CH618640A5 - Recording or reproduction material and its use - Google Patents

Abstract

The material comprises a substrate coated with a sensitive layer containing a colour-forming compound capable of reacting with a phenol group so as to form a dye. The sensitive layer contains a urethane capable of generating a phenol or a naphthol under the effect of input of energy; this urethane is a derivative of certain phenols or naphthols and an isocyanate. The fixing of the phenol group has the effect of considerably increasing the stability of the sensitive layer.

Description

The present invention relates to a recording or reproducing material comprising a support coated with a sensitive layer containing a chromogenic compound capable of reacting with a phenol or a naphthol to give rise to a colored trace.

Many materials of this type are already known. In US Patent No. 3451338 is described a material containing spiropyrans which, after complexing with a phenol, give rise to a colored trace of merocyanine.

In the American patent N ° 3674535 or in the French patent N ° 2172386 are described materials based on derivatives of triphenylmethane which react with phenols to generate a colored trace under the action of heat. Similar materials are known from US Patent No. 2663654 in which the chromogenic compounds are ferric salts.

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Finally, there are also known from French patent No. 1336307 materials containing diazo compounds which react with free phenols to generate colored traces.

All these reproduction or recording materials and their methods of implementation, however, have very significant drawbacks which hinder their very wide distribution: on the one hand, the phenols oxidize quickly and the reproductions age quickly; on the other hand, it is necessary to prevent them from reacting too quickly and causing untimely color reactions. We must therefore seek to stabilize them to prevent them from reacting prematurely, but this necessary stabilization is itself troublesome, because it then slows down the reaction rate of the compound and does not chemically block the reactive sites of the phenol.

The present invention makes it possible to avoid these drawbacks. For this purpose, the material is characterized in that the sensitive layer also contains a urethane capable of generating in situ a phenol or a naphthol, said urethane being derived from an isocyanate and from a benzene mono-, di- or triphenol. or naphthalene in which the aromatic ring is or is not substituted, with the exception of 2,3-bis (alkylcarbamoyloxy) naphthalenes of formula:

.GOLD

■ N = C = 0 + H-0

in which R represents an alkylcarbamoyl group in which the alkyl chain contains from 1 to 4 carbon atoms and Y represents a hydrogen atom or the group R.

Compounds excluded from the scope of the invention are already known in the art ("US Defensive Pub." No. 905004, of December 19, 1972).

The urethane present in the layer results from the blocking, by an isocyanate, of the hydroxyl groups of a phenolic or naphtholic compound. Under the action of an energy supply or of contact with certain liquid or gaseous fluids (as will be described in detail below), the urethane present in the layer can then release a phenol or naphthol which reacts with the chromogenic compound.

In the absence of external energy supply or of contact with a fluid, urethane is a very stable compound; the recording or reproducing material according to the invention therefore has very high storage stability and greatly increased resistance to aging phenomena. The phenols which may be used in the context of the invention are the benzene mono-, di- or triphenols in which the benzene ring may or may not be substituted, or also the naphthalene derivatives. Mention may be made, without limitation, of the most commonly used phenols: phenol, resorcinol, pyrogallol, phloroglucinol, 2-3 dihydroxynaphthalene, 4-25 4'isopropylidenediphenol, etc.

As we know, urethanes are obtained by reacting an isocyanate with a phenol. The reaction is written:

H 0

»OV-N-C-O— <0

R

isocyanate

All isocyanates are capable of being suitable, within the framework of the invention, for blocking phenols. It is obviously more advantageous to use the simplest and most common among which there may be mentioned, without limitation, phenylisocya-nate, toluylene diisocyanate, 1-5 naphthene-lene diisocyanate, 4-4 diphenylmethane diisocyanate or 1-6 hexamethylene diisocyanate, etc.

To prepare the desired urethane, a stoichiometric amount of a reactive isocyanate is reacted on a phenol in an anhydrous and non-reactive solvent in the presence of a known catalyst, such as, for example, an aliphatic tertiary amine such as triethy -the mine. The reaction product is then collected, filtered, washed and dried. The decomposition reaction of the urethanes thus prepared takes place between 80 and 200 ° C.

The chromogenic compounds used are not characteristic of the invention: they are all the chromogenic compounds capable of reacting with a phenol to give a colored reaction. Among them, mention may be made of indolinic or benzothiazolic spiropyrans, triphenylmethane derivatives, ferric salts, as well as certain diazo compounds.

