CS206396B1 - Sandwich diazographic material - Google Patents

Description

The invention relates to a sandwich diazographic material on a paper support provided with a light-sensitive diazographic assembly for ammoniacal or liquid induction with pre-preparation or pseudo-pre-preparation on one or more barrier layers.

Sandwich diazographic material is a material intended for making copies from translucent backing pads by contact copying or optical transmission (magnification eg from microfilms).

After exposure of this material to ultraviolet radiation and after induction of either ammonia or liquid developer according to the type of material, a light-stable azo dye is formed on the unexposed surfaces by the coupling reaction of the active and passive components. This material can be processed on equipment intended for processing common diazographic materials or copied by original or contacted or enlarged and evoked either by ammonia vapors or by uniformly applying a liquid developer to the surface of the material (cotton wool, etc.).

The diazographic material generally consists of a paper support on which a suitable diazographic assembly is applied. In general, however, toppings are used for the so-called prepreparation, which is intended to level the paper surface and thereby increase the saturation and sharpness of the diazographic copy. In some cases, the prepreparation is directly combined with a sensitive diazographic assembly. This method is very often used for preparing semi-dry papers.

In practice, neither of the two forms of treatment can usually be considered sufficient if the raw paper backing does not exhibit sufficiently high quality parameters, is non-standard or exhibits, for example, high water absorption. In such a case, it was usually necessary to arrange the custom paper backing directly at the raw paper manufacturer and there are no known cases that the manufacturer of photosensitive diazographic materials would do so. The actual treatment of the raw paper, if considered by the manufacturer of diazographic materials, encounters numerous problems of production and capacity character, eg the current state of irrigation technology, which usually has at most 3 casting sites. The treatment of raw paper at the diazographic manufacturer presents further problems in the need to complexly combine conventional casting and emulsion technologies not only in relation to the quality and standard of icing, but also

206 396 especially to the complex relationships of the internal reactions of the substances used in the overall process as well as to the actual stabilization of the finished product. In essence, no method is known to be used by the manufacturer of photosensitive diazographic materials in an attempt to make separate treatments of lower quality papers in order to enhance their quality needed for glazing diazographic assemblies.

A sandwich diazographic material has now been found, where the sandwich arrangement of the individual layers and protective barriers substantially ensures the treatment of the paper backing and fundamentally changes commonly used methodologies for the production of diazographic materials and in conjunction with the subject of a lower quality than is common in this field and generally improves the quality of diazographic materials.

The above-mentioned drawbacks have no sandwich diazographic material according to the invention, characterized in that it comprises a lignin-free paper substrate having a basis weight of 20-200 g / m 2, on which a barrier layer having a basis weight of 0 is applied on one or both sides. 5-38 g / m 2, consisting of a filler selected from the group consisting of silica, silicates, zinc oxide, alumina, titanium dioxide, harium sulfate, talk, kaolin and starch with a mean particle size of 0.01 µm to 50 µm and a binder from the group consisting of polymers, copolymers or mixtures of vinyl acetate, styrene, butadiene, acrylonitrile, vinylpyrrolidone, acrylic acid, methacrylic acid, their esters, amides, alkylsubstituted and N-alkylsubstituted esters and amides, including polymers and copolymers post-crosslinked, vinyl alcohol, vinyl chloride, vinylidene chloride, ethylene, maleic acid, their esters, cellulose derivatives, h The composition of the present invention relates to cellulose derivatives, gelatin, modified gelatin, polydextrans, and substances which, upon drying, are capable of forming solid resilient films, wherein the dry barrier layer has a mass per unit area of 0.5-38 g / m 2 on which a photosensitive diazographic assembly is applied.

The sandwich diazographic material may have components of the diazographic assembly partially dislocated in one or both of the barrier layers.

The sandwich diazographic material may have a paper backing provided on one side that throws them for the photosensitive diazographic layer, a barrier layer controlling the penetration of the counterparty.

The advantage of the sandwich diazographic material according to the invention is the high resistance to water penetration into the paper substrate, the possibility of its regulation on both sides of the material and the possibility of using pads with lower quality parameters than usual for diazographic materials. higher Stock stability.

