The Primuline Or Diazotype Process
Primuline, discovered in 1887 by Mr. A. G. Green, an English chemist, is a
dye of a primrose color, possessing a great affinity for cotton fibers, to
which it is readily fixed by simply immersing the material for a few
moments in a hot solution of the dye. If the material so dyed be placed
in an acidified solution of nitrous oxide, the primuline is diazotized,
forming a derivative compound of a deeper color, which fades in the lig
and which in presence of amines and phenols gives rise to a variety of
dyes whose color depends on the reagent employed, while, when acted on by
light, the resulting compound is entirely deprived of this property. In
other words, the diazotized primuline acts as a mordant only when not
altered by the luminous action.
The chemical change light effects in the diazotized primuline is not well
known. It is pretty certain, however, that nitrogen is set free, for if
gelatine imbued with primuline be immersed in water after insulation,
nitrogen is set free and can be collected as usual in a tub filled with
water and inverted on the substance.
By itself diazotized primuline is slowly influenced by light, but quickly
acted on in presence of organic substances. It is more sensitive when
applied on cotton or paper than on wool, silk, linen, and such organic
compounds as gelatine, albumen, caseine, starch, etc. Its sensitiveness
is about one-tenth less with gelatine than with cotton.
The sensitiveness of diazotized primuline to light, when united to organic
substances and the different colors which can be obtained with the
unaltered compound, have given rise to an interesting printing method, the
invention of Messrs. A. G. Green, C. F. Cross, and E. J. Bevan, which
yields positive impressions from positive cliches. The manipulations of
the process are simple:
In a certain quantity of rain water, kept at nearly the boiling
temperature by an alcohol lamp placed under the vessel, dissolve per cent.
2 parts of commercial primuline, and in this immerse, by means of a glass
rod, some pieces of calico--free from dressing--turning them over several
times during the immersion. When the fibers are well imbued, which
requires from four to five minutes, remove the calico with the glass rod
and rinse it thoroughly in water. This done, wring out the superfluous
liquid as much as possible, and, finally, immerse each piece separately in
a solution of
Sodium nitrite, 7 parts
commercial
Hydrochloric acid, 16 parts
commercial
Water 100 parts
After turning the pieces of calico two or three times over, they are
rinsed to eliminate the acid, then drained and placed between sheets of
blotting paper to dry. All this, except the impregnation with primuline,
should be done in the dark room.
As said above, primuline is transformed by nitrous oxide into a diazotized
compound, and consequently the material is now susceptible of being acted
on by light. It does not keep, and should be exposed, etc., soon after
its preparation.
Paper is impregnated with primuline either by floating or brushing. The
best results are obtained with paper previously sized with arrowroot or
gelatine in order to keep the image entirely on the surface of the paper.
Linen, silk and wool are treated as calico.
The cliches should be positive to obtain positive expressions and somewhat
more opaque than those employed in the processes before described, else
vigor and intensity could not be obtained. Here we must state that the
primuline process seems to be better adapted for the reproductions of
drawings, such as made for the black process, and of opaque photo-cliches
in lines, or white and black, than for printing in half tone.
When the material to print upon is thick and wholly impregnated with
diazotized primuline, it is advisable, since the insulation could not be
prolonged to effect the change through, to expose the back of the material
for a certain but short period in order to clear it. This is especially
advantageous when the cliche is not of good intensity.
During the exposure, which varies from 30 seconds to 10 minutes and more
by a dull light, the progresses of the luminous action is seen by the
bleaching of the material which assumes a dingy coloration. But in order
to ascertain when the decomposition is complete on the ground of the
image, it is well to use tests as in the cyanofer process, dipping one
of them in the developer from time to time.
The developers are compounded as follows:
FOR RED.
Beta-naphthol 4 parts
Caustic potassa 6 parts
Water 500 parts
Rub the alkali and the naphthol with a little water in a mortar and add
the remainder of the water.
FOR ORANGE.
Resorcin 3 parts
Water 500 parts
When dissolved add
Caustic potassa 5 parts
FOR YELLOW.