In general, the weight ratio between the chromogenic compound and the urethane can be between 0.01 and 10,

but preferably between 0.1 and 1.

In some cases, it may be useful to add a binder to the sensitive layer. This will preferably be chosen from polyvinyl alcohols, polyvinyl esters, acrylic esters, homo- or copolymers based on polyvinyl chloride or any other binder well known to those skilled in the art.

During the decomposition of the urethane into a phenol or naphthol and an isocyanate, the latter could, under certain conditions, be released, which can be troublesome. Also, the sensitive layer contains products capable of reacting with isocya-nate in order to keep it in the layer. Among these, there may be mentioned, without limitation, aliphatic alcohols, poly-

thers, hydroxylated polyesters, these bodies all having free OH groups which react with the isocyanate. The supports which can be used are the supports usually used for recording or reproduction, such as paper, plastics, metals, the possible binder of the layer being adapted to said support.

To implement these recording or reproduction materials, there are several possible methods:

A first method consists in decomposing the urethane present in the sensitive layer by supplying energy, preferably thermal energy, which decomposes it so as to release the phenol which reacts with the chromogenic compound.

In order to lower the processing temperature of the sensitive layers described above, it may be advantageous to incorporate said sensitive layer (or in the form of an underlayer or overlay) into a catalyst for decomposing l urethane capable of lowering the decomposition temperature thereof. It is thus possible to reach a decomposition temperature which can be lowered to around 80 ° C.

55 Among the catalysts, there may be mentioned, without limitation:

- ammonia

- bases, such as soda, potash, etc.

- the aliphatic amines and preferably the aliphatic tertiary amines of general formula:

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/ Rl

N — R2 with Rx R3 having from 1 to 10 carbon atoms. R3

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Cyclic aliphatic tertiary polyamines such as, for example, hexamethylenetetramine, triethylenediamine,

etc.,

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- hydroxylated amines (or amino alcohols) such as, for example, mono-, di- or triethanolamine, 2-amino-1-butanol, tri (hydroxymethyl) aminomethane, etc.,

- organic or mineral ammonium salts such as carbonates, hydrocarbonates, formates, Oxalates, benzoates, etc.,

- morpholine derivatives such as morpholine, N-methylmorpholine, 2-6 dimethylmorpholine, N-amino-ethylmorpholine, etc.,

The metal salts of organic acids, the metals which can be used in particular being tin, calcium, lead, zinc, aluminum, etc., the organic acid having from 3 to 18 carbon atoms and preferably from 5 to 10. Mention may in particular be made of lead octoate, zinc octoate, calcium naphthenate, etc.,

- organotin salts such as for example dilauryldibu-tyletain,

- products or pairs of products producing ammonia under heat and in particular:

- ■ urea, thiourea and their derivatives,

- heat decomposable ammonium salts such as for example ammonium carbonate, ammonium benzoate, etc.,

- the pairs of products which, by reaction to heat, produce ammonia such as the pairs of products described in BF N ° 1403004 (ammonium salt of strong acid + metallic compound) or such as the pairs of products described in BF N ° 1418156 (strong acid and weak base salt + weak acid and strong base salt).

In the case of thermal recording, this can be done using a heating head or any other means well known to those skilled in the art: the colored trace then appears, there or the material has been heated.

In the case of thermal reproduction, the material which then comprises a photosensitive chromogenic compound is exposed one or more times according to the various known methods, so that said chromogen only reacts selectively with the phenol subsequently released by the addition of thermal energy. One can also make thermal reproductions according to the infrared thermocopy process, such as the process known under the name Thermofax. The chromogenic compound can then be any. All of these methods are known per se and are outside the scope of the invention.

Another process for using the materials according to the invention to enable the release of phenol and its reaction with the chromogenic compound consists in bringing a fluid into contact with the sensitive layer according to the invention, this liquid or gaseous fluid having the property to unblock the phenol, that is to say to decompose the urethane, and allow its reaction with the chromogenic compound.

