US1578203A - Transfer film - Google Patents

Description

Patented Mar. 23, 1926.

UNITED STATES PATENT OFFICE.

CARL P. OLSON, OF IRVINGTON, NEW JERSEY, ASSIGNOR TO KARL E. OLSON & SON, INC., OF IRVINGTON, NEW JERSEY.

TRANSFER FILM.

No Drawing.

7 '0 all who-mat may concern.

Be it known that I, CARL P. OLsoN,- a citizen of the United States, residing in theto-wn of Irvington, county of Essex, and State of New Jersey, have invented certain new and useful Improvements in Transfer Films, of which the following is a description, as well as of the manner and process of making, constructing, and using the same, in such full, clear, concise, and exact terms as to enable any person skilled in the art or science to which it appertains or with which it is most nearly connected to make and use the same.

My invention relates generally to transfer films, and particularly to imitation metallic leaf, supported upon a flexible backing.

My invention has for its objects the production of a transfer film of metallic pigments adapted to be used in hot embossing. Dependent upon the class of transfer work for which the film is to be used, the character thereof may be varied as follows: if the stamping is upon a rough surfaced material, such as book cloth, the film is made in the form of an integral, continuous tissue, such as self-supporting imitation metallic goldleaf; if the stamping is upon smooth surfaced material, as box covers of calendered paper, the film may be made in the form of a discontinuous leaf, such as the non-selfsupporting coating obtained by dusting imitation metallic powders without a binder.

In both cases, the film is backed by a flexible support upon which it is formed; in the former case referred to, namely, that of an imitation metallic leaf, by spraying a solution of a tissue-forming material; and in the latter case, namely, of a discontinuous film, by dusting with the metallic pigment. In either case, an adhesive coating upon the flexible support is provided, which coatingseparably attaches thetransfcr film thereto, and an important object of my invention is to provide an adhesive coating of such composition that, when transferred, the metallic pigments in the film will be preserved from exposure to atmospheric agents or other gaseous agencies liable to cause its deterioration, as by corrosion or tarnishing, and which adhesive coating will itself be neutral to Application filed June 19, 1924. Serial No. 721,143.

the metallic particles of the powdered pigments, so that no deterioration will result from contact therewith prior to transference.

To the foregoing ends, my invention consists in thep-rovision of a neutral wax as the adhesive combined with a neutral resin as the protector of the stamped leaf,

Further objects are the provision as such an adhesive ingredient, of a wax of high melting point, since I find that, within certain limits, the less susceptible a wax is to the heat of the embossing die, which heat approximates 245 1 ahrenheit, the better the transfer obtainable. I believe this is due to the melting point of the wax, which, if high, limits the effect of the heat of the impression faces to the lines of contact, the sur-,

rounding wax tending to remain inert. This heat-insulating effect thus serves the useful result'of localizing the melting, leaving the contiguous film intact, whereby the efl'ec tive transfer is limited to the lines impressed, and a clean cut transfer is attained as the result of embossing. is of sohigh a melting point as to satisfy all requirements with regard to stamping, its solidifying point being between 80 and ST" centigrade; its acid value, however, is between l and 7, and for this reason-I prefer Chinese insect wax, a hard, translucent white crystalline body, whose melting point is between 82 and 86 Centigrade, and whose solidifying point is between 80.5 and 81 centigrade, and which is substantially neutral, analyses showing but traces of acid therein. \Vith the wax adhesive, I mix a neutral resin, forexample, cumar, which is a synthetic resin derived from, cmnarone. These, when melted together, form the adhesive coating composition applied to the backing strip. As this backlng, I prefer a thin, smooth, tough, transparent parchmentized paper, such, for example, as that known in the trade as glacine, or glassine. w

The preferred method of making my improved transfer films isas follows:

