CS209139B1 - Diazographic material with red grain - Google Patents

Description

(54) Diazographic material with red drawing.

The present invention relates to a reddish diazographic material for ammoniacal or liquid induction which provides final mixed azo dyes of good stability to water and alkalis and is characterized by the use of largely cheap and available raw materials.

It is well known to prepare reddish diazographic materials for ammoniacal or liquid induction on paper or other suitable support using light-sensitive diazo compounds derived from simple or substituted p-phenylenediamine derivatives suitably stabilized, preferably with a suitable heterocyclic moiety. It is also known to use diazo compounds derived from naphtho sulfonic anhydrides, diphenylamines and the like. In order to achieve an acceptable red tone, the use of floroglucine or its resorcinol mixture or floroglucides directly as coloring agents is particularly suitable for the latter. Very acceptable drawings can be achieved by the application of coupling components derived from single or higher substituted resorcylic acid derivatives or halo gene resorcylic in the form of, for example, heterocyclic amides, amides, substituted amides, ureides. The latter compounds provide mostly red shades in pastel red or reddish brown.

The disadvantage of such materials which employ more complex substituted resorcylic acid amides is the low solubility of these color-forming components, which leads to premature crystallization of emulsions and solutions, or to uneven diazographic coatings on paper or other diazomaterials. increasing the solubility of said compounds. Some improvement can be achieved by adding, for example, glycerin, ethylene glycol or some. of sugars. For example, dipropylene glycol or some alkaloids may be advantageously used to ensure solubility, but on the other hand they are difficult to access, energy-intensive, and generally expensive.

A diazographic material having a red pattern for ammoniacal or liquid has now been found on a paper backing providing a brilliant red or reddish-brown pattern on a colorless background where the low solubility of color-forming is eliminated. components and thus the entire diazographic assembly of said material. .. ..

SUMMARY OF THE INVENTION The present invention relates to a reddish diazographic material for ammoniacal or liquid induction comprising a lignin-free paper substrate having a weight of 20 to 200 g / m, which is provided with a pre-separation, barrier or anti-barrier layer on a dry weight basis of 0.1 up to 25 g / m and a diazographic composition comprising 0.3 to 8.5 percent of a diazo compound derived from simple or substituted p-phenylenediamine derivatives, preferably dialkylamino, hydroxyalkylamino, 2,5 dialkoxy-morpholino or 3-alkyl or alkoxy-pyrrolidino - p-phenylenediamine derivatives, with the addition of 0.5-9.2 percent of 3,5-resorcylic acid or 4-bromo-3,5-resorcylic acid methyl- or ethanolamide and 0.1-10.7 percent of the caffeine extraction residue from coffee beans, calculated on the dry matter, and buffering, metallizing or stabilizing substances, wetting agents, optical bleaches or plasticizers. The term 'residue from caffeine extraction from coffee beans' refers to a waste liquor consisting of 78 to 98% of caffeine, fatty oil residues and waxes containing predominantly 5-hydroxy-triptamide carboxylic acids in the dry matter. the remainder still contain traces of pyridine or its derivatives, furfurol, phenols, vinylcarbamide and generally trace tars. This waste can be used according to the invention in the form of a solution or suspension of any concentration, optionally in the form of a solid evaporator. It was found that residual proportions accompanying caffeine have no adverse effect on the level of material and its final quality parameters, on the contrary, an increased proportion of wax parts deepens the color tone of the resulting drawing.

Example 1

Barrier layer

Aqueous dispersion of vinyl acetate-butyl acrylate copolymers

C ratio 4: 1) with a dry matter content of 48% 750 ml

Water deionized or distilled 1200 ml

Silica with particle size up to 15 µm 98 g

O

A suspension is prepared and applied in a conventional manner to a paper substrate in an amount of 2.2 g / m 2, calculated on dry weight.

Example 2

Sensitive diazographic layer

Water deionized or distilled 400 ml Citric acid 20 g Thiourea 22 g Urea 20 g Zinc chloride 9 g Diethylene glycol 20 g Water deionized or distilled 300 ml Caffeine extraction residue from coffee beans (conversion to dry matter) θ g 4-Bromo-3,5-resorcylic acid methylamide 10 g

After dissolution, solution I and II are reduced, made up to 900 ml with deionized or distilled water and 4-diazo-2,5-diethoxyphenylmorpholine added. 1/2 ZnC ^ 10g

After dissolution, the sensitive layer is poured onto the paper in a conventional manner and dried.

Example 3

Sensitive diazographic layer.

I. Water deionized or distilled 400 ml,

Citric acid 12 g

Tartaric acid 10 g

Thiourea 18 g

Urea 12 g

Zinc chloride 12 g

Sodium chloride 7 g

Polyethylene glycol m.h. 1,500.6 g

II. Water deionized or distilled 300 ml

Caffeine extraction residue from coffee beans (calculated on dry matter) 12 g

3,5-Resorcylic acid ethanolamide 14 g

After dissolution, solution I and II are reduced, made up to 900 ml with deionized or distilled water and 4-diazo-N-ethyl-N- ' -hydroxyethylaniline is added. 1/2 ZnClg 14g.

After dissolution, the sensitive layer is poured onto the paper in the usual manner and dried.

The advantages of reddispersed diazographic materials for the ammoniacal or liquid development according to the present invention are higher drawing qualities, very good light-sensitivity, contrast and stability, and especially the use of the waste product which, in addition to economic aspects, is beneficial for environmental improvement. after extraction of caffeine from coffee beans it was discharged into waste water.

The use of reddish diazographic materials for the ammoniacal or liquid induction according to the invention is in the whole field of reprography within the national economy, in particular in industrial fields, in the field of technical documentation and state information policy.

Claims (1)

SCOPE OF THE INVENTION Diazographic material with red pattern for ammoniacal or liquid induction, characterized in that it contains a lignin-free paper backing weighing 20 to 200 g / m, which is provided with a pre-separation, barrier or anti-barrier layer weighing 0.1 to 25 g dry matter. and a diazographic assembly comprising 0.3 to 8.5 percent of the diazo compound derived from simple or substituted p-phenylenediamine derivatives, preferably dialkylamino, hydroxyalkylamino, 2,5-dialkoxy-morpholinone or 3-alkyl or alkoxy- pyrrolidino-p-phenylenediamine derivatives with the addition of 0.5 to 9.2 percent of 3,5-resorcylic acid or 4-bromo-3,5-resorcylic acid methyl or ethanolamide and 0.1 to 10.7 percent of the caffeine extraction residue of coffee beans calculated on the dry matter, which contains 78 to 98 percent caffeine and residues of fatty oils and waxes, containing predominantly 5-hydroxy-triptamide carboxylic acids, and possibly traces of p yridine or derivatives thereof, furfurol, phenols, vinylcarhamide and trace tars.