Among the fluids capable of decomposing urethane and releasing phenol, there may be mentioned in particular, without limitation:

- ammonia (gas) or ammonia (liquid),

- bases, such as soda, potash, etc.,

- the aliphatic amines and preferably the aliphatic tertiary amines of general formula:

/ Rl

N — R2 with Rj, R2, R3 having from 1 to 10 carbon atoms. R3

- ■ cyclic aliphatic tertiary polyamines such as, for example, hexamethylenetetramine, triethylenediamine, etc.,

- hydroxylated amines (or amino alcohols) such as, for example, mono-, di- or triethanolamine, 2-amino-1-butanol, tri (hydroxymethyl) aminomethane, etc.,

- organic or mineral ammonium salts such as carbonates, hydrocarbonates, formate, Oxalates, benzoates, etc.,

- morpholine derivatives such as morpholine, N-

5 methylmorpholine, 2-6 dimethylmorpholine, N-amino-ethylmorpholine, etc.

It is obvious that fluids in gaseous form can only be used in reproduction, in order to develop the material previously exposed according to known methods. When the fluid io is in liquid form, it is possible to make recordings on a material in accordance with the invention using a point or an ink stylus of well known type, the ink being replaced by the phenol release fluid.

Reproductions can also be made, as in the case where the fluid is gaseous, the development of the material taking place by immersion in said liquid. In all cases, it may be useful, in order to speed up the reaction and dry the material, to slightly heat it, to a temperature above 40 ° C, but below the unlocking temperature of phenol (decom- 20 thermal position of phenylurethane).

A particularly important application of the invention is diazotypy, in all its forms, whether the development is thermal, semi-wet or gaseous using ammonia. The invention then provides considerable progress over the diazotypy materials well known to those skilled in the art: since the phenol is blocked by an isocyanate in the form of a urethane, there is no risk of precopulation and the material can be stored for an indefinite period, without the slightest appearance of phenol in the layer. This can significantly limit the amount of stabilizing aids, generally used in these layers. In the case of diazotypy, it is not necessary to use a binder to combine the diazo compound and the urethane. The proportions by weight between the diazo compound and the coupling agent (that is to say urea-35 thanne) can vary between 0.3 and 3. In all cases, the fluids used for the development can be pure or in solution.

The invention will be better understood using the following exemplary embodiments.

40 Example 1:

8 g of 2-3 dihy-droxynaphthalene, 100 g of dried methyl ethyl ketone (MEK) and a few drops of triethylamine are placed in a three-necked flask fitted with a stirrer, an ascending cooler and a dropping funnel.

45 12 g of phenylisocyanate are added dropwise using the dropping funnel, with stirring: the mixture is slightly heated; a white precipitate is formed which is filtered, washed with MEK and dried. This precipitate is naphthyldiphenylurethane. The following composition is deposited on a base paper coated with a barrier layer to the floor-50 layers:

- 1 g of naphthyldiphenylurethane,

- 10 g of a 10% solution in tetrahydrofuran of AXRH resin (vinyl copolymer from the company Rhône-Poulenc). The deposited layer is dried at 50 ° C.

55 On the other hand, a grinder is prepared:

- 0.4 g of isopropyl 3'3 'dimethyl, 6 nitro, 8 methoxyspiro (2H-1 benzopyran-2,2' indoline),

- 10 g of a 10% aqueous solution of Rhodoviol 4/125 P (polyvinyl alcohol from the company Rhône-Poulenc).

60 This composition is deposited with Meyer's rule over the previous layer and dried at 70 ° C.

A heating head brought to 150 ° C causes a blue-black trace on a light background.

65 Example 2:

The procedure is as in Example 1, replacing the 2-3 dihy-droxynaphthalene by the same amount of 4-4 'isopropylidenediphenol (Bisphenol A) and the phenylisocyanate by the amount

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stoichiometric equivalent of 2-4 toluyen diisocyanate (TDI).

We disperse in a grinder:

- 20 g of bisphenol blocked with TDI,

- 100 g of Rhodoviol 4/20 (polyvinyl alcohol from the company Rhône-Poulenc) at 10% in water,

- 2 g of lactone violet crystal,

- 3 g of zinc oxide,

- 10 g of ethylene glycol.

This composition is deposited on a support at a rate of 5 g per m2 using a Meyer rule and dried. A thermal head brought to 150 ° C causes the formation of a blue trace on a light background.

Example 3:

The procedure is as in the previous examples, adding to a molecule of pyrogallol three molecules of phenylisocyanate. The blocked pyrogallol which precipitates is collected and dried.

