the azo image on the other side without the need for any gas blocking device. Such a product will of course develop in thermal machines, but also in the drying section of semi-wet machines, which current thermal papers cannot do.

Steam development remains possible, although slower than that obtained with layers located above the photosensitive layer.

If such a system is poured in a layer, the ethylene diamine salt and the ammonium salt will be ground together with a binder and an organic liquid. The alkaline salt will undergo the same treatment. The mixture of the whole will be poured on the back or the face of a sensitized paper support.

If the system is poured in two layers, the first water-based one will contain the salt in solution. The additive will also be dissolved there, allowing a reduced melting point to be obtained. After pouring and drying, the second layer containing the alkaline salt suspended in an organic liquid will be poured in the presence of a binder, a wax and a development accelerator. This is described in Example 4.

The ethylene diamine salts which can be used for the purposes of the invention are, for example, the following ( ^O C):

The new asymmetric ethylene diamine salts are for example the following:

The lowering of the melting point (° C) obtained from some of these products is as follows:

In the case where the reaction systems are poured over the photosensitive layer, it is no longer necessary for the liberated amine to diffuse through the support. In this case, heavier polyamine salts can be used such as the salts of hexamethylene diamine, diethylene triamine, triethylene tetramine, etc.

We cite among others:

The last six products were not isolated, but used in solution.

All these products also give mixtures with a lower melting point. For example :

All the salts mentioned above are prepared in the same way: successive neutralization of the base by acids at pH 6 in water medium, the concentration being as high as possible, cooling and precipitation by alcohol or acetone if needed. Filtration, washing with acetone, drying.

1-4) The outer layer of the development system, whether on the face or on the back of the diazotype product, contains a wax as a waterproofing agent against external moisture.

It has been found, in fact, that many waxes are very well suited to the needs of the invention. They are waterproof at room temperature, but melt during development and therefore do not interfere with the reactions taking place at this time.

These waxes are more or less soluble in the organic liquids used, or else they are easily dispersed there.

• - Les Mobilwa^R ou Waxrex^R (Mobil)
• - Les cires oxazoline (I M C Chemie)
• - Les cires de paraffine
• - La cire de Carnauba
• - La cire animale
• - La cire Ceresine
• - La cire E L 90
• - La cire d'abeilles
• - La cire de Candélia
• - Les cires ester (Glycochemical)
• - Les Acrawax (Glycochemical).

All the examples describe the use of these waxes. As usable waxes, we will cite:

• - Mobilwa ^R or Waxrex ^R (Mobil)
• - Oxazoline waxes (IMC Chemie)
• - Paraffin waxes
• - Carnauba wax
• - Animal wax
• - Ceresine wax
• - EL 90 wax
• - Beeswax
• - Candélia wax
• - Ester waxes (Glycochemical)
• - Acrawax (Glycochemical).

This list is by no means exhaustive. Of course, mixtures of waxes can be used. It remains desirable then that at least one of these waxes is fusible at the envisaged development temperature.

Example 8 mentions such a mixture. It will be observed that this example describes the production of a lacquered layer with thermal development. An incidental purpose of the mixture described is to give the finished product an increased gloss, which is a desirable characteristic of lacquered layers.

1-5) The precoat, which is in itself similar to those used for the production of so-called “dry” papers in that it contains a pigment and a film-forming binder dispersed or dissolved in water, and that it is poured onto the paper support before the photosensitive layer in a manner known per se, may also contain a product which is a barrier to organic solvents or which waterproofs water, thereby helping to reduce the absorption of atmospheric moisture by the dorsal face of the support.

• 1-6) Des paragraphes précédents, on déduira que le produit selon l'invention peut comporter jusqu'à 5 couches, à savoir :
  • - Précouche (à base d'eau)
  • - Couche photosensible (à base d'eau)
  • - Couche dorsale (à base d'eau, pour rétablir l'à-plat)
  • - Première couche thermosensible (à base d'eau, sur le recto)
  • - Deuxième couche thermosensible (à base de solvant organique, sur le recto).

This is described in Example 3.

• 1-6) From the preceding paragraphs, it will be deduced that the product according to the invention can comprise up to 5 layers, namely:
  • - Pre-coat (water-based)
  • - Photosensitive layer (water-based)
  • - Back layer (water-based, to restore flatness)
  • - First heat-sensitive layer (water-based, on the front)
  • - Second heat-sensitive layer (based on organic solvent, on the front).

Very few machines are capable of achieving such a superposition of layers at once.

It is perfectly possible, however, and this is one of the aims of the invention, to combine the first two layers into one provided that the whole is formulated in such a way that the products of the first layer are not washed by the second layer.

Example 7 shows how to do this. In this example, the washing of the diazonium salt is prevented by the sodium sulfocyanide of the next layer which precipitates it in a particularly insoluble form.

2) For points 4, 6, 7, 8 and 9:

The increase in stability of the whole system is obtained by various measures which touch on the reasons for the instability of diazotype products with thermal development.

The means proposed by the invention do not relate to reasons such as poor drying of the aqueous layers. However, it is recommended to dry with less than 3% water.

It is also recommended to pour all the layers in one go to avoid any intermediate recovery of humidity.

On the other hand, the invention proposes a series of means capable of blocking the action of humidity on the sensitive sheet, once the packaging is open, as well as reducing such action in the event that the manufacturing standards do not have not been fully respected.

The action of humidity on the sensitive thermal product is easy to understand.