Carbolic acid, cryst 5 parts
Water 500 parts
FOR PURPLE.
Naphthylamine 6 parts
Hydrochloric acid, in 6 parts
volume
Mix in a mortar, then add
Water 500 parts
FOR BLACK.
Eikonogen, white crystals 6 parts
Water 500 parts
Pulverize the eikonogen, add the water and, at the same time, the material
on its removal from the printing frame, and keep in motion until the
development is effected.
FOR BROWN.
Pyrogallol 5 parts
Water 500 parts
After the development, which requires but a few moments, it suffices to
wash the material to fix the image by eliminating the soluble compounds.
However, for purple the material should be passed in a dilute solution of
tartaric acid and not washed afterwards; it should remain acid.
When it is desirable to obtain an impression in several colors, the
various developers are thickened with starch, then locally applied with a
brush on the image, which is always visible after exposure.
For printing on wood, glass and porcelain, see further on.
More
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A Poitevin's Process 1870
"I use a paper prepared with iron sesquioxide rendered sensitive to light by tartaric or, better, citric acid in concentrated solution. This paper, after desiccation and exposure to light, possesses the property of reducing the solution of silver... Artigues' Process
The Artigues process, so called, is, without any doubt, the best to be employed for the reproduction of plans and drawings in lines. It is simple, expeditious, and yields black impressions on a very pure white ground which are absolutely permanen... Causes Of Failures
The images are veiled. This defect may result from various causes, viz.: 1st. The stock ferric oxalate solution is impaired by a partial reduction of the ferric salt into ferrous oxalate. The solution should be preserved in an o... Choice Of Paper Sizing
In all the photographic processes by precipitation of metallic oxides the quality of the paper has a great influence on the results. When the paper is not well sized and not well calendered, the sensitizing solution is absorbed, instead of simply ... Cj Burnett's Process 1857
"A capital process for many purposes," says Mr. Burnett, "is to float or steep the paper in a mixed solution of bichromate of potash and sulphate of copper, as for Hunt's chromotype process.(36) I have mixed gelatine, or occasionally grape sugar, ... De La Blanchere's Process 1858
Uranium nitrate 25 parts Distilled water 100 parts Filter the solution and keep it in the dark. The paper should be sized with a gelatine solution at 5 per 100 of water, and, when dry, kept in the dark.(40) It is sensitized by floating fi... Dr Jb Obernetter's Process 1863
Copper chloride 100 parts Ferric chloride, sol. sp. 13 parts gr. 1.5 Hydrochloric acid, conc. 12 parts C. P. Water 1,000 parts Float the paper on this solution for about two minutes and hang it up to dr... Dr Tl Phipson's Process 1861
Take a solution of perchloride of iron and, having precipitated the peroxide with ammonia, collect the precipitate on a filter and wash it with boiling water. Add the precipitate in excess to a warm solution of oxalic acid. A beautiful emerald g... Godefroy's Process 1858
Float the paper upon the following solution for three minutes and hang it up to dry: Uranium nitrate 30 to 60 parts Silver nitrate 8 parts Water 100 parts (39) The sensitiveness increases in proportion to the quantity of ... Graphotypy
This process consists in converting a cliche in half tones into one in lines, which can be directly printed on paper, or impressed, by means of an ink transfer made as explained before, on a stone, or on a zinc or copper plate for etching in relie... Guarbassi's Process 1867
The paper is floated in the dark for four or five minutes on a saturated solution of bichromate of potash. When dry, it is printed a little longer than for silver prints and afterwards floated, face upwards, on a water bath until all the unaltere... H Cooper's Process 1865
PREPARATION OF THE PAPER St. Vincent arrowroot 200 grains Boiling water 10 ounces Crush the arrowroot to fine powder, then rub it to a paste with a little water, and let an assistant pour a few drams of boiling water while you ... Houdoy's Process 1858
The paper is floated upon a lukewarm solution of gelatine at 5:100, and when dry, on a bath of uranium at 10 or 15 per 100 of water. After exposure to the sun the image is developed with a solution of silver nitrate acidified with acetic acid. T... How To Make A Negative Drawing
