US2073313A - Method and apparatus for ornamenting curved surfaces - Google Patents

Description

A. MURRAY March 9, 1937.

METHOD AND APPARATUS FO R ORNAMENTING CURVED- SURFACES Filed May 24, 1954 4-Ligib duo Inu Patented Mar. 9, 1937 UNITED STATES METHOD AND APPARATUS FOR ORNA- MENTING CURVED SURFACES Alexander Murray, Rochester, N. Y., assignor, by

mesne assignments, to Eastman Kodak Com- 1 m], Jersey City, N. 5., a corporation of New Jersey Application May 24, 1934, Serial'No. 727,304

6 Claims.

' This invention relates to a photographic element and to methods of utilizing the same particularly for the purpose of making etched designs on glass and metal objects, such as bowls,

tumblera vases, cylinders, stem-ware and the like.

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 suchglass-ware in a 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 photo-engraving process.

My invention resides in the various methods herein described of making the elastic stencil, in the sensitized elastic element, the completed elastic stencil band, and the various processes and the steps and details thereof for utilizing the band for various purposes as hereinafter more fully described and claimed.

Reference will be made to the accompanying drawing, in the several figures of which the same characters designate the same elements and in which: i

Fig. 1 is a section on an exaggerated scale of a sensitized element embodying certain elements of my invention.

Fig. 2 is a similar section of a rubber stencil made from the element of Fig. 1.

Fig. 3 is a perspective view of a frame carrying an endless rubber stencil strip.

Fig. 4 is a similar view showing the band expanded to permit insertion of a goblet to be ornamented.

Fig. 5 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, highlyflexible 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 5 forming such a stencilor 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 orany 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 aiiect 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 -1 32.5 Syrian asphaltum 97.5

Phenol 1.89 Solvent naphtha (coal tar) 500.0 Toluene 270.0

The resist mentioned is of the type covered in my prior Patent No. 1,956,710, granted July 10, 1934, and forms a hard coherent coating.

Aline negative or positive is placed in contact with the sensitive coating and exposed to the light of a 30 ampere arc lamp at a distance of 24 inches for 5 minutes. The unexposed parts of the resist are removed by treatment with kerosene. The solvent action iscontrolled by observation and is stopped by removal of the kerosene by washing with soap and' water.

The stencil layer is then etched in the exposed parts of the design with aqueous ferric chloride solution of above 36 Baum until the brass is removed to the rubber which the etching solution does not affect. 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 material which becomes physically extensible with the rubber. 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 An enlarged section of the negative at this stage is shown in Fig. 2, where the supportis indicated at I, and. rubber sheet at 2, parts of the metal foil layer constituting stencil areas are shown at 3' and of the resist at 4'. Between these stencil areas are areas 5 of stain or dye directly upon the rubber. The resist areas would also be more or less colored but no use is made.

of that fact which is merely incidental.

The stencil foil sheet carrying the resist is readily stripped from the rubber by stripping the rubber sheet from the support and then stretching it, whereupon the inextensible foil, not stretchingwith the rubber and being attached thereto by a stripping layer, separates from it. There is now left a rubber sheet having the properties already enumerated and carrying substantially integral with it and extensible with it, a light absorbent or obstructive pattern 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 Water ;-liteli When dry, the plate islexposed to a suitable light design, the print developed by washingin 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 Nigrosine 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 40 sheet carrying a stain, which ordinarily will be a line image. a j

A third method, which is non photographic, of making the rubber negativeor 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 designer 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 ofi 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, anddevelopedin a tanning developer of known type, such as pyro. The untanned gelatine is removed by washing in 0 warm water. After drying the negative is stained as above described and the remaining tanned gelatine stencil removed by any usual means that does not attack the rubber or the stain.

By whichever method is used, there is obtainedan elastic negative, the support of which is a thin, elastic, soft, translucent, vulcanized sheet-- cf rubber carrying a perfectly extensible design in or on its surface, and which stretches and contracts with the rubber support without crack- 7 ing or peeling. Numerous uses of such a-negative at once suggest themselves. It may be used I for making distorted or cartoon pictures by extending the rubber sheet more in one direction than another. 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 glassware, 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. graphic 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 The first photoadapted 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.

In the making of a photographic design around the entire periphery of an object such as a goblet, vase or cylinder, I have invented a novel technique which comprises the making of a tubular or endless rubber negative band carrying the desired image, holding this in an extended position, larger than the object to be ornamented or marked, placing the object within the negative and then releasing the tension on the band, permitting the band to contract and embrace the object closely.

Reference will now be made'to Figs. 3, 4, and

5 which show a device for applying the negative an air tight seam I 2, 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 nega- 'tive are secured between clamping blocks of 'a suitable frame; This frame consists of a glass cylinder l3 having tightly fitting metal or rubber annular-rings I4 and I5 in its opposite ends.

which fit smaller rings l 6 on their outer surfaces. The ring I6 is removed from ring I! and, while one edge of the negative band is held stretched, is replaced, clamping the edge between the rings These rings have cut out annular rabbets within I 4 and IS. The other edge of the band is then clamped to the ring I5 in a similar way. The normal positionof the band is shown in Fig. 3. Through the ring 15 pass two tubes l1 and I8,

with stop cocks I9 and 20, 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 fiuid. When the stop cock 20 is opened and the cock l9 closed, airwill be withdrawn from the annular space between the glass cylinder I3 and the rubber negative l and the latter will be drawn outwardly as shown in Fig. 4. 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 is closed.