Most of the active chemicals used are soluble in water. Some are hygroscopic. If moisture is absorbed by the system, there is partial solubilization, diffusion of the products, reaction producing alkaline and volatile substances and finally spontaneous formation of dye.

Such a process takes place during storage if the diazotype products have been improperly dried. It also takes place after opening the packaging at the time of use.

• 2-1) La couche dorsale aqueuse contient à la fois un acide assez fort et non volatil et une émulsion à base de silicone. La concentration de l'acide sera de 1 à 5 %. Celle de l'émulsion de silicone, de 0,5 à 2 %.

The following means are proposed to increase stability.

• 2-1) The aqueous backing layer contains both a fairly strong and non-volatile acid and a silicone-based emulsion. The acid concentration will be 1 to 5%. That of the silicone emulsion, from 0.5 to 2%.

The role of the acid is to fix any volatile base that may form on the face of the previous sheet in the packaging. The role of the silicone emulsion is to block the diffusion of moisture from the back, through the support, towards the face, during the exposure of the sheet to the open air before its use.

Non-volatile acids which can be used are, for example, tartaric, sulfamic, citric, oxalic, etc.

• 2-2) Les produits réactionnels sont mieux séparés, par l'emploi d'une certaine concentration de pigment inerte. De tels pigments sont, par exemple, les silices, kaolins, talcs, craies, calcites, dolomies, carbonate de calcium, sulfate de calcium ou de baryum, etc. Les concentrations peuvent varier de 20 à 100 % du produit actif. Ces agents de séparation peuvent être utilisés, que le système soit coulé en deux couches ou en une.

Such protection is described in Example 1.

• 2-2) The reaction products are better separated, by using a certain concentration of inert pigment. Such pigments are, for example, silicas, kaolins, talcs, chalks, calcites, dolomites, calcium carbonate, calcium or barium sulphate, etc. The concentrations can vary from 20 to 100% of the active product. These release agents can be used whether the system is poured in two layers or in one.

Example 3 describes a layer comprising such an agent (calcium sulphate).

2-3) The solubilization and migration under the influence of the humidity of the stabilizing acid of the photosensitive layer is reduced by the use of an sulfamic acid N-substituted by an aliphatic radical having at least 6 atoms of carbon or a monosalified derivative of a polyacid with an amine of 4 to 12 carbon atoms, or a symmetrical or asymmetric salt of one or more polyacids monosalified by a diamine or polyamine.

• - L'acide N-hexylsulfamique
• - Le sulfate acide d'hexylamine
• - Le bisulfate acide d'hexaméthylène diamine
• - Le sulfate acide, phosphate diacide d'hexaméthylène diamine
• - Le sulfate acide, maléate acide d'hexaméthylène diamine
• - Le sulfate acide de laurylamine
• - Les bisulfate acide de diéthylène triamine
• - Les bisulfate acide de triéthylène tétramine.

Such acids are for example:

• - N-hexylsulfamic acid
• - Acid hexylamine sulfate
• - The hexamethylene diamine bisulfate acid
• - Acid sulfate, diacid phosphate of hexamethylene diamine
• - Acid sulfate, acid hexamethylene diamine maleate
• - Laurylamine acid sulfate
• - Diethylene triamine acid bisulfate
• - Triethylene tetramine acid bisulfate.

• 2-4) L'une, l'autre ou les deux couches composant le système réactionnel comporte un ou plusieurs sels capables d'absorber à froid l'humidité et/ou l'ammoniac ou l'amine pouvant se former sous l'influence de cette humidité, en donnant un nouveau sel stable à température ambiante, mais décomposable entre 80 et 100 °C, c'est-à-dire au cours du développement, en relâchant les produits qu'il avait fixés.

These products cannot leave their layer to migrate into that containing the alkaline salts, to neutralize them, a phenomenon which is one of the reasons for the instability in storage of certain heat-sensitive products.

• 2-4) One or the other or the two layers making up the reaction system comprises one or more salts capable of cold absorbing moisture and / or ammonia or amine which can form under the influence of this humidity, giving a new salt stable at room temperature, but decomposable between 80 and 100 ° C, that is to say during development, by releasing the products which it had fixed.

Such substances are, for example, monoammonium phosphate, monosodium or monopotassium phosphate, etc.

Example 5 specifies the use of monosodium phosphate ground with ammonium nitrate.

This product reacts only very poorly with nitrate at a temperature far too high to be of any interest in steam development systems.

On the other hand, at ordinary temperature, it absorbs water well from ambient humidity and ammonia which can form to give monosodium monoammonic phosphate: P0 ₄ HNaNH ₄ , 4 H _P O.

This product is perfectly stable at ordinary temperature and decomposes on melting (98 °), during development, giving back the ammonia and water it will have absorbed:

In this way, greater stability of the sheet is obtained in humid air (before use), without reduction of the development power.

Example No. 3 and Example No. 4 mention, for the same purpose, the use of monoammonium phosphate in a layer comprising other salts.

Salts also having a certain absorption capacity for humidity and volatile bases but without having the same ease of restitution, can also be used.

Such are for example: BeC1 ₂ , BeS0 ₄ , LiCI, ZnC1 ₂ , LiF, as well as alkaline monotartrates and monooxalates.

Another way to apply this principle is to use inclusion compounds of the urea / organic acid type in pigment form.

