US2023858A - Copying process - Google Patents

Description

Dec. 10, 1935. E. SCHATZLER 2,023,853

COPYING PROCESS. I

Filed May 11; 1932 INVENTOR may Patented Dec. 10,1935

UNITED STATES PATENT, OFFICE COPYING PROCESS Ernst Schiitzler, Basel, Switzerland, assignor to Porros Patentverwaltung A.-G. Basel, Basel,

Switzerland Application May 11, 1932, Serial No. 610,713

In'Germany May 18, 1931 2 Claims. (01. 41-s1.5)-

, processes in that the copying sheets are not moistened but the original bearing reversed script capable of transfer is moistened on the side remote from the script or picture, and that dry.

copying sheets are successively pressed against the front side bearing the original reversed script in a separate operation.

Spirit, alcohol, water or any other solvent for the ink may be employed for moistening the rear side of the original, that is the side remote from that bearing the script or picture. Spirit and alcohol are to be used it upto sixty copies are to be made, but organic solvents for several hundreds of copies.

Any kind of writing paper may be employed for the original and any copying ink, such as crystal violet, may be used for producing the mirror reflected script.

The solvent is applied to the original by moistening the rear side thereof.

This may be efiected directly. However, suitable apparatuses can be advantageously employed for moistening the original and producing the duplicates. T

Such apparatus are illustrated by way 01' example in the accompanying drawing in which:-

Fig. 1 is a perspectiveview of a fiat duplicator. Fig. 2 shows arotary duplicator-in section.

The flat duplicator-according to Fig.1 consists.

of a plane plate 0 with an absorbent upper Sill-1 face b. The solvent is applied to this absorbent surface for example by means. of a'brush or the like, whereupon the sheet a,'.bearing' the original in mirror reflected script, is placed on the mois- -;tened surface with its side bearing the original script directed uppermost and pressed for ex-' ample by means oia roller. By the pressure the moisture of the surface 1) is transferred to the original and moistens it uniformly on its rear side. The dry copying sheets arethen placed successively on the dry upwardly directed side of the originalsheet and pressed for example The drum g of the rotary duplicator illustrated in Fig. 2 likewise has an absorbent surface d, for

. example a cotton covering, which can be moistened with a brush or the like. The sheet e bearing the original in mirror reflected script or 5 I picture is clamped on the moistened drum surface it in known manner, for example by means of a clamping device I with its front side-bearing the script directed outwards. Owing to the pressure between the drum 9 and the counter 0 pressure roller h the solvent is transferred from the absorbent drum surface at to the rear side of the original sheet e and moistens the same. The

' dry copying sheets i arethen passed between the drum g and counter pressure roller h and 15 pressed against the dry front side of the original as is customary in other processes, the ink being gradually dissolved by the moisturepercolating through the sheet and transferred to the copying sheets. y 20 The original is only slightly moistened. As the copy sheets are pressed on to the original by solvents are to be used. 30

, The "new copying process results in a saving in time and material and in other advantages. It

is only necessary to moisten the original once for all copies. According to the known process each individual copying sheet had to be moistened 35 which required much more time. The working,

with the new process is much quicker because the ink 01 the original continually dissolves and is ready for transierring after a single moistening. Hitherto the working speed was limited in 40 that the moisture of the copying sheet had to first dissolve the ink or the original. Moreover, according to-the new process the drying of the copying sheets after the pressing is saved. The saving in material is considerable, as the 4 single moistening or the original; requires muchless solvent than themoiste'ning of all the copying sheets. In duplicating apparatuses operating according to the known process with a bar for moistening the copying sheets, that portion of the copying sheets-which is enclosed between the moistening bar and the drum is lost. Moreover, it was impossible to print copies of very small size. As in apparatus according to the new, process the 56 moistening of the copying sheets is done away with, the head bar is utilized to full advantage and the printing of papers of very small size is possible.

Hitherto the strength of the copying sheet was detrimentaliy affected by the moistening. As according to the new process the copying paper remains dry, it is capable of resisting mechanical stresses to a greater extent. thinner and also perforated paper can be employed for the copies. Moreover, moist paper has a tendency to roll and crease. These objections are also overcome according to the invention in that the copying sheets remain dry.

I claim:-

1. A duplicating process, consisting in produc- Consequently,

ing an original in mirror reflected script or picture in copying ink on a sheet of paper, moistening this paper on the rear side, and in successively pressing the dry copying sheets on to the front side of the original bearing the mirror refiected script or picture.

2. A duplicatingprocess consisting in producing an original in mirror reflected picture or script in copying ink on a sheet of paper, moistening this paper on the rear side with a solvent 10 for the copying ink, thereby making the original ready for copying, and in successively pressing dry copying sheets on to the front side of the original bearing the mirror reflected picture or script. 15

, ERNST SCHATZLER.

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