US1436125A

US1436125A - Max ulljcann

Info

Publication number: US1436125A
Authority: US
Publication date: 1922-11-21
Anticipated expiration: 1939-11-21

Description

Patented Nov. 21, 1922.

UNITED STATES PATENT OFFICE.

MAX ULLMANN, OF ZWICKAU, GERMANY, ASSIGNOR TO KARL WERTH, OF THE HAGUE,

HOLLAND. y

PRODUCTION OF NEGATIVES.

Application filed January 2, 1914. Serial No. 810,092.

(GRANTED UNDER THE PROVISIONS 0F THE ACT 0F MARGH 3, 1921, 4]. STAT. L., 1313.)

To all whom, it fm r/,g/ concern Y Be 1t known that I, MAX ULLMANN, a citizen of Germany, and a resident ot Zwickau, Saxony, Germany, have invented certain new and use'ul Improvements in the Production ol? Negatives, or" `which the 'lollowing is a specitication` The invention relates to a process :tor the production of negatives from originals which are adapted to relect light from at least a portion of their surfaces and the object is to provide quickly and cheaply a welldeiined, direct copy of the original, more particularly with a view for further use in the production of plates :tor printing.

My invention will best be understood by reference to the following description of an illustrative embodiment thereof taken in connection with the accompanying diagrammatic drawings. wherein Fig. 1 is a plan view with parts successively broken away illustrating the process of copying,

Fig. 2 is a section on the line 2 2 ot Fig. 1,

Fig. 8 is a plan ot the negative, and

Fig. l is a section on the line l1-4; et Fig. 3.

It will be understood that in the drawin the thickness of the various layers is enormously exaggerated.

In practicing my invention, l may providey a translucent carrier 10, such as a glass plate, which carries a translucent iilin l1 ot chromated colloid, such as bi-chromated gelatine. This is laid on the original 12 which is to be copied with the iilm 1l in face to tace contact therewith, as illust-rated in Fig. 2, and light rays 13 from a suitable source are passed through the layers l0 and ll and are reflected at i4 'from the white portions of the original but are absorbed by the black portions Such as ordinary print. The portions of the sensitive film ll opposite the white portions oiz the original. are thus renderedy insoluble by the reflected light. The negative is then washed in water or dilute acid to remove the portions which have not been so rendered insoluble. There is thus produced on the plate 10 a negative defined by the insoluble portions of the chromate colloid layer and exhibiting the design corresponding to the black or colored design of the original in intaglio where the soluble colloid has been washed away. After the washing. the plate is dipped in one or more suitable coloring or dyeing baths, ior example, a bath ot' soluble aniline dye such as methyl violet, and the parts of the colloid layer remaining on the plate arc thus colored and made relatively opaque, the plate 10 being resistant to the dye. The resulting negative may be further used in the production of printing plates and forms, 'for example, it may be copied upon a sensitized printing plate and printing carried on by the offset process in the usual way.

In Fig. 1 portions of the capital R representing the original on the image are section lined for black merely to indicate that they are beneath the plate 10 and film 11. As the latter are transparent obviously the image would show with practically complete intensity. In Fig. 3 representing the negative the dyed colloid iilm is lined to represent purple, this being merely for purposes of illustration and not by way of limitation to a particular color.

The film ll or bi-chromated colloid is au example of a translucentmaterial adapted without substantial change in its light trans mitting properties to be rendered differentially soluble by the action o1 light so that a portion thereof may thereafter be selectively dissolved by a suitable reagent and washed away. Because it does not print out it may be subjected to the actinic action ot light for an adequate time. This is of a particular advantage when the original to be copied is printed on both sides, as, Jfor example, in reproducing a book. It has been found that no difficulty is encountered with shadows from the printed matter on the reverse side of the original not in contact with the colloid film and I believe this to be the case because the passage oi. the light is .not immediately obstructed as soon as the material is exposed to light, but a continued action of the reflected light is permitted which, metaphorically speaking, burns out any shadows which might be due to a slight absorption of the light by printed Ymattei' on the reverse side of the original.

The materials utilized in the process are very cheap and may be handled without the aid of a camera and with ordinary care may be manipulated in daylight.

Having thus described one embodiment of my invention, and Without limiting myself thereto, what I claim as new and desire to secure by Letters Patent, is as follows:

1. A process of producing negatives from originals 'adapted to reflect light from a portion of their surfaces which comprises placing over the original a film of translucent material which becomes differentially soluble under the action ot light Without substantial change in its light transmitting properties, transmitting light therethrough to be reflected in part from the original, washing out the soluble portions of the film and dyeing the remaining portions to produce an image.

2. A process for the production of negatives from originals adapted to reflect light from a portion of their surfaces which coinprises placing a bi-chromated colloid film mounted on a translucent carrier :face to face with the original, transmitting light therethrough to he reflected .in part from the original, Washing the carrier and film to remove unaffected portions of the film and dyeing the remaining portions to produce an image.

3. A process for the production of negatives from originals adapted to reflect light from a portion of their surfaces which comprises placing a bi-chromated colloid film mounted on a translucent carrier face to face with the original, transmitting' light therethrough to be reflected in part from the original, Washing the carrier and film to remove unaffected portions of the film and dyeing the remaining portions to produce an image7 said carrier being resistant to the dye.

4. A process of producing negatives from originals Which are `adapted to reflect light from a portion oit their surfaces which includes the step of placing over the original a translucent sheet comprising a film of bichromated colloid and transmitting light therethrough to be reflected in part from the original thereby to forni a negative image in the hi-chromated colloid.

In testimony whereof I afiix my signature in presence of two Witnesses.

MAX ULLMANN Witnesses lVALDnMAR HAUPT, HENRY HAsPER.