• 2-5) Dans le cas où le système de développement comporte des sels d'amines ou de polyamines, on pourra lui adjoindre, pour augmenter la stabilité, des produits capables de former à froid des composés d'inclusions stables avec ces amines (et donc de les fixer si elles se forment au cours du stockage), mais aptes à les relâcher à chaud sous l'influence de l'humidité.

Under the action of humidity, the inclusion compound is destroyed, the acid released. As the action of humidity also results in the appearance of a base, the latter is at least partially taken up by the acid, giving a salt. During hot development, this salt is hydrolyzed and loosens its base. The urea / sebacic acid compound of Example No. 7 is used for this purpose.

• 2-5) In the case where the development system includes salts of amines or polyamines, it may be added to it, to increase stability, products capable of cold forming stable inclusion compounds with these amines (and therefore to fix them if they form during storage), but able to release them hot under the influence of humidity.

• - Le tétrachlorobisphénol A (Monsanto)
• - Le tétrabromobisphénol A (Dow)
• - L'hexachlorophène (Sindar)
• - Le bithionol (Actamer) (Monsanto)
• - Le bisphénol A (Dow)
• - Le 4,4'-thiobis (6-t-butyf m-crésol) (Monsanto)
• - Le 2,2'-méthylène bis (4-méthyl-6-t-butylphénol) (American cyanamid).

Such products are for example:

• - Tetrachlorobisphenol A (Monsanto)
• - Tetrabromobisphenol A (Dow)
• - Hexachlorophene (Sindar)
• - Bithionol (Actamer) (Monsanto)
• - Bisphenol A (Dow)
• - 4,4'-thiobis (6-t-butyf m-cresol) (Monsanto)
• - 2,2'-methylene bis (4-methyl-6-t-butylphenol) (American cyanamid).

Example 1 describes the use of such a product.

3) Point 10 of the list deserves special attention.

The Applicant has found that certain liquid plasticizers considerably accelerate the speed of development of thermal or steam developing papers, increasing their capacity to develop without direct contact, and reduce the haze effect given by certain pigments. Simultaneously, unfortunately, they clearly reduce the stability before use of diazotype products. The reason is certainly that the liquid plasticizers act as a partial solvent for the binders used and promote, as a "vehicle", the contact between the chemicals, thus causing premature reactions. It was therefore advisable to mask the plasticizers in question until the time of development.

• On sait que certains composés d'inclusion du type urée/plastifiant sont employés industriellement depuis une vingtaine d'années dans des systèmes de collage à chaud : à la fusion de l'urée, le composé interne (le plastifiant) est libéré pour la réaction de collage.

A marked improvement in stability is obtained if the plasticizer is dispersed in the precoat or the emulsion, but a very superior technique is as follows:

• It is known that certain inclusion compounds of the urea / plasticizer type have been used industrially for about twenty years in hot bonding systems: when the urea melts, the internal compound (the plasticizer) is released for the reaction. lift-off.

It turns out that certain urea / plasticizer or thiourea / plasticizer compounds are particularly suitable for the products that concern us. They are stable solids, easy to grind. The action of water or steam dissolves urea or thiourea and releases the product contained in the crystal lattice. Development is thus accelerated. Before development, the plasticizer, hidden in a solid crystal lattice, has no influence on the stability of the product.

Practice shows that only plasticizers of linear structure enter the crystalline mesh of urea. This, while limiting the number of possibilities, still leaves a huge choice since all alcohols, esters, ketones of more than 8 carbon atoms can be used.

The preparation of these products is extremely simple. A 20% urea solution in hot methanol is used and the plasticizer to be included is added thereto (5 g for approximately 25 g of urea).

Most often, the product precipitates when hot. Leave to cool, filter, wash with methanol and air dry.

In general, the products mentioned contain 8 to 10 mol. urea / mol. plasticizer.

A quick product test consists of adding hot water to the crystals obtained: urea or thiourea dissolve. It floats on an oily liquid which is none other than the plasticizer.

• 1) Urée/stéarate de butyle
• 2) Urée/oléate d'éthyle
• 3) Urée/dodécanol
• 4) Urée/dioctyle adipate
• 5) Urée/dibutyl sébacate
• 6) Urée/acide oléique
• 7) Urée/acide stéarique
• 8) Urée/nonyl-phénol éthoxylé
• 9) Urée/propylène glycol distéarate
• 10) Urée/éthylène glycol dipalmitate
• 11) Urée/glycérine monooléate
• 12) Urée/maléate d'hexyle
• 13) Urée/butyl glycol stéarate
• 14) Urée/éthylène glycol stéarate
• 15) Urée/diéthylène glycol stéarate
• 16) Urée/diéthylène glycol oléate
• 17) Urée/palmitate d'éthyle
• 18) Urée/palmitate de cétyle
• 19) Urée/diéthyladipate
• 20) Thiourée/dibenzoate de triéthylèneglycol
• 21) Thiourée/tétradécylcyclohexane
• 22) Thiourée/1-5 dicyclohexylpentane
• 23) Thiourée/1-4 dicyclohexylbutane
• 24) Thiourée/n-amylcyclohexane
• 25) Thiourée/polyéthylèneglycol 8000
• 26) Thiourée/polyéthylèneoxyde
• 27) Thiourée/polyéthylèneglycol 4000
• 28) Thiourée/isovalérianate de citronellyle
• 29) Thiourée/laurylamide.

