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Publication numberUS2773196 A
Publication typeGrant
Publication dateDec 4, 1956
Filing dateFeb 18, 1953
Priority dateFeb 18, 1953
Publication numberUS 2773196 A, US 2773196A, US-A-2773196, US2773196 A, US2773196A
InventorsHall Leonard I
Original AssigneeHall Leonard I
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Identification card
US 2773196 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

Dec. 4, 1956 HALL 2,773,196

IDENTIFICATION CARD Filed Feb. 18, 1953 INVENTOR. LEONARD I. HALL By W? ATURNEY United States Pat n IDENTIFICATION CARD Leonard I. Hall, Rochester, N. Y.

Application February 18, 1953, Serial No. 337,670

1 Claim. (Cl. 250106) The present invention relates to a method and to means for insuring against unauthorized persons, or persons without proper authority at the moment, carrying away documents, such as papers and maps, materials, packages, etc. from'an office or factory or from any classified area. As a corollary, the invention relates to a method and to means for insuring that only properly authorized persons may enter a classified area, and carry away from that area classified documents, materials, etc.

While it is comparatively easy to determine whether any metal object is being carried away from a restricted area Without authority by an employee or other person, it has not been possible heretofore to detect so readily the presence of secret documents and to prevent their unauthorized removal.

Recent revelations that persons, even in the higher echelons of government service, have carried away from their offices confidential documents, photostated them, and re turned them, have indicated the need for some simple, efficient method of preventing such unauthorized removal of documents. The continuing evidence that there are many persons in this country engaged in subversive and spying activities on behalf of foreign powers, serves but to accentuate that need. Moreover, cases have arisen, even where persons with properly-authorized access to classified documents, have carried away such documents without authority but with .no ulterior motive, and through carelessness have placed those documents in jeopardy of falling into the hands of unauthorized persons, even subversives.

A primary object of the present invention is to provide a method and means for marking documents, and materials of a highly secret or confidential nature so that they can readiiy be detected, and so that they can be locoted and identified definitely before they can be removed from a restricted area.

Another object of the invention is to provide a method and means whereby classified documents and other items can be marked in such manner that with simple detection devices and without destroying or harming the items their presence can be detected at an inspection point.

Another object of the invention is to provide means whereby the authority of a person to transport a classified item can be determined readily and without delay.

Still another object of the invention is to provide an identification card for persons authorized to transport classified material which will defy ordinary methods of counterfeiting.

Another object of the invention is to make it possible to mark pieces of. mailing matter so that they can readily be identified and sorted in the Post Ofiice or other department.

Other objects of the invention will be apparent hereinafter from the specification and from the recital of the appended claim.

Fig. 1 is a View of an identification card such as may be made according to one embodiment of this invention;

Fig. 2 is a view showing the top plastic layer :of this card stripped away sufficiently to show a lower layer of ice the card which bears radioactive material disposed in such way as to denote a certain number; and

Fig. 3 is a section through the card, on a somewhat enlarged scale, taken on the line 33 of Fig. 1.

In practicing the present invention a radioactive material is impressed on or impregnated into some portion of the fabric of the document or material, whose unauthorized removal it is desired to prevent. The impression or impregnation is preferably made at some particularly designated point or portion of the document or material, as over an important word of the document or at a particular part of a page thereof, :or in the case of a material in a designated portion of the fabric, or other material, so that if such radioactive marking means is deleted for any reason the removal of such identifying means will be immediately ascertainable.

The radioactive marking can readily be detected at an inspection point by use of any suitable means .for detecting a radioactive substance, such as a Geiger-Muller counter, or other known means for .detecting'the presence of a radioactive substance. All employees of a restricted department of a government bureau, or of a factory engaged in confidential work, can then tbfi required to pass a specified inspection point where they will be required to pass the Geiger-Muller or other detector. Persons wearing Wristwatches or other items with luminous dials containing radioactive material, which might affect the indicator, can be asked to remove such items before inspection so as to insure that the radioactivity of such an article will not interfere with the inspection.

The attachment of the radioactive material can be made by means of waxes, seals, adhesive tapes, or other suitable means impregnated with radioactive materials, or the radioactive materials can be embossed into the paper, letter, print, map, or other document or material which it is desired to protect etc. through use of a check protector, or similar device, acting upon the radioactive adhesive tape, or the like.

If no long term security is necessary, the indicia or tracer may be a material having soft beta-radiation characteristics. This is particularly useful inthe case of packages too large to secrete on the person.

For long term security of documents or other articles of extreme importance, the paper, fabric, or other material, may be water-marked with a radioactive symbol having a long life term, or have an adhesive seal or sealing wax applied thereto made of a long term radioactive material. Such radioactive materials as the isotopes of cobalt or manganese, which give off gamma rays and have no rays of harmful intensity, can be used. Such materials will be radioactive for a period of time up to ten years or more.

In practice, for example, when a letter or other document is finally approved and ready for signature, a security seal of radioactive transparent material can be placed over the most important words and/or embossed into the body of the document so that it can not thereafter be removed without destroying the document itself, or without permanently marring it. In .the case of letters, maps, or other papers a practice may be made of marking them with radio-active marking material all in the same place, for instance, at the center of a page, so that the marking cannot .be removed without it being immediately apparent.