It is not contrary to the invention to use other than diazography of conventional paper substrates, eg high penetration pads, uneven eg rough or too smooth surfaces, or pads whose chemical properties in immediate contact react undesirably with the components of the diazographic assembly or its degradation products. The object of our invention is a sandwich material which, by its nature and composition, largely eliminates or completely removes the effect of said deficiencies.

According to the invention it is also possible to technologically and physically-chemically treat one, the other or both barrier layers with theologically active substances, for example substances increasing or decreasing the penetration of one or the other side, further substances crosslinking the used polymeric binders to obtain antibiotic. formed from one side of the barrier layer, which by its nature acts as a barrier to further penetration applied from the other side,

In the formation of the sandwich diazographic material according to our invention, a purposeful choice of the individual components is necessary which, due to the possible chemical reactions, is quite complex and must satisfy different conditions which depend on each other. E.g. the paper backing must be provided with one or more hydrophobic barriers which substantially reduce water absorption, but must be sufficiently wettable so that other hydrophilic layers, interlayers and assemblies can be applied directly, providing sufficient consistency in dry and wet conditions stability. The light-sensitive diazographic assembly must be optimally concentrated in order to achieve the desired light transmittance and evolving properties after frosting and drying.

. The barrier layers or other possible interlayers and assemblies, or the actual diazographic assembly, must not contain any substances which have reacted negatively with each other and impair the durability of the article.

According to our invention, the paper backing is provided with a single or double-sided barrier layer or double-sided barrier layers of different composition or one side with a barrier layer and the other side with a anti-twist layer.

The barrier layer is based on a film-forming binder. The binders used are solutions, emulsions, suspensions or dispersions, preferably aqueous dispersions of polymers, copolymers or mixtures of vinyl acetate, styrene, butadiene, acrylonitrile, acrylic acid, methacrylic acid, their esters, amides, alkyl- substituted amides, esters, N-alkyl-substituted esters including polymers and copolymers. additionally crosslinked, vinyl alcohol, vinyl chloride, vinylidene chloride, ethylene, maleic acid, their esters, cellulose derivatives, saponified cellulose derivatives, gelatin, modified gelatin, polydextrans and the like.

Preferably, when using aqueous dispersions of polymers and copolymers with vinyl acetate, additional crosslinking at a higher temperature is used, passing through the drying path of the casting machine using water-soluble modified condensation products of urea, dimethyl-ol-melamine, hexamethyl-ol. melamine, dimethyl-ol-tetramethoxy-methylmelamine, preferably hexamethoxy-methyl-melamine, or less suitable, such as paraformadehyd or glyoxal. As acidic catalysts for crosslinking, organic or inorganic acids of their salts can be used, e.g. hydrochloric, sulfuric, formic, acetic, benzenesulfonic, p-toluenesulfonic, ammonium chloride, ammonium sulfate, aluminum sulfate and the like.

. In addition to film-forming binders, it is advantageous to use certain fillers either individually or in mixtures for forming the barrier layer. The fillers used are kaolin, talc, barium sulphate, titanium dioxide, alumina, zinc, silicates, silicon dioxide, preferably silicon dioxide, primarily from the flux in the production of metallic silicon, starches and generally substances commonly used as medium fillers. particle sizes 0.01 - 50 microns.

The ratio of binder to filler is dependent on the quality parameters of the paper backing and the overall composition of the sandwich, and is in a percentage composition of 1:99 to 100: 0, preferably 20: 80 to 40:60. The use of fillers in the barrier layer has a positive effect on the density and brilliance of the resulting azo dye.

,,, 2 The application of the barrier layer is in the range of 0.5-38 g / m

preferably 2-10 g / m 2.

According to our invention, a hydrophilic palzographic assembly is applied to the barrier layer, preferably with further addition of a film-forming binder or a film-forming binder with fillers in the form of a pseudopreparation.

It is not contrary to the invention to partially subdivide one or more substance-sensitive diazo graphic assemblies into further layers and interlayers, preferably into a barrier layer. Advantageously, buffering, reducing, stabilizing, antihalatory, passive and active components and metallizing agents, which in some cases act by their metal ions as a crosslinker of the polymeric film-forming binders, can be separated between the sensitive and barrier layers.

