US1059917A - Process of photography in colors. - Google Patents

Description

No Drawing.

AUGUSTE JEAN BAPTISTE TAULEIGNE, 01E PONTIG-NY, AND ELIE MAZO, OH PARKE,

FRANCE.

racemes or rnoroannrnr m coLons.

ma enta.

To all whom it may concern:

Be it known that we, AUcUs'rn JEAN BAP TISTE TAULEIQNE, of Pontigny Yonne, Re

public of France, riest, and ..JLIE. MAZO, of

8 Boulevard de a cute, in the cityof Paris, Republic of France, manufacturer of photographic apparatus, have invented an Improved Process of Photography in Colors of which the following is a full, clear, an exact description. p

The object of the present invention is to enable photographic positives to be obtained in all shades, by the transformation of anordinary silver positive into an amlin monochrome.

The present improved process can be employed for; 1st, obtaining simple positives 2 various reagents, which result in have the propertyof"precipitating several anilin colors. Such'salts include many of i the chlorids, bromids, ferricyanids and h others. .Amongthese, the most intere'sting for-"the purpose now. in hand, arethe chlo-' rid, iodid, ferricyanid and chromate of silver because it is easy to transform the reduced silver of photographs into anyone of: these compounds. 'Thesalt that hasgiven t-hebest results andwhich forms the object of the present patent is; iodid ofsilver objv tained. by double transformation: 1st. of

reduced silver into chlorid, bromid or ferro- 'cyanid of silver; 2nd. by transformation of positive after being well freed from hyppsuli these compounds into iodid of silver by the action of iodidof potassium.

The detail of the operations ,which this process comprises "is. the following: The

te is plunged in a solution of bic ferrocyanid,

be used,

of copper. Soon after the image w'hitens by being transformed into chlorid of silver or more robably into double chlorid of silv eran of copper. If this first trans formation was to be made into bromid of silver, thaprint would be immersed in a bromid at the maxium concentration, such as, ferric bromid and if it was to be made into ferricyanid of potassium would agents is of small importance. Whenthe The concentration of these 're-' specification or team Patent. 7 I Patented Apr. 2%, W13 Application filed march 23, 1910. Serial No. MHJSE. I i i v transformation is complete, the print is washed in order-to free it from thereagent' then it ,is plunged in a very weak solutionfof 1odid of potassium: 1% or 2%, at the maxi- J mum. In this bath the color of theimage which was a brownish white is changed to agreenish white and the print is transfomned into iodid of silverormore probably into double iodid of silver and of copper, or- -of silver and of-iron, or ofsilver and of pfotassium accordin to thereagent used in the first transformation This; double transfor- J mation is extremely important since bgd reet.

-teed transformation the monochromesm are not sufficiently ntense, Afterthis'tra'nsbath follows. A suflicientthough small numberof anilin colors re-act well in the presence of-iodid'of silver. Those which-operate formation of the image, immersioninadye-v "the best are: the red of rosanilin or fuehsin,

the blue of methylene, or the blue commonly known-as blue 149, and ordinary auromin,

- for trichromes. For by-color prints intended 'for stereoscopic projection, a mixture of fuchsin and auromm in predetermined. .pro-

portions, and the sen known to commercebythe name ofbr' liant green or ethyl reen,

iis'preferred. The aqueoussolutions 0 these, several coloring matters should be relatively weak and contain a small roportion, of

acetic acid, which favorsim ibitio'n while preventing the filling up of the whites.

However the degree of'concentration need notbe rigorously insisted upon and a weak bath, in courseiof time,'. produces monochromes as intense as thoseproduced by a concentrated bath.

The image of iodid of Sinai a tum;

after being washed for some minutes in border to eliminate iodid of .potassium, is plunged into the selected coloring solution.

The time of imbibition is about 12 .hours. The termination of this operation can be noted by observing when the coloration is as intense on the back as on the face of the plate or film-carrier. If the whites are tinted, the print is cleared or washed out either in plain water, or in water containing a small quantity of acetic acid. After this the most important operation takes place. In this last mentioned operation the silver salt of the sensitive film 1S caused to vanish Without removing the color and even without permitting it to diffuse through the gelatin. Two methods are available.

