US2158194A

US2158194A - Photographic material

Info

Publication number: US2158194A
Application number: US53381A
Authority: US
Inventors: Murray Alexander
Original assignee: Eastman Kodak Co
Current assignee: Eastman Kodak Co
Priority date: 1934-05-24
Filing date: 1935-12-07
Publication date: 1939-05-16
Anticipated expiration: 1956-05-16
Also published as: DE675799C; US2204147A

Description

May 16, 1939. A. MURRAY PHOTOGRAPHIC MATERIAL Original Filed May 24, 1934 LIGHT SENSITIVE RES/S T METAL FOIL RUBBER \ZSUPPORT ATTORNEYS.

Patented May 16, 1939 UNITED STATES PATENT OFFICE PHOTOGRAPHIC MATERIAL Jersey Original application May 24, 1934, Serial No.

Divided and this application Decemher 7, 1935, Serial No. 53,381

3 Claims.

This invention relates to a photographic element which may be used for making etched designs on glass and metal objects, such as bowls, tumblers, vases, cylinders, stem-ware, and the like.

This case is a division of application Serial No. 727,304, filed May 24, 1934, now Patent N0. 2,073,313, issued March 9, 1937. i

It has been difficult to make deeply etched or cut designs of uniformly high quality upon the surface of solid objects such as stem-ware, except by processes requiring a large amount of time consuming and highly skilled hand work. I have invented a method of etching such glassware ina simple and comparatively inexpensive manner. This comprises the formation on a freely extensible sheet, such as rubber, of an image that is extensible with the rubber and applying this image bearing stencil or negative, preferably in the form of a closed or tubular band, to the surface of the object to be etched, which also carries a sensitive coating. This is then exposed to uniform illumination from all sides, the negative removed, and the glass or metal etched by a photoengraving process.

My invention resides in the various methods herein described of makingthe elastic stencil, in

the sensitized elastic element, and in the completed elastic stencil band.

Reference will be made to the accompanying drawing, in the several figures of which like numerals represent like parts and in which:

Fig. 1 is a section on an exaggerated scale of a. sensitized element made according to my invention.

Fig. 2 is a similar section of the element after exposure and removal of the resist at the exposed portions.

Fig. 3 is a section of the element after etching.

Fig. 4 is a section of the element after appli cation of a dye thereto.

Fig. 5 is a section of the elastic sheet bearing the dye design, after removal from the support.

Fig. 6 is a perspective view of a frame carrying an endless rubber stencil strip.

Fig. '7 is a similar view showing the band expanded to permit insertion of a goblet to be ornamented.

Fig. 8 is a similar view showing the goblet and band in position for printing.

It is obvious that a prime desideratum in a photographic negative or stencil having a highly flexible or elastic base is that the image shall be fully as extensible and flexible as the support. This is not the case with ordinary photographic emulsions of gelatine, collodion or the like, and the image, if formed originally in such a layer. must be printed or stenciled upon the support itself and the original layer removed.

I will first describe my preferred method of forming such a stencil or negative, reference being made to Fig. 1.

Upon a suitable support I which may be a glass plate, a sheet of a cellulosic derivative composition, waxed or otherwise waterproofed, cardboard or any other reasonably rigid sheet, a thin, elastic, soft, translucent, vulcanized rubber sheet 2 is temporarily attached by means of a suitable stripping adhesive, such as wax or a rubber cement. The rubber sheet would be held smoothly but ordinarily not under tension. A suitable cement is a .5% solution of rubber in benzene.

Commercial rubber sheeting having a thickness of .003-.004 inch is preferred but the thickness may vary within wide limits, as between .0005 and .01 inch.

A thin, preferably unelastic stencil material 3.

as for'instance, a sheet of brass, nickel or other metal foil .001 inch thick, is then attached to the rubber layer by means of a rubber cement. If the element is to be used immediately, brass is preferred, but since brass tends to affect rubber if kept in contact with it, nickel or some other inert material would be used if the plate is to be stored for some time.

