NO138049B - PROCEDURES FOR DIAZO COPYING USING SMOODS DEVELOPERS AND AMINIDE DEVELOPERS FOR SUCH USES - Google Patents

Description

The present invention relates to a method for reproducing an original on a two-component diazotype copying material and a developing liquid for use in the method where the active component is an organic amine. More specifically, the invention relates to a developing liquid, which can be used under conditions whereby small amounts of the liquid are distributed over the latent-image-bearing surface of a two-component material of the diazo type.

Diazotype reproduction processes, whereby a two-component diazotype material is developed by applying a small amount of developing fluid, usually not exceeding 3 g per m of the surface that carries the latent image is described in US Patent No. 3,446,620. This known technique, which provides a dry copy directly from a developing step, is carried out by transferring a regular amount of the 3en concentrated developing solution, which contains an aliphatic amine, to a two-component diazo type material. Said technique requires a developing zone through which the exposed diazotype paper is fed, whereby the regulated minor amount of liquid is directly applied to the surface bearing a latent image of diazotype to effectively develop the azo color image, and the copy is obtained dry, odorless and ready for use.

The regulated quantities of liquid involve the application of amounts which

does not exceed 3 g developer per m 2 of the image-bearing surface, preferably approx. 0.5 - 2 g/m 2.

The method described in US patent document 3,446,620 can be carried out using a number of different types of devices which are specially adapted to the application of regulated amounts.

Such a device is described in US patent document 3,626,833. It should be noted that with such a developing device the usual routine technique for applying a liquid is not used, but special considerations must be taken into account.

When a liquid developer is applied in an amount of 1 or 2 g/m<2 >surface of the two-component diazo type material, it is necessary that the liquid in the development zone is applied evenly distributed on

such a way that the obtained azo color image exhibits a uniform color density. It has also been shown that the device which applies the regulated amounts develops u-tréettes for s-fcore stresses, and the developer must be distributed evenly over the image-bearing surface.

A device provided with feed rollers, which are specially adapted to carry a regulated amount of liquid and work in combination with a rubber scraper or other wiping means to further regulate the amount of liquid, tends to create strong frictional forces in the development<g>step . The strong frictional stresses in the developing step in turn cause stress on the device's drive mechanism, whereby the drive rollers are brought into irregular motion. This results in a noticeable variation in speed. the paper,

which is to be used in the development, is thus fed through the developing device in the wrong way, and this causes streaks and other irregularities in the copy due to uneven liquid application.

It is a general purpose of the invention to provide an improved liquid developing composition for developing the two-component diazotype material, which enables the application of very small amounts of said liquid so that this is distributed evenly over the surface of the diazotype material.

Another object according to the invention is to provide an improved liquid developing composition for developing two-component diazo-type material, which has the ability to reduce the stresses imposed on a developing device under such conditions whereby less than 3 g of said developing liquid is applied to each m of that surface to the diazotype material which carries the latent images.

It is a particular object of the invention to provide an improved developing liquid composition for developing the two-component diazo-type material by using a concentrated solution of an aliphatic amine and a carboxylic fatty acid to increase the smearing ability of the system, and whereby the uniformity of the application in highly supported.

Said purpose is met with a new developing liquid composition, which consists of 20 - 80% by weight of an active alkaline component, such as an aliphatic amine, a diluent consisting of a polyhydric alcohol, a glycol ether or a monofunctional alcohol, and a carboxylic fatty acid with 15-18 carbon atoms in a proportion of 3-20% by weight.

The following description relates to further details in connection with particularly suitable embodiments of the developer according to the invention.

The alkaline component of the developer may be a compound of the general formula

where R 1 means alkyl, cycloalkyl, alkyl-aryl, alkylol, alkoxy or alkylolalkoxy,

R2 and R3 alkyl, cycloalkyl, alkyl-aryl, alkylol, alkoxy, alkylolalkoxy or hydrogen and where

means a heterocyclic ring, such as morpholine or piperidine. Suitable and according to the invention usable amines are those with the formula

where R and R' mean the same or different alkyl or hydroxyalkyl groups or hydrogen,

X means hydrogen, alkyl or hydroxyalkyl and where n means the number 2, 3 or 4.

The term "alkylol" is the same as hydroxyalkyl and "alkylolalkoxy" is the same as polyol or hydroxyalkyloxyalkyl, which terms are interchangeable.

The alkaline component can be diluted with a compound selected from the group consisting of polyhydric alcohols, a glycol ether, a monofunctional alcohol and water or mixtures thereof. The diluent is present in an amount of 17 - 60% by weight.

The following amines have been found to be particularly suitable when using the present method: monoethanolamine, isopropanolamine, 2-(2-aminoethoxy)ethanol, triethanolamine, diethanolamine, 2-amino-2-methyl-1-propanol, N-methylethanolamine , dimethylethanolamine, hexylamine and cyclohexylamine. Other amines also have the ability

to be able to induce diazo copy, such as P-hydroxyethyltrimethylammonium carbonate, N-aminoethylethanolamine, alkyl-substituted morpholine and piperidine, but these latter are less suitable because they have a noticeable smell, or because they have a tendency to affect the color shades in a harmful direction.