According to one method the 'rint is fixed in a bath of iodid of potassium of 20% strength. The iodid of silver is rendered completely transparent without however disappearing. The monochrome therefore a has all thepurity of color which character- I 'fectmg the iodid of silver, the fixing of the print can therefore be thereafter accompllshed without fear of--in]'ury.-

Two methods of-fixing are available after the treatment with tannin, the hyposulfite of soda method, and the cyanid of potassium method. For fixing by means of hyposulfite of soda, after having removed the greater part of the tannin contained in the senslt ve film by a' thorough washing, the prlnt 1s plunged into a concentrated or saturated bath of hyposulfite. The period for fixing 1s about ten minutes. In a less con.-

centrated bath the fixing will be difiicult and often 1ncomplete. It is now only necessary to eliminate the hyposulfite by a thorough washmg. The employment of tannin, besides being indispensable for fixing the colors, leaves them in the gelatinin a precipitated form which gives them an extraordinary solidity. i

In order to fix by meansof cyanid of potassium, the print, after the. treatment with tannln, 1s plunged mto a solution of cyanid ef potassiunrof about 10% strength. The IOdld of s1lver disappears very rapidly,

contrarily to what happens with the-fixing by iodid o f-potassium which only renders the silver salt transparent without removing it, the fixing by hyposulfite and by cyanld fdeterlnme \a real dissolution and the 1od1d .of silver. is completely eliminated.

- a bath of tannin;

sists in the treatmentof the positive sists in the treatment of the for the The monochrome is then washed first in plain water in order to eliminate the excess of cyanid then in water slightly acidulated with acetic acid and finally washed with a large quantity of water.

Only prints with free tones formed solely I by anilin colors have hereinabove been men: tioned, but positives in less intense colors can be obtained. In this case, in place of fixing the positive after imbibition and washing out, the positive is passed through then washed, and the iodid of silver re-developed in any suitable developing bath. The print is, in this case, formed by'reduced silver the tone or shade of which is modified by the anilin color.

In conclusion, the present improved process for transforming a silver print into an anilin print, is quite a general process in which the order of the operations is as fol-.' lows :1. Transformation of reduced silver into chlorid of silver by bi-chlorid of copper. 2. Transformation of chlorid of silver into iodid of silver by a weak bath of iodid of potassium. 3. Imbiiition in a weak'bath of a selected anilin co or, 4. Washing the print in plain water or in acidulated water. 5. Fixing thecolor in a 9% to 10%solution of tannin. 6. Elimination of the excess tanninb means of plain water. 7. Elimination 0 the silver salt by means of concentrated hyposulfite of soda or by cyanid o 'f potassiumof about 10% strength. 8. -El1m1- ,nation of thefixing reagent by a final washing.

' Claims-'-- 1. The herein described steps in -a process for the production of colored photographs from ordinary silver positives, which conwith bichlorid of copper, subsequently treating it-with iodid of'potassium, immersing it in an anilin dye-bath, washing with water, fix ing the color by immersion in a solution of tannin, washing to eliminate excess of tan-.

nin, fixing the print, and finally washing to eliminate the fixing reagent. I 2. The herein described steps ma process for the reduction of colored photographs from or inary silver posltives, which conositive with bichlorid of copper, subsequent y treating 1t with iodid of otassium, immersing it in an anilin dye-bat washing with water, fixing the color by immersion 1n a 3% to 10% so; lution of tannin, washing to elimmate ex cess of tannin, fixing the print by means of hyposulfite of soda, and finally washlngthe .print to eliminate the fixing reagent.

3. The herein described steps in a pro ess production of colored photo raphs from or inary silver positives, whic consists in the treatment of the positive with bichlorid of copper, subsequently treating twith 'odid ofpotassium, unmersing it. in

an anilin dye-bath, washing with. water, The foregoingspecification' of-our im- .fixingthe color by immersion in a 3% t0 proved. process of photograph in colors 10 10% solution of tannin, washing to elimisigned by us this ninth day of arch 1910.

nateexcess oftannin, fixing the print by AUGUSTE JEAN BAPTISTE TAULEIGNE. 5 means of a concentrated solution of hy- ELIE MAZO.

' posulfite of soda; and finally washing the Witnesses:

print in order to eliminate the fixing re- H. 0; Com,

agent R. Tnmror. v