The following inclusion compounds have been found to be of particular interest:

• 1) Urea / butyl stearate
• 2) Urea / ethyl oleate
• 3) Urea / dodecanol
• 4) Urea / dioctyle adipate
• 5) Urea / dibutyl sebacate
• 6) Urea / oleic acid
• 7) Urea / stearic acid
• 8) Ethoxylated urea / nonyl-phenol
• 9) Urea / propylene glycol distearate
• 10) Urea / ethylene glycol dipalmitate
• 11) Urea / glycerin monooleate
• 12) Urea / hexyl maleate
• 13) Urea / butyl glycol stearate
• 14) Urea / ethylene glycol stearate
• 15) Urea / diethylene glycol stearate
• 16) Urea / diethylene glycol oleate
• 17) Urea / ethyl palmitate
• 18) Urea / cetyl palmitate
• 19) Urea / diethyladipate
• 20) Thiourea / triethylene glycol dibenzoate
• 21) Thiourea / tetradecylcyclohexane
• 22) Thiourea / 1-5 dicyclohexylpentane
• 23) Thiourea / 1-4 dicyclohexylbutane
• 24) Thiourea / n-amylcyclohexane
• 25) Thiourea / polyethylene glycol 8000
• 26) Thiourea / polyethylene oxide
• 27) Thiourea / polyethylene glycol 4000
• 28) Lemonellyl thiourea / isovaleranate
• 29) Thiourea / laurylamide.

The use of these products is in the form of pigment, ground in the usual way, in an organic liquid at a concentration of 50%. The suspension is added to the organic dispersion used anyway as a development layer, a dose of 20% by volume representing a good average.

Examples ^S 1, 3, 5 and 8 deal with the use of these products.

It should also be noted that some of these substances can be perfectly prepared by direct grinding in toluene medium, without the need to isolate them.

4) Point 11 of the list concerns the use of odor-reducing agents during or after development.

It should be noted that the latter is anyway very weak. Absolutely no odor is noticeable in the steam development. The odor during development in thermal machines is also practically zero. There remains the problem of semi-wet machines. In this case, in fact, the paper is wetted with water and then dried. Or, the product is heated in the open air. If therefore there is formation of a base excess, the latter diffuses into the atmosphere. To minimize this drawback, a weak acid fixing the excess base should be released at the same time.

However, the Applicant has found that certain new development agents, the alkaline earth semi-hydroxides, meet this condition.

• Me = métal alcalino-terreux (Ca, Sr, Ba)
• R =H
  • = (CH₂)_nCH₃ avec n = 1 à 4
  • = CH₂OH
  • = CHOHCH₃

These hydroxides correspond to the general formula:

• Me = alkaline earth metal (Ca, Sr, Ba)
• R = H
  • = (CH ₂ ) _n CH ₃ with n = 1 to 4
  • = CH ₂ OH
  • = CHOHCH ₃

• 1) HOCaOCO - CH₃+ NH₄X → HOCaX + CH₃COONH₄ (X = anion du sel).
• 2) HOCaX + NH₄X → CaX₂ + NH₃ + H₂O.

These products, mixed with appropriate ammonium (or amine) salts, give thermal reactions of the type:

• 1) HOCaOCO - CH ₃ + NH ₄ X → HOCaX + CH ₃ COONH ₄ (X = salt anion).
• 2) HOCaX + NH ₄ X → CaX ₂ + NH ₃ + H ₂ O.

At this stage, the diazotype product develops.

Then the ammonium acetate dissociates (hot):

The diazotype product finishes developing. An excess of NH ₃ may remain which, when cold, on leaving the machine, will recombine with acetic acid.

The odor is thus eliminated or greatly reduced.

Certain semi-hydroxides mentioned are described in the literature. Others are unknown.

Their preparation is very simple and follows the typical reaction: or :

The alkaline earth oxide or hydroxide in question is suspended in stirring in toluene, at a concentration of 500 g per 21 g approximately.

1 mol is added. of acid, in a few minutes, so as to regulate the reaction which is very exothermic. There is no problem in letting the temperature rise to around 70 °.

As soon as the smell of the acid has disappeared, which takes a few minutes to an hour, we filter, re-paste with acetone, filter, dry at around 100 ° or in the open air.

The yields are of the order of 80 to 100%.

None of the products has a melting point below 260 ° C in the anhydrous state.

The Applicant has noted that some of the products mentioned can be prepared from a hydroxide and an acid anhydride according to the reaction:

In this case, it has been noted that the sometimes very slow initiation of the reaction can be catalyzed by the addition of a few drops of water.

• HO-Ca-OCOH : Monohydroxyde Monoformiate de calcium
• HO-Ca-OCOCH₃: Monohydroxyde Monoacétate de calcium
• HO―Ca―OCOC₂H₅ : Monohydroxyde Monopropionate de calcium
• HO―Ca―OCOCH₂OH : Monohydroxyde Monoglycolate de calcium
• HO-Sr-OCOH : Monohydroxyde Monoformiate de Strontium
• HO―Sr―OCOCH₃ : Monohydroxyde Monoacétate de Strontium
• HO―Sr―OCOCHOHCH₃: Monohydroxyde Monolactate de Strontium
• HO―Ba―OCOH : Monohydroxyde Monoformiate de Baryum
• HO-Ba-OCO(CH2)4CH3: Monohydroxyde Monocaproate de Baryum.