The use of a diluent promotes the spreading or distribution of the developer over the applied surface and thus its wetting. The diluent can also be used to adjust the viscosity of the developing liquid, so that it can easily be made to flow through various lines and up to the iiremkalling zone. If the diluent also exhibits higher volatility than the aliphatic amine, then it has the ability to evaporate from the surface with a drying effect on the thin layer.

The diluent may consist of a polyhydric alcohol, such as hexylene glycol, diethylene glycol, polyethylene glycol, trimethylene glycol, ethylene glycol, propylene glycol, dipropylene glycol, glycerol and glycol ethers, such as ethylene glycol monoethyl ether (Cellosolve), diethylene glycol monoethyl ether, diethylene glycol monomethyl ether, butyl Cellosolve, or a monofunctional alcohol, such as 4-methoxy-4-methyl-pentanol-2 (Pentoxyl), 2-ethylhexanol, cyclohexanol, isooctyl alcohol and hexanol.

It has proven to be advantageous to use such polyhydric • alcohols which are completely combinable with the aliphatic amines, and which do not adversely affect the quality of the copy. Furthermore, polyhydric alcohols, such as hexylene glycol and glycol wood, promote the spreading of the developing liquid.

The technical progress obtained with the invention is represented by the addition of a third component, such as a carboxylic fatty acid with a carbon chain length of 16 - 18 carbon atoms, such as stearic acid, palmitic acid, cis-9-octadecenoic acid, cis,cis-9,12-octadecadienoic acid or cis, cis,cis-9,12,15-octadecatrienoic acid,

in a quantity ratio of 3 - 20% by weight.

One should notice that the amount of carboxylic acid,

which must be added to developing compositions to reduce the frictional forces in the developing system, may depend on the concentration of organic amine. It has been shown that at the higher concentrations it may be necessary to heat the developer to a temperature above room temperature in order to keep the carboxylic acid component in solution.

The invention is illustrated in more detail by means of the following examples, whereby occurring percentages refer to the weight, when not stated otherwise. It should be noted that the combination of "fatty alkanolamine with a carboxylic fatty acid gives the alkanolamine salt. Thus, for example, stearic acid gives the stearate salt of monoethanolamine.

EXAMPLE 1

The components are mixed in a mixing vessel until a uniform solution is obtained. The solution is supplied to the developer part in a remote development device, and which is described in the simultaneously pending US patent application No. 831,685.

EXAMPLE 2

EXAMPLE 3 EXAMPLE 4

EXAMPLE 5

EXAMPLE 6 EXAMPLE 7 EXAMPLE 8 EXAMPLE 9

"Kr"/

EXAMPLE IO

EXAMPLE 11

EXAMPLE 12

EXAMPLE 13

In each of the developing solutions described above

entailed the addition of the carboxylic fatty acid that

reversible smbre property, whereby in the used developing

the device could provide a uniform distribution of the liquid over the surface used for development in a quantity

ratio of 0.5 - 3 g per m 2 and this without the drive mechanism being subjected to any harmful stress, the advancement of the copy web through the developing station was smooth and safe,

and one could not notice any such twitching or other irregularity-

relative movement that can be observed when using developing

liquids that do not contain carboxylic fatty acids, whereby streaks and uneven azo dye formation on the web surface are obtained.

Claims (2)

1. Method for reproducing an original on a two-component diazotype copying material, which involves (a) exposing the copying material to an actinic radiation pattern that preserves the light and dark areas of the original, thereby creating a latent image, (b) feeding into a developing zone a regulated amount of alkaline developer consisting of at least 20% by weight of an organic amine selected from morpholine, piperidine, (lower alkyl)-morpholine, (lower alkyl)-piperidine and an amine of the formula where R^ is alkyl, cycloalkyl, alkyl-aryl, alkylol, alkoxy or alkylolalkoxy and where R* ~ and R 3 are alkyl, cycloalkyl, alkyl-aryl, alkylol, alkoxy, alkylolalkoxy or hydrogen dissolved in a diluent consisting of a polyhydric alcohol , a glycol ether or a monohydric alcohol, containing at least 6 carbon atoms, (c) passes the copying material through the said zone and applies the liquid under pressure in an amount not exceeding 3.0 g/m<2 >on the surface involving latent images and whereby the amount of liquid is spread evenly and uniformly over said surface at a temperature at which the liquid does not essentially evaporate, whereby an azo color image is momentarily formed on said surface and the copy is taken out from said zone in a dry state and ready for use, characterized by the use of a developer containing 17 - 60% by weight diluent and 3 - 20% by weight fatty acid with 16 - 18 carbon atoms. 2. Developing liquid for use in the method according to claim 1 comprising at least 20% by weight of a liquid organic amine selected from morpholine, piperidine, alkylamorpholine, alkylpiperidine and an amine with the formula where R^ is alkyl, cycloalkyl, alkyl-aryl, alkylol, alkoxy or alkylolalkoxy and where R2 and R^ are alkyl, cycloalkyl, alkylaryl, alkylol, alkoxy, alkylolalkoxy or hydrogen dissolved in a diluent consisting of a polyhydric alcohol, a glycol ether or a monohydric alcohol with at least 6 carbon atoms, characterized in that the liquid contains 17 - 60% by weight diluent and 3 - 20% by weight fatty acid with 16 - 18 carbon atoms.