Use of 3D printing for anticounterfeiting

Abstract

The invention pertains to the use of sophisticated chemical formulation and spectroscopic design methods to select taggants compatible with the 3D print medium that are easily detected spectroscopically but otherwise compatible with the product, structural integrity and stability, and aesthetics. A spectral pattern employs a different chemical or combination of chemicals to alter the formulation of all or some portion of the printed object so that its authenticity can be monitored later using a spectrometer.

1 . An article of manufacture created by means of additive manufacturing, the article comprising:
 a body of first material amassed by means of additive manufacturing, said body of first material providing a shaped structure upon which thin layers may be put into place;   a patch of second material put into place by means of additive manufacturing at a respective predetermined location on the body of first material, said patch of second material having a thickness and an area, said second material spectroscopically active when stimulated by a respective electromagnetic stimulation;   a patch of third material put into place by means of additive manufacturing, the patch of third material covering the patch of second material, said patch of third material having a thickness, said third material at least somewhat transparent to the spectroscopic activity of the second material.   
     
     
         2 . The article of manufacture of  claim 1  wherein the thickness of the second material is less than half a millimeter and the thickness of the third material is less than half a millimeter. 
     
     
         3 . The article of manufacture of  claim 1  wherein the area of the patch of second material is at least one square centimeter. 
     
     
         4 . The article of manufacture of  claim 1  wherein the patch of second material is substantially unnoticeable to the touch or to the eye. 
     
     
         5 . The article of manufacture of  claim 1  wherein the patch is composed at least partially of empty space rather than a second material. 
     
     
         6 . The article of manufacture of  claim 1  further characterized in that the spectroscopic activity of the second material comprises activity pursuant to ultraviolet/visible attenuated total reflectance spectroscopy, near-infrared diffuse reflectance spectroscopy, fluorescence excitation/emission measurement, x-ray fluorescence measurement, or Raman spectroscopy. 
     
     
         7 . The article of manufacture of  claim 1  wherein the additive manufacturing comprises 3D printing. 
     
     
         8 - 14 . (canceled) 
     
     
         15 . A method of manufacturing an article of manufacture, the method comprising the steps of:
 carrying out additive manufacturing using a first material, thereby yielding a first portion of the article of manufacture, the first material selected so as to have a first characteristic when viewed with the unaided human eye, and further selected so that, when stimulated with a particle or force to interrogate the first material, a response is generated in the form of particles or electromagnetic radiation and transformed into a distinctive electrical signal which can be read out to create a first spectral pattern; and   carrying out further additive manufacturing using a second material, thereby yielding a second portion of the article of manufacture, the second material selected so as to have the first characteristic when viewed with the unaided human eye, and further selected so that, when stimulated with a particle or force to interrogate the second material, a response is generated in the form of particles or electromagnetic radiation and transformed into a distinctive electrical signal which can be read out forming a second spectral pattern that can be mathematically distinguished from the first spectral pattern.   
     
     
         16 . The method of  claim 15  further comprising the steps of:
 stimulating the first portion of the article of manufacture with a particle or force, and detecting a response in the form of particles or electromagnetic radiation from the first portion of the article of manufacture by means of a detector; and 
 stimulating the second portion of the article of manufacture with a particle or force, and detecting a response in the form of particles or electromagnetic radiation from the second portion of the article of manufacture by means of the detector. 
 
     
     
         17 . The method of  claim 16  wherein the detector is composed of silicon and a composite of indium and gallium arsenide (InGaAS) materials. 
     
     
         18 - 52 . (canceled) 
     
     
         53 . Additive manufacturing apparatus for use by a user in manufacturing an article of manufacture from at least first and second feedstocks in response to a data file prepared by an entity other than the user, the data file containing an encrypted portion unreadable by the user, the apparatus comprising:
 a first store for the first feedstock;   a second store for the second feedstock;   a memory storing the data file;   programmable means drawing upon the first feedstock and drawing upon the second feedstock for carrying out additive manufacturing of the article of manufacture according to the data file;   the programmable means disposed to decrypt the encrypted portion of the data file and to draw differently upon the first feedstock and the second feedstock as a function of the encrypted portion of the data file.   
     
     
         54 . The apparatus of  claim 53  further comprising a non-destructive analytical means associated with the second store analyzing a characteristic of the second feedstock, the characteristic not visible to the user with the unaided eye, the programmable means disposed to draw upon the second feedstock only if the characteristic of the second feedstock meets some predetermined criterion. 
     
     
         55 . The apparatus of  claim 54  wherein the non-destructive analytical means comprises spectroscopic analysis. 
     
     
         56 - 95 . (canceled)