Furthermore, in order to insure that only authorized persons be in possession of such radioactively protected documents, packages, or materials, these persons can be required to carry a card of identification, such as shown on the drawing, which is marked by radioactive material in a particular manner to identify that person. For instance, .the card 12 may be ruled off in a series of columns of squares, each square denoting a number, and the location of the square in the column designating a particular number, the columns being read from left to right, with the location of the square in a column denoting the numher which is to be read. For instance, if the card 12 were ruled off in six columns of five squares each, as shown, and the second square in the first column, the .third square in the second column, the first square in the third column, the fourth square in the fourth column, :the second square in the fifth column, and the fifth square in the sixth column were embossed or otherwise marked with radioactive material 14, then from the location of the squares in the columns, the card would designate the number 231425.

The number may be coded in such way that it can be read only when exposed to a Geiger-Muller counter or other proper identifying apparatus, and the number might not even be known to the person carrying the card and the security papers or packages. In this way the person carrying the classified documents or materials cannot ordinarily forge or counterfeit the number. The passcard can, if desired, be activated by a short life element so as to be good for only a few days. Unless both the passcard and the security papers give off the same number signals, when examined, it will be known that the transportation of the papers or documents, or other materials, is unauthorized.

In order that the radioactive code number be kept secret it might be placed between two layers 10 of opague passcard material if for any reason the code number would be subject to discoloration or would become obvious if on the outside face. In fact, the passcard might also be imprinted or written on the outside in the usual manner with one identifying number, as shown, and another number as part of a series with proper record kept at the issuing point for the cards, might be imprinted in radioactive materials on the card so that it can only be read when examined by the proper detecting apparatus. As a further precaution, it is also possible to make a radioactivated photoprint of the passcard by exposing the passcard to proper contact or near contact with properly sensitized material. The security card can also be examined by a fluoroscope for quick determination of its number.

An advantage of the invention is that it not only prevents transportation of classified documents and the like without authorization, but permits ready location of those documents if misplaced. It can be used, also, with advantage in the mails, Letters requiring special handling might be marked radio-actively by the sender for ready detection in the postoffice.

The radioactive material used in any of the various possible embodiments of the invention will be such as to have no harmful effects upon the human body. It has been definitely determined that gamma rays, when of limited intensity, are harmless to the human body.

While the invention has been described in connection with certain ditferent embodiments thereof, it will be understood that it is capable of further modification and uses; and this application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice in the art to which the invention pertains and as may be applied to the essential features hereinbefore set forth and as fall within the scope of the invention or the limits of the appended claim.

Having thus described my invention, what I claim is:

An identification card comprising a central layer and two outside layers, said central layer being disposed between the two outside layers and being ruled off in a plurality of columns of squares, certain of said squares being impregnated with radio-active material, that is invisible to the naked human eye, the location of an impregnated square in a column designating a specific numher, and the number of the card being determined by the location of all the impregnated squares, and the two outside layers being made of material opaque to visible light, one of said outside layers bearing a number visible to the naked human eye.

References Cited in the file of this patent UNITED STATES PATENTS 2,058,774 Colligan Oct. 27, 1936 2,378,328 Robinson May 22, 1942 2,407,381 Pecher Sept. 10, 1946 2,474,271 Meyer June 28, 1949 2,477,776 Talbot Aug. 2, 1949 OTHER REFERENCES Segre, abstract Ser. No. 526,338, published Nov. 29, 1949.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2058774 *Mar 31, 1934Oct 27, 1936Texas CoMarking petroleum products
US2378328 *May 22, 1942Jun 12, 1945Robinson ElmerMeans and method of identifying manufactured products
US2407381 *Jun 2, 1941Sep 10, 1946Research CorpMeans and method for transmitting secret intelligence
US2474271 *May 31, 1945Jun 28, 1949Meyer Harold FMethod for protection of objects
US2477776 *Jul 24, 1946Aug 2, 1949Sun Chemical CorpPrinting ink and method of using same
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2980801 *Feb 5, 1957Apr 18, 1961 Reumerman ctal
US2983354 *Sep 11, 1956May 9, 1961George EmberToken and system for using same
US3143649 *Mar 19, 1959Aug 4, 1964Nuclear Chicago CorpInformation coding and sensing by means of beta-ray backscattering
US3295651 *Mar 25, 1963Jan 3, 1967De La Rue Thomas & Co LtdMonetary tokens
US3564215 *May 15, 1969Feb 16, 1971Gen Nuclear IncIdentification device
US3652862 *Feb 4, 1970Mar 28, 1972Bayha Jack EMethod and apparatus for document validation
US4136778 *Oct 14, 1977Jan 30, 1979Burlington Industries, Inc.Linen sorter
US4363965 *Oct 3, 1980Dec 14, 1982The Franklin InstituteDetection and identification method employing mossbauer isotopes
US4795900 *Mar 26, 1987Jan 3, 1989Sadao KokubuOptical switch device employing a fluorescent substance with a radioactive element as a light source
US20060051494 *Sep 24, 2003Mar 9, 2006Sicpa Holding S.A.Method, device and system for the temporary marking of objects
WO2004065134A2 *Sep 24, 2003Aug 5, 2004Sicpa Holding S.A.Method, device and system for the temporary marking of objects
WO2004065134A3 *Sep 24, 2003Sep 23, 2004Xavier MarguerettazMethod, device and system for the temporary marking of objects
U.S. Classification250/303, 235/491, 235/488
International ClassificationB42D15/10
Cooperative ClassificationB42D2035/34, B42D2035/02, B42D15/10, B42D2033/08, B42D2035/06, B42D2033/32, B42D2035/08
European ClassificationB42D15/10