The hydrophilic photosensitive diazographic assembly comprises 0.3-5% of diazo compounds or mixtures of diazo compounds based on single or substituted p-phenylenediamine derivatives, preferably 4-diazo-dialkyl or 4-diazo-alkyl-alkoxy-p-phenylenediamine or the corresponding compounds with heterocyclic moieties, such as piperidine, pyrrolidine, morpholine, diazo compounds substituted in the 2,5-position on the nucleus by alkyl or alkoxy or halogen, diazo compounds substituted in the branched chain on the tertiary nitrogen, diazo compounds having a 4-position substituted tertiary amino group , sec. acylamino, sec. acylamino, phenyl or mercapto and at one or two positions halogen, alkyl, alkoxy, phenoxy or tert. an acylamino group or a combination of these substituents or diazo compounds derived from simple, optionally substituted diphenylamines. As coupling agents, 0.4-6 percent of a color-forming coupling component or mixtures thereof capable of providing neutral mixed azo dyes are used. Depending on the desired color of the drawing, for example, acetylacetyllated derivatives of aniline, benzamide, toluidine, anisidine, or polyhydroxyphenols and their substituted derivatives of ethylenediamine-bis-acetoacetamide, alpha or beta resorcylic acid derivatives, single or substituted hydroxycaronic acid amides, preferably then morpholinopropylamide, diethanolamide, piperidide or piperazide of acids or components derived from hydroxy or polyhydroxynaphthalene or the corresponding sulfonic acids or their salts, preferably e.g. 2-oxy-3-naphthoic acid beta-aminoethylamide and other components for tinting the assembly such as resorcin and floroglucin. In the case of liquid-induced diazographic materials, the copolymers may be distributed between the layer and the developer, or dosed only into the developer, and absent in the layer. Furthermore, the photosensitive diazographic assembly contains in the diazography common buffering substances, reducing, antihalation, stabilizers, metallizing, surface active, plasticizers, etc.

The diazographic light-sensitive assembly may advantageously be supplemented with an additional film-forming binder in an amount of 0.5 - 40 percent. The polymeric binders used are preferably the same or similar to the barrier layer, as well as the same or similar fillers, preferably starches with a mean particle size of up to 15 microns.

In the case where so-called anti-barriers are used, i.e. such a barrier layer which contains penetration-regulating agents on the main topping side, substances having the ability to optimize penetration, preferably zinconylammonium carbonate complexes, are used in the barrier layer. These penetration-regulating substances can be dosed 1 into the barrier layer on the glazing side of the photosensitive assembly or can be poured separately.

It is not contrary to the invention to coat the backsheet with an anti-twist layer comprising, for example, cellulose derivatives, polyvinyl alcohol, metal salts, optical bleaches, surfactants, stabilizers, buffering agents and other substances conventional or possibly anti-twist layers combined with a barrier layer. , possibly with a penetration regulator. Examples of a sandwich arrangement according to the invention:

1) C (D, G) -B-A-B

2) C (D, G) -B-A

3) C (D, G) -A-B

4) C (D, G) -B-A-H

5) C (D, G) -A-1

6) C (D, G) R * B-A-J.

7) C (D, G) -A-K

8) C (D, G) - B - A - K

9) P-E-A-B (H, 1, J, K)

In this scheme, individual capital letters mean:

A Paper Pad

B Barrier layer

C Light-sensitive diazographic set

D Light-sensitive diazographic set with pseudopreparation

E Barrier layer with partial separation of components. photosensitive diazographic assemblies

F Light-sensitive diazographic set with partially divided components into barrier layer

G Light-sensitive diazographic assembly with film-forming binder

H Rear anti-twist layer

I Antibariéra

J Barrier layer plus rear anti-twist

K Barrier plus rear anti-twist plus anti-penetration

The following examples illustrate the individual layers and assemblies of the present invention

Example 1 - barrier layer ml 50% aqueous dispersion of butyl acrylate / methyl methacrylate copolymer ml distilled or deionized water /

The layer is applied in the usual manner to the paper and dried. Quantity 4.3 g / m on dry weight basis.