I take three parts carnauba wax and one part cumar. These are ground together and placed in the steam-jacketed con'ipartment of a coating machine such as the Knowlton I find carnauba wax is applied to one surface of the strip in the usual manner of coating by such a machine, the lower of the steel rolls dipping into the wax and depositing the wax taken up upon the upper, with which it contacts, the glacine contacting with the top of the upper roll and thence passing to a second set of guide rolls, as is so well understood by those skilled in the paper-coating art as to require no drawings by way of illustration. The metallic coatlng is next applied thereto, either by dusting bronze powder thereon, or, if a continuous tissue is desired, as for book cover,

embossing, then I proceed as follows: the glacine strip, wax-coated as described, is next passed beneath a suitable spraying nozzle, such as that shown in U. S. Patent No. 1,165,440, granted December 28, 1915, to Karl E. Olson. The air for' spraying is first warmed to a temperature of about 100 Fahrenheit. The mixture to be-sprayed is composed of a quick-drying lacquer vehicle containing bronze powder, such, for example, as the leaf-forming solution described in U. S. Patent No. 1,158,265, granted October 27, 1915, to Karl E. Olson, the proportions being 84 per cent of bronze or other powdered pigment to 16 per cent of a vehicle composed of soluble cotton dissolved in amylacetate.

The foil coated backing strip, prepared in either of the ways described, is then passed through a second coating machine such as that set forth, and the metallic surface is coated with a suitable size, applied cold. A shellac size, composed of shellac dissolved in alcohol, is preferred.

\Vhile I have specified particular ingredients, as preferred for particular objects,

I do not intend to be understood as confining my invention to the identical substances cited by way of example. Any high melting point natural wax is suitable; likewise, any high melting point gum or resin is suitable, and particularly the spar varnish known as outside spar varnish.

The proportions of wax and resin may be varied, but the ratio should be observed of substantially one pound of wax to four liquid ounces of a linseed oil varnish. Similarly, the method of coating exampled is not described as a limitation but is intended only as an advantageous one when the product is to be produced upon a commercial scale. The size coat may be omitted, but its addition obviates the necessity otherwise presented of sizing the book cover, box top or other article to be stamped, and it acts as a protector.

The especial advantages obtainable with a hacked or supported film are that the desired covering power is secured by a thin ner tissue than if the leaf is a self-supporting film, and that in stamping titles or fine lines of ornamentation, it is found that the thinner the film, the cleaner and clearer are the transfers produced. Not only is the result superior, but the labor-saving is very great, the cleaning out operation or scrubblng, as it is termed, being reduced to a.

minimum, the surplus film transferred being negligible.

The utility of a neutral composition as'the binder between the back and film, combined with the neutral character of the film itself, results in a stamping that has in its elements none of the chemical properties inducin deterioration of the metallic transfer; an since the" heat of the embossing head serves to melt the cumar as well as the wax, causing a deposit upon the subsequently exposed transferred surface of a thin coating of transparent varnish, the stamping is hermetically sealed and permanently protected against external elements liable to cause tarnishing or corrosion of the metal.

Having thus described my invention and the best method and means for embodying and practicing the same, I claim:

1. A film support consisting of a ribbonlike strip of flexible material, alayer thereon consisting of Chinese insect wax and varnish, and a coating of metallic powder upon said layer.

2. A film support consisting of a strip of surfaced paper, a layer on one face thereof consisting of a mixture of wax and cumar, and a coating of bronze powders upon said layer.

3. A film support consisting of a flexible backing, a layer thereon composed of a neutral -wax of high melting point and of a resin of high melting point, and a coating of metallic tissue upon said layer.

4. A film support consisting of paper of the character of glaeine, a coating thereon composed of a wax of high melting point and a synthetic resin, and a metallic tissue dissolvably held to said support by said coating.

5. A film support consisting of a ribbonlike strip of flexible material, a coating thereon composed of a wax of high melting point and cumar, and a metallic tissue at- 9. A film support consisting of paper 11. A film support consisting of a ribbon coated with a mixture of wax of high meltof glacine coated with wax mixed with resin, ing point and a neutral resin. :1 film of imitation metallic leaf held by said '10 10. A film support consisting of a strip wax coating to said support, and t coating l f paper coated with a, mixture composed of Of S128 UPOII the outer surface of Sald fillIl.

75 per cent of wax having a high melting point, and cumar. CARL P. OLSON.