The following list, without limitation, gives the constitution of a few products meeting the aims of the invention:

• HO-Ca-OCOH: Monohydroxide Calcium monoformate
• HO-Ca-OCOCH ₃ : Monohydroxide Calcium monoacetate
• HO ― Ca ― OCOC ₂ H ₅ : Calcium monohydroxide Monopropionate
• HO ― Ca ― OCOCH ₂ OH: Monohydroxide Calcium monoglycolate
• HO-Sr-OCOH: Monohydroxide Monoformate of Strontium
• HO ― Sr ― OCOCH ₃ : Monohydroxide Monoacetate of Strontium
• HO ― Sr ― OCOCHOHCH ₃ : Strontium Monohydroxide Monolactate
• HO ― Ba ― OCOH: Monoformate Barium Monoformate
• HO-Ba-OCO (CH2) 4CH3: Barium monohydroxide Monocaproate.

Example 5 describes a layer comprising one of these products.

5) Point n ° 12 is also of great interest. It takes advantage of an insolubilization reaction of the stabilizing acid to contribute on the one hand to the development of the diazotype product, on the other hand to reduce the odors of volatile bases.

If for example the stabilizing acid of the photosensitive layer is an acid sulphate, an acid phosphate or oxalic acid, and that in one of the other layers an alkaline earth salt of volatile acid is used in part, then, under the action of water or steam, we will form an insoluble salt, a volatile acid and possibly a base. For example, if the stabilizing acid is ethylene diamine acid sulfate and the alkaline earth salt calcium acetate, we will have the reactions:

Part of the acetic acid can be released to block any volatile base that may be present and to cancel its odor.

A part will be neutralized by the alkaline developing agent, for example C0 ₃ HK, to give potassium acetate, also developing agent.

The ethylene diamine acetate will likewise be split into potassium acetate and ethylene diamine, both development agents:

It should be understood, however, that this approach only represents development aid, but is not a sufficiently effective development system if used alone.

Example 7 includes this improvement. The salts which can be used for this purpose are the formates, acetates, and propionates of calcium, strontium, barium, zinc, aluminum and magnesium.

6) Point n ° 13 is very important in that it allows both greater manufacturing flexibility and that it provides a marked increase in stability before use of the thermal systems used.

As seen in Example No. 7, a large concentration (40%) of ethylene diamine disulfamate is used in the photosensitive layer. This layer does not contain a coupler. The latter is used in the overlay, in pigment form, in which the alkaline salt is also found.

• le 2-3-dioxynaphtalène
• l'acide 2-oxy-3-morpholinopropylenaphtoïque
• l'acéto-acétanilide
• le 2-4,2'-4' tétrahydroxydiphényle sulfure
• l'éthanolamide de l'acide alpharesorcylique, etc.
• Ces copulants permettent toutes les combinaisons de couleurs souhaitées.

The couplers which can be used for this technique of the invention are for example:

• 2-3-dioxynaphthalene
• 2-oxy-3-morpholinopropylenaphtoic acid
• acetoacetanilide
• 2-4,2'-4 'tetrahydroxydiphenyl sulfide
• ethanolamide of alpharesorcylic acid, etc.
• These couplers allow all the desired color combinations.

7) Mention was also made, in the preamble, of the problem posed by the concave curling of thermodevelopable products.

• 1) La quantité de produits chimiques utilisée est bien plus faible, ces produits étant dans une couche en contact direct avec la couche sensible.
• 2) Toutes choses égales, les produits étant sur la face recto, le tuilage est légèrement convexe, ce qui ne gêne pas.
• 8) L'invention propose enfin quelques améliorations aux machines de développement dites « à sec », afin de les rendre, toutes, capables de traiter les produits « à la vapeur », proposés.

This extremely annoying fact is due to the absorption of atmospheric moisture by the chemicals in the back layer: the support swells and the sheet curls after a delay, which can vary between a few minutes and a few weeks. This phenomenon is eliminated in the case of steam developing paper, for two reasons:

• 1) The quantity of chemicals used is much lower, these products being in a layer in direct contact with the sensitive layer.
• 2) All other things being equal, the products being on the front side, the curl is slightly convex, which does not interfere.
• 8) Finally, the invention proposes some improvements to the so-called “dry” development machines, in order to make them all capable of processing the “steamed” products offered.

The “dry” machines normally have a pump bringing the ammonia solution into a container, the “boiler”, heated by a resistance provided with a thermostat, where the ammonia gas is released from its solution and from where it diffuses the development section, itself provided with electrical resistances and a thermostat.

In the case of "steam" papers, the ammonia solution is simply replaced by water.

If the development proves to be insufficient, it is sufficient to set the thermostat of the "boiler" to a higher value and to (or to) do the same for the heating resistances of the development section. If necessary, one or more resistors will be added.

Another way is to preheat the water, before it enters the "boiler", using a diving resistance, for example.

The examples which follow will make it easier to understand the use of the various principles set out.

Example 1

On a paper support for diazotype products, a precoat of the type normally used for "dry" papers is first poured.

Then poured a backing layer consisting of an aqueous solution of oxalic acid at 3% and 1% dispersion of silicone resin "Rhodorsil 240" ^R from Rhône-Poulenc. (Waterproofing).

The following photosensitive solution is then poured:

The solution (1) is prepared from a solution of dilute sulfuric acid and 0.5 molecules of ethylene diamine.

The photosensitive layer is poured and dried. A dispersion of sodium bicarbonate (100 kg) is then prepared, ground in 150 l of toluene in a manner known per se, so as to have grains less than 10 microns.