The drawing paper for designs to be reproduced by the cyantotype and the other processes described in this book should be of a fine texture, free from opacities and very white; and, as the design must serve as a cliche it is a sine qua non that it... L Liesegang's Process 1865
Pour ammonia into a nitrate of uranium solution, wash the precipitate of uranate of ammonia in distilled water, then dissolve in citric acid. Mix this solution of citrate of uranium and a little of a solution of chloride of gold with a paste pre... Niepce De St Victor's Process 1859
Red Prints. Float the paper for fifteen or twenty seconds on a 20 per cent. solution of nitrate of uranium and dry before the fire in the dark room. This paper can be prepared many days before use. Expose in sunshine from eight to ten minut... Preparation Of Red Yellow Or Blue Tissues
Red Tissue.--Dissolve 10 grams of carmine in 1 liter of aqueous ammonia and evaporate. When the smell of the alkali has almost disappeared, add 1 liter of rain water. Of this take 65 cubic centimeters, add 35 c.c.m. of rain water, and in the sol... Printing On Wood Canvas Opal And Transparencies
Printing on Wood.--To print on a wood block a design to be engraved on the same presents certain difficulties. In the first place, the sensitizing solution must not be absorbed by the wood, but remain wholly on its surface; then the photo film, a... The Aniline Process
The aniline process was published in 1865, by Mr. Willis, the inventor of the platinotype.(11) It is based on the oxidation of aniline by chromic acid, thus: A sheet of paper brushed with a solution of potassium bichromate and sulphuric acid, drie... The Black Or Ink Process Ferro-tannate Process
This process gives black positive impressions on white ground from positive cliches, and negative impressions from negative cliches. It has been attributed to Mr. Colas, but in reality it was invented by Mr. Poitevin, who describes it as follows ... The Carbon Process
The carbon tissue is seldom prepared by photographers. However, for the sake of completeness, we shall give the formula of the mixtures most generally employed, and describe the manner of coating the paper on a small scale. Preparation of the T... The Cuprotype Burnett's Process
This process gives positive impressions from negative cliches. Uranic nitrate 10 parts Cupric nitrate 2 parts Water 100 parts Float for a minute strong, well-sized paper on this solution and let it dry spontaneously in the dar... The Cyanofer Pellet's Process
This process gives blue impressions on a white ground from positive cliches, and white impressions on a blue ground from negative cliches. It is termed "positive ferrotype process." The cyanofer is an application of one of the numerous and usefu... The Cyanotype Or Blue Process
This process gives white impressions on a blue ground with diapositives or drawings on transparent or semi-transparent materials, and blue impressions on a white ground from negatives. It is commonly known under the names of "blue print process,"... The Platinotype
This process, discovered by William Willis,(16) yields very fine impressions which wholly consists of platinum and are, therefore, chemically permanent. It has been described theoretically and practically by Pizzighelli and Kuebl in a paper f... The Primuline Or Diazotype Process
Primuline, discovered in 1887 by Mr. A. G. Green, an English chemist, is a dye of a primrose color, possessing a great affinity for cotton fibers, to which it is readily fixed by simply immersing the material for a few moments in a hot solution of... The Uranotype
This process, devised by J. Wothly, in 1864, did not receive from the photographers the attention it merits, as it is always the case when a process is patented, and can be replaced by another equally practical which is not. It gives pictures of ... Tracing Process On Metal
We call the attention of metal engravers to this process. It is well known that wood engravers have their original designs photographed on the block in order to save considerable time by not making the drawing themselves; moreover the cost is nom... X's Process 1865 Secrets Of The Uranotype
Preparation of the Uranium Compound.--Precipitate the nitrate of uranium from its solution by concentrated liquid ammonia. Let settle the precipitate, decant, and wash in several changes of water. Dissolve it by heat in pure nitric acid, taking ...