To the sheet of foil 3 is then applied a coating 4 of a light sensitive resist, an example being the following:

- .Grams Dicinnamal acetone 32.5 Syrian asphaltum 97.5 Phenol 1.80 Solvent naphtha (coal tar) 500.0 Toluene 270.0

element after this treatment is illustrated in Fig. 2. the resist being indicated by 4.

The stencil sheet is then etched in the exposed parts of the design with aqueous ferric chloride solution of above 86 Baum until the brass is removed to the rubber which the etching solu tion does not affect. The element then appears .as shown in Fig. 3, the etched brass sheet being indicated at 3'. After rinsing with water and drying, the etched surface is treated with a stain, solution or dye which deposits upon the areas of rubber laid bare by etching, a coloring matter which becomes physically extensible with the rubber, as indicated at 5 in Fig. 4. This may be a rubber ink" or stain, sprayed or brushed upon the stencil and coating the rubber in the stencil openings. This solution may consist of:

Grams Nigrosine (Schulz No. 985)-; 5 2% crepe rubber in benzene 30 Ether 65 thereto by a stripping layer, separates from it.

There is now left a rubber sheet 2, as shown in Fig, 5, having the properties already enumerated and carrying susbtantially integral with it and extensible with it, a light absorbent or obstructive pattern 5'-formed as a result of a photographic process.

A second method of making'the negative is by applying to the rubber layer a bichromated fish glue solution of familiar type such as Photo-engraving glue (fish glue) grams 360 Ammonium bichromate do 55 Water liter 1 When dry, the plate is exposed to a suitable light design, the print developed by washing in water, and dried. It is now covered with a suitable stain such as the one already described, or

Grams Oil Red C dye (Schulz No. 532) 1 Nigrosinei 4 1.0% rubber solution in benzene 20 When dry, the rubber sheet is stripped from the temporary support and washed in warm water to remove the remaining glue. This is aided by stretching the rubber. There is left a rubber sheet carrying a stain, which ordinarily will be a line image.

A third method, which is non-photographic, of making the rubber negative or positive will now be given. The rubber sheet is placed over a design to be copied. The rubber sheet may be either mounted on a glass sheet as before or placed tightly on the design on a drawing board and both held in place by thumb tacks. The design or pattern is then drawn in water color on the rubber by hand using a suitable fine brush.

When dry it is stained with dye solutions of the type already described. The water color is then washed off leaving the stain image.

Still 'a fourth method is the following. A rubber sheet, mounted as before, is coated with a silver halide-gelatine emulsion, exposed to a light image of the design, and developed in a tanning developer of known type, such as pyro. The untanned gelatine is removed by washing in warm water. After drying the negative is stained as above described and the remaining tanned gelathan another.

tine stencil removed by any usual means that does not attack the rubber or the stain.

By whichever method isused, there is obtained an elastic negative,' the support of which is a thin, elastic, soft, translucent, vulcanized sheet of rubber carrying a perfectly extensible design in or on its surface, and which stretches and contracts with the rubber support without cracking or peeling. Numerous uses. of such a negative at once suggest themselves. It may be used for making distorted or cartoon pictures by extending the rubber sheet more in one direction The effects of motion, useful in making animated cartoons, may be made by constantly changing the extension of the rubber in one or more directions or unevenly. If extended uniformly in all directions, an enlarged print may be made by direct contact printing.

By stretching to a precisely determined degree, a negative having calibration marks on it may be used in the calibration of individual instrument scales where the same scale readings are shown but in somewhat different dimensions on the several instruments.