• 5 kg de tétrachlorobisphénol A (stabilisant)
• 10 kg de toluène.

A first binder is added to this dispersion in the form of a volume of a 50% Movilith 20 solution (Hoechst) in toluene. A second dispersion is also prepared, consisting of 100 kg of ammonium sulfamate and 20 kg of ethylene diamine sulfamate, ground in 150 l of toluene, with 30 kg of calcium sulfate, in a manner known per se, so as to have grains smaller than 10 microns. 0.5 volume of Dynotal 03 XB is added to this dispersion and mixed with the first. These two binders are not miscible. 20% of a suspension of Wax EL 90 ^R at 20% in toluene is then added. (Fuse wax). Finally, a pre-ground dispersion of:

• 5 kg of tetrachlorobisphenol A (stabilizer)
• 10 kg of toluene.

This mixture is poured over the photosensitive layer and dried with hot air at 70 ° in 3-4 seconds. 6 to 15 g of products are deposited per m ² .

The heliographic product thus obtained develops in the usual way in thermal machines of the “Chapel” ^{R type} (Chambéry-France). It also develops with steam in so-called “dry” machines, in which the ammonia is replaced by water whose flow will be equal to that of the ammonia normally used. The temperature in the developing chamber will be 80-100 °.

This example uses the following principles from the list: 1-2-5-6-7-8-9.

Example 2

In the photosensitive solution of Example No. 1, the ethylene diamine acid sulfate is replaced by the same amount of hexamethylene diamine acid sulfate.

The outer layer is made up as follows: 100 kg of ammonium sulfamate and 50 kg of calcium carbonate (separation pigment) are ground in a manner known per se. 20 kg of the binder "Solpolac 300" ^R (Cafaro-Milan) are then added. Similarly, 100 kg of potassium bicarbonate are ground in 100 l of toluene and then 30 kg of a dispersion of “Mobilwax 31 U” ^R (fusible wax), 20% in toluene, is added. Finally, 10 kg of the inclusion compound: urea / dodecanol (masked plasticizer) are ground in 30 kg of toluene and 1 kg of Pliolite AC ^R (binder) of "Goodyear" is added thereto.

These three dispersions are mixed and poured over the photosensitive layer as already explained.

The product obtained shows a faster vapor development than that of Example 1.

This example uses the following principles from the list: 1-2-5-6-7-8-9-10.

Example 3

First, a precoat of the type usually used for “dry” diazotype papers is poured, to which 20-40% of Glascol HA ₂ (Allied Colloids) is added, as an agent preventing the passage of moisture through the back of the support.

• 1) Sulfamate d'ammonium : 30 % en poids par volume
• 2) Ethylènediamine monoformiate, monochlorate : 15 %
• 3) Phosphate monoammonique : 10 %
• 4) Sulfocyanure d'ammonium : 0,5 %:

On this precoat, the sensitive layer of Example 1 is poured, but without CINH ₄ . An aqueous solution is then poured onto the photosensitive layer containing:

• 1) Ammonium sulfamate: 30% by weight by volume
• 2) Ethylenediamine monoformate, monochlorate: 15%
• 3) Monoammonium phosphate: 10%
• 4) Ammonium sulfocyanide: 0.5%:

• 2) sert à diminuer le point de fusion de 1)
• 3) est un absorbeur d'ammoniac à froid, destiné à augmenter la stabilité,
• 4) élimine le lavage du sel de diazonium de la couche inférieure.

In this solution:

• 2) used to decrease the melting point by 1)
• 3) is a cold ammonia absorber, intended to increase stability,
• 4) eliminates the washing of the diazonium salt from the lower layer.

The backing layer of example # 1 is then poured.

• On broie :
• Phosphate monosodique 30 kg (absorbeur d'ammoniac à froid)
• Bicarbonate de sodium 70 kg (agent de développement)
• Acétate de calcium 10 kg (agent anti-odeur et de précipitation de l'acide de stabilisation)

dans 150 I de toluène, de façon à avoir des grains inférieurs à 10 microns.We finally pour the following overlay:

• We grind:
• Monosodium phosphate 30 kg (cold ammonia absorber)
• Sodium bicarbonate 70 kg (developer)
• Calcium acetate 10 kg (anti-odor and precipitation agent for stabilizing acid)

in 150 l of toluene, so as to have grains less than 10 microns.

• Ethylcellulose N 100: 2 kg
• Cire de paraffine (fusion 70°) : 15 kg.

The binders are then added:

• Ethylcellulose N 100: 2 kg
• Paraffin wax (70 ° fusion): 15 kg.

The whole is homogenized and flows over the previous layer while drying at 50-60 °.

The diazotype product thus obtained develops under the same conditions as that of Example No. 1.

If this product is treated in a semi-wet type machine, in which the developer is replaced by water containing a little wetting agent, a blue image is also obtained.

This example uses the following principles from the list: 1-2-3-4-5-6-7-9-12.

Example 4

• 1) Ethylènediamine monoacétate monosulfamate 60 % en poids/volume.
• 2) Nitrate d'ammonium 25 % en poids/volume.
• 3) Phosphate monoammonique 15 % en poids/volume.

First a precoat of a conventional type is poured. The emulsion of example No. 3 is then poured in. A first water-based back layer is then poured, constituted as follows:

• 1) Ethylenediamine monoacetate monosulfamate 60% w / v.
• 2) Ammonium nitrate 25% w / v.
• 3) Monoammonium phosphate 15% w / v.