In a ball mill, vigorously disperse:

- 5 g of ferric stearate,

- 3 g of blocked pyrogallol,

- 20 g of Rhovinal B 10 (butyral polyvinyl from the company Rhône-Poulenc) at 10% in isopropanol,

- 10 g of 1-4 butanediol.

After coating on paper, a thermal head brought to 120 ° C leads to the formation of dark brown traces on a white background.

Example 4:

The following composition is prepared:

- naphthyldiphenylurethane 2.5 g

- 4 diazo 2-5 dibutoxyphenylmorpholine chlorozin-

cate 3 g

- citric acid 1.5 g

- water 175 cm3

- methyl ethyl ketone 175 cm3

This solution is deposited on paper, at a rate of 2 g per m2 and dried.

By exposure to ultraviolet rays under a transparent positive original, then heating at 140 ° C for 20 s, a positive blue image of the original is obtained.

Example 5:

The following composition is prepared:

- naphthyldiphenylurethane 10 g

- 4, diazo 2-5 dibutoxyphenylmorpholine 20 g

- citric acid 10 g

- ethylene glycol 10 ml

- methyl ethyl ketone 11

This composition is then deposited on a paper support, at a rate of 20 cm3 / cm2, then dried.

After exposure to a positive, the different samples are developed with one of the following solutions, using a roller developer of the semi-wet machine type:

- 10% by weight aqueous sodium hydroxide solution,

- 20% aqueous ethanolamine solution,

- 80% aqueous triethanolamine solution,

- 5% aqueous triethylenediamine solution.

In these four cases, a blue image of excellent quality is obtained.

Example 6:

A material such as that obtained in Example 5 is used. After exposure to a positive and development in contact with the ammonia vapors of a diazo machine, a copy of excellent quality is also obtained.

Example 7:

The following composition is prepared:

- p-diethylaminobenzenediazoniumborofluoride 10 g

- pyrogallol blocked with toluenediisocyanate 10 g

- citric acid 5 g

- ethanol 500 ml

- thiourea 5 g

After coating on a paper support, then exposure through a positive, the copy is developed using a liquid such as:

- ■ normal ammonia solution (IN),

- pure piperidine,

- Pure N-methylmorpholine.

An excellent quality brown image is obtained at room temperature. In order to dry the material, it can be heated without the quality of the copy being improved.

Example 8:

The composition of Example 7 is repeated, coated in the same manner on a paper support, then exposed through a positive. After development in an aqueous solution of ammonium hydrogen carbonate at 20%, the support is dried at a temperature greater than or equal to 50 ° C. and a copy of excellent quality is obtained.

Example 9:

To the composition of Example 1, 0.05 g of dilauryl-dibutyltin is added. After coating on the paper support, the same colored trace is obtained, but at a temperature of 120 ° C.

Example 10:

In the composition of Example 2, 1 g of lead octoate is added. A colored trace of the same intensity is obtained as in Example 2 at a temperature of 140 ° C.

Example 11:

On the material of Example 3, an overcoat composed of:

- Rhodoviol 4-125 (polyvinyl alcohol from the company Rhône-Poulenc) at 10% in water 5 g

- triethylenediamine 0.5 g We obtain a dark brown colored trace of the same intensity

as in Example 3, with a thermal head brought to a temperature of 100 ° C.

Example 12:

On the material of Example 4, an overcoat consisting of a 5% by weight solution of ammonium carbonate in polyvinyl alcohol is deposited.

After exposure to a translucent original, the material is developed at a temperature of 120 ° C and a trace of blue color is obtained.

Example 13:

The material obtained in Example 4 is taken. The following dispersion is placed on the back of it, at a rate of 10 g / m2:

- ground borax 5 g

- ground ammonium fluorosilicate 15 g

- Rhodopas H (polyvinyl acetate from the company Rhône-Poulenc) 5 g

- toluene 30 ml

The exposure to ultraviolet rays is carried out through a translucent original, then heating to 110 ° C. for approximately 10 s. We get a positive blue image of the original.

The invention is applicable to all recording and reproduction methods using phenols, when it is desired to generate it in situ, by unblocking the urethane present in the sensitive layer.

