A steel object having hidden magnetically readable identification and the method for applying the identification

Claim 1

A vehicle, appliance or tool having a steel body part; a multiplicity of discontinuous alphanumeric indicia scattered over the body part, each of said indicia providing complete identification of the vehicle, appliance or tool, said indicia having line widths of at least 0.005 inch and comprising magnetizable particles dispersed in a nonmagnetizable binder, the particles having a coercivity at least twice that of said part and having a remanent magnetism exceeding 5 emu per gram; and a thin, opaque permanent protective layer of paint over the part and indicia providing a uniform surface hiding the identifying indicia; said magnetizable particles being present in sufficient amount to provide, when magnetized, a remanent magnetic moment exceeding 50 gauss at the surface of the paint to permit the identifying indicia to be readily inspected using a magnetic reader; the combination of paint and indicia providing a theft deterrent in that the vehicle, appliance or tool cannot be provided with counterfeit identification without removal of the paint and indicia, application of a multiplicity of false magnetizable indicia, and repainting.

Claim 3

A method of applying to at least one painted steel body part of a vehicle, appliance, or tool identification which is a theft deterrent in that the vehicle, appliance or tool cannot be provided with counterfeit identification without removal and replacement of a significant portion of the paint, the method comprising the steps of: preparing a dispersion of nonmagnetizable binder and magnetizable particles having a remanent magnetism above 5 emu per gram and coercivity at least twice that of said part; applying the dispersion to the part to provide a multiplicity of discontinuous alphanumeric identifying indicia scattered over the part, each of said indicia providing complete identification of the vehicle, appliance or tool, and having line widths of at least 0.005 inch; and applying over the identifying indicia a thin, opaque permanent protective layer of paint having sufficient thickness to provide a uniform exterior surface hiding the identifying indicia, the amount of magnetizable particles at all points of the indicia being selected to provide when magnetized, a remanent magnetic moment exceeding 50 gauss at the surface of the paint to permit convenient inspection of the identifying indicia using a magnetic reader.

Claim 4

A method of applying to at least one painted steel body part of a vehicle, appliance, or tool identification which is a theft deterrent in that the vehicle, appliance or tool cannot be provided with counterfeit identification without removal and replacement of a significant portion of the paint, the method comprising the steps of: preparing a dispersion of nonmagnetizable binder and magnetizable particles having a remanent magnetism above 5 emu per gram and coercivity at least twice that of said part; applying the dispersion to the part to provide a multiplicity of discontinuous alphanumeric identifying indicia scattered over the part, each of said indicia providing complete identification of the vehicle, appliance or tool, and having line widths of at least 0.005 inch; and applying over the identifying indicia a thin, opaque permanent protective layer of paint having sufficient thickness to provide a uniform exterior surface hiding the identifying indicia, the amount of magnetizable particles at all points of the indicia being selected to provide when magnetized, a remanent magnetic moment exceeding 50 gauss at the surface of the paint to permit convenient inspection of the identifying indicia using a magnetic reader.

Claim 6

A method of providing hidden magnetically readable identification on at least one painted steel body part of a vehicle, appliance or tool, which identification is a theft deterrent in that the vehicle, appliance or tool cannot be provided with counterfeit identification without removal and replacement of a significant portion of the paint, the method comprising the steps of: preparing a dispersion of nonmagnetizable binder and magnetizable particles having a remanent magnetism above 5 emu per gram and coercivity at least twice that of said part; applying the dispersion to the part to provide a multiplicity of discontinuous identifying indicia scattered over the part, each of said indicia providing complete identification of the vehicle, appliance, or tool, and having line widths of at least 0.005 inch; applying over the identifying indicia a thin, opaque permanent protective layer of paint having sufficient thickness to provide a uniform exterior surface hiding the identifying indicia, the amount of magnetizable particles at all points of the indicia being selected to provide, when magnetized, a remanent magnetic moment exceeding 50 gauss at the surface of the paint; magnetizing the particles in the indicia; and positioning adjacent the paint means for providing a visible image corresponding to the outline of the hidden indicia.

Claim 7

A method of providing hidden magnetically readable identification on at least one painted steel body part of a vehicle, appliance or tool, which identification is a theft deterrent in that the vehicle, appliance or tool cannot be provided with counterfeit identification without removal and replacement of a significant portion of the paint, the method comprising the steps of: preparing a dispersion of nonmagnetizable binder and magnetizable particles having a remanent magnetism above 5 emu per gram and coercivity at least twice that of said part; applying the dispersion to the part to provide a multiplicity of discontinuous identifying indicia scattered over the part, each of said indicia providing complete identification of the vehicle, appliance, or tool, and having line widths of at least 0.005 inch; applying over the identifying indicia a thin, opaque permanent protective layer of paint having sufficient thickness to provide a uniform exterior surface hiding the identifying indicia, the amount of magnetizable particles at all points of the indicia being selected to provide, when magnetized, a remanent magnetic moment exceeding 50 gauss at the surface of the paint; magnetizing the particles in the indicia; and positioning adjacent the paint means for providing a visible image corresponding to the outline of the hidden indicia.

Claim 8

A system for hidden magnetically readable identification on at least one painted steel body part of a vehicle, appliance or tool which identification is a theft deterrent in that the vehicle, appliance or tool cannot be provided with counterfeit identification without removal and replacement of a significant portion of the paint, the system comprising: a dispersion of nonmagnetizable binder and magnetizable particles having a remanent magnetism above 5 emu per gram and coercivity at least twice that of said part; means for applying the dispersion to the part to provide a multiplicity of discontinuous identifying indicia scattered over the part, each of said indicia providing complete identification of the vehicle, appliance, or tool, and having line widths of at least 0.005 inch; means for applying over the identifying indicia a thin, opaque permanent protective layer of paint having sufficient thickness to provide a uniform exterior surface hiding the identifying indicia, the amount of magnetizable particles at all points of the indicia being selected to provide, when magnetized, a remanent magnetic moment exceeding 50 gauss at the surface of the paint; means for magnetizing the particles in the indicia; and means positionable adjacent the opaque protective layer for providing a visible image corresponding to the outline of the hidden indicia.

Claim 9

A system for hidden magnetically readable identification on at least one painted steel body part of a vehicle, appliance or tool which identification is a theft deterrent in that the vehicle, appliance or tool cannot be provided with counterfeit identification without removal and replacement of a significant portion of the paint, the system comprising: a dispersion of nonmagnetizable binder and magnetizable particles having a remanent magnetism above 5 emu per gram and coercivity at least twice that of said part; means for applying the dispersion to the part to provide a multiplicity of discontinuous identifying indicia scattered over the part, each of said indicia providing complete identification of the vehicle, appliance, or tool, and having line widths of at least 0.005 inch; means for applying over the identifying indicia a thin, opaque permanent protective layer of paint having sufficient thickness to provide a uniform exterior surface hiding the identifying indicia, the amount of magnetizable particles at all points of the indicia being selected to provide, when magnetized, a remanent magnetic moment exceeding 50 gauss at the surface of the paint; means for magnetizing the particles in the indicia; and means positionable adjacent the opaque protective layer for providing a visible image corresponding to the outline of the hidden indicia.