The principal use which I have in mind, however, is the printing of photographic designs upon the surface of an object having other than a plane surface.- Such objects may be glass-ware, such as bowls, tumblers, jars, stem-ware including goblets, wine glasses and vases, and other dishes; metal cylinders used in printing processes or for any other purpose; molded metal forms, such as picture frames, convex dials, watch cases and furniture parts and other objects too numerous to catalog. In general the print would be made by stretching the negative over or around the object to be ornamented or marked and which would carry upon its surface a light sensitive coating. The rubber sheet would by its own tension hug closely and contact the surface of the object except for concavities. The first photographic image could be the permanent one if the object were not to be subjected to rough usage but the coating usually would be of a type adapted to act as a resist, and after-exposure, would be developed by a wash-off or solvent process, leaving a resist design through which a suitable etching fluid could act on the metallic or glass object, after which the resist would be removed. The particular resist used would have to be one capable of withstanding the etching fluid used. Many such are known for use with metallic surfaces but few photographic resists are known prior to my invention capable of withstanding the action of hydrofluoric acid ordinarily used for glass etching.

Reference will nowbe made to Figs. 6, 7 and 8 which show a device for applying the negative to the surface of an object such as a goblet. A negative strip l0 bearing a repeat design II, has its ends secured by a suitable rubber cement in an air tight seam I2, thus forming an endless or cylindrical rubber negative, the size of which, when unextended, is less than the article to be etched or ornamented. The edges of this negative are secured between clamping blocks of a suitable frame. This frame consists of a glass cylinder I3 having tightly fitting metal or rubber annular rings 14 and IS in its opposite ends. These rings have cut out annular rabbetswithin which fit smaller rings IS on their outer surfaces. The ring I6 is removed from ring l4 and, while one edge of the negative band is held stretched, is replaced, clamping the edge between the rings l4 and Hi. The other edge of the band is then clamped to the ring l in a similar way. The normal position of the band is shown in Fig. 6. Through the ring l5 pass two tubes I1 and I8, with stop cocks I9 and 29, the first tube being connected to a source (not shown) of compressed air or, preferably, of a compressed inert gas and the other to a suction device (not shown), or both may be connected to a circulating supply of an inert cooling fluid. When the stop cook 20 is opened and the cock l9 closed, air will be with drawn from the annular space between the glass cylinder I3 and the rubber negative l0 and the latter will be drawn outwardly as shown in Fig. 7. The goblet 2| or other article carrying a sensitive coating on that portion of its surface to be ornamented is then placed within the casing as shown in the same figure and stop cock l9 opened while 20 is closed.

Even if the tube I! were open to the air, the

contraction of the rubber negative band I I would I tinuously exposed, tends to deteriorate rapidly For this reason I prefer to use an inert fluid rather than air and to circulate this through the space between the rubber negative and the glass cylinder. This fluid may be an inert gas or a liquid such as water.

The whole device containing the article 2| is then rotated at a uniform rate before a light source for as long a time as maybe required for the exposure, depending on the intensity of the light and sensitivity of the particular coating on the article 2h The light passes through the glass which is unobstructed and through the negative producing a print on the sensitized surface.

It is to be understood that the description and formulae herein given are by way of example and that I consider as included within my invention not only all of the subject matter herein disclosed but also all modifications and equivalents thereof that fall within the reasonable scope of the appended claims.

, Having thus described myinvention, what I claim as new and desire to secure by Letters Patent is:

l. A sensitized element comprising a thin, translucent, elastic sheet of vulcanized rubber, a thin layer of metal foil removably secured to one surface of the rubber sheet and a photographically sensitive layer over said metal foil.

2. A sensitized stripping element comprising a rigid support, a thin, translucent, soft, elastic, vulcanized rubber sheet secured thereto by a stripping layer, a resist layer applied to the rubber sheet and a photographically sensitive layer applied to the resist layer.

3. A sensitized stripping element comprising a rigid support, a thin, translucent, soft, elastic, vulcanized rubber sheet secured thereto by a stripping layer, a thin layer of metal foil removably secured to the rubber sheet and a photographically sensitive layer applied to the metal foil.

ALEXANDER. MURRAY.