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R

Claims (12)

618,640 1. Recording or reproduction material comprising a support coated with a sensitive layer containing a chromogenic compound capable of reacting with a phenol or a naphthol to give rise to a colored trace, characterized in that the sensitive layer also contains a urethane capable of generating in situ a phenol or a naphthol, said urethane being derived from an isocyanate and from a benzene or naphthalene mono-, di- or triphenol in which the aromatic nucleus is or is not substituted, with the exception 2,3-bis (alkylcarbamoyloxy) naphthalenes of formula: GOLD OY in which R represents an alkylcarbamoyl group in which the alkyl chain contains from 1 to 4 carbon atoms and Y represents a hydrogen atom or the group R. 2. Material according to claim 1, characterized in that the chromogenic compound is an indolinic or benzo-thiazolic spiropyran, a derivative of triphenylmethane, a ferric salt or a diazo compound. 2 3. Material according to one of claims 1 or 2, characterized in that the urethane is a derivative of mono- or dihydroxy-naphthalene or ß-hydroxynaphthoi'que acid. 4. Material according to one of claims 1 or 2, characterized in that the urethane is a derivative of phenylisocyanate, toluylene diisocyanate, naphthylene 1,5-diisocyanate, 4,4'-diphenylmethane diisocyanate or hexamethylene 1,6-diisocyanate. 5. Material according to one of claims 1 to 4, characterized in that the sensitive layer also contains a binder chosen from polyvinyl alcohols, polyvinyl esters, acrylic esters and homo- or copolymers based on polyvinyl chloride. 6. Material according to one of claims 1 to 4, characterized in that the sensitive layer additionally contains an aliphatic alcohol, a hydroxylated polyether or a hydroxylated polyester, alone or as a mixture. 7. Material according to one of claims 1 to 4, characterized in that the sensitive layer further comprises a decomposition catalyst for phenylurethane capable of lowering the decomposition temperature thereof. 8. Material according to claim 7, characterized in that the decomposition catalyst is chosen from: - ammonia, - mineral bases, for example soda or potash, - the aliphatic amines, preferably the aliphatic tertiary amines of general formula: / Rl N — R2 with R1; R2, R3 having from 1 to 10 carbon atoms, R3 Cyclic aliphatic tertiary polyamines, for example hexamethylenetetramine or triethylenediamine, - hydroxylated amines, for example mono-, di- or trietha-nolamine, 2-amino-1-butanol or tri (hydroxymethyl) ami-nomethane, - organic or mineral ammonium salts, for example carbonates, hydrogen carbonates, formates, oxalates or benzoates, - morpholine and its derivatives, for example N-methylmorpho-line, 2,6-dimethylmorpholine or N-aminoethyl morpholine, - metallic salts of organic acids, the metals which can be used are preferably tin, calcium, lead, zinc or aluminum, the organic acid having from 3 to 18 carbon atoms, preferably from 5 to 10, - organotin salts, - products or pairs of products producing ammonia when heated, preferably: - urea, thiourea and their derivatives, - ammonium salts which can be decomposed by heat, for example ammonium carbonate or ammonium benzoate, - the pairs of products which, by reaction to heat, produce ammonia, for example, the pairs consisting of ammonium salt of a strong acid and metallic compound. 9. Use of the recording or reproducing material according to claim 1, characterized in that it is subjected to a contribution of thermal energy which breaks down the urethane to give rise to a phenol or a naphthol reacting with the chromogenic compound. and thus generate the colored trace. 10. Use according to claim 9, characterized in that said material is brought into contact with a fluid capable of breaking down the urethane to give rise to a phenol. 11. Use according to claim 10, characterized in that the fluid is chosen from: - ammonia or ammonia, - mineral bases, for example soda or potash, - the aliphatic amines, preferably the aliphatic tertiary amines of general formula: / Rl N — R2 with Ri, R-2, R-3 having from 1 to 10 carbon atoms, R3 Cyclic aliphatic tertiary polyamines, for example hexamethylenetetramine or triethylenediamine, - hydroxylated amines, for example mono-, di- or trietha-nolamine, 2-amino-1-butanol or tri (hydroxymethyl) ami-nomethane, - organic or mineral ammonium salts, for example carbonates, hydrogen carbonates, formates, oxalates or benzoates, - Morpholine and its derivatives, for example N-methylmorpho-line, 2,6-dimethylmorpholine or N-aminoethylmorpho-line. 12. Use according to one of claims 10 or 11, characterized in that the material is then heated to a temperature above 40 ° C.