Even if the tube H were open to the air, the contraction of the rubber negative band I I would ordinarily cause it to contact closely with the surface of the goblet, but in order to insure uni- 29 form close contact throughout, the tube I1 is preferably connected to a source of compressed article has portions of somewhat smaller diameter than the normal diameter ot the band H.

Since the exposures :are made'under rather high light and heat conditions, the rubber, if continuously exposed, tends to deteriorate rapidly. For this reason I prefer to use an inert fiuid rather than air and to circulate this through the space between the rubber negative and the glass cylinder. This fiuidfmay 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 may be required-for the exposure, depending on the intensity of the light" and sensitivity of the particular coating on the article 2 I. The light passes through the glass 40 producing a print on the sensitized surface.

With the sensitive resist given below, a continuous exposure of five minutes to a 35 ampere are light at a distance of 18 inches is neces- J sary. The article should, however, be rotated for 20 minutes to give each point the, equivalent of 5' Ordinarily, the tubes. l7 and I8 will be long and flexible and permitthe turning of the article through a single complete revolution. It may either make one very.

minutes direct exposure.

slow revolution or a series of slow oscillations, each a complete revolution. As a means for effecting this turning, the frame is mounted on a rotatable table 22 which may be rotated or oscillated from any suitable power source by means of the belt 23, this being shown merely by way of example.

A sensitive; resist suitable for use on glass is the following:

60 Grams Dicinnamal acetone 4.5 Syrian asphaltum 9.0 Phenol 2.0

Chlornaphthalene wax 1.5

60 Solvent naphtha 50.0

Toluene 33.0

which is unobstructed and through the negative nantly trichlornaphthalene, having certain physical properties of natural waxes. Various materials of this type are on the market and the particular chemical structure of the wax is not of primary importance. Such materials are sold under the trade-mark Halowax. In the formula just given, the chlornaphthalene wax, as sold commercially, or other hydrogenated wax or other natural or artificial wax or wax-like body, such as Montan wax, beeswax, or carnauba' wax are important in giving much better adherence of the resist to glass. I have also found that adherence may be increased if a certain type of sub-layer is first applied to the glass before the resist layer, which in this case need not contain a wax. This sub-layer comprises as an essential ingredient a triphenylmethane dye such as fuchsine, malachite green, methyl violet and-ethyl violet, the Schulz numbers of which are respectively 780, 754, 783, 787.

More or less resin may be added to the dye solution to decrease its solubility in water and improve the flowing properties. A preferred formula for the sub-layer as applied is as followsz.

. Grams Malachite green 1.00 Gum' mastic .04 Toluene .50 Denatured alcohol 90.46 Iso-propyl alcohol 8.00

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 therei of that fall within the reasonable scope of the appended claims.

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

1. The method of light printing a photographic image uniformly uponi the sensitized peripheral surface of an object that comprises holding in an extended stretched position a tubular, elastic, image bearing band, positioning the object within said extended band, permitting the band to contract into contact with the peripheral surface of the object and exposing the object to I light through the applied band.

2. The method of ornamenting the peripheral surface of an object that comprises sensitizing the surface of the object, holding in an extended stretched position a tubular, elastic, rubber image-bearing band, positioning the object within said band, causing the band to contract into upon the sensitized surface of an object and comprising a transparent rigid cylinder, heads having an air tight connection with the ends of the said cylinder, each head having means for clamping tightly the edge of an endless tubular elastic band, whereby such a. band may be supported by and between such heads, at least one oi the heads'having an axial opening through which an object with a sensitized surface may be inserted within such a tubular band, and means for removing air from and admitting air into the space between the cylinder and a band clamped upon the sensitized surface of an object and comprising a transparent rigidcylinder, heads havbetween the heads whereby the band may be distended leaving a large central openingor may be contracted around an object placed within the tubular band.

4. Apparatus for photographically printing upon the sensitized 'surfaceof an object and comprising a transparent rigid cylinder, annular heads having an air-tight connection with the ends of said cylinder, each head having means for clamping tightly the edge of an endless elastic bandfwhereby such a band may be supported by and between such annular heads leaving a central open space through the apparatus, and means for removing air from and admitting air into the'space between the cylinder and a band clamped between the heads.

5. Apparatus for photographically printing ing an air-tight connection with the ends of said cylinder, each head having means for clamping tightly the edge of an endless tubular elastic band, whereby such a band may be supported by and between such heads, at least one of the heads having an axial opening through which an object with a sensitized surface'may be inserted within such a tubular band, means for removing air from the space between the cylinder and a band clamped between the heads whereby such a band may be expanded and an object placed within it and means for forcing air into the same space whereby the band may be contracted against and forced into close contact with an object placed within it.

6. Apparatus for photographically printing upon the sensitized surface of an object and comprising a transparent rigid cylinder, heads having an air-tight connection with the ends of said cylinder, each head having means for clamping tightly the edge of an endless tubular elastic band, whereby such a band may be supported by and between such heads, at least one of the heads having an axial opening through which an object with a sensitized surface. may be inserted within such a, tubular band, means for removingfiuidfrom the space between the cylinder and a band clamped between the heads whereby such a band may be expanded and an object placed within it and means for forcing a cooling fluid into the same space and circulating it therein whereby the band may be contracted against and forced into close contact with an object placed within it and willbe maintained cool durin'g prolonged exposure to heat.

I ALEXANDER MURRAY.

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