In this mixture, 1) serves to decrease the melting point of the mixture. Furthermore, the ethylenediamine produced during development reduces the need for a perfect seal during heat or steam treatment. 3) is a stabilizing agent, absorbing ammonia which can form cold under the influence of humidity.

Finally, the second back layer is poured: 90 kg of potassium bicarbonate and 10 kg of sodium phosphate are ground in 150 l of toluene until the fineness of the grains is less than 10 microns.

5 kg of the inclusion compound Urea / dibutyl sebacate are ground in 20 l of toluene, so as to have a fineness of grains less than 10 microns and this dispersion is added to the previous one.

10 kg of Movilith M 50 ^R and 15 kg of Waxrex 2370 ^R wax (Mobil) are then added and the whole is homogenized.

This layer is poured as a second back layer and dried.

The development of the finished product takes place as already explained.

This example uses the following principles from the list: 1-4-5-6-9-10.

Example 5

• 50 kg de nitrate d'ammonium
• 20 kg d'hexaméthylène diamine monoformiate monosulfate
• 30 kg de phosphate monosodique
• 2 kg d'Inipol 002^R (de Prochinor - Paris) (Agent mouillant).
• 2 kg d'Alcreftal^R 1098 x 50 (liant) de Ashland Chemical.
• 8 kg de Movilith^R H 60 (liant).
• 150 1 de toluène.

On a pre-layer of the type used for the so-called “dry” products, the photosensitive solution of Example No. 1 is poured, as well as the same backing layer. The ground dispersion is then prepared to less than 10 microns:

• 50 kg of ammonium nitrate
• 20 kg of hexamethylene diamine monoformate monosulfate
• 30 kg of sodium phosphate
• 2 kg of Inipol 002 ^R (from Prochinor - Paris) (Wetting agent).
• 2 kg of Alcreftal ^R 1098 x 50 (binder) from Ashland Chemical.
• 8 kg of Movilith ^R H 60 (binder).
• 150 1 of toluene.

• 70 kg monohydroxyde monoformiate de calcium
• 30 kg bicarbonate de potassium
• 2 kg Inipol 0₀₂ ^R
• 20 kg cire de paraffine (fusion environ 70°)
• 2 kg Elwax^R 210 (Dupont) (liant).

A second dispersion is likewise prepared:

• 70 kg calcium monoformate monohydroxide
• 30 kg potassium bicarbonate
• 2 kg Inipol 0 ₀₂ ^R
• 20 kg paraffin wax (fusion around 70 °)
• 2 kg Elwax ^R 210 (Dupont) (binder).

The following are also ground: 5 kg of thiourea / triethylene glycol dibenzoate inclusion compound, 15 kg of toluene.

The three dispersions are mixed and the whole is poured over the photosensitive solution in the usual way. The finished product develops in the usual way.

This example uses the following principles from the list: 1-2-4-5-6-7-8-9-10-11-12.

Example 6

First pour the precoat of example n ° 3. On this pre-layer, a photosensitive solution prepared according to example n ° 1 is then poured into which the ammonium and sodium chloride are replaced by 25 kg of sulfamate of ammonium and 10 kg of ethylenediamine disulfamate, and the coupler removed.

The backing layer of example # 1 is then poured.

• 100 kg bicarbonate de sodium
• 10 kg acide 3-hydroxynaphtalène-2-carboxylique-morpholinopropylamide
• 10 kg Solpolac 300^R (liant)
• 15 kg cire Oxazoline OWR-170
• 150 kg toluène.

The following dispersion is then prepared, ground to less than 10 microns:

• 100 kg sodium bicarbonate
• 10 kg 3-hydroxynaphthalene-2-carboxylic acid-morpholinopropylamide
• 10 kg Solpolac 300 ^R (binder)
• 15 kg Oxazoline wax OWR-170
• 150 kg toluene.

• 10 kg composé d'inclusion urée/nonylephénoléthoxylé
• 20 1 toluène
• 0,5 1 Inipol 002^R
• 3 kg Uralac 45^R (liant)
• 2 kg Alprodur^R CP 646 (liant) de Hoechst.

A second dispersion is prepared:

• 10 kg inclusion compound urea / nonylephenolethoxylated
• 20 1 toluene
• 0.5 1 Inipol 002 ^R
• 3 kg Uralac 45 ^R (binder)
• 2 kg Alprodur ^R CP 646 (binder) from Hoechst.

The two dispersions are mixed and poured over the photosensitive solution in the manner already described.

The finished product develops as already specified.

This example uses the following principles from the list: 1-2-5-6-7-9-10-13.

Example 7

A pre-coat incorporated into the emulsion is prepared in order to pour the whole in a single layer:

This set is poured in the usual way. Normally, such a formula loses its pigment by friction in development machines, the latter not being fixed by a binder.

In this case, this point is unimportant, because two other layers are superimposed on the first.

The second layer will be made up as follows:

This layer is poured and dried as already indicated.

The backing layer will be for example that of example n ° 1.

The third layer is then prepared: as already explained, 70 kg of sodium bicarbonate, 20 kg of sodium phosphate and 10 kg of calcium acetate are ground into 150 I of toluene.