Example 2 - barrier layer with filler ml 50% aqueous dispersion of ethyl acrylate-styrene copolymer ml water distilled or deionized g SiOg (mean particle size up to 10 µm)

The filler disperses perfectly. The layer is applied in the usual manner.

¹ Coating 5 g / m on dry weight basis.

Example 3 - Back Anti-Twist Layer

120 ml water (distilled or deionized) 6 g polyvinyl alcohol

0.5 g of polyethylene glycol (mol. Wt. 1,500)

r.i g chloride, sodium 0.2g diluent

It is applied in a conventional manner in an amount of 2 g / m @ 2 of dry matter.

Example 4 - penetration regulator

A 20% aqueous suspension of substances is prepared:

(NH ₄ ) ₃ ZrOH (CO ₃ ) ₃ and (NH 4 ZrO (COg) ₂ and this suspension is optionally fed to the layers in an amount of 1%.

In the case of layer coating, where the penetration regulator is separate, the suspension is prepared at 2%. The deposition is dependent on the quality of the paper substrate and is in the range of 0.1 - 20 g / m, calculated on dry weight.

Example 5 - diazographic report  450 ml water (distilled or deionized) 9 g Citric acid 3 g boric acid 8 g thiourea θ g zinc chloride 8g aluminum sulphate 10 g 4-Diazo-N-ethyl-4-oxyethylaniline. l / 2Znd ₂ ⁸ 8 / 2-oxy-3 naphthoic acid ethanolamide

0.5 g wetting agent

Make up to 600 ml with water.

Example 6 - diazographic set with pseudopreparation

To the diazographic assembly of Example 5, a suspension is added:

ml 50% aqueous dispersion of polyvinyl acetate and butyl acrylate 50 ml water deionized 25 g starch rice g SiO (gray particle size up to 10 µm)

After the suspension is added to the diazographic assembly, thorough mixing is performed. The coating and drying are carried out in the usual manner. The deposition is governed by the absorbency of the treated paper backing with the desired sensitivity and brilliance of the diazographic material.

Example 7 - Diasograph set and barrier layer with partially divided components

Example 7a - diazographic set:

450 ml water (distilled or deionized) g 'citric acid 4 g tartaric acid 6 g thionic acid

8. g zinc chloride.

g aluminum sulphate g 4-diazo-2,5-dimethoxyphenyl-morpholine.ZnCl ₂ 1 g. wetting agent

Make up to 600 ml with water.

Example 7b-barrier layer:

400 ml water (distilled or deionized) g citric acid 2 g thiourea6 g 4-bromo-3,5-resorcylic acid 120 g SiC> 2 (mean particle size 10 µm)

100 ml aqueous dispersion of vinyl acetate copolymer and ethyl methacrylate

Claims (3)

Sandwich diazographic material, characterized in that it comprises a lignin-free paper backing having a surface weight of 20 to 200 g / m 2, on which one or both sides of a 2 - 0.5 g / m 2 barrier layer consisting of a filler is applied from the group consisting of silica, silicates, zinc oxide, aluminum oxide, titanium dioxide, barium sulfate, talk, kaolin and starch, with a mean particle size of 0.01 and 50 µm and a binder selected from the group consisting of polymers, copolymers or mixtures of vinyl acetate, styrene, butadiene, acrylonitrile, vinylpyrrolidone, acrylic acid, methacrylic acid, their esters, amides, alkyl-substituted and N-alkyl substituted esters and amides, including polymers and copolymers additionally crosslinked, vinyl alcohol, vinyl chloride, vinylidene chloride, ethylene, maleic acid, its esters, cellulose derivatives, hydrolyzed cellulose derivatives, gelatin modified gelatin, polydextrans, and fabrics which upon drying are capable of forming rigid, resilient films onto which a light-sensitive diazographic assembly is applied. 2. The composite diazographic material of claim 1, wherein the components of the diazographic assembly may be partially dislocated in one or both of the barrier layers. 3. Sandwich diazographic material according to claim 1 or 2, characterized in that the paper backing can be provided with a barrier layer on the base for the photosensitive diazographic layer, the other side of the paper backing being provided with an anti-lateral penetration-controlling layer.