US 1386995 A
Description (OCR text may contain errors)
FELR DOREL, 0F
manurao'ruan or ennarrnous corarosons .ron usifm manrnonuc rron r LINE DGCUU. Ts
Dorel process, ferro-gelatinography, gela-- tin process, paste process, ozofer process,
'ordoverax process, etc., the working of which is as follows:
A gelatin composition previously melted in a water bath is spread on a sheet of zinc, copper or aluminium or on glass, marble, linoleum, etc. When the composition has set, a blue print (ferro-prussiate' paper) which has been previously 'ex posed behind the original or tracing to be reproduced so as to obtain a photographic. image of the latter, is applied to the surface. This blue print which is an exact image of the original, is applied to the composition dry, that is to say non-developed or fixed by water. As a result, a chemlcal reaction takes place 1nstantaneously between the gelatin composition and those parts of the sensitive paper which have not been exposed to light and correspond to the writing, lines, etc. on the tracing.
There" is produced in short on the gelatin composition a photographic transfer of the original to be reproduced, which transfer constitutes a block that can be inked with printers ink. The inking having been done, it is suflicient to apply to the block a sheet of paper and to exercise a slight pressure in order to obtain a copy of the original. Many copies can be so obtained.
In the said process the gelatin composition always comprises two undamental products: gelatin, and a metal salt such as ferrous sulfate. It is also possible to add glycerin, formol, quinone, quinone sulfonate of sodium, alums, etc.
The gelatin composition obtained in the above mentioned manner is a brown or reddish-brown or yellow-brown or yellow mass. After it has beenspread on the support, its color persists, but gradually be- Specifieation of Letters Patent.
Patented Aug. 9, 1921.
Application filed. December 2, 1918. Sierial No. 265,033.
comes less strong as the layers become thinner. Certain compositions become even practically transparent. This results in insufficient legibility of the inked block, more particularly in th case of inks having a color approaching that of the gelatin compos tion, or a bad inter retation of the colors deposited by the in ing roll. Moreover, certain accidents which happen fairly frequently in the course of working, such as partial doudingflnk lines deposited by the edges of the inking roll, various stains which do not form part of the drawing, and which are reproduced in the copy, are diflicult for the operator to notice when .he has not had a long experience with the process.
he present invention makes it possible to avoid these various drawbacks. The invention comprises a white gelatin composition which can be used for the reproduction of drawings, maps, plans, manuscripts, music, etc. If to the usual composition is added a white substance such as for instance white of baryta, kaolin, etc., or any other substance which does not exercise any action on the gelatin, or if, in the interior of the gelatin mass, there is produced by a double decomposition process, a white precipitate (barium sulfate, carbonate of lead etc), a white gelatin composition will be obtained which has all the properties of the usual composition, but offers advantages which do away with all the drawbacks above referred to.
The learning and the use of the process are then facilitated, since in working on a white background, the operator notices at once the least clouding, or the smallest stain.
A gelatin composition which gives good results, is obtained in the following man ner:
Melt in a water bath 100 gr. gelatin and 200 gr. water. The melting having been completed, add successively with .constant stirring the following hot solutions:
100 gr. water, 70 gr. sodium sulfate, gr. water, 40 gr. barium chlorid,
then- 20 gr. water, 1.5 gr. ferrous sulfate.
can'm'oreoverbe brought about by means of other substances, provided that it leaves as the result a white preci itate. Glycerin, formol, alums, etc, can e added to the composition without afi'ecting its color.
The composition prepared as stated above can be used in the usual manner.
What I claim is:
1. A gelatinous composition for use in the reproduction of line documents, formed of gelatin, ferrous sulfate, and substances adapted to produce in the interior of the composition a white precipitate by a double decomposition process, for the purpose described.
2. A gelatinous composition for use in the reproduction of line documents, said composition consisting of gelatin, ferrous sulfate and a white substance which exerts no chemical action on the gelatin for the purpose described.
3. A gelatinous composition for use in the reproduction of line documents, said composition consisting of gelatin, ferrous sulfate and substances adapted to produce in the interior of the composition a white precipitate by a double decomposition process, for the purpose described.
4. A white gelatinous composition consisting of gelatin, ferrous sulfate and a substance for whitening said composition by double decomposition thereof adapted, upon being formed intoa printing block and having received an imprint from a llned document, to retain printers ink for repeatedly reproducing said lined document.
5. A method of manufacturing a white gelatinous composition for use in the reproduction of line documents, consisting in first melting 100 grams gelatin in 200 grams water; second, adding hereto while stirring a hot solution of 70 grams sodium'sulfate in 100 grams water; third, adding in similar manner a hot solution. ofAO grams barium chlorid in 80 grams water; lastly adding in similar manner a hot solution of 1.5 grams ferrous sulfate in 20 grams Water.
6. A method of manufacturing a white gelatinous composition for use in the production of line documents, consisting in first melting gelatin in water; second adding hereto while stirring a hot solution of sodium sulfate in water; third, adding in a similar manner a hot solution of barium chlorid in water; lastly, adding in a similar manner a hot solution of ferrous sulfate in water. 1
In testimony whereof I aflix my signature in presence of two witnesses.