• 15 kg de Solpolac 10^R (liant)
• 5 kg cire Waxrex^R31 U (Mbbil)
• 3 kg Alphtalat^RV AC (liant) de Hoechst

Then we add:

• 15 kg of Solpolac 10 ^R (binder)
• 5 kg Waxrex ^R 31 U wax (Mbbil)
• 3 kg Alphtalat ^R V AC (binder) from Hoechst

• 5 kg du composé d'inclusion urée/acide sébacique en 10 kg de toluène, ajoute 2 kg de résine Aroplaz^R 2466 (liant) de Archer Daniels, puis ajoute ce mélange à la dispersion.

We also grind:

• 5 kg of the urea / sebacic acid inclusion compound in 10 kg of toluene, add 2 kg of Aroplaz ^R 2466 resin (binder) from Archer Daniels, then add this mixture to the dispersion.

We pour and dry in the usual way.

The development of the product thus prepared gives a dark image.

This example uses the following principles from the list: 1-3-4-5-6-7-8-9-12-13.

Example no.8

Lacquered layer.

On a support of the “tracing” type, a layer of sensitized lacquer is poured constituted as follows:

We manage to deposit approximately 4 g / m ² of dry product. We then pour the first overlay:

We manage to pour about 3 g / m ² of first overlay.

We then pour a back layer:

We then prepare the second overlay:

90 kg of C0 ₃ HNa and 10 kg of P0 ₄ H ₂ Na in 150 of toluene are ground and the following is added:

The whole is homogenized, then the dispersion is spread over the first overlay.

We manage to sink about 4 g / m ² of second overlay.

The constitution of the second overlay provides the finished product with a shiny surface.

The development of the layer thus obtained is carried out like that of paper and gives a brown image.

This example uses the following principles from the list: 1-4-5-6-7-9.

Claims (10)

1. A water-or steam-developable diazotype material comprising a support carrying a precoat and an overlaying layer of

a) a light-sensitive two component diazotype layer containing a light-sensitive diazo compound, a coupling component capable of coupling with said diazo compound to form a dyestuff, and

- a non-migrating acid as a stabilizing agent,

b) at least a two-component developing system layer coated on the light-sensitive layer or at the backside of the support, one of the components being a heat stable ammonium or amine salt, the other being an alkaline metal salt, and

- waxes melting during the development and acting as vehicles to promote said development,

- binders for each components of the developing system, and possibly,

- developing accelerators, inclusion compounds retaining an acid and plasticizers,

the light-sensitive layer being coated in the form of an aqueous layer, whereas the uppermost developing layer is coated in the form of an organic solvent layer, characterized in that the non-migrating acid stabilizing the light-sensitive layer against pre-coupling, is selected from the group consisting of a sulfamic acid N-substituted by an aliphatic radical having at least 6 carbon atoms, a polyacid derivative monosalified by an amine having 4 to 12 carbon atoms, or a symmetrical or assymmetrical salt of one or several polyacids monosalified by a diamine or polyamine.

2. A diazotype material according to claim 1, wherein the diazotype layer a) further comprises repulsive products preventing the penetration of the developing layer.

3. A water- or steam-developable diazotype material according to claim 1, wherein, when the two-component developing system is coated in the form of two adjacent layers, the amine or ammonium salt of the first layer, coated in the form of an aqueous layer on the light-sensitive layer, is useful both as the first component of the developing system and as a repulsive agent preventing the penetration of the second layer comprising the second component of the developing system, coated in the form of an organic layer.

4. A diazotype material according to any of claims 1 to 3, wherein the developing layer further comprises an inert pigment allowing a better separation of the two components and thus a better action of steam or water during development.

5. A diazotype material according to claim 2, wherein the repulsive product is selected from the group consisting of alkaline metal halide, alkaline earth metal halide, ammonium bromide and ammonium chloride.

6. A diazotype material according to claim 1 or claim 2, wherein the first component of the developing system is a mixture of an ammonium salt selected from ammonium sulfamate, ammonium nitrate, ammonium monophosphate and ammonium chloride, and of an amine salt selected from the group consisting of asymmetrical salts of ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, dimethylenediamine and trimethylenediamine.

7. A diazotype material according to any of claims 1 to 6, wherein the developing accelerators active only during the development are urea or thiourea inclusion compounds containing as a host esters, alcohols or ketones having more than 8 carbon atoms.

8. A diazotype material according to claim 4, wherein the inert pigment used to separate the components for higher stability prior to use and better activity during the steam action, are selected from the group consisting of the silicium oxides, kaolins, talc, chalks, calcites, dolomites, calcium or baryum carbonates.

9. A diazotype material according to claim 1, wherein the developing layer further comprises a supplementary stabilizing acid compound contained in an organic solvent layer, its acid function being blocked under normal conditions but becoming active when subjected to moisture, said stabilizing acid being selected from inclusion compounds of urea and aliphatic acids of more than 5 carbon atoms, and by products having a weak acid function but able to act as a host in order to block the possibly formed amines by forming a clathrate, said weak acids being selected from bisphenol and derivatives thereof, hexachlorophene and bithionol.

10. A diazotype material according to claim 1, wherein the developing layer further comprises a developing aid used in the form of pigments selected from the group consisting of calcium, strontium and baryum semi hydroxides of formic, acetic, propionic, butyric, caproic, glycolic or lactic acids, said substances being able to act simultaneously as developing aids owing to their OH-group, and as ammonia smell hiding products owing to their volatile acid group, and as precipitant of the stabilizing agent of the light sensitive layer, said acid being of the type represented by the acid sulfates, the acid phosphates or the oxalic acid.